1,663 results on '"University of Yaounde"'
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2. Plasmodium Vivax Among Duffy Negative Population in Cameroon. (VIBRANT)
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Barcelona Institute for Global Health, University of Yaounde 1, and Dr Innocent Ali, Senior Lecturer
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- 2023
Catalog
3. Efficacy and Safety of Artemether-Lumefantrine and Dihydroartemisinin-Piperaquine in Cameroon
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Biotechnology Center (BTC), University of Yaounde I, Cameroon, National Malaria Control Program (NMCP), Cameroon, Association Camerounaise pour le Marketing Social (ACMS), Cameroon, Impact Malaria, Cameroon, and Professor Wilfred Fon Mbacham, Principal Investigator, Professor of Public Health Biotechnology more...
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- 2022
4. Characteristics of Young-onset Diabetes in Sub-Saharan Africa (YODA) Study (YODA)
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University of Yaounde 1, University of Exeter, MRC/UVRI & LSHTM Uganda Research Unit, and Sobngwi Eugene, Professor
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- 2021
5. Artemisinin-Based Combination Therapy: Clinical Trials in Cameroon
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University of Yaounde, Cameroon Baptist Convention Health, and Brian Greenwood, Professor
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- 2021
6. Efficacy and Safety of Artesunate-amodiaquine and Artemether-lumefantrine for the Treatment of Malaria in Cameroon
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Biotechnology Center (BTC), University of Yaounde I, Cameroon, National Malaria Control Program (NMCP), Cameroon, Impact Malaria, Cameroon, Association Camerounaise pour le Marketing Social (ACMS), Cameroon, and Professor Wilfred Fon Mbacham, Professor Wilfred Fon Mbacham more...
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- 2021
7. Short-term Effects of Perindopril-amlodipine Versus Perindopril-indapamide in Type 2 Diabetes
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University of Yaounde 1 and Sobngwi Eugene, Medical Advisor
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- 2018
8. Effect of Morning Versus Evening Perindopril on Blood Pressure Control in People With Type 2 Diabetes (CHRONIC1)
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University of Yaounde 1 and Sobngwi Eugene, Professor of Endocrinology and Diabetes
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- 2018
9. Short Term Effect of Liraglutide Versus Vildagliptine on Insulin Secretion and Insulin Sensitivity in Type 2 Diabetes (LIRAVIS)
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University of Yaounde 1, University of Buea, and Sobngwi Eugene, Professor of Endocrinology and Diabetes
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- 2017
10. Anti-Malarial Drug Resistance in Cameroon
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University of Yaounde and Brian Greenwood, Professor
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- 2017
11. Research on the Economics of Artemisinin Combination Therapy (ACTs) for the Treatment of Malaria (REACT)
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University of Yaounde and University of Nigeria, Enugu Campus
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- 2016
12. Metabolic Effects of Treatment of Chronic Periodontitis in Non-diabetic Subjects (PARODIA2)
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University of Yaounde 1 and Sobngwi Eugene, Professor of Endocrinology and Diabetes
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- 2016
13. Improving Access to HbA1c in Sub Saharan Africa (IA3)
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Newcastle University, University of Yaounde 1, and Sobngwi Eugene, Senior Lecturer and Consultant Physician
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- 2016
14. Efficacy of Spironolactone in Cameroonian Diabetic Patients With Resistant Hypertension (SPIRY)
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University of Yaounde 1 and Sobngwi Eugene, Professor and Consultant Physician
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- 2015
15. Substance Use Disorders in HIV People of Cameroon
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Yaounde Central Hospital, Edea Regional Hospital, University of Yaounde 1, NYU Langone Health, and Jean Joel R. Bigna, Head Officer
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- 2015
16. Monitoring the Efficacy of Anthelmintics for the Treatment of Soil Transmitted Helminths P2 (ConWorm)
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Commonwealth Scientific and Industrial Research Organisation, Australia, World Health Organization, Institut Pasteur, Cambodia, The University of Queensland, Oswaldo Cruz Foundation, University of Nottingham, University of Yaounde 1, Ivo de Carneri, Pemba Island, Tanzania, National Institute of Malariology, Parasitology and Entomology, Vietnam, Jimma University, Fundación Huésped, Queensland Institute of Medical Research, and Institut Pasteur more...
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- 2014
17. Newer Versus Older Antihypertensive Agents in African Hypertensive Patients (NOAAH) Trial (NOAAH)
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University of Kinshasa, Yaounde Central Hospital, University of Yaounde, University of Libreville, Institute of Cardiology Abidjan, University of Ilorin Teaching Hospital, University of Nigeria, Enugu Campus, Hospital Aristide Le Dantec, Dakar, Senegal, and Jan A. Staessen, Professor of Medicine, MD, PhD more...
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- 2013
18. The Effects of Spirulina Platensis on Insulin Resistance in HIV-infected Patients
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University of Yaounde, Antenna Technologies, and Dr Sobngwi Eugene
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- 2011
19. Effect of Irvingia Gabonensis (Bush Mango)on Parameters Associated With Metabolic Syndrome
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University of Yaounde and Pr. Julius Oben, CSO
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- 2008
20. ProAlgaZyme Novel Algae Infusion: Applications in Immunodeficiency
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University of Yaounde
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- 2007
21. ProAlgaZyme Novel Algae Infusion: Applications in Metabolic Syndrome
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University of Yaounde
- Published
- 2007
22. Prevention of β-amyloid-induced toxicity in a differentiated neuronal (IMR32) cell line by Khaya grandifololia (Welw) C. DC.
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Research Training Fellowship for Developing Countries Scientists (RTF-DCS), India, Armand, Ella Fils; 1 Laboratory of Pharmacology and Toxicology, Department of Biochemistry, Faculty of Science, University of Yaounde 1, Yaounde, Cameroon. 2 Department of Studies & Research in Biochemistry, Mangalore University, Post Graduate Centre, Chikka Aluvara-571232, Kodagu, Karnataka, India. 3 Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore-575018, Karnataka, India., Shantaram, Manjula; Department of Studies & Research in Biochemistry, Mangalore University, Post Graduate Centre, Chikka Aluvara-571232, Kodagu, Karnataka, India., Fewou, Simon Ngamli; Faculty of Health Science, Université des Montagnes, Bangangté, Cameroon., Njayou, Frédéric Nico; Laboratory of Pharmacology and Toxicology, Department of Biochemistry, Faculty of Science, University of Yaounde 1, Yaounde, Cameroon., Deolankar, Sayali Chandrashekhar; Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore-575018, Karnataka, India., Modi, Prashant Kumar; Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore-575018, Karnataka, India., Moundipa, Paul Fewou; Laboratory of Pharmacology and Toxicology, Department of Biochemistry, Faculty of Science, University of Yaounde 1, Yaounde, Cameroon., Research Training Fellowship for Developing Countries Scientists (RTF-DCS), India, Armand, Ella Fils; 1 Laboratory of Pharmacology and Toxicology, Department of Biochemistry, Faculty of Science, University of Yaounde 1, Yaounde, Cameroon. 2 Department of Studies & Research in Biochemistry, Mangalore University, Post Graduate Centre, Chikka Aluvara-571232, Kodagu, Karnataka, India. 3 Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore-575018, Karnataka, India., Shantaram, Manjula; Department of Studies & Research in Biochemistry, Mangalore University, Post Graduate Centre, Chikka Aluvara-571232, Kodagu, Karnataka, India., Fewou, Simon Ngamli; Faculty of Health Science, Université des Montagnes, Bangangté, Cameroon., Njayou, Frédéric Nico; Laboratory of Pharmacology and Toxicology, Department of Biochemistry, Faculty of Science, University of Yaounde 1, Yaounde, Cameroon., Deolankar, Sayali Chandrashekhar; Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore-575018, Karnataka, India., Modi, Prashant Kumar; Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore-575018, Karnataka, India., and Moundipa, Paul Fewou; Laboratory of Pharmacology and Toxicology, Department of Biochemistry, Faculty of Science, University of Yaounde 1, Yaounde, Cameroon. more...
- Abstract
Alzheimer’s disease (AD) belongs to the class of neurodegenerative disorder and is biochemically characterized by amyloid-β (Aβ) plaques deposition, accumulation of neurofibrillary tangles (NFTs) accumulation and ultimately neuronal loss. Even though, the progress made in developing efficient AD therapy, there is no effective drug capable to stop and/or slow down AD progression. In the current article, we investigated the neuroprotective effect of Khaya grandifololia crude extract and fraction 2 against Aβ42-induced cytotoxicity and hyperphosphorylation of tau protein in differentiated neuronal cells (IMR32).Reactive oxygen species production, apoptosis and mitochondrial dynamics and function, synaptic protein, and tau phosphorylation were evaluated using fluorescence microscopy and immunoblotting. Cell viability was assessed using the MTT assay.Findings revealed that exposure of differentiated IMR32 cells to Aβ42 alone induced the impairment of mitochondrial dynamics, decrease synaptic protein expression and increase hyperphosphorylation of tau protein (phospho tau181). In contrast, the presence of crude extract and KGf2 significantly inhibited the cleavage of Caspase-3 activation. In addition, the levels of synaptic proteins (Symptosomal associated protein 25 and Synaptosin) and superoxide dismutase were restored upon treatment with crude extract and fraction 2. Hyperphosphorylation of tau protein (Thr181) and ERK (Thr202/Tyr205) activities were also significantly reduced after treatment with crude extract and fraction 2.Our findings suggest that KG extract is a potential source for candidate drug against AD and may contribute to the development of efficient therapeutic strategy against AD. more...
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- 2021
23. Integrated Approach to Eco-Friendly Thermoplastic Composites Based on Chemically Recycled PET Co-Polymers Reinforced with Treated Banana Fibres
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UCL - SST/IMCN/BSMA - Bio and soft matter, University of Yaounde - Macromolecular Chemistry Unit, UCL - SST/IMMC/IMAP - Materials and process engineering, Kuete, Martial, Van Velthem, Pascal, Ballout, Wael, Nysten, Bernard, Devaux, Jacques, Ndikontar, Maurice Kor, Pardoen, Thomas, Bailly, Christian, UCL - SST/IMCN/BSMA - Bio and soft matter, University of Yaounde - Macromolecular Chemistry Unit, UCL - SST/IMMC/IMAP - Materials and process engineering, Kuete, Martial, Van Velthem, Pascal, Ballout, Wael, Nysten, Bernard, Devaux, Jacques, Ndikontar, Maurice Kor, Pardoen, Thomas, and Bailly, Christian more...
- Abstract
A major societal issue of disposal and environmental pollution is raised by the enormous and fast-growing production of single-use polyethylene terephthalate (PET) bottles, especially in developing countries. To contribute to the problem solution, an original route to recycle PET in the form of value-added environmentally friendly thermoplastic composites with banana fibres (Musa acuminata) has been developed at the laboratory scale. Banana fibres are a so far undervalued by-product of banana crops with great potential as polymer reinforcement. The melt-processing constraints of commercial PET, including used bottles, being incompatible with the thermal stability limits use of natural fibres; PET has been modified with bio-sourced reactants to produce co-polymers with moderate processing temperatures below 200°C. First, commercial PET were partially glycolyzed with 1.3-propanediol to produce co-oligomers of about 20 repeating units, which were next chain extended with succinic anhydride and post-treated in a very unusual “soft solid state” process at temperatures in the vicinity of the melting point to generate co-polymers with excellent ductility. The molar mass build-up reaction is dominated by esterification of the chain ends and benefits from the addition of succinic anhydride to rebalance the acid-to-hydroxyl end-group ratio. Infra-red spectroscopy and intrinsic viscosity were extensively used to quantify the concentration of chain ends and the average molar mass of the co-polymers at all stages of the process. The best co-polymers are crystallisable, though at slow kinetics, with a Tg of 48°C and a melting point strongly dependent upon thermal history. The composites show high stiffness (4.8 GPa at 20% fibres), consistent with the excellent dispersion of the fibres and a very high interfacial cohesion. The strong adhesion can be tentatively explained by covalent bonding involving unreacted succinic anhydride in excess during solid stating. A first approach to more...
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- 2022
24. Water Quality And Benthic Macroinvertebrates Of Tropical Forest Stream In South-West Region, Cameroon
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University of Yaounde 1, Départment of Animales Biology and Physiology, MENBOHAN, Samuel FOTO, NWAHA, Mathias, BIRAM à NGON, Eric Belmond, DZVI, Jean, BOUDEM, Rita Cecile, SOB NANGOU, Paul Bertrand, NYAME MBIA, Donald-l’or, University of Yaounde 1, Départment of Animales Biology and Physiology, MENBOHAN, Samuel FOTO, NWAHA, Mathias, BIRAM à NGON, Eric Belmond, DZVI, Jean, BOUDEM, Rita Cecile, SOB NANGOU, Paul Bertrand, and NYAME MBIA, Donald-l’or more...
- Abstract
A study was carried out in Ndongo stream, located in Buea, from May to October 2017, to assess the water quality and evaluate the structure of benthic macroinvertebrates. Physicochemical analysis showed that water from Ndongo was well oxygenated (82.21 ± 6.59 %), slightly acidic (pH=6.82 ± 0.22 UC) and alkaline with low quantities of nitrogen compound (2.9 ± 3.57 mg/L NO3+; 0.02 ± 0.02 mg/L NO2– and 0.89 ± 1.78 mg/L NH4+). Regarding the biology of macroinvertebrates, a total of 2058 individuals were collected and identified into 4 phyla, 5 classes, 11 orders, 32 families and belonging to 44 genera. The Shannon & Weaver and Pielou evenness reveal that the benthic macroinvertebrates were more diversified in upstream. more...
- Published
- 2021
25. Hypotensive and antihypertensive effects of Pterocarpus santalinoides stem barks aqueous extract on oxidized palm oil and sucrose-induced hypertensive rats
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Yamjom Ramatou, Chinte; University of Yaoundé 1, Tsofack Florence, Ngueguim; University of Yaounde 1, Kamkumo Raceline, Gounoue; Université of Yaoundé 1, Donfack mirielle, Metchi; Université of Yaoundé 1, Danielle Claude, Bilanda; Université of Yaoundé 1, Théophile, Dimo; Université of Yaoundé 1, Yamjom Ramatou, Chinte; University of Yaoundé 1, Tsofack Florence, Ngueguim; University of Yaounde 1, Kamkumo Raceline, Gounoue; Université of Yaoundé 1, Donfack mirielle, Metchi; Université of Yaoundé 1, Danielle Claude, Bilanda; Université of Yaoundé 1, and Théophile, Dimo; Université of Yaoundé 1 more...
- Abstract
Objective: This study was aimed to evaluate the hypotensive and antihypertensive effects of the stem barks aqueous extract of Pterocarpus santalinoides (AEPS) on oxidized palm oil and sucrose-induced hypertensive rats.Methods: Hypotensive effects of AEPS, were evaluated in Wistar rats by intravenous injection of the extract (5, 10, 20 and 30 mg/kg). The arterial pressure and heart rate were directly recorded. The action mechanism through which the extract exhibits hypotensive effect was performed. Antihypertensive effects of AEPS were evaluated by administrating the enriched diet in oxidized palm oil and sucrose (DOS) concomitantly with AEPS (50, 100 and 200 mg/kg) during 8 weeks.Results: AEPS provoked a significant immediate decrease of mean blood pressure and heart rate. Atropine and reserpine, reduced significantly (p < 0.01) the hypotensive effect of P. santalinoides. The enriched diet in oxidized palm oil and sucrose significantly increased the blood pressure and heart rate (p < 0.001) by the increase (p < 0.001) of total cholesterol, triglycerides, LDL-cholesterol and a decrease of HDL-cholesterol. DOS also increased the liver (AST and ALT) and kidney (urea, creatinine) marker levels. The activity of SOD, catalase and MDA levels were significantly increased. The AEPS prevented the increase (p < 0.001) in blood pressure and heart rate. The Lipid profile, liver and kidney functions and oxidative stress markers were also improved.Conclusion: Pterocarpus santalinoides exhibits a hypotensive activity through muscarinic cholinergic receptors and sympatic central nervous system. It also prevents DOS-induced hypertension by attenuating hyperlipidemia, oxidative stress, liver and kidney damages initiated by DOS. more...
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- 2020
26. Hibiscus noldea (Malvaceae) Aqueous Extract Prevents Insulin Resistance and Protects Pancreatic Islets From Dexamethasone Damages in Rat.
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Florence, Ngueguim Tsofack; University of Yaounde 1, Jean Philippe, Djientcheu Tientcheu; University of Yaounde 1, Hubert, Donfack Jean; University of Dschang, Raceline, Gounoue Kamkumo; University of Yaounde1, Paul Desire, Dzeufiet Djomeni; University of Yaounde 1, Pierre, Kamtchouing; University of Yaounde 1, Theophile, Dimo; University of Yaounde 1, Florence, Ngueguim Tsofack; University of Yaounde 1, Jean Philippe, Djientcheu Tientcheu; University of Yaounde 1, Hubert, Donfack Jean; University of Dschang, Raceline, Gounoue Kamkumo; University of Yaounde1, Paul Desire, Dzeufiet Djomeni; University of Yaounde 1, Pierre, Kamtchouing; University of Yaounde 1, and Theophile, Dimo; University of Yaounde 1 more...
