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21.
Michel Ferrari Michelene T. H. Chi 《International Journal of Science Education》2013,35(10):1231-1256
Unlike some pivotal ideas in the history of science, the basic notion of natural selection is remarkably simple and so one might expect most students to easily grasp the basic principles of the Darwinian theory; yet many students nevertheless have difficulty understanding Darwinian evolution. We suggest that misconceptions about natural selection arise from mistaken categorization. Our thesis for explaining students’ failure to understand this concept or evolution in general is not that they necessarily fail to understand individual Darwinian principles; rather, they often fail to understand the ontological features of equilibration processes, of which evolution is one instance. They thus attribute the evolutionary process in general, and natural selection in particular, with event‐like properties. For example, naive students appear to focus on the idea of survival of the fittest, but embed this idea within an event ontology that involves actors struggling to overcome obstacles and achieve goals. Results showed that most naive subjects’ evolutionary explanations reflected an event ontology. Furthermore, event ontology attributes were positively correlated with non‐Darwinian explanations; by contrast, equilibration attributes, when present, were positively correlated with key Darwinian principles. These findings suggest that students would greatly benefit from science instruction that emphasized the underlying ontology of modern evolutionary theory. 相似文献
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Gruson D Ahn SA Rousseau MF 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2011,21(3):254-263
Heart failure (HF) is a frequent chronic disease in elderly people and represents a major health and economic burden. The accurate diagnosis of HF and the identification of high risk patients is mandatory to select the appropriate therapy and care. HF is associated to cardiac remodeling and inflammation and to the release of neurohormones. If natriuretic peptides remain the biomarkers of choice for the diagnosis and the prognosis of HF, several biomarkers related to cardiac remodeling and inflammation are available for testing and may add valuable information for the risk estimation of HF patients and for the selection of the most appropriated therapy. Furthermore, the quest for new efficient biomarkers of cardiac remodeling and inflammation is still ongoing and new candidates have been identified for a potential use in daily clinical practices. However, before their potential translation to routine parameters several challenges ranging form the analytical validation to the cost-effectiveness estimation should be considered. 相似文献
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Dimov N Muñoz L Carot-Sans G Verhoeven ML Bula WP Kocer G Guerrero A Gardeniers HJ 《Biomicrofluidics》2011,5(3):34102-3410212
To prepare a biosynthetic module in an infochemical communication project, we designed a silicon/glass microreactor with anti-adsorption polyelectrolyte multilayer coating and immobilized alcohol acetyl transferase (atf), one of the key biosynthetic enzymes of the pheromone of Spodoptera littoralis, on agarose beads inside. The system reproduces the last step of the biosynthesis in which the precursor diene alcohol (Z,E)-9,11-tetradecadienol is transformed into the major component (Z,E)-9,11-tetradecadienyl acetate. The scope of this study was to analyze and implement a multilayer, anti-adsorption coating based on layer-by-layer deposition of polyethylenimine/dextransulfate sodium salt (PEI/DSS). The multilayers were composed of two PEI with molecular weights 750 and 1.2 kDa at pH 9.2 or 6.0. Growth, morphology, and stability of the layers were analyzed by ellipsometry and atomic force microscopy (AFM). The anti-adsorption functionality of the multilayer inside the microreactor was validated. The activity of His(6)-(atf) was measured by gas chromatography coupled to mass spectrometer (GC-MS). 相似文献
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Michel Arrouays 《Higher Education in Europe》1996,21(2-3):49-55
The TEMPUS/PHARE Multilateral Programme was initiated in 1990 by the European Communities with a view to improving training by means of the structural reform of the higher education systems in the central and eastern European countries. The results are now widely visible. The question to be asked is whether or not these results are limited solely to the educational field or whether the improvement of training has not also had an impact on society and the economy. In the particular case of the central and eastern European countries that are currently moving from one social system to another, the task is one of finding out in what respects and to what extent the changes in the higher education systems have contributed to this transition. 相似文献
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