Timecourse of object-related neural activity in the primate prefrontal cortex during a short-term memory task

We studied the timecourse of neural activity in the primate (Macacca mulatta) prefrontal (PF) cortex during an object delayed-matching-to-sample (DMS) task. To assess the effects of experience on this timecourse, we conducted the task using both novel and highly familiar objects. In addition, noise patterns containing no task-relevant information were used as samples on some trials. Comparison of average PF ensemble activity relative to baseline activity generated by objects and noise patterns revealed three distinct activity periods. (i) Sample onset elicited a transient sensory visual response. In this sensory period, novel objects elicited stronger average ensemble activity than both familiar objects and noise patterns. (ii) An intermediate period of elevated activity followed, which began before sample offset, and continued well into the delay period. In the intermediate period, activity was elevated for noise patterns and novel objects, but near baseline for familiar objects. (iii) Finally, after average ensemble activity reached baseline activity at the end of the intermediate period, a reactivation period occurred late in the delay. Experience had little effect during reactivation, where activity was elevated for both novel and familiar objects compared to noise patterns. We show that the ensemble average resembles the activity timecourse of many single prefrontal neurons. These results suggest that PF delay activity does not merely maintain recent sensory input, but is subject to more complex experience-dependent dynamics. This has implications for how delay activity is generated and maintained.     

中青年肾移植者服环孢素A后尿酸及肌酐等指标的三维图像

目的：研究中、青年肾移植患者服用环孢素天数、血红蛋白、总胆红素、直接胆红素、尿酸、肌酐、尿素氮的三维图像，使临床指标形象化，为预测疾病提供信息。方法：将40-59岁中年患者（n=219）与小于40岁的青年患者（n=145）的这7个指标分成三组：（血红蛋白＋总胆红素＋直接胆红素）组，（服药天数＋总胆红素＋尿酸）组，（服药天数＋肌酐＋尿素氮）组，采用MATLAB7．0分别作中年、青年组的三维图像，分析图像特征与对中年、青年组图像比较。结果：三维图像显示出各项指标间存在内在关系与个体差异。结论：体内指标与服药天数相关，体内指标对临床预防疾病具有重要意义。     

基于描述的微血管网络图象压缩

微血管网络图象已日渐成为临床诊断和科学研究的重要依据，为了压缩无用数据，保留已有测量结果，本文提出了基于描述的微血管网络图象压缩技术。通过血管提取、细化等步骤，最后建立了相应于原血管图的数学描述结构，这种方法使数据达到了极高的压缩比。借助于生成的描述结构，可以方便地获得已有的测量结果而无需对图象作恢复和再测量。由于描述保留了足够充分的网络构造信息，因此使网络重构成为可能。     

The Poggendorff illusion explained by natural scene geometry

One of the most intriguing of the many discrepancies between perceived spatial relationships and the physical structure of visual stimuli is the Poggendorff illusion, when an obliquely oriented line that is interrupted no longer appears collinear. Although many different theories have been proposed to explain this effect, there has been no consensus about its cause. Here, we use a database of range images (i.e., images that include the distance from the image plane of every pixel in the scene) to show that the probability distribution of the possible locations of line segments across an interval in natural environments can fully account for all of the behavior of this otherwise puzzling phenomenon.     

Unveiling the foveal blue scotoma through an afterimage

The absence of short-wave-sensitive (S-) cones in the human foveola normally goes unnoticed, but the resulting foveal S-cone, or blue, scotoma can be visualized as the negative afterimage of a short-wavelength adapting field on a larger white background. The afterimage has an annular shape with a lighter inner region that corresponds to Maxwell's spot, and a small bright spot in the center corresponding to the foveal blue scotoma. We have shown that the visibility of the center spot in the afterimage approximately follows the spectral sensitivity curve of the S-cones. We further demonstrate that the central bright spot subtends a retinal area that is coincident with the tritanopic region of the foveola. The macular pigment distribution measured for the same observers also peaks in the central fovea, but has a relatively high density over a broader retinal region than the bright spot in the negative afterimage, and more closely corresponds to the lighter annular region of the afterimage. The results support the hypothesis of an active post-receptoral process for filling-in of chromatic scotomas.     

