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91.
92.
Stefanie Vanbecelaere Katrien Van den Berghe Frederik Cornillie Delphine Sasanguie Bert Reynvoet Fien Depaepe 《Journal of Computer Assisted Learning》2020,36(4):502-513
For the training of academic skills, digital educational games with integrated adaptivity are promising. Adaptive games are considered superior to non-adaptive games, because they constantly assess children's performance, and accordingly adapt the difficulty of the tasks corresponding to the children's individual level. However, empirical evidence with regard to the effectivity of adaptive compared to non-adaptive games is limited. A study was conducted with 191 children from the third year of Kinder garten who were enrolled in one of three conditions, that is, playing an adaptive version of the reading game (RG), a non-adaptive version of the RG or training with pen-and-paper exercises. In all three conditions, children trained emergent reading (phonological awareness and letter knowledge) once a week for 30 min over a period of 5 weeks. Children's performance on cognitive (phonological awareness, letter knowledge, reading fluency) and non-cognitive (motivation, self-concept) factors was assessed. Results revealed a significant improvement in phonological awareness and letter knowledge in all conditions. However, no differences between the conditions were observed with respect to children's improvement on phonological awareness and letter knowledge or on their post-test scores for reading fluency. With regard to motivation and self-concept, again, no differences in these non-cognitive factors were observed across conditions. 相似文献
93.
Forster Yannick Hergeth Sebastian Naujoks Frederik Krems Josef F. Keinath Andreas 《Cognition, Technology & Work》2020,22(4):703-720
Cognition, Technology & Work - For a successful market introduction of Level 3 Automated Driving Systems (L3 ADS), a careful evaluation of human–machine interfaces (HMIs) is necessary.... 相似文献
94.
Wetting measurements as a tool to predict the thermoplastic/thermoset rubber compatibility in two‐component injection molding 下载免费PDF全文
Gert‐Jan Bex David Seveno Jozefien De Keyzer Frederik Desplentere Albert Van Bael 《应用聚合物科学杂志》2018,135(13)
Recently a novel two‐component injection molding process has been developed combining thermoplastics with thermoset rubbers. Since the adhesion strength between the two materials strongly depends on the combination of a specific thermoplastic and a thermoset rubber, there is a need to predict their compatibility, defined as the formation of a strong interface. In this study, the wetting behavior of molten thermoplastics on rubber substrates is used to predict their compatibility since wetting is an essential step in the formation of a strong interface. Contact angle measurements at high temperatures showed that the wetting of polypropylene and polyethylene is the best in combination with ethylene propylene diene monomer rubber while nitrile rubber is best wetted by polycarbonate. The subsequent two‐component injection molding tests confirm that it is possible to combine these materials. Material combinations with a poor wetting behavior on the other hand are not suitable for two‐component injection molding. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46046. 相似文献
95.
Structure–Activity Relationship Studies on (R)‐PFI‐2 Analogues as Inhibitors of Histone Lysine Methyltransferase SETD7 下载免费PDF全文
Danny C. Lenstra Dr. Eddy Damen Dr. Ruben G. G. Leenders Dr. Richard H. Blaauw Prof. Dr. Floris P. J. T. Rutjes Dr. Anita Wegert Dr. Jasmin Mecinović 《ChemMedChem》2018,13(14):1405-1413
SETD7 is a histone H3K4 lysine methyltransferase involved in human gene regulation. Aberrant expression of SETD7 has been associated with various diseases, including cancer. Therefore, SETD7 is considered a good target for the development of new epigenetic drugs. To date, few selective small‐molecule inhibitors have been reported that target SETD7, the most potent being (R)‐PFI‐2. Herein we report structure–activity relationship studies on (R)‐PFI‐2 and its analogues. A library of 29 structural analogues of (R)‐PFI‐2 was synthesized and evaluated for inhibition of recombinantly expressed human SETD7. The key interactions were found to be a salt bridge and a hydrogen bond formed between (R)‐PFI‐2′s NH2+ group and SETD7′s Asp256 and His252 residue, respectively. 相似文献
96.
