The conversion of forest land to other types of land cover is one of the major issues in the global fight against climate change. Understanding the direct and indirect factors of these conversions from local studies i...The conversion of forest land to other types of land cover is one of the major issues in the global fight against climate change. Understanding the direct and indirect factors of these conversions from local studies in the tropics is essential to project the future impact of human activities on the preservation of tropical forests in general and the forests of the Republic of Congo in particular. This study, conducted in five localities with different socioeconomic contexts in the Republic of Congo, aims to analyze the variability of drivers of deforestation and forest degradation linked to urbanization in the Congo Basin. Using a series of land cover maps from the years 1986, 2003 and 2019 for the cities of Ouesso, Pokola, Ngombe, Impfondo and Dongou, as well as field data and socio-economic information collected from local and central administrations, a unique model has been developed to understand the explanatory patterns of forest loss. Deforestation around urban centers is mainly due to urban agriculture due to population growth, as well as the spatial expansion of cities, which have a major impact on the stability and integrity of forests. Shifting agriculture is the main direct cause of deforestation and forest degradation, representing 48% of the total sample, followed by the collection of wood fuel (22%), the collection of construction wood (19%), illegal logging (6%) and urban expansion (5%). Forecasts indicate that forest loss around major cities will increase by 487, 20 ha to 5266, 73 ha by 2050 compared to the base year of 2019. This study highlights the need for a new system of land management and poverty alleviation of local populations to ensure the stability of the Congo Basin tropical forests around large and small African cities.展开更多
One of the most promising vector control strategies for controlling dengue fever is the stable introduction of the obligate intracellular Wolbachia bacteria strain into Aedes aegypti mosquitoes. This method reduces th...One of the most promising vector control strategies for controlling dengue fever is the stable introduction of the obligate intracellular Wolbachia bacteria strain into Aedes aegypti mosquitoes. This method reduces the mosquito’s ability to transmit dengue through reproductive strategies associated with Wolbachia infection, such as parthenogenesis, male elimination or feminization, sex ratio distortions and cytoplasmic incompatibility. Expert knowledge and a risk assessment framework were used to identify the risks associated with the release of Wolbachia-bearing mosquitoes. Then, consultations with individual participants were organized and a Bayesian network (BN) was developed to capture the relationship between the hazards as well as the likelihood of these adverse events occurring. Finally, risk was calculated from the probability and consequence estimates obtained from our Burkina Faso participants, using a questionnaire based on the identified risks. Our “Cause More Harm” study yielded 46.15% negligible risk, 44.23% very low risk and 9.62% low risk. The “socio-cultural change” parameter had the greatest influence, with the perception that the dissemination project would be poorly received by the local population. This parameter alone accounted for 80% of the most significant risks. This explains the fact that hazard RA 49 “negative messages in social media” is ranked as the highest individual risk (although the risk is low) with a calculated risk of 0.261. The risk assessment was designed to integrate the interdependent complexity of hazards likely to affect the dissemination of technology in the environment. It represents an important implementation phase in the success of this innovative research, introducing a new technology to combat the transmission of dengue fever.展开更多
In Burkina Faso, recent dengue outbreaks were exacerbated by Aedes aegypti mosquitoes, which have developed resistance to conventional insecticides. This study investigates the potential of Metarhizium pingshaense Met...In Burkina Faso, recent dengue outbreaks were exacerbated by Aedes aegypti mosquitoes, which have developed resistance to conventional insecticides. This study investigates the potential of Metarhizium pingshaense Met_S26, a fungus from Burkina Faso, for controlling both endophilic and exophilic Aedes mosquitoes. Traditional interventions are less effective against mosquitoes resting outdoors, and the ability of the fungus to be sexually transmitted could enhance its efficacy. Aedes mosquitoes were reared and exposed to various concentrations of Metarhizium pingshaense to assess its virulence. The fungus showed significant efficacy, with lethal times (LT80) ranging from 8.67 to 11.83 days depending on the concentration. Furthermore, bioassays demonstrated effective sexual auto-dissemination, with substantial transmission of fungal spores between infected and uninfected mosquitoes, leading to lower survival rates in uninfected mates. This study highlights Metarhizium pingshaense Met_S26 as a promising tool for controlling both indoor and outdoor Aedes populations, complementing existing vector control strategies such as the Sterile Insect Technique (SIT) and Wolbachia-based approaches. Future research should explore integrating this fungus with other control methods for a comprehensive vector management strategy.展开更多
Solar stills represent a promising solution for desalinating saline waters, providing a sustainable alternative in regions with limited access to drinking water. This study evaluates the reliability of a two-dimension...Solar stills represent a promising solution for desalinating saline waters, providing a sustainable alternative in regions with limited access to drinking water. This study evaluates the reliability of a two-dimensional (2D) numerical model of a solar still, developed using COMSOL® Multiphysics software, focusing on a passive cascading device called “Pano Rano.” Two physical prototypes were constructed: one with a standard concrete basin and the other with acrylic plastic. The simulations revealed significant differences in theoretical yield based on the material used. With a radiation of 1200 W/m2, the acrylic prototype displayed an evaporation of 4455.53 mL/m2 and a production of 2925.98 mL/m2 of distilled water, while the concrete model showed an evaporation of 2109.95 mL/m2 and produced 1383.93 mL/m2 of distilled water. The results indicate that evaporation significantly exceeds condensation, highlighting an underutilized evaporation potential. The evaluation of the numerical model’s performance against experimental results was conducted using the mean squared error (MSE) and the coefficient of determination (R2). The best performance was observed in summer (MSE of 16.24;R2 of 0.95), while winter results were less convincing (MSE of 204.77;R2 of −2.78). This variability underscores the model’s limitations and the need for future research. The study also demonstrates that the choice of basin material significantly influences productivity, with acrylic plastic outperforming concrete in terms of thermal efficiency.展开更多
