2,620 research outputs found
A latent class approach to investiating consumer demand for genetically modified staple food in a developing country: The case of GM bananas in uganda
Progression and Remediation Policies for At-Risk Nursing Students
The purpose of this independent project is to examine the efficacy of the implementation of progression and remediation policies in nursing students who are atrisk for failing the National Council Licensure Examination (NCLEX). Nursing educators can identify the at-risk student and determine which type of guidance would be appropriate to help them achieve success. Issues addressed consist of the severity of the nursing shortage, identifying what characteristics place a student at-risk, when and how to intervene by utilizing progression and remediation policies, and a review of five policies implemented in nursing schools in a tri-state area. An extensive review of 1 iterature forms the foundation of the project. This paper concludes with the expected implications for nursing and reconunendations for further research
Vegetable Production and Pesticide Use in Ghana: Would GM Varieties Have an Impact at the Farm Level?
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?
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,
Hydrodynamic interaction in quasi-two-dimensional suspensions
Confinement between two parallel surfaces is found, theoretically and
experimentally, to drastically affect the hydrodynamic interaction between
colloid particles, changing the sign of the coupling, its decay with distance
and its concentration dependence. In particular, we show that three-body
effects do not modify the coupling at large distances as would be expected from
hydrodynamic screening.Comment: 8 pages, 2 figure
The Effect of Corner Modes in the Initial Conditions of Cosmological Simulations
In view of future high-precision large-scale structure surveys, it is important to quantify the percent and subpercent level effects in cosmological N-body simulations from which theoretical predictions are drawn. One such effect involves deciding whether to zero all modes above the one-dimensional Nyquist frequency, the so-called “corner” modes, in the initial conditions. We investigate this effect by comparing power spectra, density distribution functions, halo mass functions, and halo profiles in simulations with and without these modes. For a simulation with a mass resolution of mp ~ 1011 -h M 1 , we find that at z > 6, the difference in the matter power spectrum is large at wavenumbers above ∼80% of kNy, reducing to below 2% at all scales by z ~ 3. Including corner modes results in a better match between low- and high-resolution simulations at wavenumbers around the Nyquist frequency of the low-resolution simulation, but the effect of the corner modes is smaller than the effect of particle discreteness. The differences in mass functions are 3% for the smallest halos at z = 6 for the mp ~ 1011 -h M 1 simulation, but we find no significant difference in the stacked profiles of well-resolved halos at z 6. Thus removing power at ∣k∣ > kNy in the initial conditions of cosmological simulations has a small effect on small scales and high redshifts, typically below a few percent
BEAMS: separating the wheat from the chaff in supernova analysis
We introduce Bayesian Estimation Applied to Multiple Species (BEAMS), an
algorithm designed to deal with parameter estimation when using contaminated
data. We present the algorithm and demonstrate how it works with the help of a
Gaussian simulation. We then apply it to supernova data from the Sloan Digital
Sky Survey (SDSS), showing how the resulting confidence contours of the
cosmological parameters shrink significantly.Comment: 23 pages, 9 figures. Chapter 4 in "Astrostatistical Challenges for
the New Astronomy" (Joseph M. Hilbe, ed., Springer, New York, forthcoming in
2012), the inaugural volume for the Springer Series in Astrostatistic
The Nordic Seas carbon budget: Sources, sinks, and uncertainties
A carbon budget for the Nordic Seas is derived by combining recent inorganic carbon data from the CARINA database with relevant volume transports. Values of organic carbon in the Nordic Seas' water masses, the amount of carbon input from river runoff, and the removal through sediment burial are taken from the literature. The largest source of carbon to the Nordic Seas is the Atlantic Water that enters the area across the Greenland-Scotland Ridge; this is in particular true for the anthropogenic CO2. The dense overflows into the deep North Atlantic are the main sinks of carbon from the Nordic Seas. The budget show that presently 12.3 ± 1.4 Gt C yr−1 is transported into the Nordic Seas and that 12.5 ± 0.9 Gt C yr−1 is transported out, resulting in a net advective carbon transport out of the Nordic Seas of 0.17 ± 0.06 Gt C yr−1. Taking storage into account, this implies a net air-to-sea CO2 transfer of 0.19 ± 0.06 Gt C yr−1 into the Nordic Seas. The horizontal transport of carbon through the Nordic Seas is thus approximately two orders of magnitude larger than the CO2 uptake from the atmosphere. No difference in CO2 uptake was found between 2002 and the preindustrial period, but the net advective export of carbon from the Nordic Seas is smaller at present due to the accumulation of anthropogenic CO2
