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381.
Electroconvulsive therapy (ECT) has been successfully used in the treatment of depression, particularly when the illness is refractory to pharmacological therapy. A recent study has shown that ECT is also effective in reducing both depressive and posttraumatic stress disorder (PTSD) symptoms in patients with major depression (MDD) and co-occurring PTSD. This raises the possibility that ECT might be effective in the treatment of PTSD, a disease whose prevalence has increased substantially in recent years. A characteristic symptom of PTSD is an exaggerated reactivity to startling sounds (acoustic startle response; ASR). In the present study, we investigated the effects of electroconvulsive shocks (ECS) on the ASR, in a rat model of traumatic stress. The animals were subjected to a restraint/tailshock paradigm and then administered ECS. ASR measurements were obtained at several time points following ECS administration. Although ECS had no effect in control rats, it significantly exacerbated the already potentiated ASR in the stressed group. While ECT may prove to be an effective treatment for certain symptoms of co-occurring MDD/PTSD or PTSD alone, it may exacerbate heightened arousal associated with PTSD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
382.
Existing works on Wiener system identification have essentially been focused on the case where the output nonlinearity is memoryless. When memory nonlinearities have been considered, the focus has been restricted to backlash like nonlinearities. In this paper, we are considering Wiener systems where the output nonlinearity is a general hysteresis operator captured by the well‐known Bouc–Wen model. The Wiener system identification problem is addressed by making use of a steady‐state property, obtained in periodic regime, referred to as ‘hysteretic loop assumption’. The complexity of this problem comes from the system nonlinearity as well as its unknown parameters that enter in a non‐affine way in the model. It is shown that the linear part of the system is accurately identified using a frequency method. Then, the nonlinear hysteretic subsystem is identified, on the basis of a parameterized representation, using a prediction‐error approach. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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384.
The advances of localization‐enabled technologies have led to huge volumes of large‐scale human mobility data collected from Call Data Records (CDR), Global Positioning System (GPS) tracking systems, and Location Based Social networks (LBSN). These location data that encompass mobility patterns could generate an important value for building accurate and realistic mobility models and hence important value for fields of application including context‐aware advertising, city‐wide sensing applications, urban planning, and more. In this paper, we investigate the underlying spatio‐temporal and structural properties for human mobility patterns, and propose the Community and Geography Aware Mobility (CGAM) model, which characterizes user mobility knowledge through several properties such as home location distribution, community members' distribution, and radius of gyration. We validate the CGAM synthetic traces against real‐world GPS traces and against the traces generated by the baseline mobility model SMOOTH and assess that CGAM is accurate in predicting the performance of flooding‐based and community‐based routing protocols.  相似文献   
385.
In this paper, the dynamic observer-based controller design for a class of neutral systems with H∞ control is considered. An observer-based output feedback is derived for systems with polytopic parameter uncertainties. This controller assures delay-dependent stabilization and H∞ norm bound attenuation from the disturbance input to the controlled output. Numerical examples are provided for illustration and comparison of the proposed conditions.  相似文献   
386.
Wireless Personal Communications - Information retrieval (IR) defines the process of searching and attaining specific information resources which are related to the specific information...  相似文献   
387.

Vehicular Ad hoc Networks (VANETs) have drawn incredible interest in both academic and industrial sectors due to their potential applications and services. Vehicles’ position plays a significant role in many location-based applications and services such as public emergency, vehicles tracking, resource discovery, traffic monitoring and position-based routing. A location service is used to keep up-to-date records of current positions of vehicles. However, locating vehicles’ positions and maintaining an accurate view of the entire network are quite challenging tasks due to the high number of nodes, and high and fast nodes mobility which results in rapid topological changes and sudden network disconnections. In the past literature, various location-based services have been proposed to solve the above mentioned issues. Moreover, the cluster-based location service schemes have gained a growing interest due to their advantages over non-cluster-based schemes. The cluster-based schemes improve the network scalability, reduce the communications overhead and resolve the mobility issues within the clusters preventing them from propagating in the whole network. Therefore, this paper presents the taxonomy of the existing location service schemes, inspects the cluster-based location service by highlighting their strengths and limitations, and provides a comparison between location-based clustering and application specific clustering such as the one used in routing, information dissemination, channel access management and security. In addition, the existing clustering schemes, challenges and future directions for efficient cluster-based location service are also discussed.

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388.
Wireless Personal Communications - Recently, wireless sensor networks (WSNs) attracted the attention of searchers, due to the critical role in several applications like environmental monitoring,...  相似文献   
389.
Advanced organic laser dyes exhibiting high solubility and bipolar behavior are developed based on a structure combining bis‐stilbene with carbazole (BSBCz). The materials show high photoluminescence quantum yields and large radiative rate constants in solutions, crystals, and blend and neat films. The introduction of alkyl groups significantly improves the solubility of BSBCz, and solution‐processed films of the alkyl‐substituted derivatives exhibit amplified spontaneous emission thresholds as low as 0.59 µJ cm?2, which is comparable to those of vacuum‐deposited BSBCz films. On the other hand, cyano‐substitution on BSBCz (BSBCz‐CN) increases electron‐accepting properties, resulting in a bathochromic shift of the emission wavelength and improved bipolar behavior. In a BSBCz‐CN‐doped film, a low ASE threshold of 0.63 µJ cm?2 is achieved, which is one of the lowest values for organic laser dyes with green emission. In addition, organic light‐emitting diodes based on BSBCz‐CN neat films exhibit external quantum efficiencies of 1.8% and could withstand injection of high current densities of up to 500 A cm?2 under pulse operation. These properties along with low excited‐state absorption cross sections make these materials an outstanding addition to the existing library of organic laser dyes, especially for consideration in electrically pumped lasers.  相似文献   
390.
A New Degradation Mechanism in High-Voltage SiC Power MOSFETs   总被引:1,自引:0,他引:1  
The phenomenon of recombination-induced stacking faults in high-voltage p-n diodes in SiC has been previously shown to increase the forward voltage drop due to reduction of minority carrier lifetime. In this paper, it has been shown that, for the first time, this effect is equally important in unipolar devices such as high-voltage MOSFETs. If the internal body diode is allowed to be forward biased during the operation of these devices, then the recombination-induced SFs will reduce the majority carrier conduction current and increase the leakage current in blocking mode. The effect is more noticeable in high-voltage devices where the drift layer is thick and is not expected to impact 600-1200-V devices.  相似文献   
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