分类： 心理学 >> 应用心理学 提交时间： 2023-09-14
摘要： Objective: Nowadays, young adults are facing stressors from several aspects. They have already become the most anxious groups in Chinese society and in risk of developing a series of anxiety disorders. The theory of challenge-hindrance stress was proposed to explain the positive and negative outcomes of different stressors. It has been widely tested mostly in the field of organization and management. In the current study, we used the challenge-hindrance stress theory to clarify the association between stress in daily life and anxiety. We also examined the HPA-axis function buffering the influence of daily stress on anxiety.Methods: we used the edited Chinese version of challenge-hindrance stress scales to measure challenge and hindrance stress over 6 months. The level of anxiety was measured by state-trait anxiety inventory. We also carried out a Trier Social Stress Test (TSST) in laboratory and recorded the change of cortisol level during the 60 minutes right after the acute stress.Results: Results show that the recent level of hindrance stress positively predicts trait anxiety, but the level of challenge stress does not predict trait anxiety. It is also found that, the cortisol decline rate during the recovery of acute stress moderates the association between stress and anxiety. To be exact, individuals with low cortisol decline rate could not recover to baseline level even after rather long rest, and hindrance stress in their lives would lead to higher level of anxiety. But for individuals who has high cortisol decline rate after acute stress, they recover fast to baseline after the stressor disappear, and they become less anxious although facing the same level of hindrance stressLimitations: Firstly, we only examined anxiety but left other distal outcomes of stress such as wellbeing to be further studied. Secondly, we choose the decline rate of cortisol to represent the HPA-axis function instead of taking different systems into consideration. Thirdly, stress appraisal could be further examined in the challenge-hindrance stress researches in addition to different stressors.Conclusions: The current study checked the association between stress and anxiety under the framework of challenge-hindrance stress. We examined the moderating mechanism of HPA-axis function, and discussed the effect of physiological toughness from the respective of resources and demands.
分类： 心理学 >> 应用心理学 提交时间： 2023-09-13
摘要： Background: While psychosocial stressors trigger neuroendocrine responses and affect task performance, many studies overlook the dynamic nature of the stress appraisal process. Goal: This study aims to explore whether subjective appraisals at various time points can interpret individual stress responses, both behaviorally and physiologically, using controlled laboratory conditions. Methods: A total of 137 effective participants were recruited to induce individual stress states using the Trier Social stress Test (TSST). Subjective appraisals were measured both before (anticipatory appraisal) and after the stressor (retrospective appraisal). Concurrently, participants' cortisol responses and task performances were documented. Results: Findings indicate that anticipatory appraisal doesn't significantly impact task performance, whereas retrospective appraisal markedly affects performance of the corresponding tasks. Regarding cortisol levels, multivariate regression analysis revealed that only the retrospective appraisal of the speech task accounted for the observed variance in cortisol response under stress. Discussion: The data suggests that retrospective appraisals are more indicative of behavioral and physiological responses to psychosocial stressors than anticipatory appraisals. These findings lend empirical support to refining the biopsychosocial model and underscore the utility of retrospective appraisal in capturing individual stress response variations.
分类： 生物学 >> 生物物理学 提交时间： 2016-05-12
Luo, Chuping
Guo, Junyao
Wang, Xiaoyu
Zhou, Huafei
Chen, Zhiyi
Luo, Chuping
Li, Xiangqian
Liu, Xuehui
Zhou, Xian
John Truong
摘要： Three families of Bacillus cyclic lipopeptides-surfactins, iturins, and fengycins-have well-recognized potential uses in biotechnology and biopharmaceutical applications. This study outlines the isolation and characterization of locillomycins, a novel family of cyclic lipopeptides produced by Bacillus subtilis 916. Elucidation of the locillomycin structure revealed several molecular features not observed in other Bacillus lipopeptides, including a unique nonapeptide sequence and macrocyclization. Locillomycins are active against bacteria and viruses. Biochemical analysis and gene deletion studies have supported the assignment of a 38-kb gene cluster as the locillomycin biosynthetic gene cluster. Interestingly, this gene cluster encodes 4 proteins (LocA, LocB, LocC, and LocD) that form a hexamodular nonribosomal peptide synthetase to biosynthesize cyclic nonapeptides. Genome analysis and the chemical structures of the end products indicated that the biosynthetic pathway exhibits two distinct features: (i) a nonlinear hexamodular assembly line, with three modules in the middle utilized twice and the first and last two modules used only once and (ii) several domains that are skipped or optionally selected.
点击量
待评议
点击量
下载量
评论
