2,492 research outputs found

    The Natural History of Cave-Associated Populations of Eurycea l. longicauda with Notes on Sympatric Amphibian Species

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    The purpose of this study was to collect data on the natural history of the Long-tailed Salamander (Eurycea l. longicauda) in eastern Kentucky and West Virginia. The objectives of this research included characterization of epigean and hypogean habitat for this species, recording distances moved by individuals in populations associated with caves, and collection of data on courtship, oviposition, and larval development. The primary study site was Carter Caves State Park in Olive Hill, Kentucky. This area was visited from October 2007 to December 2008. Salamanders were photographed for identification based on unique pattern aberrancies and distances were measured between the encounter points when individuals were recaptured. Some individuals were observed to move considerable distances in relatively short periods of time while others appeared to remain in small areas for much of the year, but the cause of these different movement patterns is unknown. Eggs were not located, but larvae in a state of delayed development were located in a Greenbrier County, West Virginia cave. Data on sympatric amphibian species in caves are also discussed

    LCOGT Network Observatory Operations

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    We describe the operational capabilities of the Las Cumbres Observatory Global Telescope Network. We summarize our hardware and software for maintaining and monitoring network health. We focus on methodologies to utilize the automated system to monitor availability of sites, instruments and telescopes, to monitor performance, permit automatic recovery, and provide automatic error reporting. The same jTCS control system is used on telescopes of apertures 0.4m, 0.8m, 1m and 2m, and for multiple instruments on each. We describe our network operational model, including workloads, and illustrate our current tools, and operational performance indicators, including telemetry and metrics reporting from on-site reductions. The system was conceived and designed to establish effective, reliable autonomous operations, with automatic monitoring and recovery - minimizing human intervention while maintaining quality. We illustrate how far we have been able to achieve that.Comment: 13 pages, 9 figure

    Training volume and injury incidence in a professional rugby union team

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    Objective. To describe the incidence of injuries in a professional rugby team, and to identify any associations between injury rates and training volume. Methods. This retrospective, descriptive study included all injuries diagnosed as grade 1 and above in a South African Super 12 rugby team. Injury incidence and injury rates were calculated and compared with training volume and hours of match play. Results. Thirty-eight male rugby players were injured during the study period. The total number of annual injuries decreased from 50 (2002) to 38 (2004) (χ2=0.84, p=0.36). The number of new injuries showed a similar trend (χ2=2.81, p=0.09), while the number of recurring injuries increased over the 3-year period. There was a tendency for total in-season injury rates to decrease over the 3 years (χ2=2.89, p=0.09). The pre-season injury rate increased significantly over the 3 years (χ2=12.7, p<0.01), coupled with a reduction in training exposure over the pre-season phase. Conclusions. One has to be cognisant of the balance between performance improvement and injury risk when designing training programmes for elite rugby players. Although the reduction in training volume was associated with a slight reduction in the number of acute injuries and in-season injury rates over the three seasons, the performance of the team changed from 3rd to 7th (2002 and 2004, respectively). Further studies are required to determine the optimal training necessary to improve rugby performance while reducing injury rates

    Redshifts and Velocity Dispersions of Galaxy Clusters in the Horologium-Reticulum Supercluster

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    We present 118 new optical redshifts for galaxies in 12 clusters in the Horologium-Reticulum supercluster (HRS) of galaxies. For 76 galaxies, the data were obtained with the Dual Beam Spectrograph on the 2.3m telescope of the Australian National University at Siding Spring Observatory. After combining 42 previously unpublished redshifts with our new sample, we determine mean redshifts and velocity dispersions for 13 clusters, in which previous observational data were sparse. In six of the 13 clusters, the newly determined mean redshifts differ by more than 750 km/s from the published values. In the case of three clusters, A3047, A3109, and A3120, the redshift data indicate the presence of multiple components along the line of sight. The new cluster redshifts, when combined with other reliable mean redshifts for clusters in the HRS, are found to be distinctly bi-modal. Furthermore, the two redshift components are consistent with the bi-modal redshift distribution found for the inter-cluster galaxies in the HRS by Fleenor et al. (2005).Comment: 13 pages, 3 figures, Accepted to A

    Early Australian Optical and Radio Observations of Centaurus A

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    The discoveries of the radio source Centaurus A and its optical counterpart NGC 5128 were important landmarks in the history of Australian astronomy. NGC 5128 was first observed in August 1826 by James Dunlop during a survey of southern objects at the Parramatta Observatory, west of the settlement at Sydney Cove. The observatory had been founded a few years earlier by Thomas Brisbane, the new governor of the British colony of New South Wales. Just over 120 years later, John Bolton, Gordon Stanley and Bruce Slee discovered the radio source Centaurus A at the Dover Heights field station in Sydney, operated by CSIRO's Radiophysics Laboratory (the forerunner of the Australia Telescope National Facility). This paper will describe this early historical work and summarise further studies of Centaurus A by other Radiophysics groups up to 1960.Comment: 45 pages, 43 figure

