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991.
992.
This paper explores the application of term dependency in information retrieval (IR) and proposes a novel dependency retrieval model. This retrieval model suggests an extension to the existing language modeling (LM) approach to IR by introducing dependency models for both query and document. Relevance between document and query is then evaluated by reference to the Kullback-Leibler divergence between their dependency models. This paper introduces a novel hybrid dependency structure, which allows integration of various forms of dependency within a single framework. A pseudo relevance feedback based method is also introduced for constructing query dependency model. The basic idea is to use query-relevant top-ranking sentences extracted from the top documents at retrieval time as the augmented representation of query, from which the relationships between query terms are identified. A Markov Random Field (MRF) based approach is presented to ensure the relevance of the extracted sentences, which utilizes the association features between query terms within a sentence to evaluate the relevance of each sentence. This dependency retrieval model was compared with other traditional retrieval models. Experiments indicated that it produces significant improvements in retrieval effectiveness.  相似文献   
993.
Developments in society and business, and related changes in higher education and lifelong learning, require educators and educational designers or technologists to rethink education. Examples of such changes are the growing importance of achieving complex learning, the integration of learning and work in education, and the need for improved flexibility with regard to time, place, and individual needs. These changes cannot simply be responded to by adding technological solutions implemented according to existing educational approaches. Instead, an integrated view of e-learning is necessary, characterized by the combination of pedagogical, technical, social, and organizational factors. This two-part special issue elaborates on the different characteristics of integrated e-learning, from design through future topics for research. He would like to give special thanks to Jan Elen and Brent Wilson, who took on the task of reviewing and discussing all of the contributions, both at AECT 2003 in Anaheim and for this issue, and J. Michael Spector, Development Editor of this journal, for his faith in all of us.  相似文献   
994.
Several reasons for the modest relation between interest congruence and occupational outcomes are discussed, but focus is placed on possible moderators of this relation. Specifically individual differences, environmental differences and time are proposed as potential moderators. Overall, it is important to investigate theoretically driven moderators of the congruence-outcome relation to further our knowledge of this area.  相似文献   
995.
Distributed education delivered via the Internet is a growing practice, with most institutions offering at least course websites and many expanding to full course offerings and even online degree progams. There are two schools of thought with regard to delivery mode: the larger group has focused on asynchronous delivery, accessible at any time via webpages and interactive tutorials and quizzes, while a smaller group advocates synchronous delivery where students are online and interact during class time. This paper summarizes the advantages and disadvantages of the two delivery modes and describes our successful and growing experience of more than a decade using an open source synchronous delivery tool blended with a variety of asynchronous capabilities and classroom instruction. We conclude that a synergistic combination of the two modes with in-person instruction, designed to provide maximum flexibility to the student within the constraints of the subject, offers the best support for student learning. www:  相似文献   
996.
Resource allocation and funding in higher education is crucial to the success of reform and transformation of our higher education system. With a view to identifying trends and best practices in the area, utilizing a method of systematic literature review, we have critically reviewed relevant theories and practices from developed counties that are covered in the scholarly literature published in English in the past 10 years. Our review has revealed: (1) Several universal trends have exerted a decisive impact on resource allocation in higher education, for example, funding reduction and tuition fee increases, performancebased funding, privatization, corporatization, and internationalization; (2) Several theories underpin key research in the area, for example, new institutional economics, resource dependence theory, and political economy; (3) Several controversial issues have made their way into public debate, for example, higher education as a public good or private good, academic capitalism, educational equity, and the role of econometrics.  相似文献   
997.
998.
To investigate dietary protein level effects on digestive mechanisms, weaned piglets were fed for 45 d with diets containing 20%, 17%, or 14% crude protein (CP) supplemented to meet requirements for essential amino acids. This article describes the influence of dietary protein on gastrointestinal hormones and expression of an array of digestive enzymes in the gastrointestinal tract and pancreas. Results indicated that there were no significant differences in expression of enzymes involved in carbohydrate digestion, except for maltase in the duodenum. In the jejunum, amylase expression in pigs fed 20% CP was much higher than that in pigs fed other diets (P<0.05) and maltase expression in those fed 17% CP was higher than that in other treatments (P<0.05). Although there were no remarkable differences in expression of aminopeptidase in the small intestine or carboxypeptidase in the pancreas (P>0.05), there was a trend towards higher expression of various proteases in pigs fed 17% CP. The duodenal expression of enteropeptidase in diets with 14% and 17% CP was significantly higher than that with 20% CP (P<0.05), but treatment differences did not existed in jejunum (P>0.05). The expression of GPR93 as a nutrient-responsive G protein-coupled receptor in 14% and 17% CP diets was significantly higher than that in 20% CP diet in the small intestine (P<0.05). The expressions of genes for pancreatic enzymes, lipase and elastase, were significantly higher in pigs fed diets with low CP, while similar trends occurred for carboxypeptidase, chymotrypsin and amylase. Conversely, the gastric expressions of pepsinogen A and progastricsin were lower with the 17% CP diet. Differences between treatments were found in the gastric antral contents of cholecystokinin and somatostatin: both increased in pigs fed 17% CP, accompanied by decreased content of motilin, which was also seen in plasma concentrations. These patterns were not reflected in duodenal contents. In general, 17% dietary CP was beneficial to the digestion of nutrient substance in the gastrointestinal tract.  相似文献   
999.
There are child soldiers fighting with government forces and opposition groups in more than 30 countries worldwide. Although studies have been conducted on the impact of war-related trauma on children, very few have focused on those children who do not exhibit trauma-related symptoms after experiencing armed combat. The purpose of this study was to identify and understand some of the mechanisms and resources that resilient children draw upon to overcome the trauma of child soldiering. Six Colombian child soldiers were recruited through purposive sampling techniques to participate in a narrative study focusing on their lived experiences and their personal understanding of how they were able to overcome the effects of war trauma. Six narrative themes were identified and discussed in terms of the literature on trauma and childhood resilience and also related to counselling needs and services.  相似文献   
1000.
This study investigated the alleviating effects of hydrogen sulfide (H2S), derived from sodium hydrosulfide (NaHS), on inflammation induced by dextran sulfate sodium (DSS) in both in vivo and in vitro models. We found that NaHS injection markedly decreased rectal bleeding, diarrhea, and histological injury in DSS-challenged mice. NaHS (20 µmol/L) reversed DSS-induced inhibition in cell viability in Caco-2 cells and alleviated pro-inflammation cytokine expression in vivo and in vitro, indicating an anti-inflammatory function for H2S. It was also found that H2S may regulate cytokine expression by inhibiting the nuclear factor-κB (NF-κB) signaling pathway. In conclusion, our results demonstrated that H2S alleviated DSS-induced inflammation in vivo and in vitro and that the signal mechanism might be associated with the NF-κB signaling pathway.  相似文献   
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