647 research outputs found

    Ice Particles Trapped by Temperature Gradients at mbar Pressure

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    In laboratory experiments we observe that ice particles (\leq100 \mu m) entrained in a low pressure atmosphere (~1 mbar) get trapped by temperature gradients between three reservoirs at different tempertature. Confining elements are a peltier element at 250 K (bottom), a liquid nitrogen reservoir at 77 K (top) and the surrounding vacuum chamber at 293 K. Particle levitation and trapping is modeled by an interplay of thermophoresis, photophoresis and gravity. A number of ice particles are trapped simultaneously in close spatial distance to each other at least up to minutes and are accessible for further experiments.Comment: Published in Review of Scientific Instruments 82, 2011, 4 pages, 6 figure

    Community Policing: Broken Windows, Community Building, and Satisfaction with the Police

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    The concept of community policing dominates the law enforcement profession today. One would be hard pressed to find an advertisement for a police chief’s position that does not require a thorough understanding of this method of policing. Like the Kansas City preventive patrol experiment and the Rand report on the criminal investigation process, the call for community policing has led to dramatic changes in the way that police carry out their responsibilities. In spite of its popularity, there have been a number of challenges to community policing from social scientists who are particularly concerned about the ‘broken windows’ model of policing. These challenges have not been received well by the law enforcement community, which argues that sociologists are wedded to the idea that crime is caused by the structural features of capitalist society, including economic injustice, racism, and poverty. The purpose of this article is to bridge the gap between these two positions. Yes, there is a place for community policing, and, yes, social problems do contribute to crime. The article starts by reviewing the development of community policing in the United States. An analysis of the theoretical constructs that support community policing then follows. Finally, we argue that there is sound theoretical evidence to support community policing, particularly those programmes that improve citizen satisfaction with the manner in which police carry out their responsibilities

    Comparison of Different Parallel Implementations of the 2+1-Dimensional KPZ Model and the 3-Dimensional KMC Model

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    We show that efficient simulations of the Kardar-Parisi-Zhang interface growth in 2 + 1 dimensions and of the 3-dimensional Kinetic Monte Carlo of thermally activated diffusion can be realized both on GPUs and modern CPUs. In this article we present results of different implementations on GPUs using CUDA and OpenCL and also on CPUs using OpenCL and MPI. We investigate the runtime and scaling behavior on different architectures to find optimal solutions for solving current simulation problems in the field of statistical physics and materials science.Comment: 14 pages, 8 figures, to be published in a forthcoming EPJST special issue on "Computer simulations on GPU

    Calcium Channel Blocker D-\u3cem\u3ecis\u3c/em\u3e-Diltiazem Does Not Slow Retinal Degeneration in the \u3cem\u3ePDE6B\u3c/em\u3e Mutant \u3cem\u3ercd1\u3c/em\u3e Canine Model of Retinitis Pigmentosa

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    Purpose: D-cis-diltiazem, a calcium channel blocker, has been reported to enhance photoreceptor survival in the rd mouse, a model of retinitis pigmentosa (RP) resulting from mutation of the PDE6B gene. We tested the hypothesis that diltiazem treatment would similarly rescue the canine rcd1 model of RP, which is also caused by a null mutation in the PDE6B gene. Methods: D-cis-diltiazem was delivered orally twice daily to rcd1 affected dogs beginning at 4 weeks of age; untreated age-matched rcd1 dogs served as controls. At 14 weeks, electroretinograms (ERG) were performed on all animals; 14 dogs were euthanized at this age, and 2 dogs at 25 weeks of age. Eyes were enucleated, fixed, and processed for routine histological examination. Results: No significant differences were found in ERG or histopathologic parameters between diltiazem-treated and untreated rcd1 dogs. Neither rcd1 group showed a rod b-wave; ERGs evoked by single white flashes (dark- or light-adapted) and flicker were also identical between groups. Similarly, treated and untreated animals did not differ in the degree of preservation of the photoreceptor layer, confirmed in cell counts within the outer nuclear layer. Conclusions: Treatment of rcd1 affected dogs with D-cis-diltiazem did not modify the photoreceptor disease when results were assessed using either ERG or histopathologic criteria. The positive photoreceptor-rescue effect of calcium channel blockers reported in the rd mouse was thus not generalizable to another species with retinal degeneration due to mutation in the PDE6B gene. Caution needs to be exerted in extrapolation to the comparable human forms of RP

