High-temperature strength of boron carbide with Pt grain-boundary framework in situ synthesized during spark plasma sintering

Grain boundaries, twins, and defects are considered to influence the thermomechanical behavior of any covalent ceramic, as a result, monolithic B₄C samples show different curve shapes of bending strength vs temperature and the present theoretical models fail to fit them over the entire temperature range. To overcome these issues, we fabricated a novel high-density boron carbide and evaluated its high-temperature bending strength. The as-obtained ceramic is composed of boron carbide grains and a fine grain-boundary metal Pt framework. The material shows a decreased strength, which is due to a non-linear increase in the volume expansion coefficient of the B₄C. Recovery in strength above 1000 °C is due to the presence of twins, their growth and rearrangements. We consider twins rearrangements are the pieces of evidence for a novel ‘micro’ mechanism of high-temperature stress accommodation for the boron carbide bulks.     

基于数字孪生的船用燃气轮机健康管理工业互联网平台

为了解决现阶段船用燃气轮机健康管理系统的数据准确率低、实效性差、各部件间数据和信息无法实现互联互通以及智能化故障诊断和预测程度低的问题,调研了现阶段数字孪生在健康管理领域的应用现状。基于成熟的五维数字孪生模型,阐述了物理实体、虚拟实体、数据孪生中心、健康管理功能系统的运行机制及交互机制。在此基础上,借鉴现有典型工业互联网平台的架构和功能,构建了基于数字孪生的船用燃气轮机健康管理工业互联网平台,通过与传统健康管理系统进行对比分析总结其优势。结果表明：该平台能够满足全生命周期健康管理过程中数据和模型信息的实时交互和动态更新,可打通健康管理系统中多个部件数字孪生模型闭环,并能为未来健康管理系统的发展和建设提供新的发展思路。     

Father-adolescent relationships and the role of genotype-environment correlation.

This study uses 2 samples of adolescents and parents--the child-based Nonshared Environment in Adolescent Development project (NEAD; D. Reiss, J. M. Neiderhiser, E. Hetherington, & R. Plomin, 2000; N = 395 families) and the parent-based Twin and Offspring Study in Sweden (TOSS; N = 909 twin family pairs)--to investigate passive and evocative genotype-environment correlation (rGE) on fathering. Both samples used the same measures of positivity, negativity, control, and monitoring. A previous report examining mothering found evidence for passive rGE for positivity and monitoring, and evocative rGE for negativity and control, although both types of rGE were suggested in many cases. The current report focuses on fathering. Father reports of positivity and control are influenced by evocative rGE, whereas father reports of negativity and monitoring are influenced by both passive and evocative rGE. Adolescent reports of father's positivity and negativity were influenced by both evocative and passive rGE, and control and monitoring by passive rGE. The most notable difference in findings for fathers and mothers is for positivity and the presence of rGE for father's control and monitoring. These findings and their implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Delinquent peer affiliation and conduct problems: A twin study.

Many putative environmental risks correlate with individuals' genotypes. The association between delinquent peer affiliation and conduct problems may occur because of shared genetic liability. Five hundred fifty three monozygotic and 558 dizygotic twin pairs, aged 11 to 18 years, were assessed for delinquent peer affiliation and conduct problems. The authors investigated whether genes contribute to both delinquent peer affiliation and the correlation between delinquent peer affiliations and conduct problems. Delinquent peer affiliation was influenced by genetic, shared environmental, and nonshared environmental factors; genetic factors also contributed to the correlation between delinquent peer affiliations and conduct problems, providing evidence for genotype-environment correlation. The magnitude of the genetic variance of conduct problems was contextually dependent on levels of delinquent peer affiliation and was greater at higher levels of delinquent peer affiliation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender differences and developmental change in externalizing disorders from late adolescence to early adulthood: A longitudinal twin study.

Using data from over 1,000 male and female twins participating in the Minnesota Twin Family Study, the authors examined developmental change, gender differences, and genetic and environmental contributions to the symptom levels of four externalizing disorders (adult antisocial behavior, alcohol dependence, nicotine dependence, and drug dependence) from ages 17 to 24. Both men and women increased in symptoms for each externalizing disorder, with men increasing at a greater rate than women, such that a modest gender gap at age 17 widened to a large one at age 24. Additionally, a mean-level gender difference on a latent Externalizing factor could account for the mean-level gender differences for the individual disorders. Biometric analyses revealed increasing genetic variation and heritability for men but a trend toward decreasing genetic variation and increasing environmental effects for women. Results illustrate the importance of gender and developmental context for symptom expression and the utility of structural models to integrate general trends and disorder-specific characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

In search of shared and nonshared environmental factors in security of attachment: A behavior-genetic study of the association between sensitivity and attachment security.

