The ongoing SARS CoV-2 pandemic also known as COVID-19 is a highly infectious and deadly disease that has disrupted socio- economic activities and killed over 500 000 people worldwide during the past six months since it first erupted in Wuhan China in December 2019.While intensive efforts are under way in the developed countries to find a vaccine and cure for the disease, Cameroon and other African countries should not fold their hands and wait , but join the search for new remedies including from cures from traditional herbs while rigorously applying barrier and social distancing measures that have proven effective in in curbing the spread of the disease. Herein we enumerate a short list of research priorities that are feasible in our milieu and that could improve on diagnostics, treatment and prevention of the disease in the short and medium terms. Key Words: SARS CoV-2, COVID-19, research, diagnostics, medicinal plants, traditional medicine, pandemic, Cameroon.
{"title":"Priority Research themes in the fight Against the COVID-19 with particular reference to Cameroon","authors":"V. Titanji","doi":"10.4314/JCAS.V15I3.6","DOIUrl":"https://doi.org/10.4314/JCAS.V15I3.6","url":null,"abstract":"The ongoing SARS CoV-2 pandemic also known as COVID-19 is a highly infectious and deadly disease that has disrupted socio- economic activities and killed over 500 000 people worldwide during the past six months since it first erupted in Wuhan China in December 2019.While intensive efforts are under way in the developed countries to find a vaccine and cure for the disease, Cameroon and other African countries should not fold their hands and wait , but join the search for new remedies including from cures from traditional herbs while rigorously applying barrier and social distancing measures that have proven effective in in curbing the spread of the disease. Herein we enumerate a short list of research priorities that are feasible in our milieu and that could improve on diagnostics, treatment and prevention of the disease in the short and medium terms. \u0000Key Words: SARS CoV-2, COVID-19, research, diagnostics, medicinal plants, traditional medicine, pandemic, Cameroon.","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132005717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Avec les mutations de l’economie mondiale, l’intelligence economique est un outil d’aide ideal pour le dirigeant dans l’objectif de prevenir les risques, saisir les opportunites et anticiper les changements de l’environnement. L’objectif de cet article est non seulement de presenter les enjeux et les perspectives de la pratique de l’intelligence economique par les entreprises au Cameroun mais aussi de faire un etat des lieux a travers une etude empirique aupres des dirigeants de 62 entreprises. Les donnees ont ete collectees a partir d’un questionnaire administre en face a face aupres des dirigeants ou des cadres pouvant nous fournir des informations sur l’activite d’intelligence economique. Les donnees ont fait l’objet d’un traitement statistique a l’aide du logiciel SPSS et la methode du tri a plat a ete utilisee pour analyser les resultats. Il ressort de ces resultats que malgre les grands enjeux que presentent la pratique de l’intelligence economique dans les entreprises, cette derniere est encore a l’etat de gestation et reste incomprise par les dirigeants. Des actions de sensibilisation, de formation, de reseautage et d’implication de tous sont necessaires pour une meilleure implementation par les entreprises au Cameroun. Mots cles : Intelligence economique ; Information strategique ; Veille strategique ; Influence ; Securite informationnelle.
