Efficiency of neutron tomography in visualizing the internal structure of metal artefacts from Mapungubwe museum collection with the aim of conservation     

Farahnaz Koleini  Frikkie de Beer  M.H. Alex Schoeman  Innocent Pikirayi  Shadreck Chirikur  Gawie Nothnagel  Jacob Mabuti Radebe 《Journal of Cultural Heritage》2012,13(3):246-253

AimEstimating physical stability as well as revealing signs of fabrication in metal artefacts via two complementary nondestructive methods, neutron- and X-ray tomography were the main goals of this study.AbstractTo aid conservation management of metal artefacts improved knowledge of the internal structure and degree of corrosion therein is highly desired. In this study, neutron- and X-ray tomography were chosen as two complementary noninvasive visualization techniques to study internal structure and corrosion of five representative examples of archaeological metal artefacts from the Mapungubwe museum collection. Tomography was performed at the Neutron Radiography (SANRAD) facility of the South African Nuclear Energy Corporation where thermal neutrons as well as complementary X-rays are conveniently available under one roof. Comparative studies revealed neutron tomography to be generally superior to X-ray tomography due to the enhanced penetration properties of neutrons through the metal objects. In this paper the rich capability of neutron tomography as a nondestructive visualization aid for scientific conservation purposes is introduced and supported by results achieved for the five selected real artefacts.  相似文献   

一个美国人的中国梦          下载免费PDF全文

Jacob D. Wickham 《中国科学院院刊》2017,32(Z2):62-63

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Haptoglobin Polymorphism and Association with Complications in Ghanaian Type 2 Diabetic Patients     

Michael B. Adinortey  Ben A. Gyan  Jonathan P. Adjimani  Philomena E. Nyarko  Charity Sarpong  Francis Y. Tsikata  Alexander K. Nyarko 《Indian journal of clinical biochemistry : IJCB》2011,26(4):366-372

There is scanty information on the role of genetic factors, especially those relating to haptoglobin (Hp) phenotypes in the expression of complications among diabetes mellitus patients in Ghana. In this study, we investigated whether there is any association between Hp phenotypes and diabetic complications and to determine if association of the Hp phenotypes with diabetic complications in Ghanaian diabetics differ from those in Caucasians. A total of 398 participants were randomly recruited into the study. These comprised diabetic patients numbering 290 attending a diabetes Clinic in Ghana and 108 non-diabetic controls from the same community. Analyses of the results indicate that most of the diabetics with complications were of the Hp 2–2 (35%) and Hp 2–1 (23.9%) phenotypes. Fewer diabetics were found to be of the Hp 2–1 M phenotype. The controls were mostly of Hp 1–1 and Hp 2–1 M phenotypes. The odds ratio of having complications in a diabetic with an Hp 2–2 phenotype was 18.27 times greater than that for Hp 0–0. Hp 2–2 phenotype with its poor antioxidant activity may therefore be a useful predictor for the propensity of an individual to develop diabetes complications.  相似文献   

Promoting understanding of the interrelationships among science,technology, and society: A course for precollege teachers     

Kim Jacob  Paul Kelter  Ken Hughes 《Journal of Science Teacher Education》1991,2(2):53-56

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Putting an end to download‐and‐go: The website's role in a content marketing ecosystem          下载免费PDF全文

Jacob Wilcock 《Learned Publishing》2018,31(2):173-179

Key points

• Publishers must think of their websites as marketing tools as well as content delivery systems.
• The five major strategies of content marketing are promotion, personalization, targeting, consumerization, and analysis and optimization.
• Publishers must treat readers as customers, not simply as end users.
• Content marketing is about the environment in which content exists, as well as the form that it takes.
• To compete with pirate sites, publishers need to provide a richer user experience.
• Content marketing benefits authors and readers as well as publishers.
• Readers want the same enjoyable user experience and tailored content on all sites they visit.
• Content marketing can increase site traffic, lengthen visits, boost revenues, thwart piracy, and heighten brand impact.

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And Deliver Us to Segmentation     

Jacob L. Nelson 《Journalism Practice》2018,12(2):204-219

Non-profit news publishers, a small but growing piece of the news media environment, often explicitly attempt to build strong ties with their audiences. Many assume this approach differs from that of legacy newsrooms, which have historically kept the audience at arm’s length. In this article, I argue that this distinction has blurred. In-depth interviews with reporters and editors at a daily newspaper (The Chicago Tribune) and a local news non-profit (City Bureau) reveal that: (1) both organizations are pursuing a more collaborative relationship with their audiences; and (2) this pursuit is ill-suited for the traditional mass audience approach to news production. I conclude that journalists aspiring to work more closely with the audience find greater success when that audience is narrow to begin with.  相似文献   

Advocating for a More Effective Critical Pedagogy by Examining Structural Obstacles to Critical Educational Reform     

Jacob W. Neumann 《The Urban Review》2013,45(5):728-740

Since a major purpose of critical pedagogy is to change society by changing schools, critical pedagogy must gain an increased presence within K-12 schools. For this to happen, however, critical educators must begin to more fully recognize and appreciate the structural obstacles that schools present to critical educational change. This paper examines three of these obstacles: schools’ nature as public institutions, the fact that schools change reform efforts, and the relationship between ‘first-order’ and ‘second-order’ change and the types of changes for which criticalists often advocate. The paper ends by encouraging a smaller, more practical critical pedagogy that is focused on tangible and meaningful effect.  相似文献   

Youth in a Dark Age     

Jacob C. Solovay 《The Educational forum》2013,77(4)

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The Relationships of Perceived Health Professionals’ Communication Traits and Credibility with Perceived Patient Confidentiality     

Virginia P. Richmond  James C. McCroskey  Jacob L. Cayanus 《Communication Research Reports》2013,30(2):129-142

Patients at a large medical clinic provided data permitting an analysis of the relationships of perceived communication behaviors (nonverbal immediacy, assertiveness, and responsiveness) and source credibility (competence and caring) with perceptions of the confidentiality of their medical records. Perceptions of physicians, nurses, and support staff were employed. The results indicate that patients’ perceptions of the communication behaviors and credibility of physicians, nurses, and support staff are meaningfully related to patients’ perceptions of confidentiality. The problems of actual confidentiality and perceived confidentiality are discussed in relation to the role of communication as part of the problem and a potential part of the solution.  相似文献   

Teacher credentials and student achievement: Longitudinal analysis with student fixed effects   总被引：2，自引：0，他引：2  

Charles T. Clotfelter  Helen F. Ladd  Jacob L. Vigdor 《Economics of Education Review》2007,26(6):673

We use a rich administrative dataset from North Carolina to explore questions related to the relationship between teacher characteristics and credentials on the one hand and student achievement on the other. Though the basic questions underlying this research are not new—and, indeed, have been explored in many papers over the years within the rubric of the “education production function”—the availability of data on all teachers and students in North Carolina over a 10-year period allows us to explore them in more detail than has been possible in previous studies. We conclude that a teacher's experience, test scores and regular licensure all have positive effects on student achievement, with larger effects for math than for reading. Taken together the various teacher credentials exhibit quite large effects on math achievement, whether compared to the effects of changes in class size or to the socio-economic characteristics of students.  相似文献