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Effect of different Rates and Mixtures of Solid Household Waste and Faecal Sludge-Based Composts on Soil Fertility and Productivity of Sunflower (Helianthus annuus L.) in dschang, West Cameroon

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Open Journal of Soil Science 2024年第7期14卷 448-470页

作者： Romary Ngnipa Tchinda Rodrigue Emmanuel Kenne Primus Azinwi Tamfuh Jovanie Gladys Kenfack doris Temgoua Zombou désiré évariste moundjeu Tsafack Richard Tanwi Ghogomu Emile Temgoua dieudonné Bitom Oyono department of Environmental Sciences of the Higher Institute of Agriculture Wood Water and the Environment of the University of Bertoua Blabo Cameroon department of Soil Science Soil Analysis and Environmental Chemistry Research Unit Faculty of Agronomy and Agricultural Sciences University of Dschang Dschang Cameroon department of Mining and Mineral Engineering National Higher Polytechnic Institute University of Bamenda Bambili Cameroon department of Animal Biology Faculty of Sciences University of Dschang Dschang Cameroon department of Earth Sciences University of Yaounde 1 Yaounde Cameroon

The unbalanced and inadequate use of fertilizers is one of the causes of soil degradation. Combined with the ever-increasing population, it is necessary to find sustainable agricultural production alternatives. The present work aims to determine the effect of different rates and mixtutes of organic amendments on soil fertility and the performance of Sunflower (Helianthus annuus L.). In the field, treatments consisted of solid household waste and faecal sludge in the ratios of 3/5 (V1), and a mixture of faecal sludge and household waste in the ratio of 3/5 with 900 worms (V2). At the end of the composting process, V1, V2 composts and the poultry manure (PM) were applied at rates of 4, 5 and 6 t∙ha−1 in a randomized complete block design with three replications. Soil samples were collected before and after the experiment and analyzed. The main results revealed that at the end of the composting process, there was a progressive improvement in the physico-chemical properties of V1 and V2 composts. In particular, the C/N ratio, phosphorus (P) and total nitrogen (TN) initially at 16.49 ± 0.42 (V1, V2), 21.06 ± 0.07 mg∙kg−1 (V1, V2), 0.76% ± 0.08% (V1, V2) respectively, increased after 60 days to 12.40 ± 0.41 (V1), 9.74 ± 0.28 (V2) for C/N, 21.94 ± 0.63 mg∙kg−1 (V1) and 22.04 ± 0.04 mg∙kg−1 (V2) for P, 0.96% ± 0.0% (V1) and 1.22 ± 0.04 (V2) for TN. The application of 6 t∙ha−1of PM had the greatest influence on the diameter and weight of the flower heads (27.16 ± 4.01 t∙ha−1 and 230.83 ± 2.64 t∙ha−1), while 4 t∙ha−1 of V2 gave the tallest sunflower plants (110.07 ± 73.28 cm) as well as the diameter at the crown (19.30 ± 9.07 cm). However, CEC was most influenced by 4 t∙ha−1 of V1, while 4 t∙ha−1 of PM had the greatest effect on organic carbon and phosphorus. However, 5 t∙ha−1 of PM showed the highest sunflower production and yield (1.67 ± 0.21 t∙ha−1). The combination with 900 earthworms is recommended for composting and 5 t∙ha−1 of PM is recommended to obtain a better sunfl

关键词： Sunflower Faecal Sludge Household Waste Compost Soil Fertility

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Ethics of Human Resources Management in the Cameroonian Health System, Medical Nomadism and the Ineffectiveness of the Fight against High Blood Pressure

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Health 2024年第1期16卷 9-21页

作者： Jean Ndibi Abanda Anicet Onana Akoa désiré Tchoffo Ulrich dama Pierre Yassa Yoniene Faculty of Health Sciences University of Lisala (CIREP-UNILIS) Lisala Democratic Republic of the Congo National Order of Medical and Sanitary Professions Yaounde Cameroon School of Health Sciences Catholic University of Central Africa Yaounde Cameroon World Health Organization Maroua Cameroon Faculty of Medicine University Simon Kimbangu Kinshasa Democratic Republic of the Congo

