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101.
102.
Analysing the behaviour of student performance in classroom education is an active area in educational research. Early prediction of student performance may be helpful for both teacher and the student. However, the influencing factors of the student performance need to be identified first to build up such early prediction model. The existing data mining literature on student performance primarily focuses on student-related factors, though it may be influenced by many external factors also. Superior teaching acts as a catalyst which improves the knowledge dissemination process from teacher to the student. It also motivates the student to put more effort on the study. However, the research question, how the performance or grade correlates with teaching, is still relevant in present days. In this work, we propose a quantifiable measure of improvement with respect to the expected performance of a student. Furthermore, this study analyses the impact of teaching on performance improvement in theoretical courses of classroom-based education. It explores nearly 0.2 million academic records collected from an online system of an academic institute of national importance in India. The association mining approach has been adopted here and the result shows that confidence of both non-negative and positive improvements increase with superior teaching. This result indeed establishes the fact that teaching has a positive impact on student performance. To be more specific, the growing confidence of non-negative and positive improvements indicate that superior teaching facilitates more students to obtain either expected or better than expected grade.  相似文献   
103.
Systemic Lupus Erythematosus is an autoimmune disease with female preponderance. Anemia is found in 50% of Systemic Lupus Erythematosus patients. This is a cross sectional case control study with 30 female Systemic Lupus Erythematosus patients having inflammation associated anemia (Hemoglobin < 10.0 gm/dl) and 30 age matched controls with the aim to measure serum hepcidin and ferritin levels, correlate and study their role as homeostatic regulators of iron metabolism and utility as markers. Serum transferrin, ferritin, iron, total iron binding capacity, hsCRP, liver enzymes and renal parameters were analyzed by using automated analyser. Hepcidin levels were estimated by Sandwich-ELISA method. There was significant decrease in Iron (p < 0.0001), Iron Binding capacity (p < 0.0001), Transferrin (p < 0.0001) in patients, and a significant increase in inflammatory markers: hs-CRP (p < 0.0001), ESR (p < 0.0001) compared to controls. Significant increase in both Hepcidin (p < 0.0001) and Ferritin (p < 0.0001) was observed in patients with significant positive correlation (r = 0.711) with each other. Additionally, ferritin and hepcidin significantly positively correlated with hs-CRP and ESR (r = 0.526, 0.735); (r = 0.427, 0.742) respectively. Negative correlation with hemoglobin, iron, total iron binding capacity and transferrin with hepcidin (r = ? 0.80, ? 0.307, ? 0.553, ? 0.584) and ferritin (r = ?0.722, ? 0.22, ? 0.654, ? 0.728) was observed respectively. On ROC analysis both hepcidin and ferritin has sensitivity of 96.7%, specificity of 100% at cut-off values of 110 and 49 respectively. AUC of hepcidin was 0.993 and ferritin was 0.978. We have established a positive linear correlation between Hepcidin and Ferritin levels in disease activity and the changes correlated with the inflammatory state and anemia in patients, making them important mediators and potential markers of inflammation associated anemia.  相似文献   
104.
We investigated participants' ability to use internal representations of the environment to guide prehensile movements, when visual feedback was not available. Reaching and grasping performed with concurrent visual feedback was compared to conditions in which participants actively formed spatial images and passively encoded images from visual presented information. Movement times, the proportion of time spent after peak velocity and peak apertures, were greater when concurrent visual feedback was unavailable. Movement times increased as a function of premovement occlusion length, with passively encoded images resulting in shorter movement durations than actively formed images. The findings indicated that participants adapted their movement trajectories to compensate for the degradation of stored spatial information, when concurrent visual feedback was not available.  相似文献   
105.
Cappa C  Khan SM 《Child abuse & neglect》2011,35(12):1009-1021

Objectives

This article presents findings on caregivers’ attitudes towards physical punishment of children from 34 household surveys conducted in low- and middle-income countries in 2005 and 2006. The article analyzes the variability in attitudes by background characteristics of the respondents to examine whether various factors at the individual and family levels correlate with the caregivers’ beliefs in the need for violent discipline. The article also examines to what extent attitudes influence behaviors and compares groups of respondents to see how attitudes relate to disciplinary practices across caregivers of different socio-economic backgrounds.

Methods

The analysis is based on nationally representative data from 33 MICS and 1 DHS surveys. Questions on child discipline were addressed to the mother (or primary caregiver) of one randomly selected child aged 2–14 years in each household. The questionnaire asked whether any member of the household had used various violent and non-violent disciplinary practices with that child during the past month. Additionally, the interviewers asked the respondent if she believed that, in order to bring up that child properly, physical punishment was necessary. The sample included 166,635 mothers/primary caregivers.

Results

The analysis shows that, in most countries, the majority of mothers/primary caregivers did not think there was a need for physical punishment. Overall, characteristics such as household wealth and size, educational level and age, as well as place of residence were significantly associated with caregivers’ attitudes. The analysis confirms that beliefs influence disciplinary practices to a large degree: in all the countries but two, children were significantly more likely to experience physical punishment if their mothers/primary caregivers thought such punishment was needed. However, large proportions of children were found to be subject to physical punishment even if their mothers/primary caregivers did not consider this method necessary. This discrepancy between attitudes and behaviors is observed, although to different extents, in all the countries and across groups of mothers/primary caregivers with different levels of education and wealth.

