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21.
Earth''s known supercontinents are believed to have formed in vastly different ways, with two endmembers being introversion and extroversion. The former involves the closure of the internal oceans formed during the break-up of the previous supercontinent, whereas the latter involves the closure of the previous external superocean. However, it is unclear what caused such diverging behavior of supercontinent cycles that involved first-order interaction between subducting tectonic plates and the mantle. Here we address this question through 4D geodynamic modeling using realistic tectonic set-ups. Our results show that the strength of the oceanic lithosphere plays a critical role in determining the assembly path of a supercontinent. We found that high oceanic lithospheric strength leads to introversion assembly, whereas lower strength leads to extroversion assembly. A theoretically estimated reduction in oceanic crustal thickness, and thus its strength, during Earth''s secular cooling indicates that introversion was only possible for the Precambrian time when the oceanic lithosphere was stronger, thus predicting the assembling of the next supercontinent Amasia through the closure of the Pacific Ocean instead of the Indian-Atlantic oceans. Our work provides a new understanding of the secular evolution of plate tectonics and geodynamics as the Earth cooled.  相似文献   
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目前工程中常见的通病——现浇砼楼面、墙体、阳台隔墙裂缝越来越被人们普遍关注,虽然其对结构安全一般不构成威胁。但对工程的耐久性与美观仍构成一定的影响,同时也给缺乏专业知识的住户带来不安全感,并由此引起了诸多纠纷。在此,本文分析了现浇砼楼面、墙体、阳台隔墙裂缝产生的原因,并着重从材料、施工工艺、设计等方面提出了一些具体的预防措施和控制措施。  相似文献   
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The authors examined the relationship between stress, adaptive coping, and life satisfaction among college students who reported having a friend or family member with eating disorder symptomatology. A hierarchical regression confirmed the study's hypotheses. Higher stress was linked with less life satisfaction. After stress was controlled, plan coping had a beneficial influence on life satisfaction. College counselors can use these findings when choosing interventions for clients who are close to someone with an eating disorder.  相似文献   
25.
BackgroundCompassion fatigue (i.e., a worker’s diminished ability to empathize with clients) is common among “helping workers” and can result in psychological detachment from clients as a coping mechanism.ObjectiveIn the present research, we explored the relationship between social workers’ compassion fatigue and years of job experience on hypothetical child custody case judgments.Participants and settingIn two separate studies, individuals with experience working with children in child dependency court (predominantly social workers, Study 1: N = 173, Study 2: N = 119) were recruited on Amazon’s Mechanical Turk and read a vignette depicting a mother attempting to regain custody.ResultsSupporting hypotheses, compassion fatigue significantly mediated the relationship between increased years of social worker job experience on recommendations that a neglectful mother receive custody, Indirect Effect = .06, CIs [.026, .127] (Study 1). We also found preliminary support for our hypothesized theoretically derived serial path model, in which (a) social worker compassion fatigue predicts anticipated secondary traumatic stress associated with the child neglect case, B = .54, p = .0001; (b) secondary traumatic stress predicts detachment from the neglected child, B = .27, p = .0003; (c) detachment from the child predicts job efficacy cynicism B = .65, p < .0001; and (d) job efficacy cynicism predicts decisions to allocate custody to the neglectful mother, B = .46, p = .005 (Study 2).ConclusionOur research shows that compassion fatigue among social workers may change the lens through which they perceive cases of child abuse.  相似文献   
26.
Emerging fathers experience a variety of stressors, including identity and role transitions, changes in their relationships, and challenges in developing caregiving skills. Increasing expectations for father involvement in childcare are emphasizing the importance of the father role, but social supports for new fathers remain scarce. Nineteen expectant and new fathers participated in a pilot 5-week group intervention aimed at improving stress coping and involvement attitudes using a combination of mindfulness practices and skill-building for parenting and partner communication. We administered surveys pre- and postintervention to assess efficacy in the areas of stress, depressive symptoms, father involvement attitudes, and mindfulness. Within-participant differences were compared across participants as well as examining individual reliable change. Results indicated initial reductions in stress and depressive symptoms and increases in the mindfulness constructs of nonjudgment and nonreactivity. No significant changes were found in father involvement attitudes. Perinatal intervention specific to fathers holds promise as an underexplored avenue for supporting families across the transition to parenthood.  相似文献   
27.
大尺寸薄壁钢筋混凝土结构,对温度的变化和基础的不均匀沉降较为敏感。制定合理的施工方案,材料的合理选择、施工流程精心组织保证了裂缝控制效果良好。  相似文献   
28.
采用自编的心理冲突调查问卷、Cawte量表和主观幸福感指数量表(WBIS),调查531名大学生的心理冲突状况、应激水平及主观幸福感。结果为:(1)过多的心理冲突可引起生理与心理应激水平的升高;(2)心理冲突频率与应激水平呈显著的正相关(r=0.533,P<0.01);(3)心理冲突频率与主观幸福感呈显著的负相关(r=-0.158,P<0.01)。因此,过多的心理冲突已构成应激源,是影响学生身心健康的重要因素之一。大学生心理冲突问题应予以关注。  相似文献   
29.
This study examined how communal coping reveals itself in Palestinian refugee camps and the conditions that promote or prevent its occurrence. Individual and dyadic interviews were conducted with 40 mothers and one of their adolescent children living in Palestinian refugee camps in Lebanon. The results revealed that communal coping existed within the mother–adolescent dyad to a certain extent, but was rare within the larger context of the refugee camps. While families and neighbors did not typically verbalize their hardships and actively cope with them as a group, there was often an implicit recognition that they were all experiencing the same uncertainty and stress. Acting upon their uncertainty as a collective, however, was greatly hampered by mistrust within and outside the camps, due to widespread violence, privacy violations, vying for scarce resources, and disloyalty. Parents and adolescents also engaged in protective buffering whereby they attempted to reduce the stress of the family by keeping stress and fears to themselves rather than communicating about them. Even though protective buffering helped the refugees cope with chronic uncertainty and maintain a sense of normalcy, it prevented them from acting upon the problem as a group. Finally, parents emphasized that the child’s education provided hope for the future. Practical implications are discussed.  相似文献   
30.
建立一个安全的校园网访问控制体系   总被引:1,自引:0,他引:1  
校园网在运行过程中面临各种安全威胁,本论文通过对校园网及其应用系统的访问控制体系问题进行分析,就身份认证、防火墙、文件和服务的共享访问以及封锁系统漏洞四个方面提出基于访问控制的安全策略。  相似文献   
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