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Staurotypus salvini
Number of Pages: 2Integrative BiologyGeological Science
Population Estimates and Geographic Distribution of the Yellow Mud Turtle (Kinosternon flavescens) in Iowa
The yellow mud turtle (Kinosternon flavescens) is an endangered species in Iowa known from six localities in the stare. The only large population is located on a private preserve on Big Sand Mound in Muscatine and Louisa Countries and is estimated to consist of 2,000 to 3,000 individuals. Following the removal of predators in 1979, density estimates have tripled as estimated by the Sequential Bayes Algorithm of mark-recapture data. Assuming the Big Sand Mound population was nor severely damaged by the drought of 1988, it is judged sufficiently large to serve as a source to enrich certain of Iowa\u27s other mud turtle populations
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
Acoustic breathers in two-dimensional lattices
The existence of breathers (time-periodic and spatially localized lattice
vibrations) is well established for i) systems without acoustic phonon branches
and ii) systems with acoustic phonons, but also with additional symmetries
preventing the occurence of strains (dc terms) in the breather solution. The
case of coexistence of strains and acoustic phonon branches is solved (for
simple models) only for one-dimensional lattices.
We calculate breather solutions for a two-dimensional lattice with one
acoustic phonon branch. We start from the easy-to-handle case of a system with
homogeneous (anharmonic) interaction potentials. We then easily continue the
zero-strain breather solution into the model sector with additional quadratic
and cubic potential terms with the help of a generalized Newton method. The
lattice size is . The breather continues to exist, but is dressed
with a strain field. In contrast to the ac breather components, which decay
exponentially in space, the strain field (which has dipole symmetry) should
decay like . On our rather small lattice we find an exponent
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
Evaluation of two doses of etoricoxib, a COX-2 selective non-steroidal anti-inflammatory drug (NSAID), in the treatment of Rheumatoid Arthritis in a double-blind, randomized controlled trial
List of Ethics Committees. (DOCX 38 kb
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