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131.
Cardiometabolic syndrome is one of the major public health issues of this century which describes a cluster of clinical characteristics. Seventy two patients with coronary artery disease (CAD) and cardiometabolic syndrome and forty healthy age and sex matched normal controls were selected for this study. Detailed clinical epidemiological and anthropometric characteristics were noted. Lipid profile and Cytokinesis-block micronuclei (CBMN) assay using cytochalasin B were carried out in all the subjects. Serum total cholesterol, triglyceride and LDL-cholesterol was significantly higher and HDL cholesterol was significantly lower in patients compared to their normal counter-parts (P<0.05). CBMN frequency of the patients was significantly higher at all ages compared to their normal counter parts (P<0.05). Various risk factors like diabetes, hypertension, dyslipidemia, abdominal obesity, smoking and alcoholism were found influenced the CBMN frequency; but the changes were not significant. From this study it can be concluded that DNA damage was found to be higher in patients with cardiometabolic syndrome which may be attributed to the generation of free radicals associated with alcohol consumption, tobacco use, dyslipidemia and glucose intolerance and the accumulation of free radicals with increase in age.  相似文献   
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In this study, we examined whether reward contrast influences choice between delayed and probabilistic outcomes. Specifically, we predicted that the subjective value of an intermediate reward would seem relatively larger or smaller, respectively, if it followed choices involving a smaller or larger reward and would produce corresponding changes in rates of delay and probability discounting. In Experiment 1, subjects made choices about hypothetical 5,000 or5,000 or 50 outcomes and then made choices about 500 outcomes. Delay-discounting rates for the500 outcomes. Delay-discounting rates for the 500 outcome were larger for Group 5,000 than for Group5,000 than for Group 50, whereas the opposite result was obtained for probability-discounting rates. In Experiment 2, we used a design that allowed for contrast effects to be assessed within subjects. Two groups made choices about delayed or probabilistic rewards. After completing question blocks in which the amount was 5,000 or5,000 or 50, subjects responded to questions with an intermediate amount (475/475/525). For Group Delay, the present value of the intermediate reward was greater after the 50 block than after the50 block than after the 5,000 block, whereas the opposite was obtained for Group Probability. The results from both experiments confirmed the predictions of reward contrast and suggested that the subjective value of a monetary reward varies inversely with the prior reward amount.  相似文献   
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While a number of studies have been conducted on the impact of online assessment and teaching methods on student learning, the field does not seem settled around the promised benefits of such approaches. It is argued that the reason for this state of affairs is that few studies have been able to control for a number of confounding factors in student performance. We report on the introduction of a regular (every 3 weeks) low-mark online assessment tool in a large, first-year business mathematics course at the University of New South Wales, a major Australian university. Using a retrospective regression methodology together with a very large and rich data set, we test the proposition that exposure to the online assessment instrument enhances student learning. Significantly, we are able to control for prior student aptitude, in-course mastery, gender and even effort via a voluntary class attendance proxy. Furthermore, the study incorporates two large, and statistically diverse cohorts as well as manipulations in the model tested to robustly examine the outcomes. Our central result is that higher exposure to the online instrument robustly leads to higher student learning, all else being equal. Various implications for online assessment design, implementation and targeting are also discussed.  相似文献   
136.
This paper reports research from a three-year Australian science teacher professional learning project, the Science Teaching and Learning (STaL) Project, in which groups of science teacher participants (across years K – 12) worked with academics over a one-year period as teacher researchers. Through reflecting on their experiences within the STaL Project and collecting data from their classrooms related to specific science teaching concerns, teacher participants constructed cases around particular aspects of their professional learning. The cases that these participants developed elicited rich insights into their teaching and their students’ learning of science. This paper discusses how the cases were developed by the teacher researcher participants and uses exemplars as a way of illustrating the nature of the professional knowledge developed.  相似文献   
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This paper examines the theories of organisation that have informed our understanding of schools as complex social worlds and the practice of school leadership that seems to be required in such environments. This understanding has, in turn, determined the research approach we have adopted for investigating principals’ work and for ascertaining the utility of existing approaches to their initial preparation. The paper argues that the extent to which preparation processes align with principals’ professional needs will depend on the extent to which they are able to connect with the realities of workplaces found in schools as well as the environments in which they are located. For this purpose, it is desirable to pursue the kind of enquiry that is capable of revealing what schools leaders know and brings them to a new stage in their thinking about practice.  相似文献   
139.
Double-block instruction has become a popular strategy for supporting struggling mathematics students in algebra I. Despite its widespread adoption, little consistent evidence supports the attributes of a successful double-block design or the effectiveness of this instructional strategy. In this study, the authors examine a pilot implementation of a double-block strategy—instantiated in the program Intensified Algebra—that combines core algebra content with insights from research on how students learn mathematics and explicit noncognitive supports focused on key attitudes, beliefs, and behaviors essential to student success. The results of the study show that, when implemented with fidelity, participation in the program significantly increased student achievement on the state end-of-course algebra I assessment.  相似文献   
140.
Acoustic trapping of minute bead amounts against fluid flow allows for easy automation of multiple assay steps, using a convenient aspirate/dispense format. Here, a method based on acoustic trapping that allows sample preparation for immuno-matrix-assisted laser desorption/ionization mass spectrometry using only half a million 2.8 μm antibody covered beads is presented. The acoustic trapping is done in 200 × 2000 μm2 glass capillaries and provides highly efficient binding and washing conditions, as shown by complete removal of detergents and sample processing times of 5-10 min. The versatility of the method is demonstrated using an antibody against Angiotensin I (Ang I), a peptide hormone involved in hypotension. Using this model system, the acoustic trapping was efficient in enriching Angiotensin at 400 pM spiked in plasma samples.  相似文献   
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