- Abstract
Hibiscus noldea leaves-stems aqueous extract is used in Cameroonian traditional medecine to manage diabetes. To investigate the preventive effect of Hibiscus noldea aqueous extract on dexamethasone-induced insulin resistance, the animals received one of the following treatments: distilled water (10 mL/kg), metformine (200 mg/kg), or H. noldea (100 or 200 mg/kg) concomitantly with dexamethasone (0.5 mg/kg, ip) for ten days. Body weight was evaluated daily and blood glucose levels were measured. At the end of experiment, insulin sensitivity test was performed and lipid profile, transaminases Aspartate amino transferase, Alanin amino transferase, malondialdehyde, superoxide dismutase, catalase, and reduced glutathione were evaluated. Histological analysis of the liver was investigated to estimate glycogen content using Periodic Acid Schiff coloration and histomorphometry of pancreatic islets area was performed.The administration of dexamethasone during ten days induced body weight loss, hyperglycaemia, insulinresistance, an imbalance in lipid profile, an increase in transaminases and oxidative stress. Dexamethasone treatment also induced an increase in the pancreatic islets area and depletion in the levels of hepatic glycogen. Concomitant administration of dexamethasone and the aqueous plant extract prevented the rise in blood glucose levels, reduced insulinresistance, improved lipid profile and oxidative status. The aqueous extract of H. noldea prevented the use of glycogen storage and the increase in pancreatic islet area in dose dependent manner.Conclusion: The stem leaves aqueous extract from Hibiscus noldea have the ability to reduce insulinresistance via its antihyperglycaemic, hypolipidemic and antioxidant activities. These results justify the use of this extract in the management of diabetic state. more...
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- 2017
27. Determinants of internal resources of small and medium sized-enterprises in Cameroon
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Mandiefe, Serge Piabuo; University of Yaounde II, Soa, Bafon, Jonas Chia; University of Yaounde II, Soa, Mandiefe, Serge Piabuo; University of Yaounde II, Soa, and Bafon, Jonas Chia; University of Yaounde II, Soa more...
- Abstract
Financing decisions have direct impact on financial structure and financial performance of firms. The aim of this study is to examine the specificity of capital structure of SMEs and that internal financial resources of Cameroonian SMEs. A binary discrete choice regression; the probit model is used to estimate the probability of the use of internal resource as principal financing source, World Bank 2009 enterprise survey was used in this study. Descriptive statistics was also used to verify the fact that the financial structure of SMEs differ from that of large firms. The principal results of this research shows that SMEs use more of internal sources of finance while large firms use more of external financing. We also noticed that when SMEs are family owned, sole proprietors have a higher probability of using internal source of financing as the principal source of financing, we also noticed that informal enterprises use more of non-bank external financing. more...
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- 2015
28. Body Mass Index, Blood Pressure and Hypertension Subtypes among Untreated Hypertensive Cameroonians
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Azantsa, Boris G. K., P.O. Box. 63, Buea, Cameroon, Department of Biochemistry, Faculty of Science, University of Yaounde I, Cameroon., Ntentié, Raïssa F., Mbong, Mary-ann A., Kengne, Anne-pascale N., Kuaté, Dieudonné, Dakam, William, Yangoua, Huguette C. M., Ngondi, Laure J., and Oben, Julius more...
- Subjects
hypertension subtypes ,prehypertension ,Hypertension ,BMI ,epidemiology ,Cameroon - Abstract
Aims: To study the prevalence of hypertension hemodynamic subtypes, prehypertension, hypertension (HTN) stages 1 and 2 as well as to evaluate the influence of overweight and obesity on those prevalences among untreated hypertensive Cameroonians. Study Design: This study was descriptive and cross-sectional. Place and Duration of the Study: Participants were randomly selected in Yaounde, Nkongsamba and Foumban from January 2009 to October 2012. Methodology: It involved 7042 Cameroonians of both sexes aged 18-85 years old. Blood pressure categories were defined using the 7th report of Joint National committee on hypertension. Hypertension subtypes were defined as Isolated Systolic Hypertension (ISH) [Systolic Blood Pressure (SBP)≥140 mmHg and Diastolic Blood Pressure (DBP) < 90 mm Hg]; Isolated Diastolic Hypertension (IDH) (SBP more...
- Published
- 2013
- Full Text
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29. In vitro cytotoxicity studies of sixteen plants used for pregnant women’s health conditions in Menoua Division-West Cameroon
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University of Dschang, Yemele, Didiane Mefokou; University of Dschang, Telefo, Bruno Phelix; University of Dschang, Goka, Stephanie Chekem; University of Dschang, Nguelefack, Benoit Telesphore; University of Dschang, Fodouop, Pierre Simeon chegaing; University of Dschang and University of Ngaoundere, Tagne, Richard Simo; University of Dschang and University of Ngaoundere, Lienou, Landry Lienou; University of Dschang, Nguemo, Filomain; University of Köln, Moundipa, Paul Fewou; University of Yaounde I, University of Dschang, Yemele, Didiane Mefokou; University of Dschang, Telefo, Bruno Phelix; University of Dschang, Goka, Stephanie Chekem; University of Dschang, Nguelefack, Benoit Telesphore; University of Dschang, Fodouop, Pierre Simeon chegaing; University of Dschang and University of Ngaoundere, Tagne, Richard Simo; University of Dschang and University of Ngaoundere, Lienou, Landry Lienou; University of Dschang, Nguemo, Filomain; University of Köln, and Moundipa, Paul Fewou; University of Yaounde I more...
- Abstract
In Cameroon, many plants are used in traditional medicine for the treatment of pregnancy and childbirth complaints. However, toxicological potential of most of these plants have not been investigated. In order to evaluate the degree of safety of their users, in vitro cytotoxic potentials of sixteen of these medicinal plants were subjected to the assay using the brine shrimp lethality assay. From this study, the aqueous extract of plant Rauvolfia vomitoria bark was found to be cytotoxic and that of Ageratum conyzoides stem and leaves slightly cytotoxic, with LC50 values of 17.62 and 99.17µg/ml, respectively. The least toxic plant extracts were Aloe buttneri, Commelina benghalensis, Ipomoea tenuirostrisandNelsonia canescens, (LC50 value > 105 µg/ml). Overall fourteen extracts were found to be non-toxic. Most herbal remedies were non cytotoxic but it would be necessary to complete these cyto-toxicological information by mutagenicity, teratogenicity tests as welle as in vivo toxicological tests on animals. more...
- Published
- 2015
30. Distribution patterns of Vibrionaceae abundance on the landing stages in coastal area: Understanding the influence of physicochemical variables by using multiple linear regression models and corrgram for matrix correlation
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Olive Vivien Noah Ewoti, Antoine Tamsa Arfao, Blandine Pulch erie Tamatcho Kweyang, Joel Brice Tchuimaleu Emadjeu, Nola Moise, Sim eon Tchakont e, Luciane Marlyse Moungang, Belengfe Sylvie Chinche, T elesphore Sime-Ngando, Mamert Fils Onana, Hydrobiology and Environment Laboratory, University of Yaounde 1, Faculty of Sciences, P.O. Box 812 Yaounde, Cameroon, Department of Aquatic Ecosystems Management, Institute of Fisheries and Aquatic Sciences, University of Douala, Microbiology Laboratory, University of Yaounde 1, Faculty of Sciences, Laboratoire Microorganismes : Génome et Environnement (LMGE), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Université de Yaoundé I, Université de Douala, and University of Yaoundé [Cameroun] more...
- Subjects
0106 biological sciences ,0301 basic medicine ,Veterinary medicine ,Aerobic bacteria ,Vibrionaceae ,030106 microbiology ,environmental parameters ,Plant Science ,01 natural sciences ,Microbiology ,distribution patterns ,03 medical and health sciences ,Abundance (ecology) ,010608 biotechnology ,Linear regression ,14. Life underwater ,Multiple linear regression ,Vibrio alginolyticus ,biology ,Vibrio parahaemolyticus ,biology.organism_classification ,6. Clean water ,Vibrio ,Infectious Diseases ,visualization of corrgram ,Vibrio fluvialis ,[SDE]Environmental Sciences - Abstract
The present work used multiple linear regression (MLR) models and corrgram to assess the importance of environmental parameters on diversity and abundance dynamics of Vibrio sp. in waters of few landing stages in the city of Douala (Cameroon). It was recorded in all the five selected stations, the presence of four species of Vibrio namely, Vibrio parahaemolyticus, Vibrio cholerae, Vibrio fluvialis and Vibrio alginolyticus whose highest abundance reached 5.65, 6.26, 4.9 and 4.83 log CFU/100 ml respectively. Vibrio cholerae was the most isolated during the study with a frequency of 65%. The abundance dynamics of these germs is strongly influenced by nitrates, salinity, dissolved carbon dioxyde (CO2) and ammonium ions (NH4+). The visualization of corrgram shows high degree of association between studied parameters. We note a coefficient of determination r2 = 0.50 for the multiple linear regression model for Heterotrophic Aerobic Bacteria (HAB) and a coefficient of determination r2 = 0.58 for the MLR model for V. cholerae. The physicochemical parameters explain at 43% (r2 = 0.43) the distribution of the abundances of V. parahaemolyticus, at 45% (r2 = 0.45) the distribution of abundances of V. alginolyticus and at 26% (r2 = 0.26) for V. fluvialis. Keywords: Multiple linear regression, visualization of corrgram, environmental parameters, distribution patterns, Vibrionaceae. more...
- Published
- 2021
- Full Text
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31. Taking the pulse of Earth's tropical forests using networks of highly distributed plots
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Forest, Plots net, Blundo, Cecilia, Carilla, Julieta, Grau, Ricardo, Malizia, Agustina, Malizia, Lucio, Osinaga-Acosta, Oriana, Bird, Michael, Bradford, Matt, Catchpole, Damien, Ford, Andrew, Graham, Andrew, Hilbert, David, Kemp, Jeanette, Laurance, Susan, Laurance, William, Ishida, Francoise Yoko, Marshall, Andrew, Waite, Catherine, Woell, Hannsjoerg, Bastin, Jean Francois, Bauters, Marijn, Beeckman, Hans, Boeckx, Pfascal, Bogaert, Jan, De Canniere, Charles, de Haulleville, Thales, Doucet, Jean Louis, Hardy, Olivier, Hubau, Wannes, Kearsley, Elizabeth, Verbeeck, Hans, Vleminckx, Jason, Brewer, Steven W., Alarcón, Alfredo, Araujo-Murakami, Alejandro, Arets, Eric, Arroyo, Luzmila, Chavez, Ezequiel, Fredericksen, Todd, Villaroel, René Guillén, Sibauty, Gloria Gutierrez, Killeen, Timothy, Licona, Juan Carlos, Lleigue, John, Mendoza, Casimiro, Murakami, Samaria, Gutierrez, Alexander Parada, Pardo, Guido, Peña-Claros, Marielos, Poorter, Lourens, Toledo, Marisol, Cayo, Jeanneth Villalobos, Viscarra, Laura Jessica, Vos, Vincent, Ahumada, Jorge, Almeida, Everton, Almeida, Jarcilene, de Oliveira, Edmar Almeida, da Cruz, Wesley Alves, de Oliveira, Atila Alves, Carvalho, Fabrício Alvim, Obermuller, Flávio Amorim, Andrade, Ana, Carvalho, Fernanda Antunes, Vieira, Simone Aparecida, Aquino, Ana Carla, Aragão, Luiz, Araújo, Ana Claudia, Assis, Marco Antonio, Gomes, Jose Ataliba Mantelli Aboin, Baccaro, Fabrício, de Camargo, Plínio Barbosa, Barni, Paulo, Barroso, Jorcely, Bernacci, Luis Carlos, Bordin, Kauane, de Medeiros, Marcelo Brilhante, Broggio, Igor, Camargo, José Luís, Cardoso, Domingos, Carniello, Maria Antonia, Rochelle, Andre Luis Casarin, Castilho, Carolina, Castro, Antonio Alberto Jorge Farias, Castro, Wendeson, Ribeiro, Sabina Cerruto, Costa, Flávia, de Oliveira, Rodrigo Costa, Coutinho, Italo, Cunha, John, da Costa, Lola, da Costa Ferreira, Lucia, da Costa Silva, Richarlly, da Graça Zacarias Simbine, Marta, de Andrade Kamimura, Vitor, de Lima, Haroldo Cavalcante, de Oliveira Melo, Lia, de Queiroz, Luciano, de Sousa Lima, José Romualdo, do Espírito Santo, Mário, Domingues, Tomas, dos Santos Prestes, Nayane Cristina, Carneiro, Steffan Eduardo Silva, Elias, Fernando, Eliseu, Gabriel, Emilio, Thaise, Farrapo, Camila Laís, Fernandes, Letícia, Ferreira, Gustavo, Ferreira, Joice, Ferreira, Leandro, Ferreira, Socorro, Simon, Marcelo Fragomeni, Freitas, Maria Aparecida, García, Queila S., Manzatto, Angelo Gilberto, Graça, Paulo, Guilherme, Frederico, Hase, Eduardo, Higuchi, Niro, Iguatemy, Mariana, Barbosa, Reinaldo Imbrozio, Jaramillo, Margarita, Joly, Carlos, Klipel, Joice, do Amaral, Iêda Leão, Levis, Carolina, Lima, Antonio S., Dan, Maurício Lima, Lopes, Aline, Madeiros, Herison, Magnusson, William E., dos Santos, Rubens Manoel, Marimon, Beatriz, Junior, Ben Hur Marimon, Grillo, Roberta Marotti Martelletti, Martinelli, Luiz, Reis, Simone Matias, Medeiros, Salomão, Meira-Junior, Milton, Metzker, Thiago, Morandi, Paulo, do Nascimento, Natanael Moreira, Moura, Magna, Müller, Sandra Cristina, Nagy, Laszlo, Nascimento, Henrique, Nascimento, Marcelo, Lima, Adriano Nogueira, de Araújo, Raimunda Oliveira, Silva, Jhonathan Oliveira, Pansonato, Marcelo, Sabino, Gabriel Pavan, de Abreu, Karla Maria Pedra, Rodrigues, Pablo José Francisco Pena, Piedade, Maria, Rodrigues, Domingos, Rodrigues Pinto, José Roberto, Quesada, Carlos, Ramos, Eliana, Ramos, Rafael, Rodrigues, Priscyla, de Sousa, Thaiane Rodrigues, Salomão, Rafael, Santana, Flávia, Scaranello, Marcos, Bergamin, Rodrigo Scarton, Schietti, Juliana, Schöngart, Jochen, Schwartz, Gustavo, Silva, Natalino, Silveira, Marcos, Seixas, Cristiana Simão, Simbine, Marta, Souza, Ana Claudia, Souza, Priscila, Souza, Rodolfo, Sposito, Tereza, Junior, Edson Stefani, do Vale, Julio Daniel, Vieira, Ima Célia Guimarães, Villela, Dora, Vital, Marcos, Xaud, Haron, Zanini, Katia, Zartman, Charles Eugene, Ideris, Nur Khalish Hafizhah, Metali, Faizah binti Hj, Salim, Kamariah Abu, Saparudin, Muhd Shahruney, Serudin, Rafizah Mat, Sukri, Rahayu Sukmaria, Begne, Serge, Chuyong, George, Djuikouo, Marie Noel, Gonmadje, Christelle, Simo-Droissart, Murielle, Sonké, Bonaventure, Taedoumg, Hermann, Zemagho, Lise, Thomas, Sean, Baya, Fidèle, Saiz, Gustavo, Espejo, Javier Silva, Chen, Dexiang, Hamilton, Alan, Li, Yide, Luo, Tushou, Niu, Shukui, Xu, Han, Zhou, Zhang, Álvarez-Dávila, Esteban, Escobar, Juan Carlos Andrés, Arellano-Peña, Henry, Duarte, Jaime Cabezas, Calderón, Jhon, Bravo, Lina Maria Corrales, Cuadrado, Borish, Cuadros, Hermes, Duque, Alvaro, Duque, Luisa Fernanda, Espinosa, Sandra Milena, Franke-Ante, Rebeca, García, Hernando, Gómez, Alejandro, González-M., Roy, Idárraga-Piedrahíta, Álvaro, Jimenez, Eliana, Jurado, Rubén, Oviedo, Wilmar López, López-Camacho, René, Cruz, Omar Aurelio Melo, Polo, Irina Mendoza, Paky, Edwin, Pérez, Karen, Pijachi, Angel, Pizano, Camila, Prieto, Adriana, Ramos, Laura, Correa, Zorayda Restrepo, Richardson, James, Rodríguez, Elkin, Rodriguez M., Gina M., Rudas, Agustín, Stevenson, Pablo, Chudomelová, Markéta, Dancak, Martin, Hédl, Radim, Lhota, Stanislav, Svatek, Martin, Mukinzi, Jacques, Ewango, Corneille, Hart, Terese, Yakusu, Emmanuel Kasongo, Lisingo, Janvier, Makana, Jean Remy, Mbayu, Faustin, Toirambe, Benjamin, Mukendi, John Tshibamba, Kvist, Lars, Nebel, Gustav, Báez, Selene, Céron, Carlos, Griffith, Daniel M., Andino, Juan Ernesto Guevara, Neill, David, Palacios, Walter, Peñuela-Mora, Maria Cristina, Rivas-Torres, Gonzalo, Villa, Gorky, Demissie, Sheleme, Gole, Tadesse, Gonfa, Techane, Ruokolainen, Kalle, Baisie, Michel, Bénédet, Fabrice, Betian, Wemo, Bezard, Vincent, Bonal, Damien, Chave, Jerôme, Droissart, Vincent, Gourlet-Fleury, Sylvie, Hladik, Annette, Labrière, Nicolas, Naisso, Pétrus, Réjou-Méchain, Maxime, Sist, Plinio, Blanc, Lilian, Burban, Benoit, Derroire, Géraldine, Dourdain, Aurélie, Stahl, Clement, Bengone, Natacha Nssi, Chezeaux, Eric, Ondo, Fidèle Evouna, Medjibe, Vincent, Mihindou, Vianet, White, Lee, Culmsee, Heike, Rangel, Cristabel Durán, Horna, Viviana, Wittmann, Florian, Adu-Bredu, Stephen, Affum-Baffoe, Kofi, Foli, Ernest, Balinga, Michael, Roopsind, Anand, Singh, James, Thomas, Raquel, Zagt, Roderick, Murthy, Indu K., Kartawinata, Kuswata, Mirmanto, Edi, Priyadi, Hari, Samsoedin, Ismayadi, Sunderland, Terry, Yassir, Ishak, Rovero, Francesco, Vinceti, Barbara, Hérault, Bruno, Aiba, Shin Ichiro, Kitayama, Kanehiro, Daniels, Armandu, Tuagben, Darlington, Woods, John T., Fitriadi, Muhammad, Karolus, Alexander, Khoon, Kho Lip, Majalap, Noreen, Maycock, Colin, Nilus, Reuben, Tan, Sylvester, Sitoe, Almeida, Coronado