Self-enhancing effects of exposure to thin-body images

OBJECTIVE: This study examines the effect of thin-body media images on mood, self-esteem, and self-image ratings of restrained and unrestrained eaters. A secondary purpose was to examine whether these effects were influenced by exposure duration. METHOD: Under the guise of a perception study, participants were exposed to thin-body or control advertisements (e.g., perfume bottles) for either 7 or 150 ms and then completed a questionnaire packet. RESULTS: Restrained eaters reported more favorable self-image and social self-esteem (but not appearance self-esteem) scores after exposure to thin-body images than after exposure to control advertisements. The self-image and social self-esteem scores of unrestrained eaters were unaffected by advertisement type, but their appearance self-esteem scores were lower after exposure to thin-body advertisements. No differences were found for mood ratings and total self-esteem. DISCUSSION: We discuss restraint status as a moderator of the effects of thin-body images on women's body image.     

Confidential storage and transmission of medical image data

We discuss computationally efficient techniques for confidential storage and transmission of medical image data. Two types of partial encryption techniques based on AES are proposed. The first encrypts a subset of bitplanes of plain image data whereas the second encrypts parts of the JPEG2000 bitstream. We find that encrypting between 20% and 50% of the visual data is sufficient to provide high confidentiality.     

Property analysis of ectopic calcification in the carpal tunnel identification of apatite crystals: a case report

Introduction A 64-year-old woman presented with symptoms of subacute exacerbation of a year-long carpal tunnel syndrome that was caused by a large calcified mass in the tunnel.Conclusion The resected mass consisted of very tiny rods, and x-ray diffraction analysis, as well as the component analysis using energy dispersive x-ray microanalysis, revealed the mass to be most compatible with apatite. The back-scattered electron images suggested that precipitation might be a mechanism for development of the calcified mass.     

FliMax,a novel stimulus device for panoramic and highspeed presentation of behaviourally generated optic flow

A high-speed panoramic visual stimulation device is introduced which is suitable to analyse visual interneurons during stimulation with rapid image displacements as experienced by fast moving animals. The responses of an identified motion sensitive neuron in the visual system of the blowfly to behaviourally generated image sequences are very complex and hard to predict from the established input circuitry of the neuron. This finding suggests that the computational significance of visual interneurons can only be assessed if they are characterised not only by conventional stimuli as are often used for systems analysis, but also by behaviourally relevant input.     

3-D Visualization of Medical Images with Arbitrary Sections

1　ＩＮＴＲＯＤＵＣＴＩＯＮ　　Ｔｈｒｅｅｄｉｍｅｎｓｉｏｎａｌ(3Ｄ)ｖｉｓｕａｌｉｚａｔｉｏｎｏｆｍｅｄｉｃａｌｉｍａｇｅｓ,ｗｈｉｃｈｉｓｆｏｃｕｓｅｄｏｎｔｈｅｄｉｓｐｌａｙａｎｄｉｎｔｅｒｐｒｅｔａｔｉｏｎｏｆａｎａｔｏｍｉｃａｌｓｔｒｕｃｔｕｒｅｓ,ｐｌａｙｓａｎｉｍｐｏｒｔａｎｔｒｏｌｅｉｎｔｈｅｍｅｄｉｃａｌｄｅｖｅｌｏｐｍｅｎｔ.Ｉｔｉｓｎｏｔｏｎｌｙａｐｐｌｉｅｄｔｏａｉｄｄｉａｇｎｏｓｉｓ,ｂｕｔａｌｓｏｔｈｅｋｅｙｔｅｃｈｎｏｌｏｇｙｏｆｍａｎｙｍｏｄｅｒｎｍｅｄｉｃａｌｐｒｏｊ…