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The paper questions some of the premises in studying academic spin-offs in developed countries, claiming that when taken as
characteristics of ‘academic spin-offs per se,’ they are of little help in understanding the phenomenon in the Eastern European
countries during the transitional and post-transitional periods after 1989. It argues for the necessity of adopting a path-dependent
approach, which takes into consideration the institutional and organisational specificities of local economies and research
systems and their evolution, which strongly influence the patterns of spin-off activity. The paper provides new findings and
original arguments in support of Balazs’ seminal theses (Balazs 1995, 1996) about the emergence of academic spin-offs during the early transition. It reveals key economic and policy mechanisms bearing
on academic entrepreneurship in Eastern Europe, such as the tensions between economic and political nomenclatures of former
Communist Parties, where the dismantling or preservation of the power of political nomenclature resulted in different patterns
of development—rapid reforms in the ‘first wave’ of EU accession countries or the establishment of rent-seeking and assets-stripping
economies in countries like Bulgaria and Romania, making the transition period especially difficult. In the latter, a specific
economic environment emerged, unknown in Western Europe and in the ‘champions’ of transition—such as suppression of the authentic
entrepreneurship in a number of economic sectors, disintegration of corporate structures, etc. Thus, the paper reveals the
common ground behind the two conflicting tendencies in post-socialist academic spin-offs, partially outlined in other research
(Simeonova 1995; Pavlova 2000): as an authentic form of academic entrepreneurship grasping the opportunities opened up by the economic crisis and compensating
failures in science and technology policy on the one hand, and as specific rent-seeking strategy draining valuable public
assets on the other (the latter, in turn, boosting the negative attitudes in local scientific communities). The paper provides
new findings about the evolution of the academic spin-offs in Bulgaria along the two polar trends and their positive and negative
repercussions on parent research institutions. The results were achieved in the PROKNOW Project, EC 6th Framework Program. 相似文献
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Vanja Radi&#x;i&#x; Biljak Valentina Vidranski Lana Rui&#x; Ana-Maria Simundic Tihomir Vidranski 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(1)
IntroductionIntensive physical activity causes functional and metabolic changes in the athlete’s organism. The study aimed to verify the common national available reference intervals (RIs) for common inflammatory and screening coagulation tests in a population of healthy young female athletes.Materials and methodsOne hundred and twenty-one female athletes (age range: 16–34), from various sports disciplines (water polo, handball, volleyball, football, basketball), were included in the study. All participants completed the international physical activity short-form questionnaire. Blood samples were collected between 8–10 am, after an overnight fast, before any physical activity. Reference intervals were determined according to Clinical & Laboratory Standards Institute EP28-A3C Guidelines.ResultsCalculated RIs for white blood cell count (WBC), prothrombin time (PT), and activated partial thromboplastin time (APTT) ratio were in accordance with the common national RIs. Calculated RI for C-reactive protein (CRP) was lower (< 2.9 mg/L) than the proposed cut-off for a healthy population (< 5.0 mg/L). Reference interval for fibrinogen was higher (1.9–4.4 g/L), than the available RIs (1.8–3.5 g/L). D-dimer cut-off value was set at 852 µg/L fibrinogen equivalent units (FEU), higher than the proposed 500 µg/L FEU for venous thromboembolism (VTE) exclusion.ConclusionsThe applicability of the available RIs for WBC count, PT, and APTT-ratio was confirmed. However, RIs for CRP and fibrinogen differed significantly than the available common national RIs for the healthy non-athletes’ population. A higher cut-off for D-dimers should be extensively verified before implementation for VTE diagnosis exclusion in a group of healthy young female athletes. 相似文献
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Causal inference in mediation analysis offers counterfactually based causal definitions of direct and indirect effects, drawing on research by Robins, Greenland, Pearl, VanderWeele, Vansteelandt, Imai, and others. This type of mediation effect estimation is little known and seldom used among analysts using structural equation modeling (SEM). The aim of this article is to describe the new analysis opportunities in a way that is accessible to SEM analysts and show examples of how to perform the analyses. An application is presented with an extension to a latent mediator measured with multiple indicators. 相似文献
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Herbert W. Marsh Bengt Muthén Tihomir Asparouhov Oliver Lüdtke Alexander Robitzsch Alexandre J. S. Morin 《Structural equation modeling》2013,20(3):439-476
