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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   
74.
The study aimed to identify different patterns of gambling activities (PGAs) and to investigate how PGAs differed in gambling problems, substance use outcomes, personality traits and coping strategies. A representative sample of 4989 young Swiss males completed a questionnaire assessing seven distinct gambling activities, gambling problems, substance use outcomes, personality traits and coping strategies. PGAs were identified using latent class analysis (LCA). Differences between PGAs in gambling and substance use outcomes, personality traits and coping strategies were tested. LCA identified six different PGAs. With regard to gambling and substance use outcomes, the three most problematic PGAs were extensive gamblers, followed by private gamblers, and electronic lottery and casino gamblers, respectively. By contrast, the three least detrimental PGAs were rare or non-gamblers, lottery only gamblers and casino gamblers. With regard to personality traits, compared with rare or non-gamblers, private and casino gamblers reported higher levels of sensation seeking. Electronic lottery and casino gamblers, private gamblers and extensive gamblers had higher levels of aggression-hostility. Extensive and casino gamblers reported higher levels of sociability, whereas casino gamblers reported lower levels of anxiety–neuroticism. Extensive gamblers used more maladaptive and less adaptive coping strategies than other groups. Results suggest that gambling is not a homogeneous activity since different types of gamblers exist according to the PGA they are engaged in. Extensive gamblers, electronic and casino gamblers and private gamblers may have the most problematic PGAs. Personality traits and coping skills may predispose individuals to PGAs associated with more or less negative outcomes.  相似文献   
75.
The existing literature on the determinants of income redistribution has identified a ‘paradox’. Namely, that countries with a high degree of market income inequality redistribute little, which is in disagreement with the median voter theorem. In a first step, this paper outlines several mechanisms that explain why government corruption might be partially responsible for this ‘paradox’. In a second step, different corruption perception indices and an instrumental variable approach are used to provide empirical evidence that indicates a significant negative impact of corruption on redistribution levels for a sample of 148 developing and developed countries. This finding suggests that, next to political and need factors, government corruption explains to some extent the ‘paradox of redistribution’. This is especially true for many developing countries, given that they typically have relatively high degrees of corruption and low levels of redistribution.  相似文献   
76.
Organisations in the health and social services sector expend a considerable amount of energy promoting the implementation of better practices and research data use in their establishments. In the field of social work, several studies suggest that social work practitioners do not make great use of scientific knowledge and tend to favour knowledge acquired from their colleagues or through their own occupational experience. However, interactions between types of knowledge are rarely analyzed in explanations proposed by the scientific literature. Based on research conducted with social work practitioners in child welfare, this article discusses the different ways that they acquire knowledge.  相似文献   
77.
Several colorectal cancer (CRC) screening models have been developed describing the progression of adenomas to CRC. Currently, there is increasing evidence that serrated lesions can also develop into CRC. It is not clear whether screening tests have the same test characteristics for serrated lesions as for adenomas, but lower sensitivities have been suggested. Models that ignore this type of colorectal lesions may provide overly optimistic predictions of the screen‐induced reduction in CRC incidence. To address this issue, we have developed the Adenoma and Serrated pathway to Colorectal CAncer (ASCCA) model that includes the adenoma‐carcinoma pathway and the serrated pathway to CRC as well as characteristics of colorectal lesions. The model structure and the calibration procedure are described in detail. Calibration resulted in 19 parameter sets for the adenoma‐carcinoma pathway and 13 for the serrated pathway that match the age‐ and sex‐specific adenoma and serrated lesion prevalence in the COlonoscopy versus COlonography Screening (COCOS) trial, Dutch CRC incidence and mortality rates, and a number of other intermediate outcomes concerning characteristics of colorectal lesions. As an example, we simulated outcomes for a biennial fecal immunochemical test screening program and a hypothetical one‐time colonoscopy screening program. Inclusion of the serrated pathway influenced the predicted effectiveness of screening when serrated lesions are associated with lower screening test sensitivity or when they are not removed. To our knowledge, this is the first model that explicitly includes the serrated pathway and characteristics of colorectal lesions. It is suitable for the evaluation of the (cost)effectiveness of potential screening strategies for CRC.  相似文献   
78.
This article examines media consumption in highly diverse districts in Spain as representative of recent changes in this field due to new immigration to countries in Southern Europe in times of crisis. Drawing on findings from two surveys, we observed a decrease in access to media specifically aimed at audiences of minority cultures between 2010 and 2012. It is suggested that this decline is not due to a modification in media consumption habits by minority groups, but rather the economic crisis of 2008. Furthermore, we study the consumption of minority media by natives: we observe that youth and more educated individuals consume other cultures’ minority media to a greater extent, particularly the press, radio, and Internet news sources. We suggest that elements are present that public administrations could utilize to further develop a multi‐ethnic public sphere. Finally, we explore the emergence of a new transnational dimension to the multi‐ethnic public sphere.  相似文献   
79.
The objective of this work was to summarise and evaluate the evidence showing that physical activity is a protector factor as regards falls in older people. Relevant studies were identified through a systematic search in the MEDLINE and Cochrane Library, under the keywords of accidental fall/numerical data and risk factors, and with the bibliographies of retrieved papers. The combined odds ratio (OR) [95% confidence interval] for physical activity was 0.75 [0.64, 0.88] with moderate heterogeneity (I 2?=?33%). For fall injury, it was 0.59 [0.47, 0.74] and, for falls in general, it rose to 0.94 [0.76, 1.17] with nil heterogeneity. The combined OR for sedentary factors was 1.14 [1.10, 1.82] with moderate heterogeneity (I 2?=?36%). Regular physical activity in daily life yields significant reduction in falls in older people, especially falls with injuries.  相似文献   
80.
Health and safety issues in a vocational training center were explored in this study. Several sources and methods were used: group interviews with students in traditionally female [F] and male [M] trades, i.e. hairdressing (7 F) and automated systems electromechanics (8 M, 1 F); self-administered questionnaires on injuries sustained at the school; observations of activities in these programs; and analysis of ministerial documents. Findings indicate that the partially divergent ways that OHS is addressed in these programs cannot be explained only by the specific characteristics of the two trades. Some aspects put female students in hairdressing at a disadvantage: status accorded to OHS in the study programs, learning activities, and conditions for learning and managing prevention and injuries. The discussion focuses on a gender-differentiated analysis, the importance of improving the way OHS is addressed in the programs, in particular, those primarily involving female students, and the need to pursue research. In addition, the results from individual interviews with women (5 F) training for non-traditional trades lead to discussion on the interrelated effects of sex-based gender and professional gender.  相似文献   
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