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61.
Since most activists participating in the recent uprisings in Arab countries have been using social media to an unprecedented extent, public analyst and researchers have rushed to reflect on and explain the phenomena, often attributing a ‘change agency’ to social media as such. This argumentative research collects evidence from literature, recent surveys and focus groups in order to contextualize our understanding of the role of social media and its usage in reshaping the Arab government–citizen relationship: Are the traits of social media significant enough to single them out and discuss their specific impact on the government–citizen relationship? Are we well advised to attribute an ‘agency’ of social media in shaping politics and inducing political change? And in view of the actual use of social media: What are the options of containing emerging ‘destructive’ phenomena and ‘improving’ the government–citizen relationship? Answers are outlined to support contextualized design of social media technology and regulation: (1) Arab citizens basically support democratic concepts; however (2) social media as such do not act and therefore do not ‘create’ e.g. democracy; rather (3) social media enable a new political sphere for Arab citizens, nevertheless challenged by realpolitik; and (4) social media need care taking in terms of shaping political communication and shaping the media itself in order to serve well as mediator among citizens and between citizens and government. 相似文献
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Diana Lebherz-Eichinger Remy Schwarzer Michael C. Motal Daniel A. Klaus Andreas Mangold Hendrik J. Ankersmit Gabriela A. Berlakovich Claus G. Krenn Georg A. Roth 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(2):252-261
Introduction
Sparse data are available about the effect of therapy methods on antibody levels in patients with liver failure. The aim of this study was to determine serum immunoglobulin concentrations in patients with chronic hepatic failure (CHF), acute- (ALF), or acute-on-chronic liver failure (ACLF) and to evaluate the impact of MARS treatment or liver transplantation (LT) on antibody levels.Materials and methods
We followed ten patients with ALF, twelve with ACLF and 18 with CHF. Eight patients with ALF and seven with ACLF underwent MARS therapy, whereas the rest received LT. 13 healthy volunteers served as controls. Serum antibody concentrations were measured using ELISA-technique.Results
Median serum levels of IgA, IgG and IgM were significantly increased in patients with CHF compared to ALF or controls (P < 0.02, P < 0.01, and P < 0.01). IgM and IgG concentrations were also significantly elevated in patients with CHF compared to ACLF (IgM, 3.7 vs. 1 g/L, P < 0.001; IgG, 8.7 vs. 3.1 g/L, P = 0.004). Immediately after LT a significant decrease of IgA (6.9 vs. 3.1 g/L, P = 0.004), IgG (8.7 vs. 5.1 g/L, P = 0.02) and IgM (3.7 vs. 1.8 g/L, P = 0.001) was detected in patients with CHF and antibody levels further decreased the days after LT reaching levels comparable to healthy individuals. MARS treatment had no apparent effect on the immunoglobulin profile in patients with ALF or ACLF.Conclusion
We provide evidence that LT reverses hypergammaglobulinemia in patients suffering from CHF within one day, which could be explained to a reconstituted hepatic antibody clearance, whereas MARS treatment has no immediate effect on immunoglobulin levels.Key words: antibodies, immunoglobulins, liver failure, liver transplantation, artificial liver support system, molecular adsorbent recirculating system 相似文献64.
While administrations, and especially e-government “followers,” have been recommended adopting service-oriented architecture (SOA) for the purpose of implementing G2G interoperability, the challenges of reaching this objective remain significant. General guidelines for service development and SOA governance are published, but in view of many self-contained units and IT departments on all administrative levels as well as widespread outsourcing of software development there is a lack of sharing “best practices” how to implement SOA step by step in the area of e-government. In particular, it is unknown to what extent administrations are able to follow existing service development approaches, and there is no research addressing the contribution of service development methods towards governance, i.e. developing and managing government interoperability. In this research the case of Egypt, where SOA was chosen as the main interoperability approach, has been explored in terms of to what extent the current approach to service development supports the interoperability governance, and what kind of changes in the development methods and their application would yield improvements in interoperability governance. The case analysis on practical and strategic level leads to proposing success factors related to linking the methodology of developing G2G services to the overall effort of interoperability governance. These factors, divided into interoperability problem perception, method scoping and deliverables, measurement of goal achievement, and methodological commitment, can be used as hypotheses in future research and as guidelines for improving the interoperability governance in administrative practice. 相似文献
65.
