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101.
The paper adds to the existing literature on the determinants of government spending in Research and Development (R&D) by considering the role of strategic interactions among countries as one of the possible competing explanations, within a spatial econometric framework. We account for several factors affecting national levels of public R&D spending, including (i) the international context – i.e. Lisbon strategy; (ii) country characteristics – level of private R&D, GDP, trade openness and the National System of Innovation; (iii) countries’ similarities in relation to (a) trade and economic size and (b) sectoral specialization. The analysis is carried out on 14 European countries. First, we find that factors traditionally affecting the level of public R&D expenditure, such as the scale of the national economy, trade openness, sectoral specialization and private R&D, significantly influence the level of public R&D in European countries between 1994 and 2006. Interestingly, the introduction of the Lisbon strategy does not seem to have affected changes in the levels of public R&D spending. Second, by using different weight matrices, we confirm the existence of strategic interactions in relation to R&D spending among European countries with similar economic, international trade and sectoral structure characteristics, though not geographically close.  相似文献   
102.
算法谜题     
正出版社:人民邮电出版社出版时间:2014-03-01ISBN:9787115338440所属分类:图书计算机与互联网操作系统算法是计算机科学领域最重要的基石之一。算法谜题,就是能够直接或间接地采用算法来加以解决的谜题。求解算法谜题是培养和锻炼算法思维能力一种最有效和最有乐趣的途径。《算法谜题》是一本经典算法谜题的合集。书中包括了一些古已有之的谜题,数学和计算机科学有一部分知识就发源于此。《算法谜题》中还有一些较新的谜题,其中有一部分谜题  相似文献   
103.
The use of contrast media such as organic iodine molecules and gadolinium contrast agents is commonplace in diagnostic imaging. Although there is widespread perception that side effects and drug interactions may be the leading problems caused by these compounds, various degrees of interference with some laboratory tests have been clearly demonstrated. Overall, the described interference for iodinate contrast media include inappropriate gel barrier formation in blood tubes, the appearance of abnormal peaks in capillary zone electrophoresis of serum proteins, and a positive bias in assessment of cardiac troponin I with one immunoassay. The interference for gadolinium contrast agents include negative bias in calcium assessment with ortho-cresolphthalein colorimetric assays and occasional positive bias using some Arsenazo reagents, negative bias in measurement of angiotensin converting enzyme (ACE) and zinc (colorimetric assay), as well as positive bias in creatinine (Jaffe reaction), total iron binding capacity (TIBC, ferrozine method), magnesium (calmagite reagent) and selenium (mass spectrometry) measurement. Interference has also been reported in assessment of serum indices, pulse oximetry and methaemoglobin in samples of patients receiving Patent Blue V. Under several circumstances the interference was absent from manufacturer-supplied information and limited to certain type of reagents and/or analytes, so that local verification may be advisable to establish whether or not the test in use may be biased. Since the elimination half-life of these compounds is typically lower than 2 h, blood collection after this period may be a safer alternative in patients who have received contrast media for diagnostic purposes.  相似文献   
104.
This paper aims to determine the factors affecting the decisions of both male and female secondary school pupils whether or not to pursue undergraduate studies in Computing. It is based on research conducted in Greece, on a sample of 248 pupils, 135 of whom were female. All were aged 17 and about to decide on their future undergraduate studies. Questionnaires were used, addressing issues in the following four main categories: a) the reasons pupils chose/rejected Computing, b) how family and friends, the media and the school environment contribute to their decision, c) how pupils perceived their future after studying Computing and d) how pupils perceived the profile of a computer professional in terms of gender.
Maria KordakiEmail:
  相似文献   
105.
