2,356 research outputs found
Where concerned citizens perceive police as more responsive to troublesome teen groups: theoretical implications for political economy, incivilities and policing
The current investigation extends previous work on citizens\u27 perceptions of police performance. It examines the origins of between-community differences in concerned citizens\u27 judgments that police are responding sufficiently to a local social problem. The problem is local unsupervised teen groups, a key indicator for both the revised systemic social disorganization perspective and the incivilities thesis. Four theoretical perspectives predict ecological determinants of these shared judgments. Less perceived police responsiveness is anticipated in lower socioeconomic status (SES) police districts by both a political economy and a stratified incivilities perspective; more predominantly minority police districts by a racialized justice perspective; and in higher crime police districts by a proposed extension of Klinger\u27s ecology of policing model. The current work improves upon earlier conflicting work in this area in several ways; most importantly it distinguishes between the perceived need for police and perceived police responsiveness. Survey, census and crime data from Philadelphia were used. Results showed residents concerned about this problem and living in lower SES police districts or higher violent crime police districts judged police as less responsive. Results supported the political economy and stratified incivilities models and to a lesser extent the proposed extension of Klinger\u27s ecology of policing perspective. Implications for broader understandings of community variation in citizens\u27 reactions to police, and for national programmes to improve police responsiveness, were noted
Neighborhood Race and Nearby Race Affects Neighborhood Changes in Relative Status and Stability: Testing an Ecological Extension of the Neighborhood Projection Thesis
Current work tests an ecological extension of Ellen’s (2000a) neighborhood projection thesis which explains individual-level moving behavior in response to neighborhood racial composition. It posits that residents anticipate future erosions in local services and amenities based on current and expected future racial composition. The ecological extension tested here anticipates declines in relative neighborhood status and neighborhood residential stability where the population is more predominantly African American initially, or becomes more African American over a decade, or is initially surrounded by more predominantly African American neighborhoods. All three of these race effects have generated mixed results in earlier studies. Looking at a decade of change (1990 to 2000) for two mid-Atlantic central cities (Baltimore (MD) and Philadelphia (PA)), results in both cities confirmed that relative status was more likely to decline if adjoining neighborhoods were more predominantly African American initially, or if the neighborhood was becoming more predominantly African American during the period. The impacts of racial composition on stability changes were neither uniform across cities nor uniformly adverse. At least for neighborhood changes in status, results support the proposed extension of Ellen’s model to the neighborhood level, and underscored the spatial externalities arising from nearby populations of color
Region Spherical Harmonic Magnetic Modeling from Near-Surface and Satellite-Altitude Anomlaies
The compiled near-surface data and satellite crustal magnetic measured data are modeled with a regionally concentrated spherical harmonic presentation technique over Australia and Antarctica. Global crustal magnetic anomaly studies have used a spherical harmonic analysis to represent the Earth's magnetic crustal field. This global approach, however is best applied where the data are uniformly distributed over the entire Earth. Satellite observations generally meet this requirement, but unequally distributed data cannot be easily adapted in global modeling. Even for the satellite observations, due to the errors spread over the globe, data smoothing is inevitable in the global spherical harmonic presentations. In addition, global high-resolution modeling requires a great number of global spherical harmonic coefficients for the regional presentation of crustal magnetic anomalies, whereas a lesser number of localized spherical coefficients will satisfy. We compared methods in both global and regional approaches and for a case where the errors were propagated outside the region of interest. For observations from the upcoming Swarm constellation, the regional modeling will allow the production a lesser number of spherical coefficients that are relevant to the region of interes
The Texture of Surficial Sediments in Central Long Island Sound off Milford, Connecticut.
The purpose of this study was to determine the grain-size distributions and associated statistical parameters of the surficial sediment samples from central Long Island Sound off Milford, Connecticut. These grain-size data, which help to ground-truth a pre-existent sidescan sonar survey (Poppe and others, 1995a; Twichell and others, in press), will eventually be used to describe the sedimentary processes active in this portion of central Long Island Sound. Other potential uses for these textural data include benthic biologic studies that evaluate faunal distributions and relate them to habitats (Zajac and others, 1995), and geochemical studies involving the distribution, transport and deposition of pollutants (Moffett and others, 1994)
Mutations in DYNC2LI1 disrupt cilia function and cause short rib polydactyly syndrome.
The short rib polydactyly syndromes (SRPSs) are a heterogeneous group of autosomal recessive, perinatal lethal skeletal disorders characterized primarily by short, horizontal ribs, short limbs and polydactyly. Mutations in several genes affecting intraflagellar transport (IFT) cause SRPS but they do not account for all cases. Here we identify an additional SRPS gene and further unravel the functional basis for IFT. We perform whole-exome sequencing and identify mutations in a new disease-producing gene, cytoplasmic dynein-2 light intermediate chain 1, DYNC2LI1, segregating with disease in three families. Using primary fibroblasts, we show that DYNC2LI1 is essential for dynein-2 complex stability and that mutations in DYNC2LI1 result in variable length, including hyperelongated, cilia, Hedgehog pathway impairment and ciliary IFT accumulations. The findings in this study expand our understanding of SRPS locus heterogeneity and demonstrate the importance of DYNC2LI1 in dynein-2 complex stability, cilium function, Hedgehog regulation and skeletogenesis
Organic Carbon, Hydrogen, and Nitrogen Concentrations in Surficial Sediments from Western Long Island Sound, Connecticut and New York
Total organic carbon, hydrogen, and nitrogen (CHN) analyses were performed on 147 surficial sediment samples from study areas off the Norwalk Islands and Milford, Connecticut, in western Long Island Sound. The CHN data and gross lithologic descriptions of the sediments are reported herein. The concentrations of total organic carbon (TOC), hydrogen, and nitrogen in these samples average 1.54, 1.40, and 0.17 weight percent, respectively. The individual CHN concentrations vary inversely with grain size, with CHN values increasing with the percent fines. Increasing nutrient inputs and decreasing circulation cause TOC and nitrogen values to generally increase westward within the Sound. C/N molar elemental ratios suggest that, except for the shoreward northwestern corner of the Norwalk Islands survey site, marine phytoplankton are probably the primary source of sedimentary organic matter in the study areas. Concentrations of the sedimentary organic matter are significantly higher in the spring than in the late summer, suggesting that these concentrations vary seasonally
Relativistic quantum information and time machines
Relativistic quantum information combines the informational approach to
understanding and using quantum mechanics systems - quantum information - with
the relativistic view of the universe. In this introductory review we examine
key results to emerge from this new field of research in physics and discuss
future directions. A particularly active area recently has been the question of
what happens when quantum systems interact with general relativistic closed
timelike curves - effectively time machines. We discuss two different
approaches that have been suggested for modelling such situations. It is argued
that the approach based on matching the density operator of the quantum state
between the future and past most consistently avoids the paradoxes usually
associated with time travel.Comment: to appear in Contemporary Physic
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