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1.
Innovative public procurement is increasingly considered as a form of public support for private innovation activities by both innovation scholars and policymakers. Economic historians have suggested an even more fundamental role of public procurement in setting the pace of technological change, reporting how defense-related procurement has had a major impact on the emergence and diffusion of many general purpose technologies developed in the United States in the 20th century. In this paper, I suggest that procurement might represent one of the most important elements in creating the right soil to ‘cultivate’ a technology that may have the potential to reach high levels of pervasiveness. To test this hypothesis, I make use of patent data and patent citations. I design a quasi-experiment to compare the changes in the level of generality level over time, between a group of treated and a group of control patents. A patent is assigned to the treatment group if it receives a citation from a patent related to public procurement. Results suggest a positive and significant impact of innovative public procurement on the generality of a patent.  相似文献   
2.
Bioelectrical impedance vector-analysis (BIVA) describes cell-mass, cell function and hydration status of an individual or a group. The goal of the present investigation was to provide bioelectrical impedance data for 525 male road cyclists (155 professionals, 79 elite, 59 elite-youth, and 232 amateurs) at the time of their optimal performance level. Data were plotted on the resistance-reactance (R-Xc) graph to characterize cyclists group vectors using BIVA. Compared to the general male population, the mean vector position of the road cyclists indicates a higher body cell mass (BCM) and phase angle (p<0.001). The vector position of the high-performance, compared to the amateur cyclists showed similar patterns with higher BCM and phase angles and higher reactance values for the high-performance athletes (p<0.001). The bio-impedance data were used to calculate the 50%, 75%, and 95% tolerance ellipses of each group of cyclists. The characteristic vector positions of the road cyclists indicate normal hydration and greater muscle mass and function of the high-performance cyclists compared to amateur cyclists and the normal population. The cyclists specific tolerance ellipses, particularly the high-performance cyclists might be used for classifying a cyclist according to the individual vector position and to define target vector regions for lower level cyclists.  相似文献   
3.
Abstract

This study provides evidence on the impact of including warm messages in elaborated feedback. These messages are aimed at the motivational process that can be mobilised by feedback and that which can condition its reception and the way students face the task (post-feedback behaviour). In a task where secondary school students had to learn a new strategy for improving their reading skills in a computer-based environment, we compared the use of elaborated feedback with the use of elaborated feedback enhanced with motivational messages (warm elaborated feedback) and a control condition (without feedback). The results showed that students receiving warm elaborated feedback revisited the text more often than those receiving only the elaborated feedback, and that both groups revisited the text more than the control group. This finding suggests that controlling the motivational aspects in feedback messages may increase the effectiveness of elaborated feedback.  相似文献   
4.
This paper provides an overview of the knowledge management systems (KMSs) adopted by small and medium enterprises (SMEs). KMSs are divided into two categories: knowledge management tools (KM-Tools) and knowledge management practices (KM-Practices). On the basis of the analysis of the literature, two research questions (RQs) were identified and addressed through semi-structured interviews carried out in a sample of 35 SMEs operating in high-tech industries. The first RQ concerns the degree of adoption of KMSs by SMEs. The second RQ regards the relationship between KM-Tools and KM-Practices. As far as the degree of adoption of KMSs, the paper highlights that SMEs are not a homogeneous world but there are a variety of approaches and behaviours. As far as the relationship between the degree of adoption of KM-Tools and KM-Practices, the paper identifies three groups of SMEs that seem to point out the stages of the process of adoption of KMSs: Introduction, SMEs that deal with the process of knowledge management exploiting practices and tools that are already known; Growth, SMEs that adopt specialist practices of knowledge management acquiring new organisational and managerial competence in the field of knowledge management; Maturity, SMEs that invest in new technology and that acquire new technological competence in the field of knowledge management. This categorisation paves the way for further theoretical and practical implications for both managers and policy makers.  相似文献   
5.
One set of samples from wall paintings of the Xth Regio of Italy containing green colours was analysed exploiting different spectroscopic techniques, aiming to identify the pigments used. The possibility to distinguish between glauconite and celadonite, the most common green pigments used in such paintings, was of particular interest. Samples of celadonite from Monte Baldo and glauconite from Belgium were considered as standard materials for comparison. The results obtained using FTIR, EDS, AAS, Colorimetry, Raman and EPR spectroscopies were compared for the identification of the green pigments.  相似文献   
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7.
The notion of improvisation has recently emerged in managerial studies as a viable answer to flexibly dealing with unexpected occurrences. Nonetheless, research on improvisation has essentially approached the issue through a metaphorical framework, and has regularly relied on conceptual frameworks residing either at the individual or the team-level. We investigate how team-level processes affect individual improvisation in complex project domains. Using data from 138 team leaders and members belonging to 38 information systems development teams, we test cross-level hypotheses through hierarchical linear modeling. Team behavioral integration and team cohesion positively affect individual improvisation. Moreover, cohesion positively moderates the influence of team behavioral integration on individual improvisation. In concluding this paper we offer theoretical and practical implications.  相似文献   
8.
In soccer, the players perform intermittent work. Despite the players performing low-intensity activities for more than 70% of the game, heart rate and body temperature measurements suggest that the average oxygen uptake for elite soccer players is around 70% of maximum (VO(2max). This may be partly explained by the 150 - 250 brief intense actions a top-class player performs during a game, which also indicates that the rates of creatine phosphate (CP) utilization and glycolysis are frequently high during a game. Muscle glycogen is probably the most important substrate for energy production, and fatigue towards the end of a game may be related to depletion of glycogen in some muscle fibres. Blood free-fatty acids (FFAs) increase progressively during a game, partly compensating for the progressive lowering of muscle glycogen. Fatigue also occurs temporarily during matches, but it is still unclear what causes the reduced ability to perform maximally. There are major individual differences in the physical demands of players during a game related to physical capacity and tactical role in the team. These differences should be taken into account when planning the training and nutritional strategies of top-class players, who require a significant energy intake during a week.  相似文献   
9.
A metric analysis of blogs on library and information science (LIS) between November 2006 and June 2009 indexed on the Libworm search engine characterizes the community's behavior quantitatively. An analysis of 1108 personal and corporate blogs with a total of 275,103 posts is used to calculate survival rate, production (number of posts published), and visibility via such indicators as links received, Technorati authority, and Google's PagePank. Over the study period, there was a 52% decrease in the number of active blogs. Despite the drop in production over this period, the average number of posts per blog remained constant (14 per month). The most representative blogs in the discipline are identified. The emergence of such platforms as Facebook and Twitter seems to have meant that both personal and corporate blogs have lost some of their prominence.  相似文献   
10.
Several composite indexes grouping several variables into a single figure have been proposed for measuring the digital divide. In this article, the authors analyze shortcomings of extant indexes. Using multivariate analysis tools, they show that in the definition of composite indexes it is possible to individuate a limited set of more influencing and significant variables. This finding suggests the possibility of replacing some redundant variables with other dimensions that include other aspects of the digital divide that are not considered in extant measures.  相似文献   
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