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ABSTRACT This article presents historical and scientific analysis, as well as the conservation treatment of a newly rediscovered Roman wall painting fragment, now in the collection of the Harvard Art Museums. Although the piece has not previously been published, it was among a group of fragments removed from a Roman villa near Boscotrecase in southern Italy, an area that has been key to the study of Roman wall painting and other decoration. Technical imaging confirms the use of painting techniques consistent with other high-quality paintings in the area. Materials analysis revealed a palette consistent with published findings of Roman wall paintings, including abundant use of Egyptian blue and green earth. Of interest was the use of Egyptian blue as an optical brightener in select white passages. Despite the high quality of the painting, no cinnabar was present, and all red passages were achieved using hematite. Multiple different white minerals were identified including calcite, aragonite, and gypsum. The widespread presence of gypsum is unusual and may point to alteration. 相似文献
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Cyril Rebetez Mireille Bétrancourt Mirweis Sangin Pierre Dillenbourg 《Instructional Science》2010,38(5):471-485
Animated graphics are extensively used in multimedia instructions explaining how natural or artificial dynamic systems work.
As animation directly depicts spatial changes over time, it is legitimate to believe that animated graphics will improve comprehension
over static graphics. However, the research failed to find clear evidence in favour of animation. Animation may also be used
to promote interactions in computer-supported collaborative learning. In this setting as well, the empirical studies have
not confirmed the benefits that one could intuitively expect from the use of animation. One explanation is that multimedia,
including animated graphics, challenges human processing capacities, and in particular imposes a substantial working memory
load. We designed an experimental study involving three between-subjects factors: the type of multimedia instruction (with
static or animated graphics), the presence of snapshots of critical steps of the system (with or without snapshots) and the
learning setting (individual or collaborative). The findings indicate that animation was overall beneficial to retention,
while for transfer, only learners studying collaboratively benefited from animated over static graphics. Contrary to our expectations,
the snapshots were marginally beneficial to learners studying individually and significantly detrimental to learners studying
in dyads. The results are discussed within the multimedia comprehension framework in order to propose the conditions under
which animation can benefit to learning. 相似文献
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Cooper E 《Medical reference services quarterly》2008,27(1):97-103
There are many online drug information resources available from commercial vendors, but they are often too costly for hospital librarians on a limited budget. Several free Internet options available from a variety of commercial, government, U.S., foreign, professional, and consumer sites are described here. 相似文献
128.
Denny Wells Jacqueline Alderson Valentina Camomilla Cyril Donnelly Bruce Elliott Andrea Cereatti 《Journal of sports sciences》2019,37(5):515-524
Magnetic and inertial measurement units (MIMUs) may provide an accessible, three-dimensional, in-field alternative to laboratory-restricted marker-based motion capture. Existing upper limb MIMU models have predominantly been validated with low-velocity motion and their suitability for use with sport-based movements remains relatively untested. We propose a MIMU system approach to enable the estimation of anatomically meaningful and participant-specific elbow kinematics with considerations for use with cricket bowling. A novel standardised elbow reference posture of 90 degrees flexion and 0 deg pronation, and functional definition of elbow joint axes of rotation calibrated the MIMU method model before it was validated across three experiments: (1) simple elbow rotations with a mechanical linkage; (2) low-velocity elbow rotations in human participants; and (3) low-medium velocity sport-based movements in human participants. The proposed MIMU method demonstrated high elbow kinematic measurement agreement when compared with a criterion measure across all three conditions. However, during experiment 3, sensor components neared their measurement capacity and the MIMU method elbow flexion measurement variability increased. We conclude that the proposed MIMU method can estimate anatomically referenced, participant-specific joint angles, however, the hardware specifications of currently available systems may limit application in high-velocity/acceleration situations, preventing the measurement of cricket bowling in-field for now. 相似文献
129.
Variables associated with disrupted placement in a select sample of abused and neglected children 总被引:1,自引:0,他引:1
The purpose of this study was to examine the placement history of 172 abused and/or neglected children who had been placed in a residential home for maltreated children. Data were collected on the child's placement history (i.e., number of placements, time in transition, and placement rate) and also on child and family characteristics. Pearson correlation coefficients were run between child and family variables and each of the three placement history variables. In addition, t-tests were also used as a method of analysis. Results indicated that children with the following characteristics or life circumstances experienced the more disruptive experience while in foster care: children having severe behavior problems; children who were very young when first removed from their natural home; and children having drug addicted and/or alcoholic parents. Implications of these findings indicate social workers and judges need to be alert to the potential for system abuse of children in foster placement, responsible long-term planning for any child in foster care is critical, and those involved in therapeutic treatment for abused/neglected children should be attentive to the child's placement history. 相似文献
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