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11.
A guide for the perplexed: Scientific educational research, methodolatry, and the gold versus platinum standards 总被引:1,自引:0,他引:1
The paper opens by characterizing recent discourse about empirical educational research as the “new Babel”-critics, using different theoretical vocabularies and making different deep assumptions about the nature of social life, are failing to communicate with each other. After locating some of the critical positions on a left-right continuum, the main discussion focusses upon the end of this continuum where there are located the recent attempts to restore rigor to educational research by using the so-called “gold standard” of randomized field trials. It is argued that positions at this end of the continuum misrepresent the nature of science, and some examples are briefly mentioned in order to covey the point that it is fruitful to view scientists as making convincing cases, cases that appeal to a wide variety of evidence. This assessment of scientific cases is called the “platinum standard”. 相似文献
12.
Using data from Web of Science, this research investigates how physical science researchers funded by the Canadian Institutes of Health Research complied with its open access policy, and compares the citation counts of articles published through gold and green models.It was found that, for articles published between 2008 and 2015, 9% were available through gold open access routes and 13% were available through green routes; most were not openly accessible. Citation rates were comparable for green open access and non-open access articles, but citation rates for gold open access articles were lower. After controlling for publication year, citation rates of gold, green, and non-open access articles were comparable. Among gold open access articles, citation rates were highest for open access journals with article processing charges, but after controlling for publication year, articles published in hybrid journals, followed by those in open access journals with article processing charges, achieved the highest citation rates. Articles published in free open access journals had the lowest citation rates. The results suggest that green open access is the most economical approach to comply with open access policies, and that it provides researchers with at least as much research impact as gold open access. 相似文献
13.
高飞燕 《商丘职业技术学院学报》2008,7(1):54-55
小说《金瓶梅》心理描写的特点是,通过人物的言语和行动,尤其是运用细节,从细微处来省察人物内心的微妙变化,将心理活动呈现在读者面前。在《金瓶梅》之前的中国古代小说,这一手法采用的并不多见,而《金瓶梅》在这一方面却是做得非常成功。这种表现手法似乎已成为作者自觉的行为,这是古代小说观的一个进步。 相似文献
14.
Krishnan Gokuladhas Subramaniyan Jayakumar Balan Rajan Ramasamy Elamaran Chengalvarayan Subramani Pramila Mani Gopikrishnan Sasivarman Tamilarasi Thiruvengadam Devaki 《Indian journal of clinical biochemistry : IJCB》2016,31(2):171-184
Liver cancer is the fifth most common cancer and is still one of the leading causes of death world wide, due to food additives, alcohol, fungal toxins, air, toxic industrial chemicals, and water pollutants. Chemopreventive drugs play a potential role in liver cancer treatment. Obviously in the production of anticancer drugs, the factors like poor solubility, bioavailability, biocompatibility, limited chemical stability, large amount of dose etc., plays a major role. Against this backdrop, the idea of designing the chemopreventive nature of bio flavanoid hesperetin (HP) drug conjugated with pegylated gold nanoparticles to increasing the solubility, improve bioavailability and enhance the targeting capabilities of the drug during diethylnitrosamine (DEN) induced liver cancer in male wistar albino rats. The dose fixation studies and the toxicity of pure HP and HP conjugated gold nanoparticles (Au-mPEG(5000)-S-HP) were analysed. After concluded the dose fixation and toxicity studies the experimental design were segregated in six groups for the anticancer analysis of DEN induced HCC for 16 weeks. After the experimental period the body weight, relative liver weight, number of nodules and size of nodules, the levels of tumor markers like CEA, AFP and the level of lipid peroxidation, lipid hydroperoxides and the activities of antioxidant enzymes were assessed. The administration of DEN to rats resulted in increased relative liver weight and serum marker enzymes aspartate transaminase, alanine transaminase, alkaline phosphatase, lactate dehydrogenase, and gamma glutamyl transpeptidase. The levels of lipid peroxides elevated (in both serum and tissue) with subsequent decrease in the final body weight and tissue antioxidants like superoxide dismutase, catalase, reduced glutathione, glutathione peroxidise, and glutathione reductase. HP supplementation (20 mg/kg b.wt) significantly attenuated these alterations, thereby showing potent anticancer effect in liver cancer and the HP loaded gold nanoparticels (Au-mPEG(5000)-S-HP) treated animals shows the better treatment than the pure HP due to the solubility of drug, bioavailability and the target drug delivery of the biodegradable polymer. Histological observations were also carried out, which added supports to the chemopreventive action of the pure HP and HP loaded gold nanoparticles (Au-mPEG(5000)-S-HP) against DEN induction during liver cancer progression. These findings suggest that HP loaded gold nanoparticels (Au-mPEG(5000)-S-HP) shows better efficacy than the pure HP against lipid peroxidation, hepatic cell damage and protects the antioxidant system in DEN induced hepatocellular carcinogenesis. 相似文献
15.
