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961.
A survey conducted among 187 HIV-infected patients from publicly supported HIV clinics in the Puerto Rican Southern Health Region (SHR) failed to substantiate health planners' concern that this group travels frequently to the US to receive medical services. Respondents were questioned about all places of residence and all sites of HIV treatment in the past 12 months. Movement was defined as being anywhere outside of the SHR for 2 weeks or longer. 7% of the sample had moved at least once in the past year; 4% had moved outside the SHR but within Puerto Rico, while 3% had been in the continental US. Compared to the heterosexual risk group, intravenous drug users and men who have sex with men were 7-8 times more likely to have moved. The attainment of at least a high school education was also significantly and independently associated with increased probability of movement. Medical care was not identified by any of these respondents as the primary reason for travel. 58% indicated they were in their current place of residence to be near family, friends, and relatives. Both the small sample size and the low socioeconomic status of respondents may have limited the ability of this study to identify the so-called "air bridge," however.  相似文献   
962.
The potential for communication through the kinesthetic aspect of the tactual sense was examined in a series of experiments employing Morse code signals. Experienced and inexperienced Morse code operators were trained to identify Morse code signals that were delivered as sequences of motional stimulation through up-down displacements (roughly 10 mm) of the fingertip. Performance on this task was compared with that obtained for both vibrotactile and acoustic presentation of Morse code using a 200-Hz tone delivered either to the fingertip through a minishaker or diotically to the two ears under headphones. For all three modalities, the ability to receive Morse code was examined as a function of presentation rate for tasks including identification of single letters, random three-letter sequences, common words, and sentences. Equivalent word-rate measures (i.e., product of percent correct scores and stimulus presentation rate) were nearly twice as high for auditory presentation as for vibrotactile stimulation, which in turn was about 1.3 times that for motional stimulation. The experienced subjects outperformed the inexperienced subjects by amounts that increased with task complexity. For example, the former were able to receive sentences at 18 words/min with motional stimulation, whereas the latter, following 75 h of training, were unable to perform this task. The present results and those of other research with tactual communication systems are compared, particularly regarding estimates of information-transfer rates.  相似文献   
963.
There are circumstances in which one is reluctant to express a judgment on the basis of the available information. This is for instance the case when the decision may jeopardize the integrity of the group one is a member of. In particular, ingroup members are considered less judgeable than outgroup members. This phenomenon corresponds to the ingroup overexclusion effect (Leyens and Yzerbyt, 1992). An experimental situation was designed in order to rule out an explanation of this phenomenon in terms of confirmation of hypothesis. French- or Dutch-speaking subjects heard recordings of 40 sentences and, depending on the specific wording of the question, decided whether the speakers belonged to the group of French-speaking (i.e. Walloon) versus Dutch-speaking (i.e. Flemish) Belgians or not. The 40 sentences enabled to cross three factors with five sentences in each cell: Walloon versus Flemish speakers, French versus Dutch sentences, and short versus long sentences. As predicted, subjects made most errors when ingroup members read short outgroup sentences. Most importantly, the specific wording of the question did not lead to a reversal of the pattern of errors of group identification. Subjects also took longer to make a decision about an ingroup member reading an outgroup sentence than about an outgroup member reading an ingroup sentence. Such a pattern clearly supports a motivational explanation and undermines a confirmation of hypothesis explanation of the ingroup overexclusion effect. Older accounts of ethnic identification phenomena are addressed and it is suggested that identity concerns greatly affect impression formation processes.  相似文献   
964.
应激对大鼠行为和部分脑区谷氨酸含量的影响   总被引:36,自引:1,他引:35  
以旷场试验法测定动物在急、慢性躯体性和心理性应激时的行为变化,以快速断头冷冻匀浆法,用HITACHI-835氨基酸分析仪测定应激各期视皮层、海马、下丘脑、小脑谷氨酸含量。并对正常动物经侧脑室微量注射L-AP4后观察行为变化。结果显示,急性应激期动物行为活动增加,慢性应激期减少:应激时,大鼠部分脑区的谷氨酸含量与对照组相比在不同时期呈显著性差异;侧脑室微量注射L-AP4提示行为活动减弱可能与脑内Glu系统的活动有关。  相似文献   
965.
Strong empirical evidence was obtained in support of the proposition that nonabsolute/relativistic (N/R) thinking is a unifying commonality underlying four postformal models of higher-order thinking, namely, problem finding, dialectical reasoning, relativistic operations, and reflective judgment. Within the construct of N/R thinking, two dimensions—the basic form and the epistemic view—and two levels—the formal form and the postformal form—were differentiated as hypothesized. The findings clarify logical relationships among the models as well as provide a common link unifying their diversity. Implications and suggestions for future research are provided.  相似文献   
966.
An inexpensive, professionally manufactured, digital I/O experiment control interface for any PC-compatible computer is described. It plugs into a standard printer port and provides 1-msec accuracy for up to 4 inputs and 22 outputs. It also allows experiment control procedures to be written in an easy-to-learn, easy-to-use Experiment Control language (ECBASIC). In addition to many instructions specifically designed to simplify behavioral research, ECBASIC provides for transparent collection and storage of event logs.  相似文献   
967.
This paper briefly overviews the World-Wide Web. It then provides a short tutorial on the use of the hypertext markup language to publish information on the web. Hypertext markup language is a special page-layout language that was developed to help make creating and retrieving information on the web consistent and efficient. Hyperlinks within hypertext markup language make the language especially powerful because they enable the browser to transparently retrieve images, movies, or audio files from virtually any computer on earth simply by clicking on an item displayed on the monitor.  相似文献   
968.
969.
Recently arrived and settled Salvadoran refugees and Anglo-Canadians in London, Ontario were compared with respect to psychological distress, quality of life, and life satisfaction. A matched sample of 60 participants in each group completed a demographic questionnaire, the Brief Symptom Inventory, a shortened version of the Quality of Life Questionnaire, and the Satisfaction with Life Scale in either English or Spanish. Significant group differences were obtained on measures of quality of life and life satisfaction, but not of psychological distress. The results are discussed in relation to findings with other refugee groups.  相似文献   
970.
Following Henkins discovery of partially-ordered (branching) quantification (POQ) with standard quantifiers in 1959, philosophers of language have attempted to extend his definition to POQ with generalized quantifiers. In this paper I propose a general definition of POQ with 1-place generalized quantifiers of the simplest kind: namely, predicative, or cardinality quantifiers, e.g., most, few, finitely many, exactly , where is any cardinal, etc. The definition is obtained in a series of generalizations, extending the original, Henkin definition first to a general definition of monotone-increasing (M) POQ and then to a general definition of generalized POQ, regardless of monotonicity. The extension is based on (i) Barwises 1979 analysis of the basic case of M POQ and (ii) my 1990 analysis of the basic case of generalized POQ. POQ is a non-compositional 1st-order structure, hence the problem of extending the definition of the basic case to a general definition is not trivial. The paper concludes with a sample of applications to natural and mathematical languages.  相似文献   
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