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281.
The Y2K Bug, the programming glitch expected to derail computerized systems worldwide when the year changed from 1999 to 2000, provided a rich context for examining anticipatory coping and preparatory behaviors. In the last 2 months of 1999, 697 respondents completed an online survey of proactivity, worry about Y2K, dispositional optimism, primary and secondary control-oriented coping efforts, estimates of Y2K-related disruptions, and household preparations. Higher levels of proactivity, worry, and optimism were independently associated with greater self-reported preparations. These predictors were positively associated with greater primary control-oriented coping efforts, but showed differential relations to secondary control efforts, such as accepting the situation or trusting a higher power, especially among participants who thought the damage would be severe and lasting. Implications for understanding multiple ways of coping with potential stressors are discussed.
Lisa G. AspinwallEmail:
  相似文献   
282.
Frontal lobe patients reproduced a sequence of capital letters or abstract shapes. Immediate and delayed reproduction trials allowed the analysis of short- and long-term memory for time order by means of suitable Markov chain stochastic models. Patients were as proficient as healthy subjects on the immediate reproduction trial, thus showing spared encoding and short-term memory. They failed, instead, on the delayed trials with capital letters, but not with random shapes, suggesting that their long-term memory impairment did not depend on primary deficits for ordering, but on inability to benefit from the organisational strategies that improve the retention and retrieval in normal subjects.  相似文献   
283.
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.  相似文献   
284.
He and H can be produced by nuclear reaction. In addition, energetic particles of He and T and D, which are isotopes of H, in the plasma of fusion reactor induce the damage in the surface of materials, such as erosion, sputtering and blistering. To investigate the interaction of He and D, amorphous and crystalline FeBSi alloys were irradiated by He or D2 or He?+?D2 ions with 5?keV. The results of thermal desorption indicated that more He atoms were trapped in both the amorphous and crystalline alloy irradiated by He ions than D atoms in those alloys irradiated by D2 ions. Although He and D atoms were trapped in FeBSi alloy irradiated by He?+?D2 ions, desorption peaks of D2 and He were separated. Absorption of D in an amorphous alloy was influenced by the presence of He; however, absorption of He was independent of D2 irradiation in both alloys.  相似文献   
285.
采用事件相关电位(ERPs)技术探索延迟匹配任务范式下面孔识别工作记忆的脑电位特征。实验以面孔图片为刺激,在校大学生被试完成靶匹配工作记忆任务。结果发现,被试识别靶面孔及分心物面孔时均在枕颞区两侧诱发N170,且靶与分心物的N170振幅在相同电极上都没有显著差异,在颞区两侧的P7和P8上差异显著;无论靶面孔还是分心物面孔,工作记忆的 ERPs均产生了 P300成分。在分别追踪新靶和熟悉靶的工作记忆任务条件下,靶与分心物的ERPs波形在250 ms后出现分离,且靶刺激波幅均比分心物更正,新靶比熟悉靶更正。熟悉分心物与新分心物之间显示出250~650 ms的前额区旧/新效应,在晚期的450~650 ms时段,新工作记忆比旧工作记忆波幅更正。这些结果表明,面孔识别的N170效应可能反映的是面孔知觉的整体加工,且 N170的右半球优势具体为颞区的右侧优势;先前的面孔学习会影响工作记忆期间大脑对面孔的识别反应。  相似文献   
286.
基于捐献行为的公益性、单务性和人身性,各国法律赋予捐献人任意撤销权,但是出于对捐献人允诺的信赖而改变自身处境的接受人利益也应该得到保护.从信赖保护的视角出发,在血型高分辨检测之前,捐献人一旦签订了捐献协议,即负有保护接受人信赖利益的义务,捐献人虽然有权中途拒捐,但应当承担信赖赔偿责任.  相似文献   
287.
采用掩蔽启动范式考察了负相容效应中启动项与目标项关系对阈下信息加工的影响,以及是否存在语义水平的负相容效应.两个实验分别以双箭头和汉字为掩蔽启动项,考察启动项和目标项重复、加工水平相同及加工水平不同三种条件下的启动效应.结果发现,两个实验的重复及加工水平相同条件下都出现负相容效应,且重复条件下启动量最大,加工水平不同条件下则无启动.这表明:(1)启动项与目标项的知觉重复影响启动量,但不是负相容效应的必要条件,只有当启动项和目标项加工水平相同时,才出现负相容效应;(2)存在语义水平上的负相容效应,阈下语义信息可得到加工并表现为对后继同类反应的抑制.  相似文献   
288.
Abstract

Research has shown that lymphocytes of high-distress patients have reduced DNA repair relative to that of low-distress patients and healthy controls. Furthermore, deficits in repair are associated with an increased risk of cancer. Using and academic stress model, we hypothesized that students would exhibit lower levels of Nucleotide Excision Repair (NER) during a stressful exam period when compared to a lower stress period. Participants were 19 healthy graduate level students. NER was measured in lymphocytes using the unscheduled DNA synthesis (UDS) assay with slide autoradiography. Contrary to prediction, mean values for NER significantly increased during the higher stress period relative to the lower stress period controlling for background differences in repair. Furthermore, lymphocytes had significantly increased repair of endogenous damage during the higher stress period. Stress appears to directly increase DNA repair. Additionally, stress may increase DNA repair indirectly by increasing damage to DNA.  相似文献   
289.
针对一些进展期胃癌患者,胃癌联合脏器切除术不仅可以缓解症状,改善生活质量,甚至有的病例可以达到根治而长期存活。但是胃癌联合脏器切除术难度大,手术死亡率高,并发症多,故胃癌联合脏器术前应恰当地掌握手术指征,充分进行术前准备,正确判断可切除性,充分与患者沟通后周密设计手术方案,术中应进行细致有序的操作,术后应注意及时发现并...  相似文献   
290.
本研究初步考察目标刺激的熟悉度和呈现角度对情绪启动的影响。研究采用女性面孔图片作为实验材料,随机选取30名大学生被试进行实验,采用重复测量方差分析对数据进行统计分析。结果发现:当目标刺激为熟悉图片时,出现了情绪启动效应;当目标刺激为不熟悉的图片时,未发现情绪启动效应;目标刺激的呈现角度对情绪启动效应没有影响。  相似文献   
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