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81.
Public-Private Partnership (PPP) is a new model of public management which consists of the contractual relationship between public and private entities. In particular, PPPs enable risk share between public and private sectors making the asymmetric information problem in a contractual arrangement more evident. The aim of this paper was to study a moral hazard problem applied to PPP contracts. To achieve this objective, a PPP computational contractual model including the moral hazard with lotteries was developed to assess how contractual changes could affect the optimum behavior of arrangement members. Simulations indicate that projects with higher economic value should attract more qualified firms, which may be why the companies expend more effort. To deal with possible contractual contingencies and try to minimize the moral hazard problem, the government could draw up more flexible contracts in order to include possible necessary changes and punish unwanted or improper consortium behavior.  相似文献   
82.
Abstract

Objective: The purpose of this review is to examine the evidence on the effects of bioactive constituents of the Mediterranean diet (MeDi) on prostate cancer (PCa) risk.

Methods: The search for articles came from extensive research in the following databases: PubMed, Scopus, and Web of Science. We used the search terms “Mediterranean diet,” “lycopene,” “vitamin E,” “vitamin C,” “Selenium,” “resveratrol,” “prostate cancer,” and combinations, such as “lycopene and prostate cancer” or “resveratrol and prostate cancer.”

Results: Numerous studies investigating the effect of various dietary nutrients on PCa have suggested that selenium is probably the most promising. Several studies reported reduced PCa risk associated with vitamin C and E intake, while other studies reported no association. Lycopene inhibits cell proliferation and inducts apoptosis, thus protecting against cancer. Also, it has been found in various in vivo and in vitro studies that resveratrol, inhibits PCa development.

Conclusions: The high content of bioactive phytochemicals in the MeDi is of particular interest in the prevention of PCa. Further large-scale studies are required to clarify the effect of MeDi bioactive compounds on prostate health, in order to establish the role of this diet in the prevention of PCa.  相似文献   
83.
ABSTRACT

Useful knowledge acquisition from known and systematized information (data) is a big challenge for researchers, users and finally, decision makers. In this sense, knowledge discovery from data (KDD) process represents a valuable tool for information analysis. Moreover, this work presents an approach through KDD in time series pattern identification for anchovy and sardine fisheries and environmental data, in northern Chile. Time series, multivariate analysis and data mining techniques, along with technical literature review for results validation. The KDD approach and the data mining techniques implemented achieved an integration between these variables, identifying relevant patterns associated with fisheries abundance fluctuations and strong association with environmental changes such as El Niño and long-term cold–warm regimes between them, establishing anchovy and sardine pre-dominant time-periods, associated with environmental conditions are identified. The latter establishes groundwork for studying underlying functional relationships that could reduce gaps in the national fisheries management policies for those fisheries.  相似文献   
84.
ABSTRACT

This article draws on a qualitative research project concerning the relationship between trans people’s mental health and wellbeing, pressures, social policy, and heteronormative gender norms in Spain. Drawing on interviews carried out with trans people from all regions and generations, we use an ecological framework to illustrate how a socially entrenched heteronormativity pressures trans people to comply with gender norms that impact negatively their mental health and wellbeing. The article argues that the legal changes in Spain are not enough in themselves to bring about social change, but, rather, Spanish social policy makers also need to challenge gender categorization and work toward transforming public discourses on gender issues if trans people are to gain full social recognition and equal social rights.  相似文献   
85.
The polyhazard model with dependent causes, first introduced to fit lifetime data, generalized the traditional polyhazard model by allowing the latent causes of failure to be dependent by using copula functions. When modeling lifetime data, marginal distributions are supported on the positive reals. Dropping this restriction, the method generates a rich family of univariate distributions with asymmetries and multiple modes. We show that this new family of distributions is able to approximate other distributions proposed in the literature, such as the generalized beta-generated distributions. These distributions are fitted to three real data sets.  相似文献   
86.
This study analyses the expected changes in survivors’ pensions resulting from the permanent rules of the 2019 pension reform in Brazil. Actuarial annuities are used for representative worker profiles. The dispersion in the replacement rate values decreases, except for the highest income level. The rates needed to finance survivors’ pensions decrease relatively more than do the rates for old-age pensions. The internal rates of return significantly decrease. There is a heterogeneous change in the distributive aspects of the pension system. The reform shall affect the adequacy and intragenerational equity of old-age and survivors’ pensions.  相似文献   
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