Розрахунок довговічності матеріалів при нерегулярному непропорційному навантажуванні

Із метою розробки адекватних моделей для розрахунку довговічності аналізуються наведені в літературних джерелах експериментальні дані щодо малоциклової втоми сталі 304 та титанового сплаву ВТ9 під час деформування за складними історіями навантаження, що являють собою у просторі повних деформацій послідовність блоків різних за формою циклів. За базові використовуються чотири моделі накопичування пошкоджень та деформаційний критерій малоциклової втоми. Виконано порівняльний аналіз моделей прогнозування довговічності. Показано, що застосування удосконаленого нелінійного правила накопичування пошкоджень дозволяє покращити результати прогнозування довговічності, причому у більшій мірі для програм, що включають непропорційні цикли.С целью разработки адекватных моделей для расчета долговечности анализируются приведенные в литературных источниках данные по малоцикловой усталости стали 304 и титанового сплава ВТ9 в процессе деформирования по сложным историям нагружения, которые представляют собой в пространстве полных деформаций последовательность блоков разных по форме циклов. В качестве базовых применяются четыре модели накопления повреждений и деформационный критерий малоцикловой усталости. Проведен сравнительный анализ моделей прогнозирования долговечности. Показано, что применение усовершенствованного нелинейного правила накопления повреждений позволяет улучшить результаты прогнозирования долговечности, причем в большей степени для программ, которые включают непропорциональные циклы.We analyze the experimental data available in the literature on low-cycle fatigue of 304 steel and VT9 titanium alloy subjected to loads with complex loading histories, which are represented in the space of total deformations by a sequence of loading blocks consisting of cycles of various shapes. As models for the material life prediction, we use four models of damage accumulation, as well as the low-cycle fatigue deformation criterion. A comparative analysis of life prediction models is provided. It is shown that application of the refined nonlinear damage accumulation rule leads to the improvement of the life prediction results, which effect is more pronounced for loading programs containing nonproportional cycles

Is the Peer Presence Effect on Heightened Adolescent Risky Decision-Making only Present in Males?

Abstract: Social neurodevelopmental imbalance models posit that peer presence causes heightened adolescent risk-taking particularly during early adolescence. Evolutionary theory suggests that these effects would be most pronounced in males. However, the small but growing number of experimental studies on peer presence effects in adolescent risky decision-making showed mixed findings, and the vast majority of such studies did not test for the above-described gender and adolescent phase moderation effects. Moreover, most of those studies did not assess the criterion validity of the employed risky decision-making tasks. The current study was designed to investigate the abovementioned hypotheses among a sample of 327 ethnically-diverse Dutch early and mid-adolescents (49.80% female; Mage = 13.61). No main effect of peer presence on the employed risky-decision making task (i.e., the stoplight game) was found. However, the results showed a gender by peer presence moderation effect. Namely, whereas boys and girls engaged in equal levels of risks when they completed the stoplight game alone, boys engaged in more risk-taking than girls when they completed this task together with two same-sex peers. In contrast, adolescent phase did not moderate peer presence effects on risk-taking. Finally, the results showed that performance on the stoplight game predicted self-reported real-world risky traffic behavior, alcohol use and delinquency. Taken together, using a validated task, the present findings demonstrate that individual differences (i.e., gender) can determine whether the social environment (i.e., peer presence) affect risk-taking in early- and mid-adolescents. The finding that performance on a laboratory risky decision-making task can perhaps help identify adolescents that are vulnerable to diverse types of heightened risk behaviors is an important finding for science as well as prevention and intervention efforts

Borderline personality disorder in young people: associations with support and negative interactions in relationships with mothers and a best friend

BACKGROUND: Impaired interpersonal functioning has been highlighted as a core feature of borderline personality disorder (BPD). Adolescence and young adulthood form important developmental stages within both the emergence of BPD and the development of interpersonal functioning, which takes place mostly in relationships with parents and friends. This study aimed to: (i) investigate relations between BPD symptoms and both supportive and negative interactions with mothers and best friends; (ii) investigate whether the relations were moderated by age; (iii) test the robustness of our findings by comparing the results based on self-reports with results from a subsample in which supportive and negative interactions with mothers were rated by the mother. METHODS: 312 young people referred to mental healthcare completed self-report measures on BPD and supportive and negative interactions. Multiple regression analyses were conducted to examine the relations between BPD features and perceived supportive and negative interactions with mothers and a best friend, and to investigate whether these relations were moderated by age. Robustness of our findings was studied in a subsample (n = 104), by using a multi-informant design in maternal report on supportive and negative interactions with mothers. RESULTS: Multiple regression analyses demonstrated that negative interactions with mothers as well as with a best friend were related to more BPD symptoms in young people. Supportive interactions were not related to BPD symptoms. Both BPD and quality of relations were not related to age. In a subsample in which supportive and negative interactions with mothers were rated by the mother, the maternal report showed slightly different results. In this model, both supportive and negative interactions with a best friend were positively related, whereas interactions with mothers were not related to BPD symptoms in young people. CONCLUSIONS: Results highlight the importance of relationships with mothers and a best friend during adolescence and young adulthood. Given that BPD often emerges during this developmental phase, future research is needed to clarify how quality of relationships could alter pathways toward BPD in young people. TRIAL REGISTRATION: Not applicable

