313 research outputs found

    The power of choice in network growth

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    The "power of choice" has been shown to radically alter the behavior of a number of randomized algorithms. Here we explore the effects of choice on models of tree and network growth. In our models each new node has k randomly chosen contacts, where k > 1 is a constant. It then attaches to whichever one of these contacts is most desirable in some sense, such as its distance from the root or its degree. Even when the new node has just two choices, i.e., when k=2, the resulting network can be very different from a random graph or tree. For instance, if the new node attaches to the contact which is closest to the root of the tree, the distribution of depths changes from Poisson to a traveling wave solution. If the new node attaches to the contact with the smallest degree, the degree distribution is closer to uniform than in a random graph, so that with high probability there are no nodes in the network with degree greater than O(log log N). Finally, if the new node attaches to the contact with the largest degree, we find that the degree distribution is a power law with exponent -1 up to degrees roughly equal to k, with an exponential cutoff beyond that; thus, in this case, we need k >> 1 to see a power law over a wide range of degrees.Comment: 9 pages, 4 figure

    An initial set of exploratory case studies regarding the role of the biomedical physics-engineering educator as practiced in health science faculties in Europe

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    The role of biomedical physics-engineering (BMPE) educator in faculties of health science has historically not been well defined with the result that its status within such faculties has sometimes been questioned. It is therefore important that the role be thoroughly researched and good practices identified so that the presence of the role within such faculties be properly justified. This paper reports briefly the results of an initial set of exploratory case studies regarding the role as practiced in universities from three European states having diverse health science faculty and higher educational structures, namely the Czech Republic, the Republic of Ireland and the Netherlands. Data was collected from university websites, published documents, curricular materials and textbooks. This data was supplemented when necessary with semi-structured interviews and direct observation during on-site visits.peer-reviewe

    Loneliness across cultures with different levels of social embeddedness:A qualitative study

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    Valid theorizing and quantitative comparisons of loneliness across cultures require cross‐culturally similar meanings of loneliness. However, we know little about whether this is the case: Influential conceptualizations of loneliness mostly come from North America or Europe, where individuals tend to have relatively few stable social relationships and social interactions (i.e., less socially embedded cultures). We thus compare selected conceptualizations of loneliness from the literature to loneliness experiences that are reported in 42 semi‐structured interviews from countries with different levels of social embeddedness (Austria, Bulgaria, Israel, Egypt, India). Encouragingly, our thematic analysis does not suggest fundamental qualitative differences in loneliness definitions, perceived causes, or remedies. Nevertheless, we noticed and discuss aspects that may not be sufficiently considered in previous literature

    Longitudinal bidirectional associations between internalizing mental disorders and cardiometabolic disorders in the general adult population

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    Purpose This prospective population-based study investigated whether having any internalizing mental disorder (INT) was associated with the presence and onset of any cardiometabolic disorder (CM) at 3-year follow-up; and vice versa. Furthermore, we examined whether observed associations differed when using longer time intervals of respectively 6 and 9 years. Methods Data were used from the four waves (baseline and 3-, 6- and 9-year follow-up) of the Netherlands Mental Health Survey and Incidence Study-2, a prospective study of a representative cohort of adults. At each wave, the presence and first onset of INT (i.e. any mood or anxiety disorder) were assessed with the Composite International Diagnostic Interview 3.0; the presence and onset of CM (i.e. hypertension, diabetes, heart disease, and stroke) were based on self-report. Multilevel logistic autoregressive models were controlled for previous-wave INT and CM, respectively, and sociodemographic, clinical, and lifestyle covariates. Results Having any INT predicted both the presence (OR 1.28, p = 0.029) and the onset (OR 1.46, p = 0.003) of any CM at the next wave (3-year intervals). Having any CM was not significantly related to the presence of any INT at 3-year follow-up, while its association with the first onset of any INT reached borderline significance (OR 1.64, p = 0.06), but only when examining 6-year intervals. Conclusions Our findings indicate that INTs increase the risk of both the presence and the onset of CMs in the short term, while CMs may increase the likelihood of the first onset of INTs in the longer term. Further research is needed to better understand the mechanisms underlying the observed associations

    National-level wealth inequality and socioeconomic inequality in adolescent mental well-being: a time series analysis of 17 countries

