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71.
Following stroke-like lesions to the sensorimotor cortex in rats, experience with the ipsi-to-lesion (ipsilesional), “nonparetic”, forelimb worsens deficits in the contralesional, “paretic”, forelimb. We tested whether the maladaptive effects of experience with the nonparetic limb are mediated through callosal connections and the contralesional sensorimotor cortex. Adult male rats with proficiency in skilled reaching with their dominant (for reaching) forelimb received ischemic bilateral sensorimotor cortex lesions, or unilateral lesions, with or without callosal transections. After assessing dominant forelimb function (the paretic forelimb in rats with unilateral lesions), animals were trained with their nonparetic/nondominant forelimb or underwent control procedures for 15 days. Animals were then tested with their paretic/dominant forelimb. In animals with unilateral lesions only, nonparetic forelimb training worsened subsequent performance with the paretic forelimb, as found previously. This effect was not found in animals with both callosal transections and unilateral lesions. After bilateral lesions, training the nondominant limb did not worsen function of the dominant limb compared with controls. Thus, the maladaptive effects of training the nonparetic limb on paretic forelimb function depend upon the contralesional cortex and transcallosal projections. This suggests that this experience-dependent disruption of functional recovery is mediated through interhemispheric connections of the sensorimotor cortex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Successful design and implementation of interoperable health IT requires an understanding of specific technological capabilities of systems, as well as how these systems impact clinical workflow. Several existing frameworks classify interoperability levels, but none focus on the impact on clinical work, particularly at the task level. A synthesis of existing interoperability frameworks from select interoperability frameworks in the literature about both medical and non-medical systems is presented and a new, 7-level framework in order to characterise the effect of varying levels of interoperability on the users’ work based upon qualitative data collected in a field study of the use of health information exchange in 12 ambulatory practices is proposed. The lowest level describes paper-based tasks completed with no access to electronic information from other institutions; the highest level describes interoperable systems in which data elements from other institutions are integrated into the patient's record seamlessly and in a computable format.  相似文献   
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An interpenetrating polymer network (IPN) material with controllable nanoporosity is developed for applications such as chemical protection. The IPN material is based on a conducting polymer backbone consisting of thiophene and 3,4 ethylenedioxythiophene (EDOT) repeat units–poly(thiophene‐EDOT)–formed within a soft polyurethane support. The IPN demonstrates reversible, electrochemically switchable nanoporosity in the absence of standard liquid electrolyte, with the oxidized state being the open (high porosity) state and the reduced state being the closed (low porosity) state. The switching of the IPN between its oxidized (open) and reduced (closed) states is actuated using application of ±1.0 V. The variability in the IPN porosity, induced by the electrochemical switching, is revealed by large changes in water vapor diffusivity, as well as changes in the diffusivities of the chemical agent simulants chloroethyl ethyl sulfide (CEES) and methyl salicylate (MeS). The closed state of the IPN is able to decrease CEES diffusivity by ≈99% compared to expanded Teflon (ePTFE), while the open state allows high MVT rates comparable to ePTFE. The IPN's ability to allow high MVT under non‐threat conditions (open state) and high protection from agents under threat conditions (closed state) is a unique and desirable characteristic of this novel IPN material.  相似文献   
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Three general properties of social stereotypes are the perception of differences between ingroups and outgroups (intergroup differentiation), the perception of ingroups as having more desirable attributes than outgroups (ingroup favoritism), and the greater accuracy of ingroup perceptions (differential accuracy). We present and test an inductive-reasoning model that accounts for all 3 phenomena, and we explicate the relations among them. Based on empirical evidence, the model assumes that most people have a positive self-image, that they project these self-images more strongly to ingroups than to outgroups, and that their self-images are valid cues for judgments about social groups. Two minimal-group experiments using a crossed-categorization paradigm support the model and provide new evidence for underlying psychological processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The Seebeck coefficient, S, and the electrical conductivity, σ, of electrodeposited poly(3,4-ethylenedioxythiophene) (PEDOT) nanowires and thin films are reported. PEDOT nanowires were prepared by electropolymerizing 3,4-ethylenedioxythiophene (EDOT) in aqueous LiClO(4) within a template prepared using the lithographically patterned nanowire electrodeposition (LPNE) process. These nanowires were 40-90 nm in thickness, 150-580 nm in width, and 200 μm in length. σ and S were measured from 190 K to 310 K by fabricating heaters and thermocouples on top of arrays of 750 PEDOT nanowires. Such PEDOT nanowire arrays consistently produced S values that were higher than those for PEDOT films: up to -122 μV/K (310 K) for nanowires and up to -57 μV/K (310 K) for films. The sample-to-sample variation in S for 14 samples of PEDOT nanowires and films, across a wide range of critical dimensions, is fully explained by variations in the carrier concentrations in accordance with the Mott equation. In spite of their higher |S| values, PEDOT nanowires also had higher σ than films, on average, because electron mobilities were greater in nanowires by a factor of 3.  相似文献   
79.
Neurotropic viruses target the brain and contribute to neurologic diseases. Caspase recruitment domain containing family member 9 (CARD9) controls protective immunity in a variety of infectious disorders. To investigate the effect of CARD9 in neurotropic virus infection, CARD9−/− and corresponding C57BL/6 wild-type control mice were infected with Theiler’s murine encephalomyelitis virus (TMEV). Brain tissue was analyzed by histology, immunohistochemistry and molecular analyses, and spleens by flow cytometry. To determine the impact of CARD9 deficiency on T cell responses in vitro, antigen presentation assays were utilized. Genetic ablation of CARD9 enhanced early pro-inflammatory cytokine responses and accelerated infiltration of T and B cells in the brain, together with a transient increase in TMEV-infected cells in the hippocampus. CARD9−/− mice showed an increased loss of neuronal nuclear protein+ mature neurons and doublecortin+ neuronal precursor cells and an increase in β-amyloid precursor protein+ damaged axons in the hippocampus. No effect of CARD9 deficiency was found on the initiation of CD8+ T cell responses by flow cytometry and co-culture experiments using virus-exposed dendritic cells or microglia-enriched glial cell mixtures, respectively. The present study indicates that CARD9 is dispensable for the initiation of early antiviral responses and TMEV elimination but may contribute to the modulation of neuroinflammation, thereby reducing hippocampal injury following neurotropic virus infection.  相似文献   
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Abstract  

The conversion of synthesis gas to hydrocarbon fuels by Co catalysts through the Fischer–Tropsch process has received renewed attention particularly with regard to the role of promoters. In this letter, we utilize scanning transmission electron microscopy imaging and electron energy-loss spectroscopy to elucidate the interaction between the Mn promoter, the Co nano-catalysts, and the TiO2 support. In-situ heating experiments show the diffusion of Mn and Ti-support onto the Co particle under reducing conditions.  相似文献   
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