959 research outputs found

    A Study of Selected Chemical and Biological Conditions of the Lower Trinity River and the Upper Trinity Bay

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    Concern over the effects of water development projects on coastal nurseries prompted the Department of Wildlife Science of Texas A&M University, with the cooperation of the UO So Bureau of Commercial Fisheries, Galveston, to undertake a study of a threatened nursery in the Galveston Bay System. A long-range program for the development of the Trinity River Drainage Basin includes the construction of several multi-purpose reservoirs along the main river (Fickessen, 1965). Of immediate threat to Galveston Bay nurseries was the reservoir to be constructed at Wallisville, Texas (Trinity River Mile 3.9)0 The site is close to Trinity Bay and the dam will traverse the relatively wide deltaic region of the Trinity River (Figure 2). The completed dam will serve as an effective barrier to salt water. Approximately 12,500 acres of marsh behind the dam will be come a freshwater conservation pool. The marsh area below the dam (8,200 acres) will also be modified through changes in the freshwater flow. It is assumed that tile Wallisville Dam will be completed and that many of the conditions described here for the study area will be drastically changed. The aim of this study was to gather data which would establish file role of the threatened marsh as a nursery for important marine and estuarine species It is recognized that these data will serve in planning and evaluating future water projects of this nature. Data reported here cover the period from March, 1966, through May, 1968. The study was limited to commercially important species with special emphasis given to the shrimps. The Bureau of Commercial Fisheries had maintained collecting stations in trinity Bay and made several preliminary investigations in the area of the proposed Wallisville Reservoir, but the actual extent to which commercially important species were utilizing these threatened wetlands was unknown. This paper attempts to demonstrate the extent to which the marsh has been utilized by the white shrimp (Penaeus setiferus Linnaeus), the brown shrimp (Penaeus aztecus Ives), the blue crab (Callinectes sapidus Rathburl), and the Gulf menhaden (Brevoortia patronus Goode). Some of the information presented here may be pertinent to an understanding of the same species in other low salinity environments

    The SQM/COSMO filter: reliable native pose identification based on the quantum-mechanical description of protein–ligand interactions and implicit COSMO solvation

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    Current virtual screening tools are fast, but reliable scoring is elusive. Here, we present the "SQM/COSMO filter", a novel scoring function featuring a quantitative semiempirical quantum mechanical (SQM) description of all types of noncovalent interactions coupled with implicit COSMO solvation. We show unequivocally that it outperforms eight widely used scoring functions. The accuracy and chemical generality of the SQM/COSMO filter make it a perfect tool for late stages of virtual screening

    Coordinating government and community support for community language teaching in Australia: Overview with special attention to New South Wales

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    An overview of formal government language-in-education planning for community languages (CLs) that has been undertaken in Australia and New South Wales is provided, moving from the more informal programmes provided in the 1980s to school-oriented programmes and training at the turn of the century. These programmes depend on community support; for many of the teachers from the communities, methodological training is needed to complement their language and cultural skills. At the same time, Commonwealth (Federal) and State support for CL programmes has improved their quality and provides students with opportunities to study CLs at the senior secondary matriculation level. The paper concludes with specific recommendations for greater recognition of CL schools and for greater attention to CL teacher preparation

