34 research outputs found

    Evidence of Balanced Diversity at the Chicken Interleukin 4 Receptor Alpha Chain Locus

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    Background: The comparative analysis of genome sequences emerging for several avian species with thefully sequenced chicken genome enables the genome-wide investigation of selective processes infunctionally important chicken genes. In particular, because of pathogenic challenges it is expected thatgenes involved in the chicken immune system are subject to particularly strong adaptive pressure.Signatures of selection detected by inter-species comparison may then be investigated at the populationlevel in global chicken populations to highlight potentially relevant functional polymorphisms.Results: Comparative evolutionary analysis of chicken (Gallus gallus) and zebra finch (Taeniopygia guttata)genes identified interleukin 4 receptor alpha-chain (IL-4Rα), a key cytokine receptor as a candidate with asignificant excess of substitutions at nonsynonymous sites, suggestive of adaptive evolution. Resequencingand detailed population genetic analysis of this gene in diverse village chickens from Asia and Africa,commercial broilers, and in outgroup species red jungle fowl (JF), grey JF, Ceylon JF, green JF, grey francolinand bamboo partridge, suggested elevated and balanced diversity across all populations at this gene, actingto preserve different high-frequency alleles at two nonsynonymous sites.Conclusion: Haplotype networks indicate that red JF is the primary contributor of diversity at chickenIL-4Rα: the signature of variation observed here may be due to the effects of domestication, admixtureand introgression, which produce high diversity. However, this gene is a key cytokine-binding receptor inthe immune system, so balancing selection related to the host response to pathogens cannot be excluded

    Evidence of balanced diversity at the chicken interleukin 4 receptor alpha chain locus

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    <p>Abstract</p> <p>Background</p> <p>The comparative analysis of genome sequences emerging for several avian species with the fully sequenced chicken genome enables the genome-wide investigation of selective processes in functionally important chicken genes. In particular, because of pathogenic challenges it is expected that genes involved in the chicken immune system are subject to particularly strong adaptive pressure. Signatures of selection detected by inter-species comparison may then be investigated at the population level in global chicken populations to highlight potentially relevant functional polymorphisms.</p> <p>Results</p> <p>Comparative evolutionary analysis of chicken (<it>Gallus gallus</it>) and zebra finch (<it>Taeniopygia guttata</it>) genes identified interleukin 4 receptor alpha-chain (IL-4Rα), a key cytokine receptor as a candidate with a significant excess of substitutions at nonsynonymous sites, suggestive of adaptive evolution. Resequencing and detailed population genetic analysis of this gene in diverse village chickens from Asia and Africa, commercial broilers, and in outgroup species red jungle fowl (JF), grey JF, Ceylon JF, green JF, grey francolin and bamboo partridge, suggested elevated and balanced diversity across all populations at this gene, acting to preserve different high-frequency alleles at two nonsynonymous sites.</p> <p>Conclusion</p> <p>Haplotype networks indicate that red JF is the primary contributor of diversity at chicken IL-4Rα: the signature of variation observed here may be due to the effects of domestication, admixture and introgression, which produce high diversity. However, this gene is a key cytokine-binding receptor in the immune system, so balancing selection related to the host response to pathogens cannot be excluded.</p

    Amélioration génétique.

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    Le processus de production de semences commerciales; Le processus d'obtention de nouvelles variétés.bitstream/item/142513/1/Amelioration-genetique.pdfCOTON-

    Effects of customized climate services on land and labor productivity in Burkina Faso and Ghana

