Differential Effect of Two Mental Stress Tasks on Arterial Stiffness

Acute mental stress is believed to induce transient arterial dysfunction, but relatively few data are available. We therefore examined the effect of mental stress tasks that could induce differential hemodynamic responses on arterial dysfunction. Forty‐eight participants conducted either a mental arithmetic (MA) task or a mirror‐tracing (MT) task. Cardiovascular indices and arterial stiffness were measured before, during, and after these tasks. Analysis revealed that increases in arterial stiffness during the task and during recovery were more pronounced for the MA than for the MT, and that evoked hemodynamic response was more myocardial for MA than for MT. These results clearly show that MA and MT tasks that induce differential hemodynamic responses have a differential effect on arterial stiffness. This finding sheds light on the underlying mechanism that may account for the relationship between cardiovascular reactivity and cardiovascular disease.     

The paradox of happiness: Why are we not doing what we know makes us happy?

Achieving and maintaining happiness can be difficult, especially when people are not engaging in the activities they know facilitate it. ‘Flow’ activities require clear rules, challenge, a high investment of energy, and have been shown to promote long-term happiness better than low investment, passive activities. Do people know this? In two studies, we found that, despite recognizing that flow activities are more likely to facilitate happiness, people nevertheless participated in passive leisure significantly more often in a typical week. Participants rated passive activities as being significantly more enjoyable, requiring less effort, and being less daunting to get started than flow activities. Participants’ engagement in flow activities was significantly predicted by how enjoyable the activities were perceived to be, whereas how daunting those activities were rated predicted non-engagement. Passive activity engagement was only significantly predicted by enjoyment. Suggestions for enabling people to rise above the barriers to flow activities are offered.     

Blood pressure responses of defensive hostile women when facing a real stress task

Objective: This study investigated the importance of the combination of the hostility and defensiveness variables as psychosocial factors that predict the risk of cardiovascular dysfunction. We examined the impact of a stressful situation on blood pressure responses, using a continuous psychophysiological assessment approach.

Design: We measured the evolution of these responses over three experimental phases (adaptation, task and recovery), also considering a minute-by-minute analysis within each phase.

Main Outcome Measures: We used the Cook-Medley Hostility Scale and the Social Desirability Questionnaire to form four groups (high hostility and high defensiveness, high hostility and low defensiveness, low hostility and high defensiveness, and low hostility and low defensiveness).

Results: We expected the group of hostile defensive women to record higher activation (task phase: an academic exam) and slower habituation (recovery phase) compared to the other groups. The results confirmed our hypothesis, as the profile of the hostile defensive individuals was one of constant or sensitization during the task phase, while during the recovery phase those individuals underwent a slow recovery.

Conclusion: Therefore, it can be indicated that the low hostility and low defensive group is the most adaptive, as recorded very little activation in response, and rapid recovery.     

Preliminary evidence of attenuated blood pressure reactivity to acute stress in adults following a recent marital separation

Objective: This study explores cardiovascular reactivity during an acute-stress task in a sample of recently separated adults.

Design: In a cross-sectional design, we examined the association between adults’ subjective separation-related distress and changes in heart rate and blood pressure across the acute-stress laboratory paradigm in a sample of 133 (n = 49 men) recently separated adults.

Main outcome measures: Heart rate (HR) and Blood pressure (BP) were recorded across a resting baseline period, a math stressor task, and a recovery period.

Results: Multilevel analyses revealed that adults who reported greater separation-related distress exhibited higher initial BP and a slower linear increase in BP across the study period. In addition, adults reporting greater separation-related distress evidenced significantly slower declines in diastolic blood pressure (DBP) following the acute-stress task. HR reactivity was not moderated by separation-related distress.

Conclusions: In recently separated adults, preliminary evidence suggests that the context of the stressors may reveal differential patterns of problematic reactivity (exaggerated or blunted responding). Greater emotional intrusion and hyperactivity symptoms may index increased risk for blunted cardiovascular reactivity to general stressors. This pattern of reactivity is consistent with models of allostatic load that emphasise the deleterious effect of hyporesponsivity to environmental demands.     

Transcendental Phenomenology and the Way to Happiness: Husserl’s Reply to Csikszentmihalyi

It is an unprecedented task to interpret Husserl’s transcendental phenomenology as a fundamental philosophy of happiness. Although happiness has been discussed in many psychologies, Csikszentmihalyi’s positive psychology defines happiness as “flow”, a psychic state of ongoing immersion guided by intrinsic motivations and rewards. In this paper, I interpret our transcendental consciousness as a radical “flow” maker and claim that in our transcendental life, happiness is what we ourselves are. Then, I propose this not only as an appeal to a change of attitude (i.e. reduction) for happiness, but also as a deep hermeneutics of the mental skills and activity designs suggested by positive psychology. In this way, worldly happiness dictums can be profoundly re-examined. Understood as such, Husserl’s transcendental phenomenology leaves us the task of how to make a concrete form of qualitative or hermeneutical research on happiness out of it.     

