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291.
The propensity of various types of home humidifiers to support and disseminate microbial contaminants into indoor air was tested. Reservoir water and air discharged from humidifiers seeded in the laboratory or naturally contaminated in the home were analyzed by standard microbiological methods. Clinically insignificant as well as overt or potentially pathogenic microorganisms were found to colonize the reservoirs of all types of humidifiers, but only cool mist and ultrasonic units readily aerosolized bacteria and endotoxin. Only cool mist units emitted hydrophobic fungal spores. Cool mist units discharged the greatest number of water particles in the inhalabk size range (4–16 μm) while ultrasonic units were more likely to emit respirable-sized water particles (< 0.2–4 μm). Overt pathogens isolated from humidifiers in homes included Legionella and a pathogenic Acanthamoeba. Aerosolizing humidifiers should thus be avoided if frequent, thorough cleaning of the units is not practical.  相似文献   
292.
It is assumed that people seek positive self-regard; that is, they are motivated to possess, enhance, and maintain positive self-views. The cross-cultural generalizability of such motivations was addressed by examining Japanese culture. Anthropological, sociological, and psychological analyses revealed that many elements of Japanese culture are incongruent with such motivations. Moreover, the empirical literature provides scant evidence for a need for positive self-regard among Japanese and indicates that a self-critical focus is more characteristic of Japanese. It is argued that the need for self-regard must be culturally variant because the constructions of self and regard themselves differ across cultures. The need for positive self-regard, as it is currently conceptualized, is not a universal, but rather is rooted in significant aspects of North American culture. Conventional interpretations of positive self-regard are too narrow to encompass the Japanese experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
293.
The "one-bead-one-compound" (OBOC) combinatorial library method synthesizes millions of random compounds such that each bead displays only one compound. Bead libraries are screened, and positive beads are isolated for structure analysis. Peptide substrates and inhibitors of protein kinases, and peptide ligands for cell surface receptors have been identified using this method. A novel encoding strategy for OBOC libraries has been developed to identify peptidomimetic and small-molecule ligands that specifically interact with cellular proteins. These ligands will be tested for their effects on cell signaling and used to construct chemical microarrays for further characterization of ligand-protein interactions.  相似文献   
294.
Software Evolution and Software Evolution Processes   总被引:4,自引:0,他引:4  
Most of the software in regular use in businesses and organisations all over the world cannot be completely specified. It cannot be implemented, once and for all. Both the original implementation and the inevitable subsequent evolution (maintenance) are a continual learning experience driven, inter alia, by feedback from the results of the behaviour under execution of the software, as perceived by various stakeholders, by advances and growth in the user organisations and by adaptation to changes in the external world, both independent and as a result of installation and use of the software. Real world, termed type-E, software is essentially evolutionary in nature. The study of the processes of evolution of such software is of considerable interest, as is that of the domains that co-evolve with the software. After briefly discussing the meaning of the term evolution in the context of software, its technology, the software process and related domains, this paper describes some of the facets of the evolution phenomenon and implications to the evolution process as identified during many years of active interest in the topic.  相似文献   
295.
    
The complete primary structure of the major component myoglobin from the California gray whale, Eschrichtius gibbosus, was determined by specific cleavage of the protein to obtain large peptides for degradation by the automatic sequenator. Cleavage at the two methionine residues of the apomyoglobin with cyanogen bromide and at the three arginine residues of the methyl acetimidated protein with trypsin resulted in three and four easily separable peptides, respectively, which when sequenced accounted for 85% of the primary structure. The remainder of the covalent structure was obtained by further digestion of the central cyanogen bromide peptide with trypsin and S. aureus strain V8 protease. This protein differs from that of the sperm whale, Physeter catodon, at 12 positions, from that of the common porpoise, Phocoena phocoena, and the Black Sea dolphin, Delphinus delphis, at 14 positions, and from that of the Amazon River dolphin, Inia geoffrensis, at 7 positions. All substitutions observed in this sequence fit easily into the tertiary structure of sperm whale myoglobin.  相似文献   
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