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21.
Purpose: The present study aimed to determine if autonomic cardiac modulation was influenced by acute exposure to normobaric hypoxia. Method: Ten healthy male lowland dwellers completed five block-randomised single-blinded, crossed-over acute exposures to a normobaric hypoxic environment, each separated by 24 hours’ recovery (20.3%, 17.4%, 14.5%, 12.0% and 9.8% FIO2). Supine recordings were made of arterial oxygen saturation and electrocardiogram (ECG). RR intervals from the ECG trace were analysed for time (SDNN, lnrMSSD), frequency (lnVLF, lnLF, lnHF, lnTP, LFnu, and HFnu), and nonlinear (DFA-α1 and SampEn) heart rate variability components. Results: A significant reduction in arterial SaO2 occurred with reduced FIO2, along with a rise in heart rate (Cohen’s d?=?1.16, 95% Confidence Interval [2.64–6.46]), significant at 9.8% FIO2. A decrease in autonomic cardiac modulation was also found as shown by a statistically significant (at 9.8% FIO2) decrease in lnTP (d?=?1.84 [1.74–1.94]), and SampEn (d?=?0.98 [0.83–1.12]) and an increase in DFA-α1 (d?=?0.72 [0.60–0.84]) from normoxia at 9.8% FIO2. Conclusion: The decrease in variability indicated a reduction in autonomic cardiac modulation. There appears to be a threshold ~9.8% FIO2 (~6000?m equiv.), below which significant alterations in autonomic control occur. 相似文献
22.
Objective
The purpose of this study was to investigate the relative effectiveness of three web-scale discovery (WSD) tools in answering health sciences search queries.Methods
Simple keyword searches, based on topics from six health sciences disciplines, were run at multiple real-world implementations of EBSCO Discovery Service (EDS), Ex Libris''s Primo, and ProQuest''s Summon. Each WSD tool was evaluated in its ability to retrieve relevant results and in its coverage of MEDLINE content.Results
All WSD tools returned between 50%–60% relevant results. Primo returned a higher number of duplicate results than the other 2 WSD products. Summon results were more relevant when search terms were automatically mapped to controlled vocabulary. EDS indexed the largest number of MEDLINE citations, followed closely by Summon. Additionally, keyword searches in all 3 WSD tools retrieved relevant material that was not found with precision (Medical Subject Headings) searches in MEDLINE.Conclusions
None of the 3 WSD products studied was overwhelmingly more effective in returning relevant results. While difficult to place the figure of 50%–60% relevance in context, it implies a strong likelihood that the average user would be able to find satisfactory sources on the first page of search results using a rudimentary keyword search. The discovery of additional relevant material beyond that retrieved from MEDLINE indicates WSD tools'' value as a supplement to traditional resources for health sciences researchers. 相似文献23.
Mary E. Westerback 《科学教学研究杂志》1982,19(7):603-616
These studies examined attitude toward teaching science (ATTS) using an adaptation of the Bratt Attitude Test (M-BAT); anxiety about teaching science (ANX-TS), as measured by the State-Trait Anxiety Inventory (STAI A-State); and selected demographic variables in preservice elementary teachers for the 1977–1978 and 1978–1979 academic years and a follow-up of those students who completed their student teaching in May 1979. The M-BAT and STAI were administered in September at the beginning of Science 6 (earth science and biology course), in December on the next to last day of Science 6, in May on the next to the last day of Science 5 (physical science), and in May 1979 after student teaching. In the two academic years, both ATTS and ANX-TS became more positive during the sequence Science 6-5. Both changes in ATTS and ANX-TS continued to change in a positive direction after completion of Science 6-5, after student teaching. There were differences in the times that the greatest changes in ATTS and ANX-TS occurred. In both studies, the greatest change in ATTS took place between September and December, during Science 6. The greatest change in ANX-TS, however, took place during Science 5 between December and May in the 1977–1978 study. In the 1978–1979 study, the greatest changes in ANX-TS occurred in Science 6, between September and December. The delayed reduction of ANX-TS in the 1977–1978 study may be explained by differences in teaching patterns. In 1977–1978, two teachers taught only their academic specialty, biology or earth science, to students who switched teachers midsemester. In 1978–1979, the same two instructors taught both biology and earth science to the same students. Correlation coefficients for successive and corresponding administrations of both the M-BAT and STAI suggest these variables are related. Students with more positive ATTS tended to have reduced ANX-TS. Neither the number of high school or college science and math courses completed nor the level of enjoyment of these courses appears to be related to ATTS or ANX-TS for the initial administration of the M-BAT and STAI. Closer examination of data, however, indicates that students with negative ATTS and high ANX-TS were fairly evenly divided in their enjoyment of mathematics, while students with positive ATTS and low ANX-TS enjoyed math in a 3:1 like/dislike ratio. The relationship between both ATTS and ANX-TS and achievement is reasonalbly consistent for Science 6. In Science 5, however, the relationship between ATTS and achievement is inconsistent and there is no indication of a relationship between achievement and ANX-TS. 相似文献
24.
Mary Darmanin 《Gender and education》1992,4(1-2):105-126
This article uses the case of Maltese girls and women to examine the relationship between schooling and the economy. It is clear that not only have education and economic planners sought to strengthen the links between school and work in planning for different courses for children of different sexes, but also that the allocation of pupils to subjects has in itself worked as a labour market. Interestingly, private schools have also responded to their interpretations of labour market demand in producing feminised choices for girls. Some Maltese girls do achieve well, compared both to Maltese boys and their European counterparts. This is largely due to a combination of single‐sex and selective secondary education. Nevertheless, these same girls continue to have lower and feminised occupational aspirations which mirror the job opportunities in the labour market. Others are incapacitated by their schooling and have until recently been channelled into the labour intensive jobs on which Malta's economy depended in the first phase of industrialisation in the 1960s and 1970s. Of late it seems as if rising educational standards and social awareness (propagated by women's organisations) have led to reluctance on the part of these girls and women to participate in the same way in the workforce. With struggle, the needs of patriarchy and capitalism will not always be perfectly served. 相似文献
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Mary H. Guindon Maryam S. Sobhany 《International journal for the advancement of counseling》2001,23(4):269-282
Most counselors recognize the importance ofcultural competence in their work. As part ofeffective treatment, skills in accuratelydiagnosing clients from diverse backgrounds areessential, yet specific techniques addressingcultural differences to aid in the diagnosisprocess are underrepresented in the counselingliterature. The purpose of this article is tooffer one step toward the development ofdiagnostic methods suitable for an increasinglydiverse client base. The importance ofcultural competency during the diagnostic phaseof counseling is discussed, the nature ofculture and its influence on diagnosis isreviewed, and a practical conceptual frameworkthat can assist counselors in makingsystematic, culturally sensitive diagnosis ispresented. 相似文献
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Mary Elizabeth McCormac 《Journal of Career Development》1988,14(3):196-204
Conclusion The ever increasing demands on guidance and counseling programs has added new responsibilities to the tasks of the counselor specifically in the area of career development. Along with this increase in responsibility, the issue of accountability has been added. Career information delivery systems assist the counselor in meeting the need for accurate, relevant occupational and educational information that can be disseminated in a timely efficient manner. Therefore, CIDS should be a vital part of all comprehensive career guidance and counseling programs.Mary Elizabeth McCormac is an Occupational Information System Specialist, National Occupational Information Coordinating Committee, Washington, D.C. 相似文献
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