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Abstract Squaring, a wood transformation process, is an operation which consists of introducing the logs into a squaring machine which then uses sharp tools to cut the wood into pieces with high surface quality. Tool steels used in this process experience significant wear, damaging the wood surface and hence leading to substantial scrape rate. This study investigates the wear resistance of three tool steels specifically designed for wood cutting applications: modified AISI A8, modified steels with 0% and 1% tungsten, and powder metallurgy prepared W360 steel. Furthermore, the influence of a PVD coating on the wear resistance of the three alloys was investigated. ASTM G65 abrasive wear tests were conducted using the dry sand/rubber wheel abrasion test. A methodology using a non-contact 3D measurement system and specialized software was developed, allowing for a thorough quantitative assessment of the wear of these steels. The results revealed that the coated A8mod + 1%W steel exhibits the best resistance among the coated steels. Despite the excellent intrinsic resistance of W360 steel, the coating did not provide a significant improvement for this steel, showing only a 10% reduction in wear. Microstructural analysis revealed that the predominant wear mechanisms were abrasion and impact. The relative performance of each steel was quantified and is reported. Field trials conducted under actual cutting conditions, indicate the superiority of W360 steel in terms of resilience to wear and impacts compared to other tested alloys, while confirming the effectiveness of surface treatments in mitigating material wear. However, A8 steel modified with 1% tungsten exhibits increased wear under coating.

This paper discusses the efficient use of photovoltaic energy in areas with low solar irradiation. To extract the maximum power at low irradiation, we used a maximum power point tracking (MPPT) algorithm based on the combination of fuzzy logic (FL) and the sliding mode (SM) associated with a Proportionnel-Intégral (PI) regulator. The system parameters are calculated using the particle swarm optimization (PSO) technique, which thus ensures the stability of the controller. The performance of the proposed technique is compared with the conventional perturb and observe (P&O) technique in terms of tracking time and tracking efficiency at low irradiation. The simulation results prove that the technique has high tracking efficiency and less convergence time under low irradiation, with fewer power oscillations, low ripple and no overshoot.

IntroductionMany sampling methods are used for entomological surveillance of vector borne diseases. This paper, evaluated the performance of five methods with regard to various ecosystems encountered in Cameroon. Material and methodsTwo entomological databases generated during two study periods were examined: 2011-2014 in the North Region, and 2018-2019 in the Centre Region. Mosquitoes were collected using the (Human Landing Catches) (HLC) and four alternative methods including Clay Pots (CPs), Pyrethroid Spray Catches (PSCs), Window Exit Traps (WETs) and Centers for Disease Control-Light Traps (CDC-LTs) for which the performance was assessed in this study.ResultsA total of 29 anopheline species were identified from samples collected during the two study periods. All these anopheline species were found in North Region, with 5 species being the most abundant and prévalent, i.e. An. gambiae s.l, An. funestus, An. rufipes, An. paludis and An. pharoensis. In the Centre Region, only five species including An. gambiae s.l, An. funestus, An. coustani, An. ziemanni and An. paludis were recorded. Among these, An. gambiae s.l was the most abundant and prevalent species. Data confirmed HLC as the best in sampling outdoor and indoor mosquitoes in the surveyed HDs. The alternative methods showed variable records regarding the species richness. Based on the number of mosquitoes collected, CP was an alternative to HLC for outdoor collections in Garoua and Pitoa HDs, while WET was an alternative in Mayo Oulo HD. In the Centre Region, CDC-LT was an alternative to HLC for indoor collections in Ekié and Nkolbisson HDs, while PSC proved to be the best alternative in Nkolondom HD. Regarding the species richness WET appeared as an alternative to HLC in sampling outdoor mosquitoes in Garoua and Mayo Oulo HDs, while CP was the best alternative in Pitoa HD. In the Centre Region, CDC-LT was an alternative for outdoor and indoor collections in Nkolbisson HD, and the best alternative for outdoor collections in Ekie HD. Conclusion The current study revealed variable performance of the five tested adult mosquito collection methods across the prospected HDs in North and Centre Regions of Cameroon. Further investigations will be conducted on other collection methods, e.g., aspiration, mosquito electrocuting grid trap, ovitraps and human-baited double net trap.

