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This paper describes the ways that students’ problem-solving behaviors evolve when solving multi-faceted, context-rich problems within a web-based learning environment. During the semester, groups of two or three students worked on five physics problems that required drawing on more than one concept and, hence, could not be readily solved with simple “plug-and-chug” strategies. The problems were presented to students in a data-rich, online problem-based learning environment that tracked which information items were selected by students as they attempted to solve the problem. The students also completed a variety of tasks, like entering an initial qualitative analysis of the problem into an online form. Students were not constrained to complete these tasks in any specific order. As they gained more experience in solving context-rich physics problems, student groups showed some progression towards expert-like behavior as they completed qualitative analysis earlier and were more selective in their perusal of informational resources. However, there was room for more improvement as approximately half of the groups still completed the qualitative analysis task towards the end of the problem-solving process rather than at the beginning of the task when it would have been most useful to their work.  相似文献   
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Indian ethnicity by itself is a strong risk factor for development of CAD in Indian postmenopausal women due to lower HDL levels as compared to Whites and women of oriental origin. We evaluated and compared the short-term effects of menopause, estrogen replacement therapy and combined estrogen and progestin replacement therapy on various atherogenic indices. 40 postmenopausal women, both surgical and natural (20 each) were selected. 10 surgical postmenopausal women were given 0.625 mg conjugated estrogens daily for 6 months and 10 natural postmenopausal women were given 0.625 mg conjugated estrogen with 2.5 mg medroxyprogesterone acetate daily. 20 women were included in the control group and given placebo. Fasting venous blood samples were analyzed for extended lipid profile and calculated atherogenic indices before starting the therapy and after 1,3 and 6 months. LDL and Apolipoprotein B increased (p<0.05) and those of Apolipoprotein A1 and HDL decreased in the control groups. In both the study groups levels of serum cholesterol and LDL decreased (p<0.05) and those of HDL and Apolipoprotein A1 increased (p<0.01). LDL/HDL, Apo B/ApoA1, Total Cholesterol/HDL decreased significantly (p<0.05) in both the study groups compared to the control groups. The effect of estrogen alone was more significant as compared to combination therapy. Log Triglycerides (TG)/HDL ratio showed a decrease in women on estrogen alone but the difference was not significant. Our study confirms that short term HRT has a favorable effect on atherogenic indices in Indian postmenopausal women.  相似文献   
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Colostrum, the mammary secretion during first 2–4 days of lactation, provides all the essential components of nutrition and passive immunity required by the newborn. Pregnancy induced hypertension (PIH), glucose intolerance and anaemia are common medical complications observed during pregnancy in Indian women and their effects were studied on the composition of colostrum collected within 24 hours of delivery from lactating women included in the study. PIH during pregnancy significantly decreased colostrum IgA and total proteins, but showed a significant increase in K+ levels, where as women with glucose intolerance showed a significant decrease in total lipids and lactose and an increase in Na+ levels in colostrum compared to normal controls. The group with anaemia also showed a significant decrease in colostrum IgA and total protein levels when compared with the control group. Awareness about the changes that occur in the composition of colostrum during complicated pregnancies can be an important and useful tool for preventive and protective paediatrics.  相似文献   
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The effect of 40 days yoga training in 30 hospitalized non-insulin dependent diabetes mellitus (NIDDM) patients has been investigated after stopping the medication. Blood glucose response to oral glucose load measured as area index total (AIT), glycated haemoglobin (GHb) plasma lipids and lipoproteins measurements before and after yoga training have been compared. Yoga training resulted in a significant improvement in AIT, GHb and plasma triglycerides and cholesterol levels. The data suggest that yoga training along with diet and medical management provides an important metabolic control in NIDDM and may have a role in primary prevention of diabetes mellitus.  相似文献   
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We present design, characterization, and testing of an inexpensive, sheath-flow based microfluidic device for three-dimensional (3D) hydrodynamic focusing of cells in imaging flow cytometry. In contrast to other 3D sheathing devices, our device hydrodynamically focuses the cells in a single-file near the bottom wall of the microchannel that allows imaging cells with high magnification and low working distance objectives, without the need for small device dimensions. The relatively large dimensions of the microchannels enable easy fabrication using less-precise fabrication techniques, and the simplicity of the device design avoids the need for tedious alignment of various layers. We have characterized the performance of the device with 3D numerical simulations and validated these simulations with experiments of hydrodynamic focusing of a fluorescently dyed sample fluid. The simulations show that the width and the height of the 3D focused sample stream can be controlled independently by varying the heights of main and side channels of the device, and the flow rates of sample and sheath fluids. Based on simulations, we also provide useful guidelines for choosing the device dimensions and flow rates for focusing cells of a particular size. Thereafter, we demonstrate the applicability of our device for imaging a large number of RBCs using brightfield microscopy. We also discuss the choice of the region of interest and camera frame rate so as to image each cell individually in our device. The design of our microfluidic device makes it equally applicable for imaging cells of different sizes using various other imaging techniques such as phase-contrast and fluorescence microscopy.  相似文献   
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Recent technological advancements in data storage and processing have changed how companies conduct their business. An increasing number of firms have started putting their efforts in extracting information from their databases to improve profitability and reduce costs using quantitative approaches. Thus, the job market has been experiencing a rapidly growing demand for business analytics (BA) practitioners, and universities across the globe are increasingly responding to this newly emerged field by offering both undergraduate and graduate level degrees as well as certificate programs. Thus, this research aims to provide a framework for academic institutions to develop a state‐of‐the‐art master's in business analytics (MSBA) curriculum by identifying concepts, skills, knowledge, and tools (CSKT) that industry seeks in BA practitioners. Our data‐driven methodology utilizes peer institution analysis, indeed.com web scraping, and focus group analysis with mid‐ and senior‐level analytics leaders from major companies. Our contribution to the literature and recommendations to institutions developing MSBA programs are offered at the end.  相似文献   
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