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81.
Rank Aggregation techniques have found wide applications for metasearch along with other streams such as Sports, Voting System, Stock Markets, and Reduction in Spam. This paper presents the optimization of rank lists for web queries put by the user on different MetaSearch engines. A metaheuristic approach such as Genetic algorithm based rank aggregation technique has been proposed and implemented in MATLAB for Kendall-tau as (GKTu) and Spearman’s foot rule as (GSFD) distance measures. A comparative analysis has been carried out between ranked lists for with and without GA on the basis of simulated results. From the results it has been found that proposed GA optimized rank list (for a particular query on the basis of minimum distance) is better than the conventional methods. In addition, a word association technique i.e., AND-OR operator has been applied on each query. The results are investigated in comparison to non- logic operators for the same query.  相似文献   
82.
Genome-wide association studies have discovered multiple single nucleotide polymorphisms (SNPs) associated with the risk of common diseases. The objective of this study was to demonstrate the replication of previously published SNPs that showed statistical significance for breast cancer in the Malaysian population. In this case–control study, 80 subjects for each group were recruited from various hospitals in Malaysia. A total of 768 SNPs were genotyped and analyzed to distinguish risk and protective alleles. A total of three SNPs were found to be associated with increased risk of breast cancer while six SNPs showed protective effect. All nine were statistically significant SNPs (p ≤ 0.01), five SNPs from previous studies were successfully replicated in our study. Significant modifiable (diet) and non-modifiable (family history of breast cancer in first degree relative) risk factors were also observed. We identified nine SNPs from this study to be either conferring susceptibility or protection to breast cancer which may serve as potential markers in risk prediction.

Electronic supplementary material

The online version of this article (doi:10.1007/s12291-013-0414-0) contains supplementary material, which is available to authorized users.  相似文献   
83.
Despite enormous research in the field of hypertension, its pathophysiology still remains largely unresolved and appears to be multifactorial. In the present communication, we have analyzed the status of nitric oxide (NO) in the patients with essential hypertension and age matched controls. We have found that the levels of NO are lowered in essential hypertension. The normalization of blood pressure by administration of antihypertensive therapy causes rise in the NO level indicating that perturbed NO status in essential hypertension is reversible. Addition of antioxidant to the antihypertensive drugs causes a further, though non significant, rise in the levels of NO, suggesting that antioxidants may be combined with antihypertensive drugs as adjunct in the management of essential hypertension.  相似文献   
84.
Education and Information Technologies - The rapid changes in recent years witnessed the development of technology-based education environment where teachers and learners can interact by adopting...  相似文献   
85.
Currently, world is facing a global outbreak causing a pandemic threat known as COVID-19. This infectious disease is triggered by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Gut microbiota harbours multi species community with a strong impact on host immune homeostasis. However, our knowledge about this gut microbiota and its symbiotic relationship with immune activation in association with SARS-CoV-2 is limited. Unbalanced bacterial flora with too many opportunistic infections can shift immune system towards a cascade of inflammatory responses leading to multi organ damage. This review will highlight immune-regulation via various mechanisms in SARS-CoV-2 infection. Diet has an unbelievable influence on gut microbiome that allows a new state of homeostasis to be reached through timing, frequency and duration of intake. This review article focuses on gut, lung microbiota and immunomodulation with specific attention on immune activation by gut microbiota.  相似文献   
86.
This paper is a report of a study on early school experience as part of a Teacher Education programme in Turkey. The programme requires second-year students to act as students only, observing their mentors in classrooms rather than practising teaching so that they can gain a wider view of the teaching profession. The study analyses the experiences of these students, therefore, particularly focusing on the extent to which this scheme is conducive to making students learn from their experience. The findings from the qualitative data suggest that careful attention must be paid to major factors shaping this process, such as the school atmosphere as a whole, the nature of tasks for observation, the quality of interaction between student-mentor, and, more importantly, the opportunities for students to develop an inquiry-based approach to teaching.  相似文献   
87.
This study, employing hierarchical linear modeling (HLM), sought to investigate the student-level and school-level factors associated with the science achievement of immigrant and non-immigrant students among a national sample of 22,646 students from 896 schools in Canada. While student background characteristics such as home language, family wealth, and socioeconomic status were significant predictors of science achievement for non-immigrant students, these factors were not significantly associated with immigrant student science achievement. Student attitudes, engagement, and motivation in science and information and communication technology familiarity were significant predictors of science achievement for both immigrant and non-immigrant students. Whereas teacher shortage was associated with science achievement for immigrant students, school size was associated with science achievement for non-immigrant students. Implications of the findings are discussed.  相似文献   
88.
The Taubman Health Sciences Library (THL) is integrated in all four years of the University of Michigan Medical School (UMMS) curriculum. Information resources are introduced at strategic points throughout the curriculum so that students receive training at times when they are most likely to need the resource. Most of the core instruction sessions are taught in teams that consist of librarians and UMMS faculty, which provides unique learning opportunities for students. This article describes each THL instruction activity in the four-year undergraduate UMMS curriculum and provides commentary on the overall effectiveness of this integrated approach to instruction.  相似文献   
89.
Background:?Students’ motivation is known to influence academic outcomes. However, there is a paucity of research showing the relative influences of motivational factors on short-term and long-term outcomes.

Purpose:?The study investigates the relative influences of motivational factors – mastery goal orientation, value of schooling, and academic self-concepts (perceived competence in and affect to schoolwork) on four outcomes – rule acceptance, identity, general self-efficacy and achievement.

Sample:?Students in grades 3 to 6 from six primary schools in the Sydney were surveyed (N = 979). The ages of the participants varied from 8 to 13 years (mean = 9.78).

Design and methods:?Students completed a questionnaire and literacy and numeracy achievement tests. Structural equation modelling was used to examine the paths from four predictors to four outcomes.

Results:?Whereas all four predictors were positively associated with all four outcomes, students’ mastery goal had stronger positive influences on self-efficacy and identity. Value, perceived competence and affect were found to influence outcomes in different ways – positive influences were found for value on achievement, rule-acceptance, and identity; for perceived competence on achievement and efficacy; and for affect on rule-acceptance and identity.

Conclusion:?Mastery goal had stronger influences on long-term outcomes while other predictors are stronger for short-term outcomes. To facilitate short-term and long-term outcomes, all four motivational factors need attention.  相似文献   
90.
The study was planned to assess the prevalence of thyroid disorders in type 2 diabetes in North Indian population and to correlate the serum insulin and glycosylated haemoglobin levels with thyroid hormones. It is a case control study. One hundred and twenty patients of type 2 diabetes were included in the study along with 117 adults of the same age group and normal glucose levels as controls. All blood samples were taken from subjects who fasted for at least 12 h before the blood collection. Glycosylated hemoglobin was determined by ion exchange chromatography and serum insulin and thyroid hormones were assessed through enzyme linked immunosorbent assay. Fasting blood glucose and glycosylated haemoglobin levels were significantly higher in diabetics showing a poor glucose control. Serum tri-iodothyronine values were significantly lower in diabetics. There was a significant correlation between glycosylated haemoglobin and thyroid hormones. There was no correlation between serum insulin and thyroid hormones.  相似文献   
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