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21.
The subject of the research is an oil painting entitled Idyll created using an unusual technique. The painting layer was applied on canvas covered with photosensitive medium on which a photograph was developed. The results of the examination of Idyll in the context of its attribution to Henryk Siemiradzki (1843–1902) are discussed. Its atypical technology and the possibility of the artist having used the photographic technique are also considered. X-ray fluorescence spectroscopy, infrared spectroscopy, and scanning electron microscopy were performed to establish the technique and to characterize the pigments and materials used in the painting. The identified pigments and the information provided by analytical photography (UV, X-ray images) were compared with the results of the detailed examination of 56 of Siemiradzki’s oil paintings. Performed analyses revealed that the majority of the features identified in Idyll point to Henryk Siemiradski’s technique.  相似文献   
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Key points

  • Early career researchers (ECRs) consider journals the central form of communication – but are concerned about pressure to publish.
  • ECRs want to share but currently accept the closed publishing system because of the need to build a traditional reputation.
  • ECRs know – and appear to care – little about publishers but trust them as publishing and reviewing facilitators.
  • Editors are criticized for not managing peer review with better selection of reviewers.
  • Megajournals are not seen as the future journal form and criticized for lack of selectivity.
  • ECRs want open access/science in principle but are circumspect about their contribution to it.
  • ResearchGate is a key force for change as ECRs consider it a mainstay communication and reputation platform.
  相似文献   
23.
The drying shrinkage accumulation from exposure of freshly prepared gesso layers to relative humidity (RH) cycles was determined to elucidate the mechanism of craquelure pattern formation on panel paintings. The progresive drying shrinkage of the gesso is observed only under the cycles going to high RH levels which bring about transitions from brittle to ductile state of the material. The first incidence of fracture on the gesso layers occurred after a limited number of cycles ranging between a few and 100 for a range of layer thickness between 0.5 and 1?mm. The craquelure patterns stabilised also after a limited number of cycles (30 for the 1-mm thick layer). Upon increase in the gesso layer thickness, the strength of the layer is reduced and the spacing of shrinkage fractures increases. The study demonstrated that craquelure patterns, mimicking historical ones, can be realistically produced in laboratory conditions. Such studies would provide useful information for preparing specimens simulating historic panel paintings and would inform the current efforts on automatic, computer-aided classifications of crack formations on paintings.  相似文献   
24.
Presents findings from a study into the attitudes and practices of pandemic-era early career researchers (ECRs) in regard to obtaining access to the formally published scholarly literature, which focused on alternative providers, notably ResearchGate and Sci-Hub. The study is a part of the Harbingers project that has been exploring the work lives and scholarly communication practices of ECRs in pre-pandemic times and during the pandemic, and utilizes data from two rounds of interviews with around 170 ECRs from the sciences and social sciences in eight countries. Findings show that alternative providers, as represented by ResearchGate and Sci-Hub, have become established and appear to be gaining ground. However, there are considerable country- and discipline-associated differences. ECRs' country-specific level of usage of the alternative providers is partly traceable to the adequacy of library provisions, although there are other factors at play in shaping ECRs' attitudes and practices, most notably convenience and time saving, as well as the fact that these platforms have become embedded in the scholarly dashboard. There is a dearth of evidence of the impact of the pandemic on ECRs' ways of obtaining scholarly papers.  相似文献   
25.
The precise etiology and reasons for the increase in incidence of autoimmune disorders still remain unclear, and although both genetic and environmental factors have been proven to shape individual predisposition, it is not known which of the factors, if not both, is responsible for the boom observed during the last decades. In order to establish whether a higher frequency of autoimmune-predisposing alleles may explain this increase we took advantage of ancient DNA methodology to establish the genetic predisposition, conferred by cytotoxic T lymphocyte associated antigen-4 (CTLA4) +49A/G and human leukocyte antigens (HLA) DQBI^57, in population inhabiting Poland in the Middle Ages. After successful typing of 42 individuals from a 12th-14th's century archeological burial site, we found that frequencies of the predisposing alleles in the medieval population were higher than they are at present, suggesting thus that the recently observed incidence increase results most probably from factors of other than genetic nature.  相似文献   
26.
目的:评估可溶性血管细胞间黏附分子(s VCAM-1)、可溶性细胞间黏附分子(s ICAM-1)、可溶性选择素E和可溶性血栓调节蛋白在血糖控制良好和不受控制的2型糖尿病患者中的水平。创新点:对2型糖尿病患者的血管内皮炎症标记物进行评估。方法:62例糖尿病患者分成两组:第一组包括35个血糖控制良好的糖尿病患者,第二组包括27个未控制血糖并伴有微蛋白尿的糖尿病患者。对照组由25名健康志愿者组成。测定血浆中s VCAM-1、s ICAM-1、可溶性选择素E和可溶性血栓调节蛋白的浓度,同时测定血清肌酐及血浆中空腹血糖和糖化血红蛋白(Hb A1c)的浓度。结论:与血糖控制良好的糖尿病组相比,未控制血糖组具有相对低的ICAM-1水平和更高的VCAM-1水平。未控制血糖组中患者的糖化血红蛋白和ICAM-1之间呈正相关,肾小球滤过率和可溶性选择素E之间呈正相关,而肌酐和ICAM-1之间呈负相关。研究证实2型糖尿病的发病机理中炎症过程的出现与血管内皮功能受损有关。未受控制的高血糖对粘附分子的反向作用表明,在糖尿病的并发症中VCAM-1和ICAM-1具有不同功能。  相似文献   
27.

Background

Numerous data suggest that aerobic-type exercise improves lipoprotein-lipid profiles, cardiorespiratory fitness and body composition in young women. The aim of this study was to evaluate the biological response to high-low impact aerobic fitness among young women.

Materials and methods

Thirty-four young women aged 22 (19-24) years were divided into three groups: underweight (N = 10), normal weight (N = 12) and overweight (N = 12). Aerobic capacity, anthropometry and body composition together with complete blood count and lipid profile were determined before and after completion of a 12-week-long training period.

Results

The training programme caused a significant decrease in weight (by 4.3 kg, P = 0.003), body mass index (by 1.3 kg/m2, P = 0.003), free fat mass (by 2.1 kg, P = 0.002), total body water (by 0.4 kg, P = 0.036), percentage of fat (by 3 percent points, P = 0.002), all analyzed skinfolds thicknesses, as well as the lipid profile in overweight group, and no changes in normal weight group. Significant changes in weight (by 4.2 kg, P = 0.005), body mass index (by 0.9 kg/m2, P = 0.005), crus skinfold thickness (by 3.3 mm, P = 0.028), and in maximum oxygen uptake (by 2.49 mL/kg/min; P = 0.047) were observed among underweight women. No change in total blood count was observed in all groups.

Conclusion

Twelve-week-long fitness training programme of two alternating styles (low and high impact) has a beneficial effect on overweight young women.Key words: body composition, physical fitness, overweight, women  相似文献   
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