G., Indiana, Ojo, Lucas, de Assis, Rafael, Poulsen, Axel Dalberg, Sheil, Douglas, Pezo, Karen Arévalo, Verde, Hans Buttgenbach, Moscoso, Victor Chama, Oroche, Jimmy Cesar Cordova, Valverde, Fernando Cornejo, Medina, Massiel Corrales, Cardozo, Nallaret Davila, de Rutte Corzo, Jano, del Aguila Pasquel, Jhon, Llampazo, Gerardo Flores, Freitas, Luis, Cabrera, Darcy Galiano, Villacorta, Roosevelt García, Cabrera, Karina Garcia, Soria, Diego García, Saboya, Leticia Gatica, Rios, Julio Miguel Grandez, Pizango, Gabriel Hidalgo, Coronado, Eurídice Honorio, Huamantupa-Chuquimaco, Isau, Huasco, Walter Huaraca, Aedo, Yuri Tomas Huillca, Peña, Jose Luis Marcelo, Mendoza, Abel Monteagudo, Rodriguez, Vanesa Moreano, Vargas, Percy Núñez, Ramos, Sonia Cesarina Palacios, Camacho, Nadir Pallqui, Cruz, Antonio Peña, Arevalo, Freddy Ramirez, Huaymacari, José Reyna, Rodriguez, Carlos Reynel, Paredes, Marcos Antonio Ríos, Bayona, Lily Rodriguez, del Pilar Rojas Gonzales, Rocio, Peña, Maria Elena Rojas, Revilla, Norma Salinas, Shareva, Yahn Carlos Soto, Trujillo, Raul Tupayachi, Gamarra, Luis Valenzuela, Martinez, Rodolfo Vasquez, Arenas, Jim Vega, Amani, Christian, Ifo, Suspense Averti, Bocko, Yannick, Boundja, Patrick, Ekoungoulou, Romeo, Hockemba, Mireille, Nzala, Donatien, Fofanah, Alusine, Taylor, David, Bañares-de Dios, Guillermo, Cayuela, Luis, la Cerda, Íñigo Granzow de, Macía, Manuel, Stropp, Juliana, Playfair, Maureen, Wortel, Verginia, Gardner, Toby, Muscarella, Robert, Rutishauser, Ervan, Chao, Kuo Jung, Munishi, Pantaleo, Bánki, Olaf, Bongers, Frans, Boot, Rene, Fredriksson, Gabriella, Reitsma, Jan, ter Steege, Hans, van Andel, Tinde, van de Meer, Peter, van der Hout, Peter, van Nieuwstadt, Mark, van Ulft, Bert, Veenendaal, Elmar, Vernimmen, Ronald, Zuidema, Pieter, Zwerts, Joeri, Akite, Perpetra, Bitariho, Robert, Chapman, Colin, Gerald, Eilu, Leal, Miguel, Mucunguzi, Patrick, Abernethy, Katharine, Alexiades, Miguel, Baker, Timothy R., Banda, Karina, Banin, Lindsay, Barlow, Jos, Bennett, Amy, Berenguer, Erika, Berry, Nicholas, Bird, Neil M., Blackburn, George A., Brearley, Francis, Brienen, Roel, Burslem, David, Carvalho, Lidiany, Cho, Percival, Coelho, Fernanda, Collins, Murray, Coomes, David, Cuni-Sanchez, Aida, Dargie, Greta, Dexter, Kyle, Disney, Mat, Draper, Freddie, Duan, Muying, Esquivel-Muelbert, Adriane, Ewers, Robert, Fadrique, Belen, Fauset, Sophie, Feldpausch, Ted R., França, Filipe, Galbraith, David, Gilpin, Martin, Gloor, Emanuel, Grace, John, Hamer, Keith, Harris, David, Jeffery, Kath, Jucker, Tommaso, Kalamandeen, Michelle, Klitgaard, Bente, Levesley, Aurora, Lewis, Simon L., Lindsell, Jeremy, Lopez-Gonzalez, Gabriela, Lovett, Jon, Malhi, Yadvinder, Marthews, Toby, McIntosh, Emma, Melgaço, Karina, Milliken, William, Mitchard, Edward, Moonlight, Peter, Moore, Sam, Morel, Alexandra, Peacock, Julie, Peh, Kelvin S.H., Pendry, Colin, Pennington, R. Toby, de Oliveira Pereira, Luciana, Peres, Carlos, Phillips, Oliver L., Pickavance, Georgia, Pugh, Thomas, Qie, Lan, Riutta, Terhi, Roucoux, Katherine, Ryan, Casey, Sarkinen, Tiina, Valeria, Camila Silva, Spracklen, Dominick, Stas, Suzanne, Sullivan, Martin, Swaine, Michael, Talbot, Joey, Taplin, James, van der Heijden, Geertje, Vedovato, Laura, Willcock, Simon, Williams, Mathew, Alves, Luciana, Loayza, Patricia Alvarez, Arellano, Gabriel, Asa, Cheryl, Ashton, Peter, Asner, Gregory, Brncic, Terry, Brown, Foster, Burnham, Robyn, Clark, Connie, Comiskey, James, Damasco, Gabriel, Davies, Stuart, Di Fiore, Tony, Erwin, Terry, Farfan-Rios, William, Hall, Jefferson, Kenfack, David, Lovejoy, Thomas, Martin, Roberta, Montiel, Olga Martha, Pipoly, John, Pitman, Nigel, Poulsen, John, Primack, Richard, Silman, Miles, Steininger, Marc, Swamy, Varun, Terborgh, John, Thomas, Duncan, Umunay, Peter, Uriarte, Maria, Torre, Emilio Vilanova, Wang, Ophelia, Young, Kenneth, Aymard C., Gerardo A., Hernández, Lionel, Fernández, Rafael Herrera, Ramírez-Angulo, Hirma, Salcedo, Pedro, Sanoja, Elio, Serrano, Julio, Torres-Lezama, Armando, Le, Tinh Cong, Le, Trai Trong, Tran, Hieu Dang, Sub Algemeen Biologie, Sub Animal Behaviour and Cognition, Sub Ecology and Biodiversity, Animal Behaviour and Cognition, Ecology and Biodiversity, Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET), Evolution et Diversité Biologique (EDB), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Ecologie des forêts de Guyane (UMR ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), ANR-10-LABX-0025,CEBA,CEnter of the study of Biodiversity in Amazonia(2010), European Project: 291585,EC:FP7:ERC,ERC-2011-ADG_20110209,T-FORCES(2012), Sub Algemeen Biologie, Sub Animal Behaviour and Cognition, Sub Ecology and Biodiversity, Animal Behaviour and Cognition, Ecology and Biodiversity, Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Universidad Nacional de Tucumán (UNT), Institut de Recherche pour le Développement (IRD [France-Sud]), Forêts et Sociétés (UPR Forêts et Sociétés), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Département Environnements et Sociétés (Cirad-ES), Territoires, Environnement, Télédétection et Information Spatiale (UMR TETIS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Baisie, Michel, Bénédet, Fabrice, Naisso, Petrus, Sist, Plinio, Droissart, Vincent, Rejou-Mechain, Maxime, Gourlet-Fleury, Sylvie, Derroire, Géraldine, Herault, Bruno, Blanc, Lilian, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Jujuy, James Cook University (JCU), CSIRO (Commonwealth Scientific and Industrial Research Organisation), University of Tasmania, CSIRO Tropical Forest Research Centre, Independent Researcher, Environmental Protection Agency (EPA), James Cook University, University of the Sunshine Coast, University of York, Flamingo Land Ltd., Sommersbergseestrasse, Ghent University, Royal Museum for Central Africa - Service of Wood Biology, Université de Liege, Landscape Ecology and Vegetal Production Systems Unit, University of Liege, Evolutionary Biology and Ecology, Royal Museum for Central Africa, Service Evolution Biologique et Ecologie, Belize Foundation for Research and Environmental Education, IBIF, Universidad Autonoma Gabriel Rene Moreno, PROMAB, Museo Noel Kempff, Consultor Independiente, Jardin Botanico Municipal de Santa Cruz, Museo de Historia Natural Noel Kempff Mercado, Forest Management in Bolivia, Universidad Autónoma del Beni Riberalta, Museo de Historia Natural Noel Kempff, Herbario del Sur de Bolivia, Universidad Autónoma del Beni, Conservation International, Universidade Federal do Oeste do Pará, Universidade Federal de Pernambuco (UFPE), Universidade do Estado de Mato Grosso, Universidade do Estado de Mato Grosso (UNEMAT), Projeto TEAM – Manaus, Universidade Federal de Juiz de Fora (UFJF), Universidade Federal do Rio de Janeiro (UFRJ), Projeto Dinâmica Biológica de Fragmentos Florestais, Universidade Federal de Minas Gerais (UFMG), Universidade Estadual de Campinas (UNICAMP), Universidade de São Paulo (USP), National Institute for Space Research (INPE), Universidade Federal de Roraima (UFRR), Universidade Estadual Paulista (Unesp), Carbonozero Consultoria Ambiental, Universidade Federal do Amazonas (UFAM), UERR - Campus Rorainópolis, Universidade Federal do Acre, Instituto Agronômico de Campinas, Universidade Federal do Rio Grande do Sul, Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), Universidade Estadual do Norte Fluminense (UENF), Universidade Federal da Bahia (UFBA), Universidade Federal do Piauí (UFPI), Federal University of Acre, INPA- Instituto Nacional de Pesquisas da Amazônia, UERR - Campus Boa Vista, Universidade Federal do Ceará, Universidade Federal de Campina Grande, Universidade Federal do Para, Ciência e Tecnologia do Acre, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Depto. de Ciências Biológicas, Universidade Federal do Agreste de Pernambuco (UFAPE), Universidade Estadual de Montes Claros, UNEMAT, Universidade Federal de Jataí, Universidade Federal do Pará (UFPA), Universidade Federal de Lavras (UFLA), Museu Goeldi, Instituto Nacional de Pesquisas da Amazônia, Fundação Universidade Fedral de Rondônia - UNIR, INPA- Instituto Nacional de Pesquisas Amazônicas, Instituto Nacional de Pesquisas da Amazônia - Coordenação de Pesquisas em Silvicultura Tropical, Jardim Botânico do Rio de Janeiro, National Institute for Research in Amazonia, Universidade Federal de Roraima (UFRR/PRONAT), Instituto Nacional de Pesquisas da Amazônia/CPBO, Universidade Federal de Santa Catarina (UFSC), Assistência Técnica e Extensão Rural, INPE- Instituto Nacional de Pesquisas Espaciais, Semiarid National Institute (INSA), Universidade de Brasília (UnB), IBAM - Instituto Bem Ambiental, University in Campinas, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Universidade Federal do Vale do São Francisco, Instituto Federal do Espírito Santo (IFES), Grupo MAUA, Humanas e Sociais, Instituto Nacional da Mata Atlântica, RAINFOR-PPBIO, Universidade Federal Rural da Amazônia - UFRA/CAPES, INPA/Max-Planck Project, Serviço Florestal Brasileiro, Universidade Federal Rural de Pernambuco, PUCPR - Pontifícia Universidade Católica do Paraná, Museu Paraense Emilio Goeldi, Universiti Brunei Darussalam, University of Yaounde I, University of Buea, National Herbarium, University of Yaoundé I, University of Yaounde 1, Bioversity International, University of Toronto, Chasse et Pêche (MEFCP), Universidad Católica de la Santísima Concepción, Universidad de La Serena, Chinese Academy of Forestry, Chinese Academy of Sciences, Beijing Forestry University, Red COL-TREE, Corporación COL-TREE, Nuevo Estándar Biotropical NEBIOT SAS, Universidad del Tolima, Universidad de Nariño – Red BST-Col, Territorial Caribe – Red BST-Col, Universidad del Atlantico – Red BST-Col, Universidad Nacional de Colombia - Sede Medellín, Fundacion con Vida, Parques Nacionales Naturales de Colombia – Red BST-Col, Instituto de Investigación de Recursos Biológicos Alexander von Humboldt – Red BST-Col, UNAL, Instituto de Investigación Recursos Biologicos Alexander von Humboldt – Red BST-Col, Herbario 'Joaquín Antonio Uribe' (JAUM) – Red BST-Col, Universidad Nacional de Colombia sede Amazonia, Coltree, Universidad Distrital Francisco José de Caldas – Red BST-Col, Universidad de Tolima, Fundación Orinoquia Biodiversa – Red BST-Col, Universidad Icesi – Red BST-Col, Universidad Nacional de Colombia, Universidad de los Llanos, Servicios Ecoysistemicos y Cambio Climatico (SECC) Fundación Con Vida & Corporación COL-TREE, Universidad del Rosario, Fundacion Ecosistemas Secos de Colombia – Red BST-Col, Universidad de los Andes - ANDES herbarium, Czech Academy of Sciences, Palacky University, Czech University of Life Sciences, Mendel University, World Wide Fund for Nature, Wildlife Conservation Society-DR Congo, Lukuru Wildlife Research Foundation, Université de Kisangani, Université de Kisangani Faculté des Sciences Agronomiques République Démocratique du Congo, Ministère de l'Environnement et Développement Durable, Aarhus University, University of Copenhagen, Escuela Politécnica Nacional del Ecuador, Universidad Central del Ecuador, Universidad Técnica Particular de Loja, Universidad de las Américas, The Field Museum, Facultad de Ingeniería Ambiental, Herbario Nacional del Ecuador, Universidad Regional Amazónica ikiam, Universidad San Francisco de Quito-USFQ, Universidad San Francisco de Quito USFQ, UNC Chapel Hill, University of North Carolina-UNC Chapel Hill, University of Florida, FindingSpecies, Mekelle University, Climate Change and Coffee Forest Forum (ECCCFF), University of Turku, Centre de coopération International en Recherche Agronomique pour le Développement (CIRAD), CNRS, ONF, INRAE, Centre National de la Recherche Scientifique, INRA, Museum national d'histoire naturelle, Université de la Guyane), Environment and Climate, Rougier-Gabon, Agence Nationale des Parcs Nationaux Gabon, Commission of Central African Forests (COMIFAC), des Objectifs de Développement Durable et du Plan d'Affectation des Terres, Institut de Recherche en Ecologie Tropicale (CENAREST) Gabon/Agence Nationale des Parcs Nationaux, Georg-August-University Göttingen, University of Freiburg, University of Hohenheim, Max Planck Institute for Chemistry, Forestry Research Institute of Ghana (FORIG), Forestry Commission of Ghana, Center for International Forestry Research, Iwokrama International Centre for Rainforest Conservation and Development, Guyana Forestry Commission, Utrecht University, Indian Institute of Science, Centre for International Forestry Research (CIFOR), Indonesian Institute of Sciences (LIPI), Indonesian Institute of Science, Forest Research and Development Agency (FORDA), Balitek-KSDA Samboja, University of Florence and MUSE - Museo delle Scienze, Cirad, Hokkaido University, Kyoto University, Forestry Development Authority of the Government of Liberia (FDA), University of Liberia, Sungai Wain Protection Forest, Danum Valley Field Centre, Malaysian Palm Oil Board, Forest Research Centre, Universiti Malaysia Sabah, Sabah Forestry Department, Sarawak Forestry Corporation, Eduardo Mondlane University, Universidad Nacional Autónoma de Nicaragua, University of Abeokuta, Natural History Museum of Norway, University of Oslo, Norwegian University of Life Sciences, Universidad Nacional de la Amazonía Peruana (UNAP), Universidad Nacional de Jaén, Jardin Botanico de Missouri, Andes to Amazon Biodiversity Program, Universidad Nacional de San Agustín de Arequipa, Universidad Nacional de la Amazonía Peruana, Kené - Instituto de Estudios Forestales y Ambientales, Instituto de Investigaciones de la Amazonia Peruana (IIAP), Universidad Nacional Jorge Basadre de Grohmann (UNJBG), Universidad Nacional de San Antonio Abad del Cusco, CIMA, Pontificia Universidad Católica del Perú, Asociacion Bosques Perú, Université Officielle de Bukavu, Université Marien N'Gouabi, Wildlife Conservation Society, Université Marien Ngouabi, Univeriste Marien Ngouabi, The Gola Rainforest National Park, National University of Singapore, Universidad Rey Juan Carlos, Real Jardín Botánico – CSIC, Universidad Autónoma de Madrid, Museo Nacional de Ciencias Naturales (MNCN-CSIC), Centre for Agricultural Research in Suriname (CELOS), Stockholm Environment Institute, Uppsala University, Southern Swedish Forest Research Centre, Conservatoire et Jardin Botanique Geneve, National Chung Hsing University, Sokoine University of Agriculture, Naturalis Biodiversity Center, Forest Ecology and Forest Management Group, Tropenbos International, University of Amsterdam, Bureau Waardenburg BV, Van Hall Larenstein University of Applied Sciences, Van der Hout Forestry Consulting, Plant Ecology and Nature Conservation Group, Data for Sustainability, Makerere University, Mbarara University of Science and Technology (MUST), George Washington University, University of Stirling, University of Kent, University of Leeds, UK Centre of Ecology & Hydrology, Lancaster University, University of Oxford, The Landscapes and Livelihoods Group (TLLG), Overseas Development Institute, Manchester Metropolitan University, University of Aberdeen, University of Exeter, University of Edinburgh, University of Cambridge, University College London, Imperial College, University of Birmingham, University of Plymouth, Royal Botanic Garden Edinburgh, CENAREST & ANPN & Stirling University, School of Biological Sciences, Laurentian University, Royal Botanic Gardens Kew, centre for Conservation Science, UK Centre for Ecology & Hydrology, The Royal Botanic Gardens, University of Dundee, University of Southampton, University of East Anglia, Stirling University, UK Research & Innovation, University of Nottingham, University of Bangor, University of California, Duke University, University of Michigan, Saint Louis Zoo, Harvard University, Arizona State University, Wildlife Conservation Society – Programme Congo, Woods Hole Research Center, The University of Michigan Herbarium, Nicholas School of the Environment, National Park Service, Smithsonian Tropical Research Institute, University of Texas at Austin, Smithsonian Institute, Center for Conservation and Sustainable Development at the Missouri Botanical Garden, Smithsonian Institution Forest Global Earth Observatory (ForestGEO), George Mason University, Missouri Botanical Garden, Broward County Parks and Recreation, Nova Southeastern University, Boston University, Wake Forest University, University of Maryland, San Diego Zoo Institute for Conservation Research, Washington State University, Yale School of Forestry & Environmental Studies, Columbia University, Berkeley, Northern Arizona University, Ci Progress GreenLife, Universidad Nacional Experimental de Guayana, Instituto Venezolano de Investigaciones Científicas (IVIC), Universidad de los Andes, Viet Nature Conservation Centre, CIRAD, and University of Lincoln more...
