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991.
Nychthemeral rhythmicity of urinary copper (Cu) was studied in 40 clinically healthy volunteers and 35 renal stone formers. A marked diurnal rhythm was noticed in urinary Cu levels in healthy subjects with maximum excretion at 0000 to 0600 hr followed by a progressive fall during the rest of the period reaching minimum between 1200 to 1800 hr in males and 0600 to 1200 hr in female volunteers. Similarly, all stone patients exhibited a definite rhythm in urinary Cu with significant amplitude and acrophases at 2145 hr for males and 2141 hr for female stone formers. However, there was no difference in mean 24-hr Cu excretion in male and female stone formers, whereas a significant change was observed in case of healthy subjects. Urinary Cu was found to be significantly increased in renal stone formers in comparison to healthy controls of either sex attributing a significant role of this overlooked trace mineral in the crystallization and/or activation of either of the process of stone formation in the renal tubules.  相似文献   
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Natural Language Processing (NLP) techniques have been successfully used to automatically extract information from unstructured text through a detailed analysis of their content, often to satisfy particular information needs. In this paper, an automatic concept map construction technique, Fuzzy Association Concept Mapping (FACM), is proposed for the conversion of abstracted short texts into concept maps. The approach consists of a linguistic module and a recommendation module. The linguistic module is a text mining method that does not require the use to have any prior knowledge about using NLP techniques. It incorporates rule-based reasoning (RBR) and case based reasoning (CBR) for anaphoric resolution. It aims at extracting the propositions in text so as to construct a concept map automatically. The recommendation module is arrived at by adopting fuzzy set theories. It is an interactive process which provides suggestions of propositions for further human refinement of the automatically generated concept maps. The suggested propositions are relationships among the concepts which are not explicitly found in the paragraphs. This technique helps to stimulate individual reflection and generate new knowledge. Evaluation was carried out by using the Science Citation Index (SCI) abstract database and CNET News as test data, which are well known databases and the quality of the text is assured. Experimental results show that the automatically generated concept maps conform to the outputs generated manually by domain experts, since the degree of difference between them is proportionally small. The method provides users with the ability to convert scientific and short texts into a structured format which can be easily processed by computer. Moreover, it provides knowledge workers with extra time to re-think their written text and to view their knowledge from another angle.  相似文献   
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We have developed a two-step electron-beam lithography process to fabricate a tandem array of three pairs of tip-like gold nanoelectronic detectors with electrode gap size as small as 9 nm, embedded in a coplanar fashion to 60 nm deep, 100 nm wide, and up to 150 μm long nanochannels coupled to a world-micro-nanofluidic interface for easy sample introduction. Experimental tests with a sealed device using DNA-protein complexes demonstrate the coplanarity of the nanoelectrodes to the nanochannel surface. Further, this device could improve transverse current detection by correlated time-of-flight measurements of translocating samples, and serve as an autocalibrated velocimeter and nanoscale tandem Coulter counters for single molecule analysis of heterogeneous samples.  相似文献   
997.
A report is given of the investigation of the iodine content of oyster shells taken from the reefs found in the Gulf of Mexico. The pulverized shells as sold on the market contain 200 to 300 parts per billion of iodine. Water soluble and alcohol soluble iodides appear to be absent. The granulated undried shells contain 500 parts per billion of iodine. Apparently there is a loss of iodine due to the temperature at which the pulverized shells are dried.  相似文献   
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Early childhood teacher educators frequently enhance their teaching by reading children’s books to their adult students. It is not unusual for faculty outside of early childhood to question devoting precious class time to read-alouds which they may consider a curious, if not frivolous, instructional strategy. Quality children’s literature can, however, enhance students’ experiences in the college classroom, contribute to their understanding of course content, promote their personal growth and self-understanding, increase their appreciation for quality children’s literature, and enhance their ability to integrate storybooks into their own teaching. Children’s books often capture a child’s point of view. They have the potential to provide historical or cultural perspectives on children and families. They also can lead to the examination of universal truths and can facilitate the discussion of sensitive or emotional issues A list of books with suggested uses is included.  相似文献   
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Tertiary Education and Management - In this article, we will argue that students played an important role at several crucial junctures of modern Czech history, which secured them a central position...  相似文献   
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