Addison\u27s Disease in Half-Siblings

In this only reported incidence of Addison\u27s disease in half-siblings, the adrenal failure is postulated to be a sex-linked recessive character. Adrenocortical antibodies were not detected

Paper Session I-B - Passive Radiation Dosimetry on STS-91 Using DNA: Initial Results from ASPR-GRaDEx-1

Quantifying the radiation dosage and damage to biological systems, especially to humans during repetitive high altitude flight and during long duration space flight is important for several reasons. Radiation can cause altered biosynthesis and long term genotoxicity resulting in cancer and birth defects etc. Radiation damage to biological systems depends in a complex way on incident radiation species and their energy spectra. TY.pically non-biological, i.e. film or electronic monitoring systems with narrow energy band sensitivity are used for dosimetry and then results are extrapolated to biological models. For this reason it may be desirable to perform radiation dosimetry by using biological molecules e.g. DNA or RNA strands as passive sensors. The Association of Small Payload Researchers in conjunction with Texas A&M University and Broward Community College have constructed a genotoxicology experiment to determine the degree to which in-vitro naked DNA extracted from tissues of a variety of vertebrate organisms including man, chicken, and fish, is damaged by exposure to cosmic radiation in a space environment. The DNA is assayed by means of agarose gel electrophoresis to determine the average length of DNA strands in each sample. It is hoped that a low mass low cost passive biological system to determine dose-response relationship (increase in strand breaks with increase in exposure) can be developed to perform radiation dosimetry in support of long duration space flight, and to predict negative effects on biological systems (e.g. astronauts and greenhouses) in space. Initial results of a genotoxicology and radiation dosimetry experiment (ASPR-GRaDEx-1) are presented. The payload orbited on the space shuttle Discovery (STS-91) in June of 1998. The study has been supported by the Florida Space Institute, NASA, ASPR, the Department of Wildlife and Fisheries Sciences at Texas A&M University, Boeing-KSC, the National Space Biomedical Research Institute, the Florida Space Grant Consortium, Broward and Brevard Community Colleges, the University of Miami, and Belen Jesuit High School

THE EFFECT OF REACHING TO AN OVERHEAD GOAL WHILE PERFORMING THE COUNTERMOVEMENT JUMP

One potentially simple way to maximize jumping effort and thus intensity is to have athletes jump to and attempt to touch challenging overhead goals during training. The purpose of this study was to compare the effect of jumping with and without the use of an overhead goal. Subjects performed 3 countermovement jumps in conditions with and without an overhead goal. Jump performance was evaluated using a force platform to determine peak ground reaction force, time to takeoff, power, and jump height. Data were evaluated with a two way ANOVA with results demonstrating no significant (p > 0.05) difference between goal conditions for any of the variables assessed and no interaction between goal condition and gender (p > 0.05)

KINETIC ANALYSIS OF SEVERAL VARIATIONS OF PUSH-UPS

Push-ups are a common and practical exercise though the kinetic characteristics of this exercise and its variations have yet to be quantified. This study assessed the peak ground reaction forces (GRF) of push-up variations including the regular push-up and those performed with bent knee, feet elevated on a 30.48 cm box and a 60.96 cm box, hands elevated on a 30.48 cm box and a 60.96 cm box. Peak GRF and peak GRF expressed as a coefficient of subject body mass were obtained with a force platform. Push-ups with the feet elevated produced higher GRF than all other push-up variations (p ≤ 0.05). Push-ups with hands elevated and from the bent knee position produced lower GRF than all other push-up variations (p ≤ 0.05). These data can be used to progress the intensity of push-ups in a program with loads that are quantified as a percentage of body mass

Contrasting patterns of genetic diversity at three different genetic markers in a marine mammal metapopulation

Many studies use genetic markers to explore population structure and variability within species. However, only a minority use more than one type of marker and, despite increasing evidence of a link between heterozygosity and individual fitness, few ask whether diversity correlates with population trajectory. To address these issues, we analyzed data from the Steller’s sea lion, Eumetiopias jubatus, where three stocks are distributed over a vast geographical range and where both genetic samples and detailed demographic data have been collected from many diverse breeding colonies. To previously published mitochondrial DNA(mtDNA) and microsatellite data sets,we have added new data for amplified fragment length polymorphism (AFLP) markers, comprising 238 loci scored in 285 sea lions sampled from 23 natal rookeries. Genotypic diversity was low relative to most vertebrates, with only 37 loci (15.5%) being polymorphic. Moreover, contrasting geographical patterns of genetic diversity were found at the three markers, with Nei’s gene diversity tending to be higher for AFLPs and microsatellites in rookeries of the western and Asian stocks, while the highest mtDNA values were found in the eastern stock. Overall, and despite strongly contrasting demographic histories, after applying phylogenetic correction we found little correlation between genetic diversity and either colony size or demography. In contrast, we were able to show a highly significant positive relationship between AFLP diversity and current population size across a range of pinniped species, even though equivalent analyses did not reveal significant trends for either microsatellites or mtDNA

Theory of sound attenuation in glasses: The role of thermal vibrations

Sound attenuation and internal friction coefficients are calculated for a realistic model of amorphous silicon. It is found that, contrary to previous views, thermal vibrations can induce sound attenuation at ultrasonic and hypersonic frequencies that is of the same order or even larger than in crystals. The reason is the internal-strain induced anomalously large Gr\"uneisen parameters of the low-frequency resonant modes.Comment: 8 pages, 3 figures; to appear in PR

