Toward an understanding of aging in plutonium from direct measurements of stored energy

ABSTRACT

We present here the first direct measurement of the radiation-damage-induced energy stored in δ-phase plutonium. The primary mode of radioactive decay of ²³⁹Pu occurs with a time constant of τ=1.1?×?10¹²?s. Each decay imparts about 85?keV of recoil energy to the uranium byproduct, 5.2?Mev to the alpha particle, and a spectrum of mostly low energy gamma rays with the most probable at 51?keV [1]. Most of the decay energy is converted immediately to heat, releasing about 1.9?mW/g. However, some thermally-recoverable energy remains trapped. Reported here are measurements of that stored energy using differential scanning calorimetry (DSC) applied to ²³⁹Pu-2.0 at.%Ga δ-phase alloy. Retained energy of ～2 J/g saturates at about 5 months and is unchanged after 30 years. The magnitude of the stored energy agrees with a short-bond defect model that that we present here. This model treats radiation damage as a Pu impurity with shortened bond lengths. It explains the change in known properties with age and predicts that density increases with age, contrary to current thinking. The short-bond impurities proposed are expected to act like other impurities, affecting strength, phase transitions, grain boundaries and other metallurgical properties.     

Crystal growth and defect study of BiSbTe3

BiSbTe₃ single crystals have been grown by the Bridgman technique. Microscopic observations of the as-grown crystals reveal typical features, such as striations on the top free surface, which are attributed to the effect of growth conditions. A nitric-acid-based reagent capable of revealing dislocations has been developed and tested. Etch pits are produced at the dislocation sites, but some discrepancies have been observed on matched cleavage surfaces. The structural difference between the matched cleavage surfaces is discussed.     

用于企业人事管理的《企业管理能力倾向测验》

《企业管理能力倾向测验》（简称ＭＡＴ）的开发满足了企业改革的需要,企业管理职业能力倾向被界定为一种介乎于一般智力和具体的知识,技能之间的心理特点,ＭＡＴ主要考究受测者与做好企业管理工作有关的那些影响较广,比较稳定,潜在的,不易受到环境影响的能力,ＭＡＴ包括言语理解,数量关系,逻辑推理,资料分析和思维策略等５个部分,ＭＡＴ经过两次预测和课目筛选,常模样本包括２６个省市的１４９家企业２８１４名中层以上     

Understanding Transference and Countertransference

Abstract

Professional misconduct-especially misconduct involving client-worker boundary violationsgenerates serious costs for clinical social workers. It harms the very clients we aim to help; it frequently tarnishes the reputation of not only the individual social worker involved but also the face of the entire profession; and, it adds significantly to the overall costs of malpractice insurance. This paper defines the scope of the problem and provides support for understanding transference and countertransference as important contributors to prevention.     

Re-Examination of Classroom Rules

Abstract

This article provides a contemplative, research-based discussion of classroom management by examining classroom rules. The introduction contains a discussion establishing the importance of effective classroom management strategies. The article also provides a consideration of the literature to gain a better understanding of ineffective and effective rules.     

School-Wide Discipline and Classroom Ecology

Abstract

Shortages of teachers with specialized skills, coupled with increased difficulty accommodating students with problem behaviors in general education classrooms, create pressures for performance and accountability in schools and with respect to teachers. Matters become increasingly problematic by initiatives that stress high academic competence, high graduation rates, and high performance standards. In addition, heightened cultural and linguistic diversity, diminished public satisfaction, and increased violence and disruptive behavior at school levels suggest a need for effective, easy-to-implement discipline procedures. In this investigation, we describe improvements in classroom ecology after implementation of a school-wide discipline model. These outcomes were positive and provide support for continuing efforts to improve discipline within the schools.     