{"title":"La pratique de l’intelligence economique dans les entreprises au Cameroun : Enjeux et perspectives","authors":"H. Hourenatou","doi":"10.4314/JCAS.V15I3.4","DOIUrl":"https://doi.org/10.4314/JCAS.V15I3.4","url":null,"abstract":"Avec les mutations de l’economie mondiale, l’intelligence economique est un outil d’aide ideal pour le dirigeant dans l’objectif de prevenir les risques, saisir les opportunites et anticiper les changements de l’environnement. L’objectif de cet article est non seulement de presenter les enjeux et les perspectives de la pratique de l’intelligence economique par les entreprises au Cameroun mais aussi de faire un etat des lieux a travers une etude empirique aupres des dirigeants de 62 entreprises. Les donnees ont ete collectees a partir d’un questionnaire administre en face a face aupres des dirigeants ou des cadres pouvant nous fournir des informations sur l’activite d’intelligence economique. Les donnees ont fait l’objet d’un traitement statistique a l’aide du logiciel SPSS et la methode du tri a plat a ete utilisee pour analyser les resultats. Il ressort de ces resultats que malgre les grands enjeux que presentent la pratique de l’intelligence economique dans les entreprises, cette derniere est encore a l’etat de gestation et reste incomprise par les dirigeants. Des actions de sensibilisation, de formation, de reseautage et d’implication de tous sont necessaires pour une meilleure implementation par les entreprises au Cameroun. \u0000Mots cles : Intelligence economique ; Information strategique ; Veille strategique ; Influence ; Securite informationnelle.","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126892896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Classical economists were of the view that development is a convoluted process and as such countries can only achieve development through a linear path consisting of five stages. Going by this philosophy, the country under the New Deal Government of Cameroon, by its status is between the traditional stage (stage 1) and the pre-conditions to take-off stage (stage 2). Admitting all efforts are put in place as drivers for take-off stage (emergence or stage 3), it becomes imperative to evaluate the sustainability of this economic emergence. Thus, sustainability drivers such as real gross domestic product per capita, availability of quality agricultural land, energy supply, population growth, enrolment into higher education, foreign direct investments and gross domestic capital formation are evaluated to account for the feasibility of Cameroon’s emergence comes 2035. Based on time series data from 1960 to 2017 inclusive on the above listed variables, and using the Structural Vector-Auto Regressive (SVAR) models, the findings yield some useful policy guides. Subject to pre and post-tests of estimation, forecasting was guaranteed up to 58years outside the data set. With a justified 70.2 percent simulation results, the findings reveal that total natural resources rents can actually pave the way for sustainable growth and development in Cameroon by2035 and beyond. The true direction therefore reveals that, in addition to proper management of the available total natural resource rents, reasonable portion of government expenditure and returns on foreign direct investment should be directed to agricultural research, investment in education especially in science, and technology, engineering and mathematics (STEM) and innovation, rents conservation, infrastructural development, energy supply, population growth and the trade-off of leisure in favour of work. These among others are the gate-ways for sustainable growth, development and hence the emergence of Cameroon in 2035. Keywords: Natural Resources; Rents; Economic Emergence; Real Gross Product Per Capital; Energy Supply; Agricultural Land; Foreign Direct Investment; Gross Domestic Capital Formation and Sustainable Development
{"title":"Natural resources as agents of economic emergence: evidence from Cameroon","authors":"Godfrey Forgha Njimated, Ivan Mboambogoh Yakum","doi":"10.4314/jcas.v15i2.3","DOIUrl":"https://doi.org/10.4314/jcas.v15i2.3","url":null,"abstract":"Classical economists were of the view that development is a convoluted process and as such countries can only achieve development through a linear path consisting of five stages. Going by this philosophy, the country under the New Deal Government of Cameroon, by its status is between the traditional stage (stage 1) and the pre-conditions to take-off stage (stage 2). Admitting all efforts are put in place as drivers for take-off stage (emergence or stage 3), it becomes imperative to evaluate the sustainability of this economic emergence. Thus, sustainability drivers such as real gross domestic product per capita, availability of quality agricultural land, energy supply, population growth, enrolment into higher education, foreign direct