Context/objectives: The fight against Chronic Non-Communicable diseases (NCds) is a long-term undertaking, which requires available, motivated and well-managed human resources (HR). The administrative management of skills on both qualitative and quantitative levels is one of the essential functions of a health system. To better implement policies of fight against High Blood Pressure (HBP) and other chronic diseases, it is important to establish strategies to retain health personnel. This loyalty requires favorable working conditions and consideration of the contribution-reward couple. Good working conditions are likely to reduce the phenomenon of medical nomadism;conversely, poor HR management can contribute to their exodus towards exotic “green pastures”, thus leading to an additional crisis in the Cameroonian health system. The fight against HBP is a complex, multifaceted and multifactorial reality that requires appropriate management model for all types of resources mainly HR. The main objective of this research is to show the impact of poor management of human resources in Cameroon health system on medical nomadism and the ineffectiveness of the fight against High Blood Pressure. Method: A cross-sectional descriptive survey among five hundred (500) health facilities in the center region of Cameroon has been conducted. A stratified probabilistic technique has been used, and the number of health facilities to be surveyed has been determined using the “sample size estimation table” of depelteau. The physical questionnaires have been printed and then distributed to data collectors. After data collection, the latter were grouped during processing in Excel sheets. The Chi-square test was used for data with a qualitative value and that of Kolmogorov-Sminorf for data with a quantitative value to assess the normality and reliability of data. The Crochach’s Alpha reliability test allowed us to have a summary of the means and variances and then to search for intragroup cor

关键词： Ethics Human Resources Management Cameroonian Health System Medical Nomadism Ineffectiveness High Blood Pressure

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Effect of Size and Initial Water Content on the Effective diffusion Coefficient during Convective drying of Sweet Potato Cut into Cubic and Cylindrical Shapes

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Journal of Materials Science and Chemical Engineering 2024年第6期12卷 71-82页

作者： Ibrango Abdoul Salam Ouoba Kondia Honoré Bama désiré Traoré Yssa Zongo Karim Ouedraogo Salifou Laboratoire de Matriaux de lHliophysique et Environnement (La.M.H.E.) Unit de Formation et de Recherche en Sciences. Exactes et Appliques (UFR/SEA) Universit Nazi BONI de Bobo-Dioulasso Bobo-Dioulasso Burkina Faso

In this article, we investigated the influence of size and initial water content on the effective diffusion coefficient of sweet potatoes samples cut into cubic and cylindrical shapes. The sizes of the cubic samples are 0.5, 1, 1.5, 1.75, 2, 2.5 and 3 cm edge with a respective initial water content of 2.7, 3.76, 3.48, 2.68, 3.28, 2.17 and 2.29 kg/kgms. For cylindrical samples, the radius is set at 0.5 cm and sample heights are 1, 1.5, 2, 2.5, 3, 3.5 and 4 cm with respective water contents of 2.2, 3.19, 2.85, 2.1, 2.17, 2.39 and 2.03 kg/kgms. The effective diffusion coefficients of cubic samples are of the order of 10−10 and 10−9 m2∙s−1 grew with sample edge. As for the cylindrical samples, the effective diffusion coefficients were of the order of 10−9 m2∙s−1 and there was no linear correlation between cylinder height and their effective diffusion coefficient. As for the examination of the initial water content on the effective diffusion coefficient, it turned out that the initial water content had no influence on the effective diffusion coefficient of the sweet potato samples.

关键词： Effective diffusion Coefficient Initial Water Content Sweet Potato Cubic Cylindrical

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Pattern of Potential Laboratory Markers for COVId-19 in Eastern Sudan

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Open Journal of Epidemiology 2024年第3期14卷 508-516页

作者： Nazik sir El Khatim Bakhit Suliman Mohammed Omer Abaker Gibreel Mervat sir El Khatim Bakhit Suliman department of Clinical Chemistry College of Medical Laboratory Science Eastern Sudan University of Medical Science and Technology Port Sudan Sudan dean of the Secretariat of Academic Affairs Port Sudan Ahlia University Port Sudan Sudan Cardiology department Cath Lab Fujaira Hospital Fujaira UAE