The pervasive use of photo editing applications such as Photoshop and FaceTune has significantly altered societal beauty standards, particularly for individuals with skin of color, often leading to unrealistic expecta...The pervasive use of photo editing applications such as Photoshop and FaceTune has significantly altered societal beauty standards, particularly for individuals with skin of color, often leading to unrealistic expectations regarding skin appearance and health. These tools allow users to smooth skin textures, lighten skin tones, and erase imperfections, perpetuating Eurocentric beauty ideals that frequently marginalize the natural diversity of skin tones and textures. Consequently, individuals with skin of color may seek dermatological interventions—such as skin lightening treatments, aggressive acne scar revisions, and other cosmetic procedures—aimed at achieving appearances that align more closely with digitally manipulated images. This pursuit of an unattainable aesthetic can result in increased dissatisfaction with common skin conditions like hyperpigmentation and keloids, which are often misrepresented in edited photos. Additionally, the psychological impact of these alterations can exacerbate feelings of inadequacy, contributing to conditions such as anxiety and body dysmorphic disorder. Dermatologists face the dual challenge of addressing patients’ clinical needs while also managing their expectations shaped by digital enhancements. To combat this, it is essential for dermatologists to integrate patient education that emphasizes the beauty of diverse skin tones and the discrepancies between digital images and authentic skin health. By fostering an understanding of realistic outcomes and promoting the acceptance of natural skin characteristics, dermatologists can empower individuals with skin of color to prioritize authentic skin health over digitally influenced ideals, ultimately leading to more satisfying dermatological care and improved self-image.展开更多
Background: Malnutrition, a serious public health concern, is influenced by various factors. Objective: The study aims to explore malnutrition issues among infants under five years old in Guéra Province. Methods:...Background: Malnutrition, a serious public health concern, is influenced by various factors. Objective: The study aims to explore malnutrition issues among infants under five years old in Guéra Province. Methods: The study used a cross-sectional design and a two-stage cluster sampling method to select participants. The study population was infants aged between 0 - 24 months. Data collection was done between June 2023 and September 2024;it included anthropometric measurements, blood analyses, and interviews. Anthropometric parameters were calculated using ENA for SMART software. Statistical analyses were performed by R Studio to investigate associations between different characteristics, using logistic regression models to identify risk factors. A p-value less than 0.05 was considered significant. Results: The study included 377 infants in eight villages in Guéra Province, Chad. The sample was predominantly girls (55.3%), with a median age of 16 months. Most infants (94%) were mixed-fed, and only 6% were exclusively breastfed. We found that 7.3% of children were globally malnourished, with higher rates in boys 9.6%. A significant disparity existed between boys and girls in global acute malnutrition (GAM) rates, with boys having a higher prevalence of 17.9%. A substantial proportion of Infants were underweight, with males 27.4%. Stunting was prevalent 20.1%. Several factors were associated with malnutrition, including gender, feeding practices, infectious diseases, and socioeconomic factors. Diarrhea, malaria, limited access to drinking water, and early diet diversification were significantly associated with malnutrition. Conclusion: Targeted interventions are necessary to address these issues and improve the nutritional status of children in the Guéra province.展开更多
The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method f...The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method for infrared and visible image fusion is proposed.The encoder designed according to the optimization objective consists of a base encoder and a detail encoder,which is used to extract low-frequency and high-frequency information from the image.This extraction may lead to some information not being captured,so a compensation encoder is proposed to supplement the missing information.Multi-scale decomposition is also employed to extract image features more comprehensively.The decoder combines low-frequency,high-frequency and supplementary information to obtain multi-scale features.Subsequently,the attention strategy and fusion module are introduced to perform multi-scale fusion for image reconstruction.Experimental results on three datasets show that the fused images generated by this network effectively retain salient targets while being more consistent with human visual perception.展开更多
Introduction: Influenza A (Flu A) and B (Flu B) viruses are responsible for severe acute respiratory infections (SARI) worldwide, with a morbidity of 5 million and mortality of 29,000 - 650,000 deaths per year. Influe...Introduction: Influenza A (Flu A) and B (Flu B) viruses are responsible for severe acute respiratory infections (SARI) worldwide, with a morbidity of 5 million and mortality of 29,000 - 650,000 deaths per year. Influenza B viruses are an important cause of respiratory infections in humans, but they tend to be underappreciated due to the predominance of Influenza A. No molecular study on Influenza B has been carried out in the DRC. This study was conducted to document the molecular evolution of the hemagglutinin (HA) gene in the circulating Influenza B strains over the eight consecutive epidemic seasons (from 2015 to 2022). Methods: Samples were collected from outpatient cases suspected of influenza-like illness (ILI) and in all hospitalized patients with SARI from January 2015 to December 2022. Molecular analysis was done to determine influenza type and subtype, and then segments encoding the HA gene of Influenza B viruses were performed. Results: Of 8497 samples collected and tested, 639 (7.5%) were positive for influenza viruses, including 389 (60.8%) for Influenza A viruses and 248 (38,8%) for Influenza B viruses. Of the positive Influenza B samples, 91 were sequenced, including 26 belonging to the B/Yamagata lineage and 65 to the B/Victoria lineage. The HA gene of Influenza B viruses circulating in the DRC showed deletions in the HA1 region. Molecular analysis of Influenza B viruses reflects the genetic diversity of Influenza B/Yam virus clades (Y2, Y3, Y3V1A) alternating with Influenza B/Victoria virus clades (V1A, V1A.3) depending on the year and influenza seasons. The phylogenetic analysis of these Influenza B strains shows compatibility with the corresponding vaccine strains that the WHO had validated for each influenza season. Conclusion: This study underscores the importance of continuous molecular surveillance of Influenza B viruses in the DRC to understand their epidemiology and evolutionary dynamics. Identifying mutations, such as HA deletions, is critical for assessing their impact on transmissibility vaccine efficacy and guiding effective vaccination and control strategies.展开更多
This study examines hemodynamic behavior in particular cases of pulmonary hypertension without treatment. Pulmonary hypertension represents an anomalous hemodynamic state and is characterized by an excessively high bl...This study examines hemodynamic behavior in particular cases of pulmonary hypertension without treatment. Pulmonary hypertension represents an anomalous hemodynamic state and is characterized by an excessively high blood pressure in the pulmonary artery. To simulate the hemodynamic abnormalities in pulmonary hypertension under different causes and pathologies, we construct a localized parameter circuit model governed by nonlinear ordinary derivative equations of the human circulatory system. Thus, two special cases are considered, namely pulmonary the artery stenosis and the left ventricular diastolic dysfunction. For each case of pulmonary hypertension development, we determine the relationships between blood pressure and chamber and vessel pressure-volume. When the pulmonary hypertension is due to pulmonary artery stenosis, it appears that the right ventricular pressure increases up to 90 mm Hg, likewise the rise in pulmonary artery resistance induces direct increment in pulmonary artery pressure. However, when the pulmonary hypertension is due to left ventricular diastolic dysfunction, we note that the left atrial pressure and the pulmonary vein pressure augment, leading to the growth of the pulmonary artery blood pressure. The established results within this paper are useful for understanding the hemodynamic mechanism of particular pulmonary hypertension.展开更多
