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51.
Covalent complexes of nucleic acids and proteins are widespread among viruses. Covalent complexes of RNA and proteins are proposed to exist in eukaryotic cells. The goal of this work was to obtain specific antibodies to the covalent linkage unit (CLU) between virus RNA and protein to search cellular RNA-protein complexes. Antibodies were generated by direct immunization of a rabbit with the BSA-coupled EMC virus RNA-VPg complex. By a dot-blot immunoassay and immunofluorescent microscopy it was found that the antibodies specifically recognize both EMC virus RNA-VPg and synthetic CLU-containing compounds. Thus, a fraction of the antibodies was directed to CLU.  相似文献   
52.
采用轮毂电机独立驱动的电动汽车可采用直接横摆力矩控制(Direct Yaw-moment Control,DYC)等稳定性控制,而车体侧偏角(简称β角)是稳定性控制中的重要参数.直接测定车体侧偏角的传感器相当昂贵,所以需要从能够容易测得的参数来进行车体侧偏角的推测.Hori研究室设计了一种用于β角推测的观测器,并充分考虑了车辆运行工况变化所引起的系统模型参数变化,进行了观测器鲁棒性设计以及轮胎侧偏刚度在线辨识,使观测器具备了足够的鲁棒性来克服大的模型误差影响,试验结果证明了该观测器的有效性.  相似文献   
53.
Hydroxyapatite and Cl -containing hydroxyapatite powders are prepared and characterized. Reversible substitution of CO2-3 for OH at the surface is presumed to be responsible for the sensor function. The role of Cl, which is necessary to realize the sensor function and is incorporated during soaking treatment, is considered as follows. It may reduce the strain caused by the incorporation of CO2-3 (which is larger than OH), and, hence, promote the reversible substitution reaction. This behavior is presumed because Cl -containing hydroxyapatite samples exhibit sensor characteristics typical of CO2 without any treatment.  相似文献   
54.
K. Tanaka  H. Kawaura  N. Matsumoto  K. Nishino   《Calphad》2006,30(4):415-420
A new heat-resistant Fe-based cast alloy has been designed making the best use of the CALPHAD method. The objective was to replace the material for precision cast products made from Ni-based superalloys with improved Fe-based alloys originally developed for lower temperature applications.The key to the design is to balance the amount of strengthening γ- Ni3(Ti,Al) precipitates and brittle σ phase, and to simultaneously decrease as-cast microsegregation. Contours of the equal phase fraction were calculated over the isothermal diagrams of the Fe–Ni–Cr–Ti–Al–Nb system, and provided useful guidelines for compositional modifications. The microsegregation was also evaluated by Scheil-type simulation in order to reduce micropores caused by oxidation of the solidifying front.The developed cast Fe-based alloy showed desirable strength at the envisioned service temperatures and filled the open range of heat resistance between Ni-based superalloys and the original alloy.  相似文献   
55.
In this paper, we propose a method for pose-invariant facial expression recognition from monocular video sequences. The advantage of our method is that, unlike existing methods, our method uses a simple model, called the variable-intensity template, for describing different facial expressions. This makes it possible to prepare a model for each person with very little time and effort. Variable-intensity templates describe how the intensities of multiple points, defined in the vicinity of facial parts, vary with different facial expressions. By using this model in the framework of a particle filter, our method is capable of estimating facial poses and expressions simultaneously. Experiments demonstrate the effectiveness of our method. A recognition rate of over 90% is achieved for all facial orientations, horizontal, vertical, and in-plane, in the range of ±40 degrees, ±20 degrees, and ±40 degrees from the frontal view, respectively. Electronic Supplementary Material  The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   
56.
Novel motion control techniques for electric vehicles (EVs) on the basis of the quick torque generation in these vehicles have been developed at the Hori Laboratory. Because EVs are powered by electric motors, they have three major advantages: (i) motor torque generation is quick and accurate, (ii) a motor can be attached to each wheel, and (iii) motor torque can be estimated precisely. These advantages enable us to (i) easily realize high-performance antilock braking systems and traction control systems with minor feedback control of each wheel, (ii) control chassis motion, for example, direct yaw control, and (iii) estimate road surface condition. We have developed test vehicles and confirmed the effectiveness of the proposed methods. Recently, we have manufactured small EVs that are powered only by supercapacitors. Supercapacitors have long operating life, large current density, and are environmental friendly. Furthermore, their energy level can be estimated from their terminal voltage. Because EVs powered by supercapacitors can run for more than 20 min by charging only for 30 s, recharging EVs will not be a major problem. In the future, EVs will be recharged via contactless power transfer. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
57.
