160 research outputs found

    "Valuing Beach Closures on the Padre Island National Seashore"

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    In this paper we estimate the economic loss of hypothetical beach closures on the Padre Island National Seashore on the Gulf Coast of Texas. We use a travel cost random utility maximization (RUM) model with data from a random phone survey of Texas residents completed in 2001. We simulate realistic closures that may occur in event of an oil spill or other disruption. For comparison we valued the loss of beach closures in the heavily populated Galveston area. The aggregate losses on Padre Island were highest on weekend days in July estimated at 171,000perdayofclosure(2001171,000 per day of closure(2001). They were lowest on weekdays in September at 25,000.Pertriplosseswereabout25,000. Per trip losses were about 28. A similar closure of beaches near Galveston resulted in losses of 263,000(weekday)and263,000 (week day) and 852,000 (weekend day) with a per trip loss of $30.random utility model, beach use, non-market valuation

    Robust Likelihood-Based Survival Modeling with Microarray Data

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    Gene expression data can be associated with various clinical outcomes. In particular, these data can be of importance in discovering survival-associated genes for medical applications. As alternatives to traditional statistical methods, sophisticated methods and software programs have been developed to overcome the high-dimensional difficulty of microarray data. Nevertheless, new algorithms and software programs are needed to include practical functions such as the discovery of multiple sets of survival-associated genes and the incorporation of risk factors, and to use in the R environment which many statisticians are familiar with. For survival modeling with microarray data, we have developed a software program (called rbsurv) which can be used conveniently and interactively in the R environment. This program selects survival-associated genes based on the partial likelihood of the Cox model and separates training and validation sets of samples for robustness. It can discover multiple sets of genes by iterative forward selection rather than one large set of genes. It can also allow adjustment for risk factors in microarray survival modeling. This software package, the rbsurv package, can be used to discover survival-associated genes with microarray data conveniently.

    Robust Likelihood-Based Survival Modeling with Microarray Data

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    Gene expression data can be associated with various clinical outcomes. In particular, these data can be of importance in discovering survival-associated genes for medical applications. As alternatives to traditional statistical methods, sophisticated methods and software programs have been developed to overcome the high-dimensional difficulty of microarray data. Nevertheless, new algorithms and software programs are needed to include practical functions such as the discovery of multiple sets of survival-associated genes and the incorporation of risk factors, and to use in the R environment which many statisticians are familiar with. For survival modeling with microarray data, we have developed a software program (called rbsurv) which can be used conveniently and interactively in the R environment. This program selects survival-associated genes based on the partial likelihood of the Cox model and separates training and validation sets of samples for robustness. It can discover multiple sets of genes by iterative forward selection rather than one large set of genes. It can also allow adjustment for risk factors in microarray survival modeling. This software package, the rbsurv package, can be used to discover survival-associated genes with microarray data conveniently

    Workplace reform with changing management through the user participation workshop : the case study of Seiyo City Office / Ikumi Egawa

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    The research explains about workplace reform, aimed at improving productivity of General Affairs and Policy Planning department of Seiyo officeby changing management through the user participation workshop at 4th floor of Seiyo city office and on the changes of workplace reform. The purpose of this research is to find the changes that are worker's behaviour and worker’s awareness of workplace through workplace reform. The researchers surveyed changes, worker's behaviour and worker's awareness of workplace using workplace reform at 4th floor of Seiyo office as case study. In workplace reform, in order to create a place where new work style can be practiced, the researchers conducted the user participation workshops with workers a total of 6 times. Through the workshops, concept of work style and plan of renovation were proposed. In addition, the researchers did a survey using two methods which were a set of questionnaire and 3 observationsthat is before the workplace renovation, 3 months after the renovation, and 1 year and 3 months after the renovation. The findings obtained from the questionnaire in the first three months after the renovation showed that the opinions of the workers were divided between pros and cons against workplace reform. However, the survey of 1 year and three months after the renovation showed that almost all workers are satisfied with the new environment. In addition, the researchers found that a positive correlation exist between participation rate of workshops and the satisfaction level. The findings suggest the worth of workshops for workplace reform. In the Observation Survey, the workers needed to select a place freely where they can work comfortably after the workplace reform. For example, they chose to work in refresh space. In addition, the findings from the survey showed that the floor became livelier when the participation rate increses at that workplace. Additionally, the participants became more conscious of the work style such as features of work style, after workplace renovation; they are able to clearly differentiate between short intermittent works separated by conversation and phone and personal work on concentration

    LOFAR discovery of a double radio halo system in Abell 1758 and radio/X-ray study of the cluster pair

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    Radio halos and radio relics are diffuse synchrotron sources that extend over Mpc-scales and are found in a number of merger galaxy clusters. They are believed to form as a consequence of the energy that is dissipated by turbulence and shocks in the intra-cluster medium (ICM). However, the precise physical processes that generate these steep synchrotron spectrum sources are still poorly constrained. We present a new LOFAR observation of the double galaxy cluster Abell 1758. This system is composed of A1758N, a massive cluster hosting a known giant radio halo, and A1758S, which is a less massive cluster whose diffuse radio emission is confirmed here for the first time. Our observations have revealed a radio halo and a candidate radio relic in A1758S, and a suggestion of emission along the bridge connecting the two systems which deserves confirmation. We combined the LOFAR data with archival VLA and GMRT observations to constrain the spectral properties of the diffuse emission. We also analyzed a deep archival Chandra observation and used this to provide evidence that A1758N and A1758S are in a pre-merger phase. The ICM temperature across the bridge that connects the two systems shows a jump which might indicate the presence of a transversal shock generated in the initial stage of the merger

