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991.
992.
David Nicholas Paul Huntington Hamid R. Jamali Tom Dobrowolski 《Information processing & management》2007
The paper delineates and explains an emerging, but significant, form of digital information seeking behaviour among information consumers, which the authors have called ‘bouncing’. The evidence for this behaviour has emerged from five years of deep log analysis studies – an advanced form of transaction log analysis – of a wide range of users of digital information resources. Much of the evidence and discussion provided comes from the scholarly communication field. Two main bouncing metrics were applied in the log studies: site penetration, which is the number of items or pages viewed in a session, and return visits. The evidence shows that (1) a high proportion of people view just a few items or pages during a visit to a site and, (2) a high proportion of visitors either do not come back to the site or they did so infrequently. Typically those who penetrated a site least tended to return the least frequently. These people are termed ‘bouncers’. They bounce into the site and then bounce out again, presumably, to another site, as a high proportion of them do not appear to come back again. Possible explanations – negative and positive, for the form of behaviour are discussed. 相似文献
993.
Santosh Kumar Singh Achyut Narayan Kesari Prashant Kumar Rai Geeta Watal 《Indian journal of clinical biochemistry : IJCB》2007,22(2):48-52
The present study reveals the effect of Musa paradisiaca stem juice on blood glucose level (BGL) of normal & diabetic rats.
The dose of 500 mg/kg bodyweight produces a significant rise of 28.3% in blood glucose level after 6h of oral administration
in normal rats. Whereas, in sub diabetic rats the same dose produces a rise of 16.4% in blood glucose levels within 1h during
glucose tolerance test (GTT) and a rise of 16% after 4 h in fasting blood glucose levels of severe diabetic cases. These results
were unexpected and important to report as other species of Musa like Musa sapientum has been reported for its hypoglycemic
effect. 相似文献
994.
995.
Alka Singh Sheila Uthappa V. Govindaraju T. Venkatesh 《Indian journal of clinical biochemistry : IJCB》2002,17(1):25-28
The present study conducted on twenty-five uncomplicated cases of acute myocardial infarction diagnosed by clinical and electrocardiographic
findings indicated significantly increased level of cardiac Troponin-T and increased activities of the enzymes total creatine
kinase, creatine kinase-MB, aspartate transaminase and lactate dehydrogenase as compared to the twenty-five healthy control
subjects. The level of cardiac Troponin-T and the activities of the enzymes total creatine kinase, creatine kinase-MB, aspartate
transaminase and lactate dehydrogenase was found to be higher in “Q” wave myocardial infarction patients as compared to the
non-“Q” wave and the controls. Since cardiac Troponin-T has been shown to increase in unstable angina and renal failure without
cardiac disease and creatine kinase-MB activity has been found to be normal in patients with unstable angina and increase
very slightly in patients with renal failure, it was concluded that a combination of cardiac Troponin-T and creatine kinase-MB
activity was sufficient for the early diagnosis of acute myocardial infarction. 相似文献
996.
M. Maneesh H. Jayalakshmi T A Singh Amit Chakrabarti 《Indian journal of clinical biochemistry : IJCB》2006,21(1):165-168
In view of association of diabetes mellitus and male infertility, present study was designed to investigate the functional
status of hypothalamic pituitary gonadal (HPG) axis in diabetic men. Thirty-five diabetic men (BMI 22.24±0.21) in the age
group 20–40 (30.6±4.7) years were selected. Twenty-five healthy men (BMI 23.85±0.25), in the same age group (29.5±4.8) served
as control. Blood samples were collected for hormonal and biochemical estimations. Diabetic men had significantly low serum
testosterone with low LH and FSH, hypercholesterolemia, hypertriglyceridemia, hypoalbuminemia and increased oxidative stress.
Low serum testosterone in diabetic men was accompanied by low LH and FSH; the inability of the pituitary gland to respond
appropriately to a decline in testosterone implying central effect of high serum glucose on the interaction between the nervous
and endocrine system. Nutritional deficiency, increased oxidative stress and increased aromatase activity due to excessive
body fat might have also contributed to low serum testosterone. 相似文献
997.
Extensive research has examined the validity and fairness of standardized tests in academic admissions. However, due to their underrepresentation in higher education, American Indians have gained much less attention in this research. In the present study, we examined for American Indian students (1) group differences on SAT scores, (2) the predictive and incremental validity of SAT over high school grades, (3) the effect of socioeconomic status on SAT validity, (4) differential prediction in the use of SAT scores, and (5) potential omitted variables that could explain differential prediction for American Indian students. Results provided evidence of predictive and incremental validity of SAT scores, and the validity of SAT scores was largely independent of socioeconomic status. Overprediction was found when using SAT scores to predict college performance and it was reduced when including high school grades as an additional predictor. This study provides substantial evidence of the validity and fairness of SAT scores for American Indians. 相似文献
998.
The aim of this largely pedagogical article is to employ pre-college physics to arrive at an understanding of a system as complex as a nuclear reactor. We focus on three key issues: the fuel pin, the moderator, and lastly the dimensions of the nuclear reactor. 相似文献
999.
Requirements for reasoning, explaining, and generalizing mathematical concepts increase as students advance through the educational system; hence, improving overall mathematical proficiency is critical. Mathematical proficiency requires students to interpret quantities and their corresponding relationships during problem‐solving tasks as well as generalizing to different contexts; both requirements are particularly challenging for many students with learning disabilities. An in‐depth review of research was completed to (1) demonstrate how interventions targeting mathematical problem solving are categorized into heuristic, semantic, or authentic approaches; (2) explore the degree to which generalization is presented in each approach; and (3) determine the efficacy of each intervention approach. Experimental studies (n = 17) demonstrating the effects of interventions designed to enhance mathematical problem solving for secondary students with or at risk of learning disabilities were analyzed. Findings indicate that the efficacy of the three intervention approaches varies, and that the real‐world connections differ. Implications for research and practice are discussed. 相似文献
1000.