2,606 research outputs found

    Determination of the Spawning Season of Bigmouth Sleeper in Puerto Rico by Examination of Gonad Maturation and Reproductive Hormone Cycles

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    Bigmouth sleepers, Gobiomorus dormitor, are diadromous fish that have potential for hatchery production as both food and sport fish and for conservation purposes. Understanding of bigmouth sleeper maturation and seasonal hormone cycling are necessary in order to realize hatchery production. Therefore, seasonal trends in gonadosomatic index (GSI) and plasma vitellogenin, estradiol, progesterone and total testosterone concentrations were examined in wild and captive populations in Puerto Rico during the presumed spawning season. The spawning season for wild river populations of bigmouth sleepers was protracted over several months, but peaks in male testosterone (6.5 ng/mL) and female vitellogenin (11.3 ng/mL), estradiol (3.3 ng/mL), and GSI (9.5—12.0%) demonstrated that the bigmouth sleeper spawning season occurred primarily in July and August in southwestern Puerto Rico. Captive female broodstock held in shallow hatchery ponds demonstrated accelerated maturation, presumably due to warmer water temperatures in the ponds. Therefore, induced and natural spawning attempts using captive female bigmouth sleeper broodstock should be conducted from June through July. However, advanced gonadal maturation and increased testosterone production in captive males was minimal. Hence, induced spawning for captive rearing purposes should use wild broodstock captured during the peak of the natural spawning season in July and August

    Calderbank-Steane-Shor Holographic Quantum Error Correcting Codes

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    We expand the class of holographic quantum error correcting codes by developing the notion of block perfect tensors, a wider class that includes previously defined perfect tensors. The relaxation of this constraint opens up a range of other holographic codes. We demonstrate this by introducing the self-dual CSS heptagon holographic code, based on the 7-qubit Steane code. Finally we show promising thresholds for the erasure channel by applying a straightforward, optimal erasure decoder to the heptagon code and benchmark it against existing holographic codes.Comment: 5 pages, 3 figure

    The Effectiveness of fMRI Data when Combined with Polygraph Data

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    The Integrated Zone Comparison Technique (IZCT) was utilized with computerized polygraph instrumentation and the Academy for Scientific Investigative Training’s Horizontal Scoring System ASIT PolySuite algorithm, as part of a blind study in the detection of deception. This paper represents a synergy analysis of combining fMRI only deception data with each of the three individual physiological parameters that are used in polygraph. They include the electro-dermal response (EDR), pneumo, and cardio measurements. In addition, we compared the detection accuracy analysis using each single parameter by itself. Th e fMRI score and each individual polygraph parameter score on individual subjects were averaged to establish an overall score

    Thermodynamics as an alternative foundation for zero-temperature density functional theory and spin density functional theory

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    Thermodynamics provides a transparent definition of the free energy of density functional theory (DFT), and of its derivatives - the potentials, at finite temperatures T. By taking the T to 0 limit, it is shown here that both DFT and spin-dependent DFT (for ground states) suffer from precisely the same benign ambiguities: (a) charge and spin quantization lead to "up to a constant" indeterminacies in the potential and the magnetic field respectively, and (b) the potential in empty subspaces is undetermined but irrelevant. Surprisingly, these simple facts were inaccessible within the standard formulation, leading to recent discussions of apparent difficulties within spin-DFT.Comment: RevTeX, to appear in Phys. Rev.

    Rap1 and Canoe/afadin are essential for establishment of apical-basal polarity in the Drosophila embryo

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    The small GTPase Rap1 and the actin-junctional linker protein Canoe/afadin are essential for the initial establishment of polarity in Drosophila, acting upstream of Bazooka/Par3 and the adherens junctions. However, feedback and cross-regulation occur, so polarity establishment is regulated by a network of proteins rather than a linear pathway.The establishment and maintenance of apical–basal cell polarity is critical for assembling epithelia and maintaining organ architecture. Drosophila embryos provide a superb model. In the current view, apically positioned Bazooka/Par3 is the initial polarity cue as cells form during cellularization. Bazooka then helps to position both adherens junctions and atypical protein kinase C (aPKC). Although a polarized cytoskeleton is critical for Bazooka positioning, proteins mediating this remained unknown. We found that the small GTPase Rap1 and the actin-junctional linker Canoe/afadin are essential for polarity establishment, as both adherens junctions and Bazooka are mispositioned in their absence. Rap1 and Canoe do not simply organize the cytoskeleton, as actin and microtubules become properly polarized in their absence. Canoe can recruit Bazooka when ectopically expressed, but they do not obligatorily colocalize. Rap1 and Canoe play continuing roles in Bazooka localization during gastrulation, but other polarity cues partially restore apical Bazooka in the absence of Rap1 or Canoe. We next tested the current linear model for polarity establishment. Both Bazooka and aPKC regulate Canoe localization despite being “downstream” of Canoe. Further, Rap1, Bazooka, and aPKC, but not Canoe, regulate columnar cell shape. These data reshape our view, suggesting that polarity establishment is regulated by a protein network rather than a linear pathway

    Herschel observations of EXtraordinary Sources: Analysis of the full Herschel/HIFI molecular line survey of Sagittarius B2(N)

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    A sensitive broadband molecular line survey of the Sagittarius B2(N) star-forming region has been obtained with the HIFI instrument on the Herschel Space Observatory, offering the first high-spectral resolution look at this well-studied source in a wavelength region largely inaccessible from the ground (625-157 um). From the roughly 8,000 spectral features in the survey, a total of 72 isotopologues arising from 44 different molecules have been identified, ranging from light hydrides to complex organics, and arising from a variety of environments from cold and diffuse to hot and dense gas. We present an LTE model to the spectral signatures of each molecule, constraining the source sizes for hot core species with complementary SMA interferometric observations, and assuming that molecules with related functional group composition are cospatial. For each molecule, a single model is given to fit all of the emission and absorption features of that species across the entire 480-1910 GHz spectral range, accounting for multiple temperature and velocity components when needed to describe the spectrum. As with other HIFI surveys toward massive star forming regions, methanol is found to contribute more integrated line intensity to the spectrum than any other species. We discuss the molecular abundances derived for the hot core, where the local thermodynamic equilibrium approximation is generally found to describe the spectrum well, in comparison to abundances derived for the same molecules in the Orion KL region from a similar HIFI survey.Comment: Accepted to ApJ. 64 pages, 14 figures. Truncated abstrac
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