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11.
There have been many studies of the link between the level of policing in an area and the behaviour of local drivers, but those that have been conducted in the United Kingdom were either small scale or were conducted many years ago. Consequently, a practical trial was carried out in London in May 2008 to investigate the effects of increasing the level of traffic policing in a busy urban area under modern conditions. Operation Radar ran for four weeks and increased the visible presence of police on a six mile stretch of the A23 in South London. Two teams of six officers and one sergeant were deployed in two shifts per weekday on the six mile route, using both static and mobile policing methods in a mixture of vehicles.This paper summarises the effects achieved, both in terms of the number of offences detected by the police and the effects on driver behaviour observed by a series of roadside surveys. These surveys measured vehicle speeds and drivers’ use of mobile phones and seatbelts. Vehicle speeds reduced systematically during the operation along the route and in surrounding areas, and some effects remained at least two weeks after the operation had finished. The survey data do not, however, show any positive effect of enforcement on the use of mobile phones or seatbelts.  相似文献   
12.
是否我们可以自己设计一下明日的花园,设计一下使生物多样性更加丰富的环境呢?请想象一下在一个世界里每个公民都有机会关注自己的微生境。从屋顶露台到停车场、从郊外花园到工业垃圾场——对于一只袋子来说,每一个空间都是不小的,即使只有一棵树及其相关的生态系统。与其面对日渐消减的生物多样性而感到困顿,  相似文献   
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Robert Morgan, lecturer in marketing, and Jackie Burnicle, of Cardiff Business School, provide a snapshot of how the external communication of housebuilding firms are addressed, and in addition, supply some sound foundation to much of the conjecture surrounding the issue of competitive forces in the industry.  相似文献   
15.
The purpose of this study was to provide an experimental test of the theory of change put forth by A. T. Beck, A. J. Rush, B. E Shaw, and G. Emery ( 1979 ) to explain the efficacy of cognitive-behavioral therapy (CT) for depression. The comparison involved randomly assigning 150 outpatients with major depression to a treatment focused exclusively on the behavioral activation (BA) component of CT, a treatment that included both BA and the teaching of skills to modify automatic thoughts (AT), but excluding the components of CT focused on core schema, or the full CT treatment. Four experienced cognitive therapists conducted all treatments. Despite excellent adherence to treatment protocols by the therapists, a clear bias favoring CT, and the competent performance of CT, there was no evidence that the complete treatment produced better outcomes, at either the termination of acute treatment or the 6-month follow-up, than either component treatment. Furthermore, both BA and AT treatments were just as effective as CT at altering negative thinking as well as dysfunctional attributional styles. Finally, attributional style was highly predictive of both short- and long-term outcomes in the BA condition, but not in the CT condition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
16.
Diabetic kidney disease (DKD) is the leading cause of kidney failure. RhoA/Rho-associated protein kinase (ROCK) signaling is a recognized mediator of its pathogenesis, largely through mediating the profibrotic response. While RhoA activation is not feasible due to the central role it plays in normal physiology, ROCK inhibition has been found to be effective in attenuating DKD in preclinical models. However, this has not been evaluated in clinical studies as of yet. Alternate means of inhibiting RhoA/ROCK signaling involve the identification of disease-specific activators. This report presents evidence showing the activation of RhoA/ROCK signaling both in vitro in glomerular mesangial cells and in vivo in diabetic kidneys by two recently described novel pathogenic mediators of fibrosis in DKD, activins and cell-surface GRP78. Neither are present in normal kidneys. Activin inhibition with follistatin and neutralization of cell-surface GRP78 using a specific antibody blocked RhoA activation in mesangial cells and in diabetic kidneys. These data identify two novel RhoA/ROCK activators in diabetic kidneys that can be evaluated for their efficacy in inhibiting the progression of DKD.  相似文献   
17.
Effective yet versatile synthetic strategies for size-tunable metal nanoclusters (NCs) are scarce. This has hampered the development of this unique class of nanomaterials. Here, a general protocol is reported for the synthesis of high-quality metal NCs protected by a variety of organic ligands (e.g., selenolate, thiolate, and phosphine) based on a miscible-solvent-assisted phase transfer between water and organic solution. This method is demonstrated to be facile, rapid (≤3 h), scalable (gram-scale), and versatile. The size of the selenolated and thiolated Au NCs can be tuned from Au10 to Au61 by simply varying the miscible solvent in proportions and types. The advantages of this method, such as quick phase separation and no need for purification treatment, enable real-time monitoring of metal NC growth within the NaBH4 reduction system. The results show that the size of Au NCs gradually increases with increasing valence electron count by a stepwise 2x e- hopping mechanism (x = 0–5), i.e., 0 e- → 2 e- → 4 e- → 8 e- → 18 e- → 22 e- → 32 e-.  相似文献   
18.
Rapid urbanisation in the South has contributed to the growth of informal housing on a large scale. South Africa’s experience is somewhat unusual in that the growth of informality appears to have taken the form of backyard shacks in established townships rather than free-standing shacks in squatter settlements. This is potentially important for household well-being (e.g. better access to services) and for the efficient functioning of urban areas. The paper develops a framework for assessing the impacts and applies it to the country’s leading metropolitan region, Gauteng. It finds that people are slightly better-off in backyards than in shacks elsewhere, although the wider benefits for urban areas are equivocal. In some respects backyard shacks are a stopgap for poor households desperate for somewhere to live. In other respects they represent a kind of prototype solution to the urban housing crisis. The government could do more to improve basic dwelling conditions and to relieve the extra pressure on local services.  相似文献   
19.
Ultrasensitive Pb2+ detection by glutathione-capped quantum dots   总被引:4,自引:0,他引:4  
Ali EM  Zheng Y  Yu HH  Ying JY 《Analytical chemistry》2007,79(24):9452-9458
Water-soluble and stable quantum dots (QDs), CdTe and CdZnSe, are applied for ultrasensitive Pb(2+) detection. These QDs are capped with glutathione (GSH) shells. GSH and its polymeric form, phytochelatin, are employed by nature to detoxify heavy metal ions. As a result of specific interaction, the fluorescence intensity of GSH-capped QDs is selectively reduced in the presence of heavy metal ions such as Pb(2+). The detection limit of Pb(2+) is found to be 20 nM due to the superior fluorescence properties of QDs. Detailed studies by spectroscopy, microscopy, and dynamic light scattering show that competitive GSH binding of Pb(2+) with the QD core changed both the surface and photophysical properties of the QDs. Fluorescence of QDs is quenched, and QD aggregation occurs. Coupling the GSH-capped QDs with a high-throughput detection system, we have developed a simple scheme for quick and ultrasensitive Pb(2+) detection without the need for additional electronic devices. In the presence of ionic mixtures, our system is still capable of Pb(2+) detection with a detection limit as low as 40 nM. The system only becomes less sensitive when the ionic mixture is present at a very high concentration (i.e., > or =50 microM).  相似文献   
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