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991.
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
992.
To examine the development of look duration as a function of age and stimulus type, 14- to 52-week-old infants were shown static and dynamic versions of faces, Sesame Street material, and achromatic patterns for 20 s of accumulated looking. Heart rate was recorded during looking and parsed into stimulus orienting, sustained attention, and attention termination phases. Infants' peak look durations indicated that prior to 26 weeks there was a linear decrease with age for all stimuli. Older infants' look durations continued to decline for patterns but increased for Sesame Street and faces. Measures of heart rate change during sustained attention and the proportion of time spent in each phase of attention confirmed infants' greater engagement with the more complex stimuli. 相似文献
993.
The associative learning effect called blocking has previously been found in many cue-competition paradigms where all cues
are of equal salience. Previous research by Hall, Mackintosh, Goodall, and dal Martello (1977) found that, in animals, salient
cues were less likely to be blocked. Crucially, they also found that when the to-be-blocked cue was highly salient, the blocking
cue would lose some control over responding. The present article extends these findings to humans and suggests that shifts
in attention can explain the apparent loss of control by the previously learned cue. A connectionist model that implements
attentional learning is shown to fit the main trends in the data. Model comparisons suggest that mere forgetting, implemented
as weight decay, cannot explain the results. 相似文献
994.
OBJECTIVE: The purpose of this study was to determine the level of inter-rater reliability of the Illinois Structured Decision Support Protocol by examining the level of Child Protective Services (CPS) caseworkers' agreement regarding state interventions. The Protocol was designed to guide CPS workers to consistent decisions related to the level of state intervention in child maltreatment cases. METHOD: Forty-one workers recruited from three CPS field offices in Illinois participated in this study by assessing three cases using the Illinois Structured Decision Support Protocol. The three cases were developed based on actual cases investigated by the agency. The kappa statistic was used to calculate the level of workers' agreement. RESULTS: The result showed a weak reliability (kappa=.29). Further analysis showed that workers identified a wide range of risk factors and differing levels of intervention for each identified risk factor even among the workers who made the same final decisions. CONCLUSIONS: Decision support protocols are developed to provide systematic structures for workers' decision-making. However, this study suggested that workers demonstrated a low level of agreement on such a protocol. Several suggestions for developing more reliable computerized protocols include: more specified inquiries with criteria to assess the range of risk for a factor, consideration of interactions among risk factors, assessment of family strengths, and having the final decision made by a computerized program. 相似文献
995.
This paper reports on research on the attitudes of a differentiated sample of students to Catholic schools in general and religious education in particular. Core Catholic youth are described, following Fulton et al. (2000: Young Catholics at the New Millennium, Dublin, University College Press), as individuals who have an existing connection with the parish community. Some results that emerge from 58 in‐depth interviews with 14‐ and 15‐year‐old core Catholics are that they value their time in Catholic schools, feel that they are in a safe environment and are not well networked with others of a similar background. Attitudes to religious education by core Catholic youth are described as weak positive. Religious education is not unpopular but is not seen as a discipline that helps resolve some of the difficulties that they experience as young Catholics. These difficulties relate to trying to reconcile what they see as the conflict between the scientific and religious view of creation and many supernatural religious claims. 相似文献
996.
Lang AJ Laffaye C Satz LE McQuaid JR Malcarne VL Dresselhaus TR Stein MB 《Child abuse & neglect》2006,30(11):1281-1292
OBJECTIVE: Women with histories of childhood maltreatment (CM) have higher rates of physical health problems and greater medical utilization compared to women without abuse histories. This study examined whether current post-traumatic stress disorder (PTSD) symptoms mediate the relationship between CM and indicators of physical health and medical utilization in female veterans. METHOD: Respondents were 221 female veterans (56% of the potential sample), who received medical care from the San Diego VA Healthcare System during a 12-month period. Respondents provided self-report information about CM, PTSD symptoms, use of pain medication, and physical symptoms and functioning. Additional information about medical utilization was extracted from respondents' medical charts. Regression-based models were conducted to test whether PTSD symptoms mediate the relationships between CM and physical symptoms and between CM and medical utilization. RESULTS: Emotional abuse was associated with poorer role-physical functioning, increased bodily pain and greater odds of using pain medication in the past 6 months. Physical abuse was associated with poorer general health. Contrary to prediction, emotional neglect was associated with better role-physical functioning, and CM was not associated with increased healthcare utilization. PTSD was shown to mediate the relationship between emotional and physical abuse and health outcomes. CONCLUSIONS: PTSD, or psychopathology more generally, appears to be an important factor in the negative health impact of CM. Given that several empirically supported interventions are available for PTSD, there may be physical health benefits in early identification and treatment of psychopathology related to CM. 相似文献
997.
998.
BACKGROUND: The National Library for Health offers a comprehensive searchable database of nationally approved clinical guidelines, called the Guidelines Finder. This resource, commissioned in 2002, is managed and developed by the University of Sheffield Health Sciences Library. METHODS: The authors introduce the historical and political dimension of guidelines and the nature of guidelines as a mechanism to ensure clinical effectiveness in practice. The article then outlines the maintenance and organisation of the Guidelines Finder database itself, the criteria for selection, who publishes guidelines and guideline formats, usage of the Guidelines Finder service and finally looks at some lessons learnt from a local library offering a national service. CONCLUSIONS: Clinical guidelines are central to effective clinical practice at the national, organisational and individual level. The Guidelines Finder is one of the most visited resources within the National Library for Health and is successful in answering information needs related to specific patient care, clinical research, guideline development and education. 相似文献
999.
1000.