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901.
Vanessa Otero Joana V. Pinto Leslie Carlyle Márcia Vilarigues Marine Cotte 《文物保护研究》2017,62(3):123-149
The Winsor & NewtonTM (W&N) nineteenth century archive database includes digitised images of hand-written instructions and workshop notes for the manufacture of their artists’ materials. For the first time, all 183 production records for yellow lead chromate pigments were studied and evaluated. They revealed that W&N produced essentially three pigment types: lemon/pale based on mixed crystals of lead chromate and lead sulphate [Pb(Cr,S)O4]; middle on pure monoclinic lead chromate [PbCrO4]; and deep that contains the latter admixed with basic lead chromate [Pb2CrO5]; accounting for 53, 22, and 21% of the production, respectively. Production records for primrose (4%) were also included since the formulation results in mixed crystals with a high percentage of lead sulphate, which, according to the literature, leaves it more prone to degradation. Each pigment type is characterised by only one or two main synthetic pathways; process variations reveal a systematic and thorough search for a high-quality durable product. A comparison of the chemical composition of pigment reconstructions with early W&N oil paint tubes showed that their records entitled ‘pale’ and ‘lemon’ correlated with the pigment in their tube labelled chrome yellow and, ‘middle’ and ‘deep’ with the label chrome deep. Lemon and middle pigment formulations were made into oil paints to assess their relative photo-stability. The degradation process was followed by colorimetry and was studied by synchrotron radiation-based techniques. Based on the X-ray absorption spectroscopy data, the possibility for creating a stability index for chrome yellows is discussed. 相似文献
902.
Jo Ann F. Murphy 《图书馆管理杂志》2017,57(7):742-757
In 2015, student learning programs at the University of Saskatchewan moved organizationally to the university library. While these services resided physically in the library as part of the Learning Commons partnership, this recent change presents the library with a new focus and responsibility for broader student learning support and academic skill development. Highlighting examples of organizational integration of student learning support, this article uses a proximity perspective, suggesting that geographical proximity of services in the learning commons does not go far enough to achieve the deeper collaboration and integration necessary for holistic and integrated learning, and that organizational proximity is needed. 相似文献
903.
To assess the relevance of the Public Library System in the political agenda, programs presented by the Political Parties competing in Regional and Local elections in the Spanish Region of Castilla-La Mancha were analyzed and the proposals about these library institutions were identified.
All Regional programs were collected and also an ample sample from the Municipalities for the 2007 and 2015 elections, trying to find the differences influenced by the impact of the financial crisis and recession on the public-library policies.
The conclusion arrived at was that, although the Public Libraries may be reasonably present in the studied programs, there is a low awareness by the Political Parties of the main problems. 相似文献
904.
Metrics on open access (OA) availability of content published in scholarly journals (i.e. content licences, copyright ownership, and publisher‐stipulated self‐archiving permissions) are still scarce. This study implements the four core variables of the recently published Open Access Spectrum (OAS) (reader rights, reuse rights, copyright, and author posting rights) to measure the level of openness in all 1,728 Spanish scholarly journals listed in the Spanish national DULCINEA database at the end of 2015. Data exported from the database and used as variables for the analysis were: journal research area, type of publisher, type of access, self‐archiving and reuse policy, and type of Creative Commons (CC) licence used. Out of the total number of journals (1,728), 1,285 (74.5%) published their articles OA immediately after initial publication and thus received the maximum OAS score for reader rights; 37.5% of all journals used CC licences, and 79.5% allowed self‐archiving in some form. In 72% of journals, authors retained or publishers granted broad rights, which included author reuse and authorization rights (for others to reuse), whilst 13.5% did not specify any terms for copyright transfer. Similar studies could be carried out on other countries as this would enable comparisons of the general adoption and form of openness in different parts of the world. 相似文献
905.
Besiki Stvilia Charles C. Hinnant Shuheng Wu Adam Worrall Dong Joon Lee Kathleen Burnett Gary Burnett Michelle M. Kazmer Paul F. Marty 《Library & information science research》2017,39(2):85-97
This study examined factors that might affect researchers' willingness to collaborate with a specific researcher and the priorities given to those factors. In addition, it investigated how researchers determined the ownership of collaborative project data and how they determined the order of authorship on collaborative publications in condensed matter physics. In general, researchers rated their intrinsic motivations the highest, such as the quality of ideas a potential collaborator might have and their satisfaction with a past collaboration, followed by their extrinsic motivations, such as the complementary knowledge, skills, or resources the collaborator could provide. In addition, researchers who had a greater number of collaborative projects and researchers who had served as a project PI or co-PI valued the deep-level, personality-related characteristics of a collaborator higher than did those who had not. Younger researchers were more risk averse and more concerned with a collaborator's reputation and the possible cost of a collaboration decision. Additionally, younger researchers indicated more often than older researchers that they did not know whether their project teams followed any rules or norms or engaged in negotiation to determine the order of authorship on collaborative publications. 相似文献
906.