A micro gas chromatography (µGC) instrument applying a high performance chip column fabricated on a silicon wafer was developed. Experimental results of the chip column and protyping of a µGC instrument are described. Approximately 35 000 theoretical plates were generated with the chip column coated liquid phase (5% phenyl-/95% dimethyl-polysiloxane). The theoretical plates of the chip column were close to those of the capillary column. Experimental minimum height equivalent to a theoretical plate (HETP, Hmin) of the chip column was 1.2 times higher than the calculated Hmin. A prototype µGC applying the chip column was developed. The µGC generated approximately 35 000 theoretical plates, similar to the theoretical plates obtained by a commercial GC instrument. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
58.
Glioblastoma (GBM) is the leading malignant intracranial tumor and is associated with a poor prognosis. Highly purified, activated natural killer (NK) cells, designated as genuine induced NK cells (GiNKs), represent a promising immunotherapy for GBM. We evaluated the anti-tumor effect of GiNKs in association with the programmed death 1(PD-1)/PD-ligand 1 (PD-L1) immune checkpoint pathway. We determined the level of PD-1 expression, a receptor known to down-regulate the immune response against malignancy, on GiNKs. PD-L1 expression on glioma cell lines (GBM-like cell line U87MG, and GBM cell line T98G) was also determined. To evaluate the anti-tumor activity of GiNKs in vivo, we used a xenograft model of subcutaneously implanted U87MG cells in immunocompromised NOG mice. The GiNKs expressed very low levels of PD-1. Although PD-L1 was expressed on U87MG and T98G cells, the expression levels were highly variable. Our xenograft model revealed that the retro-orbital administration of GiNKs and interleukin-2 (IL-2) prolonged the survival of NOG mice bearing subcutaneous U87MG-derived tumors. PD-1 blocking antibodies did not have an additive effect with GiNKs for prolonging survival. GiNKs may represent a promising cell-based immunotherapy for patients with GBM and are minimally affected by the PD-1/PD-L1 immune evasion axis in GBM.  相似文献   
59.
Copolymerization is a useful way of modifying the physical properties of a material to meet specific needs, but it can result in a significant light scattering loss due to dielectric fluctuations in the material. Ideal random copolymers are known to be more transparent; however, the light-scattering properties of such copolymers in bulk have not been fully studied. In this paper, two representative ideal random copolymers were synthesized: methyl methacrylate (MMA)/benzyl methacrylate (BzMA) and MMA/2,2,2-trifluoroethyl methacrylate (TFEMA). The effects of copolymer composition and polymerization temperature on the light-scattering properties were investigated. Polarized light scattering (VV) in copolymers was more sensitive to the polymerization temperature. Higher temperatures were necessary to homogenize the dielectric fluctuations and minimize excess light scattering. However, once the heterogeneous structures vanished, the copolymer bulk exhibited low scattering losses, which are comparable with homopolymers, over the entire range of copolymer compositions.  相似文献   
60.
This paper describes a business intelligence application of neural networks in analyzing consumer heterogeneity in the context of eating-out behavior in Taiwan. We apply a neural network rule extraction algorithm which automatically groups the consumers into identifiable segments according to their socio-demographic information. Within each of these segments, the consumers are distinguished between those who eat-out frequently from those who do not based on their psychological traits and eat-out considerations. The data set for this study has been collected through a survey of 800 Taiwanese consumers. Demographic information such as gender, age and income were recorded. In addition, information about their psychological traits and eating-out considerations that might influence the frequency of eating-out were obtained. The results of our data analysis show that the neural network rule extraction algorithm is able to find distinct consumer segments and predict the consumers within each segment with good accuracy.  相似文献   
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