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21.
David Nicholas Anthony Watkinson Abdullah Abrizah Cherifa Boukacem‐Zeghmouri Jie Xu Blanca Rodríguez‐Bravo Marzena Świgoń Eti Herman 《Learned Publishing》2018,31(3):249-253
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.
22.
Leszek Krzemień Michał Łukomski Łukasz Bratasz Roman Kozłowski Marion F. Mecklenburg 《文物保护研究》2016,61(6):324-330
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
23.
Eti Herman David Nicholas David Clark Chérifa Boukacem-Zeghmouri Blanca Rodríguez-Bravo Abdullah Abrizah David Sims Anthony Watkinson Jie Xu Galina Serbina Marzena Świgoń Hamid R. Jamali Carol Tenopir Suzie Allard 《Learned Publishing》2023,36(2):141-155
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
24.
Witas HW Jedrychowska-Dańska K Zawicki P 《Journal of Zhejiang University. Science. B》2007,8(7):512-514
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
25.
Dorota Kostrzewa-Nowak Robert Nowak Zbigniew Jastrz?bski Aleksandra Zar?bska Marta Bichowska Izabela Drobnik-Kozakiewicz ?ukasz Radzimiński Agata Leońska-Duniec Krzysztof Ficek Pawe? Ci?szczyk 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(1):103-113
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26.
27.
Aleksandra S. Panajotovi? Mihajlo ?. Stefanovi? Dragan Lj. Dra?a 《Journal of The Franklin Institute》2010,347(7):1242-1252
We study the performance of dual branch switch and stay combining (SSC) diversity receivers operating over correlated Rician fading channels, in the presence of correlated Rayleigh distributed cochannel interference (CCI). Fast convergent infinite series representations for both the joint probability density function (PDF) of the SSC input signal-to-interference ratios (SIRs) and the PDF of the SSC output SIR are derived. The last one is applied to semi-analytically study the average bit error probability (ABEP) of differential binary phase shift keying (DBPSK). Furthermore, the optimum switching threshold in the sense of minimum ABEP is obtained numerically and the effects of fading severity and branch correlation on both ABEP and optimum switching threshold are investigated. Numerical and simulation results are presented to support the mathematical analysis. 相似文献
28.
29.
This article focuses on the problems of adults who in secondary school were high ability learners. The main point of interest of the research presented here is job satisfaction among gifted people and their temperament structure. The authors are interested whether there exist correlations between the investigated variables both in the entire group of gifted individuals as well as in the subgroup of those gifted in the humanities and in the control group. The research results show that between the group of gifted people and the control group there appear significant differences in vigorousness (VG) and activity (AC). The studied groups differ as to the kind and extent of the fulfilment of expectations concerning professional career. Gifted individuals, in comparison to the control group, are more satisfied with their jobs. 相似文献
30.
Wincenty Okoń 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1969,15(1):42-56
Sans résumé
New trends in defining the functions of elementary education
Neue Tendenzen in der Beurteilung der Aufgaben des Elementarunterrichts相似文献