Is the Peer Presence Effect on Heightened Adolescent Risky Decision-Making only Present in Males?

Abstract: Social neurodevelopmental imbalance models posit that peer presence causes heightened adolescent risk-taking particularly during early adolescence. Evolutionary theory suggests that these effects would be most pronounced in males. However, the small but growing number of experimental studies on peer presence effects in adolescent risky decision-making showed mixed findings, and the vast majority of such studies did not test for the above-described gender and adolescent phase moderation effects. Moreover, most of those studies did not assess the criterion validity of the employed risky decision-making tasks. The current study was designed to investigate the abovementioned hypotheses among a sample of 327 ethnically-diverse Dutch early and mid-adolescents (49.80% female; Mage = 13.61). No main effect of peer presence on the employed risky-decision making task (i.e., the stoplight game) was found. However, the results showed a gender by peer presence moderation effect. Namely, whereas boys and girls engaged in equal levels of risks when they completed the stoplight game alone, boys engaged in more risk-taking than girls when they completed this task together with two same-sex peers. In contrast, adolescent phase did not moderate peer presence effects on risk-taking. Finally, the results showed that performance on the stoplight game predicted self-reported real-world risky traffic behavior, alcohol use and delinquency. Taken together, using a validated task, the present findings demonstrate that individual differences (i.e., gender) can determine whether the social environment (i.e., peer presence) affect risk-taking in early- and mid-adolescents. The finding that performance on a laboratory risky decision-making task can perhaps help identify adolescents that are vulnerable to diverse types of heightened risk behaviors is an important finding for science as well as prevention and intervention efforts

Новые подходы к изучению русского романтизма в литературоведении 1990-х годов

В статье анализируются теоретические аспекты сущности понятия «романтизм», дается аналитический обзор литературоведческих исследований о русском романтизме, обобщаются основные направления в изучении русского романтизма.У статті аналізуються теоретичні аспекти сутності поняття “романтизм”, дається аналітичний огляд літературознавчих досліджень про російський романтизм, узагальнюються основні напрямки у вивченні російського романтизму.The article deals with the theoretical aspects of the real meaning of “Romanticism”. It is given here an analytical revision of the history literary researches of Russian romanticism; anylized the main aspects of new approaches to studying Russian romanticism

Differentiating BPD in adolescents with NSSI disorder: the role of adverse childhood experiences and current social relationships

Background: As borderline personality disorder (BPD) is increasingly considered a lifespan developmental disorder, we need to focus on risk factors and precursors in the developmental pathways to BPD, in order to enable early detection and intervention. Within this developmental pathway, adolescence is a crucial phase in the light of the manifestation of the disorder. Relational factors such as adverse childhood experiences and current relational problems can be considered important in adolescents who are at-risk for BPD. Nonsuicidal self-injury (NSSI) is a key precursor for adolescent BPD and one of the most promising targets for early detection and intervention of BPD. Methods: In a clinical sample of 152 adolescents engaging in nonsuicidal self-injury (NSSI) disorder referred to mental healthcare in Germany, this study investigated whether we can differentiate who has BPD from 1) adverse childhood experiences; and 2) the quality of current relationships, both with parents and peers. BPD was assessed both categorically as a dichotomized score and dimensionally as a continuous score. Results: More adverse childhood experiences, but not low quality of current social relationships, were related to more BPD symptoms and an increased risk for meeting full criteria for BPD. In the dimensional model, current social relationship quality with parents and peers did not show a moderating (protecting or aggravating) effect on the association between adverse childhood experiences and BPD. Using a categorical approach, however, the association between childhood adversity and meeting full criteria for BPD was higher in individuals reporting higher quality of current parent-child relationship. Conclusions: These results highlight adverse childhood experiences as risk factors of BPD, while the role of current social relationships seems more complex

Stressful events and psychological difficulties:testing alternative candidates for sensitivity

