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101.
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
102.
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
103.
104.
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
105.
106.
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
107.
Reviews the research concerning the possible functional roles of the prosodic aspects of infant-directed speech ("baby-talk"), and shows that this style of speaking could have both attentional and affective functions (in addition to linguistic ones). Studies of other speech registers could profit from taking similar approaches and even using similar techniques to those used in infant-directed speech research to tease apart the linguistic, attentional, and affective components of these other speaking styles. Nursing-home register is used to exemplify the importance of examining the social, emotional, and linguistic ramifications of a communication style separately. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
Brefeldin A (BFA) has been reported to cause disassembly of the Golgi. We have used three-dimensional (3-D) high-resolution scanning electron microscopy (HRSEM) to investigate these effects in human skin fibroblast cells. The spontaneous reassembly during prolonged exposure to BFA and some effects of forskolin were observed. A BFA concentration of 5μg/ml caused Golgi complexes to become vesicular, resulting in a progressive decrease in the size of the Golgi. Morphologic changes were visible within 2 min of BFA incubation, and by 30 min no identifiable Golgi could be found. Spontaneous reassembly of the Golgi apparatus upon the removal of the BFA or with continued long-term exposure with BFA could not be confirmed. Preliminary experiments with forskolin were not effective in reversing or inhibiting the effects of BFA in human fibroblast cells grown in culture. This inability for spontaneous reassembly and nonreversal by forskolin may reflect a differential effect of BFA in various cell types. HRSEM has proven to be useful for observing 3-D morphologic effects of BFA in Golgi. 相似文献
109.
Janne Halme Minna Toivola Antti Tolvanen Peter Lund 《Solar Energy Materials & Solar Cells》2006,90(7-8):872-886
Electrochemical impedance spectroscopy was used to determine the effective charge transfer resistances of porous dye-sensitized solar cell counter electrodes prepared by low-temperature spray deposition and compression of conductive carbon and platinized Sb-doped SnO2 powders on indium tin oxide-coated plastic substrates. The charge transfer resistances were 0.5–2 and 8–13 Ω cm2, respectively, when using 3-methoxypropionitrile as the electrolyte solvent. The manufacturing method used lends itself to produce mechanically stable and even-quality electrodes in an easy and fast manner. 相似文献
110.