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101.
Gennaro Costagliola Andrea De Lucia Filomena Ferrucci Carmine Gravino Giuseppe Scanniello 《Journal of Visual Languages and Computing》2008,19(6):721-737
In this paper, we present a usability study aiming at assessing a visual language-based tool for developing adaptive e-learning processes. The tool implements the adaptive self-consistent learning object SET (ASCLO-S) visual language, a special case of flow diagrams, to be used by instructional designers to define classes of learners through stereotypes and to specify the more suited adaptive learning process for each class of learners. The usability study is based on the combined use of two techniques: a questionnaire-based survey and an empirical analysis. The survey has been used to achieve feedbacks from the subjects’ point of view. In particular, it has been useful to capture the perceived usability of the subjects. The outcomes show that both the proposed visual notation and the system prototype are suitable for instructional designers with or without experience on the computer usage and on tools for defining e-learning processes. This result is further confirmed by the empirical analysis we carried out by analysing the correlation between the effort to develop adaptive e-learning processes and some measures suitable defined for those processes. Indeed, the empirical analysis revealed that the effort required to model e-learning processes is not influenced by the experience of the instructional designer with the use of e-learning tools, but it only depends on the size of the developed process. 相似文献
102.
Not all relevant instructional information comes in the form of spoken words. In the present study, the authors examine multiple modalities of nonspoken forms of representation—specifically gestures, pictures, objects, and writing—used by 3 teachers in 3 yrs of 1st-grade math lessons. Teachers frequently used visually based modalities of representation and tended to produce combinations of representational forms rather than isolated representations. There were individual differences in their preference for representation types. Teachers used representations to accompany important spoken terms and to respond to student confusion. With nonspoken representations, teachers conveyed information critical to the explanation of mathematical concepts. Students must attend to the visual as well as vocal means of expressing information to gain access to all of the information presented in mathematics lessons. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Kenny David A.; Mannetti Lucia; Pierro Antonio; Livi Stefano; Kashy Deborah A. 《Canadian Metallurgical Quarterly》2002,83(1):126
The authors elaborate the complications and the opportunities inherent in the statistical analysis of small-group data. They begin by discussing nonindependence of group members' scores and then consider standard methods for the analysis of small-group data and determine that these methods do not take into account this nonindependence. A new method is proposed that uses multilevel modeling and allows for negative nonindependence and mutual influence. Finally, the complications of interactions, different group sizes, and differential effects are considered. The authors strongly urge that the analysis model of data from small-group studies should mirror the psychological processes that generate those data. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
105.
Kruglanski Arie W.; Shah James Y.; Pierro Antonio; Mannetti Lucia 《Canadian Metallurgical Quarterly》2002,83(3):648
Four studies explored the relation between members' need for cognitive closure and their feelings toward groups. It was found that high (vs. low) need for closure individuals liked in-groups and out-groups more as function of the degree to which their membership was perceived as homogeneous (Studies 1-4), provided it was also self-similar (Studies 3 and 4). These results are discussed in terms of the relation between need for closure and homogeneous (vs. heterogeneous) groups' apparent potential as "closure providers." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
The Phosphoinositide 3‐Kinase Signaling Pathway is Involved in the Control of Modified Low‐Density Lipoprotein Uptake by Human Macrophages
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Daryn R. Michael Thomas S. Davies Lucia Laubertová Hayley Gallagher Dipak P. Ramji 《Lipids》2015,50(3):253-260
The transformation of macrophages into lipid‐loaded foam cells is a critical early event in the pathogenesis of atherosclerosis. Both receptor‐mediated uptake of modified LDL, mediated primarily by scavenger receptors‐A (SR‐A) and CD36 along with other proteins such as lipoprotein lipase (LPL), and macropinocytosis contribute to macrophage foam cell formation. The signaling pathways that are involved in the control of foam cell formation are not fully understood. In this study, we have investigated the role of phosphoinositide 3‐kinase (PI3K) in relation to foam cell formation in human macrophages. The pan PI3K inhibitor LY294002 attenuated the uptake of modified LDL and macropinocytosis, as measured by Lucifer Yellow uptake, by human macrophages. In addition, the expression of SR‐A, CD36 and LPL was attenuated by LY294002. The use of isoform‐selective PI3K inhibitors showed that PI3K‐β, ‐γ and ‐δ were all required for the expression of SR‐A and CD36 whereas only PI3K‐γ was necessary in the case of LPL. These studies reveal a pivotal role of PI3K in the control of macrophage foam cell formation and provide further evidence for their potential as therapeutic target against atherosclerosis. 相似文献
107.
