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151.
This article describes the development of a weighted composite dose – response model for human salmonellosis. Data from previously reported human challenge studies were categorized into two different groups representing low and moderately virulent/pathogenic Salmonella strains based on a disease end point. Because epidemiological data indicate that some Salmonella strains are particularly pathogenic, and in the absence of human feeding study data for such strains, Shigella dysenteriae was used as a proxy for highly virulent strains. Three single-hit dose – response models were applied to the human feeding study data and evaluated for best fit using maximum likelihood estimation: (1) the exponential (E-1pop), (2) the two-subpopulation exponential (E-2pop), and (3) the Beta-Poisson (BP). Based on the goodness-of-fit test, the E-1pop and BP were the best-fit models for low and moderately virulent/pathogenic Salmonella strains, and the E-2pop and BP models were better for highly virulent/pathogenic strains. Epistemic analysis was conducted by determining the degree of confidence associated with the selected models, which was found to be 50%/50% (E-1pop/BP) for low and moderately pathogenic Salmonella strains, and 9.8%/90.2% (E-2pop/BP) for highly virulent strains. The degree of confidence for each component model and variations in the proportion of strains within each virulence/pathogenicity category were incorporated into the overall composite model. This study describes the influence of variation in strain virulence and host susceptibility on the shape of the population dose – response relationship.  相似文献   
152.
Violence against psychiatric staff seems to be on the increase. Such abuse can lead to mental health consequences for the staff and a reluctance to be closely involved with patients. Few Swedish investigations have examined violence against mental nurses and psychiatrists, or undertaken comparative studies between them. In this study we examined the extent, nature and determinants (i.e. risk factors) of violence against psychiatric nurses (n = 731) and psychiatrists (n = 320) working in the eight health care districts of Stockholm. These caregivers were assessed cross-sectionally by means of a questionnaire covering various areas (e.g. violence and work environment). The majority of the participants (85%) reported having been exposed to violence during their careers, with 57% being victimized in the past 12 months. Physical violence was common, and factors such as negative attitudes to work and diminished sense of autonomy were associated with an increased vulnerability to violence. Nurses and psychiatrists did not differ in violence variables. In spite of the weaknesses of the design (cross-sectional self-selecting sample), this study corroborates previous findings and identifies personal factors associated with violence that have received little attention in the literature (e.g. lack of respect for the organization of care).  相似文献   
153.
The theory of the firm seeks to explain the existence and boundaries of the firm in relation to the market. Since the pioneering work of Coase (The nature of the firm. Economica , 4 , 386–405, 1937), economics has developed a whole family of theories that focus on the ability of firms to economize on certain costs of using markets. More recently, researchers in strategic management have published several theories of the firm that have tended to emphasize the benefits of incorporation rather than the costs of using the market. Although researchers in the strategy profession have tentatively labeled their work as 'moving towards' a strategic theory of the firm, economists have been very critical of existing approaches. This paper seeks to begin 'arriving' at a strategic theory of the firm by addressing these criticisms and offering an integration of the strategic and economic perspectives within an institutional framework. The paper concludes with future directions for research in the theory of the firm.  相似文献   
154.
Public–Private Partnerships (PPPs) have become a critical vehicle for delivering infrastructure worldwide. Yet, the use of such a procurement strategy has received considerable criticism, as they have been prone to experiencing time/cost overruns and during their operation poorly managed. A key issue contributing to the poor performance of PPPs is the paucity of an effective and comprehensive performance measurement system. There has been a tendency for the performance of PPPs to be measured based on their ex-post criteria of time, cost and quality. Such criteria do not accommodate the complexities and lifecycle of an asset. In addressing this problem, the methodology of sequential triangulation is used to develop and examine the effectiveness of a ‘Process Management Life Cycle Performance Measurement System’. The research provides public authorities and private-sector entities embarking on PPPs with a robust mechanism to effectively measure, control and manage their projects’ life cycle performances, ensuring the assets are ‘future proofed’.  相似文献   
155.
