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991.
Computer terminal memory performance in a resource sharing distributed supercomputing environment is analysed with Erlang arrivals, synchronous transmission and single server random interruptions through a Bernoulli sequence of independent random variables. A new method to derive a closed expression for data arrivals with Erlangly distributed interarrival times is presented. A simple and easy approach to derive the steady state probability expressions of the terminal memory content process is presented. The memory performance is studied in terms of overflow probability and average queueing delay. The results portrayed on graphs will provide an insight about system response time and performance to the system designers. 相似文献
992.
A. K. Pradhan A. K. Shukla M. V. R. Reddy N. Garg 《Indian journal of clinical biochemistry : IJCB》2004,19(1):83-87
Oxidative stress was assesed by estimating lipid peroxidation product (LPO) in the form of thiobarbituric acid reactive substances
(TBARS), enzymatic antioxidants in the form of superoxide dismutase (SOD), catalase and nonenzymatic antioxidant vitamins
e.g. vitamin C, β carotene and vitamin E in either serum or plasma or erythrocytes in 190 cases of age related cataract in
the age group of 50–80 years. 190 cases were grouped into three morphological types namely, 73 cases of cortical, 77 cases
of posterior subcapsular and 40 cases of nuclear cataract and values of LPO and antioxidants were compared with 78 cases of
age matched healthy control groups. Plasma TBARS levels were cataract cases when compared with control groups. There were
no significant differences in the erythrocyte levels of catalase and plasma levels of Vit E between cataract cases and control
groups. No significant changes of parameters were seen among three different morphological types of age related cataract.
The present study shows that the oxidative stress may play an important role in the age related cataract. 相似文献
993.
A. Bhise P. V. Krishnan R. Aggarwal M. Gaiha J. Bhattacharjee 《Indian journal of clinical biochemistry : IJCB》2005,20(2):4-9
The present study comprised 100 patients of essential hypertension who were screened for fasting hyperinsulinemia, which was
detected in 77% cases. Twenty such hyperinsulinemic cases were subjected to 4 weeks of dietary control phase followed by 6
weeks of omega-3 fatty acids substitution [either 0.6 g/d (group 1) or 1.2 g/d (group 2)]. The mean basal fasting plasma insulin
levels were significantly higher (p<0.001) in patients of hypertension when compared to normal controls (126.51±80.36 and
19.35±12.61 μU/ml respectively). At the end of 4 weeks of diet control only, no significant change was observed in any parameter.
After substitution of omega-3 fatty acid, a significant reduction of fasting plasma insulin levels in both group 1 (29%) and
group 2 (22.8%) was observed (p<0.001). Significant reduction of systolic and diastolic blood pressure (16.4% and 25% respectively),
serum cholesterol, triglycerides and low density lipoprotein was also noted in both groups (p<0.001), while high density lipoprotein
increased by ∼8 mg% in both groups. Thus omega-3 fatty acid substituion in low dose along-with curtailment of dietary omega-6
fatty acid may be used as an adjunctive measure in the management of essential hypertension. 相似文献
994.
Palani Damotharan Anguchamy Veeruraj Muthuvel Arumugam Thangavel Balasubramanian 《Indian journal of clinical biochemistry : IJCB》2016,31(1):57-67
This study is designed to isolate and purify a novel anti-clotting protein component from the venom of Enhydrina schistosa, and explore its biochemical and biological activities. The active protein was purified from the venom of E. schistosa by ion-exchange chromatography using DEAE-cellulose. The venom protein was tested by various parameters such as, proteolytic, haemolytic, phospholipase and anti-coagulant activities. 80 % purity was obtained in the final stage of purification and the purity level of venom was revealed as a single protein band of about 44 kDa in SDS-polyacrylamide electrophoresis under reducing conditions. The results showed that the Potent hemolytic activity was observed against cow, goat, chicken and human (A, B and O positive) erythrocytes. Furthermore, the clotting assays showed that the venom of E. schistosa significantly prolonged in activated partial thromboplastin time, thrombin time, and prothrombin time. Venomous enzymes which hydrolyzed casein and gelatin substrate were found in this venom protein. Gelatinolytic activity was optimal at pH 5–9 and 1H NMR analysis of purified venom was the base line information for the structural determination. These results suggested that the E. schistosa venom holds good promise for the development of novel lead compounds for pharmacological applications in near future. 相似文献
995.
Patrocinio Zaragoza-Sáez Enrique Claver-Cortés Bartolomé Marco-Lajara Mercedes Úbeda-García 《知识管理研究与实践》2016,14(4):489-501
Knowledge creation is one of the most important dynamic capabilities that firms can use to develop new assets, which can represent the basis for future innovations. Within a context of growing globalisation, the acquisition and creation of knowledge is one of the main objectives sought with international expansion. The consideration of intellectual capital within the knowledge creation process in subsidiaries offers an innovative way to undertake knowledge management practices in multinationals. Theoretical and empirical works can be found in the literature about intellectual capital. However, very few studies link intellectual capital to knowledge creation in multinationals. Seeking to fill this gap, the purpose of this paper is to develop and test a model that includes the main intangibles belonging to structural and relational capital that can influence knowledge creation in Spanish subsidiaries of foreign multinational firms belonging to high-technology and knowledge-intensive sectors. Theoretical, empirical and managerial contributions result from this paper. 相似文献
996.
Are preservice teachers prepared to teach struggling readers? 总被引:1,自引:0,他引:1
Reading disabilities such as dyslexia, a specific learning disability that affects an individual’s ability to process written
language, are estimated to affect 15–20% of the general population. Consequently, elementary school teachers encounter students
who struggle with inaccurate or slow reading, poor spelling, poor writing, and other language processing difficulties. However,
recent evidence may suggest that teacher preparation programs are not providing preservice teachers with information about
basic language constructs and other components related to scientifically based reading instruction. As a consequence preservice
teachers have not exhibited explicit knowledge of such concepts in previous studies. Few studies have sought to assess preservice
teachers’ knowledge about dyslexia in conjunction with knowledge of basic language concepts. The purpose of the present study
was to examine elementary school preservice teachers’ knowledge of basic language constructs and their perceptions and knowledge
about dyslexia. Findings from the present study suggest that preservice teachers, on average, are able to display implicit
skills related to certain basic language constructs (i.e., syllable counting), but fail to demonstrate explicit knowledge
of others (i.e., phonics principles). Also, preservice teachers seem to hold the common misconception that dyslexia is a visual
perception deficit rather than a problem with phonological processing. Implications for future research as well as teacher
preparation are discussed. 相似文献
997.
This paper uses results from a national survey of teachers in England to test a hypothesised model of teacher orientation to learning (consisting of beliefs, practice and experiences about learning) and its relationship to teacher learning change. Results from a structural equation modeling process of 1126 teacher survey responses show that teachers bring an internal, external and collaborative orientation to their professional learning. The beliefs and practices associated with these orientations are also shown to have a moderate influence, via path analysis, on teacher learning change defined as a composite outcome of change in beliefs, practices and students. 相似文献
998.
Adrianna Kezar 《Innovative Higher Education》2011,36(4):235-247
This article examines a common problem in higher education – how to create more widespread use of improved practices, often
commonly referred to as innovations. I argue that policy models of scale-up are often advocated in higher education but that
they have a dubious history in community development and K-12 education and that higher education leaders should shirk policymakers’
push to use a scale-up model of change. These thoughts are conceptual and are based upon a critical review of literature in
community development and K-12, but I also draw upon empirical data in reviewing examples of widespread use of innovations
in higher education. 相似文献
999.
1000.