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141.
Comparison of oil and egg tempera paint systems using time-of-flight secondary ion mass spectrometry
Zachary E. Voras Kristin deGhetaldi Brian Baade Eric Gordon Glenn Gates Thomas P. Beebe 《文物保护研究》2016,61(4):222-235
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is quickly becoming a critical tool in the field of art conservation. This technique provides high-resolution spatial maps of both inorganic and organic components located within cross-sectional samples collected from works of art. With recent advances in surface analysis, ToF-SIMS can now be used to identify specific amino acids present in protein-containing materials as well as fatty acids in drying oils. For example, the detection of the ion fragment associated with the amino acid hydroxyproline can be used to confirm the use of animal glue in a paint sample. As an analytical technique, ToF-SIMS avoids the need for derivatization/silylation reagents, with no interference by the presence of pigments. Furthermore, the layered systems that are often encountered in historical paint samples remain intact throughout the analytical procedure. This allows for the co-localization of organic and inorganic species in specific layers (e.g. egg yolk paint atop a glue ground). Because of this ability to localize the analytical signal to approximately 6?µm or less, the mass spectral information can be used to produce mass-resolved and spatially-resolve images which can be correlated to previous studies of the same samples. In this study, ToF-SIMS was used to analyze a paint cross section obtained from a painting attributed to Raphael, and another from a painting by the Sienese artist Matteo di Giovanni. 相似文献
142.
Mary Grace Antony Ryan J. Thomas 《Journal of International and Intercultural Communication》2017,10(1):4-24
The recent migration of 65,000 children across the southwestern border, coupled with allegations of abuse by the U.S. Border Patrol, enables the investigation of an overlooked immigrant category: the unaccompanied youth migrant. Analyzing audience responses to news reports of the abuse, we find that established disparaging immigrant tropes apply, describing the children as an economic burden, disease carriers, and offspring of irresponsible families. We uncover two new themes: Youth migrants are channels whereby criminals may infiltrate the U.S., and manipulate legal authorities to remain in the U.S. Finally, we demonstrate how global compassion is strategically deployed to qualify harsh retaliatory measures. 相似文献
143.
Iasonas Lamprianou Thomas Christie 《Educational Assessment, Evaluation and Accountability》2009,21(4):329-345
Accepting that school based assessment may have the potential to bring additional reliability to the assessment outcomes of an educational system, this research uses Generalizability Theory to address the question “why school based assessment is not a universal feature of high stakes assessment systems”? Three major issues are identified: (a) there is a conflict between the psychometric model and classroom assessment practice; (b) different schools are not equally effective; and, (c) teachers’ judgments are frequently accused of being biased. The role of public examination boards is discussed in this context. 相似文献
144.
Despite science learning in settings such as science museums being recognized as important and given increasing attention in science education circles, the investigation of parents’ and their children’s metacognition in such settings is still in its infancy. This is despite an individual’s metacognition being acknowledged as an important influence on their learning within and across contexts. This research investigated parents’ metacognitive procedural and conditional knowledge, a key element of their metacognition, related to (a) what they knew about how they and their children thought and learned, and (b) whether this metacognitive knowledge influenced their interactions with their children during their interaction with a moderately complex simulation in a science museum. Parents reported metacognitive procedural and conditional knowledge regarding their own and their children’s thinking and learning processes. Further, parents were aware that this metacognitive knowledge influenced their interactions with their children, seeing this as appropriate pedagogical action for them within the context of the particular exhibit and its task requirements at the science museum, and for the child involved. These findings have implications for exhibit and activity development within science museum settings. 相似文献
145.
146.
Martin?VeselyEmail author Thomas?Baron Jean-Yves?Le?Meur Tibor?Simko 《Publishing Research Quarterly》2004,20(1):77-83
Conclusion In this paper we briefly described the current status of research in the field of digital libraries interoperability, mainly
with respect to federated data processing such as permitted within the Open Archive Initiative framework. We then presented
the CERN Document Server Software suite that is a free software package main-tained by CERN providing an online digital library
solution for mid- to large-sized document repositories. The set of CDSware modules was described and the differ-ences with
other existing tools briefly mentioned. Finally we have mentioned a typical usage statistics illustrating the scope of grey
literature and networked con-ditions of the CERN Document Server.