Background: Riedel’s thyroiditis is a rare form of chronic inflammatory disease affecting the thyroid gland. It is characterised by the replacement of the thyroid parenchyma by fibrous tissue. It also affects the adj...Background: Riedel’s thyroiditis is a rare form of chronic inflammatory disease affecting the thyroid gland. It is characterised by the replacement of the thyroid parenchyma by fibrous tissue. It also affects the adjacent vital structures. Due to its characteristic presentations, Riedel’s thyroiditis may not be immediately diagnosed. Objectives: Through this clinical case, we aimed to describe the pathology and clinical characteristics of Riedel’s thyroiditis and the diagnostic, therapeutic, and progressive modalities. Methods: A 62-year-old woman with no particular pathological history is consulted at the outpatient clinic for anterior cervical swelling that has been present for more than 5 years and is associated with respiratory discomfort and dysphagia to solids. Clinical examination, ultrasound, lab tests and injected cervical computed tomography (CT) were performed. These tests were completed with pathological examination. Results: General conditions were normal. Anterior cervical swelling, marked on the right, of hard consistency, causing cervical shielding with healthy surrounding skin, was observed at the examination. A compressive goitre was first suspected. Thyroid tests showed hypothyroidism. The CT revealed a hypodense goitre with micro-calcifications developed at the expense of the right lobe and exerting a mass effect on the trachea and oesophagus. Aspiration thyroid was not conclusive given the suspicion of the malignant nature of the goitre, and the decision to perform a right loboisthmectomy was taken. Pathological examination of the biopsy showed atrophy of the thyroid parenchyma with dense septal fibrosis punctuated by lymphocytes and extending throughout the tissue associated with inflammation—an appearance in favour of Riedel’s thyroiditis. The patient was treated with Levothyroxine and corticoids. Conclusions: This case points out the challenges in diagnosing Riedel’s Thyroiditis and the complexity of the pathology that requires a rigorous diagnostic approach and appropriate treatment for the best outcome.展开更多
Introduction: Arbovirus diseases such as dengue and chikungunya threaten public health worldwide. Early and rapid diagnosis and surveillance of dengue virus (DENV) and chikungunya virus (CHIKV) infections are essentia...Introduction: Arbovirus diseases such as dengue and chikungunya threaten public health worldwide. Early and rapid diagnosis and surveillance of dengue virus (DENV) and chikungunya virus (CHIKV) infections are essential to the control of these diseases. In this study, we evaluate the diagnostic performance of our new in-house multiplex RT-qPCR method for detecting DENV serotypes and CHIKV in an external laboratory. Methodology: The evaluation study was conducted on 200 clinical samples of suspected patients for arbovirus disease infection, collected in Centre de Recherche Biomoléculaire Pietro Annigoni (CERBA), Ouagadougou, Burkina Faso. Our new multiplex RT-qPCR was compared to the commercial kit, the Zika, Dengue, and Chikungunya (ZDC) Real-Time PCR Assays kit (Bio-Rad, California, USA). Results and Conclusions: Among 200 samples, 21.5% (43/200) were DENV-positive by multiplex RT-qPCR, and 21.5% (43/200) were also DENV-positive by reference real-time RT-PCR. 157 (78.5%) samples tested negative for DENV by both tests (new mRT-qPCR and reference test). The sensitivity and specificity of mRT-qPCR were 100%. The DENV serotypes detected were DENV-1 60.5% (26/43) and DENV-3 39.5% (17/43). CHIKV was not detected in this study. Our new mRT-qPCR is sensitive, cost-effective, simple, and can be used in developing country laboratories.展开更多
One of the main objectives of artificial intelligence lies in the simulation of the behavior of living organisms;emotions are a fundamental part of life, and they cannot be left aside when simulating behavior. In this...One of the main objectives of artificial intelligence lies in the simulation of the behavior of living organisms;emotions are a fundamental part of life, and they cannot be left aside when simulating behavior. In this research, software is developed that simulates the behavior of birds with different characteristics. The latter interacts by considering different stimuli from the environment (external), and the internal state of the subject (objectives). To achieve this, a model of birds in the role of prey and predators is developed that focuses on the study of the interaction between these organisms that exhibit specific behaviors in their environment. This project is a seminal work that aims to represent the emotions of birds, and the latter caused by stimuli from a dynamic environment.展开更多
This study develops an analytical model to evaluate the cooling performance of a porous terracotta tubular direct evaporative heat and mass exchanger. By combining energy and mass balance equations with heat and mass ...This study develops an analytical model to evaluate the cooling performance of a porous terracotta tubular direct evaporative heat and mass exchanger. By combining energy and mass balance equations with heat and mass transfer coefficients and air psychrometric correlations, the model provides insights into the impact of design and operational parameters on the exchanger cooling performance. Validated against an established numerical model, it accurately simulates cooling behavior with a Root Mean Square Deviation of 0.43 - 1.18˚C under varying inlet air conditions. The results show that tube geometry, including equivalent diameter, flatness ratio, and length significantly influences cooling outcomes. Smaller diameters enhance wet-bulb effectiveness but reduce cooling capacity, while increased flatness and length improve both. For example, extending the flatness ratio of a 15 mm diameter, 0.6 m long tube from 1 (circular) to 4 raises the exchange surface area from 0.028 to 0.037 m2, increasing wet-bulb effectiveness from 60% to 71%. Recommended diameters range from 5 mm for tubes under 0.5 m to 1 cm for tubes 0.5 to 1 m in length. Optimal air velocities depend on tube length: 1 m/s for tubes under 0.8 m, 1.5 m/s for lengths of 0.8 to 1.2 m, and up to 2 m/s for longer tubes. This model offers a practical alternative to complex numerical and CFD methods, with potential applications in cooling tower optimization for thermal and nuclear power plants and geothermal heat exchangers.展开更多
This work aims at the mathematical modeling of a parabolic trough concentrator, the numerical resolution of the resulting equation, as well as the simulation of the heat transfer fluid heating process. To do this, a t...This work aims at the mathematical modeling of a parabolic trough concentrator, the numerical resolution of the resulting equation, as well as the simulation of the heat transfer fluid heating process. To do this, a thermal balance was established for the heat transfer fluid, the absorber and the glass. This allowed us to establish an equation system whose resolution was done by the finite difference method. Then, a computer program was developed to simulate the temperatures of the heat transfer fluid, the absorber tube and the glass as a function of time and space. The numerical resolution made it possible to obtain the temperatures of the heat transfer fluid, the absorber and the glass. The simulation of the fluid heating process was done in one-hour time steps, from six in the morning to six in the afternoon. The results obtained show that the temperature difference between the inlet and the outlet of the sensor is very significant. These results obtained, regarding the variation of the temperatures of the heat transfer fluid, the absorber and the glass, as well as the powers and efficiency of the parabolic trough concentrator and various factors, allow for the improvement of the performances of our prototype.展开更多
