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21.
This article applies Deming's Plan‐Do‐Study‐Act (PDSA) cycle of continual improvement to a course taught with both blended and online sections. It uses Relative Proximity Theory, an extension of the Theory of Transactional Distance, to measure the quality of online/blended learning as a function of the obstacles to a student's full engagement with a course. These obstacles can arise because of the student's transactions with fellow students, with the instructor, with the course content, or from the instructional technology used in the course. Using stepwise multiple regression, the most significant obstacles can be identified. Once the obstacles are known, strategies to reduce them are planned and implemented. Logistic regression is used to determine if the realized reductions are statistically significant and for setting the stage for further improvements.  相似文献   
22.
Liquid dielectrophoresis (L-DEP), when deployed at microscopic scales on top of hydrophobic surfaces, offers novel ways of rapid and automated manipulation of very small amounts of polar aqueous samples for microfluidic applications and development of laboratory-on-a-chip devices. In this article we highlight some of the more recent developments and applications of L-DEP in handling and processing of various types of aqueous samples and reagents of biological relevance including emulsions using such microchip based surface microfluidic (SMF) devices. We highlighted the utility of these devices for on-chip bioassays including nucleic acid analysis. Furthermore, the parallel sample processing capabilities of these SMF devices together with suitable on- or off-chip detection capabilities suggest numerous applications and utility in conducting automated multiplexed assays, a capability much sought after in the high throughput diagnostic and screening assays.  相似文献   
23.
To establish/develop an assay method for measuring Ornithine Aminotransferase (EC.2.6.1.13) activity using rat brain mitochondria as a source of enzyme in presence and absence of Pyridoxal Phosphate (PLP). The modified method, with the improved sensitivity, is adopted for the assay of ornithine amino transferase activity in rat brain mitochondria. The enzyme activity was measured at 620 nm, the study showed that reaction was optimum at 37°C for 30 minutes. The assay is sensitive enough to detect activity at the order of nanomoles pyrroline-5-carboxylate/mg protein/minute and can be compared as an alternative to the radio isotopic method which is more cumbersome and aminobenzaldehyde method which is less sensitive. The Km & Vmax shows maximum activity in the presence of Pyridoxal Phosphate (Coenzyme) concentration at 0.05mM when compared with absence of Pyridoxal Phosphate as higher the concentration of Pyridoxal Phosphate affects the affinity of the enzyme to substrate. The OAT activity in different tissues of the rat was also studied and highest activity was found in liver and kidney.  相似文献   
24.
How genes evolve     
Ravi Parkash 《Resonance》1998,3(2):28-34
The increasing power of molecular techniques of gene cloning, DNA sequencing and use of restriction enzymes has revolutionised our ability to understand mechanisms of evolution at the level of genes. Exciting new findings on pseudogenes and gene elongation have led to an increased understanding of how our genes themselves change through evolutionary time, often in bizzarre ways.  相似文献   
25.
Asian Indian inversion deletion Gγ (Aγδβ)0-thalassemia is a rare entities characterized by high HbF. Due to interaction with various genetic factors, patients with Gγ (Aγδβ)0-thalassemia showed clinical variability. Here we are presenting the phenotypic expression of Gγ(Aγδβ)0 thalassemia under influence of various co-inherited factors. Patient with α-globin gene deletion had mild phenotype than the patient with β-globin mutations. Patient with alpha gene deletion were presenting clinical character like thalassemia intermedia while Gγ (Aγδβ)0-thalassemia patients with co- presence of beta thalssemia mutation clinically behaved like thalassemia major.  相似文献   
26.
The activity of six hydrolytic enzymes-carboxyl esterase, acid phosphatase, alkaline phosphatase, β-galactosidase, β-glucosidase and β-hexosaminidase, were studied in different regions of the normal human brain tissue obtained at autopsy. Protein estimation and activities of the hydrolytic enzymes with respective substrates were assayed by spectrophotometric and spectroflourometric methods. Amongst the eight regions of the brain-frontal, parietal, occipital, temporal, thalamus, cerebellum and hippocampus, the pineal gland showed highest activity for all hydrolytic enzymes studied except for carboxyl esterase. Among six hydrolases studied, hexosaminidase exhibited highest activity in all regions of the human brain while alkaline phosphatase activity was the least amongst all regions studied. A majority of the enzymes studied showed higher activity in gray matter as compared to the white matter except acid phosphatase and β-glucosidase which exhibited higher activity in the white matter. The most significant finding in the present study was the high activity of all hydrolytic enzymes noted in the pineal gland as compared to all other regions of the human brain. Such a finding has not been hitherto reported earlier in human brain tissue samples. If the specific activities of these enzymes are to be considered as any functional index, then pineal gland may be more metabolically active tissue with respect to the hydrolytic function as compared to the other regions of the brain.  相似文献   
27.
Abstract

The efforts of other nations to develop comprehensive approaches to the development and application of information technology have given rise to concern in many quarters about the adequacy of the U.S. government's response to information issues.

A bill, H.R. 3137, was introduced in the House of Representatives in April 1981 by Congressman George E. Brown, Jr., in an attempt to stimulate movement toward a coordinated development of U.S. information policies. Hearings on this legislation elicited a wide variety of opinion concerning how best to proceed toward this development. This paper surveys the testimony presented at the hearings and some recent actions taken by Congress and by the Reagan Administration on information issues.  相似文献   
28.
HIV infection is associated with lipid abnormalities in treatment naïve patients. CD4 count is used for monitoring the HIV infection. Primary objective was to evaluate and correlate lipid profile and CD4 counts in HIV infection. Secondary objective was to evaluate the feasibility of using Lipid profile to monitor the HIV infected treatment naïve patients instead of CD4 counts. 112 patients were selected based on a criteria from ART center in tertiary care center. CD4 counts were assessed and Lipid profile was evaluated enzymatically. A correlation study was done between the lipid profile and the CD4 count and clinical stages of infection. Cholesterol showed no significant correlation in any stage. HDL-C showed significant correlation (p < 0.05) with stage 2 and 4 disease. LDL-C showed no significant correlation in any stage. TGL showed significant correlation (p < 0.05) at stage 4 disease. Hence, HDL-C and TGL can be used as indicators of lipid status and for infection progression in treatment naive HIV patients, while Cholesterol and LDL-C has no role to play.  相似文献   
29.
Think it over     
S. Ravi 《Resonance》2000,5(12):75-75
  相似文献   
30.
This paper describes a research study which examined the degree to which the levels of English proficiency (high vs. low) and education (graduate vs. undergraduate) of students for whom English is a second language (ESL) were associated with differences in their reading behavior patterns. Subjects completed a survey which elicited information about several aspects of their reading behavior patterns including the type of materials read, the amount of time devoted to each type of reading, perceptions of their own reading ability, weaknesses, and needed improvements in reading. The results revealed that many of the mean scores obtained differed significantly, a fact indicating that the subjects’ levels of education and English proficiency were indeed associated with their reading behavior patterns. The paper concludes with a discussion of the instructional implications of the findings.  相似文献   
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