2,186 research outputs found

    Comparison of Movement Patterns in Captive-Released Eastern Hellbenders (Cryptobranchus alleganiensis alleganiensis) Using Three Different Release Methods

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    Eastern hellbender (Cryptobranchus alleganiensis alleganiensis) population size has declined throughout much of its range. Previous captive-release headstarting programs have resulted in minimal success, presumably due to movement of captive-released animals away from the release site. This study aimed to increase the success of hellbender headstarting programs by assessing the effectiveness of three release methods. Releases were conducted in two stream sites within the Allegheny River drainage. Streams were similar; however stream A contained a higher boulder density. In each site, three salamanders were placed individually in cages, three salamanders were placed individually in nest boxes with the entrance blocked with screen, and three salamanders were released directly under cover rocks. Animals were monitored between 18 June 2013 and 12 October 2013 using radio telemetry. Results showed little difference in total movement and survivorship between stream sites or treatments. Number of movements was marginally significantly higher in stream B. The number of movements was not different between release types. Overall survival was low; only three animals were found alive for longer than six months. Four animals were never recovered, three were found dead, and eight transmitters were found. Movement was most dependent on the phase of the moon. Both distance and frequency of movement increased with greater moon phase. Captive-released animals generally moved further than what has been reported in wild hellbenders, with an average cumulative distance moved of 653±138 m (SE). The information gathered from this study could aid further captive-rearing projects, as well as inform monitoring and survey efforts

    Hexen-Polka

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    https://digitalcommons.library.umaine.edu/mmb-ps/3598/thumbnail.jp

    Thermal Diagnostics with the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory: A Validated Method for Differential Emission Measure Inversions

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    We present a new method for performing differential emission measure (DEM) inversions on narrow-band EUV images from the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). The method yields positive definite DEM solutions by solving a linear program. This method has been validated against a diverse set of thermal models of varying complexity and realism. These include (1) idealized gaussian DEM distributions, (2) 3D models of NOAA Active Region 11158 comprising quasi-steady loop atmospheres in a non-linear force-free field, and (3) thermodynamic models from a fully-compressible, 3D MHD simulation of AR corona formation following magnetic flux emergence. We then present results from the application of the method to AIA observations of Active Region 11158, comparing the region's thermal structure on two successive solar rotations. Additionally, we show how the DEM inversion method can be adapted to simultaneously invert AIA and XRT data, and how supplementing AIA data with the latter improves the inversion result. The speed of the method allows for routine production of DEM maps, thus facilitating science studies that require tracking of the thermal structure of the solar corona in time and space.Comment: 21 pages, 18 figures, accepted for publication in Ap

    Self-adjoint symmetry operators connected with the magnetic Heisenberg ring

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    We consider symmetry operators a from the group ring C[S_N] which act on the Hilbert space H of the 1D spin-1/2 Heisenberg magnetic ring with N sites. We investigate such symmetry operators a which are self-adjoint (in a sence defined in the paper) and which yield consequently observables of the Heisenberg model. We prove the following results: (i) One can construct a self-adjoint idempotent symmetry operator from every irreducible character of every subgroup of S_N. This leads to a big manifold of observables. In particular every commutation symmetry yields such an idempotent. (ii) The set of all generating idempotents of a minimal right ideal R of C[S_N] contains one and only one idempotent which ist self-adjoint. (iii) Every self-adjoint idempotent e can be decomposed into primitive idempotents e = f_1 + ... + f_k which are also self-adjoint and pairwise orthogonal. We give a computer algorithm for the calculation of such decompositions. Furthermore we present 3 additional algorithms which are helpful for the calculation of self-adjoint operators by means of discrete Fourier transforms of S_N. In our investigations we use computer calculations by means of our Mathematica packages PERMS and HRing.Comment: 13 page

    Discrimination between pure states and mixed states

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    In this paper, we discuss the problem of determining whether a quantum system is in a pure state, or in a mixed state. We apply two strategies to settle this problem: the unambiguous discrimination and the maximum confidence discrimination. We also proved that the optimal versions of both strategies are equivalent. The efficiency of the discrimination is also analyzed. This scheme also provides a method to estimate purity of quantum states, and Schmidt numbers of composed systems

    Constructing a Learning Community: One Medical Schools Needs Assessment

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    https://digitalcommons.unmc.edu/emet_posters/1006/thumbnail.jp

    Dose Modeling Evaluations and Technical Support Document For the Authorized Limits Request for the DOE-Owned Property Outside the Limited Area, Paducah Gaseous Diffusion Plant Paducah, Kentucky

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    Environmental assessments and remediation activities are being conducted by the U.S. Department of Energy (DOE) at the Paducah Gaseous Diffusion Plant (PGDP), Paducah, Kentucky. The Oak Ridge Institute for Science and Education (ORISE), a DOE prime contractor, was contracted by the DOE Portsmouth/Paducah Project Office (DOE-PPPO) to conduct radiation dose modeling analyses and derive single radionuclide soil guidelines (soil guidelines) in support of the derivation of Authorized Limits (ALs) for 'DOE-Owned Property Outside the Limited Area' ('Property') at the PGDP. The ORISE evaluation specifically included the area identified by DOE restricted area postings (public use access restrictions) and areas licensed by DOE to the West Kentucky Wildlife Management Area (WKWMA). The licensed areas are available without restriction to the general public for a variety of (primarily) recreational uses. Relevant receptors impacting current and reasonably anticipated future use activities were evaluated. In support of soil guideline derivation, a Conceptual Site Model (CSM) was developed. The CSM listed radiation and contamination sources, release mechanisms, transport media, representative exposure pathways from residual radioactivity, and a total of three receptors (under present and future use scenarios). Plausible receptors included a Resident Farmer, Recreational User, and Wildlife Worker. single radionuclide soil guidelines (outputs specified by the software modeling code) were generated for three receptors and thirteen targeted radionuclides. These soil guidelines were based on satisfying the project dose constraints. For comparison, soil guidelines applicable to the basic radiation public dose limit of 100 mrem/yr were generated. Single radionuclide soil guidelines from the most limiting (restrictive) receptor based on a target dose constraint of 25 mrem/yr were then rounded and identified as the derived soil guidelines. An additional evaluation using the derived soil guidelines as inputs into the code was also performed to determine the maximum (peak) dose for all receptors. This report contains the technical basis in support of the DOE?s derivation of ALs for the 'Property.' A complete description of the methodology, including an assessment of the input parameters, model inputs, and results is provided in this report. This report also provides initial recommendations on applying the derived soil guidelines
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