The iTrace Dysfunctional Lens Index (DLI) offers a quantitative approach to lens assessment, potentially facilitating the early detection of cataracts. Globally, the prevalence of cataracts has increased due to aging ...The iTrace Dysfunctional Lens Index (DLI) offers a quantitative approach to lens assessment, potentially facilitating the early detection of cataracts. Globally, the prevalence of cataracts has increased due to aging populations, and in Morocco, they remain a significant cause of reversible blindness. This study examines the specificity and sensitivity of the DLI in identifying cataracts among a large sample of patients, focusing on differentiating early-stage cataracts from other conditions that affect visual quality. The DLI, which generates a score from 0 to 10, provides an objective lens quality measure, with lower values indicating dysfunction. In a cohort of 621 patients (1242 eyes), 243 eyes displayed a DLI < 5. Of these, 56 eyes had confirmed cataracts and 187 eyes presented with various ocular conditions but clear lenses. The results demonstrate 100% sensitivity for identifying cataracts within the DLI < 5 threshold, with a specificity of 72.4%. These findings highlight the utility of DLI as a diagnostic tool for early-stage cataracts despite variability influenced by ocular characteristics such as axial length and keratoconus.展开更多
Objective: Pregnancy in a scarred uterus is considered to be high-risk, especially during parturition. Nevertheless, the literature favours vaginal delivery as long as obstetric conditions are favourable. The aim of o...Objective: Pregnancy in a scarred uterus is considered to be high-risk, especially during parturition. Nevertheless, the literature favours vaginal delivery as long as obstetric conditions are favourable. The aim of our study was to contribute to the improvement of delivery management for women with scar uteri at the CHU Communautaire. Methodology: This was a cross-sectional study conducted over an 18-month period from 01 January 2020 to 30 June 2021 on women with scar uterus who came to give birth at the CHU Communautaire maternity unit. The sample was exhaustive;any parturient with a history of scarred uterus of more than one year with a clinically normal pelvis and whose fetus was in cephalic presentation. The following were excluded from the study: pregnant women with a uterine scar of less than one year, fetuses in a non-cephalic vertex presentation, pregnant women with antecedent complicated childbirth at the previous cesarean section, large fetuses informed consent had been obtained from the pregnant women. Anomynia was respected throughout the study. Results: During this period, we recorded 205 parturients with a scar uterus. The incidence of delivery with a scar uterus was 9.5%. Uterine testing was attempted in 85.9% of cases, with a success rate of 75.6%. Factors predictive of a successful uterine test was: maternal age less than 35 years (P = 0.0027), entry into labour at the reference maternity hospital (P Conclusion: Delivery with a scarred uterus is an increasingly frequent occurrence at the Maternity Unit of the CHU Communautaire in Bangui. Uterine testing is the first option if conditions allow, but careful selection of candidates during antenatal care or at the very beginning of labour is necessary for this type of delivery.展开更多
Burundi faces major agricultural constraints, including land fragmentation, soil erosion, limited access to inputs, inadequate infrastructure and demographic pressures that exacerbate food insecurity. In order to addr...Burundi faces major agricultural constraints, including land fragmentation, soil erosion, limited access to inputs, inadequate infrastructure and demographic pressures that exacerbate food insecurity. In order to address the multiple challenges faced by farmers in rural areas, a study on improving agricultural productivity and food security in Burundi through optimized land use and diversified farming practices in agroforestry systems has been carried out. The study area is the communes of Giheta and Rutegama, all located in Burundi’s humid plateau livelihood zone, and involved 164 households grouped in coffee growing cooperatives supervised by the cooperative consortium COCOCA. The study uses a mathematical programming model to determine optimal crop selection based on factors such as production costs, yields and market demand. The findings of the study revealed significant insights into the demographic and socio-economic characteristics of the sampled population. Notably, 98.8% of respondents were engaged in agriculture, confirming the predominantly agricultural nature of Burundi. The results indicated that maize is the most important crop, occupying 33.9% of the average total cultivated area, followed by cassava at 26.5% and bananas at 19.4%. Together, these three crops accounted for a substantial portion of the total cultivated area, highlighting their significance in local agriculture. Beans and potatoes also play a role, occupying 14.4% and smaller areas, respectively. In terms of profitability, the study provides a detailed analysis of profit margins by crop. Bananas emerges as the most profitable crop, with a profit margin of 97.3%, followed closely by cassava at 96.1% and rice at 90.5%. These crops not only offered substantial yields relative to their production costs but also benefited from strong market demand. Other crops, such as beans (71.3%), coffee (70.3%), and vegetables (54.5%), also demonstrated considerable profitability, although they occupied smaller cultivated areas. Conversely, crops like pigeon peas (4.1%), potatoes (7.6%), and sweet potatoes (7.6%) exhibited the lowest profit margins, which may discourage farmers from investing in them unless other incentives, such as ecological benefits or local consumption needs, are present. Regarding the results, we therefore recommend to promote policies supporting agroforestry, improve market access and develop infrastructure to exploit these benefits.展开更多
Background: Social determinants of health (SDOH) significantly influence diseases with environmental components, like vector-borne parasitic diseases. This study aims to examine how these factors influence vector-born...Background: Social determinants of health (SDOH) significantly influence diseases with environmental components, like vector-borne parasitic diseases. This study aims to examine how these factors influence vector-borne parasitic diseases (VBPDs) transmission in Chad and provide recommendations for policy improvements. Methods: The study adopts the WHO Conceptual Framework of SDOH to compare two regions in Southern Chad: Kouh-Est, which has an ongoing vector control program, and Grand-Sido, which lacks such a program. The study includes both nomadic and sedentary populations to provide a comprehensive understanding of the SDOH influencing VBPDs. Households were randomly selected. Data on sociodemographic characteristics, literacy, knowledge of VBPDs and protective measures, and access to education and health facilities were collected. Results: A total of 202 households from 17 villages, including 820 participants, were surveyed. Agriculture, livestock, and fishing were the main occupations, involving 84.1% of participants. Literacy was low, with 36.7% non-educated, 47.7% completing primary school, 14.5% secondary school, and only 0.3% reaching tertiary education. Most villages lacked schools beyond the primary level, and nomadic populations were significantly less educated than sedentary ones (p Conclusion: Educational deficiencies, lack of protective measures against vectors, inadequate healthcare resources, and lifestyle conditions aggravated by poor road infrastructure, limited transportation, and economic constraints contribute to worsened VBPDs outcomes in these rural populations. Addressing these systemic issues in the surveyed communities is essential for improving health equity and VBPDs outcomes in these regions specifically and in similar populations settings more broadly.展开更多
Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and...Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and environmental factors influencing its distribution in the semi-arid Karamoja sub-region, Uganda. We surveyed 388 plots (5 m radius) at different altitudes, recording life stages, stem diameters, and regeneration patterns, and analyzed soil samples. Multivariate analyses, including Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA), Non-metric Multidimensional Scaling (NMDS), and Multiple Regression Modeling (MRM), identified key environmental factors affecting its distribution. Findings show that O. lanceolata populations in Moroto, Nakapiripirit, and Amudat districts are severely degraded due to overexploitation. The species is primarily regenerating through coppicing rather than seedlings, with an exploitation intensity of 56.6%. Population densities are low, distribution is irregular, and sustainable harvesting is not viable. Soil properties, particularly Ca2+, N, P, K+, Na+, and organic matter, significantly influence its abundance. Conservation efforts should focus on identifying suitable provenances for genetic preservation and plantation establishment. Areas with at least 9 trees per hectare in Moroto, Nakapiripirit, and Amudat could serve as potential sites for ex-situ plantations. Further research should explore how biotic interactions, genetic diversity, and morphology affect oil yield and quality to support restoration, breeding, and domestication initiatives.展开更多
文摘The conversion of forest land to other types of land cover is one of the major issues in the global fight against climate change. Understanding the direct and indirect factors of these conversions from local studies in the tropics is essential to project the future impact of human activities on the preservation of tropical forests in general and the forests of the Republic of Congo in particular. This study, conducted in five localities with different socioeconomic contexts in the Republic of Congo, aims to analyze the variability of drivers of deforestation and forest degradation linked to urbanization in the Congo Basin. Using a series of land cover maps from the years 1986, 2003 and 2019 for the cities of Ouesso, Pokola, Ngombe, Impfondo and Dongou, as well as field data and socio-economic information collected from local and central administrations, a unique model has been developed to understand the explanatory patterns of forest loss. Deforestation around urban centers is mainly due to urban agriculture due to population growth, as well as the spatial expansion of cities, which have a major impact on the stability and integrity of forests. Shifting agriculture is the main direct cause of deforestation and forest degradation, representing 48% of the total sample, followed by the collection of wood fuel (22%), the collection of construction wood (19%), illegal logging (6%) and urban expansion (5%). Forecasts indicate that forest loss around major cities will increase by 487, 20 ha to 5266, 73 ha by 2050 compared to the base year of 2019. This study highlights the need for a new system of land management and poverty alleviation of local populations to ensure the stability of the Congo Basin tropical forests around large and small African cities.
文摘One of the most promising vector control strategies for controlling dengue fever is the stable introduction of the obligate intracellular Wolbachia bacteria strain into Aedes aegypti mosquitoes. This method reduces the mosquito’s ability to transmit dengue through reproductive strategies associated with Wolbachia infection, such as parthenogenesis, male elimination or feminization, sex ratio distortions and cytoplasmic incompatibility. Expert knowledge and a risk assessment framework were used to identify the risks associated with the release of Wolbachia-bearing mosquitoes. Then, consultations with individual participants were organized and a Bayesian network (BN) was developed to capture the relationship between the hazards as well as the likelihood of these adverse events occurring. Finally, risk was calculated from the probability and consequence estimates obtained from our Burkina Faso participants, using a questionnaire based on the identified risks. Our “Cause More Harm” study yielded 46.15% negligible risk, 44.23% very low risk and 9.62% low risk. The “socio-cultural change” parameter had the greatest influence, with the perception that the dissemination project would be poorly received by the local population. This parameter alone accounted for 80% of the most significant risks. This explains the fact that hazard RA 49 “negative messages in social media” is ranked as the highest individual risk (although the risk is low) with a calculated risk of 0.261. The risk assessment was designed to integrate the interdependent complexity of hazards likely to affect the dissemination of technology in the environment. It represents an important implementation phase in the success of this innovative research, introducing a new technology to combat the transmission of dengue fever.
文摘In Burkina Faso, recent dengue outbreaks were exacerbated by Aedes aegypti mosquitoes, which have developed resistance to conventional insecticides. This study investigates the potential of Metarhizium pingshaense Met_S26, a fungus from Burkina Faso, for controlling both endophilic and exophilic Aedes mosquitoes. Traditional interventions are less effective against mosquitoes resting outdoors, and the ability of the fungus to be sexually transmitted could enhance its efficacy. Aedes mosquitoes were reared and exposed to various concentrations of Metarhizium pingshaense to assess its virulence. The fungus showed significant efficacy, with lethal times (LT80) ranging from 8.67 to 11.83 days depending on the concentration. Furthermore, bioassays demonstrated effective sexual auto-dissemination, with substantial transmission of fungal spores between infected and uninfected mosquitoes, leading to lower survival rates in uninfected mates. This study highlights Metarhizium pingshaense Met_S26 as a promising tool for controlling both indoor and outdoor Aedes populations, complementing existing vector control strategies such as the Sterile Insect Technique (SIT) and Wolbachia-based approaches. Future research should explore integrating this fungus with other control methods for a comprehensive vector management strategy.
文摘Solar stills represent a promising solution for desalinating saline waters, providing a sustainable alternative in regions with limited access to drinking water. This study evaluates the reliability of a two-dimensional (2D) numerical model of a solar still, developed using COMSOL® Multiphysics software, focusing on a passive cascading device called “Pano Rano.” Two physical prototypes were constructed: one with a standard concrete basin and the other with acrylic plastic. The simulations revealed significant differences in theoretical yield based on the material used. With a radiation of 1200 W/m2, the acrylic prototype displayed an evaporation of 4455.53 mL/m2 and a production of 2925.98 mL/m2 of distilled water, while the concrete model showed an evaporation of 2109.95 mL/m2 and produced 1383.93 mL/m2 of distilled water. The results indicate that evaporation significantly exceeds condensation, highlighting an underutilized evaporation potential. The evaluation of the numerical model’s performance against experimental results was conducted using the mean squared error (MSE) and the coefficient of determination (R2). The best performance was observed in summer (MSE of 16.24;R2 of 0.95), while winter results were less convincing (MSE of 204.77;R2 of −2.78). This variability underscores the model’s limitations and the need for future research. The study also demonstrates that the choice of basin material significantly influences productivity, with acrylic plastic outperforming concrete in terms of thermal efficiency.
