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21.
Siri Simona; Kensinger Elizabeth A.; Cappa Stefano F.; Hood Kristin L.; Corkin Suzanne 《Canadian Metallurgical Quarterly》2003,17(4):630
In this article the authors describe a patient (J.P.) whose category-specific naming deficit eluded the classical dichotomies between living versus nonliving items or visual versus functional attributes. At age 22, he had herpes simplex encephalitis followed by a left temporal lobectomy. J.P. was tested on measures of visual perception, category naming, fluency, and name-picture matching. He showed a severe impairment naming and identifying fruits, vegetables, and musical instruments. His performance with animals and birds was spared inconsistently, meaning that even the preserved categories were, at some point, affected. J.P.'s unusual deficit supports the hypothesis that semantic knowledge is organized in the brain on the basis of object properties, which can cut across the living-nonliving categorical distinction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
High‐Throughput Continuous Flow Production of Nanoscale Liposomes by Microfluidic Vertical Flow Focusing
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Liposomes represent a leading class of nanoparticles for drug delivery. While a variety of techniques for liposome synthesis have been reported that take advantage of microfluidic flow elements to achieve precise control over the size and polydispersity of nanoscale liposomes, with important implications for nanomedicine applications, these methods suffer from extremely limited throughput, making them impractical for large‐scale nanoparticle synthesis. High aspect ratio microfluidic vertical flow focusing is investigated here as a new approach to overcoming the throughput limits of established microfluidic nanoparticle synthesis techniques. Here the vertical flow focusing technique is utilized to generate populations of small, unilamellar, and nearly monodisperse liposomal nanoparticles with exceptionally high production rates and remarkable sample homogeneity. By leveraging this platform, liposomes with modal diameters ranging from 80 to 200 nm are prepared at production rates as high as 1.6 mg min−1 in a simple flow‐through process. 相似文献
23.
C. Ramadas Krishnan Balasubramaniam Avinash Hood Makarand Joshi C.V. Krishnamurthy 《Composite Structures》2011
In this study, the Lamb mode attenuation constants were derived in terms of the attenuation coefficient, group velocity and central frequency of excitation of the Lamb mode, using the Rayleigh damping model. Attenuation of Lamb waves, both fundamental symmetric and anti-symmetric modes, propagating through viscoelastic media (cross-ply glass/epoxy laminate) was modelled using the Finite Element Method. Numerically simulated attenuation of Lamb waves using Lamb mode attenuation constants was found to be in good agreement with the assumed attenuation. Experiments were performed on a quasi-isotropic laminate, employing air-coupled ultrasonic transducers, to measure the attenuation coefficient. Lamb mode attenuation constants, computed using the attenuation coefficient, were used to model the attenuation of the Lamb mode in quasi-isotropic laminates. Numerically simulated amplitude variation was found to be in good agreement with that computed from experiments. 相似文献
24.
In metazoan cells, the CAS protein has been shown to function as a recycling factor for the importin-alpha subunit of the classical nuclear localization signal receptor, exporting importin-alpha from the nucleus to allow its participation in multiple rounds of nuclear import. CAS is a member of a family of proteins that bear homology to the larger subunit of the nuclear localization signal receptor, importin-beta, and that are found in all eukaryotes from yeast to humans. Sequence similarity identifies the product of the Saccharomyces cerevisiae CSE1 gene as a potential CAS homologue. Here we present evidence that Cse1p is the functional homologue of CAS: Cse1p is required to prevent accumulation of Srp1p/importin-alpha in the nucleus, it localizes to the nuclear envelope in a pattern typical of nuclear transport receptors, and it associates in vivo with Srp1p in a nucleotide-specific manner. We show further that mutations in CSE1 and SRP1 have specific effects on their association and on the intracellular localization of Cse1p. 相似文献
25.
Network access systems (NAS) such as digital loop carriers (DLC) are increasingly utilizing a shared medium, such as Hybrid Fiber Coax (HFC) to provide point‐to‐multi‐point access from the public switched telephone network (PSTN) to the end user (consumer). New services, such as direct access to the packet switched network (PSN, WWW) have been added to DLC equipment in such a way as to provide for a prioritized set of services over a shared medium in an effort to take advantage of otherwise unused bandwidth. The introduction of such services requires the modeling and analysis of these network access systems. This becomes complex when considering the variability in different service type traffic characteristics. This work identifies a traffic engineering problem of prioritized circuit switched and packet switched (PSTN/PSN) traffic over the same shared medium as it may relate to “perceived” quality of service (QoS). Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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A Biglan D Ary H Yudelson TE Duncan D Hood L James V Koehn Z Wright C Black D Levings S Smith E Gaiser 《Canadian Metallurgical Quarterly》1996,24(3):311-339
The experimental evaluation of two components of a community intervention to prevent adolescent tobacco use are described. Youth antitobacco activities (e.g., peer quizzes, sidewalk art, poster and T-shirt giveaways, etc.) and family communications activities (pamphlets to parents and student quizzes of parents) were evaluated in two time-series experiments, each of which was conducted in two experimental and one control community. Students in Grades 6 and 8 and their parents were assessed in a series of four phone surveys in the first experiment and six phone surveys in the second. Implementation of the youth antitobacco and family communications activities led to significantly greater exposure of young people to antitobacco information. They led to increases in parent and youth knowledge about tobacco use and more negative attitudes toward tobacco. In Experiment 2, youths in intervention communities had significantly lower rated intentions to smoke. The findings suggest the value of a modular approach to community interventions for influencing the social context relevant to the onset of adolescent tobacco use. 相似文献
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Cairns Robert B.; MacCombie Dennis J.; Hood Kathryn E. 《Canadian Metallurgical Quarterly》1983,97(1):69
In Exp I, stable lines of mice that differed in the frequency and latency of attacks were rapidly established in 2 series (by S? in the 1st series and S? or S? in the 2nd). For evaluation of the developmental-genetic proposal, an analysis was made of the ontogeny of aggressive expression in male mice of the 2 series, with a report provided of the S? and S? generations of the 2nd breeding series (Exps II and III). Comparisons between results of a longitudinal design and results of a new type of cross-sectional design (involving only siblings, or co-sibial) indicated (a) a reliable developmental course of attack expression, with a sharp rise in early maturity and a slow decline thereafter; (b) a convergence in later maturity of the behavior of lines selectively bred for high or low aggressive behavior, if Ss had been assigned to the longitudinal design; (c) a strong effect of repeated testing on attack latency and frequency, even though the dyadic tests were brief in duration and separated by long intervals. In addition, cross-generational comparisons suggested that the selective breeding differences came about primarily by changes in the behavior of the low aggressive lines, in that these Ss failed to show in early maturity the sharp increases in attack occurrence that were observed in earlier generations. Implications for developmental and evolutionary concepts (e.g., neoteny, acceleration, and heterochrony) are discussed. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献