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141.
Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-invasive PPG technique to detect the blood pulse signal on toe with infrared (IR) photo sensor. A protocol consisting of two postures, i.e., supine and 45° reclining, was designed to conduct laboratory trial in this study. During the period of performing the protocol of these postures, the lower limb was passively raised from the heights of 10 cm to 60 cm randomly and individually with sponge blocks underneath the foot. Results: In the supine posture, the higher the foot was passively raised, the more the blood PPG signal decreased. In the 45° reclining posture, the blood PPG signal increased at the beginning and then decreased in the foot height position from 10 cm to 60 cm. In both postures the normalized AC signal changes significantly while the normalized DC signal changes little. Conclusion: The toe PPG signals can obviously indicate the regulated blood volume change with the designated postural procedures due to the heart level position.  相似文献   
142.
Females are underrepresented in certain disciplines, which translates into their having less promising career outlooks and lower earnings. This study examines the effects of socio-economic status, academic performance, high school curriculum and involvement in extra-curricular activities, as well as self-efficacy for academic achievement on choices of academic disciplines by males and females. Disciplines are classified based on Holland’s theory of personality-based career development. Different models for categorical outcome variables are compared including: multinomial logit, nested logit, and mixed logit. Based on the findings presented here, first generation status leads to a greater likelihood of choosing engineering careers for males but not for females. Financial difficulties have a greater effect on selecting scientific fields than engineering fields by females. The opposite is true for males. Passing grades in calculus, quantitative test scores, and years of mathematics in high school as well as self-ratings of abilities to analyze quantitative problems and to use computing are positively associated with choice of engineering fields.  相似文献   
143.
Third-, sixth-, and ninth-grade teachers in a Wisconsin county nominated 982 children as consistently displaying socially approved behavior and 568 as consistently displaying aggressive-disruptive behavior in the classroom. Five years after the original nominations teacher grades in English, science, mathematics, and social studies; rank in graduating class for original ninth graders; and STEP scores were obtained. Analyses of covariance (ANACOVA) were made with IQ as the covariate and behavior, grade, sex, and home location as the independent variables. The results indicate clearly that the children whose behavior was aggressive and disruptive in the classroom achieved at significantly lower levels than their socially approved peers.  相似文献   
144.
This paper presents results of a longitudinal study in the transition to independent graduate studies in mathematics. The analysis of the data collected from 24 students doing a PhD in mathematics revealed the existence of three transitional stages within the PhD degree, namely Adjustment, Expertise and Articulation. The focus is on the first two transitional stages, since the data collection focused mainly on these. Based on the first two transitional stages and the students’ ways of dealing with them, which were called ‘survival strategies’, three types of students were identified. The importance of motivation for each transitional stage and the successful transition overall are considered as well.  相似文献   
145.
Organizations are increasingly concerned about human resource accountability and have turned to HR metrics as an economical way to assess results from human resource activities. Unfortunately, many existing development metrics have limited utility. In this article, we review and discuss existing metrics for employee development. Then, we present five new development metrics and that can provide a core set of metrics for any type of organization. These metrics will provide new perspectives that older metrics do not, and lead to better human resource development decisions.  相似文献   
146.
This paper reports on a study of the role of parent governors in five neighbouring rural primary schools in Zimbabwe. The study proposed that despite the presence of a legal decentralised school governance structure in which parents form the majority, they did not have the capacity to function effectively therein, and were still marginalised in school governance decision-making. Four areas of decision-making were investigated: school organisation; curriculum; employment and appraisal of teaching staff; and financial resources. Interviews were conducted with parent governors, school heads and teachers. Findings show that all the respondent groups perceived significant parental involvement in the area of school finances only. However, parents were perceived to lack the capacity to make decisions in all four areas. The study concludes that the role of parents in the running of schools in the country has not significantly grown from that of being school financiers and builders of infrastructure. Therefore, building school governance capacity among parents is necessary.  相似文献   
147.
This study was designed to identify characteristics of family functioning that relate to suicide potential in an outpatient adolescent population. Participants included 51 adolescents between the ages of 14 and 18 who were involved in outpatient counselling. The Family Environment Scale and the Suicide Probability Scale were used to assess adolescents’ perception of family social climate and degree of suicide risk respectively. Results revealed significant correlations between suicide risk and family systems characterized by heightened conflict and lower levels of cohesion, independence, and organization. A stepwise multiple regression analysis suggested that organization (related to clarity and structure in family activities and responsibilities) was the strongest predictor of suicide risk. Implications for research and practice are considered.  相似文献   
148.
Motor performance is an important health resource. Review articles revealed a decline of motor performance of approximately 10?% between 1975 and 2006. In the past most of the data available for such comparisons came from ad hoc studies with non-standardized methods. Within the framework of the ”Motorik-Modul“ (MoMo) study as part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), it is possible for the first time to directly compare two cohorts in the ages of 4–17 years in a nationally representative database for Germany. The aim of this article is to report changes in motor performance of children and adolescents in the time period 2003–2006 (cohort baseline n = 4528) compared to 2009–2012 (cohort wave 1, n = 2820). Overall, it is clearly shown that the motor performance of children and adolescents in Germany did not decrease within the observational period of 6 years. The comparison of mean values of the baseline cohort compared to those of wave 1 showed that 28 out of 52 mean values of the two cohorts with a high probability did not differ based on 95?% confidence intervals (CI). In 24 out of the 52 mean values positive changes could be noted based on the individual 95?% CI values. There were more positive changes in primary school aged children than in other age groups. Within these positive changes, most effect sizes were small to medium. The results indicate that recent activities aiming at elevating motor performance levels may have started to make an impact and should be expanded, also in secondary schools. The comparative cohort study presented in this article is currently being checked by the ongoing MoMo wave 2 survey of 2014–2017.  相似文献   
149.
India seems to have the highest prevalence of osteoporosis. With growing awareness of osteoporosis and its impact on life span especially in India, special attention is being paid to early detection, management and treatment of postmenopausal osteoporosis in women. Measurement of BMD and osteocalcin are of value in estimating bone turnover rates. The aim of this study is (1) to measure the specific, sensitive bone formation marker such as osteocalcin and BMD in postmenopausal osteoporosis women and postmenopausal non-osteoporosis women; (2) the follow up study to evaluate the impact of specific antiresorptive therapy (alendronate + calcium + vitamin D) regimen in postmenopausal osteoporosis by assaying osteocalcin and BMD. Sixty clinically diagnosed postmenopausal osteoporosis patients and 60 normal subjects (postmenopausal non-osteoporosis women) were recruited as control. Mean bone mineral density T score and Z score was significantly decreased (P < 0.001) in postmenopausal osteoporosis patients as compared to controls. Highly significant increase in the mean score of BMD—T score and Z score from baseline to post therapy of 3 months was observed in postmenopausal osteoporosis women. Serum osteocalcin levels were significantly increased (P < 0.001) as compared to control group. Serum osteocalcin levels were decreased significantly (P < 0.001) from baseline to post therapy of 3 months in postmenopausal osteoporosis women. BMD is the best quantifiable predictor of osteoporotic fracture and osteocalcin is specific, sensitive, promising, currently used marker for better prognosis of osteoporosis and for monitoring responses to antiresorptive therapy.  相似文献   
150.
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