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    Climate services favor adopting strategies to increase agricultural productivity, enhance sustainable development, and adapt to unavoidable climate variability and change. However, for climates services to be effective, they must be accessible and suitable to user needs. This study investigated the effects of customized climate services (CCS) on land and labor productivity. Portraying the case of CCS delivered in the districts of Bolgatanga (Northern Ghana), Dano and Ouahigouya (western and northern Burkina Faso) in West Africa, it used: i) historical panel data of daily rainfall, yields, agricultural input, and output prices; ii) cost statements of farm operations and iii) other survey data from beneficiaries of on-farm demonstrations (pilot sites). Different results were found across farmers on the demonstrator sites, with Dano and Bolgatanga recording the best land and labor productivity. Strong and positive effects were observed in Dano, where land productivity increased by 200% and labor productivity doubled despite consecutive pluviometric extremes such as heavy rain events and prolonged dry spells in the 2017 and 2018 cropping seasons. Further investigation showed that CCS was particularly favorable to land and labor productivity of farmers who were committed to the advisory given by the CCS providers. Therefore, as perishable goods, the success of CCS applications would require thorough coproduction, delivery, and monitoring for their effectiveness in improving land and labor productivity for agriculture in semi-arid regions of West Africa

    Challenges of scaling up and of knowledge transfer in an action research project in Burkina Faso to exempt the worst-off from health care user fees

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    <p>Abstract</p> <p>Background</p> <p>Systems to exempt the indigent from user fees have been put in place to prevent the worst-off from being excluded from health care services for lack of funds. Yet the implementation of these mechanisms is as rare as the operational research on this topic. This article analyzes an action research project aimed at finding an appropriate solution to make health care accessible to the indigent in a rural district of Burkina Faso.</p> <p>Research</p> <p>This action research project was initiated in 2007 to study the feasibility and effectiveness of a community-based, participative and financially sustainable process for exempting the indigent from user fees. A interdisciplinary team of researchers from Burkina Faso and Canada was mobilized to document this action research project.</p> <p>Results and knowledge sharing</p> <p>The action process was very well received. Indigent selection was effective and strengthened local solidarity, but coverage was reduced by the lack of local financial resources. Furthermore, the indigent have many other needs that cannot be addressed by exemption from user fees. Several knowledge transfer strategies were implemented to share research findings with residents and with local and national decision-makers.</p> <p>Partnership achievements and difficulties</p> <p>Using a mixed and interdisciplinary research approach was critical to grasping the complexity of this community-based process. The adoption of the process and the partnership with local decision-makers were very effective. Therefore, at the instigation of an NGO, four other districts in Burkina Faso and Niger reproduced this experiment. However, national decision-makers showed no interest in this action and still seem unconcerned about finding solutions that promote access to health care for the indigent.</p> <p>Lessons learned</p> <p>The lessons learned with regard to knowledge transfer and partnerships between researchers and associated decision-makers are: i) involve potential users of the research results from the research planning stage; ii) establish an ongoing partnership between researchers and users; iii) ensure that users can participate in certain research activities; iv) use a variety of strategies to disseminate results; and v) involve users in dissemination activities.</p

    Biomass cookstoves: A review of technical aspects and recent advances

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    The global increase in population coupled with poor access to clean energy has set pressure on solid fuel use. Through this, about one-third of the world's population currently relies on solid fuels (fuelwood, charcoal, coal, agro-residues, dung, etc.) in meeting their primary energy needs. However, only 11% of this population used improved biomass cookstoves (cookstoves with potential reductions in fuel use and toxic emissions). This is more peculiar to developing countries where cooking accounts for about 90% of domestic energy consumption. With this, research on cookstoves technology has increased in recent years as about 1905 articles have been reportedly published in less than a decade (2014–2022). This paper aims at bringing together literature spanning over a decade with a focus on the technical aspects of biomass cookstoves to establish the recent advances and current state of knowledge. Literature on different biomass cookstoves designs, operational features, and testing protocols have been reviewed. An overview of various cookstove performances was critically discussed with emphasis on thermal and emission performance. Having looked at the literature, pathways for future studies were recommended. This includes the incorporation of social factors such as end users’ perceptions in the design and development phase. This will not just enhance the design process but may influence the cookstove adoption. Others are developing similitudes of the traditional models but in improved forms using locally available materials, as well as models that operate with solid and liquid biofuels
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