Abstract Background Diabetic retinopathy is a leading cause of preventable blindness in Canada. Clinical guidelines recommend annual diabetic retinopathy screening for people living with diabetes to reduce the risk and progression of vision loss. However, many Canadians with diabetes do not attend screening. Screening rates are even lower in immigrants to Canada including people from China, Africa, and the Caribbean, and these groups are also at higher risk of developing diabetes complications. We aim to assess the feasibility, acceptability, and fidelity of a co-developed, linguistically and culturally tailored tele-retinopathy screening intervention for Mandarin-speaking immigrants from China and French-speaking immigrants from African-Caribbean countries living with diabetes in Ottawa, Canada, and identify how many from each population group attend screening during the pilot period. Methods We will work with our health system and patient partners to conduct a 6-month feasibility pilot of a tele-retinopathy screening intervention in a Community Health Centre in Ottawa. We anticipate recruiting 50–150 patients and 5–10 health care providers involved in delivering the intervention for the pilot. Acceptability will be assessed via a Theoretical Framework of Acceptability-informed survey with patients and health care providers. To assess feasibility, we will use a Theoretical Domains Framework-informed interview guide and to assess fidelity, and we will use a survey informed by the National Institutes of Health framework from the perspective of health care providers. We will also collect patient demographics (i.e., age, gender, ethnicity, health insurance status, and immigration information), screening outcomes (i.e., patients with retinopathy identified, patients requiring specialist care), patient costs, and other intervention-related variables such as preferred language. Survey data will be descriptively analyzed and qualitative data will undergo content analysis. Discussion This feasibility pilot study will capture how many people living with diabetes from each group attend the diabetic retinopathy screening, costs, and implementation processes for the tele-retinopathy screening intervention. The study will indicate the practicability and suitability of the intervention in increasing screening attendance in the target population groups. The study results will inform a patient-randomized trial, provide evidence to conduct an economic evaluation of the intervention, and optimize the community-based intervention.

In this work, we present a theoretical study and a numerical simulation on omnidirectional reflection in one-dimensional photonic crystal structures for a thermophotovoltaic device. The optical properties are determined using the transfer matrix method. The results show that the angular dependence of photonic bandgaps depends on refractive index contrast and, polarization. However, for both TE and TM polarization, a reflectivity peak with 100% reflectivity is observed. The Te/SiO2 structure is the one with the largest bandwidth of omnidirectional photonic band gap compared with the TiO2/SiO2 and Si/SiO2 structures. The results also show that by designing a giant birefringent optical the Brewster’s angle allows angle the control at any angle for both TE and TM mode.

Abstract Background Over the past two decades, Cameroon has recorded one of the highest rates of urban population growth in sub-Saharan Africa. It is estimated that more than 67% of Cameroon's urban population lives in slums, and the situation is far from improving as these neighbourhoods are growing at an annual rate of 5.5%. However, it is not known how this rapid and uncontrolled urbanization affects vector populations and disease transmission in urban versus rural areas. In this study, we analyse data from studies conducted on mosquito-borne diseases in Cameroon between 2002 and 2021 to determine the distribution of mosquito species and the prevalence of diseases they transmit with regards to urban areas versus rural areas. Methods A search of various online databases, such as PubMed, Hinari, Google and Google Scholar, was conducted for relevant articles. A total of 85 publications/reports were identified and reviewed for entomological and epidemiological data from the ten regions of Cameroon. Results Analysis of the findings from the reviewed articles revealed 10 diseases transmitted by mosquitoes to humans across the study regions. Most of these diseases were recorded in the Northwest Region, followed by the North, Far North and Eastern Regions. Data were collected from 37 urban and 28 rural sites. In the urban areas, dengue prevalence increased from 14.55% (95% confidence interval [CI] 5.2–23.9%) in 2002–2011 to 29.84% (95% CI 21–38.7%) in 2012–2021. In rural areas, diseases such as Lymphatic filariasis and Rift valley fever, which were not present in 2002–2011, appeared in 2012–2021, with a prevalence of 0.4% (95% CI 0.0– 2.4%) and 10% (95% CI 0.6–19.4%), respectively. Malaria prevalence remained the same in urban areas (67%; 95% CI 55.6–78.4%) between the two periods, while it significantly decreased in rural areas from 45.87% (95% CI 31.1–60.6%) in 2002–2011 to 39% (95% CI 23.7–54.3%) in the 2012–2021 period (*P = 0.04). Seventeen species of mosquitoes were identified as involved in the transmission of these diseases, of which 11 were involved in the transmission of malaria, five in the transmission of arboviruses and one in the transmission of malaria and lymphatic filariasis. The diversity of mosquito species was greater in rural areas than in urban areas during both periods. Of the articles reviewed for the 2012–2021 period, 56% reported the presence of Anopheles gambiae sensu lato in urban areas compared to 42% reported in 2002–2011. The presence of Aedes aegypti increased in urban areas in 2012–2021 but this species was absent in rural areas. Ownership of long-lasting insecticidal nets varied greatly from one setting to another. Conclusions The current findings suggest that, in addition to malaria control strategies, vector-borne disease control approaches in Cameroon should include strategies against lymphatic filariasis and Rift Valley fever in rural areas, and against dengue and Zika viruses in urban areas. Graphical Abstract

