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Influence of Prandtl Number on Thin Film Condensation in Forced Convection in an Inclined Wall Covered with a Porous Material

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Advances in Materials Physics and Chemistry 2022年第6期12卷 125-140页

作者： Goumbo ndiaye Momath ndiaye Vincent Sambou pape tamsir ndiaye Madialène Sène Cheikh Mbow The Water Energy Environment and Industrial Processes Laboratory of the Polytech Higher School Cheikh Anta Diop University Dakar Senegal Laboratory of Fluids Mechanics and Transfers Faculty of Sciences and Technologies Cheikh Anta Diop University Dakar Senegal Department of the Ufr Hydraulics Rural Engineering Machinery and Renewable Energy University of Sine Saloum Elhadji Ibrahima NIASS Kaolack Senegal

The numerical study of thin film type condensation in forced convection of a saturated pure vapor in an inclined wall covered with a porous material is presented. The generalized Darcy-Brinkman-Forchheimer (DBF) model is used to describe the flow in the porous medium while the classical boundary layer equations have been exploited in the case of a pure liquid. The dimensionless equations are solved by an implicit finite difference method and the iterative Gauss-Seidel method. The objective of this study is to examine the influence of the Prandtl number on the hydrodynamic and thermal fields but also on the local Nusselt number and on the boundary layer thickness. For Pr ≤ 0.7 (low) the velocity and the longitudinal temperature increase with the Prandtl number. On the other hand, when Pr ≥ 2 (high) the Prandtl number no longer influences the velocity and the longitudinal temperature. The local Nusselt number increases as the Prandtl number increases and the thickness of the hydrodynamic boundary layer increases as the Prandtl number decreases.

关键词： Condensation Thin Film Forced Convection Inclined Porous Wall Generalized Darcy-Brinkman-Forchheimer Model Prandtl Number

Physical and Thermo-Mechanical Properties of Composite Materials Based on Raw Earth and Crushed Palm Leaf Fibers (Borassus aethiopum)

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Materials Sciences and Applications 2024年第9期15卷 358-377页

作者： Mouhamadou Nabi Kane Mapathe ndiaye pape Moussa Touré Adama Dione University College of Architecture of Dakar (CUAD) UFR SI University of Thies This Senegal Laboratory of Mechanics and Modeling UFR SI University of This This Senegal Laboratoire dEnergtique Applique (LEA) Cheikh Anta Diop University Dakar Senegal Institut of Earth Sciences (IST) Universit Cheikh Anta Diop (UCAD) Dakar Senegal

The objective of this study is to seek solutions to reduce the impact of buildings on climate change and to promote the use of local bio-sourced or geo-sourced materials for sustainable construction. Different samples of raw earth from 3 sites were taken in the commune of Mlomp. Geotechnical tests showed that the raw earth samples from sites 2 and 3 have more clay fraction while site 1 contains more sand. The fact of integrating fibers from crushed palm leaves (Borassus aethiopum) (2%, 4% and 6%) into the 3 raw earth samples reduced the mechanical resistance to compression and traction of the 3 raw earths. The experimental results of thermal tests on samples of earth mixtures with crushed Palma leaf fibers show a decrease in thermal conductivity as well as thermal effusivity as the percentages increase (2%, 4% and 6%) of fibers in raw earth for the 3 sites. This shows that this renewable composite material can help improve the thermal insulation of building envelopes.

关键词： Raw Earth Palma Leaf Fibers Ecological Composite Materials Physical Thermo-Mechanical Thermal Conductivity Thermal Effusivity

Perception of Beneficiaries and Stakeholders about the Services Offered by Health Huts Put in Place by the Health Project—Community Health of USAID in the Goudomp Health District (Senegal)

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Health 2015年第9期7卷 1075-1080页

作者： Alioune Badara Tall pape Gallo Sow Abdoul Aziz ndiaye Ousseynou Ka Université Alioune Diop de Bambey Bambey Senegal

