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排序方式: 共有72条查询结果,搜索用时 15 毫秒
41.
Burin Debora I. Gonzalez Federico Martin Barreyro Juan Pablo Injoque-Ricle Irene 《Metacognition and Learning》2020,15(3):391-410
Metacognition and Learning - This study examined the contribution of self-reported metacognitive regulation of reading to expository digital text comprehension in an e-learning environment,... 相似文献
42.
This paper builds on agency and institutional theory to extend the analysis of the effects of ownership and control on R&D investments by considering the influence of different types of ownership and of institutional corporate governance systems. Our empirical analysis is based on a unique dataset of 1000 firms publicly-traded in six European countries (France, Germany, Italy, Norway, Sweden and the UK). Controlling for industry- and firm-level effects, our findings show that higher shareholding by families is negatively associated with R&D investment. Moreover, widely-held firms invest less in R&D in the United Kingdom than in Continental European countries, thus suggesting the existence of a greater pressure towards the reduction of R&D in market-based governance systems. The results are robust against possible sample selection biases due to firms’ discretional R&D disclosure. 相似文献
43.
Martino Colonna Nicola Pazi Matteo Moncalero Claudio Gioia Federico De Bon Davide Giovanelli Elisabetta Farella 《Sports Engineering》2017,20(4):275-282
We have performed a study on the thermo-formation process of plastic shells of boots for winter sports. The aim of the work has been to determine how the process parameters can improve the ergonomic and thermal comfort for athletes and winter sports participants. We have found that the initial deformation and memory effect are strongly influenced by the type of thermoplastic material used, heating time and cooling procedure. We have also found that the ovens currently used for this process are not correctly designed to obtain an efficient heat transfer and, therefore, a heating time of at least 12 min is necessary to achieve an average deformation of more than 2 mm. The measure of the boot flexural stiffness has shown that there are no changes in the load–deflection behavior after the thermo-formation process of a ski boot made of thermoplastic polyurethane. We have also found that the thermo-formation process decreases the pressure on skier’s feet of more than five times and, therefore, improves the comfort of the skier. 相似文献
44.
We analyze art pricing in a unique dataset on Madrid inventories between 1600 and 1750. We estimate a price index for the Spanish art market that is used for a general historical analysis of art during this period, showing a large increase in the real price of paintings during the XVII century. Then we examine the price differential between domestic and foreign paintings: At the beginning of the century domestic production was priced substantially below imported paintings, but the price gap was gradually reduced during the century. We argue that such a price convergence was not the fruit of variations in real exchange rate, relative supply or home bias, but was associated with increasing prices for the new domestic painters of the XVII century. Increasing remuneration for painting may have induced artistic innovations by domestic producers and created the conditions for the development of the Siglo de Oro of Spanish art. 相似文献
45.
Western preschool children often assign ownership based on first possession and some theorists have proposed that this judgment might be an early emerging, innate bias. Five‐ to 9‐year‐olds (n = 112) from a small‐scale group in Kenya (Kikuyu) watched videotaped interactions of two women passing an object. The object's starting position and the women's gestures were varied. Use of the first possession heuristic increased with age, and 8‐ to 9‐year‐olds performed similarly to German 5‐year‐olds (n = 24). Starting position and gestures had no effect. A control study confirmed that 5‐year‐old Kikuyus (n = 20) understood the video material. The findings reveal that the first possession heuristic follows different developmental trajectories cross‐culturally and stress the role of children's sociocultural environment. 相似文献
46.
