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971.
ABSTRACT The restoration of the Roman building of the third-fourth century CE called Minerva Medica, in Rome, highlighted a problem concerning the choice of the color of the bricks for integration. Current conservation practice in Italy favours a restoration that as much as possible is consistent with the original but leaves some visible differences to a careful observer. Color measurement is usually performed using portable spectrocolorimeters that provide the reflectance spectrum and also colorimetric parameters such as L* a* b*, h* L* C*, RGB, etc. In other sectors, such as for olive oils, for wines, and also for the colors of commercial products, sensory panels are used to provide results of difference/similarity and are known to be similar to observations made by consumers. In this study, data from a top quality spectrocolorimeter and from a sensory panel are compared. Twenty non-professional people were involved in the comparison between seven restoration bricks and three ancient Roman bricks from the studied site. Observations took place in a room with controlled lighting, and each observer filled out a sensory card using about 2000 known comparison colors. Comparison of the results was carried out with graphic methods and by means of cluster analysis. The results show that the sensory panel could be a useful alternative to colorimetry, while cluster analysis allowed a significant response to questions posed by conservation professionals, and was confirmed by other graphic-statistical methods. 相似文献
972.
Ghinea R Ugarte-Alvan L Yebra A Pecho OE Paravina RD Perez Mdel M 《Journal of Zhejiang University. Science. B》2011,12(7):552-562
This study deals with the influence of surface roughness on the color of resin composites. Ten resin composites (microfilled,
hybrid, and microhybrid) were each polished with 500-grit, 1 200-grit, 2 000-grit, and 4 000-grit SiC papers. The roughness
parameter (R
a) was measured using a Plμ confocal microscope, and field-emission scanning electron microscope (Fe-SEM) images were used
to investigate filler morphology. Color was measured using a spectroradiometer and a D65 standard illuminant (geometry diffuse/0°
specular component excluded (SCE) mode). Surface roughness decreased with grit number and was not influenced by filler size
or size distribution. A significant influence of R
a on lightness (L*) was found. Lightness increased with decreases in roughness, except for specimens that underwent polishing procedure 4 (PP4;
500-grit, 1 200-grit, 2 000-grit, and 4 000-grit SiC papers consecutively). Generally, it was found that surface roughness
influenced the color of resin composites. The composites that underwent PP1 (500-grit SiC paper) exhibited significant differences
in chroma (C*), hue (h°), and lightness (L*) compared to composites that underwent PP3 (500-grit, 1 200-grit, and 2 000-grit SiC papers consecutively) and PP4. Color
difference (ΔE*) between the polishing procedures was within acceptability thresholds in dentistry. 相似文献
973.
Gavin Boyce Angela Greenwood Amy Haworth Jacky Hodgson Chris Jones Gary Marsh Maria Mawson Rosa Sadler 《The Journal of Academic Librarianship》2019,45(5):102046
Over the course of 2018 the University of Sheffield Library conducted a series of interviews and workshops with stakeholders as part of a strategic project to reflect on the value of the university library in the 21st century. Using a mixed methodology, participants were asked to reflect upon the future Higher Education (HE) environment for the university and, for academic participants, their discipline. In this context participants were also asked to reflect upon the future value of the University Library in a series of questions designed to elicit value statements using a tool which the project group have called the ‘Wheel of Value’. The resulting reflections upon the future environment have been grouped into four categories reflecting the drivers for change; Digitalisation, Student Experience, Diversification and Collaboration recognizing that there is considerable overlap and interconnection between these. The reflections on the future value of the library are presented by Wheel of Value higher order categorization. This approach proved useful in eliciting responses from participants in the face of recognized difficulty in getting beyond current views of the library and the approach is recommended to other universities looking to carry out a similar project. The results of this research will be used to inform the development of a view of the library for the purpose of engaging with our university community and key partners. 相似文献
974.
975.
Latinos are the largest minority group in the United States (U.S. Census, 2014), yet this term comprises individuals from multiple ethnicities who speak distinct varieties of Spanish. We investigated whether Spanish–English bilingual children (N = 140, ages 4–17) use Spanish varieties in their social judgments. The findings revealed that children distinguished varieties of Spanish but did not use Spanish dialects to make third-person friendship judgments until 10–12 years; this effect became stronger in adolescence. In contrast, young children (4–6 years) made friendship judgments based on a speaker's language (English, Spanish). Thus, using language varieties as a social category and as a basis for making social inferences is a complex result of multiple influences for Spanish-speaking children growing up bilingual in the United States. 相似文献
976.
Anne D. Lackritz Maria Cseh Donald Wise 《Mentoring & Tutoring: Partnership in Learning》2019,27(1):5-25
The purpose of our multi-case study was to understand the experiences of non-novice New York City and Washington, DC public charter school principals who had participated in leadership coaching as a component of their leadership development. Eight New York City and Washington DC public charter school principal cases were selected through purposeful sampling. Data were collected through semi-structured interviews, documents, and artifacts, which were analyzed, coded and grouped into three broader themes: the coaching process, the impact of coaching, and principal leader identity construction. The findings supported the following conclusions: (a) Participants’ experiences of coaching were inconsistent with the coaching literature; (b) The impact of coaching was shaped by perceived competencies of the coach and the structure of the coaching session; and (c) Participants’ leader identity construction was supported through the process of coaching. 相似文献
977.
Maria G. Bartolini Bussi 《Journal of Mathematics Teacher Education》2011,14(2):93-112
In this article, I discuss a case of pre-primary and primary school teacher education concerning place value in number representation.
In primary school (in Italy, in grades 1 and 2), the topic is usually introduced by means of manipulatives (for instance,
abaci and base ten blocks). But it is well known that no artefact is transparent for mathematical meaning, unless the social
practices of the mathematics classroom, initiated by the teacher, are effective. The aim of this study is to report on tasks
given in a four-session (16 h) workshop for 27 prospective pre-primary and primary school teachers, where the use of artefacts
in learning place value in base ten was tackled, within a suitable theoretical framework. Different sessions of the workshop
are analysed, focusing on tasks related to different components of mathematics knowledge for teaching. Effectiveness for professional
growth is reported, quoting documents written by students and by external evaluators. In a final paragraph, the implication
for pre-primary school teacher education is addressed. 相似文献
978.
This study engages public services librarians and librarians in administrative or managerial positions in a conversation about LGBTQ student needs. Using a sample from the Campus Pride Index’s Best 25 LGBTQ-friendly colleges and universities, the researchers gathered information regarding outreach, collections, facilities, services, and policies for LGBTQ students. The results of this survey suggest that, while there is a great deal of support for LGBTQ students among librarians, the Campus Pride criteria is not entirely being met. There is an unclear delineation between the role of the library in promoting LGBTQ friendliness, and the role of the larger university, which may be related to the uncertain position of the library in the campus environment. However, the empathy that librarians in both decision and non-decision making roles have towards LGBTQ students opens up the possibility of deeper conversations and proactive, innovative support services in the future. 相似文献
979.
980.