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101.
The purpose of this study was to examine individual and team performance in situations requiring sustained attention. Eighty research participants arrayed in 20 four-person teams worked for 2 separate 3-hr sessions on a naval-command-and-control simulation. The results of the study replicated the past literature on the vigilance decrement and extended the literature by documenting a postcritical signal decrement as well. The study also showed that problems in the area of sustained attention generalize from situations involving individual decision makers to contexts where decisions are made by teams. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
A S. mansoni adult worm cDNA expression library was screened with sera from baboons in a early phase after infection. The clones that were positive with the early infection sera were examined for reactivity with pre-infection sera and heterologous infection sera. In order to discriminate a positive antibody reaction from the reactivity due to residual anti-E. coli antibodies, an unrelated cDNA clone was plated with the positive clone. The unrelated clone provided the negative background and the contrast necessary to discern a positive antibody reaction. In this way, we were able to eliminate selected clones that were positive with the pre-infection sera or heterologous infection sera. This characterization of the expression library clones enabled us to quickly target only clones with the desired pattern of antibody reactivity for sequencing, subcloning, and expressing.  相似文献   
103.
OBJECTIVE: The purpose of the study is to evaluate the monocular and binocular outcome of three types of "penalization" (blurring of the sound eye) treatment of amblyopia: traditional full-time atropine or optical penalization and a new intermittent atropine regimen involving atropine instillation 1 to 3 days a week. DESIGN: The study design was a retrospective study. PARTICIPANTS: A total of 163 patients with strabismic amblyopia treated by full-time atropine (n = 38), intermittent atropine (n = 73), or optical (n = 52) penalization participated. MAIN OUTCOME MEASURES: Logarithm of the minimum angle of resolution (logMAR) visual acuity, and binocularity index were determined. RESULTS: All three forms of penalization produced statistically significant mean reduction in amblyopia (1.7-2.7 logMAR lines) and mean improvement in binocularity by the end-of-treatment or long-term follow-up visit or both, with minimal mean loss after discontinuation or slight mean improvement on these measures at long-term mean follow-up of 1.9 to 4 years across groups. Few patients achieved high-grade stereoacuity. Compliance was high. Comparable efficacy was found for all three treatment groups after controlling for age, depth of amblyopia, and binocularity at the initial visit. Initial-visit amblyopia depth was strongly and significantly associated with amblyopia depth at both post-treatment visits. Pretreatment and post-treatment binocularity showed a similar strong relationship. Surprisingly, however, there was no consistent or significant association found between depth of amblyopia and binocularity in any visit combination. Post-treatment measures of these two variables also were not associated with initial-visit age or refractive error at any clinically significant level. Mean treatment duration was 1.1 to 2.9 years and was not found to be associated with visual outcome. Amblyopia reversal was found in one (full-time atropine) case at a clinically important level. CONCLUSIONS: The authors confirmed previous reports of penalization's efficacy as a primary treatment of moderate amblyopia (20/100 or better acuity) and, in some cases, relatively severe amblyopia (>20/100) and also confirmed its ability to significantly improve mean binocularity. Amblyopia and binocularity appear to respond to treatment independently and, within the postinfancy age range of the sample studied, the responses appear to be independent of initial-visit age. The high acceptability to patients and parents of atropine penalization, and particularly of the intermittent regimen introduced here, suggests the need for prospective-study-based re-evaluation of the relative merits of penalization and occlusion as the standard of care for mild-to-moderate amblyopia.  相似文献   
104.
The impression of series resistance on unipolar semiconductor device’s capacitance–voltage spectrum is discussed by conventional impedance and admittance analysis, and it is shown that series resistance may cause large errors in capacitance–voltage data. It is shown that the existence of such errors can be deduced from suitable complex impedance measurement obtained during the capacitance–voltage measurement process and this information can be used to correct the distorted capacitance values. A theoretical analysis and computer simulation are presented in order to illustrate the nature of the problem and the technique by which accurate depletion region capacitance can be obtained.  相似文献   
105.
