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The negative impact of vacant and abandoned housing in city neighborhoods is extreme, affecting health and quality of life, promoting violence, and leading to further abandonment. One approach to addressing abandoned housing is to intervene with low-cost interventions that provide a visual sense of ownership. We tested whether a low-cost remediation of abandoned and vacant houses or a trash cleanup intervention would make a noticeable difference in the levels of nearby disrepair, disorder, and public safety. The abandoned housing remediation and trash cleanup interventions were a test of compliance with municipal ordinances. We used an experimental design to test the causal effects of the ordinances and because the scale of abandonment was too large to provide treatment to all abandoned houses in the city. We used systematic social observation methods to rate changes in disrepair, disorder, and litter at housing sites and on the city blocks they were located and police-reported data on gun violence and illegal substance use. Our experimental design allowed us to see whether observed disrepair, disorder, and public safety improved after working windows and doors were installed on abandoned houses compared with a trash cleanup around properties or a no-intervention control condition. Our results showed significant changes in observed disrepair, disorder, and gun violence and illustrate the benefits of experimental evaluations of place-based changes to the built environment. Improving compliance with ordinances to remediate abandoned housing can make a noticeable difference in disrepair in neighborhoods and contribute to improved public safety. We illustrate how planners can use field experiments in partnership with city agencies, nonprofit community groups, and local universities to discover novel approaches to advance place-based changes to the built environment that can help economically disadvantaged communities abate problems of physical disorder. [ABSTRACT FROM AUTHOR]

The research literature of supply chain risk and resilience is at a critical developmental stage. Studies have established the importance of these topics both to researchers and practitioners. They also have identified factors contributing to risk, the impact of risk and disruptions on performance, and the strategies and tactics used to build the capacity for supply chain resilience. Although these efforts can provide support for constructing a theory of risk and resilience, researchers are currently restricted in their ability to build such a theory by the difficulty of collecting the necessary data. This paper contributes to this literature development effort by summarising prior research reviews and developing a three-component framework aimed at helping researchers to build better theories. This is accomplished through combining structured experimental design with discrete-event simulations of supply chains. The result is a methodology that allows researchers to develop better understanding of the factors that link a disruption to its impact on supply chain performance through both direct and interaction effects. Following the methodology development, the paper concludes with an example using the factors of shock interarrival time, supply chain connectivity and buffer stocks to illustrate the potential for contributing to the theory-building process. [ABSTRACT FROM AUTHOR]

For modern electrical rail systems, the pantograph-catenary dynamic performance is one of the most critical challenges. Too much fluctuation in contact forces leads to either accelerated wear of the contacting components or losses of contact and, consequently, arcing. In this work, inertance-integrated pantograph damping systems are investigated with the objective of reducing the contact force standard deviation. Firstly, a multibody pantograph model is developed with its accuracy compared with experimental data. The model is improved through the calibration of the pantograph head suspension parameters and the introduction of both non-ideal joint and flexibility effects. Using the calibrated model, beneficial inertance-integrated damping systems are identified for the pantograph suspension. The results show that the configuration with one inerter provides the best performance among other candidate layouts and contends a 40% reduction of the maximum standard deviation of the contact force over the whole operating speed range in the numerical modelling scenario analysed. Considering the identified configuration, time-domain analysis and modal analysis are investigated. It has been shown that the achieved improvement is due to the fact that with the beneficial inertance-integrated damping system, the first resonance frequency of the pantograph system coincides with the natural frequency of the catenary system. [ABSTRACT FROM AUTHOR]

