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Runoff in mountain areas is an increasingly worrying environmental problem. In the Nkam watershed where we observe a greater change in the landscape, it is at the origin of certain phenomena such as soil erosion, floods and mud flow. It increasingly reduces arable land, decreases the capacity of water reservoirs and weakens the income of the populations. Based on this observation, this article assesses the susceptibility of the soils in this basin to runoff. The evaluation method developed to carry out this investigation combines the Geographic Information System (GIS) with the Soil Conservation Services Curve Number (SCSCN) method, based on the physical characteristics, land use and hydrological conditions of the soils used. With these, the soil, slope and land use maps were produced and superposed to determine how sensitive the soils are to runoff. The results obtained indicate that 58% of the basin is made up of slopes> 15%, the soils are made up of easily weathered minerals and the rate of forest regression is -2.79% per year between 1978 and 2019. The combination of these three factors indicates that soils in the study area have reached a worrying threshold of exposure to runoff (CN = 67). Reforestation and no-till cultivation techniques upstream of the basin would mitigate the runoff effect.

The use of Information and Communication Technology (ICT) in the energy sector is becoming increasingly common. From data collection, recording and dissemination of energy information to design, planning and management of energy systems, scientific computing skills and tools, amount them programming languages. Depending on the problem to be solved, the choice of programming language is often very decisive for achieving the expected results. This article presents an analysis of the state of art of programming languages used in the energy domain and propose a case study of the programming languages to be used depending on the problem to be solved renewable energies sector. Programming languages for scientific computing are divided into two main classes: General Purpose Languages (GPL) and Domain Specific Languages (DSL); knowing a GPL make one better at using DSL. The analysis carried out shows that in energy engineering, the most used GPLs are C++ and python. Likewise, the most prominent DSLs are Julia, R and Matlab. The most suitable language for scientific computing, data science, visualization, and high-performance computing problems is Python. However, Julia which is in full expansion is not to be overlooked as it is dedicated to energy.

Many non-electrified rural communities find it challenging to follow a precise scientific protocol to assess the feasibility of installing a wind turbine on their site. The objective of the present work is to define a clear protocol for the assessment of wind potential of a rural site. The case of Logone Birni (LB) is taken as a case study. For this purpose, a protocol, integrating the wind parameters of the site have been used to calculate the wind power density, annual energy yield, and capacity factors at 10, 30, and 50 m height using 15 years data. The wind frequency distribution including seasonal has been investigated to determine accurately the wind power of the site. The coefficient of variation is calculated at three different heights. Also, an economic assessment per kWh of energy has been carried out. The results of this study show that it is possible to install a wind farm in LB site with a minimum of 30m height. In addition, wind turbines with a starting speed of 1.5 m/s and a rated power of 20 kW will produce electricity at a low cost (0.453USD/kWh).

Biogas is an ideal fuel for sustainable energy and an alternative to wood energy in sub-Saharan Africa. Its valorisation in rural areas is limited to cooking despite its enormous potential for electricity production. However, the inaccessibility of biogas analyzers to assess the quality of biogas and trigger its use in an engine is one of the main obstacles to this new trend. The aim of this work is to develop a simple and inexpensive portable digital device capable of analysing any biogas together with its production parameters. To achieve this, a prototype analyser using an Arduino card fitter with sensors was designed and built, then experimented with biogas produced from cow dung. Sampling tests were carried out after 4 and 10 days of loading 10-liter bioreactors with cow dung. A Better flammable biogas production was recorded at 10 days of loading with 66.41% methane (CH4), 32.43% CO2, and 1.14% water vapour (H2O). This biogas analyser was quite efficient and could identify gases produced by the methanization process while controlling the bioconversion parameters. Nonetheless, the biogas obtained can be purified for more efficient use.

INTRODUCTION: The number of HIV exposed uninfected (HEU) infants is increasing as vertical transmission is reducing. This subpopulation requires more investigations. This study aimed at comparing the expression level of soluble Fas receptors (FasR) and ligands (FasL) between HIV infected, HEU and unexposed children. METHODS: eighty eight HIV-1infected, 86 HEU and 38 HIV unexposed children were recruited. Soluble FasR and FasL were measured in their plasma. Mann-Whitney U-Test was used to compare groups with 95% confidence. Spearman coefficient was used to test the correlation with CD4 and viral load (VL). RESULTS: overall plasma levels of FasR were higher than that of FasL. The concentration of FasR and FasL were significantly higher in HIV-1 infected children in comparison to HEU and unexposed children. There was no difference in the plasma level of FasL in HIV infected compared to HEU children. A significant difference was observed between HIV infected children and HEU children (P=0.001) for the FasL. FasR were higher in both HIV infected and unexposed children compared to HEU children. There was a positive correlation (rs=+0.4; p=0.01) in ARV treated children between CD4 count and FasL concentration. Significant negative correlation (rs=-0.3; p=0.040) in ARV naive children was observed between CD4 percentage and FasL. Significant and positive correlation (rs=+0.4; p=0.008) was observed between the VL and FasL in HIV infected, treated or not. CONCLUSION: HEU children differ from HIV infected and unexposed children as the level of FasL/R expression is concerned. HEU should be considered different from HIV unexposed although exempt from virus as some immune dysfunctions have been reported among them.

The manual extracapsular extraction of the lens is the surgical technique that is most practiced for the treatment of cataract in sub-Saharan Africa. Learning this technique requires the creation of a surgical simulation unit within training institutes. We describe the development stages of a traditional simulation unit. For this purpose, we present a description of four steps involved in the development of a simulation unit for cataract surgery: the physical creation of the room, the aseptic and antisepsis conditions, the management of the eyes, the development of a curriculum and the administrative policies.

