Selective attention and distractor frequency in naming performance: Comment on Dhooge and Hartsuiker (2010).

E. Dhooge and R. J. Hartsuiker (2010) reported experiments showing that picture naming takes longer with low- than high-frequency distractor words, replicating M. Miozzo and A. Caramazza (2003). In addition, they showed that this distractor-frequency effect disappears when distractors are masked or preexposed. These findings were taken to refute models like WEAVER++ (A. Roelofs, 2003) in which words are selected by competition. However, Dhooge and Hartsuiker do not take into account that according to this model, picture-word interference taps not only into word production but also into attentional processes. Here, the authors indicate that WEAVER++ contains an attentional mechanism that accounts for the distractor-frequency effect (A. Roelofs, 2005). Moreover, the authors demonstrate that the model accounts for the influence of masking and preexposure, and does so in a simpler way than the response exclusion through self-monitoring account advanced by Dhooge and Hartsuiker. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

抵御侧信道分析的AES双路径掩码方法

为抵御功耗、电磁辐射等侧信道分析攻击,提出一种高级加密标准(AES)双路径掩码方法。采用2条数据路径,将随机数和随机S盒用于掩码操作,使一个加、解密轮次内的所有中间运算结果与AES算法的标准中间结果都不相同,且各中间结果的汉明重量随明文随机变化。实验结果表明,AES算法中间结果的汉明重量与该方法产生的能量特征之间的相关性被完全消除,可抵御各种侧信道分析攻击。     

1,10-二氮杂菲分光光度测定钛合金中铁方法的改进

试样采用氢氟酸溶解,饱和硼酸络合,乙酸-乙酸铵作缓冲溶液控制酸度,三元有机铵盐作混合掩蔽剂,1,10-二氮杂菲分光光度法测定钛合金中铁。成功克服了传统分析方法中因受钒(4mg以上)干扰,显色液需放置隔夜后才能测定的缺陷,大大缩短分析时间,获得较满意的结果。该方法准确度高,分析结果重现性较好。     

一种基于掩盖效应的感知域图像质量评价方法

图像的压缩编码技术及其比特流在信息空间上的传输控制，为图像质量的评价提出了新课题。通过分析人类视觉系统(HVS)的视觉非线性、多通道及掩盖效应等特性，建立起相应的图像视觉处理模型，并将原始图像与降质图像变换到感知域进行误差分析。在处理HVS模型的多通道中，将图像的空间频率按视觉系统的掩盖效应特点，分成5个带分别进行滤波，以模拟人眼对图像的主观质量评价特性。实验结果表明这种模拟多通道的图像感知域评价模型，得到的HVS值能充分反映人类视觉系统的掩盖效应的特点，用于对图像质量的评价该模型通用性好，与主观评价结果高度一致。     

Feature integration across space, time, and orientation.

The perception of a visual target can be strongly influenced by flanking stimuli. In static displays, performance on the target improves when the distance to the flanking elements increases—presumably because feature pooling and integration vanishes with distance. Here, we studied feature integration with dynamic stimuli. We show that features of single elements presented within a continuous motion stream are integrated largely independent of spatial distance (and orientation). Hence, space-based models of feature integration cannot be extended to dynamic stimuli. We suggest that feature integration is guided by perceptual grouping operations that maintain the identity of perceptual objects over space and time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nanosponge-based pediatric-controlled release dry suspension of Gabapentin for reconstitution

Abstract

Context: Gabapentin was selected to formulate oral controlled release dry suspension because of short biological half life of 5–7?h and low bioavailability (60%). Gabapentin is a bitter drug so an attempt was made to mask its taste.

Objective: To formulate and evaluate controlled release dry suspension for reconstitution to increase the bioavailability and to control bitter taste of drug.

Materials and methods: Cyclodextrin based nanosponges were synthesized by previously reported melt method. The nanosponge–drug complexes were characterized by FTIR, DSC and PXRD as well as evaluated for taste and saturation solubility. The complexes were coated on Espheres by a suspension layering technique followed by coating with ethyl cellulose and Eudragit RS-100. A dry powder suspension for reconstitution of the microspheres was formulated and evaluated for taste, redispersibility, in vitro dissolution, sedimentation volume, leaching and pharmacokinetics.

Results and discussion: The complexes showed partial entrapment of drug nanocavities. Significant decrease in solubility (25%) was observed in the complexes than pure drug in different media. The microspheres of nanosponge complexes showed desired controlled release profile for 12?h. Insignificant drug leaching was observed in reconstituted suspension during storage for 7 days at 45?°C/75% RH. Nanosponges effectively masked the taste of Gabapentin and the coating polymers provided controlled release of the drug and enhanced taste masking. The results of in vivo studies showed increase in bioavailability of controlled release suspension by 24.09% as compared to pure drug.

Conclusion: The dry powder suspension loaded with microspheres of nanosponges complexes can be proposed as a suitable controlled release drug delivery for Gabapentin.     

沃溪区低品位地表氧化矿石堆浸提金研究与实践

根据沃溪区低品位地表氧化矿矿石的性质特点,通过小型柱浸试验和堆浸工业试验,采用堆浸-活性炭吸附-解吸电解工艺处理该矿石,工艺中采用隐蔽剂以消除砷、锑矿物对氰化的影响,金回收指标较好,经济效益可观。     

基于掩盖效应的无参考数字图像质量评价

针对数字图像的客观质量评估,从噪声检测的角度,提出了一种基于掩盖效应的无参考图像质量评估方法。首先对Hosaka分块进行了改进,取消了该方法对图像尺寸的限制。通过分块,将图像以不同的频率成分区分开来。然后计算各个子块的噪声。根据图像的污染程度,提出了基于掩盖效应的无参考图像峰值信噪比NPSNR。实验结果表明,该方法具有无参考、运算复杂度低、主客观较一致等特点。     

基于谱减法的改进语音增强方法

语音增强技术是解决噪声污染的一项强有力的预处理技术.谱减法通过处理后的语音中会留下所谓的"音乐噪声",针对这个问题,提出了一种多带谱相减与感觉加权相结合的语音增强方法.对带噪语音进行多带谱相减,并根据人的听觉掩蔽特性,对多带谱相减后的信号进行感觉加权,从而进一步降低背景噪声.在语音失真和噪声抑制之间取得良好的折中,减少语音的听觉失真,有效地抑制"音乐噪声",提高语音的清晰度.