Burst annealing of high temperature GaAs solar cells

One of the major limitations of solar cells in space power systems is their vulnerability to radiation damage. One solution to this problem is to periodically heat the cells to anneal the radiation damage. Annealing was demonstrated with silicon cells. The obstacle to annealing of GaAs cells was their susceptibility to thermal damage at the temperatures required to completely anneal the radiation damage. GaAs cells with high temperature contacts and encapsulation were developed. The cells tested are designed for concentrator use at 30 suns AMO. The circular active area is 2.5 mm in diameter for an area of 0.05 sq cm. Typical one sun AMO efficiency of these cells is over 18 percent. The cells were demonstrated to be resistant to damage after thermal excursions in excess of 600 C. This high temperature tolerance should allow these cells to survive the annealing of radiation damage. A limited set of experiments were devised to investigate the feasibility of annealing these high temperature cells. The effect of repeated cycles of electron and proton irradiation was tested. The damage mechanisms were analyzed. Limitations in annealing recovery suggested improvements in cell design for more complete recovery. These preliminary experiments also indicate the need for further study to isolate damage mechanisms. The primary objective of the experiments was to demonstrate and quantify the annealing behavior of high temperature GaAs cells. Secondary objectives were to measure the radiation degradation and to determine the effect of repeated irradiation and anneal cycles

The avifauna of Bishop and Clerk islets and its relationship to nearby Macquarie Island

A first comprehensive survey of seabirds at Bishop and Clerk islets conducted on 23 December 1993 recorded a total of 12 species. During a three-hour-long visit by helicopter, nine species were found breeding, mostly in nests on the ground, but also in burrows dug in shallow soil. These included the largest known colony of Black-browed Albatross, Thalassarche melanophris, in Australia. Ten bird species are now known to breed at the islets. Specics accounts are given including data on morphometries, abundance, habitats, breeding, threats, interspecific competition for space and unpublished information

Career Longevity of Hospitality Graduates

A survey of hospitality alumni from two- and four-year programs, including those currently employed in the industry and those who have departed from the industry shows that within five years of graduation, 38 percent of hospitality graduates have left employment in the hospitality industry or chose to never enter the industry for which they trained. Factors affecting the graduates\u27 career Longevity their likes and dislikes about employment, and their reasons for continuing employment or exiting were examined

Relationship Between 25(OH) Vitamin D3 and Cerebral Vascular Reactivity in College-aged African and Caucasian Americans

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Attenuated Cerebral Vasodilatory Capacity in Response to Hypercapnia in Young Obese Individuals

Obese individuals are at a greater risk for the development of a variety of cardio and cerebral vascular diseases including hypertension, atherosclerosis, coronary artery disease and stroke. Furthermore, obesity is associated with cognitive impairment and is a risk factor for dementia and Alzheimer’s disease. The exact mechanisms of this elevated risk are not fully characterized; however, impaired microvascular function is believed to be a contributor. This study tested the hypothesis that the cerebral vasodilatory capacity in response to hypercapnia is reduced in obese individuals relative to age and sex matched lean counterparts. Cerebral blood velocity (CBFV) was measured using transcranial Doppler before and during rebreathing-induced hypercapnia in obese (Obese, n=14) and lean (Lean, n=14) subjects. Cerebral vascular conductance (CVCI) was calculated as CBFV / mean arterial pressure (MAP), and a four parameter logistic regression was applied for sigmoidal curve fitting of the relationship between % change in CVCI and end-tidal CO2 tension (PETCO2). The magnitude of hypercapnia (Δ PETCO2) during rebreathing was similar between groups (Obese 14 ± 3 mmHg vs. Lean: 15 ± 2 mmHg; P = 0.13). The maximum increase in CVCI (Obese: 155 ± 17% vs. Lean: 176 ± 23%; P \u3c 0.05) and the total range of change in CVCI (Obese: 50 ± 15% vs. Lean: 75 ± 22%; P \u3c 0.01) during rebreathing were reduced in the obese relative to the lean individuals. These data indicate that cerebral vasodilatory capacity in response to changes in PETCO2 during hypercapnia is attenuated in obese individuals compared with lean individuals

Genetic Variation and Antioxidant Response Gene Expression in the Bronchial Airway Epithelium of Smokers at Risk for Lung Cancer