Ilene F. Rockman 《Innovative Higher Education》1987,12(1):10-15
The opportunity for library users to design and execute their own database searches through direct access to computerized data sources is known as end-user searching. Due to the proliferation of microcomputers and changes in software design, the phenomenon is gaining widespread support among libraries across the country. This paper describes three methods of education and training-course-integrated, classroombased and self-service. The role of the librarian is identified in each.She also serves as the Coordinator of End-User Instruction for the library. 相似文献
907.
Prelinguistic babbling often seems remarkably speech-like, not because it has recognizable words but because it seems to have adult-like prosody. To quantify this impression, we compared disyllabic sequences from five infants and five adults in terms of the use of frequency, intensity, and duration to mark stress. Significantly larger values for the three acoustic variables were observed on stressed than on unstressed syllables independent of syllable position for both groups. Adults showed the correlates of utterance final syllables--lower f0, lower intensity, and longer duration; infants showed only decrease in intensity. Ratios for stressed to unstressed syllables and participation of the three variables in stress production in individual disyllables were highly similar in both groups. No bias toward the English lexical trochaic stress pattern was observed. We conclude that infants in English environments produce adult-like stress patterns before they produce lexical items, which specify stress. Acoustic and perceptual analyses are used to explore stress marking by prelinguistic infants in an English language environment. Results show that infants employ the three acoustic correlates of stress in individual syllables in a manner largely similar to that of adult speakers, although they do not show second-syllable declination effects or an English language trochaic stress bias. 相似文献
908.
Glenda A. Gunter Robert F. Kenny Erik H. Vick 《Educational technology research and development : ETR & D》2008,56(5-6):511-537
We are witnessing a mad rush to pour educational content into games in an ad hoc manner in hopes that player/learners are motivated simply because the content is housed inside a game. A failure to base educational game design on well-established learning and instructional theories increases the risk of the game failing to meet its intended educational goals, and yielding students who are entertained but who have not acquired any academic skills or knowledge. Our review of standalone educational games has shown that they are not always based on sound educational principles and theories. We contend that, if academic learning is to take place, a new design paradigm must be developed. This article discusses the RETAIN design and evaluation model for educational games that was developed to aide in the evaluation of how well academic content is endogenously immersed and embedded within the game’s fantasy and story context, promoters transfer of knowledge, and encourages repetitive usage to that content becomes available for use in an automatic way. 相似文献
909.
Margaret Tresch Owen Julia F. Klausli Ana-Maria Mata-Otero Margaret O'Brien Caughy 《Early education and development》2008,19(2):302-329
Research Findings: Child care delivery practices promoting continuous, primary caregiver-child relationships (relationship-focused child care) were evaluated for 223 preschool-age children (45% African American, 55% Latino) attending child care centers serving low-income children. Both relationship-focused and non-relationship-focused centers were accredited by the National Association for the Education of Young Children. Children in relationship-focused programs received more sensitive, involved, and affectionate caregiving and were more engaged with their caregivers than children in comparison centers, but some differences were greater for African American children. Outcomes associated with relationship-focused care included greater parent-reported child compliance and closer parent-caregiver relations, but no consistent benefits for cognitive school readiness, receptive language, or child behavior problems were found. Follow-up assessments were completed 1 year later for 119 children who remained in their programs. Social and cognitive outcomes improved over time, but some changes were moderated by child race/ethnicity and center type. Over time, parents reported greater child compliance and caregivers reported better parent-caregiver relationships in relationship-focused programs. Practice or Policy: Some social benefits of continuous, primary caregivers were found, but children's cognitive competencies improved with sustained attendance at these accredited programs regardless of the relationship-focused practices. 相似文献
910.
Libby F. Gerard Jane B. Bowyer Marcia C. Linn 《Journal of Science Education and Technology》2008,17(1):1-18
Reforms such as technology-enhanced instruction require principal leadership. Yet, many principals report that they need help
to guide implementation of science and technology reforms. We identify strategies for helping principals provide this leadership.
A two-phase design is employed. In the first phase we elicit principals’ varied ideas about the Technology-enhanced Learning
in Science (TELS) curriculum materials being implemented by teachers in their schools, and in the second phase we engage principals
in a leadership workshop designed based on the ideas they generated. Analysis uses an emergent coding scheme to categorize
principals’ ideas, and a knowledge integration framework to capture the development of these ideas. The analysis suggests
that principals frame their thinking about the implementation of TELS in terms of: principal leadership, curriculum, educational
policy, teacher learning, student outcomes and financial resources. They seek to improve their own knowledge to support this
reform. The principals organize their ideas around individual school goals and current political issues. Principals prefer
professional development activities that engage them in reviewing curricula and student work with other principals. Based
on the analysis, this study offers guidelines for creating learning opportunities that enhance principals’ leadership abilities
in technology and science reform. 相似文献