investments and gross domestic capital formation are evaluated to account for the feasibility of Cameroon’s emergence comes 2035. Based on time series data from 1960 to 2017 inclusive on the above listed variables, and using the Structural Vector-Auto Regressive (SVAR) models, the findings yield some useful policy guides. Subject to pre and post-tests of estimation, forecasting was guaranteed up to 58years outside the data set. With a justified 70.2 percent simulation results, the findings reveal that total natural resources rents can actually pave the way for sustainable growth and development in Cameroon by2035 and beyond. The true direction therefore reveals that, in addition to proper management of the available total natural resource rents, reasonable portion of government expenditure and returns on foreign direct investment should be directed to agricultural research, investment in education especially in science, and technology, engineering and mathematics (STEM) and innovation, rents conservation, infrastructural development, energy supply, population growth and the trade-off of leisure in favour of work. These among others are the gate-ways for sustainable growth, development and hence the emergence of Cameroon in 2035. Keywords: Natural Resources; Rents; Economic Emergence; Real Gross Product Per Capital; Energy Supply; Agricultural Land; Foreign Direct Investment; Gross Domestic Capital Formation and Sustainable Development","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125916809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Mbah, S. Ayonghe, V. Tanya, V. Titanji, Magellan Guewo-Fokeng
The evidence-based science advice (ESA) effort of the Cameroon Academy of Sciences (CAS) since 23 years has been reviewed. The objective throughout has been to enable science influence policy/decision making at all levels – national, regional and global. The key partners of CAS included the United States National Academy of Sciences (USNAS), the German Academy of Sciences (Leopoldina), the Royal Society of United Kingdom, as well as the Network of African Science Academies (NASAC), the InterAcademy Partnership (Science, Health, Research), the Commonwealth Science Academies and the International Science Council. The mechanisms used included consensus studies, workshops, public lectures, participation in sectoral committees, summaries of key scientific publications and joint statements. Priorities handled through convening activities were triggered by policy/decision making sector requests or Academy foresights. The response/impact of the effort varied from media coverage through policy/programme change/orientation. The major challenges faced included insufficient financial/human resources, inadequate office space, and weak links with government. These challenges must be addressed to enable effective evidence-based science advice which is increasingly unavoidable for sustainable development. Keywords: Evidence-based science, advice, policy, decision-maker
{"title":"The Cameroon Academy of Sciences model of evidence-based science advice","authors":"D. Mbah, S. Ayonghe, V. Tanya, V. Titanji, Magellan Guewo-Fokeng","doi":"10.4314/jcas.v15i2.4","DOIUrl":"https://doi.org/10.4314/jcas.v15i2.4","url":null,"abstract":"The evidence-based science advice (ESA) effort of the Cameroon Academy of Sciences (CAS) since 23 years has been reviewed. The objective throughout has been to enable science influence policy/decision making at all levels – national, regional and global. The key partners of CAS included the United States National Academy of Sciences (USNAS), the German Academy of Sciences (Leopoldina), the Royal Society of United Kingdom, as well as the Network of African Science Academies (NASAC), the InterAcademy Partnership (Science, Health, Research), the Commonwealth Science Academies and the International Science Council. The mechanisms used included consensus studies, workshops, public lectures, participation in sectoral committees, summaries of key scientific publications and joint statements. Priorities handled through convening activities were triggered by policy/decision making sector requests or Academy foresights. The response/impact of the effort varied from media coverage through policy/programme change/orientation. The major challenges faced included insufficient financial/human resources, inadequate office space, and weak links with government. These challenges must be addressed to enable effective evidence-based science advice which is increasingly unavoidable for sustainable development. Keywords: Evidence-based science, advice, policy, decision-maker","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130054359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Saint-Cyr Lengaye, J. Songuele, Jean M'Boliguipa, Ruben Mouangue
