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Birgit Angelika Schmidt Martin Andreas Ziemann Simone Pentzien Toralf Gabsch Werner Koch Jörg Krüger 《文物保护研究》2016,61(2):113-122
A great number of Central Asian wall paintings, archeological materials, architectural fragments, and textiles, as well as painting fragments on silk and paper, make up the so called Turfan Collection at the Asian Art Museum in Berlin. The largest part of the collection comes from the Kucha region, a very important cultural center in the third to ninth centuries. Between 1902 and 1914, four German expeditions traveled along the northern Silk Road. During these expeditions, wall paintings were detached from their original settings in Buddhist cave complexes. This paper reports a technical study of a wall painting, existing in eight fragments, from the Buddhist cave no. 40 (Ritterhöhle). Its original painted surface is soot blackened and largely illegible. Grünwedel, leader of the first and third expeditions, described the almost complete destruction of the rediscovered temple complex and evidence of fire damage. The aim of this case study is to identify the materials used for the wall paintings. Furthermore, soot deposits as well as materials from conservation interventions were of interest. Non-invasive analyses were preferred but a limited number of samples were taken to provide more precise information on the painting technique. By employing optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, micro X-ray fluorescence spectroscopy, X-ray diffraction analysis, and Raman spectroscopy, a layer sequence of earthen render, a ground layer made of gypsum, and a paint layer containing a variety of inorganic pigments were identified. 相似文献
154.
Comparison of oil and egg tempera paint systems using time-of-flight secondary ion mass spectrometry
Zachary E. Voras Kristin deGhetaldi Brian Baade Eric Gordon Glenn Gates Thomas P. Beebe 《文物保护研究》2016,61(4):222-235
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is quickly becoming a critical tool in the field of art conservation. This technique provides high-resolution spatial maps of both inorganic and organic components located within cross-sectional samples collected from works of art. With recent advances in surface analysis, ToF-SIMS can now be used to identify specific amino acids present in protein-containing materials as well as fatty acids in drying oils. For example, the detection of the ion fragment associated with the amino acid hydroxyproline can be used to confirm the use of animal glue in a paint sample. As an analytical technique, ToF-SIMS avoids the need for derivatization/silylation reagents, with no interference by the presence of pigments. Furthermore, the layered systems that are often encountered in historical paint samples remain intact throughout the analytical procedure. This allows for the co-localization of organic and inorganic species in specific layers (e.g. egg yolk paint atop a glue ground). Because of this ability to localize the analytical signal to approximately 6?µm or less, the mass spectral information can be used to produce mass-resolved and spatially-resolve images which can be correlated to previous studies of the same samples. In this study, ToF-SIMS was used to analyze a paint cross section obtained from a painting attributed to Raphael, and another from a painting by the Sienese artist Matteo di Giovanni. 相似文献
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This paper explores the awareness of the young German and Norwegian participants in the Youth Olympic Games (YOG) of the additional educational mission of this new event, implemented by the International Olympic Committee. Among the questions considered are whether the nature of the event contradicts its claimed intention to focus on both competition and education. Data were collected through a set of interviews with young German and Norwegian athletes at the Singapore YOG in the summer of 2010 and the Innsbruck YOG in the winter of 2012. The findings revealed (1) a focus on elite sport by athletes and their coaches, while the educational aims were considered secondary; (2) that it was problematic for the young participants to focus on education in a high-performance event. The overall conclusion was that the YOG have had only limited success in achieving the educational ambitions of the Olympic Movement. 相似文献
157.
