2,059 research outputs found

    Are U.S. Congregations Patching the Social Safety Net? Trends from 1998 to 2012

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    As social services become increasingly privatized amid a federal policy environment that provides a means-tested, temporary social safety net, there is potential for a larger contribution by congregations as social service providers. Using data from a nationally representative sample of religious congregations collected in 1998, 2006, and 2012, we examine whether congregations have increased service activity over time, and whether provision varies by the congregation’s community-level context. We find that post-Great Recession, congregations are more likely to engage in broad social services and in “core” services that address basic economic needs. Congregations in high-poverty neighborhoods were less likely to provide services in 1998 than congregations in low-poverty neighborhoods; after the recession, not only are significantly more congregations in high-poverty neighborhoods providing services than in 1998, they have closed the gap with congregations in low-poverty neighborhoods and are equally likely to be providing any services regardless of neighborhood poverty. Our findings highlight the importance of service measurement to determine the prevalence of congregation-level service provision and suggest that congregational service provision may be a substantial yet inadequate substitute for the public safety net

    Finding Efficient Collective Variables: The Case of Crystallization

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    Several enhanced sampling methods such as umbrella sampling or metadynamics rely on the identification of an appropriate set of collective variables. Recently two methods have been proposed to alleviate the task of determining efficient collective variables. One is based on linear discriminant analysis, the other on a variational approach to conformational dynamics, and uses time-lagged independent component analysis. In this paper, we compare the performance of these two approaches in the study of the homogeneous crystallization of two simple metals. We focus on Na and Al and search for the most efficient collective variables that can be expressed as a linear combination of X-ray diffraction peak intensities. We find that the performances of the two methods are very similar. However, the method based on linear discriminant analysis, in its harmonic version, is to be preferred because it is simpler and much less computationally demanding

    Visual Form of Alzheimer\u27s Disease and its Response to Anticholinesterase Therapy

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    In a 60-Year-Old Woman with the Visual Variant of Alzheimer\u27s Disease, Single Photon Emission Computed Tomography Abnormalities Were Most Marked in the Parieto-Occipital Regions of the Brain. after Treatment with Donepezil, Improvement is Noted on Neuropsychological Testing and on Brain SPECT, Including Increased Perfusion (Metabolism) in the Occipital Lobes

    Voltage-independent SK-channel dysfunction causes neuronal hyperexcitability in the hippocampus of Fmr1 knock-out mice

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    Neuronal hyperexcitability is one of the major characteristics of fragile X syndrome (FXS), yet the molecular mechanisms of this critical dysfunction remain poorly understood. Here we report a major role of voltage-independent potassium (

    Testate amoebae as palaeohydrological proxies in Sürmene Aǧaçbaşi Yaylasi Peatland (Northeast Turkey)

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    Testate amoebae as palaeohydrological proxies in sürmene ağaçbaşi yaylasi peatland (northeast Turkey) Testate amoebae are unicellular micro-organisms whose hydrological sensitivity and good preservation in peats make them valuable proxies for past peatland surface wetness, and therefore climate. Previous testate amoebae transfer functions have been spatially restricted with no studies from Asia. To derive a transfer function, a sequence of samples was extracted from an ombrotrophic peatland in Turkey and amoebae counted. The internal structure of the data was explored using principal components analysis and relationships with the environmental data tested by redundancy analyses. Transfer function models were developed using a variety of techniques. As in other regions, depth to water table is the most important control on amoebae community composition. Transfer function performance was initially poor, primarily due to the inclusion of samples from areas of the site that had been heavily affected by peat cutting and had distinctly different amoebae communities. Model performance is improved by selective sample exclusion, reducing jack-knifed root mean square error of prediction to 7.1 cm. The model was tested using an initial palaeoecological data-set. Overlap with the training set was limited, although a hydrological reconstruction using this model produces similar results to a transfer function derived from northern European peatlands. This study provides the first testate amoebae transfer function from Asia and demonstrates that hydrological preferences of many of the key taxa are consistent across a large area of the Northern Hemisphere. The transfer function will allow detailed palaeoclimate reconstruction from this peatland, adding to our knowledge of Holocene climatic change in southwest Asia

    Isolated Wetlands - The Groundwater Connection

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    2012 S.C. Water Resources Conference - Exploring Opportunities for Collaborative Water Research, Policy and Managemen

    Periodic optical variability and debris accretion in white dwarfs: a test for a causal connection

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    Recent Kepler photometry has revealed that about half of white dwarfs (WDs) have periodic, low-level (~ 1e-4 - 1e-3), optical variations. Hubble Space Telescope (HST) ultraviolet spectroscopy has shown that up to about one half of WDs are actively accreting rocky planetary debris, as evidenced by the presence of photospheric metal absorption lines. We have obtained HST ultraviolet spectra of seven WDs that have been monitored for periodic variations, to test the hypothesis that these two phenomena are causally connected, i.e. that the optical periodic modulation is caused by WD rotation coupled with an inhomogeneous surface distribution of accreted metals. We detect photospheric metals in four out of the seven WDs. However, we find no significant correspondence between the existence of optical periodic variability and the detection of photospheric ultraviolet absorption lines. Thus the null hypothesis stands, that the two phenomena are not directly related. Some other source of WD surface inhomogeneity, perhaps related to magnetic field strength, combined with the WD rotation, or alternatively effects due to close binary companions, may be behind the observed optical modulation. We report the marginal detection of molecular hydrogen in WD J1949+4734, only the fourth known WD with detected H_2 lines. We also re-classify J1926+4219 as a carbon-rich He-sdO subdwarf.Comment: MNRAS, in pres
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