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21.
The electromyogram (EMG) recorded with surface electrodes was examined using a triggered oscilloscope technique. When all but the high-amplitude waveforms in a given segment of activity were excluded from analysis, it was found that the duration of the remaining waveforms was specific to the muscle that produced them. That is, waveforms of a given duration were recorded whenever conventional indices-observable contraction, joint movement. needle recordings-showed activity in a specific muscle. This led to the suggestion that waveform duration might be used to validate the surface EMG. The suggestion. which is limited by the need to control posture and electrode placement, both of which may influence waveform duration, was illustrated in application to psychological research.  相似文献   
22.
Experiments studied how assimilation and contrast varied as a function of the reflectance of figures above and below the reflectance of a gray background. The results showed that for the experimental conditions investigated: (a) contrast always occurs when the reflectance of lines is above the reflectance of the background, (b) assimilation occurs when the reflectance is below that of the background, (c) circles produce the same degree of assimilation and contrast as lines of equal width, and (d) repeated judgments do not affect contrast but reduce assimilation; as line darkness and line width increase assimilation gives way to contrast following repeated judgments. The results are discussed in connection with the hypothesis that assimilation and contrast arise from opponent processes in the visual system.  相似文献   
23.
Experiments studied how assimilation and contrast varied as a function of the reflectance of figures above and below the reflectance of a gray background. The results showed that for the experimental conditions investigated: (a) contrast always occurs when the reflectance of lines is above the reflectance of the background, (b) assimilation occurs when the reflectance is below that of the background, (c) circles produce the same degree of assimilation and contrast as lines of equal width, and (d) repeated judgments do not affect contrast but reduce assimilation; as line darkness and line width increase assimilation gives way to contrast following repeated judgments. The results are discussed in connection with the hypothesis that assimilation and contrast arise from opponent processes in the visual system,  相似文献   
24.
This is a paper which reviews and discusses the implications of Chinese value systems for managerial behaviour in Taiwan. With a central assumption that managerial behaviour and styles are largely shaped by the values and normative systems of senior members of corporate management, a study of 43 industrial firms in Taiwan investigating their organisational structure and the managerial assumptions, values and other socio-demographical features of their senior managers was conducted. The results of the research lead to the construction of a typology of four managerial patterns in Taiwan today, viz. the ‘grass-roots’ type, the ‘Mainlander’ type, the ‘specialist’ type and the ‘transitional’ type. While the ‘transitional’ type is more or less by definition ‘transient’, a tendency is postulated by the authors for both the ‘grass-roots’ and ‘Mainlander’ types to move gradually to converge with the ‘specialist’ type which will become increasingly widespread in Taiwan.  相似文献   
25.
Cornell University Medical College, Westchester Division, The New York Hospital, White Plains, New York It is well established that there is a complex timekeeping mechanism in the human brain. This mechanism is associated with a variety of physiological and psychological rhythms having a period of about a day, and thus referred to as circadian rhythms. The circadian system has recently been modeled in terms of two underlying oscillators, one much more resistant to changes in routine than the other. These oscillators are considered to be endogenous, that is, internal to the organism, and not reliant for their existence upon changes in the person’s environment or general behavior. They thus continue to run even when the sleep/wake cycle is suspended, as in sustained operations. Thus, by their very nature, sustained operations require the individual to override the inputs that are coming from his or her circadian system (especially the indication that sleep is required). The aim of this paper is to provide a background to the area of circadian rhythms research, including a section on the methodology, so that the impact of the circadian system on sustained operations can be better understood.  相似文献   
26.
27.
Mental rotation in the congenitally blind was investigated with a haptic letter-judgment task. Blind subjects and blindfolded, sighted subjects were presented a letter in some orientation between 0° to 300° from upright and timed while they judged whether it was a normal or mirror-image letter. Both groups showed an increasing response time with the stimulus’s departure from upright; this result was interpreted as reflecting the process of mental rotation. The results for the blind subjects suggest that mental rotation can operate on a spatial representation that does not have any specifically visual components. Further research showed that for the sighted subjects in the haptic task, the orientation of a letter is coded with respect to the position of the hand. Sighted subjects may code the orientation of the letter and then translate this code into a visual representation, or they may use a spatial representation that is not specifically visual.  相似文献   
28.
A 39-year-old male presenting with a 5 year history of excessive urinary frequency and urgency was treated first with scheduling of urination, use of external urinary catheter and progressive muscular relaxation and then with a urinary retention training procedure. After the first set of procedures, urinary frequency decreased, whereas urgency increased slightly. After completion of retention training, both symptoms were alleviated. Overall, urinary frequency decreased from a baseline average of 14 urinations daily to a post-treatment average of 6.5 urinations per day. Urinary urgency decreased from a baseline average of 35 urges per day to a post-treatment average of 9.3 urges per day. Gains were maintained at 3 and 5 month follow-up.  相似文献   
29.
Confidentiality: a survey in a research hospital   总被引:1,自引:0,他引:1  
C Grady  J Jacob  C Romano 《The Journal of clinical ethics》1991,2(1):25-30; discussion 30-4
Despite the many justifications for protecting patient confidentiality, we recognize that confidentiality cannot be absolute. Our world of automated information and easy access and storage poses many threats to confidentiality. This paper has described a survey conducted at the NIH Clinical Center to assess the knowledge, attitudes, and behaviors of clinical physicians and nurses about confidentiality of patient information. The survey findings demonstrate the need for reminders and increased awareness about confidentiality in our setting. Most of the survey respondents had a good knowledge of what was expected of them, and they believed that confidentiality was important and maintaining it was their responsibility. Of interest was that in several simulated clinical situations, there was a discrepancy between what respondents indicated they should do and what they thought they would do. The biggest discrepancies appeared in situations that involved overhearing a patient conversation on the elevator, approaching an unfamiliar person who is reading a medical record in the nurses' station, and answering a patient's inquiry about the status of another patient. The findings support the speculation that this difference may be attributed to discomfort or decreased awareness, and not necessarily to lack of knowledge. Results indicate that policies and administrative expectations should be frequently communicated and enforced, and that educational programs that address issues of confidentiality should be provided. The results of this survey have been influential in guiding educational strategies and administrative activities at the clinical center. The clinical center initiated a confidentiality awareness campaign, displaying a new poster every three months in strategic locations and distributing other tangible reminders (such as pens, magnets, and buttons) containing the same confidentiality message.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
30.
The Psychological Record - Creativity and innovation have brought about phenomenal changes throughout human history. Art, science, medicine, industry, and technology have all grown through creative...  相似文献   
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