Abstract Background Diabetic retinopathy is a sight-threatening ocular complication of diabetes. Screening is an effective way to reduce severe complications, but screening attendance rates are often low, particularly for newcomers and immigrants to Canada and people from cultural and linguistic minority groups. Building on previous work, in partnership with patient and health system stakeholders, we co-developed a linguistically and culturally tailored tele-retinopathy screening intervention for people living with diabetes who recently immigrated to Canada from either China or African-Caribbean countries. Methods Following an environmental scan of diabetes eye care pathways in Ottawa, we conducted co-development workshops using a nominal group technique to create and prioritize personas of individuals requiring screening and identify barriers to screening that each persona may face. Next, we used the Theoretical Domains Framework to categorize the barriers/enablers and then mapped these categories to potential evidence-informed behaviour change techniques. Finally with these techniques in mind, participants prioritized strategies and channels of delivery, developed intervention content, and clarified actions required by different actors to overcome anticipated intervention delivery barriers. Results We carried out iterative co-development workshops with Mandarin and French-speaking individuals living with diabetes (i.e., patients in the community) who immigrated to Canada from China and African-Caribbean countries (n = 13), patient partners (n = 7), and health system partners (n = 6) recruited from community health centres in Ottawa. Patients in the community co-development workshops were conducted in Mandarin or French. Together, we prioritized five barriers to attending diabetic retinopathy screening: language (TDF Domains: skills, social influences), retinopathy familiarity (knowledge, beliefs about consequences), physician barriers regarding communication for screening (social influences), lack of publicity about screening (knowledge, environmental context and resources), and fitting screening around other activities (environmental context and resources). The resulting intervention included the following behaviour change techniques to address prioritized local barriers: information about health consequence, providing instructions on how to attend screening, prompts/cues, adding objects to the environment, social support, and restructuring the social environment. Operationalized delivery channels incorporated language support, pre-booking screening and sending reminders, social support via social media and community champions, and providing using flyers and videos as delivery channels. Conclusion Working with intervention users and stakeholders, we co-developed a culturally and linguistically relevant tele-retinopathy intervention to address barriers to attending diabetic retinopathy screening and increase uptake among two under-served groups.

Sustainable future development relies on solar radiation, which is the main source of renewable energy. Thus, in this article, the monthly average global solar irradiation of four sites in the Sudanian zone region of Chad is estimated using different empirical models. The data used in this study were collected at the General Directorate of Meteorology of Chad. The reliability and accuracy of six models estimating global solar radiation were validated and compared by statistical indicators identifying the most accurate model. The results obtained show that the Allen model has the best performance for the Moundou site (5.760 kWh/m²/d, R2=0.843), the Angstrom Prescott model for the Sarh sites (5.658 kWh/m²/d, R2=0.805) and Pala (5.793 kWh/m²/d, R²=0.889), the Sabbagh model for the Bongor site (5.657 kWh/m²/d, R²=0.888). These models are validated against NASA data. The results show that the Sudanian zone of Chad has good solar potential and is therefore suitable for possible exploitation.

In this paper, an Optimized Synergetic Nonlinear Controller (OSNC) is proposed to efficiently determine the maximum power point of a Photovoltaic Generator matched to the load through a DC–DC boost converter. The dynamic equation of the conventional synergetic controller is modified to adjust the Manifold in such a way that the optimum maximum power point (MPP) is reached. This new approach is implemented in the Matlab/Simulink software and shows increased convergence in steady and transient states. Consequently, this new approach exhibits better performance than the conventional nonlinear synergetic controller (SNC) in standard test conditions and weather varying conditions.

Aortoesophageal fistula (AEF) is an uncommon, but potentially fatal cause of upper gastrointestinal bleeding. Aortoesophageal fistulas caused by foreign body ingestion are rare but devastating. The classic clinical triad of AEF consists of mid-thoracic pain or dysphagia, a herald episode of hematemesis, followed by fatal exsanguination after a symptom-free period (Chiari’s triad). Computed tomography angiography (CTA) is the preferred diagnostic tool for identifying AEF and is substantially more sensitive than upper endoscopy for detecting AEF. Endoscopy can detect AEF as it might show pulsatile blood, pulsatile mass, hematoma, or adherent blood clot in the esophagus, or a deep esophageal tear. However, endoscopy has a low sensitivity and may delay definitive treatment. Several management options for AEF have been suggested; however, the definitive treatment is surgery performed on the thoracic aorta and esophagus, including esophagectomy, surgical replacement of the thoracic aorta, thoracic endovascular aortic repair, or omental flap. We report a case of a 63-year-old man who presented with hematemesis 2 weeks after chicken bone ingestion.

