4,593 research outputs found

    Interventions to slow aging in humans: Are we ready?

    Get PDF

    Depredation of Diamondback Terrapin (Malaclemys terrapin) Nests in North Inlet, SC: Nest Predator Community and the Cues Used by Raccoons to Locate Nests

    Get PDF
    Predation on diamondback terrapin eggs has been studied in several terrapin populations across their broad geographic range; however, nest predators have not been studied in South Carolina. Objectives of this project were two-fold: first, identify predators of diamondback terrapin eggs in North Inlet, SC; and second, determine the source of olfactory cue(s) used by raccoons to locate terrapin nests. Terrapin nest predators were identified using a combination of camera traps, visual surveys and trackboards. Raccoons were dominant nest predators and depredated 347 of 349 (combined natural and simulated) terrapin nests during the 2013 nesting season. We identified the source of the olfactory cue used by raccoons to locate nests through a series of experiments using simulated terrapin nests. Our results support the conclusion that foraging raccoons primarily utilize the scent of soil disinterred by nesting females, and not scent from the turtles themselves. Lastly, in our efforts to design scent cue experiments, we realized the need for an effective nest predator exclusion device. We conceived and tested a new design for predator exclusion cages that protected 70-100% of nests through three trials (n = 4, 8, 84)

    Insecticide use on vegetables in Ghana: Would GM seed benefit farmers?

    Get PDF
    "Tomato, cabbage, and garden egg (African eggplant, or Solanum aethiopicum) are important crops for small-scale farmers and migrants in the rural and peri-urban areas of Ghana. Genetic modification has the potential to alleviate poverty through combating yield losses from pests and diseases in these crops, while reducing health risks from application of hazardous chemicals. This ex ante study uses farm survey data to gauge the potential for adoption of genetically modified (GM) varieties, estimate the potential impact of adoption on farm profits, and highlight economic differences among the three crops. Farmers' expenditures on insecticides are below the economic optimum in all three crops, and the estimated function for damage abatement shows that insecticide amounts are significant determinants of cabbage yields only. Nonetheless, yield losses from pests and disease affect insecticide use. A stochastic budget analysis also indicates a higher rate of return to vegetable production with the use of resistant seeds relative to the status quo, even considering the technology transfer fee for GM seed. Non–insecticide users could accrue higher marginal benefits than current insecticide users. Comparing among vegetable crops with distinct economic characteristics provides a wider perspective on the potential impact of GM technology. Until now, GM eggplant is the only vegetable crop that has been analyzed in the peer-reviewed, applied economics literature. This is the first analysis that includes African eggplant." from authors' abstractBiotechnology Developing countries, Genetically modified crops, pesticides, Pests Management, eggplant, damage abatement, stochastic budget analysis,

    Cross-cultural comparison of the patient-centeredness of the hidden curriculum between a Saudi Arabian and 9 US medical schools

    Get PDF
    BACKGROUND: The implicit hidden curriculum strongly influences medical students\u27 perceptions of the importance of patient-centeredness. A new instrument, the Communication, Curriculum, and Culture Survey (C3), already used to assess this hard-to- access part of the curriculum in the US, has potential for use in cross-cultural comparisons. OBJECTIVE: To use the C3 to perform a pilot cross-cultural comparison of the patient-centeredness of the hidden curriculum between a Saudi medical school and 9 U.S. medical schools. DESIGN: Senior Saudi medical students completed the C3 and a second instrument, the Patient-Provider Orientation Scale (PPOS), which measured their attitudes toward patient-centered behavior. PARTICIPANTS: Senior Saudi medical students. RESULTS: 139/256 (54%) Saudis completed the C3; 122/256(48%) completed the PPOS. Means for 2 out of 3 of the C3\u27s domains (0-100 scale) were lower for the Saudis than those for the Americans (95% confidence intervals in parentheses): 47 (45, 50) vs. 55 (53, 58); 54 (50, 58) vs. 68 (67, 70); they overlapped in the third: 60 (57, 63) vs. 62 (60, 63). The mean Saudi PPOS score was 4.0 (3.9, 4.1); for the American medical schools, 4.8 (4.8-4.8) (1-6, least to most patient-centered). CONCLUSIONS: In this preliminary study the data suggest that the patient-centeredness of the hidden curriculum differs in Saudi and US medical schools in 2 out of 3 domains. Cross-cultural use of instruments such as the C3 can highlight such important differences and help educators evaluate their curriculum from an international, as well as a local perspective. Use of instruments across borders is a growing trend and an indicator of the increasing globalization of medical education