    1989: Abilene Christian College Bible Lectures - Full Text

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    CHRIST AND CULTURE: The Problem of Secularism Being the Abilene Christian University Annual Bible Lectures 1989 Published by ACU PRESS 1634 Campus Court Abilene, Texas 7960

    Approaches for Studying Fish Production: Do River and Lake Researchers Have Different Perspectives? – Extended Abstract

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    Biased perspectives of fisheries researchers may hinder scientific progress and effective management if limiting factors controlling productivity go unrecognized. We investigated whether river and lake researchers used different approaches when studying salmonid production and whether any differences were ecologically supported. We assessed 564 peer‐reviewed papers published between 1966 and 2012 that studied salmonid production or surrogate variables (e.g., abundance, growth, biomass, population) and classified them into five major predictor variable categories: physical habitat, fertility (i.e., nutrients, bottom‐up), biotic, temperature, and pollution. The review demonstrated that river researchers primarily analyzed physical habitat (65% of studies) and lake researchers primarily analyzed fertility (45%) and biotic (51%) variables. Nevertheless, understudied variables were often statistically significant predictors of production for lake and river systems and, combined with other evidence, suggests that unjustified a priori assumptions may dictate the choice of independent variables studied. Broader consideration of potential limiting factors on fish production, greater research effort on understudied genera, and increased publication in broadly scoped journals would likely promote integration between lentic and lotic perspectives and improve fisheries management

    Large-Scale Velocity Structures in the Horologium-Reticulum Supercluster

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    We present 547 optical redshifts obtained for galaxies in the region of the Horologium-Reticulum Supercluster (HRS) using the 6dF multi-fiber spectrograph on the UK Schmidt Telescope at the Anglo Australian Observatory. The HRS covers an area of more than 12deg x 12deg on the sky centered at approximately RA = 03h19m, DEC = -50deg 02amin. Our 6dF observations concentrate upon the inter-cluster regions of the HRS, from which we describe four primary results. First, the HRS spans at least the redshift range from 17,000 to 22,500 km s^-1. Second, the overdensity of galaxies in the inter-cluster regions of the HRS in this redshift range is estimated to be 2.4, or del rho/ rho ~ 1.4. Third, we find a systematic trend of increasing redshift along a Southeast-Northwest (SE-NW) spatial axis in the HRS, in that the mean redshift of HRS members increases by more than 1500 km s^-1 from SE to NW over a 12 deg region. Fourth, the HRS is bi-modal in redshift with a separation of ~ 2500 km s^-1 (35 Mpc) between the higher and lower redshift peaks. This fact is particularly evident if the above spatial-redshift trend is fitted and removed. In short, the HRS appears to consist of two components in redshift space, each one exhibiting a similar systematic spatial-redshift trend along a SE-NW axis. Lastly, we compare these results from the HRS with the Shapley supercluster and find similar properties and large-scale features.Comment: 20 pages, 9 figures, accepted to A

    Mechanisms of carbon dioxide detection in the earthworm Dendrobaena veneta

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    IntroductionCarbon dioxide (CO2) is a critical biological signal that is noxious to many animals at high concentrations. The earthworm Dendrobaena veneta lives in subterranean burrows containing high levels of CO2 and respires through its skin. Despite the ecological and agricultural importance of earthworms, relatively little is known about how they make decisions in their environment, including their response to elevated levels of CO2.MethodsTo examine CO2 detection in this species, we designed the exudate assay, in which we placed an earthworm in a sealed container, exposed it to varying concentrations of CO2 for one minute, and recorded the amount of exudate secreted. Because earthworms excrete exudate in response to noxious stimuli, we hypothesized that the amount of exudate produced was proportional to the amount of irritation. We repeated these experiments after treatment with several blockers for molecules with potential involvement in CO2 detection, including carbonic anhydrases, guanylate cyclase, TRPA1, ASICs, and OTOP channels. We also confirmed the presence of homologous transcripts for each of these gene families in an epithelial transcriptome for D. veneta. Additionally, since organisms often detect CO2 levels indirectly by monitoring the conversion to carbonic acid (a weak acid), we used the exudate assay to evaluate aversion to additional weak acids (formic acid, acetic acid, and propionic acid).ResultsEarthworms excreted significantly more exudate in response to CO2 in a dosage-dependent manner, and this response was muted by the general carbonic anhydrase inhibitor acetazolamide, the carbonic anhydrase IX/XII inhibitor indisulam, the calcium channel blocker ruthenium red, the sodium channel blocker amiloride, and the acid-sensing ion channel blocker diminazene aceturate.DiscussionThese data provide evidence of the role of carbonic anhydrase and epithelial sodium channels in earthworm CO2 detection, establish that, similar to other subterranean-dwelling animals, earthworms are extremely tolerant of CO2, and contribute to our understanding of the mechanisms used by earthworms to detect and react to weak acids in their environment
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