Parenting and community background and variation in women's life-history development.

For a community sample of 623 low-income women (mean age = 26.9 years), the authors use life-history theory to explore relations between parenting and community background and timing of reproductive development and sexual behaviors. Among other patterns, reported levels of paternal involvement during childhood were related to delayed menarche and ages at 1st sexual intercourse and 1st childbirth. The relation between parental investment and women's reproductive delay varied with estimates of wealth in the community in which the participants grew up. The results suggest that parents increased their investment as the level of community wealth increased, and in ways that likely facilitated women's ability to compete for social status in adulthood. Implications for future research on the relation between parenting and child outcomes are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toughened interpenetrating polymer network materials based on unsaturated polyester and epoxy

Simultaneous interpenetrating polymer networks (IPNs) based on epoxy (diglycidyl ether of bisphenol A) and unsaturated polyester (UP) were prepared by using m‐xylenediamine and benzoyl peroxide as curing agents. A single glass transition temperature for each IPN was observed with differential scanning calorimetry, which suggests good compatibility of epoxy and UP. This compatibility was further confirmed by the single damping peak of the rheometric dynamic spectroscopy. Curing behaviors were studied with dynamic differential scanning calorimetry, and the curing rates were measured with a Brookfield RTV viscometer. It was noted that an interlock between the two growing networks did exist and led to a retarded viscosity increase. However, the hydroxyl end groups in UP catalyzed the curing reaction of epoxy; in some IPNs where the hydroxyl concentration was high enough, such catalytic effect predominated the network interlock effect, leading to fast viscosity increases. In addition, the entanglement of the two interlocked networks played an important role in cracking energy absorption and reflected in a toughness improvement. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 585–592, 1999     

单跨无洞框支墙梁抗震受力性能研究

以单跨无洞框支墙梁为研究对象 ,通过两榀接近足尺的墙梁试件的试验研究 ,揭示了竖向荷载作用下 ,以及竖向荷载与水平荷载联合作用下框架支承墙梁的基本受力特征。研究表明 ,竖向荷载单独作用下 ,墙梁存在明显的组合作用 ,构造柱可帮助砌体承担相当比例的竖向荷载 ;在水平力作用下 ,作用在墙梁顶面的均匀分布竖向荷载在向下传递至托梁顶面的过程中 ,会偏移至倾覆弯矩受压一侧梁端 ,并可能使该侧墙角砌体压碎以及梁端明显的剪切破坏。     

Mechanical behaviors of notched composite laminates

0　ＩＮＴＲＯＤＵＣＴＩＯＮＦｏｒｔｈｅｉｒａｄｖａｎｔａｇｅｓｏｆｓｔｒｅｎｇｔｈ ｔｏ ｗｅｉｇｈｔａｎｄｓｔｉｆｆ ｎｅｓｓ ｔｏ ｗｅｉｇｈｔ,ｃｏｍｐｏｓｉｔｅｍａｔｅｒｉａｌｓｈａｖｅｂｅｅｎｕｓｅｄｗｉｄｅｌｙｉｎｔｈｅｆｉｅｌｄｓｏｆａｅｒｏｎａｕｔｉｃａｌａｎｄａｓｔｒｏｎａｕｔｉｃａｌｅｎｇｉｎｅｅｒｉｎｇ .Ｆｌａｔｃｏｕｐｏｎｓｐｅｃｉｍｅｎｓａｒｅｏｆｔｅｎｕｓｅｄｔｏｍｅａｓｕｒｅｔｈｅｍｅ ｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｃｏｍｐｏｓｉｔｅｌａｍｉｎａｔｅｓ .Ｂｅｃａ…     

Simultaneous Antagonism at H3R/D2R/D3R Reduces Autism-like Self-Grooming and Aggressive Behaviors by Mitigating MAPK Activation in Mice

