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The Landau theory of phase transitions occupies a centerpiece position in physics. We illustrate the theory by a pedagogical example at the pre-university level. In the example a bead of mass is threaded on a ring which is set rotating about a vertical diameter. The dynamics of the bead mimics key features of the Landau theory.  相似文献   
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Advances in instrument technology and automation have simplified tasks in laboratory diagnostics reducing errors during analysis thereby improving the quality of test results. However studies show that most laboratory errors occur in the pre-analytical phase. In view of the paucity of studies examining pre-analytical errors, we examined a total of 1513 request forms received at our laboratory during a 3 month period. The forms were scrutinized for the presence of specific parameters to assess the pre-analytical errors affecting the laboratory results. No diagnosis was provided on 61.20% of forms. Type of specimen was not mentioned in 61.60% of the forms and 89.25% of all forms were illegible. Critical results were encountered in 17.30% of patients, and of these 76.60% were not communicated due to incomplete forms. Thus, by following standard operating procedures vigorously from patient preparation to sample processing the laboratory results can be significantly improved without any extra cost.  相似文献   
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Protein hydrolysates are good nutritional supplements as their bioactive ingredients can be easily absorbed and utilized for various metabolic activities. A fish protein hydrolysate (Amizate), prepared by a unique process of hydrolysis has the advantage of high di/tri peptide content (<10 kDa) along with essential and non essential amino acids, micronutrients and vitamins. The effect of Amizate on malnourished children (6–8 years, a total of 438) of Grade I and II (Gomez’s classification) with respect to immunoglobulins, CD4/CD8 ratios and hemoglobin was examined. Measurement of these parameters during the user trial study (at the beginning and the end after 4 months) indicated that the levels of the immunological parameters were not significantly altered by the Amizate treatment. The values of immunoglobulins and CD4/CD8 ratios of malnourished children (India) are in the normal range and are in accordance with the reported values of various ethnic groups.  相似文献   
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This paper presents an excerpt from a comprehensive study on the concepts of long-term athlete development. Following a qualitative research methodology and using a hermeneutic-reconstructive procedure the purpose of this paper was to gain insight into expert youth sports coaches’ understanding of the two main trajectories leading to elite performance: early specialization and early sampling. Analysis of the transcribed interviews suggests that the training strategy is primarily the result of a complex decision making process. Additionally, coaches perceived a trend towards early specialization which conflicts with existing considerations of long-term athlete development. The results of this study provide an opportunity to understand the subject of diversification in youth sports and to raise awareness for the problems of practitioners.  相似文献   
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