    Minimizing the stochasticity of halos in large-scale structure surveys

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    In recent work (Seljak, Hamaus and Desjacques 2009) it was found that weighting central halo galaxies by halo mass can significantly suppress their stochasticity relative to the dark matter, well below the Poisson model expectation. In this paper we extend this study with the goal of finding the optimal mass-dependent halo weighting and use NN-body simulations to perform a general analysis of halo stochasticity and its dependence on halo mass. We investigate the stochasticity matrix, defined as Cij<(δibiδm)(δjbjδm)>C_{ij}\equiv<(\delta_i -b_i\delta_m)(\delta_j-b_j\delta_m)>, where δm\delta_m is the dark matter overdensity in Fourier space, δi\delta_i the halo overdensity of the ii-th halo mass bin and bib_i the halo bias. In contrast to the Poisson model predictions we detect nonvanishing correlations between different mass bins. We also find the diagonal terms to be sub-Poissonian for the highest-mass halos. The diagonalization of this matrix results in one large and one low eigenvalue, with the remaining eigenvalues close to the Poisson prediction 1/nˉ1/\bar{n}, where nˉ\bar{n} is the mean halo number density. The eigenmode with the lowest eigenvalue contains most of the information and the corresponding eigenvector provides an optimal weighting function to minimize the stochasticity between halos and dark matter. We find this optimal weighting function to match linear mass weighting at high masses, while at the low-mass end the weights approach a constant whose value depends on the low-mass cut in the halo mass function. Finally, we employ the halo model to derive the stochasticity matrix and the scale-dependent bias from an analytical perspective. It is remarkably successful in reproducing our numerical results and predicts that the stochasticity between halos and the dark matter can be reduced further when going to halo masses lower than we can resolve in current simulations.Comment: 17 pages, 14 figures, matched the published version in Phys. Rev. D including one new figur

    English as the International Language of Research

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    The annual world output of research papers and scholarly ar ticles is large and increasing, and there is little doubt that English is the medium of publication for the majority of such papers. However, closer analyses of the available data reveal rather few papers from non- native speakers, especially from the Third World. This imbalance sug gests that English is only the International Language of Research in a receptive sense. It needs to become so in a productive sense as well if Third World investment in doctoral scholarship etc. is to remain justified. Unfortunately, the ESP profession has concentrated on undergraduate teaching programmes and rather neglected the teaching of Research English. However, there are now welcome signs of change, which may therefore aid a process of making English a truly international language rather than one over-restricted in terms of publication sources to the Northern Hemisphere.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68423/2/10.1177_003368828501600101.pd

    Effects and Detectability of Quasi-Single Field Inflation in the Large-Scale Structure and Cosmic Microwave Background

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    Quasi-single field inflation predicts a peculiar momentum dependence in the squeezed limit of the primordial bispectrum which smoothly interpolates between the local and equilateral models. This dependence is directly related to the mass of the isocurvatons in the theory which is determined by the supersymmetry. Therefore, in the event of detection of a non-zero primordial bispectrum, additional constraints on the parameter controlling the momentum-dependence in the squeezed limit becomes an important question. We explore the effects of these non-Gaussian initial conditions on large-scale structure and the cosmic microwave background, with particular attention to the galaxy power spectrum at large scales and scale-dependence corrections to galaxy bias. We determine the simultaneous constraints on the two parameters describing the QSF bispectrum that we can expect from upcoming large-scale structure and cosmic microwave background observations. We find that for relatively large values of the non-Gaussian amplitude parameters, but still well within current uncertainties, galaxy power spectrum measurements will be able to distinguish the QSF scenario from the predictions of the local model. A CMB likelihood analysis, as well as Fisher matrix analysis, shows that there is also a range of parameter values for which Planck data may be able distinguish between QSF models and the related local and equilateral shapes. Given the different observational weightings of the CMB and LSS results, degeneracies can be significantly reduced in a joint analysis.Comment: 27 pages, 14 figure

    History of oceanic front development in the New Zealand sector of the Southern Ocean during the Cenozoic--a synthesis