Background: Coronavirus disease 2019 (COVId-19) is a recent global health crisis. One of the major issues of COVId-19 is its unpredictable manifestations and serious outcomes. Many hematological parameters are thought to change dramatically during the course of the disease. These include white blood cells, red blood cells, and platelets. This study aimed at evaluating certain laboratory results;peripheral blood lymphopenia, relative neutrophilia, high neutrophil-lymphocyte ratio, and elevated C-reactive protein as potential laboratory markers of COVId-19 in Eastern Sudanese patients. Methods: We, retrospectively, aimed at the evaluation of peripheral blood leucocytes count, neutrophil-lymphocyte ratio NLR and C-reactive protein (CRP) levels in confirmed COVId-19 eastern Sudanese patients during the course of the disease. Results: The mean total leucocytes count, % neutrophils count, absolute neutrophils count and C-reactive protein (CRP) were significantly higher (P. value = 0.000) in COVId-19 patients than in the control group while the mean % lymphocytes count and % mixed cells count were found to be significantly lower in COVId-19 patients than in the control group (P. value 0.000). Conclusion: Peripheral blood leucocyte alterations (simultaneous presence of lymphopenia, relative neutrophilia and high neutrophil lymphocyte ratio (NLR) along with elevated CRP levels may be valuable biomarkers associated with COVId-19 in Port Sudan city, Red Sea state, Sudan. These markers might be important in prediction, inspection of disease progression and prognosis.

关键词： COVId-19 SARS 2 WBCs CRP NLR Port Sudan

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Experimental Assessment of the Thermal Performance of Two Corrugated Metal Roofs

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Open Journal of Applied Sciences 2024年第9期14卷 2374-2392页

作者： Kouamé Jean-Louis Kouakou Ekoun Paul Magloire Koffi Bi Tra désiré Zinla Prosper Gbaha Laboratoire des Procds Industriels de Synthse de lEnvironnement et des Energies Nouvelles Institut National Polytechnique Felix Houphout-Boigny Yamoussoukro Cte dIvoire

This experimental study is a contribution to the search for solutions to reduce indoor heat gain through sheet metal roofing in hot weather. It has evaluated the thermal impact of two different sheet metal roofs inside of two identical test buildings in sunny weather and cloudy weather conditions. Test building 1 has a single sheet corrugated roof and the building 2 is covered with roof made from top to bottom with corrugated sheet metal, a 12 mm thick serpentine copper tube in which water is circulated, a sheet of aluminium foil acting as a heat reflector, a 4 cm thick polystyrene panel and a 1.5 cm thick plywood. A maximum reduction of 15.1˚C in the temperature of the inner face of the test Building 2 roof was obtained comparatively to the temperature of the inner face of the test Building 1 roof consisting of a single sheet of metal at the warmest hours. In addition, the simple corrugated sheet metal roof of the test building generates high and varied temperatures inside the building. Whereas the proposed heat recovery roof favours low and relatively uniform temperatures inside the building. The proposed sheet metal roof construction technique is very effective in reducing the heat gain through the roof considerably;thus improving the thermal comfort inside sheet metal roofed dwellings. Hot water has been produced by recovering heat from the metal sheet of the roof of test building 2. The temperature of the hot water produced reached of 39˚C. This study could be also an alternative for the reduction of energy consumption due to the use of mechanical means for cooling of sheet metal roofed houses and the reduction of the use of fossil fuels for domestic hot water production.

关键词： Metal Roof Corrugated Time Lag decrement Factor

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Coordination of Regulation devices for damping Power Oscillations in a dynamic disturbance Context: A Fuzzy Logic-Based Approach Applied to the Electrical Grid of the Republic of Congo

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Journal of Power and Energy Engineering 2024年第1期12卷 44-60页

作者： Mavie Grace Mimiesse davy Rostand Souamy Loembe Smaël Magloire Elombo Motoula désiré Lilongo-Boyenga Laboratoire du Génie É lectrique et &#201lectronique &#201cole Nationale Supérieure Polytechnique Université Marien NGOUABI Brazzaville Congo Institut Supérieur d’Architecture Urbanisme Batiment et Travaux Punlics Université Dénis SASSOU-N’GUESSO Kintelé Congo

This article presents a fuzzy logic-based approach to coordinate the control devices of the power system, such as Power System Stabilizers (PSS) and Static Synchronous Compensators (STATCOM), to damp power oscillations caused by dynamic disturbances. At first, we used the Lyapunov method to study the dynamic stability of the power grid in the Republic of Congo. This method allowed us to analyze the eigenvalues of the state variable matrix and highlight the eigenvalues in the complex plane. Secondly, we proposed a fuzzy logic-based controller to account for uncertainties existing near the thresholds. The inputs to this controller are the generator speed and generator rotor angle. We demonstrated the effectiveness and feasibility of this fuzzy control by applying it to the power grid of the Republic of Congo, with three power stabilizers and two STATCOMs. .

