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1.
Alberta Silvestri Serena Tonietto Francesco D’Acapito Gianmario Molin 《Journal of Cultural Heritage》2012,13(2):137-144
This work reports mainly the results of an X-ray Absorption Spectroscopy (XAS) study carried out on coloured glass tesserae from the palaeo-Christian mosaic which decorated the votive chapel of St. Prosdocimus (Padova) until its replacement with the current frescoes of Renaissance age, and which is one of the only two known mosaics in the Veneto region (Italy). The study aims at clarifying how the different local structure, oxidation state and quantity of copper influenced colour. Analysis of high-resolution Cu-K edge X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) spectra showed that copper is present as cuprite (Cu2O) in orange samples and as metallic copper in red and brown ones. These phases are responsible for both the colour and opacity of the samples. In addition, Cu1+ ions linked to the oxygen atoms of the glass framework were identified in ratios of about 60% and 30% of total copper in orange and red/brown samples, respectively. In blue and green samples, copper is dispersed in the glass matrix as a mixture of Cu1+ and Cu2+ ions, and no crystalline phases are visible. In this context, the Cu1+ and Cu2+ contents in glass were also quantified thanks to suitable standards, demonstrating that, when Cu2+ is the main chromophorous ion, colour intensity is directly correlated to its content in the glass. In particular, in green and blue samples, coloured by copper, Cu2+ content varies from 26% to 56% of total copper, and the higher contents of Cu2+ are shown by more intensely coloured samples. It should be stressed here that the green colour of the analysed tesserae is given by the physical interaction of blue colour, due to Cu2+ ions, and yellow colour, due to Pb antimonates used as opacifiers. 相似文献
2.
Kamilla B. Kalinina Ilaria Bonaduce Maria Perla Colombini Irina. S. Artemieva 《Journal of Cultural Heritage》2012,13(3):259-274
This paper presents the first extensive investigation of the composition of both the organic and inorganic media used by Lorenzo Lotto, one of the outstanding artists of the Italian Renaissance in the early 16th century. By investigating four paintings from The State Hermitage Museum collection (Saint-Petersburg, Russia), new insights into the artist's painting techniques were obtained, which contribute to our understanding of the transition from egg tempera to oil painting techniques that took place in Italian paintings between the 15th to the mid 16th century. Inorganic materials were determined using SEM-EDX and PLM, revealing information on the artist's palette. Of particular note was the powdered colourless glass found in the priming layer of the Madonna delle Grazie, which was most likely used as dryer. Organic materials were analysed in individual paint layers using GC-MS, and revealed a mature use of drying oils as paint binders, skilfully mixed with other organic materials and inorganic driers, to obtain the desired aesthetical and technical qualities of the paint. The study revealed that Lotto used the tempera grassa technique through most of his creative life. 相似文献
3.
Dina Guglielmi Ilaria Bruni Silvia Simbula Franco Fraccaroli Marco Depolo 《European Journal of Psychology of Education - EJPE》2016,31(3):323-340
Despite the growing body of research on work engagement, little is known about what drives work engagement among different age cohorts. This study aims to investigate whether engagement varies across age cohorts and examine the job resources that foster teacher engagement. A questionnaire was distributed to 537 teachers who were employed in elementary, lower and upper secondary school. Findings show that work engagement did indeed vary across the diverse age group and is influenced by different resources. In line with previous studies, data revealed that the engagement of younger teachers is driven by the opportunity for development and interaction with colleagues, while older employees appreciate the opportunity to see their competencies acknowledged. What is most noteworthy is the opportunity to design practices and to provide every age group with the appropriate set of motivators. 相似文献
4.
Business cycles modify firms’ incentives to innovate and the direction of innovation. By introducing a new measure of patent unconventionality this paper explores the impact of the business cycle on firms’ technological search strategies. We find that during upturns firms generate inventions characterized by a higher level of technological unconventionality. We also find that financially resilient and diversified firms produce more unconventional patents. While patent unconventionality is associated with technological impact and market value, firms extract more value by investing in unconventional inventions in downturns. 相似文献
5.
Lisa Silvestri 《Visual Communication Quarterly》2014,21(2):106-118
When U.S. troops in Iraq and Afghanistan filter their war experiences through visual aesthetics characteristic of contemporary mobile messaging culture, they produce a new visual discourse for war in the Internet age. A critical reading of 250 Facebook photos reveals an emphasis on colloquial representations of young adult life: hanging out, goofing off, playing games, and wearing costumes. For example, one image depicts two Marines in full desert camouflage posing for a picture while wearing skeleton masks. The Marine on the left looks down at his digital camera, either reviewing a photo or getting ready to hand it off to the “shooter.” The gear in the photo (masks aside) suggests that they are prepared for a combat scenario. Mortars and rockets could hit their base at any moment. The silliness and nonchalance captured in the photo seems antithetical to their physical locale, especially a condition of imminent danger. Most audiences would not recognize this as a combat scenario. Photos like this reflect the ways in which our shifting visual repertoire—with emphases on friendship, domesticity, and spontaneity—modifies visual discourses for contemporary war. 相似文献
6.
