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41.
我曾为需要能够在整个家庭输送高清电视流的低成本联网技术这个问题所困扰.我仍然相信视频联网应用将为从集成电路供应商到服务提供商以及信息拥有者带来巨大收益.  相似文献   
42.
The incidence of renal disease is gradually increasing worldwide, and this condition has become a major public health problem because it is a trigger for many other chronic diseases. Cell therapies using multipotent mesenchymal stromal cells, hematopoietic stem cells, macrophages, and other cell types have been used to induce regeneration and provide a cure for acute and chronic kidney disease in experimental models. This review describes the advances in cell therapy protocols applied to acute and chronic kidney injuries and the attempts to apply these treatments in a clinical setting.  相似文献   
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Dispersion fiber sensitivity in optical microwave upconversion links is investigated. Simulations are carried out to calculate output optical spectra and to evaluate mixing power as a function of fiber length for different upconversion systems using dual drive/standard Mach-Zehnder modulators or an unbalanced Mach-Zehnder interferometer (UMZ). The latter solution prevents complete cancellation of mixing power because of the asymmetric double sideband optical spectrum detected at the output of the UMZ. It is shown that an optimum value of the linewidth enhancement factor of the laser diode can be found to minimize degradations of the mixing power along the fiber.  相似文献   
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Maury Wright 《电子设计技术》2008,15(4):50-52,54,56
设计者采用能感知调制方法的测试工具推进下一代无线系统的开发,尽管新兴标准引入了一些PHY层和数据层的问题。  相似文献   
47.
The nutrient contents as well as the amino acid pattern of kishk samples were determined. The level of most of the amino acids were also estimated. High figures for digestibility, biological value and net protein utilisation of kishk were obtained. The use of kishk in school feeding programmes and in military canteens as a high protein food is discussed.  相似文献   
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There is a great variability in cooking time and final texture among cassava cultivars and one factor in determining these characteristics is the age of roots at harvest. Final texture after cooking is an important attribute for the acceptability of cassava and starch gelatinization has a role in softening the tissue. Two cassava cultivars at two different harvest maturities were cooked at 90 °C and at boiling water temperature (98 °C) and the extent of gelatinization was determined using an iodine colorimetric method. A generalized model for starch gelatinization, considering temperature and cooking time as continuous variables and age at harvest as qualitative variable, was used to model the cooking process and applied for each cultivar. At 90 °C IAPAR-19 Pioneira reached maximum gelatinization in 32 min for the 12 month old sample and 88 min for the 25 month old sample, while double the time was needed for Catarina Amarela. At 98 °C Pioneira gelatinized in 12 min for the 12 month and 32 min for the 25 month old sample while Catarina Amarela needed 28 and 56 min. Calculated activation energy for starch gelatinization was 122.3±5.2 and 98.6±4.7 kJ/mol for cultivar IAPAR-19 Pioneira and Catarina Amarela, respectively.  相似文献   
50.
Based on industrial vinegar production, ethanol concentration in charging medium is normally considered as a strong variable influencing the acetification for a given initial acetic acid concentration. Moreover, high initial acetic acid concentration is considered when higher than 100 g L−1 of acetic acid as finished product is obtained. This study assessed the effect of a stepwise increment of initial acetic acid concentration in fermentation medium of 45, 55, and 65 g L−1 after charging at constant ethanol concentration of 35 g L−1 on acetification rate (ETA) by high acid-tolerant strain of Acetobacter aceti WK. Average ETA was 8.144 + 0.09 g L−1 d−1 at 45 g L−1 and 8.655 + 0.09 g L−1 d−1 at 55 g L−1, and significant decreased to 6.819 + 0.23 g L−1 d−1 at 65 g L−1. An artificial neural network (ANN) model was applied to predict the ETA in semi-continuous acetification under the conditions of the study. The optimized ANN structure was revealed to contain two hidden layers and seven neurons per layer. The experimental acetification correlated to the predicted data with R2 of training and testing data set of 0.858 and validation data set of 0.831, respectively. Results indicated that the inputs as acetic acid and ethanol concentrations successfully predicted the ETA of semi-continuous acetification process.  相似文献   
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