The adaptive value of personality differences revealed by small island population dynamics

Whether differences in personality among populations really exist and, if so, whether they are only due to cultural and linguistic differences or have a genetically selected adaptive value, is a controversial issue. In this research, we compared three Italian populations living on three small archipelagos in the Tyrrhenian Sea (n = 993), with their corresponding neighbouring mainlanders (n = 598), i.e. sharing the same geographical origin, culture and language. We used an adjective‐based Big Five questionnaire in order to measure personality traits in four categories of individuals for each archipelago/mainland population: (1) original islanders; (2) non‐original islanders; (3) mainlanders and (4) immigrants to the islands. We further analysed original and non‐original islanders who had or had not emigrated from the islands. We found that islanders had different personality traits from mainlanders, the former being more conscientious and emotionally stable and less extraverted and open to experience. We also found that the subgroup of islanders whose ancestors had inhabited their island for about 20 generations in isolation (original islanders, n = 624) were less extraverted and open to experience than immigrants (n = 193). In contrast, immigrants retained the typical personality profile of the mainland populations. Lastly, emigrants from the islands (n = 209) were significantly more extraverted and open to experience than original and non‐original islanders who had never left their island (n = 741). We hypothesise that population differences in extraversion and openness to experience are more probably related to genetic differences which evolved rapidly, presumably through an active gene flow produced by selective emigration from the islands. Copyright © 2006 John Wiley & Sons, Ltd.     

血-前列腺屏障的假说及其对前列腺炎研究的意义

在慢性前列腺炎的研究工作中,血-前列腺屏障的研究是个被忽视的领域。在Pubmed等医学类数据库中找不到一篇关于血-前列腺屏障的研究综述。甚至找不到一个关于它的令人满意的定义。我们的研究目的,就是尝试从不同研究领域的文献中寻找有关“血-前列腺屏障”的理论和实验的依据,提出一个建立在非相关文献间的隐含联系中的假说。我们相信,血-前列腺屏障是客观存在的,而且在前列腺炎的发病机制中扮演着关键性的角色。     

一名宗教信仰者输血引发的思考

输血挽救了无数危重患者的生命,但少数宗教信仰者在自己或其家属急需输血时却拒绝输血治疗,而目前我国的法律法规在这一方面尚无明确规定,在此种情况下是否输血,医师处于两难的选择,也较易引起医患纠纷,为此建议我国卫生及其司法部门尽快制定相关法律法规,使医务工作者,在遇到此类问题时有章可循,有法可依。     

实验室检验失血与医源性贫血——ICU的潜在危机

所有的住院患者均需采血进行实验室检测,而ICU中的危重患者则更为频繁。有很多原因促使医生开立检验单,以明确疾病的诊断和治疗,但由此而产生的失血却往往易被忽视。病情的危重程度和器官功能障碍程度是检验失血量的主要影响因素,但同时采血技术、检验分析仪性能以及医生开立检验单的目标和规范性等欠佳会增加血液标本的浪费。积极地进行规范的医疗管理和实验室仪器设备的改进等,在满足患者病情治疗需要的前提下尽量降低检验性失血,需要全社会的努力。     

Security of multi-agent systems: A case study on comparison shopping

The multi-agent-systems paradigm is becoming more and more popular as a basis for realizing net-based solutions. This development is accompanied by an increasing relevance of security issues. For instance, the potential loss of privacy and other assets is a major concern for, both merchants and customers, in Internet-based commerce and, without being properly addressed, such very legitimate concerns hamper the growth of e-commerce.This article uses a comparison-shopping scenario to introduce a general methodology for formally verifying the security of multi-agent systems. Following the approach of possibilistic information flow security, the flow of information between and within agents is restricted in order to ensure that secrets will not be disclosed to unauthorized meddlers. The security requirements for the overall system are then decomposed into requirements for the individual agents that can be verified independently from each other. Exploiting the modular structure of a multi-agent system considerably reduces the complexity of the overall security analysis. The techniques for decomposing security requirements, for verifying individual agents, and for deriving global security guarantees for the entire system from locally verified properties are all generic in the sense that they apply also to many other systems and security requirements than the ones that appear in the example scenario.