Prior microarray studies of smokers at high risk for lung cancer have demonstrated that heterogeneity in bronchial airway epithelial cell gene expression response to smoking can serve as an early diagnostic biomarker for lung cancer. As a first step in applying functional genomic analysis to population studies, we have examined the relationship between gene expression variation and genetic variation in a central molecular pathway (NRF2-mediated antioxidant response) associated with smoking exposure and lung cancer. We assessed global gene expression in histologically normal airway epithelial cells obtained at bronchoscopy from smokers who developed lung cancer (SC, n=20), smokers without lung cancer (SNC, n=24), and never smokers (NS, n=8). Functional enrichment analysis showed that the NRF2-mediated, antioxidant response element (ARE)-regulated genes, were significantly lower in SC, when compared with expression levels in SNC. Importantly, we found that the expression of MAFG (a binding partner of NRF2) was correlated with the expression of ARE genes, suggesting MAFG levels may limit target gene induction. Bioinformatically we identified single nucleotide polymorphisms (SNPs) in putative ARE genes and to test the impact of genetic variation, we genotyped these putative regulatory SNPs and other tag SNPs in selected NRF2 pathway genes. Sequencing MAFG locus, we identified 30 novel SNPs and two were associated with either gene expression or lung cancer status among smokers. This work demonstrates an analysis approach that integrates bioinformatics pathway and transcription factor binding site analysis with genotype, gene expression and disease status to identify SNPs that may be associated with individual differences in gene expression and/or cancer status in smokers. These polymorphisms might ultimately contribute to lung cancer risk via their effect on the airway gene expression response to tobacco-smoke exposure.Intramural Research Program of the National Institute of Environmental Health Sciences; National Institutes of Health (Z01 ES100475, U01ES016035, R01CA124640

Measured Sensitivity of the First Mark II Phased Array Feed on an ASKAP Antenna

This paper presents the measured sensitivity of CSIRO's first Mk. II phased array feed (PAF) on an ASKAP antenna. The Mk. II achieves a minimum system-temperature-over-efficiency $T_\mathrm{sys}/\eta$ of 78 K at 1.23 GHz and is 95 K or better from 835 MHz to 1.8 GHz. This PAF was designed for the Australian SKA Pathfinder telescope to demonstrate fast astronomical surveys with a wide field of view for the Square Kilometre Array (SKA).Comment: 5 pages, 2 figures, accepted for publication in Electromagnetics in Advanced applications (ICEAA), 2015 International Conference o

Role Strains and Mood in Husbands of Women with Fibromyalgia Syndrome: A Test of the Stress Process Model

Spouses of patients experience role strains as a result of informal caregiving, which has been associated with mood in numerous research studies. However, most research is on female caregivers, and little is known about the experience of male spouses, or of the caregiving provided to fibromyalgia patients. The Stress Process Model was used to examine mediators and moderators of the relation between role strain and mood among 135 husbands of women with fibromyalgia. Results indicated that the more activities of daily living and instrumental activities of daily living performed by the husband, the greater the role strain. Role strain was associated with worse mood. A test of the Stress Process Model supported a partial mediation model, where social support and emotion-focused coping partially mediated the relation between role strain and mood. No evidence was found for a moderation model or for problem-focused coping as a mediator. Our research suggests significant impairment and caregiving needs among this patient population, which in turn relates to the mood of the husband who is also an informal caregiver. Our findings also support the Stress Process Model in explaining the complexity of caregiving effects. The results of the study suggest avenues for intervention for individuals strained by their partners’ illness

Radio Frequency Identification: Legal Aspects

Radio frequency identification (RFID) is a wireless technology that identifies objects without having either contact or sight of them. Unlike optically read technologies such bar codes, RFID tags can be read despite fog, ice, snow, paint or widely fluctuating temperatures. Additionally, RFID can identify moving objects. Data in an RFID tag is stored in an integrated circuit, and sent to the reader via an antenna. An RFID reader is essentially a radio frequency receiver controlled by a microprocessor or digital signal processor. The reader uses an attached antenna to capture the data transmitted from the tag and sends the information to a computer, where the data is processed

Comparing Species of Bees for Controlled Pollination of Helianthus petiolaris in Field Cages

Honey bees, Apis mellifera, have been used for several years to pollinate caged plant species maintained at the USDA-ARS North Central Regional Plant Introduction Station (NCRPIS), Ames, Iowa. Because maintaining large numbers of honey bees is expensive and time consuming, we began looking in 1995 for other pollinator species that can be easily managed and less expensive to maintain than A. mellifera. One species we tested was the hornfaced bee, Osmia cornifrons, a solitary bee imported from Japan in the late 1970s. We also tested a mixture of native bumblebees, Bombus bimaculatus and B. impatiens, which are native to the U.S. Midwest. These bee species were compared in field cages to determine which would produce the greatest number of seeds/plant on the wild annual sunflower, Helianthus petiolaris. After 2 years testing, honey bees consistently produced more seeds/plant than did the other bees tested