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41.
Prepulse inhibition (PPI) refers to a reduction in the startle response to a strong sensory stimulus when this stimulus is preceded by a weaker stimulus--the prepulse. PPI reflects a nonlearned sensorimotor gating mechanism and also shows a robust gender difference, with women exhibiting lower PPI than men. The present study examined the eyeblink startle responses to acoustic stimuli of 59 healthy heterosexual and homosexual men and women. Homosexual women showed significantly masculinized PPI compared with heterosexual women, whereas no difference was observed in PPI between homosexual and heterosexual men. These data provide the first evidence for within-gender differences in basic sensorimotor gating mechanisms and implicate the known neural substrates of PPI in human sexual orientation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The mobility and openness of wireless communication technologies make Mobile Healthcare Systems (mHealth) potentially exposed to a number of potential attacks, which significantly undermines their utility and impedes their widespread deployment. Attackers and criminals, even without knowing the context of the transmitted data, with simple eavesdropping on the wireless links, may benefit a lot from linking activities to the identities of patient’s sensors and medical staff members. These vulnerabilities apply to all tiers of the mHealth system. A new anonymous mutual authentication scheme for three-tier mobile healthcare systems with wearable sensors is proposed in this paper. Our scheme consists of three protocols: Protocol-1 allows the anonymous authentication nodes (mobile users and controller nodes) and the HSP medical server in the third tier, while Protocol-2 realizes the anonymous authentication between mobile users and controller nodes in the second tier, and Protocol-3 achieves the anonymous authentication between controller nodes and the wearable body sensors in the first tier. In the design of our protocols, the variation in the resource constraints of the different nodes in the mHealth system are taken into consideration so that our protocols make a better trade-off among security, efficiency and practicality. The security of our protocols are analyzed through rigorous formal proofs using BAN logic tool and informal discussions of security features, possible attacks and countermeasures. Besides, the efficiency of our protocols are concretely evaluated and compared with related schemes. The comparisons show that our scheme outperforms the previous schemes and provides more complete and integrated anonymous authentication services. Finally, the security of our protocols are evaluated by using the Automated Validation of Internet Security Protocols and Applications and the SPAN animator software. The simulation results show that our scheme is secure and satisfy all the specified privacy and authentication goals. 相似文献
45.
We consider a RAKE receiver for coherent binary orthogonal signaling employing predetection maximal-ratio combining (MRC), in which the tap weights are estimated by adding two matched filtered outputs using the two reference signals. The weight estimation errors here are not independent of the additive channel noise, and therefore do not fit into the Gaussian error model for MRC. Instead of analyzing the distribution of the weight estimation errors, we find the characteristic function of the decision variable, and from it we obtain a formula for the symbol error probability 相似文献
46.
Vandana Kumari Manoj Saxena R.S. Gupta Mridula Gupta 《Microelectronics Reliability》2012,52(8):1610-1612
This paper analyzes the effect of temperature variation on various device architectures i.e. Insulated Shallow Extension Silicon On Nothing (ISESON), ISE and SON MOSFET using ATLAS 3D device simulator for 45 nm gate length. The simulation results obtained with the ATLAS has been validated by comparing it with reported experimental data of SON MOSFET. The simulation results demonstrate that out of three device designs, the ISESON MOSFET is the most suitable device for high speed, low voltage and high temperature applications. The integration of ISE and SON onto the conventional bulk MOSFET leads to the enhancement in analog device performance in terms of device efficiency (gm/Ids), device gain (gm/gd), output resistance (Rout) and early voltage (Vea). 相似文献
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J. A. Ansari Kamakshi Kumari Ashish Singh Anurag Mishra 《Wireless Personal Communications》2013,69(4):1365-1378
In this paper, a comparative study of co-planar gap coupled rectangular and elliptical microstrip patch antenna is presented. It is analyzed by using circuit theory concept. The proposed antennas show ultra wideband operations which depend on dimensions of the patches, gap between them as well as air gap thickness. It is observed that the performance of gap coupled elliptical patch antenna is better than that of rectangular patch antenna while the area of rectangular and elliptical patches is same. The bandwidth of proposed rectangular patch antenna is found to be 50.7 % with average gain of 6.5 dBi while for elliptical patch antenna the bandwidth and gain further improves up to 57.6 % and 9.5 dBi respectively. The theoretical results are in good agreement with the simulated results obtained from IE3D simulation software. 相似文献
48.
Multiplicative speckle noise diminishes the radiometric resolution of the synthetic aperture radar (SAR) images and all the coherent images. Speckle removal adds an extra value to an automated SAR image interpretation and analysis. In this paper, dual-tree complex wavelet-transform-based Bayesian method is proposed for despeckling the SAR images. In each subband, the reflectance and noise of the logarithmically transformed wavelet coefficients are modeled using heavy-tailed Burr and zero-mean Gaussian distributions. The closed-form expression for the shape parameter of Burr distribution is derived by employing the Mellin transform. The resultant complex-free quadratic maximum a posteriori solution with suitable shrinkage function yields despeckled SAR images. Extensive experiments are carried out using real SAR images as well as simulated images. The proposed method performs well in terms of equivalent number of looks with 3.5751 dB improvement in homogeneous region1 of Pipe river SAR image, edge preservation with 0.6158 improvement, peak signal to noise ratio of 51.3305 dB, and mean structural similarity index measure of 0.9397 at 0.05 noise variance for synthetically speckled image in comparison to the existing methods and takes averagely 2.3461 times less computing time. The proposed method provides a computationally efficient better speckle reduction in homogeneous regions while still preserving the edge. 相似文献
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N. Kumari A. Ghosh S. Tewari A. Bhattacharjee 《Materials Science in Semiconductor Processing》2013,16(3):905-914
Tin dioxide (SnO2) powder was prepared by the co-precipitation method using SnCl2 solution as a precursor. The powder was then pelletized and sintered. Structural characterization of the samples with XRD confirmed that all the pellets were of SnO2 having polycrystalline nature with the crystallite size of the order of 90 nm. SEM-EDAX was used to confirm the morphology and composition of the samples. The measurements of electrical properties were carried out in the frequency range of 100 Hz to 100 kHz at various fixed temperatures from 40 °C to 160 °C. The a.c. conductivity and the dielectric constant were found to be dependent on both frequency and temperature. The frequency and temperature dependent conduction properties of SnO2 are found to be in accordance with correlated barrier hoping model. Infrared and visible spectroscopic studies show that a strong vibration band characteristic of the SnO2 stretching mode was present at around 620 cm?1 and the samples exhibited optical transmittance in the visible range. 相似文献
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