- Subjects
0106 biological sciences ,Biodiversity ,forêt tropicale ,[SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy ,01 natural sciences ,Carbon sink ,K01 - Foresterie - Considérations générales ,parcelle ,Forest plot ,Global change ,ComputingMilieux_MISCELLANEOUS ,Ecology ,Amazon rainforest ,Environmental resource management ,[SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics ,PE&RC ,Forest plots ,Southeast Asia ,ECOSSISTEMAS FLORESTAIS ,Biosystematiek ,Social research ,Dynamics ,Geography ,AfriTRON ,Écosystème forestier ,Plantenecologie en Natuurbeheer ,P01 - Conservation de la nature et ressources foncières ,Rainforest ,Monitoring ,Evolution ,Climate change ,Plant Ecology and Nature Conservation ,RAINFOR ,[SDV.BID]Life Sciences [q-bio]/Biodiversity ,Grondbezit ,010603 evolutionary biology ,Ecology and Environment ,Grassroots ,Écologie forestière ,[SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems ,Permanent sample plots ,Behavior and Systematics ,Amazonia ,Tropische bossen ,Ecosystemen ,Bosecologie en Bosbeheer ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation ,business.industry ,010604 marine biology & hydrobiology ,Changement de couvert végétal ,Water Resources Management ,Forest Ecology and Forest Management ,biodiversité forestière ,Wildlife Ecology and Conservation ,Africa ,Biosystematics ,Couvert forestier ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,business ,Species richness - Abstract
Made available in DSpace on 2021-06-25T11:16:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Agence Nationale Des Parcs Nationaux Centre for International Forestry Research Departamento Administrativo de Ciencia, Tecnología e Innovación (COLCIENCIAS) David and Lucile Packard Foundation European Space Agency Leverhulme Trust Gordon and Betty Moore Foundation Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundação de Amparo à Pesquisa do Estado de Goiás European Research Council Belgian Federal Science Policy Office Vlaamse Interuniversitaire Raad Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) National Science Foundation Natural Environment Research Council Royal Society National Geographic Society Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Tropical forests are the most diverse and productive ecosystems on Earth. While better understanding of these forests is critical for our collective future, until quite recently efforts to measure and monitor them have been largely disconnected. Networking is essential to discover the answers to questions that transcend borders and the horizons of funding agencies. Here we show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots. We review the major scientific discoveries of this work and show how this process is changing tropical forest science. Our core approach involves linking long-term grassroots initiatives with standardized protocols and data management to generate robust scaled-up results. By connecting tropical researchers and elevating their status, our Social Research Network model recognises the key role of the data originator in scientific discovery. Conceived in 1999 with RAINFOR (South America), our permanent plot networks have been adapted to Africa (AfriTRON) and Southeast Asia (T-FORCES) and widely emulated worldwide. Now these multiple initiatives are integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. Collectively these are transforming understanding of tropical forests and their biospheric role. Together we have discovered how, where and why forest carbon and biodiversity are responding to climate change, and how they feedback on it. This long-term pan-tropical collaboration has revealed a large long-term carbon sink and its trends, as well as making clear which drivers are most important, which forest processes are affected, where they are changing, what the lags are, and the likely future responses of tropical forests as the climate continues to change. By leveraging a remarkably old technology, plot networks are sparking a very modern revolution in tropical forest science. In the future, humanity can benefit greatly by nurturing the grassroots communities now collectively capable of generating unique, long-term understanding of Earth's most precious forests. Resumen: Los bosques tropicales son los ecosistemas más diversos y productivos del mundo y entender su funcionamiento es crítico para nuestro futuro colectivo. Sin embargo, hasta hace muy poco, los esfuerzos para medirlos y monitorearlos han estado muy desconectados. El trabajo en redes es esencial para descubrir las respuestas a preguntas que trascienden las fronteras y los plazos de las agencias de financiamiento. Aquí mostramos cómo una comunidad global está respondiendo a los desafíos de la investigación en ecosistemas tropicales a través de diversos equipos realizando mediciones árbol por árbol en miles de parcelas permanentes de largo plazo. Revisamos los descubrimientos más importantes de este trabajo y discutimos cómo este proceso está cambiando la ciencia relacionada a los bosques tropicales. El enfoque central de nuestro esfuerzo implica la conexión de iniciativas locales de largo plazo con protocolos estandarizados y manejo de datos para producir resultados que se puedan trasladar a múltiples escalas. Conectando investigadores tropicales, elevando su posición y estatus, nuestro modelo de Red Social de Investigación reconoce el rol fundamental que tienen, para el descubrimiento científico, quienes generan o producen los datos. Concebida en 1999 con RAINFOR (Suramérica), nuestras redes de parcelas permanentes han sido adaptadas en África (AfriTRON) y el sureste asiático (T-FORCES) y ampliamente replicadas en el mundo. Actualmente todas estas iniciativas están integradas a través de la ciber-infraestructura de ForestPlots.net, conectando colegas de 54 países en 24 redes diferentes de parcelas. Colectivamente, estas redes están transformando nuestro conocimiento sobre los bosques tropicales y el rol de éstos en la biósfera. Juntos hemos descubierto cómo, dónde y porqué el carbono y la biodiversidad de los bosques tropicales está respondiendo al cambio climático y cómo se retroalimentan. Esta colaboración pan-tropical de largo plazo ha expuesto un gran sumidero de carbono y sus tendencias, mostrando claramente cuáles son los factores más importantes, qué procesos se ven afectados, dónde ocurren los cambios, los tiempos de reacción y las probables respuestas futuras mientras el clima continúa cambiando. Apalancando lo que realmente es una tecnología antigua, las redes de parcelas están generando una verdadera y moderna revolución en la ciencia tropical. En el futuro, la humanidad puede beneficiarse enormemente si se nutren y cultivan comunidades de investigadores de base, actualmente con la capacidad de generar información única y de largo plazo para entender los que probablemente son los bosques más preciados de la tierra. Resumo: Florestas tropicais são os ecossistemas mais diversos e produtivos da Terra. Embora uma boa compreensão destas florestas seja crucial para o nosso futuro coletivo, até muito recentemente os esforços de medições e monitoramento foram amplamente desconexos. É essencial formarmos redes para obtermos respostas que transcendem fronteiras e horizontes de agências financiadoras. Neste estudo nós mostramos como uma comunidade global está respondendo aos desafios da pesquisa de ecossistemas tropicais, com equipes diversas medindo florestas, árvore por árvore, em milhares de parcelas monitoradas à longo prazo. Nós revisamos as maiores descobertas científicas deste trabalho, e mostramos também como este processo está mudando a ciência de florestas tropicais. Nossa abordagem principal envolve unir iniciativas de base a protocolos padronizados e gerenciamento de dados a fim de gerar resultados robustos em escalas ampliadas. Ao conectar pesquisadores tropicais e elevar seus status, nosso modelo de Rede de Pesquisa Social reconhece o papel-chave do produtor dos dados na descoberta científica. Concebida em 1999 com o RAINFOR (América do Sul), nossa rede de parcelas permanentes foi adaptada para África (AfriTRON) e Sudeste asiático (T-FORCES), e tem sido extensamente reproduzida em todo o mundo. Agora estas múltiplas iniciativas estão integradas através de uma infraestrutura cibernética do ForestPlots.net, conectando colegas de 54 países de 24 redes de parcelas. Estas iniciativas estão transformando coletivamente o entendimento das florestas tropicais e seus papéis na biosfera. Juntos nós descobrimos como, onde e por que o carbono e a biodiversidade da floresta estão respondendo às mudanças climáticas, e seus efeitos de retroalimentação. Esta duradoura colaboração pantropical revelou um grande sumidouro de carbono persistente e suas tendências, assim como tem evidenciado quais direcionadores são mais importantes, quais processos florestais são mais afetados, onde eles estão mudando, seus atrasos no tempo de resposta, e as prováveis respostas das florestas tropicais conforme o clima continua a mudar. Dessa forma, aproveitando uma notável tecnologia antiga, redes de parcelas acendem faíscas de uma moderna revolução na ciência das florestas tropicais. No futuro a humanidade pode se beneficiar incentivando estas comunidades basais que agora são coletivamente capazes de gerar conhecimentos únicos e duradouros sobre as florestas mais preciosas da Terra. Résume: Les forêts tropicales sont les écosystèmes les plus diversifiés et les plus productifs de la planète. Si une meilleure compréhension de ces forêts est essentielle pour notre avenir collectif, jusqu'à tout récemment, les efforts déployés pour les mesurer et les surveiller ont été largement déconnectés. La mise en réseau est essentielle pour découvrir les réponses à des questions qui dépassent les frontières et les horizons des organismes de financement. Nous montrons ici comment une communauté mondiale relève les défis de la recherche sur les écosystèmes tropicaux avec diverses équipes qui mesurent les forêts arbre après arbre dans de milliers de parcelles permanentes. Nous passons en revue les principales découvertes scientifiques de ces travaux et montrons comment ce processus modifie la science des forêts tropicales. Notre approche principale consiste à relier les initiatives de base à long terme à des protocoles standardisés et une gestion de données afin de générer des résultats solides à grande échelle. En reliant les chercheurs tropicaux et en élevant leur statut, notre modèle de réseau de recherche sociale reconnaît le rôle clé de l'auteur des données dans la découverte scientifique. Conçus en 1999 avec RAINFOR (Amérique du Sud), nos réseaux de parcelles permanentes ont été adaptés à l'Afrique (AfriTRON) et à l'Asie du Sud-Est (T-FORCES) et largement imités dans le monde entier. Ces multiples initiatives sont désormais intégrées via l'infrastructure ForestPlots.net, qui relie des collègues de 54 pays à travers 24 réseaux de parcelles. Ensemble, elles transforment la compréhension des forêts tropicales et de leur rôle biosphérique. Ensemble, nous avons découvert comment, où et pourquoi le carbone forestier et la biodiversité réagissent au changement climatique, et comment ils y réagissent. Cette collaboration pan-tropicale à long terme a révélé un important puits de carbone à long terme et ses tendances, tout en mettant en évidence les facteurs les plus importants, les processus forestiers qui sont affectés, les endroits où ils changent, les décalages et les réactions futures probables des forêts tropicales à mesure que le climat continue de changer. En tirant parti d'une technologie remarquablement ancienne, les réseaux de parcelles déclenchent une révolution très moderne dans la science des forêts tropicales. À l'avenir, l'humanité pourra grandement bénéficier du soutien des communautés de base qui sont maintenant collectivement capables de générer une compréhension unique et à long terme des forêts les plus précieuses de la Terre. Abstrak: Hutan tropika adalah di antara ekosistem yang paling produktif dan mempunyai kepelbagaian biodiversiti yang tinggi di seluruh dunia. Walaupun pemahaman mengenai hutan tropika amat penting untuk masa depan kita, usaha-usaha untuk mengkaji dan mengawas hutah-hutan tersebut baru sekarang menjadi lebih diperhubungkan. Perangkaian adalah sangat penting untuk mencari jawapan kepada soalan-soalan yang menjangkaui sempadan dan batasan agensi pendanaan. Di sini kami menunjukkan bagaimana sebuah komuniti global bertindak balas terhadap cabaran penyelidikan ekosistem tropika melalui penglibatan pelbagai kumpulan yang mengukur hutan secara pokok demi pokok dalam beribu-ribu plot jangka panjang. Kami meninjau semula penemuan saintifik utama daripada kerja ini dan menunjukkan bagaimana proses ini sedang mengubah bidang sains hutan tropika. Teras pendekatan kami memberi tumpuan terhadap penghubungan inisiatif akar umbi jangka panjang dengan protokol standar serta pengurusan data untuk mendapatkan hasil skala besar yang kukuh. Dengan menghubungkan penyelidik-penyelidik tropika dan meningkatkan status mereka, model Rangkaian Penyelidikan Sosial kami mengiktiraf kepentingan peranan pengasas data dalam penemuan saintifik. Bermula dengan pengasasan RAINFOR (Amerika Selatan) pada tahun 1999, rangkaian-rangkaian plot kekal kami kemudian disesuaikan untuk Afrika (AfriTRON) dan Asia Tenggara (T-FORCES) dan selanjutnya telah banyak dicontohi di seluruh dunia. Kini, inisiatif-inisiatif tersebut disepadukan melalui infrastruktur siber ForestPlots.net yang menghubungkan rakan sekerja dari 54 negara di 24 buah rangkaian plot. Secara kolektif, rangkaian ini sedang mengubah pemahaman tentang hutan tropika dan peranannya dalam biosfera. Kami telah bekerjasama untuk menemukan bagaimana, di mana dan mengapa karbon serta biodiversiti hutan bertindak balas terhadap perubahan iklim dan juga bagaimana mereka saling bermaklum balas. Kolaborasi pan-tropika jangka panjang ini telah mendedahkan sebuah sinki karbon jangka panjang serta arah alirannya dan juga menjelaskan pemandu-pemandu perubahan yang terpenting, di mana dan bagaimana proses hutan terjejas, masa susul yang ada dan kemungkinan tindakbalas hutan tropika pada perubahan iklim secara berterusan di masa depan. Dengan memanfaatkan pendekatan lama, rangkaian plot sedang menyalakan revolusi yang amat moden dalam sains hutan tropika. Pada masa akan datang, manusia sejagat akan banyak mendapat manfaat jika memupuk komuniti-komuniti akar umbi yang kini berkemampuan secara kolektif menghasilkan pemahaman unik dan jangka panjang mengenai hutan-hutan yang paling berharga di dunia. Instituto de Ecología Regional (IER) Universidad Nacional de Tucumán (UNT) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Facultad de Ciencias Agrarias Universidad Nacional de Jujuy James Cook University (JCU) CSIRO (Commonwealth Scientific and Industrial Research Organisation) School of Land & Food University of Tasmania CSIRO Tropical Forest Research Centre Independent Researcher Environmental Protection Agency (EPA) Centre for Tropical Environmental and Sustainability Science (TESS) College of Marine and Environmental Sciences James Cook University Centre for Tropical Environmental and Sustainability Science College of Science and Engineering James Cook University University of the Sunshine Coast University of York Flamingo Land Ltd. Sommersbergseestrasse Ghent University CAVElab Ghent University Royal Museum for Central Africa - Service of Wood Biology Isotope Bioscience Laboratory-ISOFYS Ghent University Gembloux Agro-Bio Tech Université de Liege Landscape Ecology and Vegetal Production Systems Unit CAVElab Computational & Applied Vegetation Ecology Ghent University Tropical Forestry Forest Resources Management Gembloux Agro-Bio Tech University of Liege Université Libre de Bruxelles (ULB) Evolutionary Biology and Ecology Royal Museum for Central Africa Royal Museum for Central Africa Ghent University Department of Environment Ghent University Service Evolution Biologique et Ecologie Belize Foundation for Research and Environmental Education IBIF Museo de Historia Natural Noel Kempff Mercado Universidad Autonoma Gabriel Rene Moreno PROMAB Museo Noel Kempff Consultor Independiente Jardin Botanico Municipal de Santa Cruz Museo de Historia Natural Noel Kempff Mercado Forest Management in Bolivia Universidad Autónoma del Beni Riberalta Museo de Historia Natural Noel Kempff Herbario del Sur de Bolivia Universidad Autónoma del Beni Conservation International Instituto de Biodiversidade e Floresta Universidade Federal do Oeste do Pará Universidade Federal de Pernambuco Universidade do Estado de Mato Grosso Universidade do Estado de Mato Grosso (UNEMAT) Projeto TEAM – Manaus Universidade Federal de Juiz de Fora (UFJF) Universidade Federal do Rio de Janeiro Instituto Nacional de Pesquisas da Amazônia Projeto Dinâmica Biológica de Fragmentos Florestais Departamento de Genética Ecologia e Evolução Universidade Federal de Minas Gerais Universidade Estadual de Campinas Laboratório de Ecologia de Comunidades e Funcionamento de Ecossistemas-ECoFERP Departamento de Biologia