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61.
Cut‐scores were set by expert judges on assessments of reading and listening comprehension of English as a foreign language (EFL), using the bookmark standard‐setting method to differentiate proficiency levels defined by the Common European Framework of Reference (CEFR). Assessments contained stratified item samples drawn from extensive item pools, calibrated using Rasch models on the basis of examinee responses of a German nationwide assessment of secondary school language performance. The results suggest significant effects of item sampling strategies for the bookmark method on cut‐score recommendations, as well as significant cut‐score judgment revision over cut‐score placement rounds. Results are discussed within a framework of establishing validity evidence supporting cut‐score recommendations using the widely employed bookmark method. 相似文献
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The purpose of this study was to evaluate the relationship between the physicochemical properties of saliva such as flow rate,
pH, buffering capacity, calcium level, total protein and total antioxidant levels in caries free and caries active children.
The present study included one hundred and twenty healthy children who were divided into two groups; group I and group II
comprising of age groups 7–10 and 11–14 years, respectively. Both the groups were then sub-divided equally according to gender.
They were further divided into caries free and caries active with 15 children in each group. Unstimulated saliva was collected
by suction method and flow rates were determined. The samples were then analyzed for pH, buffering capacity, total protein,
calcium and total antioxidant capacity. The data was statistically analyzed using student t test (unpaired). The results revealed that when all these parameters were compared among the caries free and caries active
children, flow rate, pH, buffering capacity were slightly reduced in caries active children, but total protein and total antioxidant
capacity of saliva increased significantly in caries active children and the total calcium decreased significantly in caries
active children. Within the limitation of this study, we conclude that, the physicochemical properties of saliva play a major
role in the development of caries. 相似文献
63.
Anand B. Shetty 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(2):147-155
Leg power is an essential component for success in sports and athletic performance. Therefore, the leg power measurement may help athletes, coaches, athletic trainers, and rehabilitation specialists in selecting, treating, and training athletes for a specific sport. Using a conventional ‘jump and reach’ test, one can accurately predict the leg power and success in anaerobic‐type sports. Nineteen untrained male subjects performed ‘jump and reach’ vertical jumps on a force platform. Power values were calculated from the force versus time data obtained from the force platform. A regression equation was obtained to predict the power values using the weight of an individual and the ‘jump and reach’ height as independent variables. The regression equation is given by p = ‐666.3+14.74 [Mass (kg)] +1925.72 [Height (m)]; [R‐square = 0.69, p<0.05]. 相似文献
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A. Madhusudhana Rao R. Apoorva Usha Anand C. V. Anand G. Venu 《Indian journal of clinical biochemistry : IJCB》2012,27(3):253-258
End stage renal disease (ESRD) patients on hemodialysis (HD) have an increased oxidative stress, with a high risk of atherosclerosis and other co-morbid conditions. Recent studies have suggested that myeloperoxidase (MPO)—mediated oxidative stress may play a role in the pathogenesis of cardiovascular complications in dialysis patients. Furthermore, dialysis treatment ‘per se’ can aggravate oxidative stress. Hence this study was designed to determine whether HD leads to an alteration in the plasma levels of MPO and malondialdehyde (MDA), a marker of oxidative stress in ESRD patients on maintenance HD. To study the effect of HD, plasma MPO and MDA were determined before and after HD in forty ESRD patients (24 men and 16 women, age between 8 and 71 years, median being 40.5 years) on maintenance HD. Plasma MPO and MDA were assayed by spectrophotometric methods. Haematological and other biochemical parameters were obtained from patients’ case records. Plasma MPO and MDA levels were significantly higher after HD when compared with pre-dialysis levels (p < 0.05). There was no correlation between MPO and MDA (r = 0.184, p = 0.10) and other biochemical parameters (p > 0.05). However, there was a significant correlation between MPO and MDA with haemodialysis vintage (p < 0.05). In univariate regression analysis duration of HD (β = 1.470, p = 0.045, β = 0.388, p = 0.013), was independently associated with MPO and MDA. Although HD is indispensable for survival of patients with ESRD, it is fraught with undesirable side-effects, such as an increase in the plasma MPO and MDA levels. The elevated levels of MPO contribute to the increased oxidative stress as free radicals are produced by the reaction catalyzed by it. 相似文献
66.
This research primarily examines the stages hypothesis of the process of technology adoption by management personnel of organizations in the supply chain sector involving the Initiation, Experimentation, and Implementation stages. Further, this research examines key antecedents that may influence the various stages, including top management support, external pressure, and organization size. Using responses provided by top management representatives of 210 supply chain organizations on their organizations’ engagement with Radio Frequency Identification (RFID) technologies, this research finds that the stages hypothesis holds for RFID technologies. Specifically, organizations were seen to sequentially progress through the Initiation, Experimentation, and Implementation stages. Over 80% of organizations, who had reached the Implementation stage of adoption, had gone through the Initiation and Experimentation stages as well. Additionally, the data showed that the antecedents exerted varying levels of influences on the three stages. Top management support strongly influenced all three stages; external pressure influenced the Initiation and Implementation stages, and organizational size influenced Experimentation and Implementation stages. The paper discusses several implications for research and practice. 相似文献
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Aldo-Jonathan Muñoz-Vázquez Anand Sánchez-Orta Vicente Parra-Vega 《Journal of The Franklin Institute》2019,356(1):268-275
It is well known that a fractional-order system with a continuous right hand side does not have finite-time stable equilibria, but the discontinuous case has remained elusive in literature. Thus, based on novel mathematical tools, recently published in literature, it is demonstrated that attaining finite-time stable equilibria is not possible for a fractional-order system, not even in the case of an impulsive or discontinuous feedback. In consequence, it is demonstrated that, for a fractional-order system, a Lyapunov stable equilibrium cannot be at the same time finite-time stable. 相似文献
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