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121.
The operating microscopes may be a significant cause of fatigue and discomfort in surgeons. The need for the microscope to be placed over the operating field forces surgeons to remain at the microscope's eyepieces at an uncomfortable posture for the entirety of the surgery. This study compared the effects on microsurgical task performance for four visualization methods: a monocular microscope, a binocular microscope, a three-dimensional (3D) flat-panel television display and a two-dimensional (2D) flat-panel television display. Eleven subjects each performed two microsurgical tasks and their performance was documented by video camera. The statistical analysis performed indicated utilization of the microscope as a visualization method increased subject performance. No significant difference in performance between the 2D and stereoscopic visualization methods.  相似文献   
122.
Cho YJ  Kim JY 《Work (Reading, Mass.)》2012,41(Z1):2545-2548
The aim of this study is to investigate the stationarity of the electromyographic (EMG) signals during isokinetic exertions of the trunk muscle. Six healthy subjects participated in this study. The erector spinae muscles were used to collect the signals. In order to simulate the isokinetic exercises of the trunk, a Cybex system with a trunk modular component was used. All subjects performed sustained exertions with a combination of load (25%, 50% MVC) and angular velocity (0, 15, 30 degree/s). The stationarity of the signals was tested by the reverse arrangements test and modified reverse arrangements test. In the results, the signal stationarity was high in all conditions in the reverse arrangements test. However, in the modified reverse arrangements test it was relatively low at about the 30 degree/s angular velocity. In the analysis of variance, the effect of angular velocity was statistically significant at the 0.05 significance level in the modified reverse arrangements test and Tukey's HSD grouping showed that the stationarity of 30 degree/s angular velocity was significantly different from 0, 15 degree/s condition. These results indicate that the stationarity of the EMG signals showed no difference between isometric and isokinetic conditions when the angular velocity was equal to 15 degree/s.  相似文献   
123.
Conventional advice is to reduce risky investments as one ages. Such a generalized focus on risk avoidance may be inappropriate for elderly with longer life spans and those with financial goals that extend beyond their lifetime. To better understand risky asset holdings among the elderly, we investigated the effect of cognitive ability and bequest motive on stock ownership and stock purchase. Using the 2004 wave of the Health and Retirement Study, we found that one-third of elderly households held stocks and 36% of those elderly stockowners had recently acquired stocks. The respondent??s cognitive ability and bequest motive were strongly related to stock ownership. Among those who owned stock, a bequest motive was positively related to a recent purchase of stocks.  相似文献   
124.
In this study the authors assessed the effects of disability beliefs, conceptualization and labeling of emotional disabilities, and perceived barriers on help-seeking behaviors among depressed Chinese Americans in a primary care setting. Forty-two Chinese Americans participated in semistructured interviews using established psychological measures and open-ended questions adapted from the Explanatory Model Interview Catalogue. The authors found that care utilization appears to be complicated by somatization of emotional problems, variations in causal attribution to depression, barriers to receiving mental health care, and the burden of comorbid physical conditions. Their findings highlight the importance of addressing these issues and educating patients about body-mind dialectic common to depression.  相似文献   
125.
Studies indicate positive effects of the U.S. Vocational Rehabilitation Services (VRS) in assisting people with disabilities to find independent employment. Underemployment continues to impact access to adequate health care and other benefits. Workers with disabilities receive fewer benefits, overall. With data from the Longitudinal Study of Vocational Rehabilitation Services Program (LSVRSP), the authors compare the rates of receipt of 6 types of benefits for people with physical, mental, and sensory impairments. Although those with physical disabilities are most likely to receive benefits, all groups lack adequate access to health care, sick leave, and vacation. The authors discuss implications for services provision in the current job market.  相似文献   
126.
Increases in hours of work per capita over past 30?years have created an intuitively plausible notion that there now is less time for social interaction. The purpose of this paper is to empirically investigate the effect of hours of work on social interaction. The empirical work is complicated by the argument that unobserved factors could increase both hours of work and social interaction. The empirical work in this paper employs an exogenous decline in hours of work in France due to a new employment law to bypass this endogeneity problem. The data employed are derived from the 1999?C2003 Continuous Survey of Household Living Conditions which is a random sample of French households. Gender specific results from a difference-in-difference model show that the employment laws reduced hours of work but there is no evidence that the extra hours went to increased social interactions. Contrary to the intuitive argument, the paper concludes that in the range of approximately 94 extra hours of leisure per year, hours of work have no effect on social interaction.  相似文献   
127.