Faculdade de Filosofia Ciências e Letras USP National Institute for Space Research (INPE) Universidade Federal de Roraima (UFRR) UNESP - São Paulo State University Carbonozero Consultoria Ambiental Departamento de Biologia Universidade Federal do Amazonas (UFAM) Centro de Energia Nuclear na Agricultura Universidade de São Paulo UERR - Campus Rorainópolis Universidade Federal do Acre Instituto Agronômico de Campinas Universidade Federal do Rio Grande do Sul Embrapa Universidade Estadual do Norte Fluminense (UENF) Universidade Federal da Bahia (UFBA) Instituto de Biologia Universidade Estadual de Campinas Universidade Federal do Piauí (UFPI) Botany and Plant Ecology Laboratory Federal University of Acre INPA- Instituto Nacional de Pesquisas da Amazônia UERR - Campus Boa Vista Universidade Federal do Ceará Universidade Federal de Campina Grande Universidade Federal do Para Núcleo de Estudos e Pesquisas Ambientais Universidade Estadual de Campinas Instituto Federal de Educação Ciência e Tecnologia do Acre Instituto de Pesquisas Jardim Botânico do Rio de Janeiro Universidade Federal do Oeste do Pará UEFS Depto. de Ciências Biológicas Universidade Federal do Agreste de Pernambuco (UFAPE) Universidade Estadual de Montes Claros FFCLRP-USP/Br UNEMAT Universidade Federal de Jataí Universidade Federal do Pará Instituto de Ciências Biológicas Universidade de Campinas Universidade Federal de Lavras (UFLA) Museu Goeldi Embrapa Amazônia Oriental Instituto Nacional de Pesquisas da Amazônia UFMG - Universidade Federal de Minas Gerais Fundação Universidade Fedral de Rondônia - UNIR INPA- Instituto Nacional de Pesquisas Amazônicas Instituto Nacional de Pesquisas da Amazônia - Coordenação de Pesquisas em Silvicultura Tropical Jardim Botânico do Rio de Janeiro National Institute for Research in Amazonia Universidade Federal de Roraima (UFRR/PRONAT) Universidade Estadual de Campinas/UNICAMP Instituto Nacional de Pesquisas da Amazônia/CPBO Universidade Federal de Santa Catarina (UFSC) INCAPER- Instituto Capixaba de Pesquisa Assistência Técnica e Extensão Rural INPE- Instituto Nacional de Pesquisas Espaciais Universidade de São Paulo Instituto de Biociências Universidade Estadual Paulista Semiarid National Institute (INSA) Universidade de Brasília Departamento de Engenharia Florestal IBAM - Instituto Bem Ambiental Universidade do Estado de Mato Grosso Campus de Nova Xavantina University in Campinas Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF) LMF Instituto Nacional de Pesquisas da Amazônia Universidade Federal do Vale do São Francisco USP - University of São Paulo Instituto Federal do Espírito Santo (IFES) INPA - Instituto Nacional de Pesquisas da Amazônia Grupo MAUA Universidade Federal de Mato Grosso Instituto de Ciências Naturais Humanas e Sociais Instituto Nacional da Mata Atlântica RAINFOR-PPBIO Universidade Federal Rural da Amazônia - UFRA/CAPES Universidade Federal do Amazonas (UFAM) INPA/Max-Planck Project EMBRAPA- Empresa Brasileira de Pesquisa Agropecuária (Amazônia Oriental) Serviço Florestal Brasileiro Museu Universitário Universidade Federal do Acre Universidade Federal Rural de Pernambuco PUCPR - Pontifícia Universidade Católica do Paraná Museu Paraense Emilio Goeldi Universiti Brunei Darussalam Environmental and Life Sciences Faculty of Science Universiti Brunei Darussalam Institute for Biodiversity and Environmental Research Universiti Brunei Darussalam Plant Systematic and Ecology Laboratory Department of Biology Higher Teachers’ Training College University of Yaounde I Faculty of Science Department of Botany and Plant Physiology University of Buea Faculty of Science Department of Plant Science University of Buea National Herbarium Plant Systematics and Ecology Laboratory Higher Teachers’ Training College University of Yaoundé I Department of Plant Biology Faculty of Sciences University of Yaounde 1 Bioversity International Faculty of Forestry University of Toronto Ministère des Eaux Forêts Chasse et Pêche (MEFCP) Universidad Católica de la Santísima Concepción Universidad de La Serena Research Institute of Tropical Forestry Chinese Academy of Forestry Kunming Institute of Botany Chinese Academy of Sciences Beijing Forestry University Universidad Nacional Abierta y a Distancia Red COL-TREE Corporación COL-TREE Nuevo Estándar Biotropical NEBIOT SAS Universidad del Tolima Asociación GAICA Universidad de Nariño – Red BST-Col Parques Nacionales Naturales Territorial Caribe – Red BST-Col Universidad del Atlantico – Red BST-Col Departamento de Ciencias Forestales Universidad Nacional de Colombia - Sede Medellín Socioecosistemas y Clima Sostenible Fundacion con Vida Parques Nacionales Naturales de Colombia – Red BST-Col Instituto de Investigación de Recursos Biológicos Alexander von Humboldt – Red BST-Col UNAL Instituto de Investigación Recursos Biologicos Alexander von Humboldt – Red BST-Col Fundación Jardín Botánico de Medellín Herbario “Joaquín Antonio Uribe” (JAUM) – Red BST-Col Universidad Nacional de Colombia sede Amazonia Coltree Facultad del Medio Ambiente y Recursos Naturales Universidad Distrital Francisco José de Caldas – Red BST-Col Universidad de Tolima Fundación Orinoquia Biodiversa – Red BST-Col Departamento de Biología Facultad de Ciencias Naturales Universidad Icesi – Red BST-Col Instituto de Ciencias Naturales Universidad Nacional de Colombia Universidad de los Llanos Servicios Ecoysistemicos y Cambio Climatico (SECC) Fundación Con Vida & Corporación COL-TREE Universidad del Rosario Fundacion Ecosistemas Secos de Colombia – Red BST-Col Universidad de los Andes - ANDES herbarium Institute of Botany Czech Academy of Sciences Palacky University Czech University of Life Sciences Mendel University World Wide Fund for Nature Wildlife Conservation Society-DR Congo Lukuru Wildlife Research Foundation Université de Kisangani Faculté des Sciences Laboratoire d'écologie et aménagement forestier Université de Kisangani Université de Kisangani Faculté des Sciences Agronomiques République Démocratique du Congo Ministère de l'Environnement et Développement Durable Aarhus University University of Copenhagen Escuela Politécnica Nacional del Ecuador Herbario Alfredo Paredes (QAP) Universidad Central del Ecuador Universidad Técnica Particular de Loja Grupo de Investigación en Biodiversidad Medio Ambiente y Salud-BIOMAS Universidad de las Américas, Campus Queri Keller Science Action Center The Field Museum, 1400 South Lake Shore Dr. Universidad Estatal Amazónica Facultad de Ingeniería Ambiental Universidad Tecnica del Norte Herbario Nacional del Ecuador Grupo de Ecosistemas Tropicales y Cambio Global Universidad Regional Amazónica ikiam Colegio de Ciencias Biológicas y Ambientales COCIBA & Extensión Galápagos Universidad San Francisco de Quito-USFQ Herbario de Botánica Económica del Ecuador QUSF Universidad San Francisco de Quito USFQ Galapagos Science Center USFQ UNC Chapel Hill University of North Carolina-UNC Chapel Hill University of Florida FindingSpecies Mekelle University Environment Climate Change and Coffee Forest Forum (ECCCFF) University of Turku Centre de coopération International en Recherche Agronomique pour le Développement (CIRAD) CNRS ONF INRAE Centre National de la Recherche Scientifique AMAP Univ Montpellier IRD CNRS CIRAD INRA Forêts et Sociétés (F&S) Centre de coopération International en Recherche Agronomique pour le Développement (CIRAD) Departement Hommes Natures Societes Museum national d'histoire naturelle INRA Cirad UMR Ecologie des Forêts de Guyane (AgroparisTech CNRS INRAE Université des Antilles Université de la Guyane) Ministry of Forests Seas Environment and Climate Rougier-Gabon Agence Nationale des Parcs Nationaux Gabon Commission of Central African Forests (COMIFAC) Agence Nationale des Parcs Nationaux Ministère des Forêts des Eaux de la Mer de l'Environnement Chargé du Plan Climat des Objectifs de Développement Durable et du Plan d'Affectation des Terres Institut de Recherche en Ecologie Tropicale (CENAREST) Gabon/Agence Nationale des Parcs Nationaux Georg-August-University Göttingen University of Freiburg Institute of Botany University of Hohenheim Max Planck Institute for Chemistry Forestry Research Institute of Ghana (FORIG) Mensuration Unit Forestry Commission of Ghana Center for International Forestry Research Iwokrama International Centre for Rainforest Conservation and Development Guyana Forestry Commission Utrecht University Centre for Sustainable Technologies Indian Institute of Science Centre for International Forestry Research (CIFOR) Herbarium Borgoriense Indonesian Institute of Sciences (LIPI) Indonesian Institute of Science Forest Research and Development Agency (FORDA) Balitek-KSDA Samboja University of Florence and MUSE - Museo delle Scienze Cirad Hokkaido University Graduate School of Agriculture Kyoto University Forestry Development Authority of the Government of Liberia (FDA) University of Liberia Sungai Wain Protection Forest South East Asia Rainforest Research Partnership Danum Valley Field Centre Malaysian Palm Oil Board Sabah Forestry Department Forest Research Centre Universiti Malaysia Sabah Sabah Forestry Department Sarawak Forestry Corporation Eduardo Mondlane University Herbarium UNAN-Leon Universidad Nacional Autónoma de Nicaragua University of Abeokuta Natural History Museum of Norway University of Oslo Norwegian University of Life Sciences Universidad Nacional de la Amazonía Peruana (UNAP) Universidad Nacional de Jaén Jardin Botanico de Missouri Andes to Amazon Biodiversity Program Universidad Nacional de San Agustín de Arequipa Facultad de Ciencias Biológicas Universidad Nacional de la Amazonía Peruana Kené - Instituto de Estudios Forestales y Ambientales Instituto de Investigaciones de la Amazonia Peruana (IIAP) Universidad Nacional Jorge Basadre de Grohmann (UNJBG) Universidad Nacional de San Antonio Abad del Cusco Centro de Conservación Investigación y Manejo CIMA Pontificia Universidad Católica del Perú Asociacion Bosques Perú Université Officielle de Bukavu Université Marien N'Gouabi Wildlife Conservation Society Ecole Nationale Supérieure d'Agronomie et de Foresterie Université Marien Ngouabi Univeriste Marien Ngouabi The Gola Rainforest National Park Department of Geography National University of Singapore Departamento de Biología y Geología Física y Química inorgánica Universidad Rey Juan Carlos Real Jardín Botánico – CSIC Departamento de Biología Área de Botánica Universidad Autónoma de Madrid Museo Nacional de Ciencias Naturales (MNCN-CSIC) Centre for Agricultural Research in Suriname (CELOS) Stockholm Environment Institute Department of Plant Ecology and Evolution Uppsala University Southern Swedish Forest Research Centre InfoFlora Conservatoire et Jardin Botanique Geneve National Chung Hsing University Sokoine University of Agriculture Naturalis Biodiversity Center Wageningen University Forest Ecology and Forest Management Group Tropenbos International Institute for Biodiversity and Ecosystem Dynamics University of Amsterdam Bureau Waardenburg BV Van Hall Larenstein University of Applied Sciences Van der Hout Forestry Consulting Utrecht University, Domplein 29 Wageningen University Plant Ecology and Nature Conservation Group Data for Sustainability Department of Zoology Entomology & Fisheries Sciences Makerere University The Institute of Tropical Forest Conservation (ITFC) Mbarara University of Science and Technology (MUST) George Washington University Makerere University Department of Forestry Biodiversity and Tourism Makerere University University of Stirling University of Kent School of Geography University of Leeds UK Centre of Ecology & Hydrology Lancaster University University of Oxford The Landscapes and Livelihoods Group (TLLG) Overseas Development Institute Manchester Metropolitan University University of Aberdeen University of Exeter School of GeoSciences University of Edinburgh University of Cambridge Department of Environment and Geography University of York Department of Geography University College London Imperial College School of Geography Earth & Environmental Sciences Birmingham Institute of Forest Research University of Birmingham University of Plymouth Geography College of Life and Environmental Sciences University of Exeter Lancaster Environment Centre Lancaster University University of Edinburgh School of Biology University of Leeds Royal Botanic Garden Edinburgh CENAREST & ANPN & Stirling University University of Bristol School of Biological Sciences Department of Plant Sciences University of Cambridge Living with Lake Centre Laurentian University Royal Botanic Gardens Kew The Royal Society for the Protection of Birds centre for Conservation Science Environmental Change Institute School of Geography and the Environment University of Oxford UK Centre for Ecology & Hydrology School of Geography and the Environment University of Oxford The Royal Botanic Gardens Department of Geography and Environmental Science University of Dundee School of Biological Sciences University of Southampton University of East Anglia Stirling University School of Earth and Environment University of Leeds Department of Plant & Soil Science School of Biological Sciences University of Aberdeen, Cruickshank Building Institute for Transport Studies University of Leeds UK Research & Innovation University of Nottingham University of Bangor Center for Tropical Research Institute of the Environment and Sustainability University of California Center for Tropical Conservation Nicholas School of the Environment Duke University Ecology and Evolutionary Biology University of Michigan Saint Louis Zoo Department of Organismic and Evolutionary Biology Harvard University Center for Global Discovery and Conservation Science Arizona State University Wildlife Conservation Society – Programme Congo Woods Hole Research Center The University of Michigan Herbarium Nicholas School of the Environment National Park Service University of California ForestGEO Smithsonian Tropical Research Institute University of Texas at Austin Smithsonian Institute Washington University in Saint Louis Center for Conservation and Sustainable Development at the Missouri Botanical Garden Smithsonian Tropical Research Institute Smithsonian Institution Forest Global Earth Observatory (ForestGEO) Forest Global Earth Observatory (ForestGEO) Smithsonian Tropical Research Institute George Mason University Missouri Botanical Garden Broward County Parks and Recreation Nova Southeastern University Science and Education The Field Museum Department of Biology Boston University Wake Forest University Department of Geographical Sciences University of Maryland San Diego Zoo Institute for Conservation Research Biology Department Washington State University Yale School of Forestry & Environmental Studies Columbia University Department of Environmental Science Policy and Management University of California Berkeley School of Earth Sciences and Environmental Sustainability Northern Arizona University Department of Geography and the Environment University of Texas at Austin UNELLEZ-Guanare Programa de Ciencias del Agro y el Mar Herbario Universitario (PORT) Ci Progress GreenLife Universidad Nacional Experimental de Guayana Instituto Venezolano de Investigaciones Científicas (IVIC) Universidad de los Andes Viet Nature Conservation Centre CIRAD School of Life Sciences University of Lincoln UNESP - São Paulo State University Instituto de Biociências Universidade Estadual Paulista Gordon and Betty Moore Foundation: 1656 FAPESP: 2012/51509-8 FAPESP: 2012/51872-5 Fundação de Amparo à Pesquisa do Estado de Goiás: 2017/10267000329 European Research Council: 291585 Gordon and Betty Moore Foundation: 5349 European Research Council: 758873 Belgian Federal Science Policy Office: BR/132/A1/AFRIFORD Belgian Federal Science Policy Office: BR/143/A3/HERBAXYLAREDD Vlaamse Interuniversitaire Raad: CD2018TEA459A103 CNPq: CNPq/PPBio/457602/2012-0 National Science Foundation: DEB 1754647 Natural Environment Research Council: E/M0022021/1 Royal Society: ICA/R1/180100 Natural Environment Research Council: NE/D005590/1 European Research Council: NE/F005806/1 Natural Environment Research Council: NE/F005806/1 FAPESP: NE/K016431/1 Natural Environment Research Council: NE/N004655/1 FAPESP: NE/N012542/1 Royal Society: NE/P008755/1 FAPESP: NE/S011811/1 National Geographic Society: NE/T01279X/1 CNPq: PELD/441244/2016-5 Belgian Federal Science Policy Office: SD/AR/01A/COBIMFO more...
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- 2021
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32. Learning-Based Approaches for Forward Kinematic Modeling of Continuum Manipulators
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Achille Melingui, Othman Lakhal, I. Mahamat Loutfi, F. Biya Motto, Rochdi Merzouki, A. H. Bouyom Boutchouang, Department of Physic’s, Faculty of Sciences, University of Yaounde I, Yaounde 8390, Department of Electrical and Telecommunications Engineering, ENSP, University of Yaounde I, Centre de Recherche en Informatique, Signal et Automatique de Lille - UMR 9189 (CRIStAL), and Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS) more...
