A Modified, Implicit, Directly Additive Demand System

A recently developed demand system, nicknamed AIDADS, offers a more general approach to capturing consumption preferences. AIDADS generalizes the LES by assuming marginal budget shares vary indirectly with expenditure. AIDADS is limited by the fact that the subsistence parameters are constant across expenditure. We modify AIDADS by replacing the constant subsistence parameters with a function which varies with utility, and hence expenditure. The modified AIDADS (MAIDADS) allows subsistence levels to vary with expenditure. This model is applied to the 1996 International Consumption Project data. As these data span a wide range of expenditure levels, MAIDADS offers a viable alternative when estimating "global demand systems." Results suggest subsistence values for livestock and other food products vary with expenditure, while those for grain are constant across expenditure.Demand and Price Analysis,

Does nitrate deposition following astrophysical ionizing radiation events pose an additional threat to amphibians?

It is known that amphibians are especially susceptible to the combination of heightened UVB radiation and increased nitrate concentrations. Various astrophysical events have been suggested as sources of ionizing radiation that could pose a threat to life on Earth, through destruction of the ozone layer and subsequent increase in UVB, followed by deposition of nitrate. In this study, we investigate whether the nitrate deposition following an ionizing event is sufficiently large to cause an additional stress beyond that of the heightened UVB previously considered. We have converted predicted nitrate depositions to concentration values, utilizing data from the New York State Department of Environmental Conservation Acid Rain Monitoring Network web site. Our results show that the increase in nitrate concentration in bodies of water following the most intense ionization event likely in the last billion years would not be sufficient to cause a serious additional stress on amphibian populations and may actually provide some benefit by acting as fertilizer.Comment: This version is a longer, more detailed draft of an article submitted to the journal Astrobiolog

IMPLICIT ADDITIVE PREFERENCES: A FURTHER GENERALIZATION OF THE CES

The CES is generalized by extension of the work of Hanoch (1975) resulting in implicit, direct and indirect relationships between utility and consumption. Expressions for substitution and income elasticities are developed and observed to be variable, rather than constant as in the CES case.Food Consumption/Nutrition/Food Safety,

Patient and Family Caregivers’ Experiences of Living With a Jejunostomy Feeding Tube After Surgery for Esophagogastric Cancer

BACKGROUND: Jejunostomy feeding tubes (JFTs) can be used to provide nutrition support to patients who have had surgery for esophagogastric cancer. Although previous research reports how patients cope with a gastrostomy tube, little is known about the impact of having a JFT. The aim of this qualitative study was to explore how patients and their informal caregivers experience living with a JFT in the first months following surgery. METHODS: Participants were purposively sampled from a cohort of patients recruited to a trial investigating home enteral nutrition vs standard care after esophagogastric surgery for cancer. The sampling framework considered age, sex, and marital status. Informal caregivers were also invited to participate. Interviews were audio recorded, transcribed verbatim, and anonymized. Inductive thematic analysis was used to identify key themes related to living with a JFT. RESULTS: Fifteen patient interviews were conducted; 8 also included a family caregiver. Analysis of the data resulted in 2 main themes: "challenges" and "facilitators" when living with a JFT. While "physical effects," "worries" and "impact on routine" were the main challenges, "support," "adaptation" and "perceived benefit" were what motivated continuation of the intervention. CONCLUSION: Findings suggest that participants coped well with a JFT, describing high levels of compliance with stoma care and the feeding regimen. Nonetheless, disturbed sleep patterns and stoma-related problems proved troublesome. A better understanding of these practical challenges, from the patient and family caregiver perspective, should guide healthcare teams in providing proactive support to avoid preventable problems