Scholar-activists in an expanding European food sovereignty movement

This article analyzes the roles, relations, and positions of scholar-activists in the European food sovereignty movement. In doing so, we document, make visible and question the political dimensions of researchers' participation in the movement. We argue that scholar-activists are part of the movement, but are distinct from the affected constituencies, put in place to ensure adequate representation of key movement actors. This is because scholar-activists lack a collective identity, have no processes to formulate collective demands, and no mechanisms for inter-researcher and researchers-movement communication. We reflect on whether and how scholar-activists could organize, and discuss possible pathways for a more cohesive and stronger researcher engagement in the movement.</p

Population Genetics of Bowhead Whales (Baleana mysticetus) in the Western Arctic

Bowhead whales (Balaena mysticetus) in the Bering, Chukchi, and Beaufort seas experienced a severe reduction as a result of commercial whaling in the 19th century. Since the cessation of commercial whaling, the population has recovered to a size that is approaching pre-whaling estimates. Inupiat and Yupik communities in northern and western Alaska hunt these Western Arctic (WA) bowheads along their migratory path during spring and fall. This hunting is regulated by the International Whaling Commission. Recent but preliminary analysis of available genetic data (207 whales and 10 microsatellite markers) raised the question of the presence of multiple, genetically distinct populations within the WA bowheads. Here we re-examined this question on the basis of a study of 414 whales and 22 newly developed microsatellite loci. We identified widespread departures from Hardy-Weinberg equilibrium; however, we were unable to detect significant evidence of multiple genetic populations within the WA bowheads that could explain this Hardy-Weinberg disequilibrium, particularly when compared to the strength of evidence for differentiation between WA bowheads and other populations from distant regions such as the Okhotsk Sea and eastern Canada. There was conclusive evidence of genetic differentiation among the three regions. The statistical rejection of panmixia within the WA improves our understanding of bowhead whale biology, and the lack of evidence for multiple populations within the WA enables risk-averse management of aboriginal hunting of Western Arctic bowhead whales.La population de baleines boréales (Balaena mysticetus) des mers de Béring, de Tchoukotka et de Beaufort a enregistré un grave déclin en raison de la pêche commerciale à la baleine au XIXe siècle. Depuis que la pêche commerciale à la baleine a cessé, la population de baleines boréales a connu un certain essor au point où elle approche maintenant les estimations de la taille qu’elle avait avant la pêche commerciale à la baleine. Les collectivités Inupiat et Yupik du nord et de l’ouest de l’Alaska chassent les baleines boréales de l’ouest de l’Arctique le long de leur voie de migration au printemps et à l’automne. La chasse est réglementée par l’International Whaling Commission. Des analyses récentes, bien que préliminaires, des données génétiques disponibles (207 baleines et 10 marqueurs microsatellites) ont soulevé la question de la présence de multiples populations génétiquement distinctes au sein de la population de baleines boréales de l’ouest de l’Alaska. Ici, nous avons réexaminé cette question en fonction de l’étude de 414 baleines et de 22 locis microsatellites nouvellement mis au point. Nous avons remarqué d’importantes déviations de l’équilibre de Hardy-Weinberg; toutefois, nous n’avons pas pu trouver de preuve significative de populations génétiques multiples au sein des baleines boréales de l’ouest de l’Alaska qui pourrait expliquer ce déséquilibre de Hardy-Weinberg, plus particulièrement en comparaison avec la force de la preuve de différenciation entre les baleines boréales de l’ouest de l’Arctique et d’autres populations de régions distantes telles que la mer d’Okhotsk et l’est du Canada. Il y avait des preuves concluantes de différenciation génétique entre les trois régions. Le rejet statistique de la panmixie au sein de l’ouest de l’Arctique améliore notre compréhension de la biologie des baleines boréales, et le manque de preuves de populations multiples dans l’ouest de l’Arctique donne lieu à la gestion de l’aversion au risque de la chasse à la baleine boréale de l’ouest de l’Arctique par les Autochtones

The transcriptome of the bowhead whale Balaena mysticetus reveals adaptations of the longest-lived mammal

Mammals vary dramatically in lifespan, by at least two-orders of magnitude, but the molecular basis for this difference remains largely unknown. The bowhead whale Balaena mysticetus is the longest-lived mammal known, with an estimated maximal lifespan in excess of two hundred years. It is also one of the two largest animals and the most cold-adapted baleen whale species. Here, we report the first genome-wide gene expression analyses of the bowhead whale, based on the de novo assembly of its transcriptome. Bowhead whale or cetacean-specific changes in gene expression were identified in the liver, kidney and heart, and complemented with analyses of positively selected genes. Changes associated with altered insulin signaling and other gene expression patterns could help explain the remarkable longevity of bowhead whales as well as their adaptation to a lipid-rich diet. The data also reveal parallels in candidate longevity adaptations of the bowhead whale, naked mole rat and Brandt's bat. The bowhead whale transcriptome is a valuable resource for the study of this remarkable animal, including the evolution of longevity and its important correlates such as resistance to cancer and other diseases