844 research outputs found

    The Future as a Social Fact: The Analysis of Perceptions of the Future in Sociology

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    A small but growing share of sociological research recognizes the importance of perceptions of the future for explaining social outcomes. This article, taking a sociology of knowledge perspective, provides a systematic study of sociological scholarship dealing empirically with perceptions of the future. It is based on a qualitatively driven mixed methods analysis of 571 sociological research articles published between 1950 and 2019 and distinguishes between three clusters of scholarship: in the first cluster authors consider future orientations as either dependent or independent variable; in the second cluster they analyze the multifaceted ways in which actors imagine the future; and in the third cluster they are interested in the politically contested construction and diffusion of future orientations. By investigating these clusters, the article demonstrates how sociologists pay attention to future orientations in a broad spectrum of sociological fields, using a variety of methods and asking a wide set of questions about assessments of the future. The future is increasingly a realm of sociological analysis. We show how this field of research is structured and has developed over time. Elaborating on different facets of research that so far operate largely in isolation from each other, we aim to contribute to the development of the field. Sociology could benefit from more systematically integrating perceptions of the future – as they are reflected in actor expectations, aspirations, and future beliefs – into the discipline's empirical investigations and explanatory models and from integrating the existing knowledge on these issues better.1. Introduction 2. The future in sociology 3. Mapping the development of a research field: data and methods 4. Emergence and growth of the research field 5. Diversification I: Empirical objects and sociological subfields 6. How is the future studied? The epistemological structure of the research field 7. Studying the future as a social fact: A three-clustered research field 7.1 Studying the future as a variable: The sources and effects of aspirations 7.2 Studying images of the future: What does the future look like? 7.3 Studying the contest for the future: How is the future constructed? 8. Diversification II: The emergence of the three research clusters 9. What journals? Important outlets of the research field 10. Conclusion and future research paths Appendix Acknowledgements Reference

    Maximal uniform convergence rates in parametric estimation problems

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    This paper considers parametric estimation problems with independent, identically nonregularly distributed data. It focuses on rate efficiency, in the sense of maximal possible convergence rates of stochastically bounded estimators, as an optimality criterion, largely unexplored in parametric estimation. Under mild conditions, the Hellinger metric, defined on the space of parametric probability measures, is shown to be an essentially universally applicable tool to determine maximal possible convergence rates. These rates are shown to be attainable in general classes of parametric estimation problems

    High Proper Motion Stars in the Vicinity of Sgr A*: Evidence for a Supermassive Black Hole at the Center of Our Galaxy

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    Over a two year period (1995-1997), we have conducted a diffraction-limited imaging study at 2.2 microns of the inner 6"x6" of the Galaxy's central stellar cluster using the Keck 10-m telescope. The K band images obtained reveal a large population of faint stars. We use an unbiased approach for identifying and selecting stars to be included in this proper motion study, which results in a sample of 90 stars with brightness ranging from K=9-17 and velocities as large as 1,400+-100 km/sec. Compared to earlier work (Eckart et al. 1997; Genzel et al. 1997), the source confusion is reduced by a factor of 9, the number of stars with proper motion measurement in the central 25 arcsec^2 of our galaxy is doubled, and the accuracy of the velocity measurements in the central 1 arcsec^2 is improved by a factor of 4. The peaks of both the stellar surface density and the velocity dispersion are consistent with the position of the unusual radio source and blackhole candidate, Sgr A*, suggesting that Sgr A* is coincident (+-0."1) with the dynamical center of the Galaxy. As a function of distance from Sgr A*, the velocity dispersion displays a falloff well fit by Keplerian motion about a central dark mass of 2.6(+-0.2)x10^6 Mo confined to a volume of at most 10^-6 pc^3, consistent with earlier results. Although uncertainties in the measurements mathematically allow for the matter to be distributed over this volume as a cluster, no realistic cluster is physically tenable. Thus, independent of the presence of Sgr A*, the large inferred central density of at least 10^12 Mo/pc^3, which exceeds the volume-averaged mass densities found at the center of any other galaxy, leads us to the conclusion that our Galaxy harbors a massive central black hole.Comment: 19 pages, 8 figures, accepted for publications in the Astrophysical Journa

    Social Cognitive Factors Associated with Sharing Overt and Relational Cyberaggression Digitally

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    Cyberaggression is a substantial problem for college-aged students. The purpose of this cross-sectional study was to examine associations between social cognitive factors and digitally sharing one’s own and others’ overt and relational cyberaggressive material among college students. Social cognitive factors included cyber moral disengagement and facets of cognitive autonomy, including comparative validation, voicing opinions, and evaluative thinking. A convenience sample of 437 college students from a medium-sized US university completed an online survey about cyber aggression and related social cognitive factors. Results from a structural equation model, controlling for gender, showed that cyber moral disengagement was positively associated with sharing own and others’ overt and relational cyberaggressive material. Sharing one’s own and others’ relational cyberaggression was positively associated with comparative validation but was negatively associated with evaluative thinking. The present research reinforces prior links between moral disengagement and cyberaggression while examining other social cognitive factors associated with cyberaggression and assisting cyberaggression perpetrators