Kingsley Burlinson 《中国科技期刊研究》2007,23(1):65-71
The acoustic decrepitation method heats a small monomineralic sample and counts pressure impulses as the inclusions burst when they develop high internal pressures. For aqueous fluids, the decrepitation temperature is correlated with the homogenisation temperature, but gas rich fluids give a distinct and characteristic low temperature decrepitation peak which can be used to recognize gas rich fluid inclusions. This information is useful in exploration for Au deposits, which are frequently associated with CO2 rich and sometimes CH4 rich fluids. This distinctive decrepitation occurs because the CO2 rich inclusion fluids expand according to the gas law and develop internal pressures high enough to burst the host mineral grain at temperatures well below their homogenisation temperatures. In contrast, aqueous fluids condense to a liquid and vapour phase during post-entrapment cooling. Upon subsequent heating their internal pressures do not increase significantly until after homogenisation to a single phase occurs and hence they do not decrepitate "prematurely" as gas rich inclusions do. This behaviour is usually regarded as an annoyance in conventional microthermometric homogenisation studies, but can readily be used as an exploration aid to find mineralisation deposited from such gas rich fluids. Decrepitation results on samples from Cowra Ck, NSW, Australia, which have also been microthermometrically measured for CO2 content, show that amounts of less than 5 mole % CO2 are easily distinguished by decrepitation and amounts as low as 1 mole % CO2 may be determinable. Examples of the use of acoustic decrepitation in the study of 6 gold mines in the Shandong and Hebei provinces of China are discussed. 相似文献
17.
招-平断裂是胶东招掖金矿带的主要控矿断裂,其上盘金矿床受NE向断裂构造控制,赋矿围岩为胶东群变质岩,金矿化以含金硫化物石英脉为主。通过首次对招远灵雀山金矿床富金石英脉石英流体包襄体Rb-Sr等时线年龄的测定,获得116±23Ma成矿年龄。从而说明招-平断裂带上盘金矿大规模成矿期发生于早白垩世的构造体系转折期。对富金石英脉石英流体包襄体同位素特征研究表明。该地区成矿热液均以幔源为主,具有与招掖金矿带其它金矿类似的成矿热液系统。由此可以看出招.平断裂带上盘也具有良好的成矿条件。 相似文献
18.
无氰镀金用亚硫酸金钠含金量的测定 总被引:1,自引:0,他引:1
利用重量法和碘量法分别测定了无氰镀金用亚硫酸金钠的含金量。分析比较测定结果,得出较佳测定方法,即二盐酸十亚硫酸钠还原金重量法。该法操作简单,准确度高,标准偏差不大于0.05%。 相似文献
19.
公秀梅 《蒙自师范高等专科学校学报》2006,4(6):28-30
从行动元看,《金锁记》表层上最重要的行动元是金钱欲和爱情欲,它表现的是欲望的悲剧,然而在更深层次上,这种欲望受制于最高级的施动者———男权社会的意识形态;从时间处理看,《金锁记》是回顾叙述,采用场景、省略、概要、停顿等时间变形方式,体现了张爱玲“参差的对照”的美学原则。 相似文献
20.
古籍"金镶玉"装订修补法是特殊的加衬纸修复法,始于明代,在清代被广泛应用于文献修复。金镶玉有多种做法,其外观呈蝴蝶装、线装等形式。因其对文献的外观改变较大,只有当古籍书叶边缘局部糟朽发脆而危及内文信息、古籍的天头、地脚或批注文字以外的空白处过于狭小等,才可以适当考虑采用金镶玉修补装订法来修复。 相似文献