45 research outputs found

    Monte Carlo Methods for Estimating Interfacial Free Energies and Line Tensions

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    Excess contributions to the free energy due to interfaces occur for many problems encountered in the statistical physics of condensed matter when coexistence between different phases is possible (e.g. wetting phenomena, nucleation, crystal growth, etc.). This article reviews two methods to estimate both interfacial free energies and line tensions by Monte Carlo simulations of simple models, (e.g. the Ising model, a symmetrical binary Lennard-Jones fluid exhibiting a miscibility gap, and a simple Lennard-Jones fluid). One method is based on thermodynamic integration. This method is useful to study flat and inclined interfaces for Ising lattices, allowing also the estimation of line tensions of three-phase contact lines, when the interfaces meet walls (where "surface fields" may act). A generalization to off-lattice systems is described as well. The second method is based on the sampling of the order parameter distribution of the system throughout the two-phase coexistence region of the model. Both the interface free energies of flat interfaces and of (spherical or cylindrical) droplets (or bubbles) can be estimated, including also systems with walls, where sphere-cap shaped wall-attached droplets occur. The curvature-dependence of the interfacial free energy is discussed, and estimates for the line tensions are compared to results from the thermodynamic integration method. Basic limitations of all these methods are critically discussed, and an outlook on other approaches is given

    Problematic pornography use across countries, genders, and sexual orientations: Insights from the International Sex Survey and comparison of different assessment tools.

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    Problematic pornography use (PPU) is a common manifestation of the newly introduced Compulsive Sexual Behavior Disorder diagnosis in the 11th edition of the International Statistical Classification of Diseases and Related Health Problems. Although cultural, gender- and sexual orientation-related differences in sexual behaviors are well documented, there is a relative absence of data on PPU outside Western countries and among women as well as gender- and sexually-diverse individuals. We addressed these gaps by (a) validating the long and short versions of the Problematic Pornography Consumption Scale (PPCS and PPCS-6, respectively) and the Brief Pornography Screen (BPS) and (b) measuring PPU risk across diverse populations. Using data from the pre-registered International Sex Survey [n = 82 243; mean age (M <sub>age</sub> ) = 32.4 years, standard deviation = 12.5], a study across 42 countries from five continents, we evaluated the psychometric properties (i.e. factor structure, measurement invariance, and reliability) of the PPCS, PPCS-6, and BPS and examined their associations with relevant correlates (e.g. treatment-seeking). We also compared PPU risk among diverse groups (e.g. three genders). The PPCS, PPCS-6, and BPS demonstrated excellent psychometric properties [for example, comparative fit index = 0.985, Tucker-Lewis Index = 0.981, root mean square error of approximation = 0.060 (90% confidence interval = 0.059-0.060)] in the confirmatory factor analysis, with all PPCS' inter-factor correlations positive and strong (rs = 0.72-0.96). A total of 3.2% of participants were at risk of experiencing PPU (PPU+) based on the PPCS, with significant country- and gender-based differences (e.g. men reported the highest levels of PPU). No sexual orientation-based differences were observed. Only 4-10% of individuals in the PPU+ group had ever sought treatment for PPU, while an additional 21-37% wanted to, but did not do so for specific reasons (e.g. unaffordability). This study validated three measures to assess the severity of problematic pornography use across languages, countries, genders, and sexual orientations in 26 languages: the Problematic Pornography Consumption Scale (PPCS, and PPCS-6, respectively), and the Brief Pornography Screen (BPS). The problematic pornography use risk is estimated to be 3.2-16.6% of the population of 42 countries, and varies among different groups (e.g. genders) and based on the measure used

    Evaluating the factor structure and measurement invariance of the 20-item short version of the UPPS-P Impulsive Behavior Scale across multiple countries, languages, and gender identities

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    The UPPS-P Impulsive Behavior Model and the various psychometric instruments developed and validated based on this model are well established in clinical and research settings. However, evidence regarding the psychometric validity, reliability, and equivalence across multiple countries of residence, languages, or gender identities, including gender-diverse individuals, is lacking to date. Using data from the International Sex Survey (N = 82,243), confirmatory factor analyses and measurement invariance analyses were performed on the preestablished five-factor structure of the 20-item short version of the UPPS-P Impulsive Behavior Scale to examine whether (a) psychometric validity and reliability and (b) psychometric equivalence hold across 34 country-of-residence-related, 22 language-related, and three gender-identity-related groups. The results of the present study extend the latter psychometric instrument's well-established relevance to 26 countries, 13 languages, and three gender identities. Most notably, psychometric validity and reliability were evidenced across nine novel translations included in the present study (i.e., Croatian, English, German, Hebrew, Korean, Macedonian, Polish, Portuguese-Portugal, and Spanish-Latin American) and psychometric equivalence was evidenced across all three gender identities included in the present study (i.e., women, men, and gender-diverse individuals)

    Cross-Cultural Validation of the Binge Eating Disorder Screener-7 (BEDS-7) Across 42 Countries.

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    This study aimed to evaluate the reliability and validity of the Binge Eating Disorder Screener-7 (BEDS-7) across 42 countries and 26 languages, assessing its reliability and validity as a screening tool for binge-eating disorder (BED) in diverse cultural contexts. Specifically, it sought to enhance early recognition of BED symptoms in primary care settings globally, contributing to a standardized framework for assessing BED. The International Sex Survey, a cross-sectional online study, was conducted in 42 countries and 26 languages. A diverse community sample of 82,243 participants, aged 18 years or older, completed the BEDS-7 and measures of sexuality, mental health, substance use, and sociodemographic characteristics. Confirmatory factor analyses and tests of measurement invariance were employed to evaluate the reliability and validity of the BEDS-7 across languages, countries, genders, and sexual orientations. The BEDS-7 demonstrated scalar factorial invariance across languages and countries, indicating consistent factor loadings and item intercepts. In contrast, the screener showed residual invariance across gender and sexual orientation groups, supporting its robustness across these demographics. Kruskal-Wallis tests revealed significant differences in BED symptoms across languages, countries, genders, and sexual orientations, with the highest BED scores observed among queer, pansexual, and gender-diverse individuals. The BEDS-7 also demonstrated adequate reliability (Cronbach's alpha > 0.80) and moderate criterion validity. The findings provide further evidence of the reliability and validity of the BEDS-7 as a potential screening tool for identifying probable cases of BED globally, facilitating early intervention in primary care settings

    The Cancer Genome Atlas Comprehensive Molecular Characterization of Renal Cell Carcinoma

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    Renal cell carcinoma(RCC) is not a single disease, but several histologically defined cancers with different genetic drivers, clinical courses, and therapeutic responses. The current study evaluated 843 RCC from the three major histologic subtypes, including 488 clear cell RCC, 274 papillary RCC, and 81 chromophobe RCC. Comprehensive genomic and phenotypic analysis of the RCC subtypes reveals distinctive features of each subtype that provide the foundation for the development of subtype-specific therapeutic and management strategies for patients affected with these cancers. Somatic alteration of BAP1, PBRM1, and PTEN and altered metabolic pathways correlated with subtype-specific decreased survival, while CDKN2A alteration, increased DNA hypermethylation, and increases in the immune-related Th2 gene expression signature correlated with decreased survival within all major histologic subtypes. CIMP-RCC demonstrated an increased immune signature, and a uniform and distinct metabolic expression pattern identified a subset of metabolically divergent (MD) ChRCC that associated with extremely poor survival
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