Tres souvent en zone rurale et milieu periurbain, on denombre plusieurs sources d’eaux de puits, de sources naturelles et certains marigots qui sont exposees aux differentes intemperies et aux aleas de la nature. Ainsi, la consommation de ces eaux est a l’origine des maladies d’origine hydrique comme l’amibiase, la typhoide, le cholera etc. Le present travail vise a l’amelioration de l’hygiene et de l’environnement en zone rurale et dans certains quartiers peripheriques de Dang et d’autres grandes villes de la region de l’Adamaoua. A ce titre, nous nous proposons de developper un filtre composite a base d’argile et de charbon actif issu des coques de noix de palme pour une large diffusion aupres des populations des zones rurales et periurbaines dans le but de reduire le taux des maladies d’origine hydrique et de faire une etude comparative des analyses physico-chimiques et microbiologiques des quatre echantillons et leur filtrat enfin d’ evaluer le cout du procede par rapport au filtre moderne. La methode adoptee consiste a faire des echantillonnages d’argile et noix de coque de palme suivi d’un traitement physique pour obtenir des poudres d’argile, et puis, d’un traitement physico-chimique pour obtenir des poudres de charbons actifs par une activation thermique avec une temperature de 600 a 900°C. Les resultats obtenus montrent que pour une eau non traitee de turbidite 2NTU, ayant une forte presence (+) de germes pathogenes ( Escherichia colis ), se voit cette caracteristique reduite apres filtration a 1NTU avec une absence totale (/) de ces agents pathogenes. Mots cles: Argile, charbon actif, potabilisation de l’eau, maladie hydrique, filtre composite 2 English Abstract Very often in rural and peri-urban areas, there are several sources of well water, natural springs and some marigots that are exposed to the various bad weather and natural hazards. Thus, the consumption of these waters is at the origin of waterborne diseases such as amoebiasis, typhoid, cholera, etc. This work aims to improve hygiene and the environment in rural areas and in some outlying areas of Dang and other major cities in the Adamawa region. As such, we propose to develop a composite filter based on clay and activated carbon from palm nut hulls for wide dissemination to rural and peri-urban populations in order to reduce the rate of dengue waterborne and to make a comparative study of the physicochemical and microbiological analyzes of the four samples and their filtrate finally to evaluate the cost of the process compared to the modern filter. The method adopted consists in making samples of clay and palm shell walnuts followed by a physical treatment to obtain clay powders, and then a physicochemical treatment to obtain activated carbon powders by a thermal activation with a temperature of 600 to 900 °C. The results obtained show that for an untreated water of turbidity 2NTU, having a strong presence (+) of pathogenic germs ( Escherichia colis ), see this characteristic
在农村和城市周边地区，有许多井水、天然泉水和一些暴露在各种天气和自然灾害中的marigots。因此，饮用这些水是水传播疾病的根源，如阿米巴病、伤寒、霍乱等。这项工作的目的是改善Dang和阿达马瓦地区其他主要城市的农村地区和某些外围地区的卫生和环境。这个头衔了,我们在培养一个复合滤波器A粘土和基本来自棕榈果壳活性炭为广泛传播身旁的农村人口变化,目的是减少水媒疾病率和做一个比较研究分析的四个样品及其理化和微生物滤液最后我们评估过程中的成本相对于现代的过滤器。01.06.00)的方法是做了粘土和棕榈果壳后面是一个物理处理,获取粘土粉,然后,一个活性炭粉末冶金物理化学处理以获得由一家带着温度的热激活600 - 900°C。结果表明，未经处理的浊度为2NTU的水，具有高致病菌(大肠杆菌)的存在(+)，在1NTU过滤后，这一特征降低，完全没有这些病原体(/)。关键词:粘土、活性炭、水净化、水病、复合过滤器2英语摘要在农村和城市周边地区经常有几种井水、天然泉水和一些暴露在各种恶劣天气和自然灾害中的marigots。因此，这些水域的消耗是阿米巴病、伤寒、霍乱等水病的起源。这项工作的目的是改善农村地区以及Dang和阿达马瓦地区其他主要城市的一些边远地区的卫生和环境。As such,《我们打算开发了复合过滤所开展基于clay and carbon从palm nut hulls for wide传播到农村百姓and peri-urban in order to reduce the脾of水上登革热and to make a comparative study of the physicochemical microbiological analyzes of the four样本and their结晶enfin to the cost of the process比较订立to the modern过滤。所采用的方法包括制作粘土和棕榈壳核桃样品，然后进行物理处理以获得粘土粉，然后进行物理化学处理以获得活化碳粉，温度为600至900°C。结果表明，未经处理的浊度为2NTU的水，具有很强的致病性细菌(大肠杆菌)存在(+)，过滤后这一特征降低到1NTU，完全没有这些病原体(/)。关键词:粘土，活性炭，水净化，水源疾病，复合过滤器
{"title":"Etude expérimentale et comparative de filtre composite en argile, charbon actif et filtre moderne à partir des analyses des quatre échantillons des eaux de Dang de la région de l’Adamaoua","authors":"Saint-Cyr Lengaye, J. Songuele, Jean M'Boliguipa, Ruben Mouangue","doi":"10.4314/jcas.v15i2.2","DOIUrl":"https://doi.org/10.4314/jcas.v15i2.2","url":null,"abstract":"Tres souvent en zone rurale et milieu periurbain, on denombre plusieurs sources d’eaux de puits, de sources naturelles et certains marigots qui sont exposees aux differentes intemperies et aux aleas de la nature. Ainsi, la consommation de ces eaux est a l’origine des maladies d’origine hydrique comme l’amibiase, la typhoide, le cholera etc. Le present travail vise a l’amelioration de l’hygiene et de l’environnement en zone rurale et dans certains quartiers peripheriques de Dang et d’autres grandes villes de la region de l’Adamaoua. A ce titre, nous nous proposons de developper un filtre composite a base d’argile et de charbon actif issu des coques de noix de palme pour