Traditional simulation modelling focuses upon the analysis of steady-state data. This focus may not be appropriate, however, for the study of transient responses – data reflecting some form of disruption or change in the system norms. Transient responses are often encountered when dealing with new product introductions, changes in production systems, or supply chain disruptions. In these situations, it is the transient response, how the system responds to these changes as well as the tactics and strategies used to deal with these changes, that tend to be of the greatest interest. Unfortunately, current approaches that focus on analysing such responses are limited. This paper introduces a new approach for analysing transient responses – one that merges outlier detection, a time series analysis tool, with simulation modelling. This combined approach allows the researcher to identify those factors that have the greatest impact upon operations during these transient conditions. Using a simulated supply chain disruption to illustrate the potential of the approach, it is shown that the new approach expands the applicability of simulation and enables certain types of problems to be investigated with confidence not previously provided. [ABSTRACT FROM PUBLISHER]

We here describe and name a new skipper butterfly in the genus Vettius Godman, 1901, currently known from two sites, one in Costa Rica and the other in Panama. Based on molecular data, Vettius mitsuko Nakahara, Nakamura & MacDonald, n. sp. is recovered as a sister to the type species of Vettius, Papilio phyllus Cramer, 1777. DNA sequence data further indicate V. chagres Nicolay, 1973 to be another closely related species, a relationship consistent with their phenotypic resemblance. The rather small genetic divergence between the two taxa and apparent allopatry might suggest a subspecific rank for V. mitsukon. sp. instead. However, further evidence from morphology, genetic data and ecology supports our hypothesis of species-level distinction. [ABSTRACT FROM AUTHOR]

Indian Prime Ministers occupy the pinnacle of India's government, national security hierarchy, and nuclear command and control infrastructure, which allows them to make decisions that transform Indian nuclear strategy. However, within India's nuclear decision-making bureaucracy, other actors including India's nuclear scientists and engineers, the military, and democratic processes can also adjust Indian nuclear strategy which creates rivalry. This article argues that the Indian Prime Minister's position gives them the ability to influence and direct these various domestic political actors to make a nuclear strategy that suits the Prime Minister's interests. But as bureaucratic actors actually translate the Prime Minister's directions into policy, it results in influence often falling short of control in setting nuclear strategy. Applying a bureaucratic model to the making of nuclear strategy, the article's findings suggest that Prime Ministers have purposefully guided and overseen India's post-Pokhran-II nuclear strategy beyond a "minimal" credible deterrent outlined in its 1999 official nuclear doctrine. [ABSTRACT FROM AUTHOR]

Various methodological approaches to constructing external and internal benchmarks have been applied to estimate racial bias in police stop, question, and frisk (SQF) patterns. We apply an external benchmark of the race of the residential population and an internal benchmark of similarly-situated stops to estimate if racial disparities in New York City SQF data were impacted by the Floyd, et al. v. City of New York court settlement. We find that after the settlement, the racial composition of census tracts were no longer significant predictors of the stop rate after controlling for reported crime, socioeconomic factors, and police precincts. We further find that differences in SQF outcomes and hit rates between Blacks and Hispanics and similarly-situated others diminished substantially after the settlement. These findings suggest that court reforms may be an effective method for reducing racial disparities in SQF patterns. [ABSTRACT FROM AUTHOR]

The current study builds on prior research examining racial disparities in sentencing. Entropy weighting is introduced as a new method for estimating racial disparities that has several advantages over traditionally used methods. Entropy weighting is compared to regression and propensity score methods in estimating Black-White disparities in incarceration sentences. Although all methods find non-significant racial disparities in incarceration sentences, regression and propensity score methods underestimate disparities in incarceration sentence lengths. Entropy weighting provides comparable estimates to propensity score methods, but assures that the samples are identical on all covariates aside from race. The method offers researchers a useful and flexible approach for estimating racial disparities in criminal justice, and its use may lead to alternative conclusions about the size and presence of racial disparities in sentencing. [ABSTRACT FROM AUTHOR]