Vito N. Silvestri 《Communication Studies》2013,64(3):178-186
Roosevelt urged war preparation and active retaliation when neutral policies prevailed and when the mood of the nation was one of noninvolvement abroad. 相似文献
7.
Kathryn Anderson Samuel V. O. Prichard Jr. Vito Silvestri Howard Schwartz Bonnie J. Buenger J. A. Hendrix 《Communication quarterly》2013,61(3):51-54
FREE SPEECH: RESPONSIBLE COMMUNICATION UNDER LAW. By Robert M. O'Neil. Indianapolis, Indiana: The Bobbs‐Merrill Company, Inc., 1966; pp. viii 123+$1.25. THE MOYNIHAN REPORT AND THE POLITICS OF CONTROVERSY, by Lee Rainwater and William L. Yancey. Cambridge: MIT Press, 1967; pp. xvii+493. $3.95. VOICES OF CRISIS: VITAL SPEECHES ON CONTEMPORARY ISSUES, by Floyd W. Matson, New York: The Odyssey Press, Inc., 1967; pp. xi+304. THE BLACK POWER REVOLT. Edited by Floyd B. Barbour. Boston: Porter Sargent Publisher, 1968; pp. 287. $5.95 cloth; $2.95 paper. THE AGITATOR IN AMERICAN SOCIETY. By Charles W. Lomas. Englewood Cliffs, New Jersey: Prentice‐Hall, 1968; pp. viii+182. BLACK POWER: THE POLITICS OF LIBERATION IN AMERICA. By Stokely Carmichael and Charles V. Hamilton. New York: Vintage Books, 1967; pp. xii+ 198. Paper $1.95. REPORT OF THE NATIONAL ADVISORY COMMISSION ON CIVIL DISORDERS. New York: Bantam Books, 1968; pp. xi+609. Paper $1.25. 相似文献
8.
Ilaria Bordino Mounia Lalmas Yelena Mejova Olivier Van Laere 《Information Retrieval》2016,19(5):447-486
Search engines are increasingly going beyond the pure relevance of search results to entertain users with information items that are interesting and even surprising, albeit sometimes not fully related to their search intent. In this paper, we study this serendipitous search space in the context of entity search, which has recently emerged as a powerful paradigm for building semantically rich answers. Specifically, our work proposes to enhance an explorative search system that represents a large sample of Yahoo Answers as an entity network, with a result structuring that goes beyond ranked lists, using composite entity retrieval, which requires a bundling of the results. We propose and compare six bundling methods, which exploit topical categories, entity specializations, and sentiment, and go beyond simple entity clustering. Two large-scale crowd-sourced studies show that users find a bundled organization—especially based on the topical categories of the query entity—to be better at revealing the most useful results, as well as at organizing the results, helping to discover novel and interesting information, and promoting exploration. Finally, a third study of 30 simulated search tasks reveals the bundled search experience to be less frustrating and more rewarding, with more users willing to recommend it to others. 相似文献
9.
Ilaria Bonaduce Catharina Blaensdorf Patrick Dietemann Maria Perla Colombini 《Journal of Cultural Heritage》2008,9(1):103-108
The “Terracotta Army” is a worldwide known archaeological finding in China. It is a part of the burial complex of the emperor Qin Shihuangdi (259–210 BC), which is still under excavation and study. The fact that the sculptures, chariots and weapons of the First Chinese Emperor's Terracotta Army were originally all painted in bright colours is still not widely known. The chemical characterisation of the paint medium was performed through an analytical procedure based on GC-MS. The proteinaceous binder was identified for the first time through a desalting procedure used in proteomics. The identification of egg as a paint binder is extremely interesting in terms of the historical significance of the work of art itself and important in terms of the method of conservation. Moreover it represents one of the first steps towards an understanding of the painting technique used on ancient sculptures in China, of which – despite their fame – nothing is yet known. 相似文献
10.
Veronica Ornaghi Elisa Brazzelli Ilaria Grazzani Alessia Agliati Maria Lucarelli 《Early education and development》2017,28(4):396-414
Research Findings: Within the flourishing area of research demonstrating the efficacy of emotion-based interventions carried out by trained teachers in educational contexts in increasing children’s emotional skills, this study makes an original contribution to the existing literature by focusing on the effects of this kind of intervention on toddlers’ prosocial and aggressive behavior. Ninety-five 26- to 36-month-olds participated in a 2-month intervention in which trained teachers read emotion-based stories to small groups of children and then either involved them in conversations about emotions (experimental condition) or did not (control condition). Even after we controlled for age and general language ability, the children in the experimental condition were found to outperform the control group on measures of emotion knowledge and emotional-state talk. Furthermore, the intervention fostered gains in prosocial behavior, whereas it did not have a significant effect on the frequency of aggressive actions, which was lower at posttest in both groups. The positive effect of the training program on participants’ prosocial behavior was no longer significant when we controlled for gains in emotion knowledge and emotional-state talk. Practice or Policy: The results encourage the implementation of early educational programs focused on emotion knowledge in order to foster children’s prosocial behavior toward peers. 相似文献