Conclusions

The data presented in this article are among the few resources available to help develop a more global understanding of caregivers’ motivation in using violent discipline across a multitude of low- and middle-income countries. As such, the analysis of these data provides important insights for the development of effective strategies that will promote positive parenting practices. However, further data collection and analysis are needed to fully understand the reasons why physical punishment is used – even when caregivers do not think such method is necessary – opening the door for an even sharper programmatic response to change the practice.  相似文献   
106.

Background

Degenerative cervical myelopathy (DCM) is a recently proposed umbrella term for symptomatic cervical spinal cord compression secondary to degeneration of the spine. Currently literature searching for DCM is challenged by the inconsistent uptake of the term ‘DCM’ with many overlapping keywords and numerous synonyms.

Objectives

Here, we adapt our previous Ovid medline search filter for the Ovid embase database, to support comprehensive literature searching. Both embase and medline are recommended as a minimum for systematic reviews.

Methods

References contained within embase identified in our prior study formed a ‘development gold standard’ reference database (N = 220). The search filter was adapted for embase and checked against the reference database. The filter was then validated against the ‘validation gold standard’.

Results

A direct translation was not possible, as medline indexing for DCM and the keywords search field were not available in embase . We also used the ‘focus’ function to improve precision. The resulting search filter has 100% sensitivity in testing.

Discussion and Conclusion

We have developed a validated search filter capable of retrieving DCM references in embase with high sensitivity. In the absence of consistent terminology and indexing, this will support more efficient and robust evidence synthesis in the field.  相似文献   
107.
New Pedagogies on Teaching Science with Computer Simulations   总被引:1,自引:1,他引:0  
Teaching science with computer simulations is a complex undertaking. This case study examines how an experienced science teacher taught chemistry using computer simulations and the impact of his teaching on his students. Classroom observations over 3 semesters, teacher interviews, and student surveys were collected. The data was analyzed for (1) patterns in teacher-student-computer interactions, and (2) the outcome of these interactions on student learning. Using Technological Pedagogical Content Knowledge (TPCK) as a theoretical framework, analysis of the data indicates that computer simulations were employed in a unique instructional cycle across 11 topics in the science curriculum and that several teacher-developed heuristics were important to guiding the pedagogical approach. The teacher followed a pattern of “generate-evaluate-modify” (GEM) to teach chemistry, and simulation technology (T) was integrated in every stage of GEM (or T-GEM). Analysis of the student survey suggested that engagement with T-GEM enhanced conceptual understanding of chemistry. The author postulates the affordances of computer simulations and suggests T-GEM and its heuristics as an effective and viable pedagogy for teaching science with technology.  相似文献   
108.
Progress in diagnosis of infertility, has been dramatically increased during the past decades with changes occurring in virtually all aspects of infertility research, thus providing innovative diagnostic testing and sophisticated instrumentation for improved management and treatment of infertility. There are about 50% of infertile couples who are suffering because of male infertility. Semen examination is a basic investigation for these infertile couples. It not only reveals the quantity and quality of sperm but also the quality of the seminal plasma, which is essential for normal sperm function. In this review, the recent advancement in investigation procedures has been analyzed which are very important in clinical practice to (a) evaluate the sperm fertilizing ability (Acrosin, aniline blue, HOS), (b) characterization of male accessory sex glands secretions (Fructose, alpha-glucosidase, PSA) and (c) the management of azoospermic patients. It is believed that use of such diagnostic procedures will facilitate wide selection of patients for whom an effective therapy might be then possible.  相似文献   
109.
The development of vaccines to prevent infectious diseases has been one of the most important contributions of biomedical sciences. Increasing understanding in biochemistry, molecular biology, molecular genetics and related fields have provided an opportunity for the development of new generation vaccines that are based on rational design approaches. This is possible because of proper understanding of the microbial-genetics, biochemistry, host-pathogen interaction and recent developments in molecular immunology. Another important improvement made in the quality of vaccine production is the incorporation of immunomodulators or adjuvants with modified delivery vehicles viz liposomes, Iscoms and microspheres apart from alum being used as a gold standard. This article reviews the art of vaccination from Jenner period to present day context highlighting all the developments made at each stage of the vaccine development. Various criteria have been discussed regarding the selection of epitopes that expand B & T cells, its linkage with other accessory cells of the immune system, means to overcome MHC linked immune unresponsiveness, enhanced antigen processing and presentations that specially induce either helper or cytotoxic or mucosal immune responses were critically discussed.  相似文献   
110.
Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants (Caralluma acutangula, Rhazya stricta, and Moringa peregrina) and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp. (6 isolates), Alternaria sp. (2), Bipolaris sp. (1), and Cladosporium sp. (1) based on 18S rDNA sequencing and phylogenetic analysis. The culture filtrates (CFs; 25%, 50%, and 100% concentrations) from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF (100%) of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry (GC/MS) analysis showed the highest indole acetic acid content ((54.31±0.21) μmol/L) in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses.  相似文献   
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