    Arab and Jewish Attitude: Toward a Palestinian State

    Get PDF
    This article deals with the attitudes of Arabs and Jews in Israel regarding a Palestinian state. These include their images of such a state, the costs and benefits perceived if a Palestinian state were established, and the fears and desires involved, including the desire to keep contact with the Palestinian population in the various life domains. The article will attempt to analyze the extent to which the attitudes toward the establishment of a Palestinian state and its likely character derive from a rational calculus of expected costs and benefits to one\u27s own group

    Vegetable Production and Pesticide Use in Ghana: Would GM Varieties Have an Impact at the Farm Level?

    Get PDF
    The objective of this study is to evaluate pesticide use as an important factor affecting potential adoption and farm level impact of genetically modified (GM) vegetable varieties in Ghana. Tomato is the most consumed vegetable and a food security crop. Cabbage is a vegetable of growing importance but limited cultivation and is produced in urban areas. Garden egg is a native African crop of wide consumption and importance for rural economies. Farm level information was collected in randomly selected sites in southern and central regions of Ghana. Partial budget analysis shows that investments in pesticides are rather low, especially for tomato and garden egg. Analysis of production using an abatement framework shows that insecticide amounts are significant in determining cabbage output levels only. Rate of returns of GM seeds however can still be high. GM varieties would need to show not only a high abatement rate and a high yield potential but mainly an affordable price, to reduce total costs and induce adoption.Farm, Genetically Modified, Ghana, Tomato, Agricultural and Food Policy, Consumer/Household Economics, Environmental Economics and Policy, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Health Economics and Policy, International Relations/Trade, Marketing, Productivity Analysis, Research and Development/Tech Change/Emerging Technologies,

    Insecticide Use on Vegetables in Ghana: Would GM Seed Benefit Farmers?

    Get PDF
    Tomato, cabbage and garden egg (African eggplant, or Solanum Aethiopicum) are important crops for small-scale farmers and migrants in the rural and peri-urban areas of Ghana. Genetic modification (GM) has the potential to alleviate poverty through combating yield losses from pests and diseases in these crops, while reducing health risks from application of hazardous chemicals. This ex-ante study uses farm survey data to gauge the potential for adoption of genetically-engineered varieties, estimate the potential impact of adoption on farm profits, and highlight economic differences among the three crops. Farmer's expenditures on insecticides are below the economic optimum in all three crops, and the estimated function for damage abatement shows that insecticide amounts are significant determinants of cabbage yields only. Nonetheless, yield losses from the pests and diseases affect insecticide use. Stochastic budget analysis also indicates a higher rate of return to vegetable production with the use of resistant seeds relative to status quo, even considering the technology transfer fee for GM seeds. Non-insecticide users could accrue higher marginal benefits than current insecticide users. Comparing among vegetable crops with distinct economic characteristics provides a wider perspective on the potential impact of GM technology. Until now, GM eggplant is the only vegetable crop that has been analyzed in the peer-reviewed, applied economics literature. This is the first analysis that includes African eggplant.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

    Experimental study to enhance swirl burner against boundary layer flashback

    Get PDF
    In gas turbine systems, operation stability represents the major challenge to any successful device deployment. Climate change combined with fossil fuel pollution has led to the need of considering high hydrogen content fuels, thus putting more pressure to stabilise gas turbines at operation conditions. Flashback is one of the main operation stability problems that represent a real challenge for gas turbine designers when using fast reacting fuels with high hydrogen content. One mechanism that has shown to contribute to flashback considerably is the propagation of the flame through its boundary layer. Although the latter has been studied, there are still several unknowns in its evolution through the system. Thus, boundary layer flashback of a swirling turbulent flame was investigated in a 150 kW tangential swirl burner previously characterised. To produce controlled changes to the boundary layer, the internal side of the burner was covered by woven wire steel mesh to mimic biological skin techniques in flow drag improvement. Two different wire meshes were used to study the effect of the regular roughness size on the boundary flashback. Moreover, the effects of using the wire mesh in such swirling flow with and without central air injection for reduction of other flashback phenomena were studied. The results show good enhancement of the system to boundary layer flashback, and a new map of the combustion stability of the rig has been produced
    corecore