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排序方式: 共有85条查询结果,搜索用时 37 毫秒
1.
Lehman Barbara J.; Taylor Shelley E.; Kiefe Catarina I.; Seeman Teresa E. 《Canadian Metallurgical Quarterly》2009,28(3):338
[Correction Notice: An erratum for this article was reported in Vol 28(4) of Health Psychology (see record 2009-10284-005). A URL for supplemental materials was included due to a production error. There are no supplemental materials for this article.] Objective: Low childhood socioeconomic status (CSES) and a harsh early family environment have been linked with health disorders in adulthood. In this study, the authors present a model to help explain these links and relate the model to blood pressure change over a 10-year period in the Coronary Artery Risk Development in Young Adults sample. Design: Participants (N = 2,738) completed measures of childhood family environment, parental education, health behavior, and adult negative emotionality. Main Outcome Measures: These variables were used to predict initial systolic and diastolic blood pressure (SBP and DBP, respectively) and the rate of blood pressure change over 10 years. Results: Structural equation modeling indicated that family environment was related to negative emotions, which in turn predicted baseline DBP and SBP and change in SBP. Parental education directly predicted change in SBP. Although African American participants had higher SBP and DBP and steeper increases over time, multiple group comparisons indicated that the strength of most pathways was similar across race and gender. Conclusion: Low CSES and harsh family environments help to explain variability in cardiovascular risk. Low CSES predicted increased blood pressure over time directly and also indirectly through associations with childhood family environment, negative emotionality, and health behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
RA Dickson MV Seeman 《Canadian Metallurgical Quarterly》1997,154(12):1792; author reply 1793-1792; author reply 1794
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Parlikar T.A. Chang W.S. Qiu Y.H. Seeman M.D. Perreault D.J. Kassakian J.G. Keim T.A. 《Mechatronics, IEEE/ASME Transactions on》2005,10(5):482-494
In conventional internal combustion engines, engine valve displacements are fixed relative to crankshaft position. If these valves were actuated as a variable function of crankshaft angle, significant improvements in fuel economy could be achieved. To this end, a new type of electromagnetic valve drive system (EMVD) for internal combustion engines was more recently proposed. This EMVD incorporates a disk cam with a very desirable nonlinear profile which that functions as a nonlinear mechanical transformer. Modeling and simulation results showed significant advantages of this EMVD over previously designed electromagnetic engine valve drives. In this articles, we describe an experimental implementation of the proposed EMVD, which was developed to confirm these benefits. The EMVD apparatus was designed, constructed, and integrated into a computer-controlled experimental test stand. The experimental results confirm the benefits of using a nonlinear mechanical transformer in a motordriven engine-valve spring system, as seen in the small average power consumption and low valve seating velocity. In addition, a valve transition time sufficient for 6000-rpm engine operation was achieved. The results also suggest ways to improve the EMVD apparatus in the future. 相似文献
4.
The authors review evidence regarding the biological processes that may link religiosity/spirituality to health. A growing body of observational evidence supports the hypothesis that links religiosity/spirituality to physiological processes. Although much of the earliest evidence came from cross-sectional studies with questionable generalizability and potential confounding, more recent research, with more representative samples and multivariate analysis, provides stronger evidence linking Judeo-Christian religious practices to blood pressure and immune function. The strongest evidence comes from randomized interventional trials reporting the beneficial physiological impact of meditation (primarily transcendental meditation). Overall, available evidence is generally consistent with the hypothesis that religiosity/spirituality is linked to health related physiological processes--including cardiovascular, neuroendocrine, and immune function--although more solid evidence is needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Dr. Jeffrey I. Seeman 《Israel journal of chemistry》2018,58(1-2):28-44
The relationship between classical structure determination and retrosynthetic analysis combined with total synthesis is examined in detail. The chemical degradation steps in the former are the counterparts of the retrosynthetic steps in the latter. And the gedankenexperiment, also known as “paper chemistry,” working forward and solving the structure from the degradation data, is the counterpart of the experimental forward steps in a total synthesis. The wide use of genealogic-like “trees” to organize and illustrate many reaction sets in organic chemistry is discussed. Excerpts from the writings of Sir Robert Robinson, R. B. Woodward, and Carl Djerassi reveal historically important insights about these activities in the 1940s–1960s. 相似文献
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Seeman Teresa; McAvay Gail; Merrill Susan; Albert Marilyn; Rodin Judith 《Canadian Metallurgical Quarterly》1996,11(3):538
Data from a cohort of relatively high functioning, older men and women were used to test the hypothesis that stronger self-efficacy beliefs predict better maintenance of cognitive performance. Structural equation modeling revealed that stronger baseline instrumental efficacy beliefs predicted better verbal memory performance at follow-up among men but not among women, controlling for baseline verbal memory score and sociodemographic and health status characteristics. For both men and women there were no significant associations between either type of self-efficacy beliefs and measures of nonverbal memory, abstraction, or spatial ability. Consistent with previous research showing relationships between baseline cognitive performance and change in self-efficacy beliefs, better abstraction ability was also predictive of increases in instrumental efficacy beliefs among the men. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Wood R.J. Avadhanula S. Steltz E. Seeman M. Entwistle J. Bachrach A. Barrows G. Sanders S. 《Robotics & Automation Magazine, IEEE》2007,14(2):82-91
This article has concentrated on the development of a set of core technologies key to the realization of an autonomous 2-g glider. One aspect which was not discussed in detail was the ease of construction and low cost of an individual MicroGlider. Integration is simplified through a number of rapid prototyping techniques and the low costs of most components allow rigorous testing to be done without worry of substantial damage. 相似文献
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Circulatory changes following standardized compression trauma to the hind leg in dogs were evaluated using an electromagnetic flow meter and repeated angiography. A transient increase of flow to the injured limb and within the traumatized region was observed. Good agreement was found between the electromagnetic flow recordings and estimates of relative changes in flow by the angiographic method. 相似文献