The present study reported on translating the Exercise Identity Scale (EIS: Anderson & Cychosz, 1994) into Greek and examining its psychometric properties and cross-cultural validity based on U.S. individuals' EIS responses. Using four samples comprising 33, 103, and 647 Greek individuals, including exercisers and nonexercisers, and a similar sample comprising 800 U.S. individuals, the concurrent validity, factor structure, internal reliability, test-retest reliability, external validity, gender invariance, and cross-cultural validity of the EIS responses were examined using confirmatory factor analytical procedures. The results supported the concurrent validity, an adequate unidimensional factor structure for the translated EIS and the internal reliability and test-retest reliability over a 6-week interval. Further, cross-gender configural, partial metric, partial strong factorial, and partial strict factorial invariance and cross-cultural configural and partial metric invariance supported the cross-cultural equivalence of the EIS versions. Moreover, the external validity of the translated EIS responses was also supported. Overall, the findings supported the validity of the exercise identity construct outside North American boundaries and the EIS items' equivalence, providing initial evidence for its cross-cultural applicability.  相似文献   
106.
107.
Abstract

In this study, we assessed the longitudinal effects of social-cognitive mechanisms on the self-reported use of doping substances and supplements among Italian high school students. In total, 1232 students completed questionnaires measuring various psychological factors hypothesized to influence students' intention to use substances. Three months later, 762 of the students completed the same questionnaires a second time and also reported their use of substances during the time between assessments. Overall, the percentages of students using doping substances (2.1%) or supplements (14.4%) were consistent with values reported in the literature. Analysis of the data showed that adolescents' intention to use doping substances increased with stronger attitudes about doping, stronger beliefs that significant others would approve of their use, a stronger conviction that doping use can be justified, and a lowered capacity to resist situational pressure or personal desires. In turn, stronger intentions and moral disengagement contributed to a greater use of doping substances during the previous 3 months. Doping use was also correlated significantly to supplementation. In conclusion, our results provide novel information about some of the psychological processes possibly regulating adolescents' use of doping substances and supplements. The results also highlight possible areas for future study and intervention, focusing on the prevention of adolescents' substance use.  相似文献   
108.
This paper explores the relationship between digital games and learning along the continuum from formal to informal learning. Games are an increasingly important component of our learning ecologies but their potential can prove difficult to fully harness due to the downsides of gaming in informal contexts and to the limitations games can present when adopted in formal learning contexts. The aim of this paper is to shed light on the strengths and weaknesses of games for learning, and to gather stakeholder recommendations for the main actors in the field. The adopted research approach is qualitative and participatory, involving players, teachers, parents, researchers and developers. Data from 25 interviews and 11 focus groups yielded insights into the educational, psychological and ethical aspects of play. Results suggest that gameplay influences individuals in a very personal manner, and that its effects cover a wide range of skills, extending to identity development. Hence, to harness this potential, all actors in the ecology need strong awareness of both the affordances and the risks of games, and deep respect for individuals’ LEs. The study has implications for a wide range of actors, including educators, players, researchers, parents, game developers and policymakers.  相似文献   
109.
110.
The aim of this investigation is to assess the effectiveness of a 6-week balance training (BT) protocol, integrated in regular training sessions, on postural sway of young female volleyball players (n = 26, age 13.0 +/- 0.2 years) divided into two groups (intervention and control; 13 per group). Trials were performed for bipedal and unipedal stance conditions before and after the BT protocol, using a pressure platform to collect center-of-pressure (COP) time series that were processed to calculate sway area, COP path length, and maximum displacement range in anteroposterior and mediolateral directions. The intervention group exhibited smaller sway areas in eyes closed conditions (intervention = 42.76 mm2, control = 67.60 mm2; p < 0.05) and Romberg quotients (intervention = 1.11 mm, control = 1.82 mm) in bipedal stance, while all the other parameters were unaffected. BT also reduced sway area (intervention = 122.70 mm2, control = 187.18 mm2) and anteroposterior COP displacements (intervention = 20.18 mm, control = 22.38 mm) of the non-dominant limb for single-leg stance. No significant change was found for the dominant limb. Although it is possible to hypothesize a beneficial effect of BT on young athletes, further investigations are required to clarify its actual effect on balance performance with respect to normal volleyball training.  相似文献   
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