une large diffusion aupres des populations des zones rurales et periurbaines dans le but de reduire le taux des maladies d’origine hydrique et de faire une etude comparative des analyses physico-chimiques et microbiologiques des quatre echantillons et leur filtrat enfin d’ evaluer le cout du procede par rapport au filtre moderne. La methode adoptee consiste a faire des echantillonnages d’argile et noix de coque de palme suivi d’un traitement physique pour obtenir des poudres d’argile, et puis, d’un traitement physico-chimique pour obtenir des poudres de charbons actifs par une activation thermique avec une temperature de 600 a 900°C. Les resultats obtenus montrent que pour une eau non traitee de turbidite 2NTU, ayant une forte presence (+) de germes pathogenes ( Escherichia colis ), se voit cette caracteristique reduite apres filtration a 1NTU avec une absence totale (/) de ces agents pathogenes. Mots cles: Argile, charbon actif, potabilisation de l’eau, maladie hydrique, filtre composite 2 English Abstract Very often in rural and peri-urban areas, there are several sources of well water, natural springs and some marigots that are exposed to the various bad weather and natural hazards. Thus, the consumption of these waters is at the origin of waterborne diseases such as amoebiasis, typhoid, cholera, etc. This work aims to improve hygiene and the environment in rural areas and in some outlying areas of Dang and other major cities in the Adamawa region. As such, we propose to develop a composite filter based on clay and activated carbon from palm nut hulls for wide dissemination to rural and peri-urban populations in order to reduce the rate of dengue waterborne and to make a comparative study of the physicochemical and microbiological analyzes of the four samples and their filtrate finally to evaluate the cost of the process compared to the modern filter. The method adopted consists in making samples of clay and palm shell walnuts followed by a physical treatment to obtain clay powders, and then a physicochemical treatment to obtain activated carbon powders by a thermal activation with a temperature of 600 to 900 °C. The results obtained show that for an untreated water of turbidity 2NTU, having a strong presence (+) of pathogenic germs ( Escherichia colis ), see this characteristic","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132295670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cette article est une evocation personnelle des differentes phases de l’implantation au Cameroun et en Afrique Centrale du theme de recherche “Epidemiologie Mathematique”. Il analyse egalement les enjeux et les perspectives de ce theme dans une portee pluridisciplinaire. English Abstract This article is the author’s testimony to the successive stages of the setting in Cameroon and Central Africa of the research theme “Mathematical Epidemiology”. It also analyses the challenges and prospects of this theme from a multidisciplinary point of view.
{"title":"Les modèles mathématiques en épidémiologie. L’exécution du testament de Sir Ronald Ross","authors":"David Békollé","doi":"10.4314/jcas.v15i2.1","DOIUrl":"https://doi.org/10.4314/jcas.v15i2.1","url":null,"abstract":"Cette article est une evocation personnelle des differentes phases de l’implantation au Cameroun et en Afrique Centrale du theme de recherche “Epidemiologie Mathematique”. Il analyse egalement les enjeux et les perspectives de ce theme dans une portee pluridisciplinaire. English Abstract This article is the author’s testimony to the successive stages of the setting in Cameroon and Central Africa of the research theme “Mathematical Epidemiology”. It also analyses the challenges and prospects of this theme from a multidisciplinary point of view.","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"211 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115973375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper examines rainfall variability and change as well as drought intensities in the Sudano-Sahelian region of Nigeria with a focus on the sowing season (June - July) and mid-season (August - October) of the farming calendar of rice. Monthly rainfall and rain-days data for Sokoto, Gusau, Katsina, Kano, Potiskum, Nguru, Maiduguri and Yola for 65 years (1951-2015) were sourced from the archives of the Nigerian Meteorological Agency. Rainfall decreased in Katsina and Nguru at annual rates of 0.69mm and 1.12mm respectively while it increased in Sokoto, Gusau, Kano, Potiskum, Maiduguri and Yola at annual rates of 0.39mm, 0.34mm, 03.77mm, 0.18mm and 0.37mm respectively during the sowing season. Rainfall decreased at annual rates of 1.38mm, 1.96mm, 0.57mm, 0.84mm, 0.71mm and 1.54mm in Sokoto, Katsina, Potiskum, Nguru, Maiduguri and Yola respectively while it increased at 2.31mm and 3.70mm in Gusau and Kano respectively. Rainfall changed significantly in Nguru during the sowing