We pointed out that the current trend in grey literature management goes toward institutional repositories build upon the
distributed and federated model. Further research is going on within the CDS collaboration in this area, focused particularly
on (i) semantic interoperability using ontologies in distributed and federated data processing and (ii) ranking technologies
when searching grey literature in OAI compliant repositories. 相似文献
147.
Pam Sammons Sally Thomas Peter Mortimore Adrian Walker Rosemary Cairns John Bausor 《School Effectiveness & School Improvement》2013,24(3):286-309
As part of a large‐scale study of the ability of 94 secondary schools to promote academic achievement, case studies of six outlier schools were conducted and headteachers (principals) and their deputies were questioned about the processes of effectiveness. The analysis of their responses ‐ grouped by the performance of their school (measured by value added analyses of three years of public examination results) as effective, ineffective or mixed ‐ reveals considerable support for previously cited characteristics of effective schooling. Despite the limitations imposed by a reliance on the use of retrospective accounts, the study takes forward the field of school effectiveness in its search for generalisable findings and coherent theory. 相似文献
148.
Susie Thomas 《Changing English: An International Journal of English Teaching》2006,13(2):185-196
This article explores the ambiguities, ironies and ethical dilemmas of using real people in fiction and the relation between memoir and fiction. After looking at how this debate has surfaced as a theme in Hanif Kureishi's fictional works, the author examines his memoir, My ear at his heart: reading my father, and concludes that Kureishi's memoir provides an important perspective on his earlier work and constitutes a valuable addition to the literature of family life, identity and migration. 相似文献
149.
Dale D. Long Dr. Thomas G. Teates Paul F. Zweifel 《Journal of Science Teacher Education》1992,3(4):109-113
Conclusion It seems reasonable to conclude that the impact of these projects has been extensive and that we have met our basic objectives
regarding the improvement of science education for the target teachers and students. The long-term goal of improved scientific
literacy of at least a part of the citizens of this country and world can only be assessed by some form of longitudinal study
that is beyond the scope and funding for these projects. But our assessment of what has been accomplished in the short term
efforts seems to indicate very positive gains in those areas of knowledge, confidence, and pedagogical capability that we
believe will enable the participants to make contributions to the improvement of scientific literacy for the students with
whom they work.
In short, we believe we have had two successful and worthwhile programs that have been useful and effective. 相似文献
150.
Video-assisted thoracoscopic surgery (VATS) for bilateral primary spontaneous pneumothorax 总被引:3,自引:0,他引:3
Chen YJ Luh SP Hsu KY Chen CR Tsao TC Chen JY 《Journal of Zhejiang University. Science. B》2008,9(4):335-340
Objective:To review our experience of the treatment of bilateral primary spontaneous pneumothorax (PSP) by video-assisted thoracoscopic surgery (VATS). Materials and methods: Retrospective chart review was followed by an on-clinic or telephone interview. Patients were cared for by one thoracic surgeon in four medical centers or community hospitals in Northern and Central Taiwan. Thirteen patients with bilateral PSP underwent bilateral VATS simultaneously or sequentially from July 1994 to December 2005. Results: Twelve males and one female, with age ranging from 15 to 36 years (mean 23.1 years), were treated with VATS for bilateral PSP, under the indications of bilateral pneumothoracis simultaneously (n=4) or sequentially (n=9). The interval between the first and second contra-lateral VATS procedure for non-simultaneous PSP patients ranged from 7 d to 6 years. Eleven of 13 patients (84.6%) had prominent pulmonary bullae/blebs, and underwent bullae resection with mechanical or chemical pleurodesis. The mean operative time was (45.6±18.3) min (range 25-96 min) and (120.6±28.7) min (range 84-166 min) respectively for the non-simultaneous (second VATS for the recurrence of contralateral side after first VATS) and simultaneous (bilateral VATS in one operation) procedures. There was no postoperative mortality. However, prolonged air leakage (>7 d) occurred in one patient (7.7%) who recovered after conservative treatment. The mean duration of chest tube drainage was 3.1 d and the median follow up period was 3.4 years. Conclusions: VATS is a safe and effective procedure in the treatment of bilateral PSP. Bilateral VATS is only recommended for patients with simultaneously bilateral PSP, because the incidence of recurrence, even with visible bullae, was not so high in my group and in some previous literature. Bilateral VATS in a supine position should only be used in selective cases, because of possible pleural adhesion or hidden bullae on the posterior side. 相似文献