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61.
62.
In December 2000, five Polish state institutions of higher education in economics established the Foundation for the Promotion and Accreditation of Economics Programmes. Its mission, as stated in its charter, is to improve the quality of economics and management education by disseminating and supporting its best models. This mission takes on particular importance on the eve of the inclusion of Polish higher education institutions into the European Higher Education Area. This article serves as a case study based on the experience of the Poznan´ University of Economics and what it gained from its accreditation in early 2003.  相似文献   
63.
Dual-task effect on postural control in high-level competitive dancers   总被引:1,自引:0,他引:1  
We investigated balance in 33 competitive dancers (17 females, 16 males) and 22 controls (17 females, 5 males) (age 16-27 years) on a force plate in two conditions: single task (quiet stance) and dual task (with a concurrent mental task). Balance was evaluated using centre-of-pressure shift (sway) variability, mean speed, frequency, and sample entropy. The effect of the dual task in the medio-lateral plane was comparable in both groups, decreasing sway variability (P < 0.05) and increasing mean speed (P < 0.001), frequency, and sample entropy (P < 0.001), showing that the participants effectively increased the level of automaticity. In the antero-posterior plane, the dual task also increased sway frequency and sample entropy (P < 0.01) in dancers without affecting their standing performance. In contrast, postural control in non-dancers was vulnerable to reduced cognitive investment, which adversely interfered with baseline performance. There were very high correlations between sway sample entropy and frequency in each group, plane, and task (r = 0.92-0.98, P < 0.001), indicating that both parameters may measure the same characteristic of postural control and that higher sway frequency may play an important role in protecting stability in dual tasking. The postural control of dancers and non-dancers appears to be similar, although dancing seems to facilitate the increased level of automatic control in the antero-posterior plane.  相似文献   
64.
In order to determine the usefulness of neural models in optimisation of recruitment processes, statistical analyses were carried out on measured results of javelin throwers using a full take off. A group of 140 Polish junior javelin throwers took part in the research. In order to choose the optimum combination of model parameters the Hellwig method was used. Linear and multilayer perceptron neural models were constructed and used to calculate combinations of variables. Statistical analysis of the results showed that the linear model was not able to describe precisely the relationship between the dependent variable and independent variables for the investigated group of young javelin throwers. For the investigated group, the perceptron network with a 4-3-2-1 structure gave the best predictive relationship for sports results of the javelin throwers.  相似文献   
65.

Objective

Decompensated chronic hyperglycemia often leads to late microvascular complications such as retinopathy, diabetic foot syndrome, and diabetic kidney disease. The aim of this study was to determine the concentration of vascular endothelial growth factor A (VEGF-A) and its receptors in patients with well-controlled diabetes.

Methods

The study was conducted on 31 patients with well-controlled type 2 diabetes without micro-or macroangiopathy. Thirty healthy volunteers were enrolled in a control group. Serum concentrations of VEGF-A, VEGF receptors 1 and 2 (VEGFR1 and VEGFR2), fasting glucose, and lipid profiles were measured, and the plasma concentration of glycated hemoglobin (HbA1c) was determined.

Results

No significant differences were observed between the concentration of VEGF-A, VEGFR1 or VEGFR2 in the subject group and that in the control group. Positive correlations were noted between the levels of VEGF-A, VEGFR2, and triglyceride, and there was a negative correlation between the levels of VEGFR2 and high-density lipoprotein (HDL)-cholesterol in the study group.

Conclusions

The concentrations of VEGF-A and its receptors 1 and 2 in patients with well-controlled diabetes are comparable to those of healthy individuals, which may indicate that appropriate control of glucose levels delays the occurrence of vascular complications. A negative correlation between VEGFR2 and HDL-cholesterol levels, and positive correlations between VEGF-A, VEGFR2, and triglyceride levels, suggest that lipid abnormalities occurring in diabetes may be involved in the modulation of angiogenesis.  相似文献   
66.
Cross-border migration has increased rapidly in recent decades. In response, most democracies have extended voting rights to their citizens abroad. Nevertheless, expatriate voter turnout tends to be low. This article investigates a frequently proposed remedy—internet voting—based on a case study of extended internet voting trials in eight Swiss cantons. For causal identification, I exploit an unexpected federal intervention that led to a temporary suspension of internet voting in four of the eight cantons, during which expatriates could vote only by mail. Using difference-in-differences estimation, I find that the temporary suspension of internet voting decreased turnout among registered expatriate voters by 4.1 to 6.4 percentage points. Placebo tests suggest that pre- and post-suspension trends in expatriate voter turnout were close to identical in treated and control cases. Overall, the results of this study suggest that internet voting represents an effective method to increase electoral participation among citizens abroad. Still, expatriate voter turnout remained well-below domestic turnout even with internet voting available, suggesting that high voting costs are not the only reason why citizens abroad tend to vote at lower rates.  相似文献   
67.
68.
The emerging research area of opinion mining deals with computational methods in order to find, extract and systematically analyze people’s opinions, attitudes and emotions towards certain topics. While providing interesting market research information, the user generated content existing on the Web 2.0 presents numerous challenges regarding systematic analysis, the differences and unique characteristics of the various social media channels being one of them. This article reports on the determination of such particularities, and deduces their impact on text preprocessing and opinion mining algorithms. The effectiveness of different algorithms is evaluated in order to determine their applicability to the various social media channels. Our research shows that text preprocessing algorithms are mandatory for mining opinions on the Web 2.0 and that part of these algorithms are sensitive to errors and mistakes contained in the user generated content.  相似文献   
69.
This article reports on a study using data from nation-wide standardised examinations in Poland. We analysed the extent to which grade 9 student achievements have depended on the stability of their peer group over the course of middle school. We controlled for the fixed effects of schools attended by the students, as well as for individual achievements prior to middle school enrolment. To mitigate the risk for endogeneity, analysis was informed by a consideration of the fact that middle schools operate in different institutional relations with nearby primary schools. This also allowed us to distinguish between the effect related to peer group stability and the one connected to the stability of the learning environment in general. The results of our analysis show that instability significantly reduces students' expected performance in mathematics and science. The impact of peer group stability on test achievements varies strongly across the student ability distribution. Very low-performing students and top performers were most affected. The average students were largely unaffected. One category of students that seems to benefit from the change when moving to middle school are students from very competitive primary schools who have average skills.  相似文献   
70.
Although there is near consensus on the need for privacy, the reality is that people's attitude toward their personal information privacy is complex. For instance, even when people claim that they value their information privacy, they often trade their personal information for tangible or intangible benefits. In this article, the research on different ways in which people respond to risks to privacy is examined. They include information seeking to reduce uncertainty, the withholding of information, and the provision of fabricated information. The impact of trust and inducements on Internet users’ willingness to share personal information is also examined. Thereafter, important postulates from theories in communication, social psychology, and sociology are synthesized into a comprehensive theoretical framework for personal information-related behaviors in the online environment.  相似文献   
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