season and Sokoto Katsina, Kano, and Yola during the mid-season. Rain-days declined annually at the rate of 0.062, 0.049, 0.058, 0.042, 0.001, 0.083 and 0.070 in Sokoto, Gusau, Katsina, Kano, Potiskum, Nguru and Maiduguri respectively while it increased in Yola at 0.038 during the sowing season. It decreased at annual rates of 0.119, 0.120, 0.079, 0.052, 0.016, 0.006 and 0.316 in Sokoto, Gusau, Katsina, Kano, Potiskum, Nguru and Maiduguri respectively while it increased in Yola at 0.001 during the mid-season. Rain-days changed significantly in Potiskum, Nguru and Maiduguri during the sowing season while it changed significantly in Sokoto, Gusau,, Potiskum and Maiduguri during the mid-season. Generally, droughts were more of slight and moderate intensities with Sokoto having the highest percentages of severe and disastrous categories. Timely weather forecasts and irrigation practice in relation with the different phases during rice farming calendar as well as cultivation of improved varieties are recommended. Keywords: Drought, Mid-season, Rainfall, Rice, Sowing season, Sudano-Sahelian region, Nigeria
{"title":"Rainfall variability and drought during the sowing season and mid-season of rice in the Sudano-Sahelian Region of Nigeria","authors":"G. Atedhor","doi":"10.4314/JCAS.V15I1.4","DOIUrl":"https://doi.org/10.4314/JCAS.V15I1.4","url":null,"abstract":"This paper examines rainfall variability and change as well as drought intensities in the Sudano-Sahelian region of Nigeria with a focus on the sowing season (June - July) and mid-season (August - October) of the farming calendar of rice. Monthly rainfall and rain-days data for Sokoto, Gusau, Katsina, Kano, Potiskum, Nguru, Maiduguri and Yola for 65 years (1951-2015) were sourced from the archives of the Nigerian Meteorological Agency. Rainfall decreased in Katsina and Nguru at annual rates of 0.69mm and 1.12mm respectively while it increased in Sokoto, Gusau, Kano, Potiskum, Maiduguri and Yola at annual rates of 0.39mm, 0.34mm, 03.77mm, 0.18mm and 0.37mm respectively during the sowing season. Rainfall decreased at annual rates of 1.38mm, 1.96mm, 0.57mm, 0.84mm, 0.71mm and 1.54mm in Sokoto, Katsina, Potiskum, Nguru, Maiduguri and Yola respectively while it increased at 2.31mm and 3.70mm in Gusau and Kano respectively. Rainfall changed significantly in Nguru during the sowing season and Sokoto Katsina, Kano, and Yola during the mid-season. Rain-days declined annually at the rate of 0.062, 0.049, 0.058, 0.042, 0.001, 0.083 and 0.070 in Sokoto, Gusau, Katsina, Kano, Potiskum, Nguru and Maiduguri respectively while it increased in Yola at 0.038 during the sowing season. It decreased at annual rates of 0.119, 0.120, 0.079, 0.052, 0.016, 0.006 and 0.316 in Sokoto, Gusau, Katsina, Kano, Potiskum, Nguru and Maiduguri respectively while it increased in Yola at 0.001 during the mid-season. Rain-days changed significantly in Potiskum, Nguru and Maiduguri during the sowing season while it changed significantly in Sokoto, Gusau,, Potiskum and Maiduguri during the mid-season. Generally, droughts were more of slight and moderate intensities with Sokoto having the highest percentages of severe and disastrous categories. Timely weather forecasts and irrigation practice in relation with the different phases during rice farming calendar as well as cultivation of improved varieties are recommended. Keywords: Drought, Mid-season, Rainfall, Rice, Sowing season, Sudano-Sahelian region, Nigeria","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115434847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Data from production and financial records from the Wakwa Centre for Animal and Veterinary Research were used to find out whether or not genetic improvement for dairy production is a profitable investment. The herd projection computer program was used to herd-project the performance of 100 Holstein x Gudali crossbred and 100 Gudali heifers over a 10-year period. Despite the high mortality rate of the crosses, their overall improvement over the local Gudali led to a benefit-cost ratio of 4.21. This suggests that genetic improvement of local cattle through crossbreeding for dairy production can be a profitable venture. Crossbred dairy farming is therefore recommended for the dairy industry in Cameroon. Keywords: Cattle, genetic improvement, milk production, profitability, Cameroon
