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Egidio Robusto Luca Stefanutti Pasquale Anselmi 《Journal of Educational Measurement》2010,47(3):373-394
Within the theoretical framework of knowledge space theory, a probabilistic skill multimap model for assessing learning processes is proposed. The learning process of a student is modeled as a function of the student's knowledge and of an educational intervention on the attainment of specific skills required to solve problems in a knowledge domain. Model parameters are initial probabilities of the skills, effects of learning objects on gaining and losing the skills, and careless error and lucky guess probabilities of the problems. An empirical application shows that the model is effective in assessing knowledge and effectiveness of educational intervention at both classroom and student levels. Practical implications for teaching and learning are discussed. 相似文献
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Luca Guzzardi 《Science & Education》2014,23(6):1269-1291
This paper discusses Ernst Mach’s interpretation of the principle of energy conservation (EC) in the context of the development of energy concepts and ideas about causality in nineteenth-century physics and theory of science. In doing this, it focuses on the close relationship between causality, energy conservation and space in Mach’s antireductionist view of science. Mach expounds his thesis about EC in his first historical-epistemological essay, Die Geschichte und die Wurzel des Satzes von der Erhaltung der Arbeit (1872): far from being a new principle, it is used from the early beginnings of mechanics independently from other principles; in fact, EC is a pre-mechanical principle which is generally applied in investigating nature: it is, indeed, nothing but a form of the principle of causality. The paper focuses on the scientific-historical premises and philosophical underpinnings of Mach’s thesis, beginning with the classic debate on the validity and limits of the notion of cause by Hume, Kant, and Helmholtz. Such reference also implies a discussion of the relationship between causality on the one hand and space and time on the other. This connection plays a major role for Mach, and in the final paragraphs its importance is argued in order to understand his antireductionist perspective, i.e. the rejection of any attempt to give an ultimate explanation of the world via reduction of nature to one fundamental set of phenomena. 相似文献
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Gabriel Lima-Oliveira Gian Luca Salvagno Giuseppe Lippi Elisa Danese Matteo Gelati Martina Montagnana Geraldo Picheth Gian Cesare Guidi 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(3):343-349
Background:
Presently the necessity of fasting time for coagulation tests is not standardized. Our hypothesis is that this can harm patient safety. This study is aimed at evaluating whether a light meal (i.e. breakfast) can jeopardize laboratory coagulation tests.Materials and methods:
A blood sample was firstly collected from 17 fasting volunteers (12 h). Immediately after blood collection, the volunteers consumed a light meal. Then samples were collected at 1, 2 and 4 h after the meal. Coagulation tests included: activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen (Fbg), antithrombin III (AT), protein C (PC) and protein S (PS). Differences between samples were assessed by Wilcoxon ranked-pairs test. The level of statistical significance was set at P < 0.05. Mean % differences were determined and differences between and baseline and 1, 2 and 4h samples were compared with reference change value (RCV).Results:
A significantly higher % activity of AT was observed at 1 h and 4 h after meal vs. baseline specimen [113 (104–117) and 111 (107–120) vs. 109 (102–118), respectively; P = 0.029 and P = 0.016]. APTT at 2 h was found significantly lower than baseline samples [32.0 (29.9–34.8) vs. 34.1 (32.2–35.2), respectively; P = 0.041]. The results of both Fbg and PS tests were not influenced by a light meal. Furthermore, no coagulation tests had significant variation after comparison with RCV.Conclusion:
A light meal does not influence the laboratory coagulation tests we assessed, but we suggest that the laboratory quality managers standardize the fasting time for all blood tests at 12 hours, to completely metabolize the lipids intake. 相似文献56.
The paper explores two pathways that are crucial for making knowledge economically useful – knowledge systematisation and knowledge reconfiguration – and analyses how their interplay enables the emergence of a new business function or activity. Knowledge systematisation is the abstraction and diffusion of operative principles to the effect of expanding to broader remits practices that had been initially conceived for a narrow purpose. Knowledge reconfiguration involves the conversion and formalisation of these novel practices within existing firm and industry organisation. Using the design activity as a lens, and drawing on primary and secondary interviews and archival data on the home furnishing sectors in Italy, our case study articulates the processes that facilitate the abstraction of general rules from novel practices and the changes that are necessary, both within firm and industry organisation, to foster their diffusion. 相似文献
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Lippi G Cervellin G Aloe R Montagnana M Salvagno GL Guidi GC 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(1):127-129
Introduction:
The measurement of cardiospecific troponins is pivotal in the diagnostic and prognostic approach of patients with suspected acute myocardial infarction (AMI). However, no information is available on the commutability of results between the novel highly-sensitive (HS) troponin T (TnT) and I (TnI) immunoassays.Materials and methods:
The study population consisted in 47 consecutive patients presenting at the emergency department (ED) of the Academic Hospital of Parma with suspected AMI. TnI was measured with the novel prototype Beckman Coulter HS-AccuTnI immunoassay on Access 2, whereas TnT was measured with the Roche HS-TnT immunoassay on Cobas.Results:
Eight out of the 47 patients (17%) were finally diagnosed as having an AMI. The overall correlation between TnT and TnI for total patient group was acceptable (r = 0.944; P < 0.01). Nevertheless, when the analysis of data was carried out in separate groups according to the final diagnosis of AMI, two different equation results were obtained, i.e., HS-TnT = HS-AccuTnI × 0.349 + 20 (r = 0.823; P < 0.01) in non-AMI patients, and HS-TnT = HS-AccuTnI × 0.134 + 67 (r = 0.972; P < 0.01) in those with AMI.Conclusions:
This study suggests the existence of two biological relationships between TnI and TnT in plasma, depending on the source of release from the myocardium. Moreover, the non-commutability of data between HS-TnT and HS-AccuTnI jeopardizes the clinical decision making, makes it impossible to calculate the delta or reference change value using the two biomarkers and to finally establish a reliable kinetics of troponin release from the injured myocardium. 相似文献59.
We investigate if and to what extent the receipt of a “selective” subsidy – a public subsidy awarded through a competitive procedure – helps new technology-based firms (NTBFs) to access R&D alliances. In particular, we theoretically enquire and empirically analyze which founding team-level characteristics allow NTBFs to: i) get a selective subsidy; and ii) access an R&D alliance with another firm or a public research organization/university, once the subsidy is awarded. We use a sample of 902 NTBFs that operate in Italy, where industrial policy has never had an explicit and exclusive mandate neither for targeting NTBFs nor for easing their access to R&D networks. By means of several identification strategies and estimation methods, our results point to the relevance of selective subsidies in facilitating NTBFs to enter R&D alliances, independently from the objective of the policy measure. Second, founders’ technical education figures as a key determinant to get the first selective subsidy. Finally, founders’ previous industry-specific work experience allows NTBFs to better exploit the selective subsidy, by positively moderating the impact of the subsidy on the likelihood to establish a corporate R&D alliance. 相似文献
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It is often argued that small–medium enterprises (SMEs) do not manage knowledge the same way as large firms, but may need appropriate approaches to capture and exploit external knowledge effectively. This paper compares two opposite approaches to knowledge management (KM): one is called ‘deliberate’ or ‘planned’, and the other ‘emergent’. These approaches are analysed with reference to the management of knowledge pertaining to client–supplier relationships, which are particularly important in the case of small companies providing knowledge-intensive business services (KIBS). A case study of a small KIBS company is illustrated, which has developed two different projects, based on different approaches to KM, for managing knowledge referring to clients. The case shows that, for a small company, an emergent approach to KM can be more suitable than a deliberate one for managing such knowledge. The implications of this result for KM research and practice are then examined. 相似文献