This article analyzes the interdependency between the market for music recordings on the one side and the market for concert tickets on the other side, assuming that there are positive indirect network effects both from the record market to ticket sales for live performances and vice versa. In a model with two interrelated Hotelling lines, prices in both markets are corrected downward when compared to the standard Hotelling model. In the integrated business model, file sharing has an ambiguous effect on firms' profitability. As file sharing can indirectly increase demand for live performances, overall profits can either increase or decrease, depending on the strength of indirect network effects. Finally, file sharing may induce firms to switch from the traditional business model with two separate firms to an integrated business model where one agency markets both records and concerts (so-called 360° deals). 相似文献
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This study concentrates in part on the market of fine arts. First, fine arts will be defined from a marketing point of view and peculiarities in the market of fine arts will be analysed empirically and theoretically. Certain aspects of marketing theory are discussed regarding their significance for the fine arts. Results of an empirical study of galleries and artists will be presented. It will be shown, whether and how artists are involved in marketing, how successful they are and what prerequisites to marketing the artists have. 相似文献
68.
Text anxiety research in West German schools is explored and measures currently used are described. Test anxiety is examined in relation to academic achievement research and theory. Distinctions between state and trait anxiety and between worry and emotionality are discussed. Test anxiety is investigated both in the traditional tripartite school system as well as in the non-traditional unitary comprehensive school. Results of several longitudinal studies point to the findings that there are socialization effects as explained by reference group theory and that these effects also are specific to the particular learning environment which the students experience in each school system. Future directions of test anxiety research in West German schools are explored. 相似文献
69.
Christian Saal Jochen Zinner Harald Fiedler Ralf Lanwehr Jürgen Krug 《Sportwissenschaft》2018,48(3):334-340
The aim of this study was to investigate the reliability and validity of a soccer short passing test using the Footbonaut training system. Forty-eight young skilled soccer players and 31 lesser-skilled soccer players completed a test and a retest, each involving four sessions a day of a Footbonaut short passing test (FSPT). We found significant differences in mean execution times for skilled (mean [M]?=?2487, standard deviation [SD] ?=?155) and lesser-skilled players (M?=?2682, SD?=?176) but no significant difference in accuracy (M?=?74.13, SD?=?7.65; M?=?72.19, SD?=?8.13) between groups. The results from linear mixed-effects models show that there were no significant effects of repeated measurements on execution time. In contrast, we found an estimated increase of 0.86% in accuracy per session for both groups. In conclusion, the FSPT offers a reliable and valid method to differentiate young soccer players at different competitive levels, using execution time. 相似文献
70.
Ernst-Joachim Hossner Urs Schnyder Jürg Schmid Ralf Kredel 《Journal of sports sciences》2019,37(13):1481-1489
The present study aims to reveal the effects of positioning on decision-making performance in top-level refereeing in association football. To this end, for all 64 matches of the FIFA World Cup 2014, potential foul-play situations were videometrically analysed in terms of the referee’s position relative to the infringement. Contrary to earlier studies, viewing angles were analysed in addition to viewing distances and error rates were considered for not only falsely whistled but also falsely non-whistled events. Moreover, direct logistic regression analysis was applied to detect position-dependent differences. For the total of 1,527 potential foul play situations, an overall low error rate of 6.9% was found. The similar numbers of total whistle (n = 52) and non-whistle errors (n = 54) reflect referees’ ability to balance both types of errors. Regarding the overall viewing-distance effect, referees were 2.58 times (95% CI 1.47–4.54) more likely to commit a whistle error at 10–15 m and 5.51 times (95% CI 1.35–22.47) more likely to commit a non-whistle error at 0–5 m, corresponding to the position ranges occurring with the highest (10–15 m: 30.3%) and lowest (0–5 m: 5.8%) frequencies. In contrast, no significant effects of viewing-angle on decision-making accuracy could be revealed. 相似文献