Fatty acid profiles of muscle from large yellow croaker (Pseudosciaena crocea R.) of different age     

Hong-gang TANG  Li-hong CHEN  Chao-geng XIAO  Tian-xing WU 《Journal of Zhejiang University. Science. B》2009,10(2)

We investigated the fatty acid profiles of muscle from large yellow croaker (Pseudosciaena crocea R.) of different age.One- and two-year-old fish were cultured in floating net cages and sampled randomly for analysis.Moisture,protein,lipid and ash contents were determined by methods of Association of Analytical Chemist (AOAC) International.Fatty acid profile was determined by gas chromatography.Crude protein,fat,moisture and ash contents showed no significant differences between the two age groups.The contents of total polyunsaturated fatty acids and docosahexaenoic acid (DHA) were significantly higher and eicosapentaenoic acid (EPA) content was significantly lower in the two-year-old large yellow croaker than in the one-year-old (P<0.05).No significant differences were observed in the contents of total saturated fatty acids and monounsaturated fatty acids,or the ratio of n-3/n-6 fatty acids among the large yellow croakers of the two age groups.We conclude that large yellow croakers are good food sources of EPA and DHA.  相似文献   

Fatty acid profiles of muscle from large yellow croaker (Pseudosciaena crocea R.) of different age     

Hong-gang Tang  Li-hong Chen  Chao-geng Xiao  Tian-xing Wu 《Journal of Zhejiang University. Science. B》2009,10(2):154-158

We investigated the fatty acid profiles of muscle from large yellow croaker (Pseudosciaena crocea R.) of different age. One- and two-year-old fish were cultured in floating net cages and sampled randomly for analysis. Moisture, protein, lipid and ash contents were determined by methods of Association of Analytical Chemist (AOAC) International. Fatty acid profile was determined by gas chromatography. Crude protein, fat, moisture and ash contents showed no significant differences between the two age groups. The contents of total polyunsaturated fatty acids and docosahexaenoic acid (DHA) were significantly higher and eicosapentaenoic acid (EPA) content was significantly lower in the two-year-old large yellow croaker than in the one-year-old (P<0.05). No significant differences were observed in the contents of total saturated fatty acids and monounsaturated fatty acids, or the ratio of n-3/n-6 fatty acids among the large yellow croakers of the two age groups. We conclude that large yellow croakers are good food sources of EPA and DHA.   相似文献   

外语专业大班教学问题与对策   总被引：1，自引：0，他引：1  

兰月秋 《高教论坛》2004,(5):122-125

由于高校扩招,外语专业大班型教学越来越普遍,带来了一系列的新问题和挑战。针对大班教学存在的问题,我们可以采取以下对策：教师主动学习,转变教学观念;充分利用合作学习教学策略;灵活采用多种教学策略,关注个体差异和需求;使用现代化教学手段;学校也应有相应的激励机制。  相似文献   

A new variant of the Pathfinder algorithm to generate large visual science maps in cubic time     

A. Quirin  O. Cordón  J. Santamaría  B. Vargas-Quesada  F. Moya-Anegón 《Information processing & management》2008

In the last few years, there is an increasing interest to generate visual representations of very large scientific domains. A methodology based on the combined use of ISI–JCR category cocitation and social networks analysis through the use of the Pathfinder algorithm has demonstrated its ability to achieve high quality, schematic visualizations for these kinds of domains. Now, the next step would be to generate these scientograms in an on-line fashion. To do so, there is a need to significantly decrease the run time of the latter pruning technique when working with category cocitation matrices of a large dimension like the ones handled in these large domains (Pathfinder has a time complexity order of O(n⁴), with n being the number of categories in the cocitation matrix, i.e., the number of nodes in the network).  相似文献   

An analysis of Differential Item Functioning on INVALSI tests,designed to explore gender gap in mathematical tasks     

《Studies in Educational Evaluation》2020

This study presents a quantitative approach based on Differential Item Functioning analysis within the Item Response Theory framework, to quantify gender differences in tackling specific mathematical items. We use this approach to explore two crucial topics in mathematics education (misconceptions in decimal numbers, and estimation) by analysing answers given by Italian students to specific mathematical items taken from a sample of 1400 items administered in INVALSI tests since 2008. For each item, we have a sample of 30,000 students per year, statistically representative of the entire Italian student population. The results section presents a didactic interpretation of the statistical evidence and shows how interdisciplinarity between statistics and mathematics education, with a mixed-method approach (Johnson & Onwuegbuzie, 2004), represents a good approach to exploring the gender gap in relation to specific constructs of math education. This approach, common in many disciplines, can also make an interesting contribution to mathematics education research.  相似文献   