Organizational factors and mental health in community volunteers. The role of exposure,preparation, training,tasks assigned,and support

During disasters, aid organizations often respond using the resources of local volunteer members from the affected population who are not only inexperienced, but who additionally take on some of the more psychologically and physically difficult tasks in order to provide support for their community. Although not much empirical evidence exists to justify the claim, it is thought that preparation, training, and organizational support limit (or reduce) a volunteer's risk of developing later psychopathology. In this study, we examined the effects of preparation, training, and organizational support and assigned tasks on the mental health of 506 Indonesian Red Cross volunteers who participated in the response to a massive earthquake in Yogyakarta, Indonesia, in 2006. Controlling for exposure level, the volunteers were assessed for post-traumatic stress disorder (PTSD), anxiety, depression, and subjective health complaints (SHCs) 6, 12, and 18 months post-disaster. Results showed high levels of PTSD and SHCs up to 18 months post-disaster, while anxiety and depression levels remained in the normal range. Higher levels of exposure as well as certain tasks (e.g., provision of psychosocial support to beneficiaries, handling administration, or handing out food aid) made the volunteers more vulnerable. Sense of safety, expressed general need for support at 6 months, and a lack of perceived support from team leaders and the organization were also related to greater psychopathology at 18 months. The results highlight the importance of studying organizational factors. By incorporating these results into future volunteer management programs the negative effects of disaster work on volunteers can be ameliorated.     

Randomized controlled trial evaluating the effectiveness of a web-based stress management program among community college students

Background and Objectives: This study evaluated the effectiveness of a web-based stress management program among community college students that focused on increasing perceived control over stressful events. Design: Students (N = 257) were randomly assigned to a Present Control Intervention or a Stress-information only comparison group. Methods: Primary outcomes were perceived stress and stress symptoms; secondary outcomes were depression and anxiety. Self-report measures were completed online at preintervention, postintervention, and three-week follow-up. Intervention effects were estimated using linear mixed models. Seventy-five percent of the sample (n = 194) completed the pretest and comprised the intent-to-treat sample. Results: Participants in the intervention group reported significant increases in present control, and significant decreases in all four primary and secondary outcome measures from baseline to postintervention and follow-up. Within-group effect sizes were small to medium at postintervention (mean d = –.34) and follow-up (mean d = –.49). The mean between-group effect size on the four outcome measures was d = .35 at postintervention but d = .12 at follow-up, due to unexpected decreases in distress in the comparison group. Conclusions: Our online program is a cost-effective mental health program for college students. Limitations and future direction are discussed.     

The paradox of power sharing: Participative charismatic leaders have subordinates with more instead of less need for leadership

Although charismatic and participative leaders have been noted for their positive effects on criteria such as performance, job satisfaction, and commitment, few studies have looked at the relations with subordinates' leadership needs. In this study, the relations between charismatic and participative leadership, team outcomes, and a team's need for leadership were investigated. The sample consisted of South Pacific CEOs and their top-level management teams from Fiji, Tonga, Samoa, Vanuatu, and the Solomon Islands. Results showed that charismatic leadership was related to both group-level need for leadership and positive team outcomes. However, team outcomes did not mediate the relations between leadership and a team's need for leadership. Additionally, a moderator effect was found between participative leadership and charismatic leadership in explaining a team's need for leadership, implying that teams of subordinates with participative charismatic leaders need more instead of less leadership from their CEOs.     

The moderator role of followers’ personality traits in the relations between leadership styles,two types of task performance and work result satisfaction

Authentic leadership is changing our understanding of what makes good leadership. However, few studies have explored how followers’ individual differences and the nature of the task they perform affect its relation to followers’ work outcomes. We examine the moderator role of two core task types (intellective vs. generative) and two personality traits (conscientiousness and emotional stability) in the relationship between two leadership feedback styles (authentic vs. transactional) and task performance or work result satisfaction in a two-wave experiment. The sample consisted of 228 participants enrolled in an organizational psychology course, 34% of whom had work experience. Our results show that over time the effect of an authentic feedback style on task performance became stronger for those participants who previously scored very low on intellective tasks or very high on generative tasks. Furthermore, a significant three-way interaction between these two traits and our leadership feedback styles indicates that the effect of authentic feedback conforms different patterns depending on the followers’ personality traits and the type of task they perform. Moreover, authentic feedback had a stronger effect on participants’ work result satisfaction. Participants with low levels of either conscientiousness or emotional stability displayed higher levels of satisfaction in the authentic feedback condition.