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41.
The aim of this paper is to obtain new sharp inequalities for a large family of topological indices, including the second variable Zagreb index \(M_2^{\alpha }\), and to characterize the set of extremal graphs with respect to them. Our main results provide lower bounds on this family of topological indices involving just the minimum and the maximum degree of the graph. These inequalities are new even for the Randi?, the second Zagreb and the modified Zagreb indices.  相似文献   
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The distribution of the aggregate claims in one year plays an important role in Actuarial Statistics for computing, for example, insurance premiums when both the number and size of the claims must be implemented into the model. When the number of claims follows a Poisson distribution the aggregated distribution is called the compound Poisson distribution. In this article we assume that the claim size follows an exponential distribution and later we make an extensive study of this model by assuming a bidimensional prior distribution for the parameters of the Poisson and exponential distribution with marginal gamma. This study carries us to obtain expressions for net premiums, marginal and posterior distributions in terms of some well-known special functions used in statistics. Later, a Bayesian robustness study of this model is made. Bayesian robustness on bidimensional models was deeply treated in the 1990s, producing numerous results, but few applications dealing with this problem can be found in the literature.  相似文献   
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Nongovernmental organizations (NGOs) are established not with the aim of making profits but rather to provide social values by implementing different projects and activities. Transmitting complete information about these projects to society is a key element of transparency, as they operate within an atmosphere of public trust. Although there is a large body of literature on transparency in NGOs from a global perspective, very little research has been conducted on transparency within the area of projects and activities. This study takes a deeper look at this line and contributes to the literature on transparency in NGOs by proposing an index to measure the information transparency of the projects implemented by these organizations. The index captures three dimensions of the information about the projects (technical, financial, and scope) and makes it possible to: analyze the level of transparency of the portfolio of projects, detect the specific aspects that could be improved in each organization, and carry out comparisons among organizations.  相似文献   
46.
ABSTRACT

Engagement of individuals with serious mental illnesses in community mental health services is a significant challenge. The Program of Assertive Community Treatment (PACT) is an individual-centered and self-contained mental health program that provides psychiatric treatment, rehabilitation, and support services to persons with serious mental illness who have a history of or likelihood of disengagement with services. Understanding what helps and hinders consumers’ involvement in PACT services may provide information on how to tailor engagement strategies to individuals based on their treatment needs and preferences. The current study builds on existing studies by exploring factors that help and hinder engagement in PACT services from the perspectives of individuals receiving treatment. We conducted open-ended, semi-structured interviews with 17 individuals receiving PACT services. Nine themes were identified through thematic analysis: Desirable qualities of PACT, Focusing on positive outcomes, PACT as a safety net, Recovery orientation, Practical barriers, Conflictual relationships, and Medication side-effects. We conclude that the development of a trusting, therapeutic relationship that is collaborative and person-centered and that is facilitated by both practical and emotional support is critical to engaging individuals in treatment and maximizing positive outcomes.  相似文献   
47.
Objective: Given the importance of developmental transitions on young adults' lives and the high rates of mental health issues among U.S. college students, first-year college students can be particularly vulnerable to stress and adversity. This pilot study evaluated the effectiveness and feasibility of mindfulness training aiming to promote first-year college students' health and wellbeing. Participants: 109 freshmen were recruited from residential halls (50% Caucasian, 66% female). Data collection was completed in November 2014. Methods: A randomized control trial was conducted utilizing the Learning to BREATHE (L2B) program, a universal mindfulness program adapted to match the developmental tasks of college transition. Results: Participation in the pilot intervention was associated with significant increase in students' life satisfaction, and significant decrease in depression and anxiety. Marginally significant decrease was found for sleep issues and alcohol consequences. Conclusions: Mindfulness-based programs may be an effective strategy to enhance a healthy transition into college.  相似文献   
48.
Understanding the motives that underlie Spaniards’ retirement saving decisions is important because many, if not most, future retirees will need to rely on personal savings to maintain a decent standard of living. The governor of the Bank of Spain has stated recently that the current public pension system will not guarantee an adequate pension to the citizens, advising to save now for retirement. In this debate on public pensions, and the complementary role that private pensions might play in Spain, this article has shed light on the decision of Spanish households to engage in individual pension plans and it has identified which factors determine the total amount saved in such retirement plans. Using micro data from the Bank of Spain (Survey of Household Finances 2011), the analysis has revealed that the expectations of lower future income, along with preferences for the financial risk and education, exert an important influence on the likelihood of enrolling in a private pension plan. University education minimizes the myopic behavior of households in the sense of making them more forward-looking and cautious in the face of their future well-being. Additionally using Heckman’s methodology to correct for the problem of selection bias, our results have revealed that liquidity constraints affect negatively the total amount of money saved for retirement.  相似文献   
49.
Does urbanization affect key life-history traits in native organisms? Some studies show that urban areas reduce diversity in certain taxa, but there is little insight into how these environments affect physiological and ecological traits. Urban areas have distinct physical structure and ecological processes compared to original habitats. The environmental changes associated with urban areas can influence the costs and benefits of different traits and behaviors of local organisms. Some of these effects have been explored in groups such as birds, but we might expect stronger effects in animals with reduced mobility, such as amphibians. Importantly, the effects of urban habitats on amphibians have not been explored, in spite that these are the most threatened vertebrate group in the world. Here, we compared three main traits related to the fitness of amphibians in urban and natural habitats: body size, body condition and immune response. To test the generality of our results, we assessed adult males of four amphibian species. We found that the body size was larger in urban environment populations in three of four studied species, while the body condition was better in the urban populations of two aquatic newt species. Finally, we found no effect of urbanization on the immune response of individuals of any species. In conclusion, we show that different species of amphibians may be affected differently by anthropogenic habitat alteration depending on their specific ecology.  相似文献   
50.
Over the last decade, we have witnessed the emergence of an academic debate surrounding the relationship between youth and the ‘new media’, with a particular emphasis on the social uses of different digital technologies within the sphere of youth activity. A specific area of research has been dedicated to studying the use of digital media in the context of the so-called youth subcultures. With this article we expect to contribute to this ongoing debate, by examining the problem through an analysis of two interconnected case studies: protest rap and illegal graffiti. Both cases may be defined as subcultures, insofar as they are characterized as alternative, subterranean, and to a certain extent, subversive movements. The empirical ground for this discussion is based on several investigations, with a qualitative basis, carried out by the authors in the course of over a decade in Portugal. This extended time frame allowed ample access to a diversified and matured analytical material and enabled a better perspective of the developments and the mutations involving the appropriation of the digital media. Our researches have shown that digital media and technologies have been gradually integrated in these urban youth subcultures, accomplishing several strategic roles.  相似文献   
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