This article examines the implications of Scottish independence for the UK's nuclear posture. It is argued here that a vote for independence will critically undermine this posture. Since the UK nuclear force operates entirely out of Scotland, and since the Scottish government continues to assert its intention to see nuclear weapons removed from an independent Scotland, it is overwhelmingly likely that a ‘Yes’ vote will prompt a demand for the drawdown of the UK nuclear force in Scotland. If it wished to maintain its nuclear capability, the UK government would then have to make alternative basing arrangements. It is argued here that a host of legal, financial and political difficulties may preclude any such relocation and that Downing Street may ultimately be left with little option but to surrender the UK's nuclear capability. This article concludes that far from weakening the UK, a surrendering of its nuclear posture would result in a stronger and more functional UK military footprint and would bolster the UK's standing in the international arena. [ABSTRACT FROM PUBLISHER]

Business improvement districts (BIDs) have been lauded and criticized for their special services provisions that putatively create community economic development environments in urban areas. Few studies have examined how specific BID functions operate within the larger context of community environments. This study describes BIDs in Los Angeles and examines whether their priorities align with underlying community conditions and economic development concerns. Relying on multiple sources of data, we find that there appears to be notable diversity in the budgets and expenditures of BIDs, some of which align with observed community conditions. BID operational priorities are associated with the environments in which they are situated. There is little evidence that BID priorities are universally focused on a single set of interests. The political economy of these organizations within their community context is critical to understanding their operations, appeal, and controversy. [ABSTRACT FROM AUTHOR]

Allegations of racially biased policing are a contentious issue in many communities. Processes that flag potential problem officers have become a key component of risk management systems at major police departments. We present a statistical method to flag potential problem officers by blending three methodologies that are the focus of active research efforts: propensity score weighting, doubly robust estimation, and false discovery rates. Compared with other systems currently in use, the proposed method reduces the risk of flagging a substantial number of false positives by more rigorously adjusting for potential confounders and by using the false discovery rate as a measure to flag officers. We apply the methodology to data on 500,000 pedestrian stops in New York City in 2006. Of the nearly 3,000 New York City Police Department officers regularly involved in pedestrian stops, we flag 15 officers who stopped a substantially greater fraction of black and Hispanic suspects than our statistical benchmark predicts. [ABSTRACT FROM AUTHOR]

Research has long identified racial differences in perceptions of criminal injustice. Given that race is confounded with neighbourhood context, it remains unclear the extent to which individual or neighbourhood attributes explain racial differences in these perceptions. This paper advances research on racial differences in perceptions of unjust police practices in the US by relying on a survey of 3000 residents in 53 Cincinnati neighbourhoods. A propensity score weighting approach is used to identify a model by which Whites and Blacks living in similar neighbourhood environments can be compared with each other. The results demonstrate that race remains a significant predictor of perceptions of unjust police practices, even after taking into account the ecological structuring of neighbourhoods and their perceived environmental context. These findings suggest that racial consciousness with regard to perceived injustices by the police is not purely a condition of personal or structural disadvantage. The implications of these findings for police reform efforts to mend minority relations in urban cities are discussed. [ABSTRACT FROM AUTHOR]

Advances in digitalized image optics has increased the importance of chromatic aberration. The axial and lateral chromatic aberrations of an optical lens depends on the choice of optical glass. Based on statistics from glass companies worldwide, more than 300 optical glasses have been developed for commercial purposes. However, the complexity of optical systems makes it extremely difficult to obtain the right solution to eliminate small chromatic aberration. Even the damped least-squares technique, which is a ray-tracing-based method, is limited owing to its inability to identify an enhanced optical system configuration. Alternatively, this study instead attempts to eliminate even negligible axial and lateral colour aberration by using algorithms involving the theories of geometric optics in triplet lens, binary and real encoding, multiple dynamic crossover and random gene mutation techniques. [ABSTRACT FROM AUTHOR]