Global Nutrition Impacts of Rapid Economic Growth in China and India

Despite record global economic growth in past decade malnutrition remains a serious problem in many parts of the world. According to the United Nations Food and Agriculture Organization (FAO), about 800 million people (17% of the worlds population) remain malnourished. For these households at a subsistence level of income, changes in commodity market conditions, as may arise from changes in global economic growth and/or trade policy can have serious consequences for nutritional intake. Even a small decline in diet quality can have substantial adverse impacts on health status. On the other hand, a modest income boost, or lower food prices, could have extremely positive impacts. Previously, the links between changes in the global economy and nutritional outcomes have been explored by a relatively wide range of authors (e.g., Fang et al., 2006; Rosegrant et al., 2005). The goal of this paper is to offer modest extensions of this previous work in three directions. First of all, unlike many of the papers in the nutrition area, we seek to account for the behavioral response of low income households in the face of changing prices and incomes. Clearly when households are faced with a rise in the price of food products, they cannot afford to consume as much, ceteris paribus so consumption much adjust. The extent of this adjustment will depend on the change in real income and the Engel elasticities for each good. In addition, consumers are likely to substitute away from higher cost food items. All of these factors could have an adverse impact on nutritional attainment. By estimating and incorporating a demand system into our analysis, we are able to take these factors into account. In so doing, we draw on the work of Rimmer and Powell (1996) and Cranfield et al. (2003a; 2003b) in order to characterize consumer demands across the income spectrum. A second important extension embodied in this work relates to the impact of changes in factor earnings on household nutritional attainment in the wake of globalization. Most economic analyses of this issue have tended to focus on the commodity price impacts of globalization. If they have taken into account the earnings-side impacts, they have typically done so in a simplistic way. In this paper, we seek to capture the earnings-heterogeneity of poor households and thereby shed light on the differential impact of global economic growth on different household groups. We do so using the framework developed in Hertel et al. (2004), and further refined in Hertel et al. (2007a). The final contribution of this paper is to imbed this framework for analysis of nutritional issues into a widely used, global general equilibrium model (GTAP: Hertel, 1997) in order to permit nutritional outcomes to be routinely reported as part of standard economic analyses of global economic growth and trade liberalization. We illustrate this approach to the analysis of nutritional impacts of global economic growth through a series of globalization shocks, focusing on the impacts in Bangldesh. We begin by considering solely the impact of an exogenous rise in the consumer price rise for food products. This permits us to illustrate the mechanisms through which low income consumers respond to changing economic conditions in our framework. We then turn to an analysis of the impact of economic growth in India and China, respectively, on the poor in Bangladesh, and in particular on their nutritional attainment. Our findings indicate that the nutritional impacts of globalization depend importantly on the source of the globalization shock, and the resultant earnings effects on the poor.Food Consumption/Nutrition/Food Safety,

A mechanistic perspective on plastically flexible coordination polymers

Mechanical flexibility in single crystals of covalently bound materials is a fascinating and poorly understood phenomenon. We present here the first example of a plastically flexible one‐dimensional (1D) coordination polymer. The compound [Zn(μ‐Cl)2(3,5‐dichloropyridine)2]n is flexible over two crystallographic faces. Remarkably, the single crystal remains intact when bent to 180°. A combination of microscopy, diffraction, and spectroscopic studies have been used to probe the structural response of the crystal lattice to mechanical bending. Deformation of the covalent polymer chains does not appear to be responsible for the observed macroscopic bending. Instead, our results suggest that mechanical bending occurs by displacement of the coordination polymer chains. Based on experimental and theoretical evidence, we propose a new model for mechanical flexibility in 1D coordination polymers. Moreover, our calculations propose a cause of the different mechanical properties of this compound and a structurally similar elastic material

Gauged Fermionic Q-balls

We present a new model for a non-topological soliton (NTS) that contains interacting fermions, scalar particles and a gauge field. Using a variational approach, we estimate the energy of the localized configuration, showing that it can be the lowest energy state of the system for a wide range of parameters.Comment: 5 pages, 2 figures; revised version to appear in Phys. Rev.

Metabolic engineering of apple by overexpression of the MdMyb10 gene

Flavonoids are low-molecular-weight phenolic compounds that are widely distributed in the plant kingdom. They have different roles in plant resistance to biotic and abiotic stresses. The transcription factor gene MdMyb10 (Gene Bank: DQ267896) was introduced into two apple (Malus domestica Borkh.) cultivars i.e. ‘Holsteiner Cox (HC)’ and ‘Gala’ via Agrobacterium-mediated transformation. The regenerated shoots were selected on kanamycin containing media. The presence of additional MdMyb10 gene in putative shoots was confirmed by PCR, RT-PCR and Southern blotting. Expression level of introduced MdMyb10 gene was analyzed by quantitative real time PCR. The results confirmed a dramatic increase in overexpression of MdMyb10 in the transgenic plants, up to 1261 and 847-folds for cultivars Holsteiner Cox and Gala, respectively compared to non-transformed negative control plants. HPLC-MS was used to determine the levels of different flavonoid compounds in both non-transgenic and transgenic plants. In MdMyb10 ‘HC’ transgenic plants, some of the polyphenols analyzed were enhanced while others were reduced in comparison to their levels in the non-transgenic plants. On the other hand, all of the analyzed polyphenol classes were induced in MdMyb10 ‘Gala’ transgenic plants in comparison to their levels in the non-transgenic plants. In the present study, the flavonoid pathway was successfully modified in apple by overexpressing the MdMyb10 transcription factor to validate the hypothesis of increased effect on plant disease resistance.Islamic Development Ban

Magnetic ordering, electronic structure and magnetic anisotropy energy in the high-spin Mn10_{10} single molecule magnet

We report the electronic structure and magnetic ordering of the single molecule magnet [Mn$_{10}$O$_{4}$(2,2'-biphenoxide)$_{4}$Br$_{12}$]$^{4-}$ based on first-principles all-electron density-functional calculations. We find that two of the ten core Mn atoms are coupled antiferromagnetically to the remaining eight, resulting in a ferrimagnetic ground state with total spin S=13. The calculated magnetic anisotropy barrier is found to be 9 K in good agreement with experiment. The presence of the Br anions impact the electronic structure and therefore the magnetic properties of the 10 Mn atoms. However, the electric field due to the negative charges has no significant effect on the magnetic anisotropy.Comment: 4 pages, submitted to PR