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41.
42.
Thomas Stieglitz Martin Schuettler Klaus Peter Koch 《IEEE engineering in medicine and biology magazine》2005,24(5):58-65
In the following article, the technologies to fabricate polyimide-based thin and flexible substrates with monolithically integrated electrode arrays and printed circuit boards (PCB) for hybrid electronic assemblies as well as an assembling technique that connects bare electronic dice with flexible PCBs are presented. The concept of modular, flexible biomedical microsystems as neural prostheses is introduced in general and described in detail in three examples. A cuff electrode with integrated multiplexer circuitry and standard implantable cables represents the combination of microtechnology with precision mechanics; a sieve electrode used as an implant in peripheral nerve regeneration studies demonstrates the next level of integration density but still uses a cable connection; and last, joint effort to fabricate the demonstrator of a vision prosthesis that is completely implantable in the eye with a wireless link for energy supply and data transmission is presented. System design, hybrid assembling technology, and flexible multilayer encapsulation using parylene and silicone rubber are the key components for creating a new generation of neural prostheses for complex and challenging new applications. 相似文献
43.
The dependence of the cetane number of hydrotreated light cycle oil on chemical composition has been investigated. Cetane number was related to hydrogen content and aromaticity. The latter was determined by high performance liquid chromatography and also by carbon-13 n.m.r. spectroscopy. Specific correlations were developed in each case and a regression coefficient of 0.99 and a standard error of 1.25 were obtained for the best case. The usefulness of predicting cetane number from fuel composition is discussed. 相似文献
44.
45.
Jackson T.J. Engman E.T. Le Vine D. Schmugge T.J. Lang R. Wood E. Teng W. 《Geoscience and Remote Sensing, IEEE Transactions on》1994,32(1):201-206
MACHYDR0'90 was an experiment conducted in Pennsylvania in 1990 to study the synergistic use of remote sensors in multitemporal hydrologic studies. As part of this mission the pushbroom microwave radiometer was flown and used to produce brightness temperature maps. Verification studies and vegetation algorithms for mixed land cover areas are described 相似文献
46.
Evaluated the impact of pretreatment depression severity and functional impairment on the response of 2 samples of older depressed adolescents (115 Ss total divided into low-severity groups and high-severity groups) to 2 group cognitive-behavioral treatments. Differences between the 2 active treatments and between active treatment and a waiting-list control condition were expected to be greater in the more severely depressed-impaired group. Improvement for the 2 active treatments in comparison to the control condition was greater in the more severely depressed group in one of the samples but not the other. The prediction that the relative effectiveness of the 2 treatments would be accentuated in the more severely depressed adolescents received no support in either sample. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
48.
Lewinsohn Peter M.; Roberts Robert E.; Seeley John R.; Rohde Paul; Gotlib Ian H.; Hops Hyman 《Canadian Metallurgical Quarterly》1994,103(2):302
In a prospective study of adolescent depression, adolescents (N?=?1,508) were assessed at Time 1 and after 1 yr (Time 2) on psychosocial variables hypothesized to be associated with depression. Most psychosocial variables were associated with current (n?=?45) depression. Formerly depressed adolescents (n?=?217) continued to differ from never depressed controls on many of the psychosocial variables. Many of the depression-related measures also acted as risk factors for future depression (n?=?112), especially past depression, current other mental disorders, past suicide attempt, internalizing behavior problems, and physical symptoms. Young women were more likely to be, to become, and to have been depressed. Controlling for the psychosocial variables eliminated the gender difference for current and future but not for past depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Encompassing such versatile analytical techniques as scanning tunneling microscopy and atomic (or scanning) force microscopy, scanning probe microscopes produce high-resolution three-dimensional images. Because of their power as quantitative tools for three-dimensional surface measurement and analysis, the techniques are being used in materials science and engineering for the study of a variety of advanced materials and for investigations into numerous phenomena, including reaction chemistry, crystallinity, kinetics, equilibrium processes, tribology, and conductivity. 相似文献
50.
Johanna Bakker Peter Bridle Anja Koopman 《Journal of the science of food and agriculture》1992,60(4):471-476
The colour stability of juice and purées made from a mixture of two strawberry varieties, stored at + 20°C or at –20°C under aerobic and anaerobic conditions, was studied. High-performance liquid chromatography and spectrophotometric analysis were used to monitor the changes in colour during storage. Pelargonidin 3-glucoside comprised 80% of the total anthocyanin content. Four other pelargonidin-based peaks were found, being 10.4%, 3.5%, 0.7% and 0.3% of the total and two cyanidin peaks were present, being 3.3% and 0.4% of the total. Clarification before storage caused considerable losses in the initial anthocyanin concentrations. Storage conditions (air versus nitrogen) did not influence the rate of loss of anthocyanins during storage or the formation of polymeric pigments. There were no losses in anthocyanins and no increase in the amount of colour measured at 510 nm due to polymers in samples stored at–20°C. Polymerisation occurred in the samples stored at + 20°C, especially in the clarified samples. 相似文献