科技文献出版延迟对文献时效规律的影响     

杨静  邹梅 《情报科学》2000,18(12):1062-1063

本文将文献稳态时效规律与出版延迟规律视为对数正态分布函数,并对其进行数学分析处理,给出了两者共同作用下的文献时效规律曲线。  相似文献   

Molecular basis of familial hypercholesterolemia: An Indian experience     

Ashavaid T. F.  Altaf A. K.  Nair K. G. 《Indian journal of clinical biochemistry : IJCB》2000,15(1):11-16

Modification of platelet proteins by free radicals and glycation has been studied in the present work, as anin vitro model. The results of the two parameters, SDS-PAGE and carbonylation study are quite corroborative. We observed that the inducers like ferrous sulphate, ascorbate (mainly in supraphysiological concentration) and glucose attack the protein in a dose dependent manner, of which ferrous sulphate is most potent. Proteins from aged and degenerative conditions like malignancy and diabetes mellitus have suffered greater damage than normal adult and foetal proteins. The individual life expectancy in terms of biological versus chronological age may also be worked out from the individual stress level.  相似文献   

河南省人口现状特征分析     

吕可文  潘丛郁  徐晓霞 《安阳师范学院学报》2008,(2):97-101

人口问题始终是制约一个国家、区域全面、协调、可持续发展的重大问题。河南省作为中国第一人口大省,其在人口数量、规模、结构、素质等方面存在着突出问题,也面临前所未有的复杂形势。在综合分析河南省经济社会发展中人口现状的基础上,总结了河南省现阶段存在的人口特征及人口问题,为解决河南省人口问题和制定人口政策,促使河南省由人口大省转化为人口强省提供了基础和依据。  相似文献   

Early life stress moderates the relationship between age and prosocial behaviors     

《Child abuse & neglect》2019

BackgroundSeveral studies suggest that prosocial behaviors gradually increase with age, but others report that prosocial behaviors are fixed traits with only minor fluctuations throughout the lifespan. Early life stress may help explain these inconsistencies, as distinct types of stress have been negatively or positively associated with prosocial behaviors.ObjectiveThis current investigation used two studies to test whether distinct types of early life stress moderated the association between age and prosocial behavior.Participants and settingStudy 1 recruited undergraduate students (n = 69) between the ages of 18–35, and Study 2 was conducted on Amazon Mechanical Turk responders (n = 499) whose ages ranged from 18-74.MethodsStudy 1 employed behavioral economic tasks to measure cooperation and charitability, while Study 2 utilized an online survey to measure helping attitudes.ResultsModeration analyses revealed the association between age and cooperation was significantly weakened by a history of family violence (β=−0.37,p = 0.002), community violence (β=−0.30,p = 0.012), emotional abuse (β=−0.27,p = 0.026), and an overall summary score of early life stress (β=−0.33,p = 0.006). The relationship between age and charitability was only weakened by family violence (β=−0.24,p = 0.048). The association between age and helping attitudes was weakened by family violence (β=−0.10, p = 0.023), community violence (β=−0.13,p = 0.003), and physical neglect (β=−0.11,p = 0.018).ConclusionsCollectively, these results suggest that some types of early life stress, especially exposure to violent environments, may reduce the likelihood of prosocial behaviors increasing throughout the lifespan. This study suggests that age-related effects on prosocial behaviors may not be universal, but rather depend on individual differences in childhood stress.  相似文献   

黑色中性笔书写字迹耐久性实验分析     

史金 《档案学通讯》2020,(2):104-108

以市场上主流品牌的黑色中性笔为研究对象,参照DA/T 16—1995档案字迹材料耐久性测试法,通过干热、紫外光照、水浸、耐酸、耐碱老化实验,研究了黑色中性笔书写字迹的耐久性。结果表明,大部分品牌的黑色中性笔书写字迹耐久性优良,少数品牌的字迹耐久性较差,可擦写黑色中性笔的书写字迹耐久性差。同品牌不同型号的黑色中性笔书写字迹受老化实验的影响存在差异。  相似文献   

体育与中国人口老龄化     

杨昊霖 《搏击·武术科学》2009,(4)

文章运用文献综述研究方法对当前国内老年人体育活动的现状进行分析,研究结果表明:我国正快速进入老龄化社会,老年人从事体育活动可以有效地促进他们的健康水平。文章对此提出一些对策,以期对我国该问题的研究有所帮助。  相似文献   

废报纸不同熟化时间下脱墨技术的研究     

陈娟  万金纬 《黑龙江科技信息》2010,(35):33-34

本实验测定在不同熟化时间下的脱墨技术。脱墨采用洗涤法,浮选法,洗涤加浮选法。该三种方法均采用30min、1h、1h30min三段熟化时间,总共分为9组实验。纸品鉴定发现:白度大部分在50～70之间,整体水平都低于印刷标准,色度黄色水平基本变化不大,整体趋势是逐渐升高,以实验8效果最好。  相似文献   

身体锻炼抗衰老作用机制研究进展     

孙开宏 《四川体育科学》2007,(4):115-116

将国内最新关于身体锻炼抗衰老实验研究的主要文献报道归纳整理,分为调节免疫功能、抗自由基损伤、调节神经内分泌功能、调整脂质代谢、改善血液流变性5个方面,并作了简要评述。  相似文献   

抗坏血酸和胶原蛋白的皮肤吸收速率及其对老化肌肤的作用     

高彤彤  ;晏志勇 《宜春师专学报》2014,(6):20-21

目的：探讨和比较应用抗坏血酸及胶原蛋白对于老化肌肤的疗效和吸收速率.方法：使用抗坏血酸和胶原蛋白涂抹于健康皮肤和问题皮肤之上,观察其荧光与反射光谱的变化情况,采用皮肤光谱对皮肤组织中胶原蛋白的含量进行检验,分析和总结不同部位皮肤对不同浓度的抗坏血酸和胶原蛋白的吸收程度和修复效果.结果：皮肤可有效吸收适当浓度的抗坏血酸或胶原蛋白,适当比例的混合液可获得较好的疗效.其中0.1％的胶原蛋白溶液吸收率高于0.5％和1.0％的同类型溶液,抗皱效果较好;20％的抗坏血酸即可取得良好的淡斑效果.结论：抗坏血酸或胶原蛋白浓度适宜时皮肤吸收效果较好,混合使用浓度适当的抗坏血酸及胶原蛋白可取得较好的疗效.  相似文献   

我国人口的变化与体育课程可持续发展   总被引：5，自引：0，他引：5  

李加奎  李文辉 《四川体育科学》2002,(1):14-15

通过对我国人口的发展趋势分析，得出我囤的人口年龄结构正由成年型向典型的老年型过渡，并且就学的青少年人口数量也在减少。体育教育水平虽然由经济发展水平决定，但也和一定的人口比重、数量有密切关系。因此，人口年龄结构的变化必然会对体育教育中的课程改革有诸多方面的影响。  相似文献