Identification of Aminoimidazole and Aminothiazole Derivatives as Src Family Kinase Inhibitors
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Dr. Cinzia Maria Francini Dr. Anna Lucia Fallacara Dr. Roberto Artusi Dr. Laura Mennuni Dr. Alessia Calgani Dr. Adriano Angelucci Prof. Silvia Schenone Prof. Maurizio Botta 《ChemMedChem》2015,10(12):2027-2041
Src family kinases (SFKs) are a family of non‐receptor tyrosine kinases (TKs) implicated in the regulation of many cellular processes. The aberrant activity of these TKs has been associated with the growth and progression of cancer. In particular, c‐Src is overexpressed or hyperactivated in a variety of solid tumors and is most likely a strong promoting factor for the development of metastasis. Herein, the synthesis of new 4‐aminoimidazole and 2‐aminothiazole derivatives and their in vitro biological evaluation are described for their potential use as SFK inhibitors. Initially, 2‐aminothiazole analogues of dasatinib and 4‐aminoimidazole derivatives were synthesized and tested against the SFKs Src, Fyn, Lyn, and Yes. Five hits were identified as the most promising compounds, with Ki values in the range of 90–480 nm . A combination of molecular docking, homology modeling, and molecular dynamics were then used to investigate the possible binding mode of such compounds within the ATP binding site of the SFKs. Finally, the antiproliferative activities of the best candidates were evaluated against SH‐SY5Y and K562 cell lines. Compound 3 b [2‐(4‐{2‐methyl‐6‐[(5‐phenylthiazol‐2‐yl)amino]pyrimidin‐4‐yl}piperazin‐1‐yl)ethanol] was found to be the most active inhibitor. 相似文献
108.
Lucia Marseglia Gabriella D’Angelo Sara Manti Salvatore Aversa Teresa Arrigo Russel J. Reiter Eloisa Gitto 《International journal of molecular sciences》2015,16(1):1209-1220
Exogenous melatonin is used in a number of situations, first and foremost in the treatment of sleep disorders and jet leg. However, the hypnotic, antinociceptive, and anticonvulsant properties of melatonin endow this neurohormone with the profile of a drug that modulates effects of anesthetic agents, supporting its potential use at different stages during anesthetic procedures, in both adults and children. In light of these properties, melatonin has been administered to children undergoing diagnostic procedures requiring sedation or general anesthesia, such as magnetic resonance imaging, auditory brainstem response tests and electroencephalogram. Controversial data support the use of melatonin as anxiolytic and antinociceptive agents in pediatric patients undergoing surgery. The aim of this review was to evaluate available evidence relating to efficacy and safety of melatonin as an analgesic and as a sedative agent in children. Melatonin and its analogs may have a role in antinociceptive therapies and as an alternative to midazolam in premedication of adults and children, although its effectiveness is still controversial and available data are clearly incomplete. 相似文献
109.
Investigating the Role of Conformational Effects on Laccase Stability and Hyperactivation under Stress Conditions
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Dr. Valerio Ferrario Dr. Alexey Chernykh Federica Fiorindo Dr. Marina Kolomytseva Dr. Loris Sinigoi Dr. Nina Myasoedova Dr. Diana Fattor Prof. Dr. Cynthia Ebert Prof. Dr. Ludmila Golovleva Prof. Dr. Lucia Gardossi 《Chembiochem : a European journal of chemical biology》2015,16(16):2365-2372
Fungal laccase from Steccherinum ochraceum 1833 displays remarkable stability under different harsh conditions: organic/buffer mixtures, thermal treatment, and microwave radiation. The behavior is particularly significant in the light of the sharp inactivation observed for two different fungal laccases. Laccase from S. ochraceum 1833 also displays hyperactivation under mild thermal treatment (60 °C). Molecular dynamics simulations at 80 °C explained how this laccase retains the geometry of the electron transfer pathway, thereby assuring electron transfer through the copper ions and thus maintaining its catalytic activity at high temperature. Spectroscopic studies revealed that the thermal activation corresponds to specific conformational changes in the protein. The results indicate that this laccase is potentially applicable under denaturing conditions that might be beneficial for the biotransformation of recalcitrant substrates. 相似文献
110.
Lucia Martínez-Latorre 《Carbon》2010,48(7):2047-48
A well-adhered layer of carbon nanofibers (CNFs) was grown on stainless steel microreactors by decomposition of a hydrocarbon over microreactors previously coated with Ni dispersed on alumina. In a previous work, we reported that the growth temperature and hydrocarbon (methane or ethane) modulated the morphology and size of the grown carbon species. Using ethane, the carbon yield increased dramatically for temperatures exceeding 898 K. At these temperatures some carbon protrusions arise, which plug microreactor channels and render the microreactor unsuitable for use. For methane at all the tested temperatures or for ethane at the lowest temperatures (853 and 873 K), the microreactor channels were covered completely by a uniform mat of entangled CNFs ready for catalytic use. Here, we show that the growth temperature and hydrocarbon can also control the primary structure of CNFs, either rolled graphitic planes parallel to the axis (multi-wall carbon nanotubes) or graphitic planes forming an angle with respect to the axis (fishbone type). 相似文献