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    Purpose: Although previous research has established a positive association between national income inequality and socioeconomic inequalities in adolescent health, very little is known about the extent to which national-level wealth inequalities (i.e., accumulated financial resources) are associated with these inequalities in health. Therefore, this study examined the association between national wealth inequality and income inequality and socioeconomic inequality in adolescents' mental well-being at the aggregated level. Methods: Data were from 17 countries participating in three consecutive waves (2010, 2014, and 2018) of the cross-sectional Health Behaviour in School-aged Children study. We aggregated data on adolescents' life satisfaction, psychological and somatic symptoms, and socioeconomic status (SES) to produce a country-level slope index of inequality and combined it with country-level data on income inequality and wealth inequality (n = 244,771). Time series analyses were performed on a pooled sample of 48 country-year groups. Results: Higher levels of national wealth inequality were associated with fewer average psychological and somatic symptoms, while higher levels of national income inequality were associated with more psychological and somatic symptoms. No associations between either national wealth inequality or income inequality and life satisfaction were found. Smaller differences in somatic symptoms between higher and lower SES groups were found in countries with higher levels of national wealth inequality. In contrast, larger differences in psychological symptoms and life satisfaction (but not somatic symptoms) between higher and lower SES groups were found in countries with higher levels of national income inequality. Conclusions: Although both national wealth and income inequality are associated with socioeconomic inequalities in adolescent mental well-being at the aggregated level, associations are in opposite directions. Social policies aimed at a redistribution of income resources at the national level could decrease socioeconomic inequalities in adolescent mental well-being while further research is warranted to gain a better understanding of the role of national wealth inequality in socioeconomic inequalities in adolescent health. (C) 2020 Published by Elsevier Inc. on behalf of Society for Adolescent Health and Medicine

    Country-Level Meritocratic Beliefs Moderate the Social Gradient in Adolescent Mental Health: A Multilevel Study in 30 European Countries

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    Purpose: Adolescents with higher socioeconomic status (SES) report better mental health. The strength of the association—the “social gradient in adolescent mental health”—varies across countries, with stronger associations in countries with greater income inequality. Country-level meritocratic beliefs (beliefs that people get what they deserve) may also strengthen the social gradient in adolescent mental health; higher SES may be more strongly linked to adolescent's perceptions of capability and respectful treatment. Methods: Using data from 11–15 year olds across 30 European countries participating in the 2013/2014 Health Behaviour in School-aged Children study (n = 131,101), multilevel regression models with cross-level interactions examined whether country-level meritocratic beliefs moderated the association between two individual-level indicators of SES, family affluence and perceived family wealth, and three indicators of adolescent mental health (life satisfaction, psychosomatic complaints, and aggressive behavior). Results: For family affluence, in some countries, there was a social gradient in adolescent mental health, but in others the social gradient was absent or reversed. For perceived family wealth, there was a social gradient in adolescent life satisfaction and psychosomatic complaints in all countries. Country-level meritocratic beliefs moderated associations between SES and both life satisfaction and psychosomatic complaints: in countries with stronger meritocratic beliefs associations with family affluence strengthened, while associations with perceived family wealth weakened. Conclusions: Country-level meritocratic beliefs moderate the associations between SES and adolescent mental health, with contrasting results for two different SES measures. Further understanding of the mechanisms connecting meritocratic beliefs, SES, and adolescent mental health is warranted

    Grumpy or depressed? Disentangling typically developing adolescent mood from prodromal depression using experience sampling methods

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    Introduction: This study aimed at differentiating normative developmental turmoil from prodromal depressive symptoms in adolescence. Method: Negative and positive mood (daily) in different contexts (friends, home, school), and (subsequent) depressive symptoms were assessed in Dutch adolescents. Results & conclusion: Mixture modeling on one cross-sectional study, using a newly developed questionnaire (CSEQ; subsample 1a; n = 571; girls 55.9%; Mage = 14.17) and two longitudinal datasets with Experience Sampling Methods data (subsample 1b: n = 241; Mage = 13.81; 62.2% girls, sample 2: n = 286; 59.7% girls; Mage = 14.19) revealed three mood profiles: 18–24% "happy", 43–53% "typically developing", and 27–38% "at-risk". Of the “at-risk” profile between 12.5% and 25% of the adolescents scored above the clinical cut-off for depression. These mood profiles predicted later depressive symptoms, while controlling for earlier symptoms. In subsample 1b, parents were not always aware of the mental health status of their adolescent

    HBSC 2021. Gezondheid en welzijn van jongeren in Nederland

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    De mentale gezondheid van meisjes in Nederland is tussen 2017 en 2021 sterk verslechterd. Dat blijkt uit het Health Behaviour in School-aged Children (HBSC)-rapport, met daarin de resultaten van 20 jaar onderzoek naar het welzijn en de gezondheid van jongeren in Nederland. Vandaag wordt het rapport tijdens het symposium ‘Jong in de 21ste eeuw’ in Utrecht uitgereikt aan Hare Majesteit Koningin Máxima
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