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61.
62.
The ability to predict the long-term impact of a scientific article soon after its publication is of great value towards accurate assessment of research performance. In this work we test the hypothesis that good predictions of long-term citation counts can be obtained through a combination of a publication's early citations and the impact factor of the hosting journal. The test is performed on a corpus of 123,128 WoS publications authored by Italian scientists, using linear regression models. The average accuracy of the prediction is good for citation time windows above two years, decreases for lowly-cited publications, and varies across disciplines. As expected, the role of the impact factor in the combination becomes negligible after only two years from publication.  相似文献   
63.
Scholars and policy makers recognize that collaboration between industry and the public research institutions is a necessity for innovation and national economic development. This work presents an econometric model which expresses the university capability for collaboration with industry as a function of size, location and research quality. The field of observation is made of the census of 2001–2003 scientific articles in the hard sciences, co-authored by universities and private enterprises located in Italy. The analysis shows that research quality of universities has an impact higher than geographic distance on the capability for collaborating with industry. The model proposed and the measures that descend from it are suited for use at various levels of administration, to assist in realizing the “third role” of universities: the contribution to socio-economic development through public to private technology transfer.  相似文献   
64.
The aim of the paper is twofold: to report on theapplication of a contingent valuation survey todetermine the value to the Naples population ofmaintaining ``Napoli Musei Aperti', a cultural publicgood provided by the city of Naples, and to exploresome alternative schemes of cultural policy. The paperis divided in two parts. The first presents someresults of the contingent valuation study. The seconddiscusses the use of the contingent valuation as apolicy instrument in the public cultural sector.  相似文献   
65.

Introduction

The study of cardiac response to strenuous and continuous exercise is crucial to understanding the physiology of endurance. N-terminal proB-type natriuretic peptide (NT-proBNP) is a potential marker for monitoring myocardial wall stress, and troponins (TnT and TnI) are widely used in the diagnosis of cardiac ischemia and infarction. Strenuous exercise may generate transitory ischemia, myocardial stress, and diastolic left ventricular dysfunction, inducing the increased production of both these biomarkers. We measured changes in NT-proBNP and TnT in elite cyclists during a 3-week stage race, a model of strenuous exercise.

Materials and methods:

The study population was 9 professional cyclists participating in the 2011 Giro d’Italia. Pre-analytical and analytical phases scrupulously followed official recommendations. Anthropometric data, net energy expenditure and cardiac indexes (rate, diastolic and systolic blood pressure) were recorded. Blood samples were drawn pre-race (day −1) and at days 12 and 22; NT-proBNP and highly sensitive-troponin (Hs-TnT) concentrations were assayed and corrected for plasma volume changes.

Results:

Body-mass index decreased and energy expenditure increased by 52% during the race. NT-proBNP concentrations increased [day −1: 23.52 ng/L (9.67–34.33); day 12: 63.46 ng/L (22.15–93.31); P = 0.039; day 22: 89.26 ng/L (34.66–129.78) vs. day −1; P < 0.001] and correlated with heart rate (r = −0.51; P = 0.006), systolic pressure (r = 0.39; P = 0.046) and energy expenditure (r = 0.70; P < 0.001). TnT concentrations did not vary, but a widened TnT amplitude distribution was observed.

Conclusions:

Increases in NT-proBNP correlated with higher energy expenditure over a 3-week cycling stage race, possibly indicating myocardial stress.  相似文献   
66.
The incidence of extramural collaboration in academic research activities is increasing as a result of various factors. These factors include policy measures aimed at fostering partnership and networking among the various components of the research system, policies which are in turn justified by the idea that knowledge sharing could increase the effectiveness of the system. Over the last two decades, the scientific community has also stepped up activities to assess the actual impact of collaboration intensity on the performance of research systems. This study draws on a number of empirical analyses, with the intention of measuring the effects of extramural collaboration on research performance and, indirectly, verifying the legitimacy of policies that support this type of collaboration. The analysis focuses on the Italian academic research system. The aim of the work is to assess the level of correlation, at institutional level, between scientific productivity and collaboration intensity as a whole, both internationally and with private organizations. This will be carried out using a bibliometric type of approach, which equates collaboration with the co-authorship of scientific publications.
Giovanni AbramoEmail:
  相似文献   
67.
We report characteristics of in-text citations in over five million full text articles from two large databases – the PubMed Central Open Access subset and Elsevier journals – as functions of time, textual progression, and scientific field. The purpose of this study is to understand the characteristics of in-text citations in a detailed way prior to pursuing other studies focused on answering more substantive research questions. As such, we have analyzed in-text citations in several ways and report many findings here. Perhaps most significantly, we find that there are large field-level differences that are reflected in position within the text, citation interval (or reference age), and citation counts of references. In general, the fields of Biomedical and Health Sciences, Life and Earth Sciences, and Physical Sciences and Engineering have similar reference distributions, although they vary in their specifics. The two remaining fields, Mathematics and Computer Science and Social Science and Humanities, have different reference distributions from the other three fields and between themselves. We also show that in all fields the numbers of sentences, references, and in-text mentions per article have increased over time, and that there are field-level and temporal differences in the numbers of in-text mentions per reference. A final finding is that references mentioned only once tend to be much more highly cited than those mentioned multiple times.  相似文献   
68.
In Italy, data and information on prevalence and characteristics of elder abuse are very limited, and a specific legal and policy framework is lacking. Some articles of the Penal Code refer to the larger context of violence against disadvantaged groups, and some general support services not specifically dedicated to this issue are managed by local municipalities. In this context, empirical research is useful for disseminating information and implementation of good practices. Such research indicates future directions for the education of the public and training of professionals on the prevention, detection, and treatment of abusive practices.  相似文献   
69.
The efficiency of a long-span structure relies on how material is locally distributed within a fixed structural shape. In this paper a design procedure for thin plates made of three layers of a depleted material subject to a distributed vertical load is proposed. The investigation is driven by the idea of the optimal material organization and has the objective of maximizing the overall stiffness/weight ratio of the structure. Two microstructural architectures of the media are considered: a porous solid structure and a truss arrangement. For each type of microstructure the flexural stiffness has been correlated to the level of depletion by the use of a power law function by setting very few parameters. Finally, invoking the principles of structural homogenization theory, the global flexural response of the plate has also been calculated. The validity of the method is demonstrated by comparing the analytical results with those obtained by a numerical finite element simulation of the structure based on a detailed model of the media.  相似文献   
70.
This longitudinal study examined change in adolescents' daily range of emotional states between early and late adolescence. A sample of 220 youth provided reports on their daily emotions at random times during two 1-week periods. At Time 1 they were in the fifth through eighth grades; 4 years later, at Time 2, they were in the ninth through twelfth grades. Results showed that average emotional states became less positive across early adolescence, but that this downward change in average emotions ceased in grade 10. The results also showed greatest relative instability between youth in the early adolescent years--correlations over time were lower--with stability increasing in late adolescence. Lastly, the study found that adolescents' average emotions had relatively stable relations to life stress and psychological adjustment between early and late adolescence. As a whole, the findings suggest that late adolescence is associated with a slowing of the emotional changes of early adolescence.  相似文献   
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