{"title":"Profitability of agricultural research: the case of genetic improvement of cattle for milk production in Cameroon","authors":"D. Pingpoh, D. Mbah, L. C. Tawah","doi":"10.4314/JCAS.V15I1.1","DOIUrl":"https://doi.org/10.4314/JCAS.V15I1.1","url":null,"abstract":"Data from production and financial records from the Wakwa Centre for Animal and Veterinary Research were used to find out whether or not genetic improvement for dairy production is a profitable investment. The herd projection computer program was used to herd-project the performance of 100 Holstein x Gudali crossbred and 100 Gudali heifers over a 10-year period. Despite the high mortality rate of the crosses, their overall improvement over the local Gudali led to a benefit-cost ratio of 4.21. This suggests that genetic improvement of local cattle through crossbreeding for dairy production can be a profitable venture. Crossbred dairy farming is therefore recommended for the dairy industry in Cameroon. Keywords: Cattle, genetic improvement, milk production, profitability, Cameroon","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129483467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Le tambour d’appel africain (TAA) est le vehicule sonore de l’existence africaine. Il est associe a de nombreuses expressions traditionnelles et cultuelles. Le processus de fabrication presente quelques inconvenients : duree longue, difficulte a fabriquer des tambours acoustiquement identiques, pauvrete tonale et portee acoustique limitee. Dans le but d’apporter quelques solutions aux inconvenients susmentionnes, nous etablissons les equations dynamiques du fonctionnement du TAA grâce aux lois de la mecanique et de l’acoustique. Les frequences propres de vibration des levres et de la cavite sont obtenues. Deux formules scientifiques qui permettent d’optimiser la reponse acoustique des TAAs sont etablies. Elles peuvent servir comme normes de fabrication afin d’obtenir des puissances sonores maximales et de gerer convenablement les intervalles musicaux. Les resultats theoriques sont valides par des mesures experimentales et des tests dans des ateliers de fabrication. Mots cles: Tambour d’appel africain, frequences propres, formules scientifiques, optimisation de la fabrication English Abstract The African calling drum is a sound instrument associated to various traditional and cultural expressions in Africa. Its fabrication process presents some limits: long duration, difficulty in fabricating acoustically identical drums, tonal poverty and limited sound range. In order to find some solutions to these limits, dynamical equations describing the functioning of the African calling drum are derived using mechanical and acoustical laws. The natural frequencies of vibration of the drum shells and drum cavity are obtained. They are used to obtain formula for the fabrication of drums with maximal sound powers and convenient management of the musical intervals. The theoretical results are validated by the experiment and tests in some fabrication sites. Keywords: African calling drum, natural frequencies, scientific formula, optimization of the fabrication
非洲呼叫鼓(TAA)是非洲存在的声音载体。它与许多传统和宗教表达有关。制作过程中存在一些缺点:制作声音相同的鼓很困难，音调差，音域有限。为了解决上述缺点，我们利用力学和声学定律建立了TAA运行的动力学方程。得到了嘴唇和腔体的固有振动频率。提出了两种优化TAAs声学响应的科学公式。它们可以作为制造标准，以获得最大的声音功率和适当管理音乐间隔。理论结果通过制造车间的实验测量和测试得到验证。关键词:非洲呼鼓，自己的频率，科学公式，制造优化英语摘要非洲呼鼓是一种与非洲各种传统和文化表达相关的声音乐器。它的制作过程有一些限制:长度长、制作声音相同的鼓困难、音调差和音域有限。怎么解释办法to these In order to find limits, dynamical方程和of the African are calling drum)他使用毒性mechanical and acoustical laws。The natural frequencies of振动are of The drum shell drum隔热,温度。您用They are used to formula for the powers of sound最大鼓with and制造用音乐management of the名誉的人。该理论结果已在一些生产现场的实验和测试中得到验证。关键词:非洲鼓，自然频率，科学配方，制造优化
{"title":"Formules scientifiques pour l’optimisation de la réponse acoustique du tambour d’appel africain","authors":"J. H. T. Mbé, Paul Woafo, J. Ndongo","doi":"10.4314/JCAS.V15I1.5","DOIUrl":"https://doi.org/10.4314/JCAS.V15I1.5","url":null,"abstract":"Le tambour d’appel africain (TAA) est le vehicule sonore de l’existence africaine. Il est associe a de nombreuses expressions traditionnelles et cultuelles. Le processus de fabrication presente quelques inconvenients : duree longue, difficulte a fabriquer des tambours acoustiquement identiques, pauvrete tonale et portee acoustique limitee. Dans le but d’apporter quelques solutions aux inconvenients susmentionnes, nous etablissons les equations dynamiques du fonctionnement du TAA grâce aux lois de la mecanique et de l’acoustique. Les frequences propres de vibration des levres et de la cavite sont obtenues. Deux formules scientifiques qui permettent d’optimiser la reponse acoustique des TAAs sont etablies. Elles peuvent servir comme normes de fabrication afin d’obtenir des puissances sonores maximales et de gerer convenablement les intervalles musicaux. Les resultats theoriques sont valides par des mesures experimentales et des tests dans des ateliers de fabrication. Mots cles: Tambour d’appel africain, frequences propres, formules scientifiques, optimisation de la fabrication English Abstract The African calling drum is a sound instrument associated to various traditional and cultural expressions in Africa. Its fabrication process presents some limits: long duration, difficulty in fabricating acoustically identical drums, tonal poverty and limited sound range. In order to find some solutions to these limits, dynamical equations