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Flood Hazards     
The phenomenon of virtual space is fundamental to the way human beings relate perceptually, behaviorally, and existentially to their world. Virtuality is the presence of what is not literally present, and it thus enables the immanence of building to be annealed to the past and future, analogous form, and hypothetical possibility. In sum, virtuality is synonymous with “architecture” proper, as opposed to building simple. Through the use of gesture, the non-present is made present and given a secret status ruled by a non-classical or “grotesque” order. The principle of our access to the virtual is based on the act of reading, where the movement from the actual to the virtual is simultaneously a spatial and a philosophical transformation. Reading is not simply the translation of phonetic or iconographic characters into their linguistic equivalents, but a restructuring of the space of appearance. The origins and evolution of this “space of reading” are characterized by a distinctive architecture, and the architecture of inhabitable spaces is conditioned by this distinctive architecture: the architecture of reading is the means of reading architecture.  相似文献   
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8-(Sulfostyryl)xanthine derivatives were synthesized as water-soluble A2A-selective adenosine receptor (AR) antagonists. meta- and para-sulfostyryl-DMPX (3,7-dimethyl-1-propargylxanthine) derivatives 11a and 11b exhibited high affinity to rat A2A-AR in submicromolar concentrations, and were 20- to 30-fold selective versus rat A1-AR. Styryl-DMPX derivatives were inactive at human A2B- and A3-AR. 1,3-Dipropyl-8-p-sulfostyrylxanthine (13) or only a 7-methyl derivative (14) showed similar (13) or higher (14) A2A affinity than 11a and 11b but showed no (13) or only a low degree (14) of selectivity versus A1-, A2B-, and A3-AR. The A2A-selective sulfostyryl-DMPX derivatives exhibit high water-solubility and may be useful research tools for in vivo studies.  相似文献   
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Lead titanate gels were prepared via sol–gel synthesis and dried either in supercritical carbon dioxide or isopropanol. Both types of aerogels were characterized by means of thermal analysis and transmission electron microscopy. Helium pycnometry and nitrogen adsorption measurements were performed on samples that had been annealed at temperatures up to 600°C. Phase transformations and the crystallization of tetragonal PbTiO3 were monitored by X-ray diffraction. While aerogels supercritically dried in carbon dioxide disintegrate upon heat treatment, samples dried in isopropanol can be transformed to the crystalline state as monoliths. With an envelope density of 0.75 g cm-3 these ceramics exhibit a porosity of 90%. © 1998 Chapman & Hall  相似文献   
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Studied 192 middle-class 2nd graders and 192 middle-class 6th graders to test the hypothesis that for young children certain dimensions (e.g., the acoustic) are more likely to be the dominant attributes of a memory than are other dimensions (e.g., the semantic). Data do not replicate the findings of other developmental studies with similar-aged children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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As BiCMOS IC technology continues to advance in scaling and performance, new applications are continually enabled. One such concept is a smart phased array system on a chip (SoC). The combination of high-performance SiGe heterojunction bipolar transistor (HBT) bipolar devices, well-characterized RF/analog passive components, and dense CMOS digital technology provides the capability to create large multielement, electronically tunable phased arrays with onboard processing intelligence, inside a single die. This SoC will have superior characteristics of lower cost, weight, and size as compared to the large multichip, multitechnology, and multipackage systems in deployment today. Furthermore, using reconfigurable logic and embedded memory, this SoC has the advantage of dynamic software and digital signal processing engine updates, without expensive redesigns of the chip. This publication will describe the necessary ingredients to create such an SoC as well as relevant applications of smart phased arrays that require an SiGe HBT BiCMOS technology. Potential markets for this technology include communications systems, weather tracking, radio astronomy, automotive radar, cellular basestation capacity improvement, satellite and aerial resource imaging, ground-level airplane collision avoidance, as well as military tracking and guidance systems.  相似文献   
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Investigated whether performance, for both sexes, is conditioned by expectations for them, with expectations being at least partly defined by same-sex role models. 276 undergraduates were exposed to all-male, all-female, or mixed-authority role models and then participated in a 4-person mixed-sex discussion. Vicarious cultural experience of authority models was represented by videotaped reenactments of TV commercials. Ss viewed either 4 traditional commercials showing a man as authority and woman as subordinate, or 4 reversed-role versions in which the male and female actors switched roles in the same scenarios. Personally observed authority models were represented by the experimenter, who supervised the discussion. Sex of authority in the commercials and sex of experimenter were crossed in a factorial design. In the all-male authority condition, men and women performed equally (as measured by talking time and number of substantive content suggestions), but recognized only the men as leaders in postdiscussion evaluation questionnaires. In the all-female authority condition, men and women also performed equally, and, in addition, they also received equal leadership recognition. In the 2 mixed-authority conditions, men objectively outperformed women. The data show that recognition is not a direct function of performance for either sex but is influenced by the evaluators' expectations, which are partly defined by sex of authority role models in the social environment. (103 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Characterization of the effects of aircraft deicer and anti-icer fluid (ADAF) runoff on aquatic organisms in receiving streams is a complex issue because the identities of numerous toxic additives are proprietary and not publicly available. Most potentially toxic and endocrine disrupting effects caused by ADAF are due to the numerous additive package ingredients which vary among manufacturers and types of ADAF formulation. Toxicity investigations of nine ADAF formulations indicate that endpoint concentrations for formulations of different manufacturers are widely variable. Type IV ADAF (anti-icers) are more toxic than Type I (deicers) for the four organisms tested (Vibrio fischeri, Pimephales promelas, Ceriodaphnia dubia, and Selenastrum capricornutum). Acute toxicity endpoint concentrations ranged from 347 to 7700 mg/L as ADAF for Type IV and from 1550 to 45,100 mg/L for Type I formulations. Chronic endpoint concentrations ranged from 70 to 1300 mg/L for Type IV and from 37 to 18,400 mg/L for Type I formulations. Alkylphenol ethoxylates and tolyltriazoles are two known classes of additives. Nonylphenol, nonylphenol ethoxylates, octylphenol, octylphenol ethoxylates, and 4,5-methyl-1H-benzotriazoles were quantified in the nine ADAF formulations, and toxicity tests were conducted with nonylphenol ethoxylates and 4,5-methyl-1H-benzotriazoles. Toxicity units computed for glycol and these additives, with respect to toxicity of the ADAF formulations, indicate that a portion of ADAF toxicity can be explained by the known additives and glycols, but much of the toxicity is due to unidentified additives.  相似文献   
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