    Community‐Engaged Neighborhood Revitalization and Empowerment: Busy Streets Theory in Action

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    Busy streets theory predicts that engaging residents in physical revitalization of neighborhoods will facilitate community empowerment through the development of sense of community, social cohesion, collective efficacy, social capital, and behavioral action. Establishing safe environments fosters positive street activity, which reinforces neighborhood social relationships. A community‐engaged approach to crime prevention through environmental design (CE‐CPTED) is one promising approach to creating busy streets because it engages residents in collaborative interactions to promote safer environments. Yet, few researchers have studied how CE‐CPTED may be associated with busy streets. We interviewed 18 residents and stakeholders implementing CE‐CPTED in Flint, Michigan. We studied three neighborhoods with different levels of resident control over CE‐CPTED. Participants described how CE‐CPTED implementation affected their neighborhood. Participants from all three neighborhoods reported that CE‐CPTED was associated with positive street activity, sense of community, and collective efficacy. Participants from neighborhoods with higher resident control of CE‐CPTED reported more social capital and behavioral action than those from neighborhoods with less resident control. Our findings support busy streets theory: Community engagement in neighborhood improvement enhanced community empowerment. CE‐CPTED that combines physical revitalization with resident engagement and control creates a potent synergy for promoting safe and healthy neighborhoods.HighlightsBusy streets theory supported in qualitative study of neighborhoods in a rust belt city.Community engaged neighborhood improvement enhances psychological empowerment.Resident control of neighborhood revitalization results in most empowered outcomes of busy streets.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154635/1/ajcp12358_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154635/2/ajcp12358.pd

    Canine \u3cem\u3eRD3\u3c/em\u3e Mutation Establishes Rod-Cone Dysplasia Type 2 (\u3cem\u3ercd2\u3c/em\u3e) as Ortholog of Human and Murine \u3cem\u3erd3\u3c/em\u3e

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    Rod-cone dysplasia type 2 (rcd2) is an autosomal recessive disorder that segregates in collie dogs. Linkage disequilibrium and meiotic linkage mapping were combined to take advantage of population structure within this breed and to fine map rcd2 to a 230-kb candidate region that included the gene C1orf36 responsible for human and murine rd3, and within which all affected dogs were homozygous for one haplotype. In one of three identified canine retinal RD3 splice variants, an insertion was found that cosegregates with rcd2 and is predicted to alter the last 61 codons of the normal open reading frame and further extend the open reading frame. Thus, combined meiotic linkage and LD mapping within a single canine breed can yield critical reduction of the disease interval when appropriate advantage is taken of within-breed population structure. This should permit a similar approach to tackle other hereditary traits that segregate in single closed populations

    Reassurance Policing and Signal Crimes

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    A reassurance function for policing was first considered by American psychologist Charles Bahn (1974: 338) as “feelings of safety that a citizen experiences when he knows that a police officer or patrol car is nearby.” This idea was taken forward in Britain by Martin Innes and colleagues in the early 2000s through the development of a signal crimes perspective. At this time, British policing implemented a National Reassurance Policing Programme (NRPP) where local policing priorities were decided through consultation with local communities. The impact of reassurance policing has since spread and the approach has also been considered in Australia, Belgium, the Netherlands, and Sweden. In this entry, the background to reassurance policing is considered with particular reference to the work of Charles Bahn and Martin Innes and colleagues. The development of a policy of reassurance policing in Britain is also examined. The successes and limitations of the approach are considered and three main issues identified: that reassurance needs to be a consideration for all policing; that increases in visible patrol need to be questioned (especially at a time of budget restraint); and that reassurance policing has the potential to be a model of democratic policing, but only if consultation is truly inclusive, for instance, including those that have been victimized and groups that have been targets of police activity such as young people, the homeless, and other minority and marginalized groups