The Health Project—Community Health USAID is a community-based intervention that has been implemented by a group of NGOs, among which there is Africare, for a period of 5 years (2006-2011). It seeks to strengthen the community health system through a package of basic services offered at the health center, and as well as to improve the skills and knowledge of community actors. The main objective of this study is to capture the perceptions of beneficiaries and stakeholders about the services offered at the PSSC health posts located in the health district Goudomp. A qualitative cross-sectional study on the perception of the community of the USAID PSSC and quality of services offered by the health huts was conducted from the 2nd to 5th of May 2009 in the Goudomp health district. To achieve the objectives of this study, we conducted focus group discussions with all the community leaders and had individual interviews with the community health workers (CHWs) and the supervisor of the NGO Africare. From most of the discussions, it can be concluded that the activities of the health hut are not well known by the populations. The best known activities are those performed by the nurse: immunization and prenatal care. The existence of health huts at the community level was considered beneficial by all the community leaders. For the majority of the participants to the focus group discussions, the health huts “provided access to basic care”. Some participants, however, pointed out the “frequent drugs shortages” which, according to them, would explain the low attendance of the health huts in favor of the health post. The majority of CHWs and matrons felt that supervision activities were done on a regular basis. During the interviews, they mentioned many difficulties. However, the most common problem is the fact that the CHWs and the matron “who have no other source of income” were not salaried workers. This assessment has identified some difficulties in the implementation of the PS

关键词： Perception Community Health Health Huts USAID Goudomp

Phylogenetic Relationship and Molecular Divergence Dating Using SRY Gene Polymorphism about Four Ladoum Sheep Lineages in Senegal

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Open Journal of Animal Sciences 2023年第2期13卷 179-198页

作者： pape Madiop Sembène Fatimata Mbaye Mama Racky ndiaye Mbacké Sembène Genomic Laboratory Department of Animal Biology Cheikh Anta Diop University Dakar Senegal

Animal genetic resources are playing a vital role in livestock production and are essential to food security. The present study aims to contribute to a better understanding genetic local sheep breeds and to elucidate the phylogenetic relationships through the evolution of the SRY gene in four different lineages of Ladoum sheep raised in Senegal. After a brief analysis of genetic diversity, the phylogenetic relationships and molecular dating were inferred through haplotype networks and four phylogenetic reconstruction methods. The different haplotype networks are constructed with NETWORK ver. 5.***.0.0 using the Median-Joining method. Phylogenetic trees were reconstructed using neighbor-joining, maximum parsimony, maximum likelihood and Bayesian inference. The robustness of the nodes in phylogenetic trees of the three first methods was assessed by 1000 bootstraps. For Bayesian inference, the posterior probability distribution of the trees was estimated by 4 MCMC chains. 5,000,000 generations were performed for each of the chains by sampling the different parameters every 1000 generations. Results show a low polymorphism. Haplotypic diversity is much higher than the average nucleotide divergence between all pairs of haplotypes. The majority and central haplotype indicates a close relationship between “Batling” and “Tyson” individuals. “Birahim” lineage is very distinct from the rest. Phylogenetic trees confirm two genetically separate clades between “Birahim” and the other lineages. The period of divergence between “Birahim” lineage versus the common ancestor of the other three lineages was 2504 years ago. The polyphyly revealed in “Birahim” lindicates that this lineage does not contain the common ancestor of all individuals who compose it. It could therefore be derived from two or more sheep breeds with a common ancestor, Ovis aries. The monophyletic clade appears to be a group including a common ancestor and all of its genetic descendants. This group, bringing togethe

关键词： Genetic Diversity Phylogenetic Relationship Molecular Dating SRY Gene Sheeps Ladoum Senegal

Effects of protein and mineral supplementation on the performance of lactating dairy cows gobra and crossbreed guzerat during the dry season in senegal

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Open Journal of Animal Sciences 2014年第1期4卷 18-22页

作者： Fat Cheikh Ndione Emile Codjo Agbangba Ousmane ndiaye Idrissa Sane Abdou Diouf Amadou tamsir Diop Centre de Recherches Zootechniques de Dahra Institut Sénégalais de Recherches Agricoles Dahra Sénégal Département de Biologie Végétale Université Cheikh Anta Diop Dakar Sénégal Laboratoire national D’élevage et de Recherche Vétérinaire (LNERV) Institut Sénégalais de Recherches Agricoles Dakar Sénégal

