Redefining Stewardship over Body Parts

This paper proposes one possible avenue for defining a framework to address body parts. I begin with the presumption that given the increasing use of body parts outside of our bodies, either after death or during life, society requires a framework with institutions and rules to govern our body parts. Yet there is no settled framework. Much of the controversy over differing approaches stems from whether people should be able to sell body parts. Thus, each potential framework implicitly addresses the question of monetary value. While multiple possibilities exist, the predominant models are (1) property, most often meaning ownership that permits monetary compensation; (2) stewardship, implying altruism and no monetary compensation to the donor; and (3) a compromise solution involving regulatory bodies, which could assign monetary value under certain circumstances

Selenium Bioconcentration in Freshwater Periphyton

Selenium is an essential micronutrient for most forms of life, but it can elicit developmental toxicity in aquatic and semi-aquatic vertebrates, such as fish and waterfowl, through dietary exposure to excess organic Se compounds. When inorganic Se (as selenate or selenite) is introduced into an aquatic ecosystem as a contaminant, it is bioconcentrated by microorganisms and primary producers (algae, periphyton), biotransformed into organic Se compounds and passed on to higher trophic levels through the food chain. The enrichment of Se in algae is difficult to predict due to interspecific differences in Se bioconcentration, which have been demonstrated to vary by several orders of magnitude in planktonic algae. In addition, Se bioconcentration data are largely lacking for freshwater, periphytic species of algae, and for multi-species periphyton biofilms, adding to the challenge of modeling Se transfer in periphyton-based food webs. Therefore, this research project was designed to address specific knowledge gaps related to the enrichment of selenium in different periphyton communities, as defined by differences in photoautrophic assemblage composition. To satisfy this objective, laboratory-grown and naturally-grown periphyton biofilms were exposed to environmentally relevant concentrations of selenite [Se(IV)] or selenate [Se(VI)] (nominal concentrations of 5 and 25 μg Se L-1) under similar, controlled laboratory conditions. Laboratory-grown periphyton biofilm experiments assessed Se oxyanion bioconcentration in single-species, freshwater periphytic biofilms representative of three major algal phyla: Chlorophyta (Stichococcus bacillaris), Cyanophyta (Anabaena flos-aquae) and Bacillariophyta (Asterionella formosa). Results of these experiments revealed that there was different enrichment of selenate versus selenite for the three species of algae tested (e.g., selenite enrichment was significantly higher than selenate enrichment for A. formosa). There were also significant differences in Se enrichment when comparing similar treatments among the three species of algae tested (e.g., enrichment of selenate was 3.6-fold higher in S. bacillaris compared to A. flos-aquae for the 25 μg Se L-1 treatment). Nevertheless, interspecific Se enrichment did not vary by orders of magnitude for freshwater periphyton, but rather by less than one order of magnitude. Naturally-grown periphyton experiments assessed Se oxyanion accumulation in freshwater periphyton communities sampled from five different water bodies. Results revealed that unique periphyton assemblages were derived from the five different field sites, as confirmed by light microscopy and targeted DNA sequencing of the plastid 23S rRNA gene in algae. Selenium accumulation demonstrated a maximum of 23.6-fold difference for selenite enrichment and 2.1-fold difference for selenate enrichment across the periphyton/biofilm assemblages tested. The assemblage from one field site demonstrated both high accumulation of selenite and iron, and was subjected to additional experimentation to elucidate the mechanism(s) of accumulation. Selenite accumulation was assessed in both unaltered and heat-killed periphyton, and in periphyton from the same site grown without light to exclude phototrophic organisms. All periphyton treatments showed similar levels of Se accumulation, indicating that much of the apparent uptake of selenite was due to non-biological processes (i.e., surface adsorption). The results of this study highlight the need for further exploration of the ecological consequences of extracellular adsorption of selenite to periphyton and will also help to reduce uncertainty in the prediction of Se dynamics and food-chain transfer in freshwater environments

The Estimation of Marginal Utility of Income for Application to Agricultural Policy Analysis

Exact date of working paper unknown

Factors Associated with Farm Household Poverty

A logit model is used to analyze factors associated with the incidence of poverty in Ohio farm households. This analysis suggests that the incidence of poverty is positively associated with financial risk, negatively associated with non-farm employment, household equity, and farm size, but not associated with participation in government programs

Factors Affecting Performance Measures in Northwestern Ohio Farms

Exact date of working paper unknown.Two performance measures, return on assets and overall efficiency, are calculated for a set of Ohio farms in the Lake Erie Basin in 1987, 1988, 1990 ,and 1992. These performance measures are analyzed to determine if they are affected by farming practices, capital structure, and farm operator characteristics. On average Ohio Farms in the Lake Erie Basin exhibit a 54 percent overall efficiency and a 5.25 percent return on assets for the four years studied. Farm size influences return on assets (ROA) and overall efficiency. Crop rotations and tillage practices have no statistical effects on ROA and overall efficiency

Proton radiation damage in bulk n-GaAs

Bulk samples of Te-doped n-type GaAs were irradiated using 10 MeV to 24 MeV protons to fluences between 2 x 10 to the 11th power protons/sq cm and 2 x 10 to the 14th power protons/sq cm. Majority carrier electrical effects were measured using the vanderPauw techniques and it was observed that radiation damage was minimal at the 10 to the 11th power proton/sq cm fluence. For the higher fluences, carrier removal was proportional to Delta E/Delta x for the protons indicating ionization interactions between the protons and atoms. Thermal annealing was observed at 155 C

Limitations in Predicting Radiation-Induced Pharmaceutical Instability during Long-Duration Spaceflight

As human spaceflight seeks to expand beyond low-Earth orbit, NASA and its international partners face numerous challenges related to ensuring the safety of their astronauts, including the need to provide a safe and effective pharmacy for long-duration spaceflight. Historical missions have relied upon frequent resupply of onboard pharmaceuticals; as a result, there has been little study into the effects of long-term exposure of pharmaceuticals to the space environment. Of particular concern are the long-term effects of space radiation on drug stability, especially as missions venture away from the protective proximity of the Earth. Here we highlight the risk of space radiation to pharmaceuticals during exploration spaceflight, identifying the limitations of current understanding. We further seek to identify ways in which these limitations could be addressed through dedicated research efforts aimed towards the rapid development of an effective pharmacy for future spaceflight endeavors.Comment: in press, Nature Microgravit