Daan Van De Pol Sena Alaeikhanehshir Mario Maas P. Paul F.M. Kuijer 《Journal of sports sciences》2016,34(12):1141-1147
The prevalence of ischaemia-related symptoms is remarkably high among elite indoor volleyball players. Since the exposure to sport-specific demands may be higher in beach volleyball compared to indoor volleyball, the aim of this study was to assess the prevalence of ischaemia-related symptoms and associated risk factors among world-class beach volleyball players. Therefore, a questionnaire survey was performed among beach volleyball players active during the 2013 Grand Slam Beach Volleyball in the Netherlands. In total, 60 of the 128 beach volleyball players (47%) participated: 26 males and 34 females from 17 countries. The self-reported prevalence of cold or blue or pale digits in the dominant hand during or immediately after practice or competition was 38% (n = 23). Two risk factors were independently associated with symptoms of blue or pale digits: more than 14 years playing volleyball (odds ratio (OR) 4.42, 90% confidence interval (90% CI) 1.30–15.07) and sex (female) (OR 4.62, 90% CI 1.15–18.57). In conclusion, the prevalence of symptoms associated with digital ischaemia is high among international world-class beach volleyball players. Female sex and the length of the volleyball career were independently associated with an increased risk of ischaemia-related symptoms. The high prevalence of these seemingly innocuous symptoms and possible associated risk factors warrant regular monitoring since early detection can potentially prevent thromboembolic complications and irreversible tissue damage. 相似文献
158.
Research examining our ability to avoid obstacles in our path has stressed the importance of visual input. The aim of this study was to determine if athletes playing varsity-level field sports, who rely on visual input to guide motor behaviour, are more able to guide their foot over obstacles compared to recreational individuals. While wearing kinematic markers, eight varsity athletes and eight age-matched controls (aged 18–25) walked along a walkway and stepped over stationary obstacles (180° motion arc). Visual input was manipulated using PLATO visual goggles three or two steps pre-obstacle crossing and compared to trials where vision was given throughout. A main effect between groups for peak trail toe elevation was shown with greater values generated by the controls for all crossing conditions during full vision trials only. This may be interpreted as athletes not perceiving this obstacle as an increased threat to their postural stability. Collectively, findings suggest the athletic group is able to transfer their abilities to non-specific conditions during full vision trials; however, varsity-level athletes were equally reliant on visual cues for these visually guided stepping tasks as their performance was similar to the controls when vision is removed. 相似文献
159.
Given that physical activity (PA) tends to decrease with age during adolescence, addressing factors that affect change is important. This study examined the similarity and interdependence of PA as influenced by psychosocial factors among adolescent best friend dyads. A total of 660 adolescents, representing 330 best friend dyads, completed questionnaires with regard to PA, sitting time, perceived exercise benefits and barriers, physical self-perception and social support for PA. Dyads were also identified as reciprocal and non-reciprocal best friends; reciprocal means that both considered each other best friends and non-reciprocal were those in which only one considered the other a best friend. Data were analysed using a hierarchical linear model framework. Results indicated significant similarities between reciprocal best friend dyads for PA and sitting time, and for sitting time in non-reciprocal best friends (P values <.01). Psychosocial variables were associated with PA in reciprocal best friend dyads and with sitting time in reciprocal and non-reciprocal best friend dyads. Best friend gender, regular sports practice of the person, perceived exercise barriers of the best friend and best friend social support were the best predictors for PA. 相似文献
160.
Daniel Link Otto Kolbinger Hendrik Weber Michael Stöckl 《Journal of sports sciences》2016,34(24):2312-2320
ABSTRACTThis study investigates the spatial relationship of performance variables for soccer free kicks. In order to suggest ways in which players might optimise their performance, we collected data from free kicks (<35 m to goal line) of two German Bundesliga seasons (2013/14, 2014/15) (n = 1624). In the analysis, we applied the ISO-map approach using colour gradients to visualise the mean values of a variable on a 2D-map of the pitch. Additionally, variograms were used to describe the degree of spatial dependence of the free kick variables. Results show that DENSITY, TYPE OF PLAY, PLAYERS IN WALL, DISTANCE TO WALL and RULE VIOLATION were strongly spatially dependent. Centrality and proximity to the goal increased the variables PLAYERS IN WALL, RULE VIOLATIONS and INTERRUPTION TIME, and the ratio of goals scored increased from 5.9% (central far) to 10.9% (central near). In 70.9% of the shots, players preferred a switched laterality, which did not result in a higher success rate. Furthermore, there was no statistical advantage for the defensive team when DISTANCE TO WALL was below 9.15 m or when there was a RULE VIOLATION. Crosses had a success rate (i.e., first controlled ball contact after the cross) of 20.8%. Played with natural laterality, they were 5% more successful than with switched laterality. Crosses from the right side outside the penalty box were 10% more successful than from the left side. Therefore, it might be worthwhile practising the defence of balls coming from this side. 相似文献