Image processing in swallowing and speech research

An image processing system for application to studies of the temporal and spatial parameters of movement during swallowing and speech is described. Image sequences from videotape are digitized for computerized manipulation and analysis in an attempt to improve on conventional visual inspection. The system is “interactive” or “event-driven”: after executing a function, the computer waits for guidance from the user who controls the program through keyboard and mouse input, selecting options from menus and responding to prompts. The analyst alters image clarity by the application of filters and heightens contrast through video enhancement. A technique called “remapping” reduces head motion and provides uniform spatial scaling. Animated sequences of images are used, as opposed to frame-by-frame analysis, to preserve temporal context and increase efficiency of measurement. Low cost off-the-shelf personal computer hardware is used along with original software tailored to the application.     

无皂乳液聚合法合成均一性聚苯乙烯微球

研究了聚苯乙烯微球的合成过程中，离子强度、聚合时间对粒径的影响及其稳定性，实验结果表明：适当改变离子强度、聚合时间可以得到不同粒径的聚苯乙烯微球，且粒子稳定性较好。     

血细胞彩色图像的微机自动计数方法探讨

目的　探讨血细胞自动计数的方法。方法　采用微机彩色图像处理技术对血液细胞图像进行图像分割和细胞计数。结果　与人工计数相平行 ,相关系数r =0 .96 1～ 0 .997,P >0 .0 5。结论　该方法可行且计数相对精确、迅速、客观     

MR image segmentation using vector decomposition and probability techniques: A general model and its application to dual-echo images

A general model is developed for segmenting magnetic resonance images using vector decomposition and probabilfty techniques. Each voxel is assigned fractional volumes of q tissues from p differently weighted images (q ≤ p + 1) in the presence of partial-volume mixing, random noise, and other tissues. Compared wtth the eigenimage method, fewer differently weighted images are needed for segmenting the q tissues, and the contrast-to-noise ratio in the calculated fractional volumes is improved. The model can produce com-posrte tissue-type images similar to that of the probability methods, by comparing the fractional volumes assigned to different tissues on each voxel. A three-tissue (p = 2, q = 3) model is illustrated for segmenting three tissues from dual-echo images. M provides statistical analysis to the algebraic method. A three-compartment phantom is segmented for validation. Two clinical examples are presented.     

Cortical Distribution of Eeg Activity for Component Processes During Mental Rotation

Alpha power (8–12 Hz) was monitored over the frontal, temporal, parietal and occipital lobes of the left and right cerebral hemispheres while participants mentally rotated three-dimensional shapes to match a specified target. By comparing the activational patterns generated during three experimental conditions, each designed to systematically isolate the involvement of the various subcomponents comprising this mental rotation task, it was suggested that the right frontal lobe mediates encoding and comparison/decision processes, while the left parietal and the left temporal region appear most involved in the generation of images and their mental rotation. A preliminary model describing the cooperative interaction of these cortical regions during mental rotation tasks is proposed.     

Pixel value modification using RVG-4 automatic exposure compensation for instant high-contrast images

The RVG-4 permits automatic exposure compensation (AEC). The purpose of this investigation was to determine the effects of AEC on image contrast. Images were made either with or without a dental QA jaw phantom using a fixed image projection geometry. Exposures were 6.3 through 27.3 μC/kg using an X-ray generator operated at 70 kVp. Region of interest pixel value distributions were measured at tissue thicknesses in this phantom, and the average pixel values and signal-to-noise ratios (SNR) were calculated. The use of AEC without an object in place resulted in a disproportionate relationship between pixel value and exposure with a marked reduction in SNR. The use of AEC on under- and over-exposed images of the phantom simultaneously enhanced image contrast and reduced SNR. Thus, AEC provides a convenient and quick method for achieving high-contrast images with sub-optimal exposures, however, this could lead to inappropriate patient dosages if the function is used for over-exposed images. AEC reduces the SNR and produces disproportionate pixel values relative to exposure.     

Effects of AETT-Induced Neuronal Ceroid Lipofuscinosis on Learning Ability in Rats

Abstract: The behavioral effects of ceroid-lipofuscin accumulation, induced by intraperitoneal administration of acetyl-ethyl-tetramethyl-tetralin (AETT) in Wistar rats for 3 months, were examined in the present studies. A significant increase in neuronal ceroid-lipofuscin was demonstrated neuropathologically as well as morphometrically. Although the AETT-intoxicated rats showed neither alteration of locomotor activity nor shock sensitivity, a significant impairment of learning ability, especially an acquisition trial in passive avoidance tests, was observed. Results of the present studies indicate the possibility that a diffuse lipofuscin accumulation causes a learning impairment in rats. The results also imply the possibility of a significant role of age-related lipofuscin accumulation in the dementing processes of human especially in the elderly.     

眼动脉彩色多普勒血流频谱检测在甲亢诊断中的应用

采用ＣＤＦＩ对３４例初诊甲亢患者的眼动脉进行检测，３４例患者根据Ｔ３结果分为两组，同时１０位患者治疗前后的眼动脉血流速度对照。结果表明，甲亢患者的眼动脉血流速度高于正常人，但与Ｔ３值无相关。１０例患者的眼动脉血流速度随着Ｔ３、Ｔ４下降而恢复正常。结论：ＣＤＦＩ测定眼动脉血流频谱可用于甲亢的诊断和治疗观察。