Dysregulation in brain neurotransmitters underlies several neuropsychiatric disorders, e.g., autism spectrum disorder (ASD). Also, abnormalities in the extracellular-signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) pathway pave the way for neuroinflammation, neurodegeneration, and altered learning phenotype in ASD. Therefore, the effects of chronic systemic administration of the multiple-targeting antagonist ST-713 at the histamine H3 receptor (H3R) and dopamine D2/D3 receptors (D2/D3R) on repetitive self-grooming, aggressive behaviors, and abnormalities in the MAPK pathway in BTBR T + Itpr3tf/J (BTBR) mice were assessed. The results showed that ST-713 (2.5, 5, and 10 mg/kg, i.p.) mitigated repetitive self-grooming and aggression in BTBR mice (all p < 0.05), and the ameliorative effects of the most promising dose of ST-713 (5 mg/kg, i.p.) on behaviors were completely abrogated by co-administration of the H3R agonist (R)-α-methylhistamine or the anticholinergic drug scopolamine. Moreover, the elevated levels of several MAPK pathway proteins and induced proinflammatory markers such as tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), and IL-6 were significantly suppressed following chronic administration of ST-713 (5 mg/kg, i.p.) (all p < 0.01). Furthermore, ST-713 significantly increased the levels of histamine and dopamine in hippocampal tissue of treated BTBR mice (all p < 0.01). The current observations signify the potential role of such multiple-targeting compounds, e.g., ST-713, in multifactorial neurodevelopmental disorders such as ASD.     

RH真空室内气泡行为的研究

Ruhrstahl-Hereaeus (RH)上升管内的气液两相流是整个装置的重要动力源,并对钢液的流动、混匀及精炼过程有重要影响.上升管及真空室内的气液两相流决定了钢包内钢液的流动状态,为了研究真空室及上升管内气液两相流,通过1:6的300 t RH的物理模型模拟了RH上升管及真空室内气泡行为过程,并测量了RH循环流量的变化用于计算上升管内含气率以及气泡运动速度最终得到气泡在真空室内的停留时间,同时记录了气泡在真空室内的存在形式.气泡在真空室的存在形式的主要影响因素为提升气体流量,研究发现了气泡从规则独立的大气泡经历聚合长大,碰撞破碎成小气泡,最后变成小气泡和不规则大气泡共存的现象.液面高度达到80 mm之后,气泡在真空室内的停留时间达到一个平衡值,不再随真空室液面高度的增加而发生改变.当提升气体量达3000 L·min^-1,气泡停留时间减小趋势弱,对应3000 L·min^-1情况下,真空室内气泡开始聚合长大.研究认为对于300 t RH的真空室液面高度应为80 mm,提升气体量应在3500 L·min^-1左右,优化后,脱碳时间由原工艺的21.4 min缩短至现工艺的17.5 min.     

钢结构箱形柱与梁异型节点设计方法研究

针对大型厂房框排架结构中通常存在变梁变柱异型节点的实际情况,对6个钢结构箱形柱与梁异型节点模型进行拟静力试验,研究了钢结构异型节点的破坏机理和力学行为,建立了基于塑性铰理论的钢结构异型节点力学模型,提出了该类异型节点的设计方法及构造建议。试验与计算对比表明：可按小核心区为常规节点计算梁端的抗弯承载力;在验算节点域强度时可只对小核心区进行验算,且在保证节点域强度的前提下,只需对小核心区的抗剪承载力进行验算。该方法为钢结构异型节点的合理设计提供了依据。     

A method for 3D simulation of internal gas effects on thermal-mechanical behaviors in nuclear fuel elements

A new method for three-dimensional simulation of the interaction between the gas and the solid around is developed.The effects of the gas on the thermal-mechanical behaviors within the surrounded solid are performed by replacing the internal gas with an equivalent solid in the modeling,which can make it convenient to simulate the thermal-mechanical coupling effects in the solid research objects with gases in them.The applied thermal expansion coefficient,Young’s modulus and Poisson’s ratio of the equivalent solid material are derived.A series of tests have been conducted;and the proposed equivalent solid method to simulate the gas effects is validated.     

Alteration of the Early Development Environment by Maternal Diet and the Occurrence of Autistic-like Phenotypes in Rat Offspring

Epidemiological and preclinical studies suggest that maternal obesity increases the risk of autism spectrum disorder (ASD) in offspring. Here, we assessed the effects of exposure to modified maternal diets limited to pregnancy and lactation on brain development and behavior in rat offspring of both sexes. Among the studied diets, a maternal high-fat diet (HFD) disturbed the expression of ASD-related genes (Cacna1d, Nlgn3, and Shank1) and proteins (SHANK1 and TAOK2) in the prefrontal cortex of male offspring during adolescence. In addition, a maternal high-fat diet induced epigenetic changes by increasing cortical global DNA methylation and the expression of miR-423 and miR-494. As well as the molecular changes, behavioral studies have shown male-specific disturbances in social interaction and an increase in repetitive behavior during adolescence. Most of the observed changes disappeared in adulthood. In conclusion, we demonstrated the contribution of a maternal HFD to the predisposition to an ASD-like phenotype in male adolescent offspring, while a protective effect occurred in females.