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    The New Zealand sector of the Southern Ocean (NZSSO) has opened about the Indian-Pacific spreading ridge throughout the Cenozoic. Today the NZSSO is characterised by broad zonal belts of antarctic (cold), subantarctic (cool), and subtropical (warm) surface-water masses separated by prominent oceanic fronts: the Subtropical Front (STF) c. 43deg.S, Subantarctic Front (SAF) c. 50deg.S, and Antarctic Polar Front (AAPF) c. 60deg.S. Despite a meagre database, the broad pattern of Cenozoic evolution of these fronts is reviewed from the results of Deep Sea Drilling Project-based studies of sediment facies, microfossil assemblages and diversity, and stable isotope records, as well as from evidence in onland New Zealand Cenozoic sequences. Results are depicted schematically on seven paleogeographic maps covering the NZSSO at 10 m.y. intervals through the Cenozoic. During the Paleocene and most of the Eocene (65-35 Ma), the entire NZSSO was under the influence of warm to cool subtropical waters, with no detectable oceanic fronts. In the latest Eocene (c. 35 Ma), a proto-STF is shown separating subantarctic and subtropical waters offshore from Antarctica, near 65deg.S paleolatitude. During the earliest Oligocene, this front was displaced northwards by development of an AAPF following major global cooling and biotic turnover associated with ice sheet expansion to sea level on East Antarctica. Early Oligocene full opening (c. 31 Ma) of the Tasmanian gateway initiated vigorous proto-circum-Antarctic flow of cold/cool waters, possibly through a West Antarctic seaway linking the southern Pacific and Atlantic Oceans, including detached northwards "jetting" onto the New Zealand plateau where condensation and unconformity development was widespread in cool-water carbonate facies. Since this time, a broad tripartite division of antarctic, subantarctic, and subtropical waters has existed in the NZSSO, including possible development of a proto-SAF within the subantarctic belt. In the Early-early Middle Miocene (25-15 Ma), warm subtropical waters expanded southwards into the northern NZSSO, possibly associated with reduced ice volume on East Antarctica but particularly with restriction of the Indonesian gateway and redirection of intensified warm surface flows southwards into the Tasman Sea, as well as complete opening of the Drake gateway by 23 Ma allowing more complete decoupling of cool circum-Antarctic flow from the subtropical waters. During the late Middle-Late Miocene (15-5 Ma), both the STF and SAF proper were established in their present relative positions across and about the Campbell Plateau, respectively, accompanying renewed ice buildup on East Antarctica and formation of a permanent ice sheet on West Antarctica, as well as generally more expansive and intensified circum-Antarctic flow. The ultimate control on the history of oceanic front development in the NZSSO has been plate tectonics through its influence on the paleogeographic changes of the Australian-New Zealand-Antarctic continents and their intervening oceanic basins, the timing of opening and closing of critical seaways, the potential for submarine ridges and plateaus to exert some bathymetric control on the location of fronts, and the evolving ice budget on the Antarctic continent. The broad trends of the Cenozoic climate curve for New Zealand deduced from fossil evidence in the uplifted marine sedimentary record correspond well to the principal paleoceanographic events controlling the evolution and migration of the oceanic fronts in the NZSSO

    Clustering of quintessence on horizon scales and its imprint on HI intensity mapping

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    Quintessence can cluster only on horizon scales. What is the effect on the observed matter distribution? To answer this, we need a relativistic approach that goes beyond the standard Newtonian calculation and deals properly with large scales. Such an approach has recently been developed for the case when dark energy is vacuum energy, which does not cluster at all. We extend this relativistic analysis to deal with dynamical dark energy. Using three quintessence potentials as examples, we compute the angular power spectrum for the case of an HI intensity map survey. Compared to the concordance model with the same small-scale power at z = 0, quintessence boosts the angular power by up to 15% at high redshifts, while power in the two models converges at low redshifts. The difference is mainly due to the background evolution, driven mostly by the normalization of the power spectrum today. The dark energy perturbations make only a small contribution on the largest scales, and a negligible contribution on smaller scales. Ironically, the dark energy perturbations remove the false boost of large-scale power that arises if we impose the (unphysical) assumption that the dark energy is smooth.Web of Scienc

    The Role of Organizational Control Systems in Employees’ Organizational Trust and Performance Outcomes

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    This study examined how organizational control is related to employees’ organizational trust. We specifically focus on how different forms of control (process, outcome, and normative) relate to employees’ trust in their employing organizations and examine whether such trust in turn relates positively to employee job performance (task performance and organizational citizenship behavior). In addition, and in response to the recommendations of past research, we examined these relationships in a high control and compliance-based cultural context. Using data from 105 employee–supervisor dyads from professional services firms in Singapore, we find support for our hypothesized model. The implications of the results for theory and practice, and directions for future research, are discussed.Economics of Technology and Innovatio
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