P. M. Frederik M. C. A. Stuart P. H. H. Bomans W. M. Busing K. N. J. Burger A. J. Verkleij 《Journal of microscopy》1991,161(2):253-262
We investigated the possibility of vitrifying temperature-sensitive lipid phases as well as (small) biological specimens. From a suspension of unilamellar vesicles, prepared from dipalmitoyl-phosphatidylcholine (DPPC), thin aqueous films were formed at various temperatures. With cryo-electron microscopy vesicles were found to be smooth, rippled and faceted or faceted only, depending on the temperature of thin-film formation (318, 312 and 296 K respectively). The morphology and the electron diffraction patterns indicate that membranes can by physically fixed by vitrification in their high-temperature configuration and studied at low temperature by cryo-electron microscopy. This finding suggests that it may also be possible to preserve, in their original state, the more complex membrane systems found in living organisms by initiating rapid-cooling at a physiological temperature. This was explored by vitrification of thin films formed on specimen grids with (human) blood platelets adhering to collagen fibres. Low-temperature observation with an acceleration voltage of 120 kV revealed subcellular details. More details were observed when using higher accelerating voltages (200 and 300 kV) of the electron beam. The results presented in this paper illustrate the great potential of cryo-electron microscopy in the study of membrane dynamics, both in relatively simple model membrane systems and in more complex biological membrane systems. 相似文献
97.
Frederik Kotz Norbert Schneider Andreas Striegel Andre Wolfschläger Nico Keller Matthias Worgull Werner Bauer Dieter Schild Marcel Milich Christian Greiner Dorothea Helmer Bastian E. Rapp 《Advanced materials (Deerfield Beach, Fla.)》2018,30(22)
Fused silica glass is one of the most important high‐performance materials for scientific research, industry, and society. However due to its high chemical and thermal resistance as well as high hardness, fused silica glass is notoriously difficult to structure. This work introduces Glassomer, a solid nanocomposite, which can be structured using polymer molding and subtractive technologies at submicrometer resolution. After polymer processing Glassomer is turned into optical grade fused silica glass during a final heat treatment. The resulting glass has the same optical transparency as commercial fused silica and a smooth surface with a roughness of a few nanometers. This work makes high‐performance fused silica glass components accessible to high‐throughput fabrication technologies and will enable numerous optical, photonic and medical applications in science and industry. 相似文献
98.
Exploiting Noncovalent Interactions in an Imine‐Based Covalent Organic Framework for Quercetin Delivery 下载免费PDF全文
99.
Frederik De Grove Cédric Courtois Jan Van Looy 《Journal of Computer-Mediated Communication》2015,20(3):346-361
Over the past decades, digital games have continued to extend their audience as they moved into the cultural mainstream. Despite this fact, however, only a portion of those who play games consider themselves a gamer. Drawing on insights from social identity theory, this study explores the factors that contribute to why people attribute a gamer identity to self or others. It does so by considering 2 sites of identity construction: the social context of players and the broader cultural milieu. Results suggest that a gamer identity is first and foremost associated with stereotypical behaviors that find their origin in a consumption logic. Friendship networks, however, provide an important environment in which a gamer identity can be performed. 相似文献
100.
Frederik S. O. Fritzsch Lars M. Blank Christian Dusny Andreas Schmid 《Microfluidics and nanofluidics》2017,21(8):130
Microflow cytometry, including robust alignment, separation, and trapping of living cells, is on the verge of commercialization. Yet, the necessary equipment is frequently not applicable to certain biological questions as the products have been specifically developed for particular cell types. We present a versatile cell handling technology based on single miniaturized octupoles that enables the physical manipulation of a broad variety of different cell types via controlled negative dielectrophoresis force fields. The octupole technology allows contactless and time-resolved cell analysis in physicochemical controlled microenvironments. Contactless cell manipulation and trapping with the octupole technology were shown to be independent of cell size and morphology. This was demonstrated with nine different cell types of technical and medical relevance, ranging from motile bacteria over yeast and small platelets (thrombocytes) up to large cancer cells. We also demonstrate applications of octupole cytometry for controlled analyses of mechano-elastic properties of single cells, contactless cultivation and perfusion for perturbation studies, as well as studying the interaction of different cell types in physical proximity. These examples prove the miniaturized octupole format as a versatile, noninvasive, and robust tool for microfluidic single cell cytometry that complements existing hydrodynamic, optical, and acoustic technologies. 相似文献