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991.
Elizabeth Behm-Morawitz Brandon M. Miller Jennifer Lewallen 《Communication Research Reports》2018,35(3):210-221
Content analyses of prime-time television provide a picture of predominant cultural stereotypes and social trends. The present research is a quantitative content analysis of social class in popular broadcast and cable television in the United States. This research advances scholarship by systematically analyzing character class in addition to more commonly examined variables such as race and gender. A model for the operationalization of class for quantitative content analyses of mediated texts is offered. This proof of concept study demonstrates the viability of studying media representations of class quantitatively to systematically document patterns of portrayal. 相似文献
992.
Do physical activity beliefs differ by age and gender? 总被引:1,自引:0,他引:1
Age and gender are consistently related to physical activity (PA), yet theoretical explanation for these associations is scant. The present study compared the mean values and correlations of a population sample, divided by gender and age group, with respect to theory of planned behavior beliefs (behavioral, normative, and control) and PA. Participants were a sample (N=6,739) of adults (M age=49.65, SD=16.04) who completed measures of social and health demographics, theory of planned behavior beliefs, and self-reported PA. Mean analyses identified greater perceived control over PA for seniors than for young and middle-aged adults (N>.025). Belief-behavior correlations, however, were not different across age and gender in 24 of 26 tests (q<.19). Thus, PA beliefs are invariant across age and gender with the exception of mean levels of perceived control, which are lower among younger adults than older adults. Factors such as early parenthood and career demands were considered the likely reasons for differences. Overall, the evidence suggests that adapting theoretical models for specific age groups or based on gender may not be necessary. 相似文献
993.
The University of Minnesota Medical School has an innovative curriculum, called Didactic/Selective, which provides third- and fourth-year medical students with multidisciplinary and multispecialty courses. Within this framework, the Bio-Medical Library planned a course to teach the knowledge and skills necessary for library research and information management. It included (1) searching case-related topics in print indexes, (2) formulating and processing MEDLINE searches on BRS Colleague, (3) building a personal file with PC-File or Notebook, and (4) exploring various methods for current awareness. Students' evaluations were positive, with the majority indicating that they found the course interesting and the knowledge gained substantial. 相似文献
994.
We present an overview of the special issue in this paper. The main objective is to provide information for lecturers on how
to improve the student experience, using current knowledge in the field. To this end we present an overview of six papers
covering areas as diverse as tools and methods used to support teaching and learning, pedagogical challenges in teaching mathematics
for search, etc. 相似文献
995.
Recently direct optimization of information retrieval (IR) measures has become a new trend in learning to rank. In this paper,
we propose a general framework for direct optimization of IR measures, which enjoys several theoretical advantages. The general
framework, which can be used to optimize most IR measures, addresses the task by approximating the IR measures and optimizing
the approximated surrogate functions. Theoretical analysis shows that a high approximation accuracy can be achieved by the
framework. We take average precision (AP) and normalized discounted cumulated gains (NDCG) as examples to demonstrate how
to realize the proposed framework. Experiments on benchmark datasets show that the algorithms deduced from our framework are
very effective when compared to existing methods. The empirical results also agree well with the theoretical results obtained
in the paper. 相似文献
996.
C. Albrecht A. Hanssen-Doose K. Bös L. Schlenker S. Schmidt M. Wagner N. Will A. Worth 《Sportwissenschaft》2016,46(4):294-304
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
997.
Machado M Willardson JM Silva DR Frigulha IC Koch AJ Souza SC 《Research quarterly for exercise and sport》2012,83(2):276-281
In the current study, we examined the relationship between serum creatine kinase (CK) activity following upper body resistance exercise with a 1- or 3-min rest between sets. Twenty men performed two sessions, each consisting of four sets with a 10-repetition maximum load. The results demonstrated significantly greater volume for the 3-min condition (M = 4156 kg, SD = 867, for 3 min; vs. M = 3503 kg SD = 759, for 1 min; p < .001), with no significant differences in delta CK activity between conditions (p = .574). Nevertheless, there was a weak correlation between the delta CK activity and total volume of exercise completed (r = .55 with a 1-min rest, and r = .45 with a 3-min rest). Therefore, the volume following upper body resistance exercise correlates weakly with serum CK levels, irrespective of rest interval length between sets. 相似文献
998.
999.
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
1000.
Induction of diabetes by Streptozotocin in rats 总被引:1,自引:0,他引:1
A. Akbarzadeh D. Norouzian M. R. Mehrabi Sh. Jamshidi A. Farhangi A. Allah Verdi S. M. A. Mofidian B. Lame Rad 《Indian journal of clinical biochemistry : IJCB》2007,22(2):60-64
The objective of this study is to induce experimental diabetes mellitus by Streptozotocin in normal adult Wistar rats via
comparison of changes in body weight, consumption of food and water, volume of urine and levels of glucose, insulin and C-peptide
in serum, between normal and diabetic rats. Intra-venous injection of 60mg/kg dose of Streptozotocin in adult wistar rats,
makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes mellitus
in the 2–4 days. Induction of experimental diabetes mellitus is indeed the first step in the plan of purification of pancreatic
Langerhans islet cells of normal rats for transplanting under the testis subcutaneous of experimentally induced diabetic rats.
Streptozotocin induces one type of diabetes which is similar to diabetes mellitus with non-ketosis hyperglycemia in some animal
species. For induction of experimental diabetes in male adult rats weighted 250–300 grams (75–90 days), 60mg/kg of Streptozotocin
was injected intravenously. Three days after degeneration of beta cells, diabetes was induced in all animals. The diabetic
and normal animals were kept in the metabolic cages separately and their body weight, consumption of food and water, urine
volume, the levels of serum glucose, insulin and C-peptide quantities in all animals were measured and then these quantities
were compared. For a microscopic study of degeneration of Langerhans islet beta cells of diabetic rats, sampling from pancreas
tissue of diabetic and normal rats, staining and comparison between them, were done. Induction of diabetes with Streptozotocin
decreases Nicotinamide-adenine dinucleotide (NAD) in pancreas islet beta cells and causes histopathological effects in beta
cells which probably intermediates induction of diabetes. In this study, we used Streptozotocin for our experiments in induction
of experimental diabetes mellitus. After Induction of diabetes, consumption of food and water, volume of urine and glucose
increased in the diabetic animals in comparison with normal animals, but the weight of body and the volume of insulin and
C-peptide decreased in the diabetic animals. Sampling and staining of pancreas tissue of diabetic and normal rats showed that
the Langerhans islet beta cells of diabetic rats have been clearly degenerated. In three days, Streptozotocin makes pancreas
swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes. It also changes normal
metabolism in diabetic rats in comparison with normal rats. Consumption of water and food, volume of urine, serum glucose
increases in diabetic animals in comparison with normal rats but the levels of serum insulin, C-peptide and body weight decreases. 相似文献