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0209 industrial biotechnology ,Computer science ,Continuum (topology) ,business.industry ,020208 electrical & electronic engineering ,02 engineering and technology ,Kinematics ,Motion capture ,[INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation ,Support vector machine ,020901 industrial engineering & automation ,Control and Systems Engineering ,Multilayer perceptron ,[INFO.INFO-AU]Computer Science [cs]/Automatic Control Engineering ,Kinematic modeling ,0202 electrical engineering, electronic engineering, information engineering ,[INFO.INFO-SY]Computer Science [cs]/Systems and Control [cs.SY] ,Robot ,[INFO.INFO-RB]Computer Science [cs]/Robotics [cs.RO] ,Learning based ,Artificial intelligence ,business ,ComputingMilieux_MISCELLANEOUS - Abstract
Forward kinematic model (FKM) is an essential module in the control law design of manipulator robots. Unlike rigid manipulators where it can be easily established, it remains a real challenge for their continuum counterparts. Model-based and learning-based approaches are commonly used for the forward kinematic modeling of continuum manipulators. Model-based approaches generally lead to imprecise FKM models due to several modeling assumptions, while learning-based approaches generally yield acceptable performance. However, the choice of an appropriate learning model remains a challenging task. In the framework of the forward kinematic modeling of continuum manipulators, this paper proposes an experimental and structural comparative study of the commonly used learning models, namely the multilayer perceptron (MLP), radial based functions (RBF), support vector regression (SVR), and Co-Active adaptive neuro-fuzzy inference system (CANFIS). The Compact Bionic Handling Assistant (CBHA) robot is used as an experimental platform and the predictions of the different learning models are compared respectively to a high precision motion capture system. According to the comparative study, we noted better accuracy for SVRs, rapid convergence for RBFs, and a good compromise between learning time and accuracy for MLPs. CANFIS offers accuracy close to that of SVRs but with much shorter learning time. more...
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- 2020
33. Modelling and experimental determination of thermal properties of local wet building
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Damfeu, Jean-Claude, Meukam, Pierre, Jannot, Yves, Wati, Emmanuel, National Advanced School of Engineering (University of Yaounde I), Laboratoire Énergies et Mécanique Théorique et Appliquée (LEMTA ), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Environmental Energy Technologies Laboratory, University of Yaounde I, and Université de Yaoundé I more...
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Water content ,[SPI]Engineering Sciences [physics] ,Composite wet porous materials ,Thermal properties ,Energy saving ,Transient method - Abstract
International audience; One of the greatest challenges in the construction sector throughout the world is the development of appropriate building materials that can reduce energy consumption. In this work, an investigation on the thermophysical properties of three wet composite building materials was carried out: the black pouzzolan, the red pouzzolan and sand cinder blocks. Experimental measurements were carried out on these three materials each with a water contentranging between 0 and 5%.Using an asymmetrical hot plate device, a transient method, the thermal effusivity and volumetric heat capacity were estimated experimentally with respect to water content. With the values of the mass specific heat capacity of pouzzolans, sand and cement separately measured by the Differential Scanning Calorimeter (DSC) method, the values of the volumetric heat capacity of these composite materials were evaluated according to their water content calculated from the theoretical developed model. The results obtained are in good agreement with those determined experimentally with the asymmetrical hot plate method (maximum standard deviations 5%). Results reveal that the thermal conductivity of red pouzzolan cinder blocks (e.g. lambda = 0.503 W m(-1) K-1 at 0% water content) and of black pouzzolan cinder blocks (e.g. lambda = 0.549 W m(-1) K-1 at 0% water content) are lower than that of sand cinder blocks (e.g. lambda = 0.875 W m(-1) K-1 at 0% water content). Results also show that pouzzolans cinder blocks have higher volumetric heat capacity than sand cinder blocks. These results further confirm that blocks based on pouzzolans are better insulator materials than sand blocks (usually uses) and can contribute significantly to the energy saving and thus reduce the GHG emission in the air-conditioning building. more...
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- 2017
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34. Efficient scalable sensor node placement algorithm for fixed target coverage applications of wireless sensor networks
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Wahabou Abdou, Arouna Ndam Njoya, Chris Thron, Albert Dipanda, Nukenine Siri Lawrencia Konje, Emmanuel Tonye, Jordan Barry, Institut Universitaire de Technologie - Ngaoundéré (IUT Ngaoundéré), Université de Ngaoundéré/University of Ngaoundéré [Cameroun] (UN), Department of Mathematics [Texas] (TAMU), Texas A&M University [College Station], Laboratoire Electronique, Informatique et Image [UMR6306] (Le2i), Université de Bourgogne (UB)-École Nationale Supérieure d'Arts et Métiers (ENSAM), Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), National Advanced School of Engineering (University of Yaounde I), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Arts et Métiers (ENSAM), HESAM Université (HESAM)-HESAM Université (HESAM)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, University Institute of Technology, University of Ngaoundéré, University of Ngaoundere, Department of Mathematics [Texas] ( TAMU ), Laboratoire Electronique, Informatique et Image ( Le2i ), Université de Bourgogne ( UB ) -AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique ( CNRS ), and National Advanced School of Engineering ( University of Yaounde I ) more...
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Brooks–Iyengar algorithm ,[ INFO ] Computer Science [cs] ,annealing schedule ,Computer science ,Computation ,Distributed computing ,Real-time computing ,[INFO.INFO-DS]Computer Science [cs]/Data Structures and Algorithms [cs.DS] ,sensor placement ,02 engineering and technology ,01 natural sciences ,Industrial and Manufacturing Engineering ,0202 electrical engineering, electronic engineering, information engineering ,[INFO]Computer Science [cs] ,wireless sensor networks ,environmental risk monitoring ,[ INFO.INFO-DS ] Computer Science [cs]/Data Structures and Algorithms [cs.DS] ,scalable sensor node placement algorithm ,010401 analytical chemistry ,stochastic physics-based optimisation algorithm ,fixed target coverage applications ,020206 networking & telecommunications ,0104 chemical sciences ,Key distribution in wireless sensor networks ,virtual sensors ,Software deployment ,Sensor node ,Simulated annealing ,Scalability ,simulated annealing ,Wireless sensor network ,Algorithm - Abstract
International audience; Large applications of sensor networks, such as environmental risk monitoring, require the deployment of hundreds or even thousands of nodes. This study proposes and implements a novel stochastic physics-based optimisation algorithm that is both efficient (guarantees full target coverage with a reduced number of sensors) and scalable (meaning that it can be executed for very large-scale problems in a reasonable computation time). The algorithm employs ‘virtual sensors’ which move, merge, recombine, and ‘explode’ during the course of the algorithm, where the process of merging and recombining virtual sensors reduces the number of actual sensors while maintaining full coverage. The parameters which control sensor merging and explosion are varied during the algorithm to perform the same function as an annealing schedule in simulated annealing. Simulation results illustrate the rapidity and the effectiveness of the proposed method. more...
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- 2017
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35. Analog circuit design and optimal synchronization of a modified Rayleigh system
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Samuel Bowong, Saïdou, Michaux Kountchou, Hilaire Bertrand Fotsin, Patrick Louodop, University of Dschang, Institute of Geological and Mining Research, University of Douala, UMI 209 IRD&UPMC UMMISCO, Project Team GRIMCAPE, University of Yaounde 1, University of Yaounde I, and Universidade Estadual Paulista (Unesp) more...
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Engineering ,Chaotic ,Aerospace Engineering ,Controllability function ,Ocean Engineering ,01 natural sciences ,System model ,symbols.namesake ,Control theory ,0103 physical sciences ,Synchronization (computer science) ,Chaos synchronization ,Electrical and Electronic Engineering ,Rayleigh scattering ,010306 general physics ,010301 acoustics ,Electronic circuit ,Pspice analog circuit implementation ,Optimal feedback control ,business.industry ,Applied Mathematics ,Mechanical Engineering ,Controllability ,Modified Rayleigh system ,Control and Systems Engineering ,symbols ,business ,Energy (signal processing) - Abstract
Made available in DSpace on 2018-12-11T17:01:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-07-01 This paper addresses the problem of optimization of the synchronization of a chaotic modified Rayleigh system. We first introduce a four-dimensional autonomous chaotic system which is obtained by the modification of a two-dimensional Rayleigh system. Some basic dynamical properties and behaviors of this system are investigated. An appropriate electronic circuit (analog simulator) is proposed for the investigation of the dynamical behavior of the proposed system. Correspondences are established between the coefficients of the system model and the components of the electronic circuit. Furthermore, we propose an optimal robust adaptive feedback which accomplishes the synchronization of two modified Rayleigh systems using the controllability functions method. The advantage of the proposed scheme is that it takes into account the energy wasted by feedback coupling and the closed loop performance on synchronization. Also, a finite horizon is explicitly computed such that the chaos synchronization is achieved at an established time. Numerical simulations are presented to verify the effectiveness of the proposed synchronization strategy. Pspice analog circuit implementation of the complete master–slave controller system is also presented to show the feasibility of the proposed scheme. Laboratory of Electronics and Signals Processing Department of Physics Faculty of Science University of Dschang, P.O. Box 67 Nuclear Technology Section Institute of Geological and Mining Research, P.O. Box 4110 Laboratory of Applied Mathematics Department of Mathematics and Computer Science Faculty of Science University of Douala, P.O. Box 24157 UMI 209 IRD&UPMC UMMISCO LIRIMA Project Team GRIMCAPE The African Center of Excellence in Information and Communication Technologies (CETIC) University of Yaounde 1 Nuclear Physics Laboratory Faculty of Science University of Yaounde I, P.O. Box 812 Instituto de Física Teórica UNESP Universidade Estadual Paulista, Rua Dr. Bento Teobaldo Ferraz 271, Bloco II, Barra Funda Instituto de Física Teórica UNESP Universidade Estadual Paulista, Rua Dr. Bento Teobaldo Ferraz 271, Bloco II, Barra Funda more...
- Published
- 2016
36. Association of serum leptin and adiponectin with anthropomorphic indices of obesity, blood lipids and insulin resistance in a Sub-Saharan African population
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Clarisse Noël Ayina Ayina, Michel K. Mengnjo, Jean François Gautier, Jean Claude Mbanya, Jean Jacques Noubiap, Laurent Serge Etoundi Ngoa, Eugene Sobngwi, Philippe Boudou, Dpt of Animal Science [Douala], Université de Douala, Groote Schuur and Red Cross Children's Hospital, University of Cape Town, Medical diagnostic center, Yaoundé, Department of Animal Science [Yaoudé], National Advanced School of Engineering (University of Yaounde I), Service de Biologie Hormonale [CHU Saint-Louis], Groupe Hospitalier Saint Louis - Lariboisière - Fernand Widal [Paris], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Centre de Recherche des Cordeliers (CRC), Université Pierre et Marie Curie - Paris 6 (UPMC)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de diabétologie et d'endocrinologie [CHU Lariboisière], Hôpital Lariboisière-Fernand-Widal [APHP], University of Yaoundé [Cameroun], National Obesity Center [Yaoundé], Hôpital Central de Yaoundé [Yaoundé], Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE), Department of Medicine, Faculty of Health Sciences, National Advanced School of Engineering ( University of Yaounde I ), Centre de Recherche des Cordeliers ( CRC ), Université Paris Diderot - Paris 7 ( UPD7 ) -École pratique des hautes études ( EPHE ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Université Paris Descartes - Paris 5 ( UPD5 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ), Hôpital Lariboisière, and HAL-UPMC, Gestionnaire more...
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0301 basic medicine ,Male ,Serum ,Blood Glucose ,Leptin ,Endocrinology, Diabetes and Metabolism ,Fat Body ,Clinical Biochemistry ,Blood lipids ,Blood Pressure ,Body Mass Index ,Plasma ,0302 clinical medicine ,Waist–hip ratio ,Endocrinology ,Prevalence ,Medicine ,Insulin ,Homeostasis ,Cameroon ,Adiposity ,2. Zero hunger ,education.field_of_study ,[SDV.MHEP] Life Sciences [q-bio]/Human health and pathology ,Fasting ,Middle Aged ,Insulin sensitivity ,Lipids ,3. Good health ,Blood ,Cholesterol ,Obesity, Abdominal ,Regression Analysis ,Female ,Adiponectin ,Waist Circumference ,medicine.medical_specialty ,Population ,Adipokine ,030209 endocrinology & metabolism ,Medical Biochemistry ,03 medical and health sciences ,Insulin resistance ,Adipokines ,Internal medicine ,[ SDV.MHEP ] Life Sciences [q-bio]/Human health and pathology ,Humans ,Obesity ,education ,Triglycerides ,Lipidology ,Biochemistry, medical ,Homo sapiens ,business.industry ,Waist-Hip Ratio ,Research ,Biochemistry (medical) ,nutritional and metabolic diseases ,Cholesterol, LDL ,medicine.disease ,030104 developmental biology ,Cross-Sectional Studies ,business ,[SDV.MHEP]Life Sciences [q-bio]/Human health and pathology ,Obesity indices - Abstract
International audience; BackgroundThere is little data on the metabolic effects of adipokines in sub-Saharan African populations. This study aimed to explore the potential relationship of leptin and adiponectin, with obesity, plasma lipids and insulin resistance in a Cameroonian population.MethodsWe enrolled 167 men and 309 women aged ≥18 years from the general population in Cameroon. Data were collected on waist circumference (WC), body mass index (BMI), waist-to-hip ratio (WHR), body fat (BF%), fasting blood glucose, plasma lipids, adiponectin, leptin, insulin and homeostasis model for assessment of insulin resistance (HOMA-IR). Pearson’s correlation and multiple stepwise linear regression analyses were used to determine correlates of leptin and adiponectin serum levels.ResultsThe prevalence of obesity was higher in women compared to men (p more...
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- 2016
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37. Amino acids, major carotenoids and vitamin A activity of some traditional sauces consumed in the Far North Region of Cameroon
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Joëlle Léonil, Frédéric Gaucheron, Elie Fokou, Michel Piot, Roger Ponka, Germain Kansci, Eric Beaucher, Science et Technologie du Lait et de l'Oeuf (STLO), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Department of Agriculture, Livestock and By-Products, The Higher Institute of the Sahel, University of Maroua (UMa), Department of Biochemistry, Faculty of Science, University of Yaounde, University of Yaounde ́, (French Cooperation, N̊ bourses /331/06/2012), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), and University of Yaoundé [Cameroun] more...
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2. Zero hunger ,chemistry.chemical_classification ,Vitamin ,Methionine ,Retinol ,afrique ,Phenylalanine ,Amino acid ,sauce ,chemistry.chemical_compound ,acide aminé ,chemistry ,Biochemistry ,cameroun ,caroténoide ,[SDV.IDA]Life Sciences [q-bio]/Food engineering ,vitamine A ,composition des aliments ,Leucine ,Carotenoid ,[SDV.AEN]Life Sciences [q-bio]/Food and Nutrition ,Food Science ,Cysteine - Abstract
The aim of this study was to determine the amino acids major carotenoids and vitamin A activity in the 22 most frequently consumed traditional sauces in the Far North Region of Cameroon. Results showed that the most abundant amino acids in all sauces were glumatic acid (119–192 mg/g protein), aspartic acid (61.3–132 mg/g protein), leucine (34.5–99.2 mg/g protein) and phenylalanine (22.1–64.3 mg/g protein). High levels of amino acids were found in Gouboudou. Essential amino acids in most of the sauces represented up to 33% of total amino acids, indicating a good equilibrium between amino acids. Essential amino acids in most of these sauces met the recommended children requirement of the FAO/WHO/UNU for children 1–2 years old, except methionine and cysteine. Methionine + cysteine and lysine were the limiting amino acids in these sauces. Carotenoids and vitamin A activity (0.02–0.15 mg retinol activity equivalents/100 g dry weight) were present only in small quantities in all sauces when compared with other African sauces. more...
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- 2015
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38. Tidal effect on the dispersion of fecal pollution indicator bacteria and associated health risks along the Kribi beaches (Southern Atlantic coast, Cameroon)
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Paul Alain Nana, Rodrigue Ebonji Seth, Noël Arlette Ndjuissi Tamko, Victorin Rodrigue Onambélé Ossomba, Geneviève Bricheux, Claire Stéphane Metsopkeng, Moïse Nola, Télesphore Sime-Ngando, Department of Oceanography and Limnology, Institute of Fisheries and Aquatic Sciences, University of Douala, Douala, Cameroon, Institute of Fisheries and Aquatic Sciences (ISH) at Yabassi, University of Douala, PO Box 2701, Douala, Cameroon, Laboratory of Aquaculture and Demography of Aquatic Resources, Institute of Fisheries and Aquatic Sciences, Department of Aquaculture, University of Douala, P.O. Box 7236 Douala-Cameroon, Department of Oceanography, Institute of Fisheries and Aquatic Sciences, University of Douala, Douala, Cameroon, Laboratoire Microorganismes : Génome et Environnement (LMGE), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Université d'Auvergne - Clermont-Ferrand I (UdA)-Centre National de la Recherche Scientifique (CNRS), Hydrobiology and Environment Laboratory, University of Yaounde 1, Faculty of Sciences, P.O. Box 812 Yaounde, Cameroon, and Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA) more...