文摘The pervasive use of photo editing applications such as Photoshop and FaceTune has significantly altered societal beauty standards, particularly for individuals with skin of color, often leading to unrealistic expectations regarding skin appearance and health. These tools allow users to smooth skin textures, lighten skin tones, and erase imperfections, perpetuating Eurocentric beauty ideals that frequently marginalize the natural diversity of skin tones and textures. Consequently, individuals with skin of color may seek dermatological interventions—such as skin lightening treatments, aggressive acne scar revisions, and other cosmetic procedures—aimed at achieving appearances that align more closely with digitally manipulated images. This pursuit of an unattainable aesthetic can result in increased dissatisfaction with common skin conditions like hyperpigmentation and keloids, which are often misrepresented in edited photos. Additionally, the psychological impact of these alterations can exacerbate feelings of inadequacy, contributing to conditions such as anxiety and body dysmorphic disorder. Dermatologists face the dual challenge of addressing patients’ clinical needs while also managing their expectations shaped by digital enhancements. To combat this, it is essential for dermatologists to integrate patient education that emphasizes the beauty of diverse skin tones and the discrepancies between digital images and authentic skin health. By fostering an understanding of realistic outcomes and promoting the acceptance of natural skin characteristics, dermatologists can empower individuals with skin of color to prioritize authentic skin health over digitally influenced ideals, ultimately leading to more satisfying dermatological care and improved self-image.
文摘Background: Malnutrition, a serious public health concern, is influenced by various factors. Objective: The study aims to explore malnutrition issues among infants under five years old in Guéra Province. Methods: The study used a cross-sectional design and a two-stage cluster sampling method to select participants. The study population was infants aged between 0 - 24 months. Data collection was done between June 2023 and September 2024;it included anthropometric measurements, blood analyses, and interviews. Anthropometric parameters were calculated using ENA for SMART software. Statistical analyses were performed by R Studio to investigate associations between different characteristics, using logistic regression models to identify risk factors. A p-value less than 0.05 was considered significant. Results: The study included 377 infants in eight villages in Guéra Province, Chad. The sample was predominantly girls (55.3%), with a median age of 16 months. Most infants (94%) were mixed-fed, and only 6% were exclusively breastfed. We found that 7.3% of children were globally malnourished, with higher rates in boys 9.6%. A significant disparity existed between boys and girls in global acute malnutrition (GAM) rates, with boys having a higher prevalence of 17.9%. A substantial proportion of Infants were underweight, with males 27.4%. Stunting was prevalent 20.1%. Several factors were associated with malnutrition, including gender, feeding practices, infectious diseases, and socioeconomic factors. Diarrhea, malaria, limited access to drinking water, and early diet diversification were significantly associated with malnutrition. Conclusion: Targeted interventions are necessary to address these issues and improve the nutritional status of children in the Guéra province.
基金Supported by the Henan Province Key Research and Development Project(231111211300)the Central Government of Henan Province Guides Local Science and Technology Development Funds(Z20231811005)+2 种基金Henan Province Key Research and Development Project(231111110100)Henan Provincial Outstanding Foreign Scientist Studio(GZS2024006)Henan Provincial Joint Fund for Scientific and Technological Research and Development Plan(Application and Overcoming Technical Barriers)(242103810028)。
文摘The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method for infrared and visible image fusion is proposed.The encoder designed according to the optimization objective consists of a base encoder and a detail encoder,which is used to extract low-frequency and high-frequency information from the image.This extraction may lead to some information not being captured,so a compensation encoder is proposed to supplement the missing information.Multi-scale decomposition is also employed to extract image features more comprehensively.The decoder combines low-frequency,high-frequency and supplementary information to obtain multi-scale features.Subsequently,the attention strategy and fusion module are introduced to perform multi-scale fusion for image reconstruction.Experimental results on three datasets show that the fused images generated by this network effectively retain salient targets while being more consistent with human visual perception.
文摘Introduction: Influenza A (Flu A) and B (Flu B) viruses are responsible for severe acute respiratory infections (SARI) worldwide, with a morbidity of 5 million and mortality of 29,000 - 650,000 deaths per year. Influenza B viruses are an important cause of respiratory infections in humans, but they tend to be underappreciated due to the predominance of Influenza A. No molecular study on Influenza B has been carried out in the DRC. This study was conducted to document the molecular evolution of the hemagglutinin (HA) gene in the circulating Influenza B strains over the eight consecutive epidemic seasons (from 2015 to 2022). Methods: Samples were collected from outpatient cases suspected of influenza-like illness (ILI) and in all hospitalized patients with SARI from January 2015 to December 2022. Molecular analysis was done to determine influenza type and subtype, and then segments encoding the HA gene of Influenza B viruses were performed. Results: Of 8497 samples collected and tested, 639 (7.5%) were positive for influenza viruses, including 389 (60.8%) for Influenza A viruses and 248 (38,8%) for Influenza B viruses. Of the positive Influenza B samples, 91 were sequenced, including 26 belonging to the B/Yamagata lineage and 65 to the B/Victoria lineage. The HA gene of Influenza B viruses circulating in the DRC showed deletions in the HA1 region. Molecular analysis of Influenza B viruses reflects the genetic diversity of Influenza B/Yam virus clades (Y2, Y3, Y3V1A) alternating with Influenza B/Victoria virus clades (V1A, V1A.3) depending on the year and influenza seasons. The phylogenetic analysis of these Influenza B strains shows compatibility with the corresponding vaccine strains that the WHO had validated for each influenza season. Conclusion: This study underscores the importance of continuous molecular surveillance of Influenza B viruses in the DRC to understand their epidemiology and evolutionary dynamics. Identifying mutations, such as HA deletions, is critical for assessing their impact on transmissibility vaccine efficacy and guiding effective vaccination and control strategies.
文摘This study examines hemodynamic behavior in particular cases of pulmonary hypertension without treatment. Pulmonary hypertension represents an anomalous hemodynamic state and is characterized by an excessively high blood pressure in the pulmonary artery. To simulate the hemodynamic abnormalities in pulmonary hypertension under different causes and pathologies, we construct a localized parameter circuit model governed by nonlinear ordinary derivative equations of the human circulatory system. Thus, two special cases are considered, namely pulmonary the artery stenosis and the left ventricular diastolic dysfunction. For each case of pulmonary hypertension development, we determine the relationships between blood pressure and chamber and vessel pressure-volume. When the pulmonary hypertension is due to pulmonary artery stenosis, it appears that the right ventricular pressure increases up to 90 mm Hg, likewise the rise in pulmonary artery resistance induces direct increment in pulmonary artery pressure. However, when the pulmonary hypertension is due to left ventricular diastolic dysfunction, we note that the left atrial pressure and the pulmonary vein pressure augment, leading to the growth of the pulmonary artery blood pressure. The established results within this paper are useful for understanding the hemodynamic mechanism of particular pulmonary hypertension.
