The importance of chronicity and controllability of stress in the context of stress-illness relationships

The primary purpose of the present study was to increase our understanding of the roles of chronicity and controllability in the measurement of stress within the context of stress-illness relationships. Controllability and chronicity were assessed directly using a modified version of the Everyday Problems Scale. In addition to this scale, measures of depression, psychosomatic symptoms, and social support were administered to 128 women and 100 men. The results indicated that, for both men and women, the number of stressors was the best single predictor of symptoms. However, for women, chronicity and controllability of the stressors accounted for a significant amount of the variance in health outcomes over and above that accounted for by the number of stressors endorsed; for men, the addition of neither chronicity nor controllability consistently increased the strength of the association. While available social support was not found to influence the stress-illness relationships, greater willingness to utilize social support was associated with lower levels of depression.     

Controllable versus uncontrollable stressors bi-directionally modulate conditioned but not innate fear

Fear conditioning and fear extinction play key roles in the development and treatment of anxiety-related disorders, yet there is little information concerning experiential variables that modulate these processes. Here we examined the impact of exposure to a stressor in a different environment on subsequent fear conditioning and extinction, and whether the degree of behavioral control that the subject has over the stressor is of importance. Rats received a session of either escapable (controllable) tail shock (ES), yoked inescapable (uncontrollable) tail shock (IS), or control treatment (home cage, HC) 7 days before fear conditioning in which a tone and foot shock were paired. Conditioning was measured 24 h later. In a second experiment rats received ES, IS or HC 24 h after contextual fear conditioning. Extinction then occurred every day beginning 7 days later until a criterion was reached. Spontaneous recovery of fear was assessed 14 days after extinction. IS potentiated fear conditioning when given before fear conditioning, and potentiated fear responding during extinction when given after conditioning. Importantly, ES potently interfered with later fear conditioning, decreased fear responding during fear extinction, and prevented spontaneous recovery of fear. Additionally, we examined if the activation of the ventral medial prefrontal cortex (mPFCv) by ES is critical for the protective effects of ES on later fear conditioning. Inactivation of the mPFCv with muscimol at the time of the initial experience with control prevented ES-induced reductions in later contextual and auditory fear conditioning. Finally, we explored if the protective effects of ES extended to an unconditioned fear stimulus, ferret odor. Unlike conditioned fear, prior ES increased the fear response to ferret odor to the same degree as did IS.     

中药品质综合量化评控体系——标准评控力金字塔

中药品质评控是制约中药现代化发展的重要瓶颈问题。现有中药质控标准多为单一、定性的指标,缺少定量化和系统化评判,并且与临床安全性和有效性以及用量和用法等关联不密切。为此,笔者首次提出并构建了中药品质综合量化评控方法体系——标准评控力金字塔,并结合相关研究实例进行阐释,以期推动以临床为导向的中药整合创新研究,为提振中药品质及临床疗效提供前瞻性的管控策略与技术示例。     

A minimal energy control problem for second‐order linear hyperbolic systems with two independent variables

In this paper, we investigate controllability and minimal energy optimal control for Goursat–Darboux problem for the second‐order linear hyperbolic systems with two independent variables. The equation describes a relation between functions u: D→?^m and z: D→?ⁿ. We get an integral representation of the Goursat–Darboux problem by means of Riemann's matrix. The first half of the paper considers conditions under which there exists a control u for which the solution z of dynamics satisfies z(x₁, y₁) = p for any given p. The studied problem is reduced to the moments problem. The optimal control was found in a closed analytic form. Further, degeneracy of the matrix constructed by means of Riemann's matrix is shown to be a necessary and sufficient condition of controllability. Copyright © 2011 John Wiley & Sons, Ltd.     

Adolescents' perceptions of controllability and its relationship to explicit obesity bias

BACKGROUND: The purpose of the study was to assess adolescents' perceptions of controllability and its relation to weight stereotypes as a function of gender. METHODS: Two hundred and thirty‐one seventh and eighth graders from physical education classes completed a perception of controllability questionnaire and weight stereotype explicit scale ratings. RESULTS: Analysis of variance and chi‐square analyses indicated that adolescents had high perceptions of controllability, namely the perception that one can control one's weight with diet and exercise. Perceptions of controllability were weakly associated with the endorsement of stereotypes toward the overweight. Results from chi‐square analysis on individual statements related to causality of obesity indicated that participants may not have a complete understanding or be receiving appropriate messages about the etiology of obesity. Also, 2‐way chi‐square analyses indicated that boys more frequently believed in personal control than girls, and girls indicated more frequently that they were unsure whether obesity was children's fault. CONCLUSION: Teachers need to be cognizant of the messages that are relayed to students about the etiology of obesity if they are looking to positively impact students' healthy lifestyle behaviors and personal and social responsibility. Also, populations (eg, gender) may need to be considered when delivering these messages.     

Dynamics and control of state-dependent networks for probing genomic organization

A state-dependent dynamic network is a collection of elements that interact through a network, whose geometry evolves as the state of the elements changes over time. The genome is an intriguing example of a state-dependent network, where chromosomal geometry directly relates to genomic activity, which in turn strongly correlates with geometry. Here we examine various aspects of a genomic state-dependent dynamic network. In particular, we elaborate on one of the important ramifications of viewing genomic networks as being state-dependent, namely, their controllability during processes of genomic reorganization such as in cell differentiation.     

质量源于设计在银杏叶片制粒工艺中的应用(Ⅲ):基于设计空间的过程控制策略

该文在质量源于设计(QbD)理念的指导下,建立基于设计空间的银杏叶片高速剪切湿法制粒工艺控制策略,提高过程质量可控性和产品质量一致性。以颗粒中间体的中值粒径(D_(50))和松装密度(D_a)为关键质量属性(CQAs),采用失败模式和效应分析(FMEA)辨识潜在关键工艺参数(pCPPs)。采用Plackett-Burmann设计对潜在关键工艺参数进行筛选,确定黏合剂用量、湿混时间和湿混搅拌桨转速为关键工艺参数(CPPs)。在关键工艺参数范围内,采用Box-Behnken设计和二次多项式回归模型开发工艺设计空间。ANOVA分析显示回归模型的P0.05,且失拟值0.1,表明其可较好地定量描述CQAs和CPPs之间的关系。设计空间内任一CPPs组合均能分别将颗粒D_(50)和D_a控制在170~500μm和0.30~0.44 g·cm~(-3),进而满足银杏叶片机械性质要求。     

Behavioral control over shock blocks behavioral and neurochemical effects of later social defeat

Experience with behavioral control over tailshock (escapable shock, ES) has been shown to block the behavioral and neurochemical changes produced by later uncontrollable tail shock (inescapable shock, IS). The present experiments tested, in rats, whether the protective effect of control over tailshock extends beyond reducing the behavioral and neurochemical impact of a subsequent tailshock experience to stressors that are quite different. Social defeat (SD) was chosen as the second stress experience because it has few if any cues in common with tailshock. SD produced shuttlebox escape learning deficits (“learned helplessness”) and reduced juvenile social investigation 24 h later, as does IS. IS is notable for inducing a large increase in dorsal raphe nucleus (DRN) serotonergic (5-HT) activity as measured by extracellular levels of 5-HT within the DRN, and SD did so as well. ES occurring 7 days before SD blocked this SD-induced DRN activation, as well as the SD-induced interference with shuttlebox escape and reduction in social investigation. Prior exposure to yoked IS did not reduce the DRN 5-HT activation or later behavioral effects produced by SD, and thus the proactive stress-blunting effects of ES can be attributed to it's controllability. Thus, ES confers a very general protection to the impact of a subsequent stress experience.