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11.
A literature search was conducted on studies of new drugs used with patients with schizophrenia reported by U.S. and non-U.S. researchers from 1966–1993, yielding 41 U.S., and a total of 24 other non-U.S. studies, among them 11 British studies. Results of the U.S. and non-U.S. studies were pooled separately and compared. Among several comparable conditions discussed, the lack of any data on suicides in the U.S. studies was observed. For a second statistical analysis of suicide rates ‘person-years’ were calculated to adjust for differing washout durations. The results obtained include findings that the percentage of patients relapsing in U.S. studies was slightly lower (37.9%) than in non-U.S. studies (46%); the percentage of patients dropping out in U.S. studies (10.5%) was higher than in non-U.S. studies (7.6%); known location of dropout patients in U.S. studies was 1.7%, compared to 2.6% in non-U.S. studies. The most interesting finding was that no suicides were reported in U.S. studies, compared to 0.6% of patients reported in British studies. Some U.S. studies used ‘challenge doses’, such as amphetamines or L-dopa; no non-U.S. studies reported their use. Compared to U.S. studies, those by non-U.S., and particularly British, researchers appeared to report adverse events in their studies. ‘Challenge’ drugs were not used; suicides were reported. It is estimated that the probability that no patients suicided who participated in the U.S. is small—one in 500.  相似文献   
12.
Information technology, that assortment of technology that enables the conversion of data into information, has had an enormous impact on the field of public administration and its theoretical foundation. This article explores five of them. It begins with a discussion of one of the primary impacts of information technology on public administration theory: the development of systems theory and its descendants including the study of complex systems, chaos, and complexity theory. The importance of information technology in decision-making is explored next. Does information technology free us from the limits of bounded rationality or are we simply overwhelmed by the volume of information available via new sources, such as the Internet and the World Wide Web? The third role examined is the use of information technology as a research tool to make previously intractable problems solvable. Computer capability has enormously advanced the theoretical underpinnings of public administration. Fourth, the significance of information technology as a change agent that calls for revision of other theoretical postulates is investigated. As information technology has diffused into public organizations, how has it called into question what we previously thought about the foundation of bureaucracy? Finally, learning by doing and the manner through which practice informs theory is considered.  相似文献   
13.
LONGITUDINAL STUDY OF PROCRASTINATION, PERFORMANCE, STRESS, AND HEALTH:   总被引:7,自引:0,他引:7  
Abstract— Procrastination is variously described as harmful, innocuous, or even benefical. Two longitudinal studies examined procrastination among students. Procrastinators reported lower stress and less illness than nonprocrastinators early in the semester, but they reported higher stress and more illness late in the term, and overall they were sicker. Procrastination thus appears to be a self-defeating behavior pattern marked by short-term benefits and long-term costs.  相似文献   
14.
This study builds on previous theory of planned behavior (TPB) studies in which we identified the beliefs and values which predict intention to commit driving violations. Four short experimental videos were developed in order to assess the effectiveness of an intervention grounded in the TPB. Three of the videos featured the major constructs of the TPB model. The fourth video featured anticipated regret, an addition to the TPB model which had previously been shown to add significantly to its predictive performance (Parker, Manstead, & Stradling, 1995). Results indicated that two of the videos brought about statistically significant belief changes with respect to scores on TPB items, and significant changes in general attitudes toward speeding. Discussion centers on the problems encountered in operationalizing the TPB constructs and on the potential of theory-based interventions to induce attitude change.  相似文献   
15.