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Ecology ,Animal Science and Zoology ,Aquatic Science ,Fecal pollution Health risks Kribi beaches Tidal cycles Solid and liquid waste management ,[SDV.MP.PRO]Life Sciences [q-bio]/Microbiology and Parasitology/Protistology ,[SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology ,Ecology, Evolution, Behavior and Systematics - Abstract
International audience; Assessment of fecal contamination indicator bacteria concentrations on beaches are important for health risk prevention and management. This study assessed temporal changes in bacterial abundances as a function of tidal cycles and seasons along the Kribi beaches, Cameroon. Overall, samples taken during low and high tides during the different seasons of the year showed that the waters of Kribi beaches are exposed to fecal contamination due to the presence of different concentrations of fecal coliforms (5-35 CFU/100 ml), total coliforms (100-600 CFU/100 ml), Escherichia coli (0-15 CFU/100 ml), Streptococcus feacalis (50-700 CFU/100 ml), Pseudomonas aeruginosa (300-7200 CFU/100 ml), Vibrio cholerea (5-250 CFU/100 ml), Vibrio parahemoliticus (0-115 CFU/100 ml), and Aerobic Mesophilic Heterotrophic Bacteria (99-875 CFU/100 ml). Regardless of bacterial strain and sampling site, cell abundances were significant at low tides and during rainy seasons. At each sampling station (Mpalla, Ngoyè and Mboamanga), depending on the seasons and tidal cycles, significant correlations were recorded between the abundances of some bacterial strains and some environmental variables (P < 0.05). The presence and high abundance of these potentially pathogenic bacterial strains in the waters of Kribi beaches constitute a real public health threat for swimmers. The limitation of this microbiological pollution requires the implementation of an efficient collection and treatment plan for solid and liquid waste (sanitary wastewater) in the city of Kribi. more...
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- 2023
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39. The one step fixed-lag particle smoother as a strategy to improve the prediction step of particle filtering
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Nyobe, Samuel, Campillo, Fabien F., Moto, Serge, Rossi, Vivien, University of Yaoundé [Cameroun], Unité de modélisation mathématique et informatique des systèmes complexes [Bondy] (UMMISCO), Université de Yaoundé I-Institut de la francophonie pour l'informatique-Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD)-Université Gaston Bergé (Saint-Louis, Sénégal)-Université Cadi Ayyad [Marrakech] (UCA)-Sorbonne Université (SU)-Institut de Recherche pour le Développement (IRD [France-Nord]), Mathématiques pour les Neurosciences (MATHNEURO), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Forêts et Sociétés (UPR Forêts et Sociétés), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), University of Yaounde I, National Advanced School of Engineering, Department of Mathematic and Physical Science, and Campillo, Fabien more...
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FOS: Computer and information sciences ,particle filter ,[STAT.AP]Statistics [stat]/Applications [stat.AP] ,[STAT.AP] Statistics [stat]/Applications [stat.AP] ,extended Kalman filter ,prediction step ,Applications (stat.AP) ,bootstrap particle filter ,one step fixed-lag particle smoother ,unscented Kalman filter ,Statistics - Applications - Abstract
Sequential Monte Carlo methods have been a major breakthrough in the field of numerical signal processing for stochastic dynamical state-space systems with partial and noisy observations. However, these methods still present certain weaknesses. One of the most fundamental is the degeneracy of the filter due to the impoverishment of the particles: the prediction step allows the particles to explore the state-space and can lead to the impoverishment of the particles if this exploration is poorly conducted or when it conflicts with the following observation that will be used in the evaluation of the likelihood of each particle. In this article, in order to improve this last step within the framework of the classic bootstrap particle filter, we propose a simple approximation of the one step fixed- lag smoother. At each time iteration, we propose to perform additional simulations during the prediction step in order to improve the likelihood of the selected particles.; Les méthodes de Monte Carlo séquentielles ont constitué une percée majeure dans le domaine du traitement numérique du signal pour les systèmes dynamiques stochastiques à espace d'état avec observations partielles et bruitées. Cependant, ces méthodes présentent encore certaines faiblesses. L'une des plus fondamentales est la dégénérescence du filtre due à l'appauvrissement des particules : l'étape de prédiction permet aux particules d'explorer l'espace d'état et peut conduire à l'appauvrissement des particules si cette exploration est mal menée ou lorsqu'elle entre en conflit avec l'observation suivante qui sera utilisée dans l'évaluation de la vraisemblance de chaque particule. Dans cet article, afin d'améliorer cette dernière étape dans le cadre du filtre particulaire bootstrap classique, nous proposons une approximation simple du lisseur à retard fixe à un pas. A chaque itération temporelle, nous proposons d'effectuer des simulations supplémentaires pendant l'étape de prédiction afin d'améliorer la vraisemblance des particules sélectionnées. more...
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- 2023
40. Microstructure and physico-chemical transformation of some common woods from Cameroon during drying
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Sylvie Rossignol, Epiphanie Nouemsi Soubgui, Cristina Leonelli, Elie Kamseu, René Oum Lissouck, Rufin Theophile Tene Fongang, Likiby Boubakar, Fernanda Andreola, MINRESI/MIPROMALO, National Advanced School of Engineering (University of Yaounde I), University of Modena and Reggio Emilia, IRCER - Axe 3 : organisation structurale multiéchelle des matériaux (IRCER-AXE3), Institut de Recherche sur les CERamiques (IRCER), Institut de Chimie du CNRS (INC)-Institut des Procédés Appliqués aux Matériaux (IPAM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut des Procédés Appliqués aux Matériaux (IPAM), and Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS) more...
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040101 forestry ,Thermogravimetric analysis ,Materials science ,Macropore ,[CHIM.MATE]Chemical Sciences/Material chemistry ,04 agricultural and veterinary sciences ,02 engineering and technology ,15. Life on land ,Wood drying ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Microstructure ,[SPI.MAT]Engineering Sciences [physics]/Materials ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Decomposition process ,Density ,Porosity ,Wood ,0401 agriculture, forestry, and fisheries ,Lignin ,Hemicellulose ,Physical and Theoretical Chemistry ,Cellulose ,0210 nano-technology ,ComputingMilieux_MISCELLANEOUS - Abstract
The influence of drying on the microstructure, physical and chemical properties of some tropical wood species has been investigated using thermogravimetric analysis, differential scanning calorimetric (DSC), FTIR-ATR spectroscopy, mercury intrusion porosimetry (MIP) and environmental scanning electron microscopy (ESEM) analysis. Eleven tropical species were used in this study. Results showed that the common Cameroonian wood species can be grouped into three classes: Ga (lightwood) with cross-linking fibers having high volume of macropores, density in the range 0.2–0.4 g cm−3 and high lignin content; Gb (medium dense) with unidirectional fibers packing, density around 0.6 g cm−3 and Gc group showing high densification of unidirectional fibers and low porosity justifying the density > 0.8 g cm−3. Both the Gb an Gc groups have less significant lignin content. A relatively high rate of drying for Ga with respect to low drying rate for Gc was observed in direct relation with their porosity of ~ 72 Vol% and ~ 36 Vol%, respectively. LTF and WG showed similar cumulative pore volume (0.44 mL g−1) with different pore size distribution: 28% and 22% of macropores, 39% and 60% of mesopores and 33% and 18% micropores, respectively. Thermal analysis revealed that lightwoods have the highest amounts of residues and lower thermal stability of chemical components than dense woods. It has been found that the degradation process of hemicellulose, cellulose and lignin occurs mainly at about 200–300 °C, 300–350 °C and 350–500 °C, respectively. The group Ga with low drying rate, a low cycle of reproduction, a high volume of porosity together with large pore sizes appeared promising candidates for the design of ecological, environmental and sustainable management policy of wood transformation in developing countries and even worldwide. more...
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- 2020
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41. The path to shared prosperity: Leveraging financial services outreach to create decent jobs in developing countries
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Aïssata Coulibaly, Urbain Thierry Yogo, Centre d'Études et de Recherches sur le Développement International (CERDI), Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), CEREG - University of Yaounde 2, ANR-10-LABX-0014,IDGM+,Designing new international development policies from research outcomes. An enhanced(2010), and ANR-10-LABX-0014,IDGM+,Designing new international development policies from research outcomes. An enhanced 'Initiative for Development and Global Governance'(2010) more...
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Economics and Econometrics ,Private credit ,media_common.quotation_subject ,JEL: J - Labor and Demographic Economics/J.J8 - Labor Standards: National and International/J.J8.J80 - General ,Developing country ,Developing countries ,JEL: G - Financial Economics/G.G2 - Financial Institutions and Services/G.G2.G21 - Banks • Depository Institutions • Micro Finance Institutions • Mortgages ,0502 economics and business ,Development economics ,JEL: I - Health, Education, and Welfare/I.I3 - Welfare, Well-Being, and Poverty/I.I3.I30 - General ,Economics ,Bank penetration ,Trickle-down hypothesis ,Asset (economics) ,050207 economics ,10. No inequality ,Financial services ,media_common ,Decent job ,Financial outreach ,Financial inclusion ,[SHS.STAT]Humanities and Social Sciences/Methods and statistics ,050208 finance ,Poverty ,business.industry ,05 social sciences ,1. No poverty ,JEL: O - Economic Development, Innovation, Technological Change, and Growth/O.O1 - Economic Development/O.O1.O16 - Financial Markets • Saving and Capital Investment • Corporate Finance and Governance ,JEL: O - Economic Development, Innovation, Technological Change, and Growth/O.O1 - Economic Development/O.O1.O15 - Human Resources • Human Development • Income Distribution • Migration ,[SHS.ECO]Humanities and Social Sciences/Economics and Finance ,Investment (macroeconomics) ,JEL: D - Microeconomics/D.D3 - Distribution/D.D3.D31 - Personal Income, Wealth, and Their Distributions ,Working poverty ,Outreach ,Remittances ,[SHS.ENVIR]Humanities and Social Sciences/Environmental studies ,8. Economic growth ,Prosperity ,business - Abstract
International audience; Understanding the channels through which financial inclusion affects poverty reduction remains a key policy issue in development debates. Considering that labour is the main asset of the poor, this paper investigates the effect of financial outreach on the number of workers living below the poverty line. It also analyses whether this effect may occur through increasing investment, remittances, private credit and the number of rich workers who can provide employment opportunities to the poorest. The study finds that improving financial outreach through additional bank branches reduces the number of poor workers, especially in developing countries hit by macro economic instability. In addition, this effect occurs mainly through credit expansion, while other channels substitute financial outreach in countries with a low level of financial development. more...
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- 2020
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42. Spatio-temporal modelling of tree-grass dynamics in humid savannas: Interplay between nonlocal competition and nonlocal facilitation
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S.R. Tega, I.V. Yatat-Djeumen, J.J. Tewa, P. Couteron, Unité de modélisation mathématique et informatique des systèmes complexes [Bondy] (UMMISCO), Institut de Recherche pour le Développement (IRD [France-Nord])-Institut de la francophonie pour l'informatique-Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD)-Université Gaston Bergé (Saint-Louis, Sénégal)-Université Cadi Ayyad [Marrakech] (UCA)-Université de Yaoundé I-Sorbonne Université (SU), National Advanced School of Engineering (University of Yaounde I), Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) more...
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0106 biological sciences ,Competition ,010604 marine biology & hydrobiology ,Applied Mathematics ,Grass ,Vegetation patterns ,15. Life on land ,[SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics ,[SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy ,010603 evolutionary biology ,01 natural sciences ,[SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems ,Reaction-diffusion equations ,13. Climate action ,Nonlocal interaction ,Modeling and Simulation ,Facilitation ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,Tree - Abstract
International audience; For about twenty years, the question about the essential factors promoting the long-lasting coexistence of trees and grasses in humid savannas is at the center of several mathematical works, by the construction of deterministic and/or stochastic mathematical models. A closely related topic is coexistence of open savanna and forest patches at landscape scales, which raises the challenge of accounting for contrasted spatial patterns under similar climate conditions through fire mediated tree-grass interaction models. In this work, we propose and study a deterministic spatio-temporal fire-mediated tree-grass interactions model. The model is based on two nonlocal reaction-diffusion equations with kernels of intra and inter-specific interactions, corresponding to woody and grassy biomasses. A novelty in this paper is the consideration of a kernel-based nonlocal facilitation of trees by other trees to promote growth of seedlings/shrubs and, indirectly, limit fire propagation and its impact. We also take into account a kernel-based nonlocal competition of trees on grasses for light availability and nutrients. A qualitative analysis of the model is carried out and it reveals several ecological thresholds that shape the overall dynamics of the system. Depending on these thresholds, monostability of the forest, grassland or savanna space-homogeneous stationary state and multistabilities (i.e. involving more that one space-homogeneous stationary state) are proven possible. Thanks to the nonlocal biomasses interactions, our model accounts for the occurrence of space inhomogeneous solutions, including a possibly periodic spatial structuring sometimes observed in the humid savanna zone. Specifically, linear stability analyses, performed in the vicinity of space-homogeneous stationary states, provides conditions for the appearance of space inhomogeneous solutions including spatially periodic or aperiodic ones. Finally, numerical simulations are presented to illustrate our theoretical results. Notably, we verify that the computed spatial wavelengths were in good agreement with the predictions from the theoretical analysis. more...
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- 2022
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43. Integrated Approach to Eco-Friendly Thermoplastic Composites Based on Chemically Recycled PET Co-Polymers Reinforced with Treated Banana Fibres
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Martial Aime Kuete, Pascal Van Velthem, Wael Ballout, Bernard Nysten, Jacques Devaux, Maurice Kor Ndikontar, Thomas Pardoen, Christian Bailly, UCL - SST/IMCN/BSMA - Bio and soft matter, University of Yaounde - Macromolecular Chemistry Unit, and UCL - SST/IMMC/IMAP - Materials and process engineering more...
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PET ,Polymers and Plastics ,Solid-state polymerisation ,Recycling ,General Chemistry ,composite ,recycling ,glycolysis ,solid-state polymerisation ,sustainability ,Glycolysis - Abstract
A major societal issue of disposal and environmental pollution is raised by the enormous and fast-growing production of single-use polyethylene terephthalate (PET) bottles, especially in developing countries. To contribute to the problem solution, an original route to recycle PET in the form of value-added environmentally friendly thermoplastic composites with banana fibres (Musa acuminata) has been developed at the laboratory scale. Banana fibres are a so far undervalued by-product of banana crops with great potential as polymer reinforcement. The melt-processing constraints of commercial PET, including used bottles, being incompatible with the thermal stability limits use of natural fibres; PET has been modified with bio-sourced reactants to produce co-polymers with moderate processing temperatures below 200 °C. First, commercial PET were partially glycolyzed with 1.3-propanediol to produce co-oligomers of about 20 repeating units, which were next chain extended with succinic anhydride and post-treated in a very unusual “soft solid state” process at temperatures in the vicinity of the melting point to generate co-polymers with excellent ductility. The molar mass build-up reaction is dominated by esterification of the chain ends and benefits from the addition of succinic anhydride to rebalance the acid-to-hydroxyl end-group ratio. Infra-red spectroscopy and intrinsic viscosity were extensively used to quantify the concentration of chain ends and the average molar mass of the co-polymers at all stages of the process. The best co-polymers are crystallisable, though at slow kinetics, with a Tg of 48 °C and a melting point strongly dependent upon thermal history. The composites show high stiffness (4.8 GPa at 20% fibres), consistent with the excellent dispersion of the fibres and a very high interfacial cohesion. The strong adhesion can be tentatively explained by covalent bonding involving unreacted succinic anhydride in excess during solid stating. A first approach to quantify the sustainable benefits of this PET recycling route, based on a rational eco-selection method, gives promising results since the composites come close to low-end wood materials in terms of the stiffness/embodied energy balance. Moreover, this approach can easily be extended to many other natural fibres. The present study is limited to a proof of concept at the laboratory scale but is encouraging enough to warrant a follow-up study toward scale-up and application development. more...
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- 2022
44. Comparative Approach of the Antibiotics Susceptibility of some Bacterial Strains Concurrently Isolated from Raw Milk and Cattle Feed (Water and Fodder) from some Farms in the West Region of Cameroon (Central Africa)
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M. Nola, T. Sime-Ngando, E. Masseret, P. A. Nana, L. M. Moungang, O. V. Noah Ewoti, H. Bayemi Pougue, S. Lacmata Tamekou, Y. Poutoum Yogne, A. Manouore Njoya, A. Tamsa Arfao, J. S. Eheth, C. S. Metsopkeng, P. Ngo Bahebeck, Laboratory of Hydrobiology and Environment, Faculty of Science, University of Yaounde 1, P.O. BOX 812, Yaounde, Cameroon, Institut de Recherche Agricole pour le Développement [Yaoundé] (IRAD), Research Unit of Microbiology and Antimicrobial Substances, Faculty of Sciences, University of Dschang (rumas), Department of Oceanography and Limnology, Institute of Fisheries and Aquatic Sciences, University of Douala, Douala, Cameroon, MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Laboratoire Microorganismes : Génome et Environnement (LMGE), and Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA) more...