Acylation of glucosaminyl phosphatidylinositol revisited. Palmitoyl-CoA dependent palmitoylation of the inositol residue of a synthetic dioctanoyl glucosaminyl phosphatidylinositol by hamster membranes permits efficient mannosylation of the glucosamine residue
Two critical steps in the assembly of yeast and mammalian glycosylphosphatidylinositol (GPI) anchor precursors are palmitoylation of the inositol residue and mannosylation of the glucosamine residue of the glucosaminyl phosphatidylinositol (GlcNα-PI) intermediate. Palmitoylation has been reported to be acyl-CoA dependent in yeast membranes (Costello, L. C., and Orlean, P. (1992) J. Biol. Chem. 267, 8599-8603) but strictly acyl- CoA independent in rodent membranes (Stevens, V. L., and Zhang, H. (1994) J. Biol. Chem. 269, 31397-31403), and thus poorly conserved. In addition, it was suggested that acylation must precede mannosylation in both yeast (Costello, L. C., and Orlean, P. (1992) J. Biol. Chem. 276, 8599-8603) and rodent (Urakaze, M., Kamitani, T., DeGasperi, R., Sugiyama, E., Chang, H.-M., Warren, C. D., and Yeh, E. T. H. (1992) J. Biol. Chem. 267, 6459-6462) cells because GlcNα-acyl-PI accumulates in vivo when mannosylation is blocked. However, GlcNα-acyl-PI accumulation would also be expected if mannosylation and acylation were independent of each other. These issues were addressed by the use of a synthetic dioctanoyl GlcNα-PI analogue (GlcNα-PI(C8)) as an in vitro substrate for GPI-synthesizing enzymes in Chinese hamster ovary cell membranes. GlcNα-PI(C8) was acylated in an manner requiring acyl-CoA. Thus, the process involving acyl-CoA reported for yeast has been conserved in mammals. Furthermore, both GlcNα-PI(C8) and GlcNα-acyl-PI(C8) could be mannosylated in vitro, but mannosylation of the latter was significantly more efficient. This provides direct support for the earlier suggestion that acylation precedes mannosylation in rodents cells. A similar result was also observed with the Saccharomyces cerevisiae mannosyltransferase. In contrast, it has been reported that mannosylation of endogenous GlcNα-PI by Trypansoma brucei membranes occurs without prior acylation. The same result was obtained with GlcNα-PI(C8), confirming that the mannosyltransferase of trypanosomes is divergent from those in yeasts and rodents
Security analysis for agroterrorism: applying the threat, vulnerability, consequence framework to developing countries
"We examine access to, use of, and participation in decisions on improved water supply in the Volta basin of Ghana, one of the first countries to introduce a community-based approach to rural water supply on a large scale. While 71 percent of the households interviewed have access to improved water, 43 percent of these continue to use unsafe sources as their main domestic water source. Our results indicate that quality perceptions and opportunity costs play an important role in households' choice of water source. The effect of prices and income levels on this choice differs according to the pricing system used. Given that supply characteristics such as the location and pricing system affect household decisions to use the improved source, households may try to influence these characteristics in their favor during the community decision-making process for the improved source. However, less than 40 percent of the households interviewed participated in decisions on location or technology. We argue that the decision whether to participate depends on three main factors: (i) the household's bargaining power, (ii) the potential benefits from influencing outcomes, and (iii) the cost of participation, (mainly opportunity cost of time). Our results indicate that bargaining power matters In some developing countries the potential exists for agroterrorism to cause widespread disruption through loss of sustenance, income and production. Defense of agriculture may also be problematic because of the lack stability and basic biosecurity infrastructure for the detection and prevention of diseases or invasive species. Currently new methodological approaches for terrorism risk assessments are being actively explored for resource prioritization. One such methodology for risk based allocation of resources is Threat, Vulnerability, and Consequence (TVC) Analysis. A qualitative application of the TVC framework is used to analyze the risk of agroterrorism in developing countries relative to industrialized countries. The analysis suggests that evidence exists to demonstrate general terrorist threats, vulnerability of agriculture and, depending on the country, potentially serious consequences arising from argoterrorism. Where specific threats emerge, action may be needed by the international community to strengthen biosecurity systems in developing countries through: increasing global cooperation, capacity building in monitoring, remediation and risk analysis technologies, and the dissemination of novel technologies for control of pests and diseases." Authors' AbstractCapacity strengthening, Water-supply Management, Agroterrorism, Biosecurity, Risk analysis, resource allocation, Terrorism, Governance,
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