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41.
We investigated the alterations of hippocampal and reticulo-thalamic (RT) GABAergic parvalbumin (PV) interneurons and their synaptic re-organizations underlying the prodromal local sleep disorders in the distinct rat models of Parkinson’s disease (PD). We demonstrated for the first time that REM sleep is a predisposing state for the high-voltage sleep spindles (HVS) induction in all experimental models of PD, particularly during hippocampal REM sleep in the hemiparkinsonian models. There were the opposite underlying alterations of the hippocampal and RT GABAergic PV+ interneurons along with the distinct MAP2 and PSD-95 expressions. Whereas the PD cholinopathy enhanced the number of PV+ interneurons and suppressed the MAP2/PSD-95 expression, the hemiparkinsonism with PD cholinopathy reduced the number of PV+ interneurons and enhanced the MAP2/PSD-95 expression in the hippocampus. Whereas the PD cholinopathy did not alter PV+ interneurons but partially enhanced MAP2 and suppressed PSD-95 expression remotely in the RT, the hemiparkinsonism with PD cholinopathy reduced the PV+ interneurons, enhanced MAP2, and did not change PSD-95 expression remotely in the RT. Our study demonstrates for the first time an important regulatory role of the hippocampal and RT GABAergic PV+ interneurons and the synaptic protein dynamic alterations in the distinct rat models of PD neuropathology.  相似文献   
42.
Iron chalcogenide superconductors have become one of the most investigated superconducting materials in recent years due to high upper critical fields, competing interactions and complex electronic and magnetic phase diagrams. The structural complexity, defects and atomic site occupancies significantly affect the normal and superconducting states in these compounds. In this work we review the vortex behavior, critical current density and high magnetic field pair-breaking mechanism in iron chalcogenide superconductors. We also point to relevant structural features and normal-state properties.  相似文献   
43.
Does the application of robotic technologies in Southeast Asian cities, where the residential high-rise is pre-eminent, provide a unique opportunity to introduce bespoke design elements and liberate the high-rise from serial production and standardisation? Michael Budig, Jason Lim and Raffael Petrovic of the Future Cities Laboratory (FCL) at the Singapore-ETH Centre for Global Environmental Sustainability (SEC) introduce the research project ‘Design of Robotic Fabricated High Rises’ (2012-13) led by Fabio Gramazio and Matthias Kohler, exploring high-rise typologies and architectural scenarios for future vertical cities.  相似文献   
44.
In this paper an approach to the performance analysis of signal-to-interference (SIR) based selection combining (SC) operating over the Rayleigh fading channels experiencing an arbitrary number of multiple, Rayleigh co-channel interferers is presented. We have presented a general analysis of multibranch SC where each branch experiences an arbitrary number of multiple equal power co-channel interferers. Useful closed form expressions are derived for the probability density function (PDF) and cumulative distribution function (CDF) at the output of the combiner. Also an outage analysis is performed in order to show the effects of the number of multiple interferers, diversity order and input SIR unbalance to the system performances.  相似文献   
45.
Both HCFC‐ and pentane‐blown rigid polyurethane foams have been prepared from polyols derived from soybean oil. The effect of formulation variables on foam properties was studied by altering the types and amounts of catalyst, surfactant, water, crosslinker, blowing agent, and isocyanate, respectively. While compressive strength of the soy foams is optimal at 2 pph of surfactant B‐8404, it increases with increasing the amount of water, glycerin, and isocyanate. It also increases linearly with foam density. These foams were found to have comparable mechanical and thermoinsulating properties to foams of petrochemical origin. A comparison in the thermal and thermo‐oxidative behaviors of soy‐ and PPO‐based foams revealed that the former is more stable toward both thermal degradation and thermal oxidation. The lack of ether linkages in the soy‐based rather than in PPO‐based polyols is thought to be the origin of improved thermal and thermo‐oxidative stabilities of soy‐based foams. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 467–473, 2000  相似文献   
46.
Weibull statistical fracture theory for the fracture of ceramics   总被引:1,自引:0,他引:1  
The Weibull statistical fracture theory is widely applied to the fracture of ceramic materials. The foundations of the Weibull theory for brittle fracture are reviewed. This theory predicts that brittle fracture strength is a function of size, stress distribution, and stress state. Experimental multiaxial loading results for A12O3 tubes are compared to the stress state predictions of the Weibull theory. For the most part, the Weibull theory yields reasonable predictions, although there may be some difficulties in dealing with shear stress effects on fracture. This paper is based on a presentation made at the symposium “Stochastic Aspects of Fracture” held at the 1986 annual AIME meeting in New Orleans, LA, on March 2-6, 1986, under the auspices of the ASM/MSD Flow and Fracture Committee.  相似文献   
47.
The authors present an improved modification of the upper bound on error probability of the canonical binary system with additive interference and Gaussian noise. The proposed modification is illustrated by a sinusoidal interference example. It is shown that in this case, for a signal-to-noise ratio of 0 dB and signal-to-interference ratio of 3 dB, the modified upper bound is 9% larger than the exact value, which is approximately 8.5 times smaller than the error resulting from the Prabhu upper bound on error probability.<>  相似文献   
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Although we have recently seen an increase of good, free game engine editors, general purpose scenario (level) editors are still lagging behind in terms of functionalities and ease of use. Using them to create game scenarios can be difficult as they often expose general engine capabilities instead of limiting the toolset to fit game-specific requirements. They often require programming skills to use, which introduce additional user skill requirements, and configuring them for a specific game can be equally difficult. In this paper we have developed SpringBoard, an open source scenario editor for games using the SpringRTS engine. Extending it to support game and level requirements is achieved with multi-level meta-programming, while still providing a system that is integrated with the GUI editor and therefore intuitive to use. Our meta-programming system has support for trigger elements (events, functions and actions), custom (composite) data types, scoped data access, higher order functions and actions, and data synchronization mechanics. This novel approach allows us to have the full expressiveness of the underlying programming language, while exposing a user-friendly GUI that consists of terminology familiar to the domain expert.  相似文献   
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