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201.
This study examines the effect of R&D tax credits on innovation activities of Canadian manufacturing firms. Over the 1997-1999 period the Federal and Provincial R&D tax credit programs were used by more than one third of all manufacturing firms and by close to two thirds of firms in high-technology sectors. We investigate the average effect of R&D tax credits on a series of innovation indicators such as: number of new products, sales with new products, originality of innovation, etc. using a non-parametric matching approach. Compared to a hypothetical situation in the absence of R&D tax credits, recipients of tax credits show significantly better scores on most but not all performance indicators. We therefore conclude that tax credits lead to additional innovation output.  相似文献   
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This systematic review presents the latest trends in salivary research and its applications in health and disease. Among the large number of analytes present in saliva, many are affected by diverse physiological and pathological conditions. Further, the non-invasive, easy and cost-effective collection methods prompt an interest in evaluating its diagnostic or prognostic utility. Accumulating data over the past two decades indicates towards the possible utility of saliva to monitor overall health, diagnose and treat various oral or systemic disorders and drug monitoring. Advances in saliva based systems biology has also contributed towards identification of several biomarkers, development of diverse salivary diagnostic kits and other sensitive analytical techniques. However, its utilization should be carefully evaluated in relation to standardization of pre-analytical and analytical variables, such as collection and storage methods, analyte circadian variation, sample recovery, prevention of sample contamination and analytical procedures. In spite of all these challenges, there is an escalating evolution of knowledge with the use of this biological matrix.Key words: saliva, non-invasive, biological markers, drug monitoring, oral health  相似文献   
208.
Purpose: Educational methods to diagnose and improve the level of environmental conception are required. The present work reports a methodology based on studies about the environmental perception of a university public, divided into general students and those related to the forest sciences, who are involved with disciplines and researches related to e.g. environmental management.

Design/Methodology/Approach: The environmental perception obtained from the graphical representation of environment and the most relevant actions indicated by the students to achieve the environmental conservation, divided in four levels of complexity, were correlated using principal component analysis.

Findings: The students from both groups having the highest scores in environmental perception prioritize actions related to the comprehension and responsibility levels, while the ideal scenario would be to indicate actions related to competence and citizenship. Thus, the complex concept about environment of the students is still incipient and, therefore, educational strategies can be traced based on the profiles obtained.

Practical Implications: The method for environmental perception can be designed for different populations and a scheme relating environmental perception with four levels of actions on behalf of the environmental conservation is proposed to diagnose environmental conceptions, as well as to guide educational strategies about socio-ecological system.

Originality/Value: A semi-quantitative method was developed to estimate, clearly and directly, the level of complexity about the environmental knowledge of university students and, consequently, to predict the actions on behalf of the environmental conservation that they would probably perform.  相似文献   

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The term intensive scaffolding refers to any set of conceptual scaffolding strategies that always allow the user to find the solution to a problem. Despite the many benefits of scaffolding, some negative effects have also been reported. These are mainly related to the possibility that a student solves the problems without actually engaging in their content. In this paper, we have used an intelligent tutoring system (ITS) to analyze the effect that intensive scaffolding has on the learning of algebraic word problem solving (AWPS). Two different versions of the ITS, which differ in the amount of scaffolding that they provide, have been created. These two versions were used by two groups of students in Secondary Education, in a quasi‐experimental study. The comparison of pre‐ and posttest scores shows a significant increase of the competence in AWPS in the group that used the ITS with intensive scaffolding.  相似文献   
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ABSTRACT

In order to investigate the effect of playing styles on the match performance of football teams, data were analysed on 18 technical performance-related variables and 8 physical performance-related variables from 59 matches in the 2018 FIFA World Cup. A k-means cluster analysis was conducted to classify all match observations into two clusters of tactical approach in order to identify the playing styles of teams (characterised as direct-play, possession-play and mixed-play). Separate Poisson regression models were run in the generalised mixed linear modelling to examine the differences in technical and physical performance between teams classified as using different playing styles when facing different opponents. Results showed that possession-play characterised teams achieved higher values in all the variables related to goal scoring, attacking and passing (ES: 0.32 ~ 1.27) and covered more distance in sprints and high-intensity running (ES: 0.33 ~ 0.47) than direct-play characterised teams. Both possession- and direct-play characterised teams achieved higher values in passing, pass accuracy and delivery into the attacking third playing against direct-play characterised teams than playing against possession-play characterised sides (ES: 0.22 ~ 0.98). These findings may provide insights into the establishment of performance profiles of teams with different tactical styles and the development of specific training drills to optimise playing style.  相似文献   
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