Research on predictors of treatment outcome among pathological gamblers (PGs) is inconclusive and dominated by studies from Western countries. Using a prospective longitudinal design, the current study examined demographic, clinical, behavioural and treatment programme predictors of gambling frequency at 3, 6 and 12-months, among PGs treated at an addiction clinic in Singapore. Measures included the Hospital anxiety and depression scale, gambling symptom assessment scale (GSAS), personal well-being index (PWI), treatment perception questionnaire and gambling readiness to change scale. Treatment response in relation to changes in symptom severity, personal wellbeing and abstinence were also assessed. Abstinence rates were 38.6, 46.0 and 44.4 % at 3, 6 and 12-months respectively. Significant reductions in gambling frequency, GSAS, and improvement in PWI were reported between baseline and subsequent outcome assessments, with the greatest change occurring in the initial three months. No demographic, clinical, behavioural or treatment programme variable consistently predicted outcome at all three assessments, though treatment satisfaction was the most frequent significant predictor. However, being unemployed, having larger than average debts, poor treatment satisfaction and attending fewer sessions at the later stages of treatment were associated with significantly poorer outcomes, up to 1-year after initiating treatment. These findings show promise for the effectiveness of a CBT-based treatment approach for the treatment of predominantly Chinese PGs. Clinical implications and suggestions for future research are discussed. Taken together, the findings suggest early treatment satisfaction is paramount in improving short-term outcomes, with baseline gambling behaviour and treatment intensity playing a more significant role in the longer term.  相似文献   
128.
Previous studies find that some social groups are stuck in poverty traps because of network effects. However, these studies do not carefully analyze how these groups overcome low human capital investment activities. Unlike previous studies, the model in this paper includes network externalities in both the human capital investment stage and the subsequent career stages. This implies that not only the current network quality, but also the expectations about future network quality affect the current investment decision. Consequently, the coordinated expectation among the group members can play a crucial role in the determination of the final state. We define “overlap” for some initial skill ranges, whereby the economic performance of a group can be improved simply by increasing expectations of a brighter future. We also define “poverty trap” for some ranges, wherein a disadvantaged group is constrained by its history, and we explore the egalitarian policies to mobilize the group out of the trap.  相似文献   
129.
Although the government no longer explicitly establishes boundaries of whiteness, it continues to play a central role in shaping symbolic boundaries between immigrants and nonimmigrants through immigration lawmaking. However, the salience of these boundaries may depend on how the media disseminate them to the public. In this study, we investigate media framing of immigration lawmaking using an original data set of news coverage of six of the most widely recognized exclusionary immigration bills and laws at different levels of government. Two patterns emerged from an iterative frame analysis. First, in their coverage of frames critical of these bills and laws, outlets devoted more attention to the effects of exclusionary legislation for nonimmigrants. Second, in their coverage of frames supportive of the restrictive legislation, outlets provided more space to those who openly associated immigrants with criminality and terrorism. Regardless of outlets’ seemingly neutral stance toward restrictive legislation, their disparate coverage of exclusionary lawmaking demonstrates apathy and antipathy toward immigrants, which has repercussions for the maintenance of inequality.  相似文献   
130.
The Registers of Liberated Africans that were compiled in the course of British anti-slave trade suppression contain detailed biographical information for individuals who were liberated from slave ships according to international law. These records are invaluable for an analysis of the demography of the trans-Atlantic slave trade, and hence it is necessary to assess critically their generation, including who made them and for what reasons. By focusing on the Havana Slave Trade Commission between 1824 and 1841, this essay provides an overview of the registration process of over 10,000 Africans, the structure of the Mixed Commission court, and details on the court officials, including a list of 162 African-born interpreters that resulted in the issuance of emancipation certificates to thousands of Liberated Africans who were subsequently subjected to terms of apprenticeship negotiated by the British and Spanish governments.  相似文献   
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