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51.
Presents a model arguing that affect and emotion are often formed in an expectation-driven fashion. A pilot study and 2 experiments manipulated undergraduate Ss' affective expectations (e.g., how funny they expected a set of cartoons to be) and whether Ss' expectations were confirmed (e.g., whether the cartoons really were funny). When the value of a stimulus was consistent with an affective expectation, people formed evaluations relatively quickly. Even when the value of a stimulus was discrepant from an affective expectation, people sometimes assimilated the value of the stimulus to their expectations. Other times, such as when making a more fine-grained evaluation of the cartoons, people noticed that they were discrepant from their affective expectations. Under these conditions, people appeared to have more difficulty forming preferences. They took longer to evaluate and spent more time thinking about the cartoons. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
In helical portal venous blood flow, the usual laminar flow in the portal vein is replaced by a spiral. This changes the color Doppler ultrasound (US) appearance to one of alternating or parallel red and blue bands. Duplex US may appear to show hepatopetal, hepatofugal, or simultaneous bidirectional flow depending on placement of the cursor within the helix. Helical portal venous flow is unusual in normal individuals (2.2% of 135 patients). Its presence should prompt further scrutiny for signs of liver disease, particularly portosystemic shunts, as in 20% of 41 patients who subsequently underwent liver transplantation. It is a normal finding immediately after liver transplantation (43% of 35 patients) and transjugular intrahepatic portosystemic shunt (TIPS) creation (28% of 36 patients). In both liver transplant and TIPS recipients, helical flow is usually transient. Its persistence long after transplantation in association with a prolonged increase in portal venous velocity is a useful sign of portal vein stenosis. Helical flow may also occur in cases of neoplastic invasion or displacement of the portal vein.  相似文献   
53.
54.
We are investigating the role of high performance computing for support of a comprehensive pathology image atlas. The primary computing component is a database access mechanism providing retrieval by content based image matching (CBIR) along with traditional term based queries. An organization based on information theoretic and Bayesian principles using decision trees and signature files is being developed. The essential role of HPC is the discovery, selection, and optimization of medically useful image feature sets via genetic algorithm and simulated annealing methods. This paper outlines the problem area along with aspects of the underlying theoretical basis and distinguishing computing characteristics. Efficiency of key portions of the computations can be greatly improved by using parallelism within the computer word length using bit counting instructions to implement voting and multimedia style instruction sets for low level image processing.  相似文献   
55.
Interleukin 4 (IL-4) is a pleiotropic cytokine. Of the cell types responsive to IL-4, T cells express one IL-4 receptor (IL-4R) type, IL-4Ralpha/IL-2Rgamma (class I IL-4R), whereas endothelial cells express another type, IL-4Ralpha/IL-13Ralpha (class II IL-4R). It was hypothesized that IL-4 variants could be generated that would be selective for cell types expressing the different IL-4Rs. A series of IL-4 muteins were generated that were substituted in the region of IL-4 implicated in interactions with IL-2Rgamma. These muteins were evaluated in T cell and endothelial cell assays. One of these muteins, containing the mutation Arg-121 to Glu (IL-4/R121E), exhibited complete biological selectivity for T cells, B cells, and monocytes, but showed no activity on endothelial cells. Receptor binding studies indicated that IL-4/R121E retained physical interaction with IL-2Rgamma but not IL-13Ralpha; consistent with this observation, IL-4/R121E was an antagonist of IL-4-induced activity on endothelial cells. IL-4/R121E exhibits a spectrum of activities in vitro that suggest utility in the treatment of certain autoimmune diseases.  相似文献   
56.