61 children were studied and treated between January 1986 and September 1993 for idiopathic varicocele. The aim of our study was to evaluate the advantages and disadvantages of the different techniques and to show the progression to a greater efficacy. The mean age at the time of therapy was 14 years, ranging from 7 to 16 years. All children presenting with pain or testicular asymmetry were treated. Four asymptomatic children were followed for 2 years before treatment. 36 children were treated by surgical ligature via the inguinal approach; 8 with a resection of the varicose veins as far as the tunica vaginalis. 14 children were treated by percutaneous sclerotherapy including 1 patient following unsuccessful classical surgical treatment. 12 children were treated by surgical inguinal ligature associated with peroperative phlebography and thrombosis. 56 children were reviewed postoperatively over a period which varied from 2 months to 4 years (5 lost to follow-up). For the 36 classical ligatures: 25 good results, but 9 hydroceles (5 out 8 varicose resections): 70% good results. 7 failures and 4 lost to follow-up. For the 14 percutaneous sclerotherapy: 4 technical failures (impossibility to catheterize the spermatic vein): 10 good results. For the 12 ligatures with peroperative phlebography and thrombosis: 11 good results and 1 lost to follow-up. All the above procedures were carried out at our out-patient clinic. The therapeutic choice will therefore have to take into consideration a procedure which produces the lowest morbidity rate and proves to be the most effective. The association of surgical ligature, phlebography and thrombosis meets these requirements.  相似文献   
106.
G. P. Latham and E. D. Pursell (see record 1975-24318-001) suggested that the traditional focus on absenteeism may have been misguided. They argued that absenteeism is not a behavior but rather the absence of behavior; therefore, it would be better to be concerned with attendance rather than absenteeism. They presented data purported to demonstrate that attendance is a more reliable measure than absenteeism as well as more appealing theoretically. It is concluded in the present paper that attendance measures have few theoretical advantages over absenteeism measures and that the differences in reliability are limited. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
Examined the relationship of stressful life events in and out of work to role-relevant information search. It was suggested that stressful life events lead a person to question the appropriateness of typical modes of role enactment resulting in increased role-relevant information search. 44 adults (mean age 37.7 yrs) employed in a wide variety of organizations completed the Social Readjustment Rating Scale and the Organizational Readjustment Rating Scale that measure 2 types of stressful events (life and work), and role-related information search was assessed in 2 settings (on and off the job). Results show that stressful events significantly predicted information search activities. However, work-related stressful events predicted information search conducted on the job, whereas life stress predicted off-the-job search. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
108.
The preferences of men and women for working alone or with others were examined. 150 undergraduates were presented with masculine and feminine tasks and were offered the choice of working alone or with others on the tasks. A cognitive model predicted that the congruence between gender and the sex-type of the task would affect expectancies of success, which, in turn would affect choice. From an individual difference perspective, it was predicted that interpersonal orientation would affect choice. The cognitive perspective model was supported, whereas interpersonal orientation had little effect on choice. The results were discussed in terms of their implications for task perceptions and gender differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
Industrial robots, which enable manufacturing firms to produce high-quality products in a cost-effective manner, are important components of advanced manufacturing technologies. The performance of industrial robots is determined by multiple and conflicting criteria that have to be simultaneously considered in a robust selection study. In this study, a decision model based on fuzzy linear regression is presented for industrial robot selection. Fuzzy linear regression provides an alternative approach to statistical regression for modelling situations where the relationships are vague or the data set cannot satisfy the assumptions of statistical regression. The results obtained by employing fuzzy linear regression are compared with those of earlier studies applying different analytical methods to a previously reported robot selection problem.  相似文献   
110.
The use of blood for normothermic and subnormothermic kidney preservation hinders the translation of these approaches and promising therapeutics. This study evaluates whether adding hydrogen sulfide donor AP39 to Hemopure, a blood substitute, during subnormothermic perfusion improves kidney outcomes. After 30 min of renal pedicle clamping, porcine kidneys were treated to 4 h of static cold storage (SCS-4 °C) or subnormothermic perfusion at 21 °C with Hemopure (H-21 °C), Hemopure + 200 nM AP39 (H200nM-21 °C) or Hemopure + 1 µM AP39 (H1µM-21 °C). Then, kidneys were reperfused with Hemopure at 37 °C for 4 h with metabolic support. Perfusate composition, tissue oxygenation, urinalysis and histopathology were analyzed. During preservation, the H200nM-21 °C group exhibited significantly higher urine output than the other groups and significantly higher tissue oxygenation than the H1µM-21 °C group at 1 h and 2h. During reperfusion, the H200nM-21 °C group exhibited significantly higher urine output and lower urine protein than the other groups. Additionally, the H200nM-21 °C group exhibited higher perfusate pO2 levels than the other groups and significantly lower apoptotic injury than the H-21 °C and the H1µM-21 °C groups. Thus, subnormothermic perfusion at 21 °C with Hemopure + 200 nM AP39 improves renal outcomes. Additionally, our novel blood-free model of ex vivo kidney preservation and reperfusion could be useful for studying other therapeutics.  相似文献   
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