文摘Background: Riedel’s thyroiditis is a rare form of chronic inflammatory disease affecting the thyroid gland. It is characterised by the replacement of the thyroid parenchyma by fibrous tissue. It also affects the adjacent vital structures. Due to its characteristic presentations, Riedel’s thyroiditis may not be immediately diagnosed. Objectives: Through this clinical case, we aimed to describe the pathology and clinical characteristics of Riedel’s thyroiditis and the diagnostic, therapeutic, and progressive modalities. Methods: A 62-year-old woman with no particular pathological history is consulted at the outpatient clinic for anterior cervical swelling that has been present for more than 5 years and is associated with respiratory discomfort and dysphagia to solids. Clinical examination, ultrasound, lab tests and injected cervical computed tomography (CT) were performed. These tests were completed with pathological examination. Results: General conditions were normal. Anterior cervical swelling, marked on the right, of hard consistency, causing cervical shielding with healthy surrounding skin, was observed at the examination. A compressive goitre was first suspected. Thyroid tests showed hypothyroidism. The CT revealed a hypodense goitre with micro-calcifications developed at the expense of the right lobe and exerting a mass effect on the trachea and oesophagus. Aspiration thyroid was not conclusive given the suspicion of the malignant nature of the goitre, and the decision to perform a right loboisthmectomy was taken. Pathological examination of the biopsy showed atrophy of the thyroid parenchyma with dense septal fibrosis punctuated by lymphocytes and extending throughout the tissue associated with inflammation—an appearance in favour of Riedel’s thyroiditis. The patient was treated with Levothyroxine and corticoids. Conclusions: This case points out the challenges in diagnosing Riedel’s Thyroiditis and the complexity of the pathology that requires a rigorous diagnostic approach and appropriate treatment for the best outcome.
文摘Introduction: Arbovirus diseases such as dengue and chikungunya threaten public health worldwide. Early and rapid diagnosis and surveillance of dengue virus (DENV) and chikungunya virus (CHIKV) infections are essential to the control of these diseases. In this study, we evaluate the diagnostic performance of our new in-house multiplex RT-qPCR method for detecting DENV serotypes and CHIKV in an external laboratory. Methodology: The evaluation study was conducted on 200 clinical samples of suspected patients for arbovirus disease infection, collected in Centre de Recherche Biomoléculaire Pietro Annigoni (CERBA), Ouagadougou, Burkina Faso. Our new multiplex RT-qPCR was compared to the commercial kit, the Zika, Dengue, and Chikungunya (ZDC) Real-Time PCR Assays kit (Bio-Rad, California, USA). Results and Conclusions: Among 200 samples, 21.5% (43/200) were DENV-positive by multiplex RT-qPCR, and 21.5% (43/200) were also DENV-positive by reference real-time RT-PCR. 157 (78.5%) samples tested negative for DENV by both tests (new mRT-qPCR and reference test). The sensitivity and specificity of mRT-qPCR were 100%. The DENV serotypes detected were DENV-1 60.5% (26/43) and DENV-3 39.5% (17/43). CHIKV was not detected in this study. Our new mRT-qPCR is sensitive, cost-effective, simple, and can be used in developing country laboratories.
文摘One of the main objectives of artificial intelligence lies in the simulation of the behavior of living organisms;emotions are a fundamental part of life, and they cannot be left aside when simulating behavior. In this research, software is developed that simulates the behavior of birds with different characteristics. The latter interacts by considering different stimuli from the environment (external), and the internal state of the subject (objectives). To achieve this, a model of birds in the role of prey and predators is developed that focuses on the study of the interaction between these organisms that exhibit specific behaviors in their environment. This project is a seminal work that aims to represent the emotions of birds, and the latter caused by stimuli from a dynamic environment.
文摘This study develops an analytical model to evaluate the cooling performance of a porous terracotta tubular direct evaporative heat and mass exchanger. By combining energy and mass balance equations with heat and mass transfer coefficients and air psychrometric correlations, the model provides insights into the impact of design and operational parameters on the exchanger cooling performance. Validated against an established numerical model, it accurately simulates cooling behavior with a Root Mean Square Deviation of 0.43 - 1.18˚C under varying inlet air conditions. The results show that tube geometry, including equivalent diameter, flatness ratio, and length significantly influences cooling outcomes. Smaller diameters enhance wet-bulb effectiveness but reduce cooling capacity, while increased flatness and length improve both. For example, extending the flatness ratio of a 15 mm diameter, 0.6 m long tube from 1 (circular) to 4 raises the exchange surface area from 0.028 to 0.037 m2, increasing wet-bulb effectiveness from 60% to 71%. Recommended diameters range from 5 mm for tubes under 0.5 m to 1 cm for tubes 0.5 to 1 m in length. Optimal air velocities depend on tube length: 1 m/s for tubes under 0.8 m, 1.5 m/s for lengths of 0.8 to 1.2 m, and up to 2 m/s for longer tubes. This model offers a practical alternative to complex numerical and CFD methods, with potential applications in cooling tower optimization for thermal and nuclear power plants and geothermal heat exchangers.
文摘This work aims at the mathematical modeling of a parabolic trough concentrator, the numerical resolution of the resulting equation, as well as the simulation of the heat transfer fluid heating process. To do this, a thermal balance was established for the heat transfer fluid, the absorber and the glass. This allowed us to establish an equation system whose resolution was done by the finite difference method. Then, a computer program was developed to simulate the temperatures of the heat transfer fluid, the absorber tube and the glass as a function of time and space. The numerical resolution made it possible to obtain the temperatures of the heat transfer fluid, the absorber and the glass. The simulation of the fluid heating process was done in one-hour time steps, from six in the morning to six in the afternoon. The results obtained show that the temperature difference between the inlet and the outlet of the sensor is very significant. These results obtained, regarding the variation of the temperatures of the heat transfer fluid, the absorber and the glass, as well as the powers and efficiency of the parabolic trough concentrator and various factors, allow for the improvement of the performances of our prototype.
