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1.
Analog Integrated Circuits and Signal Processing - This paper presents the complete design of a phase locked loop-based clock synthesizer for reconfigurable analog-to-digital converters. The...  相似文献   
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Personal and Ubiquitous Computing - This article presents a study concerning the evaluation of a smart home control system for elderly people with a sample of 10 users in a city in the interior of...  相似文献   
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The past decade may be regarded as the phase of the fundamental developments in fieldbus systems that were based on the OSI model. Today we are entering a second stage. It is the objective of this issue to present the current state and where the further developments will lead to. This introductory article is intended to give an overview on the subject.  相似文献   
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Platelet aggregation is known to be inhibited by ethanol, and this has been suggested to be one of the attenuating effects of ethanol in cardiovascular disease. Recent studies have implicated an inhibition of phospholipase A2 induced arachidonic acid release, since the production of prostanoids that are formed from arachidonic acid and are involved in the aggregation process has been shown to be diminished by ethanol. Phospholipase A2 is found in platelets in both a cytosolic form, from where it may translocate to the plasma membrane to release arachidonic acid, and in a secretory form which is released extracellularly upon activition. In the present study, the effect of ethanol on the secretion of phospholipase A2 and on its activity was determined. It was found that ethanol inhibited trast, the activity of the cytosolic form of phospholipase A2 was inhibited by ethanol.  相似文献   
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Fault tolerance and self-checking capabilities are key features of modern smart sensors, which often require the integration of additional signal processing facilities. In high-volume production areas such as automotive applications, however, optimized controllers are employed that typically have only limited computing resources. This paper examines several algorithms to assess the noise in a quasi-closed loop measurement channel under the assumption that the stimulus can be held constant during noise measurement. Starting from the definition of standard deviation, we propose several modifications and obtain an easy-to-implement algorithm relying entirely on addition and shift operations. Numerical experiments based on simulated and measured noise verify the practicability of the approach. The proposed algorithm has already been successfully implemented in a capacitive angular speed sensor system for automotive applications.  相似文献   
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The reticular lamina creates an ion barrier, withstands mechanical stress in the organ of Corti and is able to maintain its integrity during and after severe hair cell loss. Tight junctions maintain the ionic gradient whereas adherens junctions and the cytoskeleton are responsible for the integrity and mechanical resistance of tissues. In this study we used immunofluorescence and electron microscopy to examine the distribution of proteins of tight junctions (cingulin), adherens junctions (E-cadherin, alpha- and beta-catenin) and the cytoskeleton (actin, cytokeratin and tubulin) in whole-mounts of the normal and ototoxically damaged organ of Corti. In normal ears the proteins of adherens junctions were found in all cell types of the reticular lamina. We now demonstrate that all cells forming the reticular lamina partially overlap each other organizing extensive cell contacts with a complex three-dimensional shape. During scar formation, the tight junctions as well as adherens junctions between hair and supporting cells appeared in two distinct focal planes, which could help to preserve the ionic barrier and tissue integrity during hair cell degeneration. During scar formation all cytoskeletal structures in the reticular lamina were reorganized in a specific spatio-temporal pattern. We present a three-dimensional model of cell contact organization in the reticular lamina of normal ears and during scar formation.  相似文献   
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Seed kernels ofCalodendrum capense (L.f.) Thunb. yielded 60% of a light yellow oil which had the following fatty acid composition: 23.8% palmitic, 4.5% stearic, 33.7% oleic, 35.6% linoleic, 1.4% linolenic and 1.0% arachidic. Myristic and behenic acids were present in trace amounts, and the kernel cake contained 37.6% crude protein.  相似文献   
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