10,627 research outputs found

    Notes on the Reproductive Biology of the Alabama Red Hills Salamander (Phaeognathus hubrichti )

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    Living Amphibia exhibit two major life history modes, possession of an aquatic larval stage or direct development, with the latter assumed to be the derived evolutionary condition (Duellman and Trueb 1986, Wake 1989). A small group (n = 20 species) of plethodontid salamanders, the subfamily Desmognathinae, is of great interest because its members display both developmental modes (Marks 1995). For decades the prevailing phylogenetic hypothesis for the group, based upon morphology and habitat, was a monophyletic sequence from the larger, more aquatic species that possessed the longest larval lives to two dwarf terrestrial species with direct development Dunn (1926). This “aquatic to terrestrial” hypothesis remained unchallenged even with the discovery of a new, giant, fossorial species, the Alabama Red Hills Salamander (Phaeognathus hubrichti), that was thought to be a third species with direct development (Highton 1961).Recently, analysis of mtDNA sequences revealed that the terrestrial desmognathines form the three deepest branches in desmognathine phylogeny, compelling the authors to advance an alternative phylogenetic hypothesis that absence of an aquatic larval stage may be ancestral for desmognathines (Titus and Larsen 1996). Their hypothesis rested, however, on details of the developing embryo and hatchlings in the three species with direct development, but critical data on the eggs, hatchlings, and whether larvae exist in P. hubrichti are unavailable.Aspects of the reproductive biology of the rare and secretive Phaeognathus hubrichti are difficult to observe in the field because the species is a burrower. One clutch laid by a female kept in captivity for six years apparently was unfertilized because the eggs failed to develop (Brandon and Moruska 1982). The large size and small number of ripe ovarian oocytes observed in preserved specimens, coupled with the unusual terrestrial burrowing behavior of the species, suggest the absence of an aquatic larval stage (Brandon 1965).On several visits to one ravine in Butler Co., Alabama (31°32’N, 86°45’W) during the spring and summer of 2002, I repeatedly observed a 105 mm SVL gravid female, discovered her eggs, kept them in captivity until they hatched, then returned the female and her clutch alive back into the field. Here I describe the field observations, eggs, embryos, and hatchlings

    Does macronutrient consumption affect aerobic capacity?

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    Background: Fitness in the United States is declining as the prevalence of obesity rises. It is known generally that exercise and diet both play a part in becoming fit, therefore veering away from being obese and/or overweight. Although people are aware they need to eat healthy foods and participate in physical activity, the role that dietary behaviors have on exercise, particularly aerobic capacity, remains unresolved. Purpose: The purpose of this study was to analyze dietary behaviors and to examine associations with maximal aerobic capacity. We hypothesize that those who consume each food group will have a higher volume of oxygen uptake. Methodology: This cross-sectional study consisted of a convenience sample of students, faculty, and staff (at least 18 years and older) that visited the Exercise Science Research Center as part of the larger Exercise is Medicine project. Participants completed a treadmill maximal oxygen uptake test to determine their VO2 max and were administered a 24-hour diet recall. In addition, they completed an online survey on dietary behaviors. Preliminary analyses examined associations between dietary patterns from the online survey and aerobic capacity. Linear regressions were used to test the associations between dietary behaviors (independent variable) and aerobic capacity (dependent variable) and were adjusted for sex and age. Results: There were a total of 47 participants (n=29 women) to date who have participated, with a mean age of 29.2 (SD 12.5, range 19.1 to 66.0). The average aerobic capacity of women was 36.6 ml/kg/min (SD 8.0), ranging from 15.2 to 51.8. The average aerobic capacity of men was 43.4 ml/kg/min (SD 6.8), ranging from 33.1 to 55.1. Aerobic capacity did not differ between those who drank milk daily vs those who did not (β -2.7, p=.350), those who ate fruit daily (β -.06, p=.798), ate whole grains at least 3 times per week (-2.9, p=.257), ate red meat at least 3 days per week (β -0.4, p=.844), or those who never ate dessert (β -7.1, p=.098). Discussion: There were no significant differences in VO2 max scores between those who consumed milk, fruit, whole grains, red meat, and dessert versus those that did not. This is likely because aerobic capacity is altered from performing exercise, rather than eating certain food groups. Although dietary behaviors are not associated with aerobic capacity, the evaluation of macronutrients compared to aerobic capacity will be examined as a part of this study. In the future, studies should include an analysis of both energy consumption and exercise participation to improve health and fitness outcomes

    NCAA FBI Probe

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    The article discusses the FBI probe as well as a list of other scandals that have risen from the investigation such as the debate as to whether to pay student athletes, the NCAA\u27s aim to stress academics over athletics, the NCAA\u27s transfer rules, and the one-and-done rule. The article also emphasizes the lack of emphasis on female athletes in the media and unfair treatment in relationship to Title XI

    BIOGEOGRAPHY AND PATTERN VARIATION OF KINGSNAKES, LAMPROPELTIS GETULA, IN THE APALACHICOLA REGION OF FLORIDA

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    Morphology of kingsnakes, Lampropeltis getula, is described and analyzed in the Apalachicola region of the Florida panhandle. Populations inhabiting the eastern Apalachicola Lowlands, a distinct biotic province, are different from the surrounding populations in having fewer and wider light body crossbands, distinct ontogenetic interband lightening, unique ventral patterns, and the presence of non-banded (striped and patternless) individuals. We conclude that the name L. g. goini as well as the hypothesis that Apalachicola L. getula are relict populations of intergrades between L. g. getula and L. g. floridana are invalid. We believe the polymorphic eastern Apalachicola Lowlands populations are most closely related to L. g. getula, and evolved in isolation on a barrier island or the coastal strand of a peninsula during one of the many higher stands of sea in the Pleistocene

