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1.
U. Casellato F. Fenzi P. Guerriero S. Sitran P. A. Vigato U. Russo M. Galgani M. Mendera A. Manasse 《Journal of Cultural Heritage》2003,4(4):337-353
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties. 相似文献
2.
Understanding the Information Needs of Academic Scholars in Agricultural and Biological Sciences 总被引:4,自引:0,他引:4
This study investigates the information needs of faculty and graduate students in agricultural and biological sciences. Qualitative research methods, interviews and focus groups, were used to examine what types of information these scholars need for their research, teaching and learning, how they seek that information, and perceptions. The implications for library service are discussed. 相似文献
3.
Objective: To determine the effective nucleotide sites of ribozymes against HCV, and obtain a highly effective, nontoxic and
inexpensive antisense ribozyme specific for HCV. Methods: Two effective ribozymes, targeted to HCV 5’NC region and C region,
were designed and synthesized. Eukaryotic expression vectors, pSV2-gpt. CD-SR (, containing either HCRZNC or HCRZC were constructued
and transfected into MT-2 cells, which had been infected by HCV. Quantitative PCR and hydridization were used to determine
the effect of inhibition of HCV by ribozymes. Results: HCRZNC and HCRZC suppressed the replication of HCV by 54.7% and 62.1%,
respectively. Furthermore, when both ribozymes were cotransfected into cells, they suppressed replication by 78.8%. Conclusion:
Two specific antisense ribozymes have strong inhibitory effects on the replication of HCV in cultured cells, and have better
effect when used together. 相似文献
4.
5.
Conclusion Garrison’s (2000) review of distance education theories describes the current need for ”sustained real two-way communication
... that refiect(s) a collaborative approach to distance education” (p. 13). One way to apply such theories to research and
coursework is to use collaborative documents to promote transactions culminating in deliberation among the key players. Such
deliberation can create ”a particular kind of democratic public culture among the deliberators: listening as well as talking,
sharing resources, forging decisions together rather than only advocating positions taken earlier, and coming to disagreement”
(Parker, Ninomiya, & Cogan, 1999, p. 129).
Her research interests are collaborative learning in distance education, impact of culture on online learners, and design
of online instruction for constructivist learning environments.
Her primary research interests are in design considerations for collaborative online environments and in the powers of shared
multimedia for enhancing personal growth, multicultural understanding, and global awareness. She investigates visual messages:
how they can be shared and interpreted by learners, their impact, and how their impact can be researched.
Her research interests are in computer and network-based foreign language and cultural learning. 相似文献
6.
7.
A Framework for Research on Large-scale Reform 总被引:1,自引:0,他引:1
Variation in the success of large-scale reform is afunction of many factors interacting at many ``levels'.Built on a selective review of the evidence aboutlarge-scale reform, this paper provides a framework forexplaining such variation, as well as assessing progressin that direction. Relevant factors influencing reformsuccess, according to the framework, include broad international social, economic and political trends bearing on education, characteristics of national educationalpolicies and strategies for their implementation, and localconditions conceptualized in terms of a model of workplaceproductivity; this model is defined by local practitioners' motivation, capacity, and the organizationalconditions in which they work. This framework has been usedto guide the external evaluation of the National Literacy andNumeracy Strategies. 相似文献
8.
This study compared the performance of children with reading disability (RD) and normal reading achievement (NRA) on tasks
of serial rapid naming, verbal fluency, letter-based word retrieval, and articulatory speed. The groups, composed of children
at two discrete age levels, one younger and one older, were matched for age, gender, and neighborhood school. Analyses of
the on-line measurement of the children’s serial rapid naming indicated that the children with RD had significantly larger
reaction times and production durations than their NRA peers despite similar levels of accuracy. They also performed significantly
worse on the categorical verbal fluency task, the letter-based word retrieval task, and the test of articulatory speed. The
findings suggest that both access and post-access processes, such as oral-motor inefficiency that extends the duration of
word production, may be implicated in the slower serial rapid naming that has typified many samples of children with RD.
This work was supported in part by Basil O’Connor Research Grant 5-340 from the March of Dimes Birth Defects Foundation, a
Scholarly and Creative Activity Award and sabbatical leave from California State University, Long Beach and grant #DCO 1904-01
from the National Institute on Deafness and Other Communication Disorders of the NIH to the first author. 相似文献
9.
This study investigated the effect of type of control and level of feedback during computer-based instruction. Subjects completed a computer lesson about the microscope that presented either mandatory or optional practice questions. Practice was accompanied by either elaboration feedback, correct-answer feedback, or no feedback. Results indicated that level of feedback had a significant effect on achievement and attitudes. Implications for including feedback in computer-based instruction are discussed. 相似文献
10.
本首先分析了当前我国专科教育所面临的发展困境与成因,进而提出了改革我国专科教育体制、建立新型专科教育运行机制的构想与相关的政策性建议。作认为,作为高等教育的一个重要组成部分,专科教育为我国的社会主义教育事业作了重要贡献,但目前又进入到一个新的发展转型期,挑战与发展的机遇关存;改革计划管理的约束的体制,寻求办学效益和社会效益的统一,建立起与社会主义市场经济体制相适应的专科教育体制与机制,实现教育体制与学校功能的战略性调整,是现阶段专科教育改革发展的必然趋势和重要条件。 相似文献