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green fodder ,raw milk ,drinking water ,[SDE]Environmental Sciences ,Escherichia coli ,General Medicine ,antibiotic susceptibility ,Salmonella spp ,Brucella spp - Abstract
Introduction: Foodborne resistant bacteria have become a challenge to food security. Milk and milk products are easy vectors of transmission of foodborne pathogens, these being the main sources of human infection by antimicrobial resistant pathogens. The present study aimed at making a comparative approach of the antibiotic sensitivity/resistance of 3 bacterial strains (Escherichia coli, Salmonella spp. and Brucella spp.) isolated from milk, drinking water and green fodder consumed by cows in the West Cameroon region (Central Africa). Methodology: A total of 48 raw milk samples, 48 water samples and 48 green fodder samples were collected during the year 2020 and subjected to culture and identification of Escherichia coli, Salmonella spp. and Brucella spp. Antibiotic susceptibility testing was performed using the antibiotic disc diffusion method. Results: Escherichia coli isolates showed high resistance (56-100%) to ampicillin, amoxicillin/clavulanic acid, cefotaxime, ceftazidime and ceftriaxone in all three samples. Salmonella spp. isolates showed resistance to ampicillin only (62, 67 and 67%). Brucella spp. strains isolated from raw milk and drinking water showed high sensitivity (78-100%) to azithromycin, doxycycline, ciprofloxacin, levofloxacin, gentamicin, rifampicin and trimethoprim/sulfamethoxazole, streptomycin and tetracycline. Antibiotic sensitivity/resistance to Escherichia coli and Salmonella spp. strains largely did not differ between samples (P>0.05). No difference in sensitivity/resistance (P>0.05) of Brucella spp. strains isolated from milk and water was observed with respect to the 10 antibiotics tested. Conclusions: The emergence of resistance to various antibiotics commonly used in medical and veterinary practices has important implications for public health. It seems necessary to strengthen of the regulations covering the sale and prescription of antibiotics. more...
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- 2021
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45. Bianchi type-I magnetized cosmological models for the Einstein-Boltzmann equation with the cosmological constant
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Noutchegueme, Norbert [Department of Mathematics, Faculty of Science, University of Yaounde I, P.O. Box 812, Yaounde (Cameroon)]
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- 2015
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46. Mathematical modelling of Banana Black Sigatoka Disease with delay and Seasonality
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Franklin Agouanet, Jean Jules Tewa, Israël Tankam-Chedjou, Remy Magloire Etoua, Département de Mathématiques Université de Yaoundé 1 = Department of Mathematics [Yaoundé, Cameroon], Université de Yaoundé I, Laboratoire International de Recherche en Informatique et Mathématiques Appliquées (LIRIMA), Université de Yaoundé I-Université Badji Mokhtar - Annaba [Annaba] (UBMA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Joseph Ki-Zerbo [Ouagadougou] (UJZK)-Université d'Antananarivo-Université Gaston Bergé Sénégal-Centre National de la Recherche Scientifique et Technologique (CNRST), National Advanced School of Engineering (University of Yaounde I), Centre d’Excellence en Technologies de l’Information et de la Communication (CETIC asbl), Unité de modélisation mathématique et informatique des systèmes complexes [Bondy] (UMMISCO), Institut de Recherche pour le Développement (IRD [France-Nord])-Institut de la francophonie pour l'informatique-Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD)-Université Gaston Bergé (Saint-Louis, Sénégal)-Université Cadi Ayyad [Marrakech] (UCA)-Université de Yaoundé I-Sorbonne Université (SU), EPITAG, Université de Yaoundé I-Université Badji Mokhtar Annaba (UBMA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Joseph Ki-Zerbo [Ouagadougou] (UJZK)-Université d'Antananarivo-Université Gaston Bergé Sénégal-Centre National de la Recherche Scientifique et Technologique (CNRST), Université de Yaoundé I-Institut de la francophonie pour l'informatique-Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD)-Université Gaston Bergé (Saint-Louis, Sénégal)-Université Cadi Ayyad [Marrakech] (UCA)-Sorbonne Université (SU)-Institut de Recherche pour le Développement (IRD [France-Nord]), Department of Mathematics [Yaoundé], and University of Yaoundé [Cameroun] more...
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0106 biological sciences ,0303 health sciences ,Black sigatoka ,biology ,Applied Mathematics ,[MATH.MATH-DS]Mathematics [math]/Dynamical Systems [math.DS] ,[SDV.SA.AGRO]Life Sciences [q-bio]/Agricultural sciences/Agronomy ,food and beverages ,Seasonality ,biology.organism_classification ,medicine.disease ,01 natural sciences ,[INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation ,03 medical and health sciences ,Modeling and Simulation ,Statistics ,medicine ,Mycosphaerella ,Basic reproduction number ,ComputingMilieux_MISCELLANEOUS ,030304 developmental biology ,010606 plant biology & botany ,Mathematics - Abstract
Black Sigatoka Disease, also called Black Leaf Streak Disease (BLSD), is caused by the fungus Mycosphaerella fijiensis and is arguably one of the most important pathogens affecting the banana and plantain industries. Theoretical results on its dynamics are rare, even though theoretical descriptions of epidemics of plant diseases are valuable steps toward their efficient management. In this paper, we propose a mathematical model describing the dynamics of BLSD on banana or plantain leaves within a whole field of plants. The model consists of a system of periodic non-autonomous differential equations with a time delay that accounts for the time of incubation ofM. fijiensis’ spores. We compute the basic reproduction number of the disease and show that it does not depend on the time delay, meaning that the persistence of BLSD would not qualitatively change even if the incubation period of the pathogen is perturbed. We derive local and global long-term dynamics of the disease and provide numerical simulations to illustrate our results. more...
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- 2021
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47. MINIMUM INHIBITION AND BACTERICIDAL CONCENTRATIONS OF THE PLANT MORINGA OLEIFERA EXTRACTS AGAINST THE BACTERIA ESCHERICHIA COLI AND STAPHYLOCOCCUS AUREUS
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Claire Stéphane Metsopkeng, Mireille Ebiane Nougang, Antoine Tamsa Arfao, Fanny Perrière, Luciane Marlyse Moungang, Olive Vivien Noah Ewoti, Florence Donnadieu, Paul Alain Nana, Geneviève Bricheux, Jean Samuel Eheth, Edith Brunelle Mouafo Tamnou, Isabelle Ripoche, Pierre Chalard, Télesphore Sime-Ngando, Moïse Nola, Laboratory of Zoology, Faculty of Science, University of Yaoundé I, P.O. Box 812 Yaoundé, Cameroon, Université de Yaoundé I, Zoology laboratory ( Faculty of Sciences), Laboratoire Microorganismes : Génome et Environnement (LMGE), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Microbiology Laboratory, University of Yaounde 1, Faculty of Sciences, Department of Oceanography, Institute of Fisheries and Aquatic Sciences, University of Douala, Douala, Cameroon, Laboratoire de Modélisation et Sûreté des Systèmes - LM2S (LM2S), Institut de Chimie de Clermont-Ferrand (ICCF), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Institut national polytechnique Clermont Auvergne (INP Clermont Auvergne), Université Clermont Auvergne (UCA)-Université Clermont Auvergne (UCA), University of Yaoundé [Cameroun], Laboratory of Hydrobiology and Environment, Faculty of Science, University of Yaoundé I, P.O. BOX 812, Yaoundé, Cameroon., and Faculté des Sciences - Yaoundé I more...
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Polymers and Plastics ,[SDE]Environmental Sciences ,[CHIM]Chemical Sciences ,[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie ,[SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology ,General Environmental Science - Abstract
International audience; This study aimed at assessing the MICs (Minimum Inhibitory Concentrations) and the MBCs (Minimum Bactericidal Concentrations) of the methanolic extracts from 4 different parts (leaves, seeds, stem, roots) of the plant Moringa oleifera against the bacteria E. coli and S. aureus. Phytochemical profile of each extract has been determined using LC/MS analyses. Microbial analyses were done using 96-wells plate method. Results showed that the four parts on the plants contain heterosides and glucosinolates. Iridoids were found in leaves, stem and roots. Flavonoids were found in leaves and stem. Phenolic acids were found only in leaves and carboxylic acids found only in stem. The abundance and the number of identified compounds of a given class varied from one part of plant to another. The MICs and MBCs varied with respect to the microorganism and the part of the plant. With E. coli, the MICs varied from 0.009 (leaves) to 1.25 mg/mL (seeds), and the MBCs varied from 0.156 (leaves) to 2.5 mg/mL (seeds and stem). With S. aureus, the MICs varied from 0.009 (stem and roots) to 0.039 mg/mL (leaves and roots), and the MBCs varied from 0.078 (leaves) to 4 mg/mL (stem). The bactericidal or bacteriostatic properties of the extracts varied depending on the part of the plant and the microorganism considered. Against E. coli, the leaves, stem and roots extracts were bacteriostatic whereas seeds extract was bactericidal. Against S. aureus, the seeds, stem and roots extracts were bacteriostatic whereas leaves extract was bactericidal. more...
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- 2021
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48. Biocontrol of the Brown Cocoa Mirids Using Neem Oil and an Ethanolic Extract from Neem under Laboratory Conditions
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S. Eteme Enama, Raymond Joseph Mahob, Christian Cilas, C.F. Bilong Bilong, D. M. Taliedje, I. Mama Ngah, Hermine Claudine Mahot, Y.G. Fotso Toguem, Rachid Hanna, University of Yaoundé [Cameroun], Laboratory of Parasitology and Ecology, Faculty of Science, University of Yaoundé I, P.O. Box 812 Yaoundé, Cameroon, Université de Yaoundé I, Institute of Agricultural Research for Development (IRAD), Institut de Recherche Agricole pour le Développement [Yaoundé] (IRAD), International Institute of Tropical Agriculture (IITA-Cameroon), International Institute of Tropical Agriculture [Nigeria] (IITA), Consultative Group on International Agricultural Research [CGIAR] (CGIAR)-Consultative Group on International Agricultural Research [CGIAR] (CGIAR), Agrosystèmes Biodiversifiés (UMR ABSys), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Direction Générale Déléguée à la Recherche et à la Stratégie (Cirad-Dgdrs), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), and This study was funded by the special research allowances from the Ministry of Higher Education and internal allowances from the University of Yaounde I. Thanks to the Institute of Agricultural Research for Development and the International Institute of Tropical Agriculture for logistic and laboratory products. more...
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0106 biological sciences ,Insecticide d'origine végétale ,insecticide biologique ,[SDV]Life Sciences [q-bio] ,Sahlbergella singularis ,Biological pest control ,H02 - Pesticides ,Gestion intégrée des ravageurs ,Biology ,01 natural sciences ,Toxicology ,Ingestion ,Theobroma cacao ,Huile de neem ,Ecology, Evolution, Behavior and Systematics ,Neem oil ,Azadirachta indica ,High mortality ,cocoa agroforestry systems ,Pesticide ,H10 - Ravageurs des plantes ,biopesticide ,integrated pest management (IPM) ,010602 entomology ,Biopesticide ,Insect Science ,PEST analysis ,Lutte biologique contre les ravageurs ,Agronomy and Crop Science ,Insecte nuisible ,010606 plant biology & botany - Abstract
International audience; The African mirid bug (Sahlbergella singularis) is the most economically important insect pest in cocoa farms. Pesticide management, although controversial due to the adverse effects of these substances on the environment and on human health, remains the main option used for controlling this pest. In the recent decades, the development of alternative approaches to synthetic pesticides is a requirement. Therefore, we used neem oil (NO) and ethanolic extracts (EE) from leaves at different concentrations to evaluate, in vitro, their insecticidal potentials against mirids. Mirid mortality increased significantly with increase in concentrations, values ranged from 32.5 to 92.5% for EE and 52.5 to 97.5% forNO. Apart from negative controls, Tween 80 and distilled water, that showed significant low mortality rates, both extracts revealed effectiveness comparable to the reference insecticide used in controlling mirids, except for EE by ingestion. Mirids treated by contact showed significantly high mortality rates (72.5 to 97.5 %) compared to those treated by ingestion (32.5 to 70.0 %). The greatest biological effectiveness values were obtained at a concentration of 8 % by contact exposure: 0.88 ml/ml (NO) and 0.73 g/ml (EE) for LC50 and =1 day to both extracts for LT50. Given effectiveness comparable to that of the insecticide, both tested extracts should be considered as effective biopesticides for IPM against mirids, especially S. singularis. more...
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- 2021
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49. Anthropic impacts on Sub-Saharan urban water resources through their pharmaceutical contamination (Yaoundé, Center Region, Cameroon)
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Elena Gomez, N. Ariza Castro, Jacques Gardon, Ives Magloire Kengne, Emmanuelle Cadot, David Sebag, Frédérique Courant, B. Ngounou Ngatcha, Perrine Branchet, Catherine Gonzalez, Hélène Fenet, Camille Jourdan, Laboratoire de Génie de l'Environnement Industriel (LGEI), IMT - MINES ALES (IMT - MINES ALES), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Hydrosciences Montpellier (HSM), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Morphodynamique Continentale et Côtière (M2C), Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), Observatoire de REcherche Méditerranéen de l'Environnement (OSU OREME), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Montpellier 2 - Sciences et Techniques (UM2), Département des Sciences de la terre, Department of Geology, University of Ngaoundere, Cameroon, Wastewater Research Unit, University of Yaounde I, Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Département des Sciences de la Terre [Univ Ngaoundéré] (UN-FS), Faculté de Sciences [Univ Ngaoundéré] (UN-FS), Université de Ngaoundéré/University of Ngaoundéré [Cameroun] (UN)-Université de Ngaoundéré/University of Ngaoundéré [Cameroun] (UN), University of Yaoundé [Cameroun], IMTMines Ales, HydroSciences Montpellier, Vicerrectoria de Investigacion y Extension del Instituto Tecnologico de Costa Rica, Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro) more...
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Water resources ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Sanitation ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,Wastewater ,010501 environmental sciences ,01 natural sciences ,Africa, Northern ,Water Supply ,Water Quality ,Urbanization ,11. Sustainability ,Environmental Chemistry ,[SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology ,Groundwater ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Sub-Saharan Africa ,Land use ,Water Pollution ,Pit latrine ,15. Life on land ,Pollution ,6. Clean water ,3. Good health ,Pharmaceutical Preparations ,13. Climate action ,Environmental science ,Pharmaceutical residues ,Water resource management ,Surface water ,Water Pollutants, Chemical ,Water use ,Environmental Monitoring - Abstract
(IF 5.59 [2018]; Q1); International audience; Sub-Saharan urban centers have to tackle high population growth, lack of sanitation infrastructures and the need for good quality water resources. To characterize the impacts of anthropization on the water resources of the capital of Cameroon (Yaoundé), a multi-disciplinary approach was used in ten sub-watersheds (peri-urban and urban) of the Méfou watershed. Pharmaceutical residues were used as tracers of surface and groundwater contamination caused by the release of domestic wastewater from pit latrines and landfills. A water use survey was conducted in the vicinity of the sampling sites to better assess water use, treatment and management. Available land use and hydro-geomorphological data completed characterization of the sub-watersheds. The combined data showed that natural features (elevation, slope, and hydrography) and human activities (land use) favor rainfall-runoff events and hence surface water contamination. Pharmaceutical monitoring revealed contamination of both surface and groundwater especially in the urban sub-watersheds. Analgesics/anti-inflammatory drugs and anti-epileptic carbamazepine were the most frequently found compounds (in up to 91% of water samples) with concentrations of acetaminophen reaching 5660 ng/L. In urban sub-watersheds, 50% of the groundwater sites used for drinking water were contaminated by diclofenac (476–518 ng/L), carbamazepine (263–335 ng/L), ibuprofen (141–276 ng/L), sulfamethoxazole ( more...
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- 2019
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50. Antibiotic susceptibility of four Enterobacteriaceae strains (Enterobacter cloacae, Citrobacter freundii, Salmonella typhi and Shigella sonnei) isolated from wastewater, surface water and groundwater in the equatorial zone of Cameroon (Central Africa)
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Yves Poutoum Yogne, Estelle Masseret, Sylvie Chinche Belengfe, Olive Vivien Noah Ewoti, Jean Samuel Eheth, Edith Brunelle Mouafo Tamnou, Paul Alain Nana, Télesphore Sime-Ngando, Awawou Manouore Njoya, Moïse Nola, Antoine Tamsa Arfao, Claire Stephane Metsopkeng, Luciane Marlyse Moungang, Faculté des Sciences - Yaoundé I, Université de Yaoundé I, Université de Douala, University of Buéa, MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Microorganismes : Génome et Environnement (LMGE), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Hydrobiology and Environment Laboratory, University of Yaounde 1, Faculty of Sciences, P.O. Box 812 Yaounde, Cameroon, Department of Oceanography and Limnology, Institute of Fisheries and Aquatic Sciences, University of Douala, Douala, Cameroon, Department of Fisheries and Aquatic Resources Management, Faculty of Agriculture and Veterinary Medicine, University of Buea, and Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut de Recherche pour le Développement (IRD) more...
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Antibiotic susceptibility ,biology ,Enterobacteriaceae species ,Cell’s abundance ,Abiotic factor ,Fosfomycin ,biochemical phenomena, metabolism, and nutrition ,Water system ,biology.organism_classification ,Salmonella typhi ,Enterobacteriaceae ,6. Clean water ,3. Good health ,Citrobacter freundii ,Microbiology ,Multiple drug resistance ,13. Climate action ,Cell's abundance ,[SDE]Environmental Sciences ,medicine ,Shigella sonnei ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,Enterobacter cloacae ,Antibiotic disc ,medicine.drug - Abstract
International audience; The health problems caused waterborne pathogens bacteria belonging to the Enterobacteriaceae family are aggravated by the rise of antimicrobial resistant bacteria phenomenon. This has been identified as one of the biggest global health challenges. The present study aims to make a comparative approach of the sensitivity/resistance to antibiotics of 4 Enterobacteriaceae Enterobacter cloacae, Citrobacter freundii, Salmonella typhi and Shigella sonnei isolated from wastewater, streams and groundwater in Yaounde town (Cameroon, Central Africa). Bacteria were isolated using standard methods their identification using the API 20E systems. The antibiogram tests were carried out using the Müller-Hinton antibiotic disc diffusion method. Results showed that inhibition diameters of antibiotic varied (P more...
- Published
- 2021
- Full Text
- View/download PDF
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