The purpose of this study carried out in the township of Dahra was to access the effect of dry season protein and mineral supplementation of Gobra and Crossbreed Guzerat cows on milk production. The experimental design is a completely randomized block. The treatments were: supplement of molasse-urea blocks with supplement of hay;supplement of molasse-urea blocks without any hay;no supplement of molasse-urea blocks and supplement of hay;no supplement of molasse-urea block without any hay. For each breed, the treatments were replicated three times on a lot of cows with the similar zootechnic parameters. A total of twelve lactating cows per breed were then used. The supplement of block + hay has significantly (p < 5%) allowed obtaining the largest average daily quantity of milk: 1.9 ± 0.7L/day/cow and 2.4 ± 0.8 L/day/cow respectively in Gobra and Crossbreed Gobra*Guzerat. The increases in production compared to the control treatment (without supplement) are 52.63% and 100% respectively in the breed Gobra and Gobra*Guzerat. The supplement of hay comes in the second place and contributes to an additional production of 66.66% in both breeds of cow. Then, the supplement of block follows and it allows increasing the production of 44.44% and 50% respectively in Gobra and Crossbreed. In both races, the supplement of block + hay has allowed obtaining the highest profits of $1.6/L/day/cow for Gobra and $ 2.8/L/day/cow for the Crossbreed, that equals to an increase by $ 0.3 and $ 0.9 compared to the control treatment. The supplement of hay and the block supplement have respectively given a profit of 0.4 and $ 0.3/L/day/cow in Gobra and 0.6 and $ 0.4/L/day/cow in the Crossbreed. The adoption of supplementation molasse-urea block + hay by producers appears an alternative to boost milk production in dry season.

关键词： Milk Yield Supplements Gobra Guzerat Dry Season

Hierarchy of Rural Localities in the Niakhar Area (Fatick, Senegal)

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Journal of Geographic Information System 2022年第3期14卷 221-239页

作者： Alphousseyni Ndonky Mouhamadou Moustapha Mbacké Ndour Ibrahima ndiaye Richard Lalou pape Boubou Sow Engineering Sciences Training and Research Unit University of Thies Thies Senegal School of Applied Economics Cheikh Anta Diop University Dakar Senegal MERIT_UMR 216/IRD Paris Descartes University Paris France

Although the study of the hierarchy of localities presents an important social and economic stake, studies focused on the hierarchy of rural localities are relatively weak, especially in Africa. It is important to highlight the hierarchy of rural areas in order to reveal poles that can support sustainable growth. Our main objective is to study the hierarchy of rural localities in the Niakhar area, using a geographic approach. The data come from the Niakhar demographic, epidemiological and environmental observatory database and the Niakhar Atlas project of the French Research Institute for Development (IRD). The net flow method, the primacy index, the median population threshold method and the measurement of the correlation between level of centrality and population size are used to analyze the data. Our study allowed us to determine the main types of centrality and to establish the hierarchy of rural localities in the Niakhar zone. It also highlighted the strong correlation between the rank of localities and the size of the population of the latter. The main contribution of our work is to have highlighted, in order, the structuring localities of the rural space of the Niakhar area, by combining several indicators of centrality.

关键词： Hierarchy Rural Localities Centrality Population Size Service Functions Attractiveness

Assessment of Radiofrequency in Otorhinolaryngology at the Military Hospital of Ouakam (MHO)

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International Journal of Otolaryngology and Head & Neck Surgery 2021年第5期10卷 433-440页

作者： Abdou Sy Ahmadou Cheikhou Sall Mamadou Oury Barry Ndè ye Fatou Thiam pape Yakhya Ba Malick ndiaye ENT Department Diamniadio Children Hospital Dakar Senegal ENT and Cervicofacial Surgery Department of the Military Hospital of Ouakam (MHO) Hyderabad India

Introduction: Coblation® is a low temperature-controlled tissue ablation technique widely used in human surgery. Its development in otorhinolaryngology has allowed a spectacular advance in the management of diseases of the nasal and oral cavities. The objective of our work was to study the indications for radiofrequency in ENT, to describe the technical aspects and to evaluate the results of his practice at the HMO. Patients and Methods: This is a retrospective study carried out in the ENT and Head and Neck Surgery department of the Ouakam Military Hospital (MHO) over a period of 3 years (from January 2015 to the end of December 2017), involving 37 patients who received radiofrequency treatment in the ENT sphere. Results: The study was carried out on 37 patients. The sex ratio of 0.19. The mean age of the patients was 33.3 years. The indications were dominated by chronic caseous cryptic tonsillitis with or without halitosis with 24 cases (64.9%) followed by recurrent tonsillitis in 5 cases (13.5%) then we have obstructive hypertrophy of the palatal tonsils with syndrome sleep apnea (OSAS) in 4 cases (10.8%) followed by nasal obstruction (hypertrophy of the inferior turbinates) and hypertrophy of the soft palate and uvula in 2 cases (5.4%). The complication rate was 8.1% and dominated by transient dysgeusia in 1 case or 2.7%, uvula edema in 1 case or 2.7% and bleeding in 1 case or 2.7%. The postoperative follow-up was done one week, 1 month, 3 months, 6 months and 12 months after radiofrequency. Volumetric reduction begins to set in from 1 month (62.5%) and becomes maximum in 3 months (74.3%). Conclusion: Coblation® is a controlled tissue ablation technique at low temperature, patented by ArthroCare® Corporation in 1997. Very widespread in human surgery. Its development in otorhinolaryngology was later, but allowed a spectacular advance in the management of diseases o