Introduction . Both Channon, Baker, and Robertson (1993) and Hartlage, Alloy, Vazquez, and Dykman (1993) claim that working memory impairment in depressed patients is limited to Baddeley's (1996) central executive and does not affect either the phonological loop or the visuospatial scratchpad. Our key questions were: (1) is there an impairment of working memory in depression and which elements does it effect; (2) is another major clinical group also affected and in what ways, and finally, (3) how do these groups vary when compared with each other and with normals? Thus we sought to locate a depression‐specific effect and define its extent. Methods . We tested 35 depressed patients, using both 24 anxiety patients and 29 normal controls as comparisons. Several tasks were used so that we could differentiate between the three key aspects of working memory. Results . Contrary to Channon et al., we found that depression affects the allocation of attention and all elements of working memory. The depression group showed a distinct performance profile, with impairments occurring on measures of both the phonological loop and visuospatial sketch pad. On measures of central executive functioning, both depression and anxiety groups showed comparable levels of impairment when compared with the control group. Conclusions . We propose that the source of general disruption in both depressed and anxious patients may be a competition between attempts to direct attentional resources to the task in hand and away from the distractive and intrusive effects of automatic negative thoughts. [ABSTRACT FROM AUTHOR]

An immobility reflex may be induced in fish by a vigorous flow of water through the branchial chamber. The reflex was observed in 22 species representing bony and cartilaginous fishes from diverse habitats, and was invariably characterised by loss of caudal muscle tone and limp posture. The immobilised state may be maintained for many hours, and revival is instantaneous. The critical flow rate for induction increases with increasing body size in the snapper, Pagrus auratus, and heart rate falls below the resting rate. In addition, haematological parameters, and plasma lactate after 6?h were typical of resting fish. Although the mechanism is unclear, and the selective advantage for the fish unknown, pressure-sensitive receptors in the branchial chamber are likely to be involved. Application in live fish transport, and recovery from handling and exercise stressors is suggested. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of previously observed rotational transitions up to J = 17 of the sym and asym rotamers of monodeuterated acetaldehyde using a three-level Hamiltonian incorporating connections between rotational states of the v sym = 0, v asym = 0 + and v asym = 0 - torsional energy level manifolds. Rotational transitions observed to be significantly perturbed in earlier studies, where the spectrum was fitted using a single-level Hamiltonian for the v sym = 0 torsional state and a separate two-level Hamiltonian for the non-rigid asym states, are now fitted satisfactorily. It is confirmed that the perturbations detected in the earlier studies and tentatively attributed there to torsion-rotation interactions between the energetically distinct sym and asym manifolds do indeed arise as a consequence of such interactions. Rotational and quartic centrifugal distortion constants are given for each torsional state, together with torsion-rotation coupling constants primarily responsible for the perturbations noted in the earlier studies. Tunnelling between the energetically distinct sym and asym potential wells of the torsional potential energy function is also discussed. [ABSTRACT FROM AUTHOR]

Examines the effects of aricept acetylcholine esterase inhibitor in the treatment of patients with mild-to-moderate Alzheimer's disease in the U.S. Administration of dose tolerance and maintenance; Improvements in cognitive and neuronal functioning; Increase in the availability of acetylcholine within the synapses of neurons.

Police use of force has become an important public policy concern and topic of research during the past few years. A number of researchers have hypothesized that the structural context of police departments may influence officers' use of force. Despite these claims, little is known on a national level about how law enforcement agencies manage and influence their officers' use of force. We analyzed data from a national probability sample of 265 agencies to examine the impact of agency-related characteristics on aggregate rates of reported police use of force. We found that agencies which require supervisors and other personnel to fill out use-of-force forms report significantly lower rates of force than agencies that allow officers to fill out their own forms. In contrast, agencies that collect use-of-force data for a specific purpose report significantly higher rates of force. The rate of violent crime in the reporting jurisdiction has the strongest association with reported use-of-force rates. Implications of this research for theory and policy are discussed. [ABSTRACT FROM PUBLISHER]

Editorial. Focuses on the preclinical development of the 1,2-diaminocyclohexane platinum compound and antineoplastic agent called oxaliplatin. Mechanism of activity and toxicity; Reason for the sensitivity of colorectal cancer to oxaliplatin; Plans for the development of oxaliplatin in the management of patients with colorectal cancer.