3,109 research outputs found
THE POTENTIAL ROLE OF PRICE INSURANCE TO IMPROVE WELFARE OF HONDURAN COFFEE PRODUCERS
Coffee is the major export crop in Honduras, but the export price is relatively low. This paper investigates the potential role for a coffee price insurance product - based on the use of the coffee future market - to increasing producer welfare by reducing coffee price risk faced by individual farmers. By constructing a typology of six different types of coffee farmers and developing a forecasting model, the authors show that more risk-averse farmers would prefer to buy the insurance contract than those with lower risk aversion. The subjective assessments analysis also show that Honduran coffee producers have optimistic expectations for coffee prices and appear to underestimate the variability of coffee prices.Risk and Uncertainty,
Participation by men and women in off-farm activities: An empirical analysis in rural northern Ghana
"Using survey data from the Upper East region of Ghana collected in 2005, the paper evaluates the household- and community-level factors influencing women's and men's decisions to participate in off-farm activities, either in the off-farm labor market or in local community groups, and the relationship with on-farm crop returns. Results indicate that crop returns are not affected by increased labor availability over a certain labor-land ratio. Female participation in off-farm labor markets increases at higher levels of labor availability, but participation in women's groups' only increases as labor scarcity is relaxed at lower levels. Alternatively, male participation in off-farm work increases over all levels of labor availability. Results also indicate that male labor is relatively more productive on-farm versus off-farm than female labor, and, though education increases the likelihood that both women and men will work off-farm (with no impact on crop revenues), the impact is greater for women. Finally, participation in off-farm work does not appear to be driven by the need to reduce exposure to risk or to manage risk ex post; wealthier households located in wealthier communities are more likely to participate in off-farm work. Evidence for participation in groups and risk is more complicated; wealthier households in wealthier communities are also more likely to participate, but so too are female-headed households with higher dependency ratios." from authors' abstractOff-farm labor supply, Participation, Community groups, Gender, Land management, Poverty reduction,
Dust control for Enabler
The dust control group designed a system to restrict dust that is disturbed by the Enabler during its operation from interfering with astronaut or camera visibility. This design also considers the many different wheel positions made possible through the use of artinuation joints that provide the steering and wheel pitching for the Enabler. The system uses a combination of brushes and fenders to restrict the dust when the vehicle is moving in either direction and in a turn. This design also allows for each of maintenance as well as accessibility of the remainder of the vehicle
Barriers to e-Learning During Crisis: A Capital Theory Perspective on Academic Adversity
The unprecedented coronavirus pandemic (COVID-19) presented new, daunting academic adversities to college students, especially those from underserved communities. This study provides a nuanced understanding of underserved students’ adversities in online distance education, based on an in-depth analysis of narratives of 220 students from a minority-serving institution in the United States. Informed by the capital theory, the study revealed six major barriers to e-learning: technical, cultural, environmental, balance, social, and financial barriers, and identified new underlying dimensions. Moreover, the study found that technical barriers are often coupled with other types of barriers and underserved students are more likely to experience multiple learning barriers. A variance model of influencing factors was proposed for e-learning outcomes. The paper highlights new digital divide in e-learning and provides practical implications for educational institutions to support underserved students in overcoming academic adversities and building educational resilience
Two Factors that Bind to Highly Conserved Sequences in Mammalian Type C Retroviral Enhancers.
The transcriptional enhancers of the Moloney and Friend murine leukemia viruses (MLV) are important determinants of viral pathogenicity. We used electrophoretic mobility shift and methylation interference assays to study nuclear factors which bind to a region of these enhancers whose sequence is identical between Moloney and Friend viruses and particularly highly conserved among 35 mammalian type C retroviruses whose enhancer sequences have been aligned (E. Golemis, N. A. Speck, and N. Hopkins, J. Virol. 64:534-542, 1990). Previous studies identified sites for the leukemia virus factor b (LVb) and core proteins in this region (N. A. Speck and D. Baltimore, Mol. Cell. Biol. 7:1101-1110, 1987) as well as a site, overlapping those for LVb and core, for a third factor (N. R. Manley, M. A. O\u27Connell, P. A. Sharp, and N. Hopkins, J. Virol. 63:4210-4223, 1989). Surprisingly, the latter factor appeared to also bind two sites identified in the Friend MLV enhancer, Friend virus factor a and b1 (FVa and FVb1) sites, although the sequence basis for the ability of the protein to bind these diverse sites was not apparent. Here we describe the further characterization of this binding activity, termed MCREF-1 (for mammalian type C retrovirus enhancer factor 1), and the identification of a consensus sequence for its binding, GGN8GG. We also identify a factor, abundant in mouse T-cell lines and designated LVt, which binds to two sites in the Moloney MLV enhancer, overlapping the previously identified LVb and LVc binding sites. These sites contain the consensus binding site for the Ets family of proteins. We speculate on how distinct arrays of these factors may influence the disease-inducing phenotype
Performance of an IEEE 802.16 Wireless Backhaul in the Presence of a Node Failure
A wireless backhaul network is used to interconnect intermediate nodes to gateway nodes. As it is designed to serve a large population of broadband users, failure sustainability becomes an essential requirement to ensure uninterrupted telecommunication services even in the presence of occasional node or link failures. In this paper, the performance of a failure sustainable wireless backhaul, based on IEEE 802.16 radio technology, is analysed in the presence of a node failure. Furthermore, it is shown that the network performance is significantly improved by incorporating two proposed modifications, namely request-resend and dynamic mini-slot allocation, in IEEE 802.16 standard coordinated distributed scheduling
Failure Sustainable Wireless Backhaul
Backhaul network plays a significant role to interconnect access points and further connect them to gateway nodes. A failure sustainable wireless backhaul topology is proposed to ensure undisrupted telecommunication services even in the presence of occasional node or link failures. Furthermore, a new control message, called reverse notification, is proposed to improve the performance of coordinated distributed scheduling in the ladder topology. Computer simulation results show that the reverse notification scheme has improved the network throughput and reduced the packet transmission delay
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