    Relationship of balance to function independence in stroke survivors

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    Cerebral vascular disease is the primary cause of permanent disability in Portugal. Impaired stability is considered an important feature after stroke as it is related with higher risk of falls and functional dependence. Physiotherapy intervention usually starts early after stroke in order to direct motor recovery and help patients to improve their ability to perform activities of daily living (ADL). Purpose: to investigate the relationship of balance to functionality in acute stroke patients. Methods: 16 subjects (8 women and 8 men), mean age 63,62 ± 2,16y, with unilateral ischemic stroke in the middle cerebral artery territory, who were admitted to physiotherapy department of Fernando Fonseca Hospital in Portugal, within the first month after stroke were recruited to participate in this study. All subjects have no cognitive impairment according to Mini Mental State, no history of lower extremity orthopedic problems and no other disease that could interfere with treatments. All patients gave their inform consent to participate in this study. Subjects were assessed with the Modified Barthel Index (MBI) and the Berg Balance Scale (BBS).Supported by Portuguese Foundation for Science and Technology Grant SFRH/PROTEC/49675/2009

    Understanding Scintillation of Intraday Variables

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    Intraday Variability of compact extragalactic radio sources can be interpreted as quenched scintillation due to turbulent density fluctuations of the nearby ionized interstellar medium. We demonstrate that the statistical analysis of IDV time series contains both information about sub-structure of the source on the scale of several 10 micro-arcsec and about the turbulent state of the ISM. The source structure and ISM properties cannot be disentangled using IDV observations alone. A comparison with the known morphology of the `local bubble' and the turbulent ISM from pulsar observations constrains possible source models. We further argue that earth orbit synthesis fails for non-stationary relativistic sources and no reliable 2D-Fourier reconstruction is possible.Comment: 4 pages, 3 figures, Proceedings of the 6th European VLBI Network Symposium, Ros E., Porcas R.W., Lobanov, A.P., & Zensus, J.A. (eds), MPIfR, Bonn, German

    Muscle strength, balance and functional independence in persons with stroke

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    Cerebral vascular disease is one of the main causes of morbidity, disability and mortality in developed countries. Problems with movement control are frequent after stroke. Lower limb weakness and impaired balance are common problems that are related with the risk of falls and are likely to interfere with the ability to perform daily life activities. Physiotherapy intervention usually starts early after stroke and addresses impairments related to movement and posture in order to improve motor recovery and restore function. Purpose: to investigate the relationship between knee muscle strength, balance and functional independence within the first month after stroke

    Subarcsecond Submillimeter Imaging of the Ultracompact HII Region G5.89-0.39

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    We present the first subarcsecond submillimeter images of the enigmatic ultracompact HII region (UCHII) G5.89-0.39. Observed with the SMA, the 875 micron continuum emission exhibits a shell-like morphology similar to longer wavelengths. By using images with comparable angular resolution at five frequencies obtained from the VLA archive and CARMA, we have removed the free-free component from the 875 micron image. We find five sources of dust emission: two compact warm objects (SMA1 and SMA2) along the periphery of the shell, and three additional regions further out. There is no dust emission inside the shell, supporting the picture of a dust-free cavity surrounded by high density gas. At subarcsecond resolution, most of the molecular gas tracers encircle the UCHII region and appear to constrain its expansion. We also find G5.89-0.39 to be almost completely lacking in organic molecular line emission. The dust cores SMA1 and SMA2 exhibit compact spatial peaks in optically-thin gas tracers (e.g. 34SO2), while SMA1 also coincides with 11.9 micron emission. In CO(3-2), we find a high-velocity north/south bipolar outflow centered on SMA1, aligned with infrared H2 knots, and responsible for much of the maser activity. We conclude that SMA1 is an embedded intermediate mass protostar with an estimated luminosity of 3000 Lsun and a circumstellar mass of ~1 Msun. Finally, we have discovered an NH3 (3,3) maser 12 arcsec northwest of the UCHII region, coincident with a 44 GHz CH3OH maser, and possibly associated with the Br gamma outflow source identified by Puga et al. (2006).Comment: 41 pages, 11 figures, published in The Astrophysical Journal (2008) Volume 680, Issue 2, pp. 1271-1288. An error in the registration of the marker positions in Figure 11 has been corrected in this versio

    Multi-frequency Study of Intraday Variable Sources

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    Intraday variability (IDV) of compact extragalactic radio sources is a complex phenomenon and shows a wavelength dependent mixture of refractive interstellar scintillation (RISS) (dominant at long cm-wavelengths) and source-intrinsic effects (dominant at shorter wavelengths). Detailed investigations of individual sources and new high frequency observations suggest a source-intrinsic contribution to the IDV pattern at least in some sources. However, the sizes of intraday variable sources at cm-wavelength are typically smaller than the scattering size set by the ISM in our galaxy and scintillation must be present, too. We present new IDV observations in different regimes (from cm to sub-mm wavelengths) and show how such multi-frequency study can be used as powerful instrument to describe different aspects of IDV.Comment: 4 pages. Proceedings of the 6th European VLBI Network Symposium. Ros E., Porcas R.W., Lobanov A.P. and Zensus J.A. (eds.). June 25th-28th 2002, Bonn, German
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