2,234 research outputs found

    The Dark Side of Galaxy Color: evidence from new SDSS measurements of galaxy clustering and lensing

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    The age matching model has recently been shown to predict correctly the luminosity L and g-r color of galaxies residing within dark matter halos. The central tenet of the model is intuitive: older halos tend to host galaxies with older stellar populations. In this paper, we demonstrate that age matching also correctly predicts the g-r color trends exhibited in a wide variety of statistics of the galaxy distribution for stellar mass M* threshold samples. In particular, we present new measurements of the galaxy two-point correlation function and the galaxy-galaxy lensing signal as a function of M* and g-r color from the Sloan Digital Sky Survey, and show that age matching exhibits remarkable agreement with these and other statistics of low-redshift galaxies. In so doing, we also demonstrate good agreement between the galaxy-galaxy lensing observed by SDSS and the signal predicted by abundance matching, a new success of this model. We describe how age matching is a specific example of a larger class of Conditional Abundance Matching models (CAM), a theoretical framework we introduce here for the first time. CAM provides a general formalism to study correlations at fixed mass between any galaxy property and any halo property. The striking success of our simple implementation of CAM provides compelling evidence that this technique has the potential to describe the same set of data as alternative models, but with a dramatic reduction in the required number of parameters. CAM achieves this reduction by exploiting the capability of contemporary N-body simulations to determine dark matter halo properties other than mass alone, which distinguishes our model from conventional approaches to the galaxy-halo connection.Comment: references added, minor adjustments to text and notatio

    Economic Growth, Productivity, and Public Education Funding: Is South Carolina a Death Spiral State?

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    As a result of the Great Recession of 2007-2009, most states experienced declines in employment, consumer spending, and economic productivity

    Precursors To and Pathways Through Conversion: Catalytic Experiences of Born Again Christian College Students

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    Born again Christians are a significant religious population in the United States, and throughout the world. The process by which a born again identity is assumed is not clearly described in the research literature. Therefore, we asked 18 born again Christian college students a series of questions designed to uncover what led to their identity of being born again. Responses fell into three overarching themes. First, participants described exposure within relationships to God’s principles. Second, participants noted the influence of introspection and reflection on their lives apart from the influence of God. Third, participants had an active response in which they reported such things as recognizing conviction by the Holy Spirit, that they decided to act on that conviction, and that they took action to follow Jesus. Findings are discussed within the framework of Cohen and Hill’s (2007) theory of religion as culture

    Molecular phylogeny of Subtribe Artemisiinae (Asteraceae), including Artemisia and its allied and segregate genera

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    BACKGROUND: Subtribe Artemisiinae of Tribe Anthemideae (Asteraceae) is composed of 18 largely Asian genera that include the sagebrushes and mugworts. The subtribe includes the large cosmopolitan, wind-pollinated genus Artemisia, as well as several smaller genera and Seriphidium, that altogether comprise the Artemisia-group. Circumscription and taxonomic boundaries of Artemisia and the placements of these small segregate genera is currently unresolved. RESULTS: We constructed a molecular phylogeny for the subtribe using the internal transcribed spacers (ITS) of nuclear ribosomal DNA analyzed with parsimony, likelihood, and Bayesian criteria. The resulting tree is comprised of three major clades that correspond to the radiate genera (e.g., Arctanthemum and Dendranthema), and two clades of Artemisia species. All three clades have allied and segregate genera embedded within each. CONCLUSIONS: The data support a broad concept of Artemisia s.l. that includes Neopallasia, Crossostephium, Filifolium, Seriphidium, and Sphaeromeria. However, the phylogeny excludes Elachanthemum, Kaschgaria, and Stilnolepis from the Artemisia-group. Additionally, the monophyly of the four subgenera of Artemisia is also not supported, with the exception of subg. Dracunculus. Homogamous, discoid capitula appear to have arisen in parallel four to seven times, with the loss of ray florets. Thus capitular morphology is not a reliable taxonomic character, which traditionally has been one of the defining characters

    Molecular phylogeny of Subtribe Artemisiinae (Asteraceae), including \u3ci\u3eArtemisia\u3c/i\u3e and its allied and segregate genera

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    Background: Subtribe Artemisiinae of Tribe Anthemideae (Asteraceae) is composed of 18 largely Asian genera that include the sagebrushes and mugworts. The subtribe includes the large cosmopolitan, wind-pollinated genus Artemisia, as well as several smaller genera and Seriphidium, that altogether comprise the Artemisia-group. Circumscription and taxonomic boundaries of Artemisia and the placements of these small segregate genera is currently unresolved. Results: We constructed a molecular phylogeny for the subtribe using the internal transcribed spacers (ITS) of nuclear ribosomal DNA analyzed with parsimony, likelihood, and Bayesian criteria. The resulting tree is comprised of three major clades that correspond to the radiate genera (e.g., Arctanthemum and Dendranthema), and two clades of Artemisia species. All three clades have allied and segregate genera embedded within each. Conclusions: The data support a broad concept of Artemisia s.l. that includes Neopallasia, Crossostephium, Filifolium, Seriphidium, and Sphaeromeria. However, the phylogeny excludes Elachanthemum, Kaschgaria, and Stilnolepis from the Artemisia-group. Additionally, the monophyly of the four subgenera of Artemisia is also not supported, with the exception of subg. Dracunculus. Homogamous, discoid capitula appear to have arisen in parallel four to seven times, with the loss of ray florets. Thus capitular morphology is not a reliable taxonomic character, which traditionally has been one of the defining characters

    Book Reviews

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    Review of the following books: Revolutionary Outlaws: Ethan Allen and the Struggle for Independence on the Early American Frontier by Michael A. Bellesiles; The Salem Witch Crisis by Larry Gragg; Hard Times, Hard Men: Maine and the Irish, 1830-1860 by James H. Mundy; Keepers of Our Past: Local Historical Writing in the United States, 1820s-1930s by David J. Russo; Woodsmen and Whigs: Historic Images of Bangor, Maine by Abigail Ewing Zelz and Marily Zoidis; Bethel, Maine: An Illustrated History by Randall H. Bennett; Dearest Father: The Civil War Letters of Lt. Frank Dickerson, a Son of Belfast, Maine by H. Draper Hunt

    House price Keynesianism and the contradictions of the modern investor subject

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    This article conceptualises the marked downturn in UK house prices in the 2007-2009 period in relation to longer-term processes of national economic restructuring centred on a new model of homeownership. The structure of UK house prices has been impacted markedly by the Labour Government‟s efforts to ingrain a particular notion of financial literacy amid the move towards an increasingly asset-based system of welfare. New model welfare recipients and new model homeowners have thereby been co-constituted in a manner consistent with a new UK growth regime of „house price Keynesianism‟. However, the investor subjects who drive such growth are necessarily rendered uncertain as compared with the idealised image of Government policy because of their reliance on the credit-creating decisions of private financial institutions. The recent steep decline in UK house prices is explained here as an epiphenomenon of the disruptive effect on the idealised image caused by the dependence of investor subjects on pricing dynamics not of their making
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