Although widely reported in children, the malarial retinopathy has rarely been described in adults. We observed a case in the department of ophthalmology at the pediatric and gynecology-obstetrics Yaoundé Hospital. The diagnosis revealing a decrease in visual acuity was confirmed by thorough ophthalmological and biological assessments. The basic treatment by quinine therapy was conclusive. The authors point out the need to consider this diagnosis in case of any decrease in visual acuity in febrile context for any adult living or recently having stayed in endemic areas.

La fistule carotido-caverneuse indirecte est une communication anormale entre de multiples artérioles provenant des branches durales ou méningées de l'artère carotide externe et/ou de l'artère carotide interne et le sinus caverneux. Son diagnostic de certitude a recours à l'artériographie carotidienne, mettant en évidence la fistule. Or, cet examen n'est pas disponible dans notre contexte d'exercice, d'où l'intérêt des signes indirects cliniques (exophtalmie avec dilatation des vaisseaux conjonctivaux en tête de méduse) et de l'angio scanner cérébral (dilatation de la veine ophtalmique supérieure) pour évoquer le diagnostic et éliminer les différentiels (tumeur orbitaire, exophtalmie thyroïdienne, pseudo tumeur inflammatoire, etc.). Nous rapportons le cas, d'un patient âgé de 58 ans venu consulter pour exophtalmie et baisse d'acuité visuelle gauche progressive évoluant depuis un an. Son histoire rapportait un traumatisme orbitaire gauche lors d'un accident de la voie publique trois ans plus tôt. L'exophtalmie gauche était axile, réductible, non pulsatile, sans souffle audible, indolore, sans limitation des mouvements oculaires, ni adénopathie satellite (A). L'�il gauche avait une acuité visuelle de 1/10 P10, une hypertonie à 28 mmHg, les vaisseaux conjonctivaux et rétiniens étaient dilates (A, B). L'examen de l'�il droit et le bilan thyroïdien étaient normaux. L'angio-scanner cérébral montrait une dilatation de la veine ophtalmique supérieure gauche (C). L'insuffisance du plateau technique, sur le plan endovasculaire donnant recours à une embolisation, nous a obligés à faire une prise en charge symptomatologique: larme artificielle et collyre hypotenseur.

We carried out a cross-sectional analytical survey using data from patients who had done Fluorescein Angiography at the Yaounde Central Hospital Diabetic Retinopathy Prevention and Management Project between October 2007 and January 2010 to identify the risk factors, incidence and severity of different types of diabetic retinopathy. Data from 239 males (57.0%) and 180 females (43.0%) with diabetic retinopathy were included. Their mean age was 58.2 years. A majority of them were living with type II diabetes (96.2%). The mean duration of diabetes was 8.2 years. About sixty percent had both diabetes and hypertension. The average level of glycated haemoglobin was 9.72% (range 6-17.7%). Amongst the 419 patients with diabetic retinopathy, 292(69.7%) had non-proliferative diabetic retinopathy. One hundred and twelve (26.7%) of those with proliferative diabetic retinopathy had a formal indication for laser photocoagulation. Fifteen patients (3.6%) presented with complicated forms of proliferative diabetic retinopathy. Diabetic maculopathy was present in 30 patients (7.2%). Diabetic retinopathy is a frequent complication of diabetes in our setting which stems from inadequate emphasis on preventive measures. The technical requirements for managing some of the existing complications are still unavailable. Fluorescein Angiography is an important diagnostic tool which should be popularized.

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In Cameroon, local forestry practices are sometimes not in line with the legal requirements related to selling timber from community forests (CFs). The purpose of this study was to evaluate local practices based on the requirements of legality grid No. 6 from the VPA-FLEGT (Voluntary Partnership Agreement – Forest Law Enforcement, Governance and Trade). Focus group discussions, individual interviews, and field observations revealed that local practices in CF could be compatible with the requirements of the grid. However, some local practices contribute to preventing fulfillment of VPA-FLEGT requirements. To bridge the gaps between local practices and grid verifiers, the grid could be modified to better distinguish the responsibilities of communities, contractors, and the forest administration. This would allow for the modification of forest legislation to prevent overburdening communities. Another option would be to develop a market strategy for legal wood from CFs. Results from this study could find applications in other countries where VPA-FLEGT have been implemented or are negotiated in Africa, Asia, Central America, and South America. [ABSTRACT FROM AUTHOR]

The indirect carotido-cavernous fistula is an abnormal communication between multiple arterioles coming from dural or meningeal branches of the external carotid artery and/or of the internal carotid artery and the cavernous sinus. Its definitive diagnosis relies on carotid angiography showing the fistula. This imaging procedure is not available in our medical context, hence the importance of clinical indirect signs (exophthalmos with Medusahead dilatation of the conjunctival vessels) and of CT angiography of the brain (dilation of the superior ophthalmic vein) to suggest the appropriate diagnosis and eliminate differential diagnosis (orbital tumor, thyroid exophthalmos, pseudo inflammatory tumor, etc.). We report the case of a 58-year old patient who presented with exophthalmos and progressive vision loss in the left eye which had evolved over the previous year. The patient had a history of left orbital trauma caused by road accident three years before. Left exophthalmos was axile, reducible, non-pulsatile, with no audible breath, painless, without limitation of the eye movements and satellite adenopathy (A). The left eye conjunctival and retinal vessels were dilated (A, B). Right eye examination and thyroid function were normal. CT angiography of the brain showed enlarged left superior ophthalmic vein (C). The insufficiency of technical equipment, endovascular status suggesting embolization forced us to make symptom management: artificial tear and hypotensive eye drops. [ABSTRACT FROM AUTHOR]