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1.
In Information Retrieval, since it is hard to identify users’ information needs, many approaches have been tried to solve this problem by expanding initial queries and reweighting the terms in the expanded queries using users’ relevance judgments. Although relevance feedback is most effective when relevance information about retrieved documents is provided by users, it is not always available. Another solution is to use correlated terms for query expansion. The main problem with this approach is how to construct the term-term correlations that can be used effectively to improve retrieval performance. In this study, we try to construct query concepts that denote users’ information needs from a document space, rather than to reformulate initial queries using the term correlations and/or users’ relevance feedback. To form query concepts, we extract features from each document, and then cluster the features into primitive concepts that are then used to form query concepts. Experiments are performed on the Associated Press (AP) dataset taken from the TREC collection. The experimental evaluation shows that our proposed framework called QCM (Query Concept Method) outperforms baseline probabilistic retrieval model on TREC retrieval.  相似文献   
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Very few empirical studies have investigated programmes in which doctoral students act as peer facilitators in faculty writing groups. We report on the development of a centrally delivered doctoral student writing programme in which twenty student participants were mentored and provided with the resources to initiate their own faculty-based doctoral writing groups. ‘Legitimate peripheral participation’ was used as a conceptual lens to interpret the data collected during the establishment and evaluation of the programme. All student participants in the preparatory training course, which was developed in consultation with postgraduate students and research supervisors, went on to become doctoral writing peer facilitators of peer writing groups. Insights from seven of these showed how a well-structured and supportive programme harnessed the benefits of peer learning by bringing personal rewards to participants and building institutional capacity around doctoral research writing literacies.  相似文献   
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Classroom     
In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. Wemay suggest strategies for dealingwith them, or invite responses, or both. “Classroom” is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science.  相似文献   
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Pleurotus sajor-caju (Fr.) Singer was cultivated on selected agro wastes viz. cotton stalks, groundnut haulms, soybean straw, pigeon pea stalks and leaves and wheat straw, alone or in combinations. Cotton stalks, pigeon pea stalks and wheat straw alone or in combination were found to be more suitable than groundnut haulms and soybean straw for the cultivation. Organic supplements such as groundnut oilseed cake, gram powder and rice bran not only affected growth parameters but also increased yields. Thus bioconversion of lignocellulosic biomass by P. sajor-caju offers a promising way to convert low quality biomass into an improved human food.  相似文献   
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The present work was aimed to study the association of one carbon genetic variants, hyperhomocysteinemia and oxidative stress markers, i.e., serum nitrite, plasma malondialdehyde (MDA) and glutathione (GSH) on intimal medial thickening (IMT) in patients with type 2 diabetes mellitus (T2D). A total number of 76 subjects from ACS Medical College and Hospital, Chennai, India were included in the study, i.e., Group I (n = 42) of T2D and Group II (n = 34) of age- and sex matched healthy controls. The glycated haemoglobin was measured by ion-exchange resin method; plasma homocysteine by Enzyme Linked Immunosorbant Assay method; serum nitrite (nitric oxide, NO), plasma MDA and GSH by spectrophotometric methods; the IMT by high frequency ultrasound. The polymorphisms of one carbon genetic variants were genotyped using polymerase chain reaction-restriction fragment length polymorphism and amplified fragment length polymorphism methods. Results indicate that methyltetrahydrofolate homocysteine methyl transferase (MTR) A2756G allele was found to be protective in T2D and the other variants were not significantly associated with T2D. Glutamate carboxypeptidase II (GCP II) C1561T (r = 0.34; p = 0.05) and methylene tetrahydrofolate reductase (MTHFR) C677T (r = 0.35; 0.04) showed positive correlation with plasma homocysteine in T2D cases. In this study, MTR A2756G allele was found to be protective in T2D; GCP II C1561T and MTHFR C677T showed positive association with plasma homocysteine in T2D cases. Among all the genetic variants, MTR A2756G was found influence IMT. RFC 1 G80A and TYMS 5′-UTR 2R3R showed synergistically interact with MTR A2756G in influencing increase in IMT.  相似文献   
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An extended model based on the theory of planned behaviour (TPB) was used to study Chinese English as a foreign language (EFL) students’ in-class participation. The model included the core TPB constructs (behavioural intentions, attitudes, subjective norms, and perceived behavioural control/self-efficacy) and 2 additional constructs (foreign language classroom anxiety and face-saving) frequently discussed in the literature about Chinese EFL classroom dynamics. A total of 199 Chinese students enrolled in a Sino-American international branch campus were surveyed. The results of a partial least squares (PLS) path modelling analysis revealed that attitudes, subjective norms, perceived behavioural control/self-efficacy, and face-saving explained 46% of the variance in intentions to participate in English in class. Perceived behavioural control/self-efficacy fully mediated the negative indirect effect of foreign language classroom anxiety on intentions. Pedagogical implications and future directions are discussed for implementation purposes.  相似文献   
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We report a case of a diabetic, heterozygote with near normal hematology, marginally low level of hemoglobin A2(HbA2) having an increased level of hemoglobin F(HbF) that was pancellularly distributed among the red cells. BioRad DiaSTAT measurements gave a high glycated hemoglobin A1c(HbA1c) of 31.5% and the BioRad Variant analyzer recorded an HbA1c value which was very low, in discordance with the detected blood glucose levels. Flow cytometry and polymerization chain reaction (PCR) based studies were carried out which revealed the case to be that of the common hereditary persistence of fetal hemoglobin (HPFH)-3, an Asian Indian mutation. Fructosamine estimation and HbA1c by Boronate affinity chromatography were able to resolve the discordant value detected and was able to confirm the diabetes status. The case would have been a diagnostic dilemma, if reported without correlation.  相似文献   
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