The current article presents results from a twin study of genetic and environmental components of maternal sensitivity and infant attachment and their association. The sample consisted of 136 twin pairs from 2 sites: Leiden, the Netherlands, and London, UK. Maternal sensitivity was assessed in the home at 9-10 months, and infant attachment security was observed in the laboratory at 12 months. The study yielded little evidence that genetic factors are involved in variations between twins in maternal sensitivity ratings but did find that shared variance in maternal sensitivity was able to account for some of the similarity between twins in attachment security. Weak nonshared associations between sensitivity and attachment appeared to suppress the magnitude of the correlation between attachment and sensitivity in twin children. The results could indicate that the attachment security of one twin may depend on the relationship the parent has with the other twin. The results are brought to bear on the validity of attachment theory as a theory of primarily shared environmental effects in children's development and the continuing challenge posed to attachment theory by within-family differences in socioemotional processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sexual behavior in young adulthood: A population-based twin study.

Objective: With behavior genetic analyses of data from young adult twins, we evaluated theoretical perspectives that differentially emphasize biological dispositions, social/cultural factors, or universal pathways to explain individual differences in sexual behaviors. Design: We fit biometric sex limitation models to three aspects of sexual behavior reported by 4,925 Finnish twins ages 23-27. Main Outcome Measure: From a postal questionnaire, we obtained self-report information on initiation/abstinence of sexual intercourse, onset age, and number of sexual partners. Results: Genetic and non-shared environmental influences were significant for all three measures. There were trends for common environmental influences on initiation and, in females, age at first intercourse. Some differential effects in males and females were found. Results comparing onset age and number of partners among experienced twins from pairs concordant and discordant for initiation found genetic and environmental influences on initiation/abstinence overlapped those found for the other aspects of sexual behavior. Conclusions: These results document genetic variation in individual differences in sexual behavior of young adults. Incorporating genetic dispositions into integrated models of sexual behavior will facilitate more effective health promotion and risk taking intervention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

(100)高氯T颗粒乳剂中非T颗粒的产生

(100)高氯T颗粒乳剂是一种新型的T颗粒感光乳剂，颗粒的两个(100)主晶面为正方形或矩形。乳剂中常出现棒状大颗粒、四面体状大颗粒、厚颗粒以及立方体和近似球形的小颗粒等非T颗粒。非T颗粒的存在降低了T颗粒的比例，影响乳剂的照相性能。本文通过在制备过程中取样、观察，分析了非T颗粒产生的时间、成因、影响因素以及减少非T颗粒的措施。     

Genetic and environmental effects of serial naming and phonological awareness on early reading outcomes.

The current study involved 281 early-school-age twin pairs (118 monozygotic, 163 same-sex dizygotic) participating in the ongoing Western Reserve Reading Project (S. A. Petrill, K. Deater-Deckard, L. A. Thompson, & C. Schatschneider, 2006). Twins were tested in their homes by separate examiners on a battery of reading-related skills including phonological awareness, rapid automatized naming, word knowledge, and phonological decoding. Results suggested that a core genetic factor accounted for a significant portion of the covariance between phonological awareness, rapid naming, and reading outcomes. However, shared environmental influences related to phonological awareness were also associated with reading skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

大数据与数字孪生驱动的智慧校园集成设计研究

目的 为解决智慧城市集成化设计中仍存在数据孤岛与智慧决策的相关问题,因此设计了一套以智慧校园创新服务生态为导向的园区集成设计方案,为大数据与数字孪生驱动的智慧城市构建提供建设新思路。方法 研究通过建立智慧校园数据的标准信息模型,采用结构化数据为主的物联网传感器进行部署,并利用大数据与深度学习方法实现校园的智慧大脑,开发了基于Web 3D与数字孪生驱动的人机共融可视化平台,从可操作性角度制定了可执行、可落地的智慧校园设计。结果 从大数据特点切入对智慧校园的构建状况进行分析,建立智慧校园数据的标准化模型,设计了基于GRU-CNN深度学习智慧大脑的Web 3D与数字孪生驱动可视化平台。实验表明该系统具有数据可视化与智能决策功能,能提供给用户沉浸式、多维动态的人机共融交互体验。结论 利用大数据驱动的数字孪生可视化平台可以实现校区一体化运行,增强校园结构的智能化、高效化和人性化,提高使用效率。智慧校园集成平台设计同时可以推动现代化城市进一步完成数据互通互联、数据可视化、智慧服务管理新模式。为当前智慧城市的建设提供技术及理论参照。