156.
Zusammenfassung  Dieser Beitrag befasst sich mit dem Ausstieg von Gesellschaftern aus Familienunternehmen als bedeutendes Corporate Governance-Problem. Im Mittelpunkt steht die Untersuchung der Wirkung von Ausstiegsmotiven, Rahmenbedingungen sowie Ausstiegsbarrieren auf die Belastung von Unternehmen und Familie durch den Gesellschafterausstieg. Eine explorative empirische Untersuchung von 55 gro?en deutschen Familienunternehmen liefert Ans?tze für eine Organisationstheorie des Familienunternehmens und für praktische Empfehlungen bei der Gestaltung von Satzung und Ausstiegsverhandlung.
Summary  This article deals with the exit of shareholders in family owned businesses as an important corporate governance problem. We mainly analyse the effect of exit motivations, exit conditions, and barriers to exit on the exit’s burden for the company and the family. An explorative empirical study of 55 large German family owned businesses comes up with ideas for an organization theory of family owned businesses as well as some practical recommendations for statutes and exit negotiations.
  相似文献   
157.
In this paper, we investigate a one‐warehouse multiple‐retailer system, where the inventory control decisions are coordinated using a near optimal induced backorder cost, β*. All installations use continuous review installation‐stock (R, Q) policies. The analysis builds on an approximation model where the stochastic warehouse delays are replaced by their correct averages. The contributions include insights as to how β* is influenced by system parameters, and the determination of simple closed form β* estimates. The latter offering a practical means to achieve coordinated control of large size systems.  相似文献   
158.
Although the issue of risk target (e.g., self, others, children) is widely acknowledged in risk perception research, its importance appears underappreciated. To date, most research has been satisfied with demonstrating comparative optimism, i.e., lower perceived risk for the self than others, and exploring its moderators, such as perceived controllability and personal exposure. Much less research has investigated how the issue of target may affect benefit perceptions or key outcomes such as stated preferences for hazard regulation. The current research investigated these issues using data from a public survey of attitudes toward mobile phone technology (N= 1,320). First, results demonstrated comparative optimism for this hazard, and also found moderating effects of both controllability and personal exposure. Second, there was evidence of comparative utility, i.e., users believed that the benefits from mobile phone technology are greater for the self than others. Third, and most important for policy, preferences for handset regulation were best predicted by perceptions of the risks to others but perceived benefits for the self. Results suggest a closer awareness of target can improve prediction of stated preferences for hazard regulation and that it would be profitable for future research to pay more attention to the issue of target for both risk and benefit perceptions.  相似文献   
159.
There are many moves you can make to maintain staff morale, provide staff with challenges and keep them content.  相似文献   
160.
The debate continues over whether prescribed quantities or unit pricing offers the best method to enable consumers to make value-for-money comparisons. In theory, the 'informed' consumer should benefit from being given unit-price information to identify optimum purchases; in practice, however, it would appear that many consumers do not use the data. Although unit pricing can reduce the level of confusion caused by large product ranges and large numbers of unique size–price combinations, results of a survey of over 1000 people showed that: 31% of the sample did not understand how unit pricing was meant to help them compare products; 35% could not be bothered to look at unit prices and 28% stated that unit pricing was too difficult to use. Those least likely to look at unit prices are women, the least educated and consumers aged 18–34. The research investigated why consumers do not use unit-price information and found: some consumers do not possess the cognitive ability to process the information and feel unit pricing is too complicated to use; some products are not comparable, which makes unit prices misleading; many shops do not provide unit-price information; unit-price information was felt unnecessary when evaluating products with few or no alternative sizes or brands; unit-price comparisons take too much time; consumers use simpler strategies for getting value for money, e.g. volume discount heuristic, own brands, special offers, x% free, reward points, etc. The paper explores policy and retailer implications for unit pricing and examines recommendations for government.  相似文献   
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