文摘The iTrace Dysfunctional Lens Index (DLI) offers a quantitative approach to lens assessment, potentially facilitating the early detection of cataracts. Globally, the prevalence of cataracts has increased due to aging populations, and in Morocco, they remain a significant cause of reversible blindness. This study examines the specificity and sensitivity of the DLI in identifying cataracts among a large sample of patients, focusing on differentiating early-stage cataracts from other conditions that affect visual quality. The DLI, which generates a score from 0 to 10, provides an objective lens quality measure, with lower values indicating dysfunction. In a cohort of 621 patients (1242 eyes), 243 eyes displayed a DLI < 5. Of these, 56 eyes had confirmed cataracts and 187 eyes presented with various ocular conditions but clear lenses. The results demonstrate 100% sensitivity for identifying cataracts within the DLI < 5 threshold, with a specificity of 72.4%. These findings highlight the utility of DLI as a diagnostic tool for early-stage cataracts despite variability influenced by ocular characteristics such as axial length and keratoconus.
文摘Objective: Pregnancy in a scarred uterus is considered to be high-risk, especially during parturition. Nevertheless, the literature favours vaginal delivery as long as obstetric conditions are favourable. The aim of our study was to contribute to the improvement of delivery management for women with scar uteri at the CHU Communautaire. Methodology: This was a cross-sectional study conducted over an 18-month period from 01 January 2020 to 30 June 2021 on women with scar uterus who came to give birth at the CHU Communautaire maternity unit. The sample was exhaustive;any parturient with a history of scarred uterus of more than one year with a clinically normal pelvis and whose fetus was in cephalic presentation. The following were excluded from the study: pregnant women with a uterine scar of less than one year, fetuses in a non-cephalic vertex presentation, pregnant women with antecedent complicated childbirth at the previous cesarean section, large fetuses informed consent had been obtained from the pregnant women. Anomynia was respected throughout the study. Results: During this period, we recorded 205 parturients with a scar uterus. The incidence of delivery with a scar uterus was 9.5%. Uterine testing was attempted in 85.9% of cases, with a success rate of 75.6%. Factors predictive of a successful uterine test was: maternal age less than 35 years (P = 0.0027), entry into labour at the reference maternity hospital (P Conclusion: Delivery with a scarred uterus is an increasingly frequent occurrence at the Maternity Unit of the CHU Communautaire in Bangui. Uterine testing is the first option if conditions allow, but careful selection of candidates during antenatal care or at the very beginning of labour is necessary for this type of delivery.
文摘Burundi faces major agricultural constraints, including land fragmentation, soil erosion, limited access to inputs, inadequate infrastructure and demographic pressures that exacerbate food insecurity. In order to address the multiple challenges faced by farmers in rural areas, a study on improving agricultural productivity and food security in Burundi through optimized land use and diversified farming practices in agroforestry systems has been carried out. The study area is the communes of Giheta and Rutegama, all located in Burundi’s humid plateau livelihood zone, and involved 164 households grouped in coffee growing cooperatives supervised by the cooperative consortium COCOCA. The study uses a mathematical programming model to determine optimal crop selection based on factors such as production costs, yields and market demand. The findings of the study revealed significant insights into the demographic and socio-economic characteristics of the sampled population. Notably, 98.8% of respondents were engaged in agriculture, confirming the predominantly agricultural nature of Burundi. The results indicated that maize is the most important crop, occupying 33.9% of the average total cultivated area, followed by cassava at 26.5% and bananas at 19.4%. Together, these three crops accounted for a substantial portion of the total cultivated area, highlighting their significance in local agriculture. Beans and potatoes also play a role, occupying 14.4% and smaller areas, respectively. In terms of profitability, the study provides a detailed analysis of profit margins by crop. Bananas emerges as the most profitable crop, with a profit margin of 97.3%, followed closely by cassava at 96.1% and rice at 90.5%. These crops not only offered substantial yields relative to their production costs but also benefited from strong market demand. Other crops, such as beans (71.3%), coffee (70.3%), and vegetables (54.5%), also demonstrated considerable profitability, although they occupied smaller cultivated areas. Conversely, crops like pigeon peas (4.1%), potatoes (7.6%), and sweet potatoes (7.6%) exhibited the lowest profit margins, which may discourage farmers from investing in them unless other incentives, such as ecological benefits or local consumption needs, are present. Regarding the results, we therefore recommend to promote policies supporting agroforestry, improve market access and develop infrastructure to exploit these benefits.
文摘Background: Social determinants of health (SDOH) significantly influence diseases with environmental components, like vector-borne parasitic diseases. This study aims to examine how these factors influence vector-borne parasitic diseases (VBPDs) transmission in Chad and provide recommendations for policy improvements. Methods: The study adopts the WHO Conceptual Framework of SDOH to compare two regions in Southern Chad: Kouh-Est, which has an ongoing vector control program, and Grand-Sido, which lacks such a program. The study includes both nomadic and sedentary populations to provide a comprehensive understanding of the SDOH influencing VBPDs. Households were randomly selected. Data on sociodemographic characteristics, literacy, knowledge of VBPDs and protective measures, and access to education and health facilities were collected. Results: A total of 202 households from 17 villages, including 820 participants, were surveyed. Agriculture, livestock, and fishing were the main occupations, involving 84.1% of participants. Literacy was low, with 36.7% non-educated, 47.7% completing primary school, 14.5% secondary school, and only 0.3% reaching tertiary education. Most villages lacked schools beyond the primary level, and nomadic populations were significantly less educated than sedentary ones (p Conclusion: Educational deficiencies, lack of protective measures against vectors, inadequate healthcare resources, and lifestyle conditions aggravated by poor road infrastructure, limited transportation, and economic constraints contribute to worsened VBPDs outcomes in these rural populations. Addressing these systemic issues in the surveyed communities is essential for improving health equity and VBPDs outcomes in these regions specifically and in similar populations settings more broadly.
文摘Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and environmental factors influencing its distribution in the semi-arid Karamoja sub-region, Uganda. We surveyed 388 plots (5 m radius) at different altitudes, recording life stages, stem diameters, and regeneration patterns, and analyzed soil samples. Multivariate analyses, including Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA), Non-metric Multidimensional Scaling (NMDS), and Multiple Regression Modeling (MRM), identified key environmental factors affecting its distribution. Findings show that O. lanceolata populations in Moroto, Nakapiripirit, and Amudat districts are severely degraded due to overexploitation. The species is primarily regenerating through coppicing rather than seedlings, with an exploitation intensity of 56.6%. Population densities are low, distribution is irregular, and sustainable harvesting is not viable. Soil properties, particularly Ca2+, N, P, K+, Na+, and organic matter, significantly influence its abundance. Conservation efforts should focus on identifying suitable provenances for genetic preservation and plantation establishment. Areas with at least 9 trees per hectare in Moroto, Nakapiripirit, and Amudat could serve as potential sites for ex-situ plantations. Further research should explore how biotic interactions, genetic diversity, and morphology affect oil yield and quality to support restoration, breeding, and domestication initiatives.