关键词： Fuzzy Logic STATCOM PSS Lyapunov Republic of Congo

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Life Cycle Assessment of Cashew Nutshell Briquettes Produced in Côte d’Ivoire

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Open Journal of Applied Sciences 2024年第9期14卷 2411-2430页

作者： Bi Tra désiré Zinla Ekoun Paul Magloire Koffi Kamenan Blaise Koua Kpeusseu Angeline Kouambla Epse Yeo Prosper Gbaha Laboratoire des Procds Industriels de Synthse de lEnvironnement et des Energies Nouvelles Institut National Polytechnique Felix Houphout-Boigny Yamoussoukro Cte dIvoire Laboratoire des Sciences de la Matire de lEnvironnement et de lEnergie Solaire Unit de Formation et de Recherche des Sciences des Structures de la Matire et de Technologie Universit Felix Houphout-Boigny Abidjan Cte dIvoire

Now one of the main cash crops in Côte d’Ivoire, the cashew tree feeds an entire industrial sector based on the processing of its fruit. This processing generates a large volume of waste, consisting of cashew nutshells, the management of which poses environmental problems. With the aim of replacing charcoal and firewood with more environmentally friendly fuels, several studies are currently being carried out into the optimal use of cashew shells in fuel briquettes. To assess the environmental sustainability of these briquettes, this study calculates the environmental impacts associated with their life cycle, compares them with those of charcoal and firewood, and identifies the processes that contribute most to environmental pollution, with a view to improving them. Analysis of the results showed that cashew nutshell briquettes emit a range of pollutants over their life cycle that damage the environment and are responsible for the 7 impact categories considered: acidification, eutrophication, freshwater aquatic ecotoxicity, global warming, human toxicity, photochemical oxidation and terrestrial ecotoxicity potential. However, they are more environmentally friendly than charcoal and firewood for 5 impact categories: freshwater aquatic ecotoxicity, global warming, human toxicity, photochemical oxidation and terrestrial ecotoxicity potential. The 3 elementary processes, i.e. transport of biomass raw materials, production, and combustion of briquettes, emit pollutants that contribute most to the creation of environmental impact categories. The most relevant pollutants are nitrogen oxides (NOx), sulphur oxides (SOx) and particulate matter (PM).

关键词： LCA Briquettes Cashew Nutshell Biomass Environmental Impact

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Mobility of Major and Trace Elements during the Bauxitization Processes in Ngaoundal Area (Adamawa Cameroon): Implication on Mining Perspectives

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Open Journal of Geology 2024年第1期14卷 81-100页

作者： André Sini Harouna Boukari Ondoa Augustin désiré Balla djetenbe Beral Salomon Wangmené Awé Simon djakba Basga Jean Pierre Nguetnkam department of Mining Engineering School of Geology and Mining Engineering University of Ngaoundere Ngaoundere Cameroon department of Mining Engineering and Environment School of Mining Industry and Geology University of Abdou-Moumouni Niamey Niger department of Earth Sciences Faculty of Science University of Ngaoundere Ngaoundere Cameroon department of Mining Engineering Saint Jerome Polytechnic Saint Jerome Catholic University Institute of Douala Douala Cameroon Institute of Agricultural Research for development (IRAd) Garoua Cameroon

This study was focused to assess major and trace elements in bauxitic duricrusts from Ngaoundal and its surroundings in order to establish their mining interest. To this end, fieldworks, mineralogical and geochemical analyses were carried out. Four facies of duricrust were identified and characterized from the summit to the top of the slope of the Ngaoundal mountain: scoriaceous, pisolitic, nodular and massive. Mineralogical and geochemical analyses performed on 16 samples, revealed a significant concentration of Al2O3 mainly in the scoriaceous facies (over 45% in grade), moderate in Fe2O3 (averaging 23.69%) and SiO2 (averaging 21.7%). Trace elements were generally low, excluding Cr (421 ppm on average), Zr (327 ppm on average and V (213 ppm on average). In addition, the limited quantities of alkalis (Na2O, K2O) and alkaline earths metals (MgO, CaO) coupled with the very high values of Chemical Index of Alteration (CIA) and Mineralogical Index of Alteration (MIA), (more than 99%) attest to the intense weathering of the studied materials. Allitization and monosiallitization constituted the crystallochemical phenomena that have led to the development of bauxitic minerals. More than 90% of gibbsite in scoriaceous facies, 52.21% - 76.01% of kaolinite in pisolitic facies and more than 40% of hematite in nodular facies were quantified. The relationships between the constitutive components indicated their interdependency during the bauxitization phenomenon. The mineralogical and geochemical properties highlighted the mining interest of the studied duricrusts to be valorized.