The status of priming on the general knowledge test was examined in amnesia. Twenty amnesic and 20 control participants studied words (e.g., CHEETAH) under semantic and nonsemantic encoding conditions and attempted to answer general knowledge questions (e.g., "What is the fastest animal on earth"?) under implicit and explicit retrieval instructions. The measure of memory was how many more test questions participants answered correctly using studied than nonstudied words. Amnesic patients showed impaired memory under implicit and explicit retrieval instructions. Control participants showed equal memory under implicit and explicit retrieval instructions, a result indicating that they engaged in explicit retrieval in both instruction conditions. General-knowledge priming appears to involve explicit retrieval that depends on medial-temporal and diencephalic regions damaged in amnesia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
Twin‐screw extrusion processes are commonly refined on laboratory‐scale extruders then scaled‐up to manufacturing systems. When using twin‐screw extrusion to compound filler into a polymer, the dispersion of the filler must be considered during scale‐up. In this work, two scale‐up methods are evaluated for how accurately they scale dispersion as measured by the Residence Stress Distribution, an experimental method that quantifies stress developed in a twin‐screw extruder. The first scale‐up method evaluated is the industry‐standard scaling based on maintaining equivalent volumetric flow rate across extruder sizes. Volumetric scaling is compared to a second, novel scale‐up method, the percent drag flow rule, which maintains the same degree of fill in the strongest dispersive screw elements on all extruder sizes. Both scale‐up rules have been used to scale between three extruder sizes and have been evaluated for how accurately the larger extruders recreate the dispersive mixing of the smallest machine. Results indicate that the percent drag flow scale‐up more accurately maintains dispersive mixing behavior than the volumetric scaling. Furthermore, percent drag flow scale‐up resulted in all three extruder sizes behaving similarly to changes in operating conditions. These results indicate that percent drag flow scale‐up is a valid technique to scale real industrial processes. POLYM. ENG. SCI., 57:345–354, 2017. © 2016 Society of Plastics Engineers  相似文献   
58.
Polymer electrolytes were developed to improve simultaneous demonstration of mechanical and electrochemical properties. Solvent-free random copolymers were synthesized using one monomer with poly(ethylene glycol) sidechains that promote lithium ion conduction and one crosslinking monomer that promotes high modulus. Sixty unique systems of monomer pairs were developed in this manner. The properties of the resulting copolymers were influenced by the monomer ratio and chemistry. The copolymers consistently exhibited improved electrochemical-mechanical multifunctionality with respect to the analogous homopolymers. The most promising systems included highly conductive components paired with highly structural components, suggesting that improved multifunctionality may be achieved through interpenetrating multicomponent systems in which each component demonstrates high efficiency in a single property. Electrochemical, mechanical, and viscoelastic properties are discussed with respect to composition and the glass transition temperature. Modeling of conductivity and modulus was employed to enable prediction of copolymer properties based on the ratio and properties of the constituents.  相似文献   
59.
We investigate the transfer of random nanostructures commonly used in thin film silicon solar cells onto inexpensive substrates, such as glass or flexible polyethylene sheets. Morphological and optical analyses of masters and replicas show the successful transfer of details with sizes much below 1 μm. These high-quality replicas are obtained by UV nano-imprinting, avoiding the use of PDMS as an intermediate mold, which has been identified as being responsible for the lack of resolution found in previous works.  相似文献   
60.
For structures made of carbon fiber-reinforced plastics (CFRP), fast, robust, and reliable repair technologies are mandatory for economical usage. In this paper, the authors explain their strategy and experiences. An automated process is proposed to achieve the challenging goals. A general overview on the origin, effects, and analysis of contaminants in CFRP structures and the relationship to the achievable strength of adhesive bonds are given. For the repair of composite structures using adhesive bonding, surface pretreatment is a key factor in terms of reliability and strength. Different surface treatment processes such as grinding, grit blasting, plasma and pulsed lasers treatments are discussed. Furthermore, the possibilities and technical implementation of an automated milling process for the repair of composite structures are presented. This change from manual production to automation tremendously improved the quality and duration of the repair and allows the creation of a uniform surface for adhesive bonding. Further integration of novel technologies is discussed and will further support and enhance the repair in the near future.  相似文献   
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