    Cleavage of the apoptosis inhibitor DIAP1 by the apical caspase DRONC in both normal and apoptotic drosophila cells

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    In Drosophila S2 cells, the apical caspase DRONC undergoes a low level of spontaneous autoprocessing. Unintended apoptosis is prevented by the inhibitor of apoptosis DIAP1, which targets the processed form of DRONC for degradation through its E3 ubiquitin protein ligase activity. Recent reports have demonstrated that shortly after the initiation of apoptosis in S2 cells, DIAP1 is cleaved following aspartate residue Asp-20 by the effector caspase DrICE. Here we report a novel caspase-mediated cleavage of DIAP1 in S2 cells. In both living and dying S2 cells, DIAP1 is cleaved by DRONC after glutamate residue Glu-205, located between the first and second BIR domains. The mutation of Glu-205 prevented the interaction of DIAP1 and processed DRONC but had no effect on the interaction with full-length DRONC. The mutation of Glu-205 also had a negative effect on the ability of overexpressed DIAP1 to prevent apoptosis stimulated by the proapoptotic protein Reaper or by UV light. These results expand our knowledge of the events that occur in the Drosophila apoptosome prior to and after receiving an apoptotic signal

    Triaxial digital fluxgate magnetometer for NASA applications explorer mission: Results of tests of critical elements

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    Tests performed to prove the critical elements of the triaxial digital fluxgate magnetometer design were described. A method for improving the linearity of the analog to digital converter portion of the instrument was studied in detail. A sawtooth waveform was added to the signal being measured before the A/D conversion, and averaging the digital readings over one cycle of the sawtooth. It was intended to reduce bit error nonlinearities present in the A/D converter which could be expected to be as much as 16 gamma if not reduced. No such nonlinearities were detected in the output of the instrument which included the feature designed to reduce these nonlinearities. However, a small scale nonlinearity of plus or minus 2 gamma with a 64 gamma repetition rate was observed in the unit tested. A design improvement intended to eliminate this small scale nonlinearity was examined

    Springs of Florida

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    bulletin which documented the major and important springs in the state (Ferguson et al., 1947). This publication was revised in 1977, with many previously undocumented springs and many new water-quality analyses being added (Rosenau et al., 1977). The Florida Geological Survey's report on first magnitude springs (Scott et al., 2002) was the initial step in once again updating and revising the Springs of Florida bulletin. The new bulletin includes the spring descriptions and water-quality analyses from Scott et al. (2002). Nearly 300 springs were described in 1977. As of 2004, more than 700 springs have been recognized in the state and more are reported each year. To date, 33 first magnitude springs (with a flow greater than 100 cubic feet per second or approximately 64.6 million gallons of water per day) have been recognized in Florida, more than any other state or country (Rosenau et al., 1977). Our springs are a unique and invaluable natural resource. A comprehensive understanding of the spring systems will provide the basis for their protection and wise use. (Document pdf contains 677 pages

    The Contractual Foundation of Family-Business Law

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    Most U.S. businesses are family owned, and yet the law governing business organizations does not account adequately for family relationships. Nor have legal scholars paid sufficient attention to family businesses. Instead, legal scholars operate within a contractarian model of business organization law, which holds that a firm is comprised of a nexus of contracts among economically rational actors. Intimate relationships appear irrelevant except insofar as they affect contractual choices. Indeed, strictly speaking, there is no such thing as family-business law.This Article lays the foundation for a law of family business by expanding the contractarian model: a firm includes not just business contracts, but all bargains among participants that affect the business enterprise. The payoff for including family considerations is twofold. First, when family obligations introduce uncertainty, such as when co-owners of a business divorce, contract offers an explanatory resource for resolving disputes consistent with the parties’ expectations. Second, a contractual conception of the firm can guide the establishment of appropriate default rules for the interpretation and enforcement of family-business bargains

    Synthesis and Chemistry of Naphthalene Annulated Trienyl Iron Complexes: Potential Anticancer DNA Alkylation Reagents

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    Iron complex chemistry that opens a new door to the medicinal and pharmaceutical worlds is the aim of this research. Specifically, ortho-quinone methide moieties are intermediates in several antitumor drugs and have been identified as bioreductive alkylators of DNA. In our research, a class of iron compounds has been targeted to resemble these quinone methides. It is hoped that these new compounds could be modified to provide a window of opportunity toward the discovery of a selective mode of drug delivery. We have focused our efforts on generating a reactive transition metal complexed 5-membered ring analog of o-quinone methide based on our earlier reports of CpFe(CO)2 (butadienyl) complexes. In this vein, we have elaborated this chemistry by preparing and reacting a lithionaphthalene allene with CpFe(CO)2I. which gave the desired naphthalene annulated sigma complex. This complex thermally rearranged to the desired naphthalene annulated 5-membered ring quinone methide analog. Upon photolysis, this complex successfully mimicked its antecedent and alkylated alcohols. Thus, we here report our initial study of the preparation and chemistry of a transition metal complexed 5-membered ring quinone methide analog. Its reactions with alcohols have accomplished the first step toward the ultimate goal of selectively alkylating DNA
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