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11.
Pedro Gutiérrez Bueno wrote two editions of a chemistry textbook between 1788 and 1802. The paper offers a comparative view
of both editions taking into account Gutiérrez Bueno’s biography, his intended audience and the changes related to the so-called
chemical revolution. Some conclusions are at odds with common images about scientific revolutions and the role of textbooks
in science. The analysis aims to shed some light on the multiple historical forces shaping textbooks and the way in which
scientific change is assimilated by their writers.
This research was partially supported by the program BHA2002-04611-CO3-02 相似文献
12.
Robert L. Robinson 《Higher Education in Europe》2001,26(4):567-575
In 1997, the University of Texas (UT) System initiated the development of the UT TeleCampus, a centralized facilitation point for distance learning. The TeleCampus opened its virtual doors in May 1998. At the start, its focus was entirely on support services for students. By late 1998, however, the TeleCampus had begun developing what would become collaborative benchmark on-line programmes for the UT System. Since then, in developing more than twelve complete on-line degree programmes, the administrators of the TeleCampus have learned lessons about creating and maintaining quality in collaborative, Web-based, distance, for-credit, education courses and degree programmes. Some of the key issues arising from the collaborative nature of these programmes and methods that are used to ensure that each course meets a high-quality standard are discussed. 相似文献
13.
Ramesh Chander Farhan Rizvi A. K Khanna Ram Pratap 《Indian journal of clinical biochemistry : IJCB》2003,18(2):71-79
Guggulsterone, a mixture of cis (E) and trans (Z) isomers (7∶3 w/w) was synthesized from 16-DPA. The isomers were separated
by column chromatography and evaluated for cardioprotective and antioxidant activities. Myocardial necrosis induced by isoproterenol
in rats caused marked increase in serum creatine phosphokinase and glutamate pyruvate transaminase. Simultaneously in ischemic
heart, phospholipase, xanthine oxidase and lipid peroxides were enhanced following depletion of glycogen, phospholipids and
cholesterol. Treatment with guggulsterone and its both isomers at the dose of 50 mg/kg po., significantly protected cardiac
damage as assessed by the reversal of blood and heart biochemical parameters in ischemic rats. The cardioprotective activity
of guggulsterone and of both the isomers were compared with that of gemfibrozil at the same doses. Guggulsterone and both
the isomers at tested concentrations (5–20mM) inhibited oxidative degradation of lipids in human low-density lipoprotein and
rat liver microsomes induced by metal ionsin vitro. The drug counteracted against the generation of superoxide anions (O2) and hydroxyl radicals (OH−) in non-enzymic test systems. It is suggested that cardioprotective and antioxidant activities of synthetic guggulsterone
and guggulsterone obtained from gum resinCommiphora mukul that contains isomers E & Z in the ratio of 46∶54w/w are the same. 相似文献
14.
T. Malati G. Rajani Kumari P. V. L. N. Murthy Ch. Ram Reddy B. Surya Prakash 《Indian journal of clinical biochemistry : IJCB》2006,21(1):34-40
Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the
present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma
Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating
patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and
10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase
(P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy
males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death. 相似文献
15.
Prevalence of child sexual abuse reported by a cross-sectional sample of New Zealand women 总被引:1,自引:0,他引:1
OBJECTIVE: The objective is to describe the prevalence of child sexual abuse (CSA) among women in New Zealand, document ethnic specific rates, and outline the frequency of abuse experienced and the most commonly identified perpetrators. Associations between CSA and later adverse consequences were also explored. METHODS: Retrospective report from a random sample of 2,855 women aged 18-64 years old in two regions in New Zealand. Face-to-face interviews with one randomly selected woman from each household were conducted. RESULTS: The overall prevalence rates for CSA were 23.5% for women from the urban region and 28.2% from the rural region. In both urban and rural regions, Māori women more frequently reported experiences of CSA than women from European and other ethnic groups (urban: 30.5% vs. 17.0% and rural: 35.1% vs. 20.7%). The median age of onset of the abuse was 9 years, and the median estimated age of the abuser was 30 years. Half of those who experienced CSA reported that it occurred once or twice, 27% "a few times," and 23% "multiple times." Sole perpetrators were involved in 83% of cases. The majority of cases were perpetrated by a family member, most frequently male. Compared with non-victims, victims of CSA were twice as likely to experience later intimate partner violence and violence by others. CONCLUSIONS: This study reports on a large, population-based sample in an ethnically diverse population in New Zealand, providing the first ethnic-specific rates of CSA available. Findings suggest important priorities for prevention and intervention activities. 相似文献
16.
Robinson Clinton Vũ Tú Anh Thị 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2019,65(3):443-470
International Review of Education - In the multilingual environments of Africa, national literacy policies vary in terms of the attention they give to the roles and purposes of local, national and... 相似文献
17.
Yvonne Robinson Anna Paraskevopoulou Sumi Hollingworth 《British Educational Research Journal》2019,45(6):1203-1219
Creativity has become the new watchword in UK academic and policy circles. Within this context, policy discussions about the arts and their impact emphasise economic benefits over educational value, drawing clear distinctions between quantifiable or ‘hard’ measures of impact and those described as ‘soft’, less tangible and lacking a strong evidence base. Departing from the binary logics often underpinning notions of arts impacts, this article is novel in exploring the entwined relationship between impacts seen as ‘hard’ and ‘soft’. We draw on research examining the links between arts education and young people's future trajectories and use the concept of ‘active citizenship’ to show how informal, softer skills fostered through creative learning are an important part of citizenship-making for some young people. Participants’ accounts show how improvements in soft skills can give young people opportunities for agency, which shape progression pathways leading to measurable change. This finding is directly relevant in the context of evaluations of arts impacts in the UK and abroad, and should encourage further examination of the impact of creative learning on transfer of skills as well as policy developments in this area. 相似文献
18.
19.
In healthcare practice, the sedimentation rate of red blood cells (erythrocytes) is a widely used clinical parameter for screening of several ailments such as stroke, infectious diseases, and malignancy. In a traditional pathological setting, the total time taken for evaluating this parameter varies typically from 1 to 2 h. Furthermore, the volume of human blood to be drawn for each test, following a gold standard laboratory technique (alternatively known as the Westergren method), varies from 4 to 5 ml. Circumventing the above constraints, here we propose a rapid (∼1 min) and highly energy efficient method for the simultaneous determination of hematocrit and erythrocyte sedimentation rate (ESR) on a microfluidic chip, deploying electrically driven spreading of a tiny drop of blood sample (∼8 μl). Our unique approach estimates these parameters by correlating the same with the time taken by the droplet to spread over a given radius, reproducing the results from more elaborate laboratory settings to a satisfactory extent. Our novel methodology is equally applicable for determining higher ranges of ESR such as high concentration of bilirubin and samples corresponding to patients with anemia and patients with some severe inflammation. Furthermore, the minimal fabrication steps involved in the process, along with the rapidity and inexpensiveness of the test, render the suitability of the strategy in extreme point-of-care settings. 相似文献
20.