This study is a methodological-substantive synergy, demonstrating the power and flexibility of exploratory structural equation modeling (ESEM) methods that integrate confirmatory and exploratory factor analyses (CFA and EFA), as applied to substantively important questions based on multidimentional students' evaluations of university teaching (SETs). For these data, there is a well established ESEM structure but typical CFA models do not fit the data and substantially inflate correlations among the nine SET factors (median rs = .34 for ESEM, .72 for CFA) in a way that undermines discriminant validity and usefulness as diagnostic feedback. A 13-model taxonomy of ESEM measurement invariance is proposed, showing complete invariance (factor loadings, factor correlations, item uniquenesses, item intercepts, latent means) over multiple groups based on the SETs collected in the first and second halves of a 13-year period. Fully latent ESEM growth models that unconfounded measurement error from communality showed almost no linear or quadratic effects over this 13-year period. Latent multiple indicators multiple causes models showed that relations with background variables (workload/difficulty, class size, prior subject interest, expected grades) were small in size and varied systematically for different ESEM SET factors, supporting their discriminant validity and a construct validity interpretation of the relations. A new approach to higher order ESEM was demonstrated, but was not fully appropriate for these data. Based on ESEM methodology, substantively important questions were addressed that could not be appropriately addressed with a traditional CFA approach. 相似文献
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Mixture modeling is a widely applied data analysis technique used to identify unobserved heterogeneity in a population. Despite mixture models' usefulness in practice, one unresolved issue in the application of mixture models is that there is not one commonly accepted statistical indicator for deciding on the number of classes in a study population. This article presents the results of a simulation study that examines the performance of likelihood-based tests and the traditionally used Information Criterion (ICs) used for determining the number of classes in mixture modeling. We look at the performance of these tests and indexes for 3 types of mixture models: latent class analysis (LCA), a factor mixture model (FMA), and a growth mixture models (GMM). We evaluate the ability of the tests and indexes to correctly identify the number of classes at three different sample sizes (n = 200, 500, 1,000). Whereas the Bayesian Information Criterion performed the best of the ICs, the bootstrap likelihood ratio test proved to be a very consistent indicator of classes across all of the models considered. 相似文献
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Tomaž Bartol Danica Dolničar Bojana Boh Podgornik Blaž Rodič Tihomir Zoranović 《The Journal of Academic Librarianship》2018,44(3):374-382
The aim was to assess the information literacy (IL) of 310 first- and second-year students enrolled in nine different study programs at the School of Agriculture (Faculty of Agriculture), Novi Sad, Serbia, using an adapted version of a validated IL test (ILT) in an e-environment. Because the school does not provide systematic IL education, another purpose was to raise awareness of the importance of such instruction. ILT results were assessed according to five ACRL (Association of College & Research Libraries) standards, as well as three cognitive levels adapted from Bloom's taxonomy. The mean ILT score was 46.35%. Students were most successful in information evaluation and information need identification, and least successful in legal/ethical issues and information use. As expected, IL skills increase from the first to second year of study. Cognitive skills also increase, except for the highest level (applying knowledge), where all student groups are weak. Different study programs attract students with disparate knowledge/skill levels gained during secondary education, where some groups of first-year students may outperform second-year students in both IL and cognitive abilities. It is thus important to offer IL education to all students in order to provide a basis for more balanced academic progress. 相似文献
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In this article we describe a structural equation modeling (SEM) framework that allows nonnormal skewed distributions for the continuous observed and latent variables. This framework is based on the multivariate restricted skew t distribution. We demonstrate the advantages of skewed SEM over standard SEM modeling and challenge the notion that structural equation models should be based only on sample means and covariances. The skewed continuous distributions are also very useful in finite mixture modeling as they prevent the formation of spurious classes formed purely to compensate for deviations in the distributions from the standard bell curve distribution. This framework is implemented in Mplus Version 7.2. 相似文献
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This article examines the problem of specification error in 2 models for categorical latent variables; the latent class model and the latent Markov model. Specification error in the latent class model focuses on the impact of incorrectly specifying the number of latent classes of the categorical latent variable on measures of model adequacy as well as sample reallocation to latent classes. The results show that the clarity of remaining latent classes, as measured by the entropy statistic depends on the number of observations in the omitted latent class—but this statistic is not reliable. Specification error in the latent Markov model focuses on the transition probabilities when a longitudinal Guttman process is incorrectly specified. The findings show that specifying a longitudinal Guttman process that is not true in the population impacts other transition probabilities through the covariance matrix of the logit parameters used to calculate those probabilities. 相似文献