48 research outputs found

    Agricultural extension for women farmers in Africa

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    Women are responsible for at least 70 percent of food staple production in Africa. They are also important in other agricultural activities, including food processing and marketing, cash cropping and animal husbandry. Women's involvement is significant not only in terms of their labor input, but also in terms of their decision-making authority. This paper proposes a series of operational guidelines on how to provide agricultural extension services in a cost-effective way to women farmers. All small-scale farmers, regardless of gender, face constraints, but the focus here is on women farmers in order to foster a better understanding of the particular gender-related barriers confronting women and the strategies needed to overcome them. Attention is concentrated on sub-Saharan Africa in view of the crucial role of women in agriculture throughout the sub-continent. This paper addresses the question of why women need help -- the role women have in agriculture and the particular constraints they face in terms of access to resources and information. It examines the information needed to modify extension systems to better reach women farmers, to modify the focus of research to address women's activities and to monitor and evaluate programs. The paper also deals with the transmission of the extension message to women farmers and the formulation of the message to be delivered, and the linkage between extension and agricultural research and technology.Agricultural Research,Health Monitoring&Evaluation,Crops&Crop Management Systems,Primary Education,Agricultural Knowledge&Information Systems

    A cognitive pathway to punishment insensitivity

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    Individuals differ in their sensitivity to the adverse consequences of their actions, leading some to persist in maladaptive behaviors. Two pathways have been identified for this insensitivity: a motivational pathway based on excessive reward valuation and a behavioral pathway based on autonomous stimulus–response mechanisms. Here, we identify a third, cognitive pathway based on differences in punishment knowledge and use of that knowledge to suppress behavior. We show that distinct phenotypes of punishment sensitivity emerge from differences in what people learn about their actions. Exposed to identical punishment contingencies, some people (sensitive phenotype) form correct causal beliefs that they use to guide their behavior, successfully obtaining rewards and avoiding punishment, whereas others form incorrect but internally coherent causal beliefs that lead them to earn punishment they do not like. Incorrect causal beliefs were not inherently problematic because we show that many individuals benefit from information about why they are being punished, revaluing their actions and changing their behavior to avoid further punishment (unaware phenotype). However, one condition where incorrect causal beliefs were problematic was when punishment is infrequent. Under this condition, more individuals show punishment insensitivity and detrimental patterns of behavior that resist experience and information-driven updating, even when punishment is severe (compulsive phenotype). For these individuals, rare punishment acted as a “trap,” inoculating maladaptive behavioral preferences against cognitive and behavioral updating

    Can Life develop in the expanded habitable zones around Red Giant Stars?

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    We present some new ideas about the possibility of life developing around sub-giant and red giant stars. Our study concerns the temporal evolution of the habitable zone. The distance between the star and the habitable zone, as well as its width, increases with time as a consequence of stellar evolution. The habitable zone moves outward after the star leaves the main sequence, sweeping a wider range of distances from the star until the star reaches the tip of the asymptotic giant branch. If life could form and evolve over time intervals from 5×1085 \times 10^8 to 10910^9 years, then there could be habitable planets with life around red giant stars. For a 1 M⊙_{\odot} star at the first stages of its post main-sequence evolution, the temporal transit of the habitable zone is estimated to be of several 109^9 years at 2 AU and around 108^8 years at 9 AU. Under these circumstances life could develop at distances in the range 2-9 AU in the environment of sub-giant or giant stars and in the far distant future in the environment of our own Solar System. After a star completes its first ascent along the Red Giant Branch and the He flash takes place, there is an additional stable period of quiescent He core burning during which there is another opportunity for life to develop. For a 1 M⊙_{\odot} star there is an additional 10910^9 years with a stable habitable zone in the region from 7 to 22 AU. Space astronomy missions, such as proposed for the Terrestrial Planet Finder (TPF) and Darwin should also consider the environments of sub-giants and red giant stars as potentially interesting sites for understanding the development of life
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