Managing information flow has always been a challenging and critical driver of performance increase in manufacturing companies. Each bit of information related to the manufacturing process has an information flow value that can impact the process. Recent studies have focused on the traditional classification algorithms methods to analyze the value of information flow. In this research paper, we use regression algorithms to develop an analytics model for the value of information flow in manufacturing shop floors of developing countries. The analysis shows that the Artificial Neural Network (ANN) has the best regression coefficient score of 0.775 with a prediction error of 0.0125. The lowest regression coefficient score of 0.323 was for the Multi-Linear Regression (MLR) with a prediction error of 0.0556. These results help companies use regression algorithms effectively to analyze the value of information flows on the manufacturing chains.

Attempts to prevent language endangerment seem to have overlooked how families proceed in surrendering the language whose intergenerational transmission is their main responsibility. The present paper envisages language maintenance or loss from the vantage point that beliefs about language are the main referents of language use in the family in multilingual settings, and can, therefore, explain the protracting process of language death. The data were collected through a questionnaire adapted from the BALLI [Horwitz, E. K. (1988). The beliefs about language learning of beginning university foreign language students. "Modern Language Journal," 72(3), 283-294.], which was administered in fifty families. These were then analysed through a logistical regression. The findings revealed, among many other things, a strong correlation between the referents people attribute to their indigenous languages and the likelihood of the use of those languages with their children. Some of these included ethnic language acquisition difficulty, the nature of mother tongue acquisition, transmission strategies, acquisition aptitude, and reward. Negative beliefs about indigenous languages, as well as lack of language consciousness as underscored by this study are real matters for concern as these beliefs, more than any other external factor, may accelerate the vanishing of indigenous languages in the world.

Objective: Mistake in diagnosis. Background: Pyogenic liver abscesses are collections of pus of varying sizes within the liver. They are rare and often overlooked in developed countries, and if left untreated, they can be life-threatening. Therefore, early detection and treatment are crucial for favorable outcomes. Due to the atypical presentation, a high level of suspicion is necessary, as seen in our patient's case. Case Report: This report pertains to a 76-year-old woman who was diagnosed with sepsis resulting from multiple hepatic abscesses. Initially, the abscesses were mistaken for metastatic breast cancer liver disease due to her history of breast cancer in remission for 3 years. However, further imaging and biopsy revealed the initial diagnosis to be incorrect. She had initially presented with nonspecific abdominal pain and diarrhea. The initial computed tomography (CT) scan of the abdomen indicated the development of extensive hepatic lesions, thought to be associated with breast cancer, but subsequent magnetic resonance imaging (MRI) suggested liver abscesses. Ultrasound-guided aspiration confirmed the presence of liver abscesses, and subsequent culture of the aspirate revealed the growth of Streptococcus intermedius. The patient responded well to a 4-week course of antibiotic therapy. Conclusions: This case report reviews the clinical presentation, risk factors, diagnosis, and management of multiple pyogenic liver abscesses, and shows the importance of using sound clinical reasoning in addressing diagnostic challenges of this nature. [ABSTRACT FROM AUTHOR]

Background. Hepatocellular carcinoma (HCC) is a leading cause of cancer morbidity and mortality. Findings of microvascular invasion (MVI) in patients with HCC have emerged as an important prognostic factor for poor survival after tumor resection. Aim. This study evaluated the relation between MVI and HCC within various anatomical Couinaud’s segments of the liver. Method. A multicenter retrospective review of HCC records was conducted from 2012 to 2017. HCC cases were identified using ICD-9 and 10 codes 155, C22.0, and C22.8. HCC patients who underwent liver transplants were included in this study. Liver segment of the location of HCC was obtained from radiographic records, and MVI information was obtained from pathology reports. Segmental distributions of HCC in MVI versus non-MVI groups were compared using Wilcoxon rank sum tests. p value was set at

This work demonstrated the potential of CNC as a substitute for PEG as an additive in ultrafiltration membrane fabrication. Two sets of modified membranes were fabricated using the phase inversion technique, with polyethersulfone (PES) as the base polymer and 1-N-methyl-2 pyrrolidone (NMP) as the solvent. The first set was fabricated with 0.075 wt% CNC, while the second set was fabricated with 2 wt% PEG. All membranes were characterized using SEM, EDX, FTIR, and contact angle measurements. The SEM images were analyzed for surface characteristics using WSxM 5.0 Develop 9.1 software. The membranes were tested, characterized, and compared for their performance in treating both synthetic and real restaurant wastewater. Both membranes exhibited improved hydrophilicity, morphology, pore structure, and roughness. Both membranes also exhibited similar water flux for real and synthetic polluted water. However, the membrane prepared with CNC gave higher turbidity removal and COD removal when raw restaurant water was treated. The membrane compared well with the UF membrane containing 2 wt% PEG in terms of morphology and performance when synthetic turbid water and raw restaurant water were treated.