Query expansion is a widely studied technique for improving information retrieval effectiveness. In this paper we proposed a new query expansion technique using the comprehensive thesaurus WordNet and its semantic relatedness measure modules. Word sense disambiguation are performed on original query sentence, yielding the concept of each term in the query. Based on those recovered concepts, expanded query terms are generated from WordNet lexical database. The proposed method has been evaluated in document retrieval on the Web using query sentence. Our extensive experimental results demonstrate a 7% precision improvement over retrieval methods not employing query expansion techniques.

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Human blood specimens serve as important research materials in the field of translational medicine research. The RNA extracted from blood, for example, represents the gene expression profiles of individuals or groups, and can be indicative of the pathological basis for human diseases. Meanwhile, the RNA quality may have severe impacts on the results of RNA studies. RNA is susceptible to many factors, such as the time of sample collection, transportation conditions, protectants, pretreatments, and extraction methods. In this study, six different pretreatment methods are evaluated for their effects on blood RNA extraction including the RNA yields and quality. Results show that most of these methods meet the basic requirements for RNA studies. While considering the simplicity of the procedure, the cost factor, and how to make full use of the samples, the proper method should be employed by researchers who have specific requirements for their research.

In the environments of various open coal storage sites, mining-affected coalbeds, and goafs, etc., some coal bodies are often affected by external environmental factors. They are highly prone to spontaneous combustion in low moisture content (≤8%). In order to examine the effect of low moisture content on the spontaneous combustion tendency of coals with different metamorphic grade, we conducted a temperature programmed oxidation (TPO) experiment and differential scanning calorimetry (DSC) experiment to study the spontaneous combustion characteristics of coals with different metamorphic grade at four different low moisture contents. The change laws of the characteristic parameters of four different metamorphic grade coals at four different low moisture contents were comparatively analyzed. The experimental results indicate that: (1) Compared other low moisture content, anthracite and fat coal at a low moisture content of 1.2 % show a stronger tendency for spontaneous combustion, and long flame coal and lignite at a low moisture content of 3.4% and 5.6% are more prone to spontaneous combustion. (2) Four different metamorphic grade coals at a low moisture content of 7.8% are less prone to spontaneous combustion.