关键词： duricrust Bauxitization Phenomenon Mineralogical and Geochemical Characterization Major and Trace Elements Mining Potential

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Lighting up aggregate emission of perylene diimide by leveraging polymerization-mediated through-space charge transfer and π-π stacking

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Science China Chemistry 2024年

作者： Suiying Ye désirée Füglistaller Tian Tian Anjay Manian Sudhir Kumar Celine Nardo Andrew J.Christofferson Salvy P.Russo Chih-Jen Shih Jean-Christophe Leroux Yinyin Bao Institute of Pharmaceutical Sciences Department of Chemistry and Applied Biosciences ETH Zurich Vladimir-Prelog-Weg 3 Institute for Chemical and Bioengineering Department of Chemistry and Applied Biosciences ETH Zurich Vladimir-Prelog-Weg 1-5 ARC Centre of Excellence in Exciton Science School of Science RMIT University School of Science STEM College RMIT University

The molecular engineering of fluorescent organic/polymeric materials, specifically those emitting in the deep red to near-infrared spectrum, is vital for advancements in optoelectronics and biomedicine. Perylene diimide(PdI), a well-known fluorescent scaffold, offers high thermal and photophysical stability but suffers from fluorescence quenching in solid or aggregate states due to intense π-π interactions. To mitigate this, simple and versatile methods for strong PdI aggregate emission without extensive synthetic demands are highly desirable but still lacking. Here, we report a straightforward strategy to enhance the solid-state emission of PdI by introducing certain degree of through-space charge transfer(TSCT) via controlled radical polymerization,which can efficiently distort the typical face-to-face PdI stacking, enabling greatly enhanced deep red emission. This is achieved by growing electron-donating star-shape styrenic(co)polymers from a multidirectional electron-accepting PdI initiator. The incorporation of polycyclic aromatic monomers further shifted the emission into the near-infrared region, albeit with a reduced intensity. Overall, the emission of the PdI-based TSCT polymers can be systematically manipulated by leveraging the balance between PdI stacking and the TSCT degree, as confirmed by both experimental study and theoretical calculations. Our approach circumvents complex synthetic procedures, offering highly emissive materials with large Stokes shifts and showing broad potential for optoelectronic technology.

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Physical Transformations on Organic Product during Its Convective drying: Case of Sweet Potato

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Journal of Biophysical Chemistry 2024年第2期15卷 25-34页

作者： Ouoba Kondia Honoré Ganamé Abdou-Salam Compaoré Aboubakar Ibrango Abdoul Salam Bama désiré Zougmoré Francois desmorieux Hélène Laboratoire de Matriaux de lHliophysique et Environnement (La.M.H.E.) Unit de Formation et de Recherche en Sciences Exactes et Appliques (UFR/SEA) Universit Nazi BONI Bobo Dioulasso Burkina Faso Laboratoire des Matriaux et Environnement (LA.M.E.) Unit de Formation et de Recherche en Sciences Exactes et Applique (UFR/SEA) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire de Physique et de Chimie de lEnvironnement (LPCE) Ecole Doctorale Sciences et Technologie (ED-ST) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire dAutomatique et de Gnie des Procds(LAGEP) Universit Claude Bernard Lyon France

This study highlighted the physical transformation that agri-food products undergo during their drying. This transformation enormously affects the customer’s choice and the profit margin of the dried product promoter. The example of the experimental study of the potato reveals that the product continually changes its dimensions during its drying. The more the product loses its water, the more the dimensions decrease. The results initially showed that the water parameters such as mass or water content decrease according to the drying principle. The dimensions length L., width l and thickness e. decrease following a linear trend whose mathematical equations which describe them are determined using the office tool, excel. This trend has repercussions on the surface and volume parameters which in turn decreases almost linearly with the product’s water content. Note that the coefficient R2 is not always acceptable, confirming the complex nature of the behavior of organic products.

关键词： dimensions Reduction Shrinkage Index I

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