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The end of the Cryogenian glaciations undoubtedly affected the chemistry of the Neoproterozoic oceans, with potential consequences for the evolution of life; the duration and extent of this influence are poorly constrained. Lithium (Li) isotopes in carbonates can be used to investigate past weathering events and riverine input into the oceans. Here, we report the Li isotope (δ7Li) composition of the Ediacaran cap dolostones (Marinoan) from the Nuccaleena Formation, South Australia and the Doushantuo Formation, South China to investigate changes in weathering during the aftermath of the Marinoan glaciation. The origin of dolomite formation is still hotly debated, and the inability to precipitate dolomite at ambient temperatures (the 'dolomite problem') has not yet been resolved. The dominant hypothesis for the presence of marine dolomite is that it is of secondary origin, owing to diagenetic replacement of calcium carbonate, but a second hypothesis is that it forms as a result of primary marine deposition; both are plausible hypotheses. Using carbon isotopes (δ13C) and ratios of manganese and strontium (Mn/Sr), we suggest that diagenesis may not have significantly altered the δ7Li composition of the primary dolomite, but this cannot be discounted without further diagenetic modelling. As a result, we cannot infer the δ7Li composition of the Ediacaran oceans, as further work must be done to address the impact of diagenesis on the δ7Li values. Nevertheless, this dataset contributes to a Li isotope chemostratigraphic record of the Proterozoic, which is a key element to understanding the emergence of complex life. [ABSTRACT FROM AUTHOR]

Background: There is a paucity of research regarding the attitudes of coaches towards training athletes with intellectual disabilities (ID). This is particularly evident for coaches working with athletes with ID that are competing in the innovative Special Olympics (SO) Unified Sports programme. Research on the inclusive impact of sport plays a significant role, not only in sports development but also in the training of sports professionals and coaches, as a sufficient amount of special coaching experience is required to achieve inclusion. For this reason, this study was conducted among professionals coaching tennis with athletes with ID. The purpose of this study was to analyse the attitudes of tennis coaches working with athletes with ID in the SO tennis programme. Methods: The study was conducted on a sample of internationally recognised elite tennis coaches (n = 78) working with tennis players with ID at two international tennis competitions. A questionnaire and a structured interview were conducted with the coaches to examine the sociometric characteristics of the coaches involved in the research. Findings were then compared with views on professional statements for similarities and differences in their attitudes towards their athletes and their work. Results: Results indicated that coaches felt the most important criteria for a coach working successfully with athletes with ID were (1) a wide range of knowledge, (2) professional expertise, (3) social sensitivity, (4) positive attitude and (5) motivation. Results supported the existing theoretical findings that besides professional expertise and experience, a basic knowledge about disability is needed among coaches working with athletes with ID. Conclusions: This research was unique in the international scene, in that, although the number of tennis coaches working within the movement of SO is relatively high, to this date, no scientific survey has been focused on them. [ABSTRACT FROM AUTHOR]

The Dunning-Kruger effect (DKE) in higher education evaluation is one of the current research areas of psychology, educational science, and management science (in our case). Its importance is that the less prepared one is, the less accurately one can judge what performance is expected of him. What is more, he will err more and will overestimate himself. The present study aims better to understand the phenomenon with new, small-sample empirical results. The study is part of a research series that has been ongoing at the University of Debrecen since 2015. It not only quantitatively expands the literature but also includes the course of Knowledge Management among those examined. During the research, students were asked both before the examination (N = 63) and after the examination (N = 76) to guess how many points they would achieve on a multiple-choice test. It supports the presence of DKE, both in the case of pre-examination and post-examination self-evaluations. Using four multivariate linear regression models, we examined whether the sign value or absolute value of the errors made during the guesses show a correlation - in addition to the available control variables - with the test score. Our results showed that the more accurate the pre-examination and post-examination estimations were, the higher the students' actual score was, while the less they tended to overestimate their preparation. This supports the presence of DKE, both in the case of pre-exam and post-exam self-evaluation. [ABSTRACT FROM AUTHOR]

Demographic history, current status, and efficiency of the mating strategy were analyzed using the pedigree of Pannon White (PW) rabbits born between 1992 and 2007. Potential accumulation of detrimental effects and loss of genetic diversity were also considered. Calculations and estimates were done most often for rabbits born in 2007, whereas other reference populations (REFPOPXXXX) were specified explicitly. The pedigree contained 4,749 individuals and 580 founders, and its completeness was 82.1% up to 10 and 94.5% up to 5 generations, respectively. Generation intervals through different pathways averaged 1.2 yr. When adjusted to the pedigree completeness, the amount of inbreeding ([F.sub.i]) of rabbits was comparable (5.54%) with that of other livestock populations, whereas the 10 (30) founders contributing the most to inbreeding explained a large part of the population inbreeding [i.e., 42.24% (73.18%)]. The ancestral inbreeding coefficient of REFPOP2004 (10.67%) was one-half that of REFPOP2007 (20.66%), showing its strong dependence on pedigree length. Family variance, inbreeding, and realized effective population size were 84.18 (REFPOP2006; this variable could not be calculated for the last year examined), 37.19, and 91.08, respectively. The effective numbers of ancestors, founders, and founder genomes were 48, 26, and 7.33, respectively. Although the circular mating scheme applied was generally effective, the large accumulated reduction in genetic variability indicates the need to revise and improve the current breeding strategy. Key words: genetic diversity, inbreeding coefficient, Pannon White rabbit, pedigree analysis doi: 10.2527/jas.2009-2273