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91.
    
Speech perception and memory for speech require active engagement. Gestural theories have emphasized mainly the effect of speaker''s movements on speech perception. They fail to address the effects of listener movement, focusing on communication as a boundary condition constraining movement among interlocutors. The present work attempts to break new ground by using multifractal geometry of physical movement as a common currency for supporting both sides of the speaker–listener dyads. Participants self-paced their listening to a narrative, after which they completed a test of memory querying their narrative comprehension and their ability to recognize words from the story. The multifractal evidence of nonlinear interactions across timescales predicted the fluency of speech perception. Self-pacing movements that enabled listeners to control the presentation of speech sounds constituted a rich exploratory process. The multifractal nonlinearity of this exploration supported several aspects of memory for the perceived spoken language. These findings extend the role of multifractal geometry in the speaker''s movements to the narrative case of speech perception. In addition to posing novel basic research questions, these findings make a compelling case for calibrating multifractal structure in text-to-speech synthesizers for better perception and memory of speech.  相似文献   
92.
Three symbols of terror are examined as representations of preoedipal conflicts that intrude upon conscious awareness and. interfere with current functioning. To understand each of these symbols and their origins in a state of chronic terror, it is necessary to understand the complete life history of the patient. All three symbols--the witch/vampire, the spider, and the shark--relate to earliest experiences within the parent/infant dyad. We suggest that although all three symbols relate to the dimension of oral aggression, they can be placed conceptually along a continuum of distance from the quality of humanness. Clinical examples are given to illustrate the use of these symbols by patients in treatment and their theoretical implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
Theoretical questions of the spatial organization of electrical activity in the brain are discussed in terms of a multilevel realization of the synergetic principle for formation of functional systems underlying behavior and mental function. The role of the spatial-temporal superimposition of coherent structures of biopotentials in generating fields of increased activity in the cerebral cortex is discussed, these being responsible for integrative and associative functions. A hypothesis is proposed regarding the relationship between the energy and information factors of coherent structures as one of the important characteristics describing the efficiency of energy-informational processes. Emphasis is placed on the need for considering not only linear, but also nonlinear associations of biopotentials in considerations of the form and functional sense of their spatial organization.  相似文献   
94.
An exploration of the adoption of E-auctions in supply management   总被引:3,自引:0,他引:3  
Increasingly, reverse e-auctions are replacing traditional competitive bidding for sourcing decisions. Using the Internet, reverse e-auctions allow suppliers to compete dynamically, in real-time, for a buyer's business. During a reverse e-auction, suppliers submit multiple electronic bids over a fixed time period, often 30 min or less. Typically, the price of the item or service being purchased drops, often dramatically, during the bidding process. E-auctions offer a range of benefits to buying organizations including lower transaction costs, shorter order-cycle times, a large pool of potential suppliers, and competitive purchase prices. Some buyers are concerned that the emphasis on price will overshadow other important performance characteristics. The differences between buying organizations that have adopted reverse e-auctions and those that have not used e-auctions for sourcing decisions are explored in this paper. Data for the study were gathered using a survey of vice presidents and directors of purchasing. Chi-squared analysis shows that there are no differences between reverse e-auction adopters and nonadopters on the level of importance placed on the purchasing objectives of cost management and on supplier collaboration. There is a significant difference considering organization size, where reverse e-auction adopters have higher annual sales than nonadopters. The findings suggest that contrary to expectations, e-auction use and supplier collaboration are not mutually exclusive. Opportunities for future research are discussed.  相似文献   
95.
The parallel-plate test fixture on a Rheometrics viscometer was electrically isolated so that the rheological and dielectric properties of a thermoset polymer system could be simultaneously measured. This enabled the relationship between the dielectric properties and the rheological properties to be directly examined. A close relationship was established between the dielectric properties (dipole relaxation time and specific conductivity) and the pre-gelation bulk viscosity. This relationship suggested that models similar in form to those used to describe the change in viscosity might be used to describe the changing dielectric properties. The limitations and advantages of two such models, which attempt to describe the time-temperature behavior of the dielectric properties, were then tested for use with a typical aerospace epoxy resin system.  相似文献   
96.
97.
Blepharitis patients have a number of disturbances in their tear film associated with meibomian gland dysfunction that affect evaporation and tear osmolarity. We tested a series of 156 consecutive patients, with a presumed diagnosis of blepharitis, dry eye, or allergic disease, and a series of 72 normals. We compared their tear film characteristics using tear osmolarity, tear volume, tear production (fluorophotometric and Schirmer test), tear turnover (decay constant), tear evaporation, and meibomian gland function evaluated by gland drop-out, expressed lipid viscosity, and volume. Of the 156 patients tested, we found 37 had dry eye, 10 had only allergic disease, 73 had meibomian gland dysfunction and dry eye, and 36 had only meibomian gland dysfunction. We created a model of the relative influence some of these factors had on each other using their correlation coefficients. The highest correlations for osmolarity were Schirmer test (-0.44), lipid volume low (-0.44), lipid viscosity high (0.39), gland drop-out (0.39), and tear evaporation (0.36). With regression analysis we accounted for 47% of the total variation in osmolarity, but only 17% of the variation in tear evaporation. We also present our classification system for blepharitis and dry eye patients based on our measurable physiologic parameters.  相似文献   
98.
99.
Intraocular infection with herpes simplex virus type I strain F (HSV-1) induces bilateral retinitis, the expression of both MHC class I and II molecules and activation of CD4 and CD8 cells. To investigate the role of MHC upregulation in IFN-gamma mediated antiviral effects in intraocular infection with HSV-1, we infected MHC deficient mice and mice with an additional ectopic site of IFN-gamma production in their retina (rho gamma) intravitreally with HSV-1 into one eye. Protective effects of IFN-gamma in intraocular HSV-1 infection were notable as sparing of the contralateral non-inoculated eye from retinitis, and were not dependent on MHC class I and class II expression, thus limiting the importance of MHC expression for the outcome of viral infection in vivo.  相似文献   
100.
The carboxyl-terminal amino acid sequence serine-lysine-leucine (SKL) is the consensus peroxisomal targeting sequence 1 (PTS1) and is sufficient to direct a polypeptide to peroxisomes in vivo in plants, animals, and yeasts. However, there are also two sites on alkali-stripped glyoxysomal membranes from castor bean (Ricinus communis) endosperm that bind the peptide YHKHLKPLQSKL (SKLp), the sequence of the last 12 amino acids of acyl-coenzyme A oxidase (N.E. Wollins, R.P. Donaldson [1994] J Biol Chem 289: 1149-1153). It was hypothesized that one of these sites interacts with information other than the PTS1. To explore the sequence requirements for each SKLp binding site, we tested the peptides YHKHLKPQSKG and YHKHLKPLQS and found that they bound to the high-affinity site, but not to the low-affinity site. When the high-affinity site was blocked with YHKHLKPQSKG, SKLp bound to the low-affinity site with a dissociation constant (Kd) of 8.5 microM. In an attempt to disrupt high-affinity binding, two the upstream, positively charged residues were replaced with negatively charged residues to make the peptide YHKETEPLQSKL. YHKETEPLQSKL did not bind to either site on the glyoxysomal membranes. These results indicate that the PTS1 binds to the low-affinity site and that the adjacent, positively charged domain binds to the high-affinity site.  相似文献   
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