We studied the course of aggressive behavior in an epidemiologically defined sample of first graders with and without comorbid anxious symptoms. Our primary purpose in doing so was to understand whether the stability of aggression in young children was attenuated or strengthened in the presence of comorbid anxiety. Previous studies of older children and adolescents had produced equivocal findings in this regard. Data on anxious symptoms were obtained through an interview of the children, whereas aggressive behavior was assessed through the use of a teacher interview and peer nominations. Assessments were performed in the fall and spring of first grade. In contrast to children classified as aggressive alone in the fall of first grade, boys and girls classified as aggressive and anxious in the fall of first grade were significantly more likely to be classified as aggressive in the spring in terms of teacher ratings and/or peer nominations of aggression. Thus our findings suggest that the link between early and later aggression may be strengthened in the presence of comorbid anxious symptoms, rather than attenuated. Future studies are needed to identify the mechanisms by which the course of aggression is influenced by the presence of comorbid anxiety.The writing of this paper was supported by the following National Institute of Mental Health grants: Epidemiologic Prevention Center for Early Risk Behavior (P50 MH38725); Periodic Outcome of Two Preventive Trials (1RO1 MH42968). The authors would like to thank the Baltimore Public City School System and the children and parents who participated in this study.  相似文献   
16.
This study was designed to provide a detailed analysis of the parameters which interact to produce a field hockey drive. The drive was performed by an elite performer under two conditions of uncertainty (Blocked and Random). The subject was asked to drive a field hockey ball toward a specified target. In the Blocked condition the speed of the approaching ball remained constant (20, 30 and 40 m.p.h.) while in the Random condition these speeds were randomly assigned to each trial. Cine analysis of the subject's successful responses under the two experimental conditions led to an investigation of the kinematics, phasing, and timing of the stroke. The subject placed emphasis upon varying the initial phases of the stroke (i.e., backswing and preparatory phases) in order to produce a temporally consistent ballistic downswing to ball contact. It seemed likely that the subject appraised the ball speed that was being delivered and then incorporated additional stick movement to ‘mark time’ before initiating temporally consistent movement phases, as spatial uncertainty increased, the subject delayed her response initiation, but then tended to respond in intervals of one reaction time for each stroke phase. Consistency was evident for displacement and initiation point values, but to a lesser extent than existed for the other variables. However, as a result of this adjustment in spatial location and displacement of the stick end during the preliminary phases of the response, the subject was able to produce a consistent and accurate ballistic downswing.  相似文献   
17.
18.
Analysis of the elements of attention: A neuropsychological approach   总被引:15,自引:0,他引:15  
A model for conceptualizing the components or elements of attention is presented. The model substitutes for the diffuse and global concept of attention a group of four processes and links them to a putative system of cerebral structures. Data in support of the model are presented; they are derived from neuropsychological test scores obtained from two samples, the first consisting of 203 adult neuropsychiatric patients and normal control subjects, and the second, an epidemiologically-based sample of 435 elementary school children. Principal components analyses of test scores from these two populations yielded similar results: a set of independent elements of attention that are assayed by different tests. This work presents a heuristic for clinical research in which the measurement of attention is essential.  相似文献   
19.
The more the deviation from a sex-and-grade, self-concept score norm (as indexed on a pair-comparisons, adjectival inventory), the greater the incidence of reported drug use. This assertion applies (a) to both sexes (teenagers) for beer and wine, cigarettes, hard liquor, and marijuana, and (b) to males alone for speed and LSD.The first-named author developed the deviancy scale; both authors processed data. In the latter task, they were assisted by Mrs. Edith P. Ferguson, wife of second-named author.  相似文献   
20.
Previous research had indicated that there were differences in the kinds of stimulus information processed by concentrated and distributed attention in peripheral vision. Concentrated attention was necessary for perceiving line arrangement differences, while line slant differences could be detected with distributed attention. However, experiments with foveal presentation showed no facilitation by concentrating attention. Experiment I replicated these results. Experiment II showed that distributed attention did degrade foveal line arrangement discrimination if the attention system was overloaded by increasing the number of elements in the array. Experiment III demonstrated that high element density was not a sufficient condition for these effects to occur. Line arrangement discrimination was reduced as letter number increased even when maximum density was held constant. In Experim~ent IV, it was shown that concentrating attention facilitated line arrangement discrimination relative to line slant discrimination in foveal vision when element number and density were held constant. The results are discussed in terms of several models postulating a difference between spread-out and concentrated attention systems.  相似文献   
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