The current study investigated the longitudinal, reciprocal associations between stressful events and psychological difficulties from early childhood to mid-adolescence. Child age, sex, prenatal maternal anxiety, and difficult temperament were tested as sources of sensitivity, that is, factors that may make children more sensitive to stressful life events. Analyses were based on data from 10,417 children from a prospective, longitudinal study of child development. At ages 4, 7, 9, 11, and 16 years, stressful events and psychological difficulties were measured. Prenatal anxiety was measured at 32 weeks of gestation and difficult temperament was measured at 6 months. Children exposed to stressful events showed significantly increased psychological difficulties at ages 7 and 11 years; there was consistent evidence of a reciprocal pattern: psychological difficulties predicted stressful events at each stage. Analyses also indicated that the associations between stressful events and psychological difficulties were stronger in girls than in boys. We found no evidence for the hypothesis that prenatal anxiety or difficult temperament increased stress sensitivity, that is, moderated the link between life events and psychological difficulties. The findings extend prior work on stress exposure and psychological difficulties and highlight the need for additional research to investigate sources of sensitivity and the mechanisms that might underlie differences in sensitivity to stressful events

The co-occurrence of autism spectrum disorder and attention-deficit/hyperactivity disorder symptoms in parents of children with ASD or ASD with ADHD

Background: Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) share about 50-72% of their genetic factors, which is the most likely explanation for their frequent co-occurrence within the same patient or family. An additional or alternative explanation for the co-occurrence may be (cross-)assortative mating, e.g., the tendency to choose a partner that is similar or dissimilar to oneself. Another issue is that of parent-of-origin effect which refers to the possibility of parents differing in the relative quantity of risk factors they transmit to the offspring. The current study sets out to examine (cross-)assortative mating and (cross-)parent-of-origin effects of ASD and ADHD in parents of children with either ASD or ASD with ADHD diagnosis. Methods: In total, 121 families were recruited in an ongoing autism-ADHD family genetics project. Participating families consisted of parents and at least one child aged between 2 and 20 years, with either autistic disorder, Asperger disorder or PDD-NOS, and one or more biological siblings. All children and parents were carefully screened for the presence of ASD and ADHD. Results: No correlations were found between maternal and paternal ASD and ADHD symptoms. Parental ASD and ADHD symptoms were predictive for similar symptoms in the offspring, but with maternal hyperactive-impulsive symptoms, but not paternal symptoms, predicting similar symptoms in daughters. ASD pathology in the parents was not predictive for ADHD pathology in the offspring, but mother's ADHD pathology was predictive for offspring ASD pathology even when corrected for maternal ASD pathology. Conclusions: Cross-assortative mating for ASD and ADHD does not form an explanation for the frequent co-occurrence of these disorders within families. Given that parental ADHD is predictive of offspring' ASD but not vice versa, risk factors underlying ASD may overlap to a larger degree with risk factors underlying ADHD than vice versa. However, future research is needed to clarify this issue. Keywords: Assortative mating, parent-of-origin effect, autism spectrum disorder, attention-deficit/hyperactivity disorder

Externalizing behaviors in preadolescents: familial risk to externalizing behaviors and perceived parenting styles

The aim was to investigate the contribution of familial risk to externalizing behaviors (FR-EXT), perceived parenting styles, and their interactions to the prediction of externalizing behaviors in preadolescents. Participants were preadolescents aged 10–12 years who participated in TRAILS, a large prospective population-based cohort study in the Netherlands (N = 2,230). Regression analyses were used to determine the relative contribution of FR-EXT and perceived parenting styles to parent and teacher ratings of externalizing behaviors. FR-EXT was based on lifetime parental externalizing psychopathology and the different parenting styles (emotional warmth, rejection, and overprotection) were based on the child’s perspective. We also investigated whether different dimensions of perceived parenting styles had different effects on subdomains of externalizing behavior. We found main effects for FR-EXT (vs. no FR-EXT), emotional warmth, rejection, and overprotection that were fairly consistent across rater and outcome measures. More specific, emotional warmth was the most consistent predictor of all outcome measures, and rejection was a stronger predictor of aggression and delinquency than of inattention. Interaction effects were found for FR-EXT and perceived parental rejection and overprotection; other interactions between FR-EXT and parenting styles were not significant. Correlations between FR-EXT and perceived parenting styles were absent or very low and were without clinical significance. Predominantly main effects of FR-EXT and perceived parenting styles independently contribute to externalizing behaviors in preadolescents, suggesting FR-EXT and parenting styles to be two separate areas of causality. The relative lack of gene–environment interactions may be due to the epidemiological nature of the study, the preadolescent age of the subjects, the measurement level of parenting and the measurement level of FR-EXT, which might be a consequence of both genetic and environmental factors

Fusion of metabolomics and proteomics data for biomarkers discovery: case study on the experimental autoimmune encephalomyelitis

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