    Identical Mutation in a Novel Retinal Gene Causes Progressive Rod-Cone Degeneration in Dogs and Retinitis Pigmentosa in Humans

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    Progressive rod–cone degeneration (prcd) is a late-onset, autosomal recessive photoreceptor degeneration of dogs and a homolog for some forms of human retinitis pigmentosa (RP). Previously, the disease-relevant interval was reduced to a 106-kb region on CFA9, and a common phenotype-specific haplotype was identified in all affected dogs from several different breeds and breed varieties. Screening of a canine retinal EST library identified partial cDNAs for novel candidate genes in the disease-relevant interval. The complete cDNA of one of these, PRCD, was cloned in dog, human, and mouse. The gene codes for a 54-amino-acid (aa) protein in dog and human and a 53-aa protein in the mouse; the first 24 aa, coded for by exon 1, are highly conserved in 14 vertebrate species. A homozygous mutation (TGC → TAC) in the second codon shows complete concordance with the disorder in 18 different dog breeds/breed varieties tested. The same homozygous mutation was identified in a human patient from Bangladesh with autosomal recessive RP. Expression studies support the predominant expression of this gene in the retina, with equal expression in the retinal pigment epithelium, photoreceptor, and ganglion cell layers. This study provides strong evidence that a mutation in the novel gene PRCD is the cause of autosomal recessive retinal degeneration in both dogs and humans

    Long-Term Restoration of Rod and Cone Vision by Single Dose rAAV-Mediated Gene Transfer to the Retina in a Canine Model of Childhood Blindness

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    The short- and long-term effects of gene therapy using AAV-mediated RPE65 transfer to canine retinal pigment epithelium were investigated in dogs affected with disease caused by RPE65 deficiency. Results with AAV 2/2, 2/1, and 2/5 vector pseudotypes, human or canine RPE65 cDNA, and constitutive or tissue-specific promoters were similar. Subretinally administered vectors restored retinal function in 23 of 26 eyes, but intravitreal injections consistently did not. Photoreceptoral and postreceptoral function in both rod and cone systems improved with therapy. In dogs followed electroretinographically for 3 years, responses remained stable. Biochemical analysis of retinal retinoids indicates that mutant dogs have no detectable 11-cis-retinal, but markedly elevated retinyl esters. Subretinal AAV-RPE65 treatment resulted in detectable 11-cis-retinal expression, limited to treated areas. RPE65 protein expression was limited to retinal pigment epithelium of treated areas. Subretinal AAV-RPE65 vector is well tolerated and does not elicit high antibody levels to the vector or the protein in ocular fluids or serum. In long-term studies, wild-type cDNA is expressed only in target cells. Successful, stable restoration of rod and cone photoreceptor function in these dogs has important implications for treatment of human patients affected with Leber congenital amaurosis caused by RPE65 mutations

    The state of interprofessional collaboration in Northern Italy: a mixed methods study.

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    Abstract Health care systems are facing continual reorganizations in response to scientific and technological innovations as well as financial constraints. Simultaneously the rising prevalence of chronic diseases call for a kind of health care organization in which interprofessional collaboration (IPC) functions on a high level. This article describes a research project that aims to generate an empirical account of the current state of IPC in the South Tyrolean Health Trust, located in a bilingual region in northern Italy. The study will employ a sequential mixed methods' design. A survey will be followed by individual and focus group interviews. An innovative aspect of the study is that it will include participants from six different health professions (dieticians, nurses, occupational therapists, physicians, physiotherapists, and speech therapists). Qualitative data analysis will draw on the negotiated order/structural ordering approach and on the social world/arena perspective. The results are expected to generate specific recommendations to improve IPC in the South Tyrolean Health Trust and inform further research
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