    The opto-mechanical design of the GMT-Consortium Large Earth Finder (G-CLEF)

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    The GMT-Consortium Large Earth Finder (G-CLEF) will be part of the first generation instrumentation suite for the Giant Magellan Telescope (GMT). G-CLEF is a general purpose echelle spectrograph operating in the optical passband with precision radial velocity (PRV) capability. The measurement precision goal of G-CLEF is 10 cm/sec; necessary for the detection of Earth analogues. This goal imposes challenging stability requirements on the optical mounts and spectrograph support structures especially when considering the instrument's operational environment. G-CLEF's accuracy will be influenced by changes in temperature and ambient air pressure, vibration, and micro gravity-vector variations caused by normal telescope motions. For these reasons we have chosen to enclose G-CLEF's spectrograph in a wellinsulated, vibration-isolated vacuum chamber in a gravity invariant location on GMT's azimuth platform. Additional design constraints posed by the GMT telescope include; a limited space envelope, a thermal leakage ceiling, and a maximum weight allowance. Other factors, such as manufacturability, serviceability, available technology, and budget are also significant design drivers. G-CLEF will complete its Critical Design phase in mid-2018. In this paper, we discuss the design of GCLEF's optical mounts and support structures including the choice of a low-CTE carbon-fiber optical bench. We discuss the vacuum chamber and vacuum systems. We discuss the design of G-CLEF's insulated enclosure and thermal control systems which simultaneously maintain the spectrograph at milli-Kelvin level stability and limit thermal leakage into the telescope dome. Also discussed are micro gravity-vector variations caused by normal telescope slewing, their uncorrected influence on image motion, and how they are dealt with in the design. We discuss G-CLEF's front-end assembly and fiber-feed system as well as other interface, integration and servicing challenges presented by the telescope, enclosure, and neighboring instrumentation. This work has been supported by the GMTO Corporation, a non-profit organization operated on behalf of an international consortium of universities and institutions: Arizona State University, Astronomy Australia Ltd, the Australian National University, the Carnegie Institution for Science, Harvard University, the Korea Astronomy and Space Science Institute, the SĂŁo Paulo Research Foundation, the Smithsonian Institution, the University of Texas at Austin, Texas AM University, the University of Arizona, and the University of Chicago

    Halo ellipticity of GAMA galaxy groups from KiDS weak lensing

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    We constrain the average halo ellipticity of ~2 600 galaxy groups from the Galaxy And Mass Assembly (GAMA) survey, using the weak gravitational lensing signal measured from the overlapping Kilo Degree Survey (KiDS). To do so, we quantify the azimuthal dependence of the stacked lensing signal around seven different proxies for the orientation of the dark matter distribution, as it is a priori unknown which one traces the orientation best. On small scales, the major axis of the brightest group/cluster member (BCG) provides the best proxy, leading to a clear detection of an anisotropic signal. In order to relate that to a halo ellipticity, we have to adopt a model density profile. We derive new expressions for the quadrupole moments of the shear field given an elliptical model surface mass density profile. Modeling the signal with an elliptical Navarro-Frenk-White (NFW) profile on scales < 250 kpc, which roughly corresponds to half the virial radius, and assuming that the BCG is perfectly aligned with the dark matter, we find an average halo ellipticity of e_h=0.38 +/- 0.12. This agrees well with results from cold-dark-matter-only simulations, which typically report values of e_h ~ 0.3. On larger scales, the lensing signal around the BCGs does not trace the dark matter distribution well, and the distribution of group satellites provides a better proxy for the halo's orientation instead, leading to a 3--4 sigma detection of a non-zero halo ellipticity at scales between 250 kpc and 750 kpc. Our results suggest that the distribution of stars enclosed within a certain radius forms a good proxy for the orientation of the dark matter within that radius, which has also been observed in hydrodynamical simulations

    Genetic Variants For Head Size Share Genes and Pathways With Cancer

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    The size of the human head is highly heritable, but genetic drivers of its variation within the general population remain unmapped. We perform a genome-wide association study on head size (N = 80,890) and identify 67 genetic loci, of which 50 are novel. Neuroimaging studies show that 17 variants affect specific brain areas, but most have widespread effects. Gene set enrichment is observed for various cancers and the p53, Wnt, and ErbB signaling pathways. Genes harboring lead variants are enriched for macrocephaly syndrome genes (37-fold) and high-fidelity cancer genes (9-fold), which is not seen for human height variants. Head size variants are also near genes preferentially expressed in intermediate progenitor cells, neural cells linked to evolutionary brain expansion. Our results indicate that genes regulating early brain and cranial growth incline to neoplasia later in life, irrespective of height. This warrants investigation of clinical implications of the link between head size and cancer
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