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91.
We present a new biclustering algorithm to simultaneously discover tissue classes and identify a set of genes that well-characterize these classes from DNA microarray data sets. We employ a combinatorial optimization approach where the object is to simultaneously identify an interesting set of genes and a partition of the array samples that optimizes a certain score based on a novel color island statistic. While this optimization problem is NP-complete in general, we are effectively able to solve problems of interest to optimality using a branch-and-bound algorithm. We have tested the algorithm on a 30 sample Cutaneous T-cell Lymphoma data set; it was able to almost perfectly discriminate short-term survivors from long-term survivors and normal controls. Another useful feature of our method is that can easily handle missing expression data.  相似文献   
92.
An increasing number of aging community providers and consumers support consumer-direction (CD) in long-term care services. In regard to devolution, consumer-direction goes beyond the usual approach of shifting responsibilities from the federal government to state governments to bring programs "closer to the people." Consumer-direction goes even further by placing resources directly in the hands of consumers. Yet, many questions remain unanswered regarding how to implement CD personal assistance services in general, and especially for older persons. This article describes the importance of examining views from multiple key stakeholders involved in implementing CD programs. We report on three background studies that have informed the Cash and Counseling Demonstration and Evaluation (CCDE) design and implementation-policy expert interviews as well as surveys and focus groups with consumers and representatives. As a fourth data source, we drew upon experiences in designing the CCDE and initial results from the first year of implementation. Each of the three studies on its own provided essential information for planning the CCDE. However, when we examined the studies together, and added CCDE design and implementation experiences, views expressed by the different stakeholders formed a type of multi-perspective "dialogue" that expanded our knowledge about implementing CD services. We hope this increased knowledge will help expand the availability of such services for consumers of any age who want to direct their own care.  相似文献   
93.
Urban Ecosystems - Urbanisation affects fauna in many ways; with some species persisting and going on to dominate urban habitats, while other species decline over time due to habitat disturbance...  相似文献   
94.
Technology has globalized businesses. International business is difficult due to differences in languages and cultures. In terms of technology, in some countries, it is difficult to get data; while in others, data is input in different ways. This paper examines how international differences affect website design, implementation and usage. We analyze websites of airlines and hotels. While some websites take into consideration language and culture differences, we find significant room for improvement in both industries. We found support for localization strategy in marketing, communication and transactions. Theoretical and practical implications, including language translators, currency converters and pull-down fields, are discussed.  相似文献   
95.
Federal and other regulatory agencies often use or claim to use a weight of evidence (WoE) approach in chemical evaluation. Their approaches to the use of WoE, however, differ significantly, rely heavily on subjective professional judgment, and merit improvement. We review uses of WoE approaches in key articles in the peer‐reviewed scientific literature, and find significant variations. We find that a hypothesis‐based WoE approach, developed by Lorenz Rhomberg et al., can provide a stronger scientific basis for chemical assessment while improving transparency and preserving the appropriate scope of professional judgment. Their approach, while still evolving, relies on the explicit specification of the hypothesized basis for using the information at hand to infer the ability of an agent to cause human health impacts or, more broadly, affect other endpoints of concern. We describe and endorse such a hypothesis‐based WoE approach to chemical evaluation.  相似文献   
96.
Emerging “prevention‐based” approaches to chemical regulation seek to minimize the use of toxic chemicals by mandating or directly incentivizing the adoption of viable safer alternative chemicals or processes. California and Maine are beginning to implement such programs, requiring manufacturers of consumer products containing certain chemicals of concern to identify and evaluate potential safer alternatives. In the European Union, the REACH program imposes similar obligations on manufacturers of certain substances of very high concern. Effective prevention‐based regulation requires regulatory alternatives analysis (RAA), a methodology for comparing and evaluating the regulated chemical or process and its alternatives across a range of relevant criteria. RAA has both public and private dimensions. To a significant degree, alternatives analysis is an aspect of product design; that is, the process by which private industry designs the goods it sells. Accordingly, an RAA method should reflect the attributes of well‐crafted product design tools used by businesses. But RAA adds health and environmental objectives to the mix of concerns taken into account by the product designer. Moreover, as part of a prevention‐based regulatory regime, it implicates important public values such as legitimacy, equity, public engagement, and accountability. Thus, an RAA should reflect both private standards and public values, and be evaluated against them. This article adopts that perspective, identifying an integrated set of design principles for RAA, and illustrating the application of those principles.  相似文献   
97.

Multiple regression techniques were used to explore the nature of the relationships between age, tenure and absence in 2417 British local government workers drawn from three work groups. The data were collected from organizational records and included measures of both non-certified absence and medically certified absence. Linear and curvilinear associations among age, tenure and absence were examined. The possible moderating or mediating role of tenure in the relationship between age and absence was subsequently analysed. The data revealed linear relationships between age and absence that were negative for non-certified absence and positive for certified absence. In contrast, curvilinear relationships were found between tenure and absence that were U-shaped for noncertified absence and inverse U-shaped for certified absence. Tenure was found to moderate but not to mediate the relationship between age and absence. The implications of the results are discussed in the context of the changing age and career paths of the workforce, and of methodological issues in absence research.  相似文献   
98.
Abstract

The relationship between accidents and the time of day is not entirely clear. Although there is considerable evidence that performance is poorest in the early morning hours compared to at all other times, the degree to which this is translated into accidents is not understood. In this study work-related fatal accidents were analysed to determine whether the causes of these accidents vary with time. The analysis used a classification and coding system devised to describe the wider circumstances of the causes of fatalities. In terms of absolute numbers, fatalities were most common in the late morning or early afternoon. When these results were expressed in terms of the estimated number of workers at work, the proportion of fatal accidents occurring at night was more than double that occurring during the day. Behavioural factors were the most common cause of fatalities at all times, but most common in the early hours of the morning. Further analysis of the nature of the behavioural involvement showed that errors in automatic processing (skill-based errors) were the most common types of error and did not vary much with time of day. Rule-based errors were most common during the day whereas knowledge-based errors occurred mainly in the afternoon and night shifts. These results cast some doubt on the assumption that there is a direct relationship between the previously observed variations in performance across time and the ultimate safety outcome.  相似文献   
99.
This article focuses on the pattern and impact of change leadership in complex, pluralistic, public sector settings, and specifically in English healthcare. The argument draws on evidence from ten comparative cases, exploring links between leadership patterns and organizational outcomes. Our analysis builds three themes. First, a pattern of widely distributed change leadership is linked to delivering improvements in service outcomes. Second, professional/managerial hybrids are shown to perform crucial lateral facilitation activities, adapting and extending their roles to suit their organizational context. Third, a foundation of good pre-existing relationships underpins the capacity of distributed leadership to implement service improvements. Conversely, poor relationships and conflicts erode the concerted capacity of distributed change leadership. The key contribution of this article thus concerns the establishment of links between situated patterns of distributed leadership, and service improvement outcomes, based on the cumulative effects of actors – managers and clinical hybrids – at different organizational levels.  相似文献   
100.
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