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41.
We developed a stochastic model for quantitative risk assessment for the Schistosoma mansoni (SM) parasite, which causes an endemic disease of public concern. The model provides answers in a useful format for public health decisions, uses data and expert opinion, and can be applied to any landscape where the snail Biomphalaria glabrata is the main intermediate host (South and Central America, the Caribbean, and Africa). It incorporates several realistic and case‐specific features: stage‐structured parasite populations, periodic praziquantel (PZQ) drug treatment for humans, density dependence, extreme events (prolonged rainfall), site‐specific sanitation quality, environmental stochasticity, monthly rainfall variation, uncertainty in parameters, and spatial dynamics. We parameterize the model through a real‐world application in the district of Porto de Galinhas (PG), one of the main touristic destinations in Brazil, where previous studies identified four parasite populations within the metapopulation. The results provide a good approximation of the dynamics of the system and are in agreement with our field observations, i.e., the lack of basic infrastructure (sanitation level and health programs) makes PG a suitable habitat for the persistence and growth of a parasite metapopulation. We quantify the risk of SM metapopulation explosion and quasi‐extinction and the time to metapopulation explosion and quasi‐extinction. We evaluate the sensitivity of the results under varying scenarios of future periodic PZQ treatment (based on the Brazilian Ministry of Health's plan) and sanitation quality. We conclude that the plan might be useful to slow SM metapopulation growth but not to control it. Additional investments in better sanitation are necessary.  相似文献   
42.
Contagion of emotions is a widely accepted characteristic of transformational leaders. However, the impact they may have on the Emotional Intelligence of their subordinates is an open question. In this paper, we analyse whether Transformational Leadership (LTF) perceptions influence the Emotional Intelligence of their groups (GEI). This is a novel approach within the actual interest on emotional intelligence and its role in group results. The participants were 272 subordinates from 52 groups that belonged to different private and public organizations in Spain. They completed a questionnaire including the variables of interest. Our study helps to clarify the relations between TFL perceptions and GEI, showing that TFL and GEI relate at the group level and that TFL is one of the predictors of the perception of GEI in work settings. Thus, the development of emotionally competent transformational leaders will produce emotionally competent groups that might increase their performance, efficiency and other processes (i.e., engagement).  相似文献   
43.
44.
Focusing on the Spanish case, this article addresses two fundamental questions: why were many unionized workers sceptical about state intervention in labour issues throughout the nineteenth century, and why did this attitude begin to change from the 1860s onwards? Its main thesis is that workers’ attitudes derived ultimately from different historical notions of ‘society’ that shaped their perceptions and experiences of labour relations and their attitude toward the role of the state. Thus, a notion of society as an aggregation of individuals shaped unionized Spanish workers’ hostility toward state intervention since the creation of the first unions in the 1840s. From the 1860s onward, a new conception of collective relations, namely ‘the social’, began to transform some workers’ expectations of the role of the state in labour conflicts. The main factor that explains this change, it is argued, lies in the relationship between the workers’ imaginary, their actions, and their expectations about these actions.  相似文献   
45.
This study aimed to analyze the effects of caloric restriction on aged femoral articular cartilage of Wistar rats. Three groups of eight animals each were considered: young (YC) and old (OC) control groups fed with a normal diet and old caloric restriction group (OCR) composed of 18-month-old animals fed with a 31% less caloric diet from 6-months of age. Articular cartilage was studied through morphometry and immunohistochemistry. Body mass was 12% less in the OCR group than in the OC group. The articular cartilage from OC rats show thinner medial condyles, fewer chondrocytes, smaller chondrocytes nuclear volume and, in both condyles, a predominance of collagen type II and less collagen density compared to both YC and OCR groups (p?p?相似文献   
46.
R. Van de Ven  N. C. Weber 《Statistics》2013,47(3-4):345-352
Upper and lower bounds are obtained for the mean of the negative binomial distribution. These bounds are simple functions of a percentile determined by the shape parameter. The result is then used to obtain a robust estimate of the mean when the shape parameter is known.  相似文献   
47.
We consider the situation in which a buying organization deals with a discrete quantity discount schedule offered by a selling organization. Furthermore, the buying organization can negotiate with the selling organization about the lot size and purchase price, but does not know the underlying function that was used by the selling organization to determine the quantity discount schedule. In this paper, we provide an analytical and empirical basis for one general quantity discount function (QDF) that can be used to describe the underlying function of almost all different quantity discount types. We first develop such a QDF analytically. Among other things, this QDF enables buying organizations to calculate detailed prices for a large number of quantities. We subsequently show that the QDF fits very well with 66 discount schedules found in practice. We discuss that the QDF and related indicators can be a useful tool in supplier selection and negotiation processes. It can also be used for competitive analyses, multiple sourcing decisions, and allocating savings for purchasing groups. Additionally, the QDF can be included in research models incorporating quantity discounts. We conclude the paper with an outlook on further QDF research regarding the characterization of commodity markets from a demand elasticity point of view.  相似文献   
48.
We describe methods to detect influential observations in a sample of pre-shapes when the underlying distribution is assumed to be complex Bingham. One of these methods is based on Cook's distance, which is derived from the likelihood of the complex Bingham distribution. Other method is related to the tangent space, which is based on the local influence for the multivariate normal distribution. A method to detect outliers is also explained. The application of the methods is illustrated in both a real dataset and a simulated sample.  相似文献   
49.
Purpose The purpose of the paper is to present a theory of organisational change within the setting of a governmental bureaucracy. Design/methodology/approach Orthodox grounded theory is employed in the setting of a change programme in 12 Audit departments of the Dutch Ministries (public-sector). Findings The examined organisational change has specific characteristics. The Dutch ‘ministerial autonomy’ and the clearly recognizable role types of the key figures involved have a strong impact on the change programme and the realisation of its goals. Research limitations/implications Findings are derived on the basis of a substantive case study of the change programme of the Dutch Departmental Audit function. The research sheds new light on characteristics related to the occupational group of Chartered Accountants and characteristics of a governmental bureaucracy and it helps to understand change programmes within this bureaucracy. Practical implications The grounded theoretical model draws attention to the impact of key figures and circumstances on a change programme within the central government. Originality/value The paper builds on theories of organisational change but applies them in the typical context of the Dutch civil service where ministerial autonomy, on the one hand, and a move in the direction of more centrally organised activities (concern idea), on the other, require a difficult balancing act of all players in the change arena.  相似文献   
50.
Radon is a naturally occurring decay product of uranium known to be the main contributor to natural background radiation exposure. It has been established that the health risk related to radon exposure is lung cancer. In fact, radon is considered to be a major leading cause of lung cancer, second only to smoking. In this paper, we identified building typologies that affect the probability of detecting indoor radon concentration above reference values, using the data collected within two monitoring campaigns recently conducted in Northern Italy. This information is fundamental both in prevention, i.e. when the construction of a new building is planned and in mitigation, i.e. when a high concentration detected inside buildings has to be reduced. A spatial regression approach for binary data was adopted for this goal where some relevant covariates on the soil were retrieved by linking external spatial databases.  相似文献   
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