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991.
The renaissance frescoes of the metropolitan cathedral of Valencia, located at the vault of the apse, were restored in 2006. We describe a microclimate monitoring system that was implemented for the preventive conservation of the paintings. It is comprised by a set of temperature and relative humidity sensors positioned at different points of the vault. This system is rather unique because some of these sensors were inserted inside the paintings during the restoration process. A principal components analysis was applied to the data of relative humidity recorded in February 2007. The analysis was repeated in three additional months of 2007. The resulting loading plots highlight the most relevant similarities and dissimilarities among sensors. These plots can be considered as some sort of control maps that could be used to detect abnormal conditions in the future. Actually, moisture problems at certain zones of the frescoes are causing the formation of efflorescence, and the sensors located close to these zones are the ones recording the highest values of relative humidity. 相似文献
992.
Pedro Martín Lerones José Llamas Fernández Álvaro Melero Gil Jaime Gómez-García-Bermejo Eduardo Zalama Casanova 《Journal of Cultural Heritage》2010,11(1):1-9
On many occasions, the graphic information handled by people working in the cultural heritage sector is still bidimensional. Layouts showing elevations and cross sections are the most widespread tools. However, there is an increased need for carefully detailing the complexity of valuable sites with an improved accuracy. This implies the measuring and handling of three-dimensional data, using both commercial and turn-key hardware and software solutions. Taking the usual traditional process as a reference, in the present paper a new effective methodology for carrying out computer assisted delineation of layouts from cultural heritage sites, using 3D digital models, is described. The proposed procedure has been tested in five intervention projects on representative churches within the “Merindad de Aguilar de Campoo” medieval area, in the north of Spain.1 This area has the largest collection of Romanesque art in the world, and is currently under European Heritage Site and World Heritage Site declaration process by the UNESCO. 相似文献
993.
Ramón Zárraga Jorge Cervantes Carmen Salazar-Hernandez George Wheeler 《Journal of Cultural Heritage》2010,11(2):138-144
Hybrid stone consolidants prepared from tetraethoxysilane (TEOS) and α,ω-hydroxyl-terminated polydimethylsiloxane (PDMS-OH) have been considered as one of the most promising approaches to improve the effectiveness of traditional alkoxysilane-based formulations. They have emerged as response to the negative reports commonly found in the literature: the resulting silica gel phase (SiO2) tends to develop fractures and fissures inside the stone as the gel shrinks during the drying stage. In this work, we employed SEM, solid-state 29Si NMR spectroscopy and compressive tests to characterize SiO2-PDMS hybrid gels. We report the morphological characteristics exhibited by gels prepared in vitro and in situ. It was found an appreciable reduction of gel fracture for hybrids prepared from 5% w/w of PDMS. As TEOS polycondenses, PDMS-OH is chemically incorporated into the gel matrix via Si-O-Si bonds. The inclusion of these elastic chains provides the necessary flexibility to resist the stress imposed by capillary pressure. Additionally, an important hydrophobic character is imparted to the stone. 相似文献
994.
This paper provides an introduction to the Mexican-American culture, describing (1) cultural diversity and linguistic policies in the United States; (2) cultural and linguistic studies that have examined the backgrounds of Mexican-American individuals; (3) the characteristics of this population; (4) issues on discrimination and human relations; (5) the socioeconomic factors that Mexican-American individuals encountered due to their lack of education; and (6) the predominance of poorly paid and undereducated unskilled workers. Although many Mexican Americans have moved up the social ladder to the middle class, others have not. However, they have a richness of language and culture to share with the school. 相似文献
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998.
Jeremy Kilpatrick Edmund King Pierre Ferran Nicolas Hans A. Harry Passow Graeme Kemelfield Eric Ashby Mark Blaug Franklin Parker F. Walz Fritz Borinski Russell F. Farnen Robert F. Lawson Horst Magdeburg Robert J. Havighurst David A. Walker Alexandre Vexliard Josef Havlíček Otto Peters Hans Tutken M. A. Boisard George Z. F. Bereday 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1969,15(1):83-120
999.
Leonor Guin Anna Soler Rosa María Lpez Sonia Pajares Jos Manuel Gonzlez de Aledo Ana Argudo-Ramírez Jos Luis Marín Judit García-Villoria ngeles Sahuquillo Luisa Alvarez 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2022,32(3)
IntroductionTo ensure the quality of the new-born screening (NBS), our laboratory reviewed the analytical procedure to detect subjective steps that may represent a risk to the patient. Two subjective activities were identified in the extra-analytical phases: the classification of dried blood spots (DBS) according to their quality and the assignment of haemoglobin patterns. To keep these activities under control, inter-rater studies were implemented. This study aimed to evaluate the inter-rater reliability and the effectiveness of the measures taken to improve the agreement between observers, to assure NBS results’ quality.Materials and methodsDried blood spots specimens were used for the inter-rater studies. Ten studies were performed to assess DBS quality classification, and four to assess the assignment of haemoglobin patterns. Krippendorff’s alpha test was used to estimate inter-rater reliability. Causes were investigated when alpha values were below 0.80.ResultsFor both activities, the reliability obtained in the first studies was inadequate. After investigation, we detected that the criterion to classify a DBS as scant was not consolidated, and also a lack of consensus on whether or not to report Bart’s haemoglobin depending on its percentage. Alpha estimates became higher once the training was reinforced and a consensus about the appropriate criteria to be applied was reached.ConclusionInter-rater reliability assessment helped us to ensure the quality of subjective activities that could add variability to NBS results. Furthermore, the evolution of the alpha value over time allowed us to verify the effectiveness of the measures adopted. 相似文献
1000.
Cristóbal Rodríguez Adam Amador B. Abigail Tarango 《Equity & Excellence in Education》2016,49(2):228-240
The purpose of our study is to investigate reform policy, specifically a proposed third grade reading retention policy within the Borderlands. Under this policy, students not performing proficiently on the third grade reading standardized exam will be automatically retained in the third grade. The research methods and approach used in this study include an equity analysis formed by combining two steps across a Borderland county in New Mexico. The first step is a regression analysis to answer if access to early childhood education and access to highly qualified teachers inform differences in third grade reading scores, and the second step uses a LatCrit informed Spatial Analysis to create an equity index, to see how equity varies across the spaces of elementary schools. This allows us to essentially map Third Grade Reading Retention Reform Policy in the Borderlands. The setting of the study is in the U.S. Southwest Borderlands, specifically Doña Ana County, which borders Texas and Mexico, in southern New Mexico. Up to a quarter of the population is under the age of 18, two thirds (66.6%) of the population is Latino, and half of the population speaks a language other than English at home. Implications from this study include, for policy makers, policy considerations that come from a non-deficit thinking perspective and focus on systemic considerations to improving educational equity. Given that the setting demographically mirrors much of the state of New Mexico, as well as demographic shifts across communities throughout the U.S., this study provides further considerations for key systemic changes to improving academic measures like reading scores. 相似文献