describing the functioning of the African calling drum are derived using mechanical and acoustical laws. The natural frequencies of vibration of the drum shells and drum cavity are obtained. They are used to obtain formula for the fabrication of drums with maximal sound powers and convenient management of the musical intervals. The theoretical results are validated by the experiment and tests in some fabrication sites. Keywords: African calling drum, natural frequencies, scientific formula, optimization of the fabrication","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114196762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Fantong, Clifford Ngappe, Hycinth S. Banseka, M. Fonteh, Hubert Onibon, E. C. Fru, E. Yanne, Bertold D. Dontsa Tsafack, S. Ayonghe
With fluoride-rich groundwater causing a climatic-dependent fluorosis in Mayo-Tsanaga River Basin, the overall objective of this study was to reduce fluoride concentrations in drinking water to acceptable levels thereby improving the resilience of the population to this climate change induced pathology. The specific objectives were to: (1) assess water chemistry in the study area to re-affirm the undesirable fluoride levels; (2) assess the impact of seasons on the concentrations of fluoride; (3) construct and evaluate the performance of a household bone char-based adsorption defluoridation filter. A combination of hydrogeochemical and engineering analyses demonstrated that the groundwater is predominantly Ca + Mg - HCO 3 type, which contains as much as 6.73 mg/l of undesirable concentrations of geogenic fluoride. These concentrations increased with elevated pH, electrical conductivity and in the dry season, and were reduced to less than 0.2 mg/l when the groundwater was subjected to filtration through 300 g of 0.2-0.8 mm faction of charred cow bones in a home-based defluoridation filter. The bone char in the filter can effectively reduce fluoride concentration to less than 0.7 mg/l, which is the local threshold limit, without negative impact on the organoleptic (taste, color and odor) characteristics of drinking water. Compared with the commercially activated carbon, the bone char has an additional capacity of adsorbing fluoride at a rate of 4 mg/liter in 30 minutes, which indicates that with a defined saturation time, the bone char filter can protect the population against climate change-induced fluoride enrichment in drinking water. Keywords: Groundwater. geogenic fluoride. climate dependent fluorosis. bone char defluoridation. water chemistry
{"title":"Defluoridation of fluoride-rich groundwater in Mayo Tsanaga River Basin-Cameroon using locally produced bone char","authors":"W. Fantong, Clifford Ngappe, Hycinth S. Banseka, M. Fonteh, Hubert Onibon, E. C. Fru, E. Yanne, Bertold D. Dontsa Tsafack, S. Ayonghe","doi":"10.4314/JCAS.V15I1.2","DOIUrl":"https://doi.org/10.4314/JCAS.V15I1.2","url":null,"abstract":"With fluoride-rich groundwater causing a climatic-dependent fluorosis in Mayo-Tsanaga River Basin, the overall objective of this study was to reduce fluoride concentrations in drinking water to acceptable levels thereby improving the resilience of the population to this climate change induced pathology. The specific objectives were to: (1) assess water chemistry in the study area to re-affirm the undesirable fluoride levels; (2) assess the impact of seasons on the concentrations of fluoride; (3) construct and evaluate the performance of a household bone char-based adsorption defluoridation filter. A combination of hydrogeochemical and engineering analyses demonstrated that the groundwater is predominantly Ca + Mg - HCO 3 type, which contains as much as 6.73 mg/l of undesirable concentrations of geogenic fluoride. These concentrations increased with elevated pH, electrical conductivity and in the dry season, and were reduced to less than 0.2 mg/l when the groundwater was subjected to filtration through 300 g of 0.2-0.8 mm faction of charred cow bones in a home-based defluoridation filter. The bone char in the filter can effectively reduce fluoride concentration to less than 0.7 mg/l, which is the local threshold limit, without negative impact on the organoleptic (taste, color and odor) characteristics of drinking water. Compared with the commercially activated carbon, the bone char has an additional capacity of adsorbing fluoride at a rate of 4 mg/liter in 30 minutes, which indicates that with a defined saturation time, the bone char filter can protect the population against climate change-induced fluoride enrichment in drinking water. Keywords: Groundwater. geogenic fluoride. climate dependent fluorosis. bone char defluoridation. water chemistry","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"82 5‐6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133135089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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