Rufino Mondejar María Mayor Reyes Enrique Melguizo Madrid Consuelo Caavate Solano Santiago Prez Ramos 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(2)
IntroductionTotal bilirubin tests are highly demanded in clinical laboratories. Since icteric index (I-index) has zero cost, we aimed to evaluate its clinical utility and cost-effectiveness to determine if total bilirubin is necessary to be tested. We took into account if haemolysis could interfere to icteric index determination.Material and methodsRetrospectively we reviewed I-index results in two cohorts (43,372 and 8507 non-haemolysed and haemolysed samples, respectively). All determinations were done using Alinity c chemistry analysers (Abbott Diagnostics). Receiver operating characteristic (ROC) curve was used to determine the optimal index cut-off to discriminate between normal and abnormal bilirubin concentration (20.5 µmol/L).ResultsThe ROC curve analysis suggested 21.4 µmol/L as the optimal I-index cut-off but differences in sensitivity and specificity were detected between patient derivation. For rejecting purpose, 15.4 µmol/L and 17.1 µmol/L I-index thresholds were selected based on patient derivation (inpatients and emergency room; and primary care and outpatients, respectively) with 97% sensitivity and 0.25% false negative results. Sensitivity was much lower in haemolysed samples. We selected 34.2 µmol/L I-index as threshold to detect hyperbilirubinemia with 99.7% specificity and 0.26% false positive results, independent of haemolysis. With the icteric index cut-offs proposed, we would save 66% of total bilirubin requested and analyse total bilirubin in around 2% of samples without total bilirubin requested.ConclusionsThis study supports the use of I-index to avoid bilirubin determination and to identify patients with hyperbilirubinemia. This work considers that the economic and test savings could help to increase the efficiency in clinical laboratories. 相似文献
47.
Considering that today’s students feel extremely more comfortable with computers than did earlier generations of students vis-à-vis the notion that, as a social category, they have become one of the most interesting topics in research papers and journals in the field of behavioral and social sciences since the 1950s (Batan 2002), their individual and collective experiences of information and communications technology (ICT) could be expected to create a portrait of accounts that might inform educational policy makers as to how their ICT needs and concerns could be better addressed through a more responsive and a well-defined IT-driven educational platform. The central question that this phenomenological study purported to answer was: “How does a select group of Filipino adolescents collectively experience information and communications technology (ICT)?” Findings of this study revealed that the individual and collective articulations, verbalizations, and musings of the 60 adolescents recruited from two regions in the Philippines exposed three distinct but interrelated conceptual zones of ICT, namely: the zone of technology perspective (ZTP), zone of technology power and efficacy (ZTPE), and zone of technology deficits (ZTD). Implications of the study are also discussed in the paper. “There is a demand for qualitative research with an insider perspective, as young voices appear not to have been sufficiently heard.” (Hauan and Heggli 2002:13) 相似文献
48.
The temporal generalization gradient produced by the peak-interval (PI) procedure reflects behavior under the control of positive
reinforcement for responding after the criterial time, but shows negligible discouragement for early responses. The lack of
consequences for premature responding may affect estimates of timing accuracy and precision in the PI procedure. In two experiments,
we sought to encourage more accurate timing in pigeons by establishing an opportunity cost for such responding. Concurrent
ratio and interval schedules of reinforcement reduced the dispersion of keypecking around the target time. A sequence of three
response-rate states (low-high-low) characterized performance in individual trials. Opportunity cost substantially reduced
the mean and standard deviation of the duration of the middle-high state that typically enveloped the target time, indicating
improved temporal acuity. We suggest a model as a first-order approximation to timing with opportunity cost. 相似文献
49.
Wine is one of the most important Italian export products, and Nebbiolo is one of the most respected Italian grapes. In the summer of 2007, a measurement campaign was carried out in a Nebbiolo vineyard located in Vezza d'Alba, near Cuneo, Italy. Using a gauge of trade gases and some other instruments, we recorded the stomatal conductance and also some physiological parameters useful for estimating the dependence of stomatal conductance on environmental variables. The goal of this experiment was improving the parameterization of grapevine evapotranspiration through the assessment of the stomatal conductance and, in particular, of the functional dependence of the stomatal conductance on the following variables: the photosynthetically active radiation, the atmospheric temperature, the atmospheric moisture deficit, and the carbon dioxide concentration. The observations allowed us to check and, in some cases, to adapt the existing general parameterizations found in literature. The results showed some significant differences with the existing parameterizations concerning the atmospheric temperature, the atmospheric moisture deficit, and the carbon dioxide concentration. The parameterizations obtained in this experiment, although referring to a specific plant and site (namely the Nebbiolo at Vezza d'Alba), could allow assessment of the best environmental conditions under which the Nebbiolo grapevine production is the best, and in future could be tested for other grapevines or climates. 相似文献
50.
Federico Mayor 《Higher Education in Europe》2004,29(4):491-494
The author considers in this article the ethical boundaries of knowledge, the challenges inherent in the improvement of international ethical and legal frameworks, and some of the ethically important moments of the past half‐century. Implications for higher education in the context of globalization are also considered, as are some of the new educational requirements of the knowledge‐driven economy and society. 相似文献