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81.
Semiotics is considered fundamental to an understanding of human–computer interaction, and of all computer artifacts. Informatics should therefore be viewed as technical semiotics (or semiotics engineering). In particular, interaction between human and computer is characterized by features of communication, a sort of communication, however, that lacks decisive communicative features. It must be identified as a process of pseudo-communication. Interaction is viewed as the coupling of two autonomous processes: a sign process (carried out by the human user) and a signal process (carried out by the computer). Software appears as a semiotic entity in a duplicate way: calculated and calculating, i.e. both as a result and agent of calculations. This dialectics characterizes the class of signs on the computer medium. Problems of software design (functionality and usability design) are specific problems of the coupling of sign and signal processes. 相似文献
82.
Stacy Alan W.; Flay Brian R.; Sussman Steve; Brown K. Stephen; Santi Susanne; Best J. Allan 《Canadian Metallurgical Quarterly》1990,2(4):442
The convergent validity of popularly used open-ended and closed-ended self-report measures of smoking was examined. Carbon monoxide (CO) samples were obtained from 11th-grade Canadian students as an independent method of assessing recent smoking. In addition to CO, 5 known psychosocial correlates of smoking (attitude, subjective norm, risk taking, best friend's smoking, and other friends' smoking) were used to estimate convergence with the self-report smoking indices. Results indicate that both simple closed-ended scales, with only a few response options, and more continuous, open-ended measures performed about equally as well as correlates of CO and the psychosocial measures, but only if the open-ended scales were subjected to a normalizing transformation to optimize their convergence. After this transformation was performed, convergence depended more on the time-span covered by the self-report indices than on the open-ended/closed-ended distinction. Implications of these results for different assessment goals were discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Perkins Kenneth A.; Epstein Leonard H.; Pastor Susanne 《Canadian Metallurgical Quarterly》1990,58(1):121
Caloric intake, resting metabolic rate (RMR), leisure-time physical activity, and sensitivity and preference for sweet taste were prospectively examined in 7 female smokers across 3 weeks during periods of normal smoking (Week 1), complete cessation (Week 2), and resumption of smoking (Week 3). Energy balance changed significantly across weeks, as caloric intake increased (largely as a result of alcohol consumption) and RMR decreased during cessation, followed by decreased caloric intake and increased RMR with resumption of smoking. Activity and taste sensitivity and preference remained unchanged. Smoking cessation may thus cause rapid change in energy balance, which is quickly reversed on resumption of smoking. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Susanne Liemersdorf Ralf Riedel Jürgen Oberle 《Journal of the American Ceramic Society》2008,91(1):325-328
Silicon oxycarbide (SiOC)-based ceramics were synthesized by pyrolysis of a commercial polysiloxane containing MoSi2 and ceramic filler particles. The influence of different gas atmospheres on the chemical composition and on the phase formation of the filled Si–O–C ceramic during the pyrolysis process up to elevated temperatures of above 1200°C has been studied. The pyrolysis gas composition in the furnace during pyrolysis was measured with an in situ gas analyzer. Both the core and the surface of bulk samples were investigated with respect to composition in order to take the changes on the rim area of the specimens into account. The influence of hydrogen gas on the compositional gradient of the resulting ceramic material was derived from samples investigated by polarization microscopy, X-ray diffraction (XRD), and micro-XRD (μ-XRD). 相似文献
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Anke Gundula Roth Susanne Redmer Christoph Arenz Prof. Dr. 《Chembiochem : a European journal of chemical biology》2009,10(14):2367-2374
The different mammalian sphingomyelinases are involved in cell regulation, apoptosis and inflammatory events. Recent reports suggest pharmacological potential especially for inhibitors of the acid sphingomyelinase. Phosphatidyl inositol‐3,5bisphosphate (PtdIns3,5P2) is the most potent selective acid sphingomyelinase inhibitor known to date. In the present study, we synthesized analogues of PtdIns3,5P2 for initial structure–activity‐relationship (SAR) studies. We identified an inhibitor that is easy to synthesize, that has superior chemical and biophysical properties when compared to PtdIns3,5P2 and that should be stable against virtually all phospholipases. Last but not least, the new inhibitor partially protected cells from dexamethasone‐induced cell death. 相似文献
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Dr. Kornelia Hardes Dr. Gero L. Becker Dr. Yinghui Lu Dr. Sven O. Dahms Susanne Köhler Dr. Wolfgang Beyer Prof. Kirsten Sandvig Dr. Hiroyuki Yamamoto Prof. Iris Lindberg Lisa Walz Dr. Veronika von Messling Dr. Manuel E. Than Prof. Wolfgang Garten Prof. Torsten Steinmetzer 《ChemMedChem》2015,10(7):1218-1231
New peptidomimetic furin inhibitors with unnatural amino acid residues in the P3 position were synthesized. The most potent compound 4‐guanidinomethyl‐phenylacteyl‐Arg‐Tle‐Arg‐4‐amidinobenzylamide (MI‐1148) inhibits furin with a Ki value of 5.5 pM . The derivatives also strongly inhibit PC1/3, whereas PC2 is less affected. Selected inhibitors were tested in cell culture for antibacterial and antiviral activity against infectious agents known to be dependent on furin activity. A significant protective effect against anthrax and diphtheria toxin was observed in the presence of the furin inhibitors. Furthermore, the spread of the highly pathogenic H5N1 and H7N1 avian influenza viruses and propagation of canine distemper virus was strongly inhibited. Inhibitor MI‐1148 was crystallized in complex with human furin. Its N‐terminal guanidinomethyl group in the para position of the P5 phenyl ring occupies the same position as that found previously for a structurally related inhibitor containing this substitution in the meta position, thereby maintaining all of the important P5 interactions. Our results confirm that the inhibition of furin is a promising strategy for a short‐term treatment of acute infectious diseases. 相似文献