Web pages as a tool for a strategic description of the Spanish largest firms     

Juan Llopis  Reyes Gonzalez  Jose Gasco 《Information processing & management》2010

The need for this study lies in the assumption that an in-depth examination of the map site of a firm that has a well-developed website can provide patterns about its corporate strategy through all the elements surrounding the organisation, and even a primary source for benchmarking. This technique has made it possible to identify the key issues in the strategic management of the most excellent large Spanish firms and also to describe trends in this sense. The methodology used consisted in a content analysis of the web pages of the Ibex35 companies of the Spanish Stock Market. Rather than focusing on the breakdown of businesses developed by each corporation, it was thought more appropriate to assess their respective corporate principles, as this would allow a better identification of the underlying managerial, organisational and strategic realities of these organisations. As a conclusion we can say that thanks to this technique, it has been possible to identify the key issues in the strategic management of the most excellent large Spanish firms. Additionally, it is shown how this way of working can be generalised to any group of enterprises.  相似文献   

基于多船队作业的东、黄海鲐鱼生物经济模型及管理策略   总被引：3，自引：0，他引：3  

张广文  陈新军  李思亮  李纲 《资源科学》2010,32(8):1627-1633

鲐鱼是我国近海大型围网和群众围网船队主要捕捞种类。如何兼顾两种渔业的利益,并从生物、经济和社会效益来科学制定渔业管理目标,是确保该资源可持续利用的重要研究内容之一。本文根据渔获统计等数据,在理论上模拟了50年内(1948年-2048年)大型围网和群众围网捕捞船队的动态变化,探讨5种方案下各渔业捕捞努力量、鲐鱼资源量、产量及利润,以及与其对应的总利润及总产量的动态变化情况。模拟结果表明:所有方案下,资源量在前10年(1998年-2008年)中都出现较大幅度的减少,随后趋于稳定并维持在较低的水平上。在基准方案下,群众围网船队在捕捞努力量、产量及利润方面占优。其余方案中,大型围网船队最终在捕捞努力量和产量占优,但其利润接近于0。结合累计产量和利润,方案c(降低大型围网成本)由于兼顾了大型围网的经济效益及群众围网的社会效益,可认为是目前适合东黄海鲐鱼长期的管理方式。  相似文献   

A catalyst for teaching critical thinking in a large university class in Taiwan: asynchronous online discussions with the facilitation of teaching assistants     

Ya-Ting C. Yang 《Educational technology research and development : ETR & D》2008,56(3):241-264

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Large eddy simulation of a particle-laden turbulent plane jet     

金晗辉  罗坤  樊建人  岑可法 《浙江大学学报(A卷英文版)》2003,4(2):175-180

Gas-solid two-phase turbulent plane jet is applied to many natural situations and in engineering systems. To predict the particle dispersion in the gas jet is of great importance in industrial applications and in the designing of engineering systems. A large eddy simulation of the two-phase plane jet was conducted to investigate the particle dispersion patterns. The particles with Stokes numbers equal to 0.0028, 0.3, 2.5, 28 (corresponding to particle diameter 1 μm, 10μm, 30μm, 100μm, respectively) inRe=11 300 gas flow were studied. The simulation results of gas phase motion agreed well with previous experimental results. And the simulation results of the solid particles motion showed that particles with different Stokes number have different spatial dispersion; and that particles with intermediate Stokes number have the largest dispersion ratio. Project (No. G19990222) supported by the Special Funds for Major State Basic Research of China  相似文献   

对巨额财产来源不明罪认定和惩处的立法思考     

黄利荣 《延安教育学院学报》2004,18(3):26-28

对巨额财产来源不明罪的研究，是当今司法界和理论界都存在较多争议的问题。本通过对巨额财产来源不明犯罪构成要件的争议、巨额财产来源不明罪的证明责任和对该罪处罚的分析，探讨了巨额财产来源不明罪在立法上的局限之处，就此为该罪名的立法完善提供参考。  相似文献