关键词： Radiofrequency Evaluation Coblation Indications Techniques Complication

Evaluation of the Knowledge of CT Scan Prescribers on Patients’ Radioprotection in Senegal

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Open Journal of Biophysics 2019年第3期9卷 204-217页

作者： Serigne Moussa Badiane pape Ibrahima Sane Coumba Ndoffene ndiaye Kalidou Gueye Oumar Ndoye Kuassi M. Amoussou-Guenou Mamadou Mbodji Biophysics and Nuclear Medicine Gaston Berger University Saint-Louis Senegal Biophysics and Nuclear Medicine Cheikh Anta DIOP University Dakar Senegal Biophysics and Nuclear Medicine Abomey-Clavi Benin University Benin

Medical imaging has enabled major improvements in the medical care of the patient. However, some of these tests have the disadvantage of using ionizing radiation at low doses. Although the CT scan is a powerful diagnostic tool, it remains a highly radiant imaging modality. In addition, the risk of radiation-induced cancer associated with low X-ray doses is established by the American Phase 2 study BEIR VII, and preventive measures require a good level of knowledge on radioprotection by imaging test prescribers. In our study, we evaluated the knowledge of CT scan prescribers in Senegal regarding patient radioprotection. These prescribers consisted of physicians and surgeons without distinction of specialty. Our objective was to have the required data for optimizing CT prescriptions in compliance with the principles of radioprotection. Our work focused on a descriptive analytical study of 107 doctors who prescribed CT scan in public health institutions in Senegal. Our results revealed poor knowledge of doctors prescribing CT scan on induced radio risks, even though the majority of them stated that they took those risks into account. Our data were not isolated, they were applicable to similar studies conducted outside Senegal. In summary, our study led on the one hand to recommendations on initial and continuing training and on the other hand on organizational and regulatory considerations.

关键词： Radioprotection Risk of Radiation-Induced Cancer CT Scan Prescribers Health Institutions in Senegal

Indications and Results of Repair of the Rhumatismal Valve in Children in Senegal concerning 63 Cases

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World Journal of Cardiovascular Surgery 2020年第5期10卷 51-58页

作者： Momar Sokhna Diop Papa Amath Diagne Ndeye Fatou Sow Papa Salmane Ba Magaye Gaye pape Ousmane Ba Souleymane Diatta Moussa Seck Diop Mareme Soda Mbaye pape Adama Dieng Amadou Gabriel Ciss Assane ndiaye Thoracic and Cardiovascular Surgery Center Cheikh Anta Diop University Dakar Sénégal

In Africa, acute rheumatic fever is endemic. Cardiac involvement is one of the most common complications in the form of valvular heart disease representing all damages to the heart valves. It is in this perspective that we realized this study whose general objective was to evaluate the results of mitral repair surgery in children in Senegal and the specific objective was to state the indications for mitral repair surgery and assess the results in terms of morbidity and mortality. This is a retrospective and analytical monocentric study, in the thoracic and cardiovascular surgery department of FANN National University Hospital Center in Dakar. It took place over a period of 30 months. All the patients who underwent mitral surgery, aged less than 18 years were included. The total number of patients was 63, including 39 girls and 24 boys, a sex ratio of 0.62. The average age at the time of the surgery was 12 years old [5 - 17]. The functional symptomatology was dominated by the dyspnea found in all the patients. Cardiac ultrasound was diagnosed with mitral regurgitation in all patients. For all surgical procedures, the approach was a vertical midline sternotomy. The mitral valve was approached by left atriotomy in 40 patients (63.5%) and by transseptal way in 23 patients. All patients had undergone mitral valve repair associated or not with either aortic valve repair in 9 patients (14.2%), aortic valve replacement in 3 patients (4.8%), or one tricuspid valve repair in 31 patients (49%). The average duration of intubation was 6 hours [2 - 52]. The average length of stay in intensive care was 2 days. Postoperative complications have been observed. Surgery was performed in 10 patients with 3 mitral valve replacements, 2 aortic valve replacements, a double mitral and an aortic valve replacement associated with a tricuspid repair and in 4 cases a perfection of their mitral repair. Early and late surgical mortality was zero. The average follow-up time for our patients was 9

关键词： Mitral Valve Repair Acute Rheumatic Fever Senegal