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21.
We describe the design and proof of concept of a pair of chemical probes for investigating DNA-protein interactions-specifically, the incorporation of 7-bromo-7-deazaadenine and 3-bromo-3-deazaadenine 2'-deoxynucleosides (Br(7)C(7)dA and Br(3)C(3)dA) into oligodeoxynucleotides (ODNs)-and their utility. Whereas the bromo substituent of the Br(7)C(7)dA unit in an ODN duplex acts sterically to inhibit binding with NF-kappaB, which interacts with the duplex in its major groove, the bromo substituent of the Br(3)C(3)dA unit acts sterically to inhibit binding with RNase H, which interacts with the duplex in its minor groove. In addition, the utilization of ODNs containing 7-deazaadenine and 3-deazaadenine 2'-deoxynucleosides (C(7)dA and C(3)dA), together with the pair of chemical probes, afforded valuable information on the requirement for nitrogen atoms located in either the major or minor grooves. Accordingly, we were able to show the utility of ODNs containing Br(7)C(7)dA, Br(3)C(3)dA, C(7)dA, and C(3)dA for the investigation of DNA-protein interactions.  相似文献   
22.
Pervaporation (PV) is a membrane technology that holds great promise for industrial applications. To better understand the PV mechanism, PV dehydrations of various types of organic solvents (methanol, ethanol, iso-propanol, tert-butanol, and acetone) were performed on five types of organosilica and two types of silicon carbide-based membranes, all with different pore sizes. Water permeance was dependent on the types of organic aqueous solutions, which suggested that organic solvents penetrated the pores and hindered the permeation of water. In addition, water permeance of various types of membranes in PV was well correlated with hydrogen permeance in single-gas permeation. Furthermore, a clear correlation was obtained between the permeance ratio in PV and that in single-gas permeation, which was confirmed via the modified-gas translation model. These correlations make it possible to use single-gas permeation properties to predict PV performance.  相似文献   
23.
24.
电子纸(EPD)技术有一些瑕疵.缺乏市场成熟性。电子纸用户是少数,围绕EPD的生态体系和下层基础构建还在发展中,比如LCD显示器拥有众多的标准驱动电路支持,但可以设想,EPD的瑕疵会随着市场的发展而淡化。EPD的其它缺陷还包括有电压要求:即高压驱动(〉10V),尽管驱动电流非曾低。随着时间推移EPD比其它显示媒介缩短了响应时间。当然,尽管存在这些缺点,但都会在:降来得到改正,EPD为各种创新应用提供了独到的方案。分段式EPD凭据其超薄、不规謦性、柔韧性能,可为各种类型的显示器提供高对比显示,通过运用低功耗电子系统来匹配低功耗图形显示,设计师可以实现产品便携和长寿电池的双重性能。  相似文献   
25.
High-voltage power distribution systems are connected in a branch configuration so as to meet the need for highly reliable power service. When service is interrupted the faulty section is automatically isolated and the power supply is rerouted from an adjacent power distribution system thereby minimizing the service interruption area. The faulty section in the power distribution system is quickly located by means of time relays installed in the switchgears. The settings of those time relays, however, must be monitored constantly. For this reason, we have proposed a “section management method” which can supervise each section of the power distribution system. From this method, we developed a prototype automated distribution system for overall management of time relays through the use of internal software, facilities and customer feedback. This paper describes the section management of power distribution systems.  相似文献   
26.
A thermodynamic study was conducted of water vapor adsorption on four hydrophilic polymers (agar, carboxymethyl cellulose, gelatin, and maize starch) at 12 and 25°C. Monolayer coverage amounted, after correction for crystallinity, respectively, to 0.93, 1.46, 0.51, and 0.77 mol water/mol monomer. Evidence is adduced from the Bradley equation and thermodynamic data to indicate that at least during coverage with the second layer of water, the energy of adsorption is greater than that due to condensation alone. Differences in the amount of sorption and in the trend of values of ΔS?° and ΔH?° with the amount of sorbed water are related with differences in the strength of intermolecular association as affected by steric hindrances.  相似文献   
27.
Tumor-associated macrophages (TAMs) promote cancer cell proliferation and metastasis, as well as anti-tumor immune suppression. Recent studies have shown that tumors enhance the recruitment and differentiation of TAMs, but the detailed mechanisms have not been clarified. We thus examined the influence of cancer cells on the differentiation of monocytes to TAM subsets, including CD163+, CD204+, and CD206+ cells, in oral squamous cell carcinoma (OSCC) using immunohistochemistry, flow cytometry, and a cytokine array. Furthermore, we investigated the effect of OSCC cells (HSC-2, SQUU-A, and SQUU-B cells) on the differentiation of purified CD14+ cells to TAM subsets. The localization patterns of CD163+, CD204+, and CD206+ in OSCC sections were quite different. The expression of CD206 on CD14+ cells was significantly increased after the co-culture with OSCC cell lines, while the expressions of CD163 and CD204 on CD14+ cells showed no change. High concentrations of plasminogen activator inhibitor-1 (PAI-1) and interleukin-8 (IL-8) were detected in the conditioned medium of OSCC cell lines. PAI-1 and IL-8 stimulated CD14+ cells to express CD206. Moreover, there were positive correlations among the numbers of CD206+, PAI-1+, and IL-8+ cells in OSCC sections. These results suggest that PAI-1 and IL-8 produced by OSCC contribute to the differentiation of monocytes to CD206+ TAMs.  相似文献   
28.
In this paper, we introduce a backstepping control design of a wheeled inverted pendulum. Based on a second-order motion equation of the body angle, an adaptive integral backstepping controller is designed to stabilize the body angle. It is shown that the σ-modification rule in the adaptive update law guarantees the boundedness of the errors in estimating the time-varying signal that is an output of a linear system with every bounded input signal. Then, the stabilizing controller for the wheel angle is constructed by a PD-type positive feedback. The derived controller requires the full-state measurements. In the output feedback case, the K filter or the observer backstepping is needed. However, the structure of the controller becomes complicated. We propose a non-model-based differentiator based on the adaptive update law. Since the non-model-based differentiator does not require any knowledge of the dynamic structure of the signal, we can use it as a velocity estimator for unknown nonlinear systems. Therefore, we replaced the velocity measurement with the estimates by the non-model-based differentiator. Finally, simulation results for the proposed controller are presented.  相似文献   
29.
This paper introduces a technique to identify requirements discordances among stakeholders. This technique is validated in experiments. An extended version of the goal-oriented requirements elicitation method, named attributed goal-oriented analysis (AGORA), and its supporting tool are used. Two types of requirements discordances among stakeholders are defined: the first arises from the different interpretations by the stakeholders and the second is the result of different evaluations of preferences. Discordances are detected by the preference matrices in AGORA. Each preference matrix represents both preferences of each stakeholder and the estimated preferences of other stakeholders. A supporting tool for the AGORA method was developed. This tool is a groupware that seamlessly combines face-to-face meetings for goal elicitation and distributed individual sessions for scoring preference values. The experimental results showed that the proposed classification of discordances was sound and that the occurrences of the requirements discordances could be detected by preference matrices.  相似文献   
30.
ITER project's long time span and the nature of the instrumentation and control (I&C) procurement procedures for the Plant Systems require that the ITER Organization defines and follows well recognized standards which are used both by the industry and in physics experiments. The ITER I&C standards are defined in the Plant Control Design Handbook (PCDH) [1]. The ITER Organization has selected PCI Express and Ethernet for IO intercommunication to be used for plant system instrumentation for fast controllers. The decision on the usage of serialized I/O bus protocols is based on the impressive performance and the commercial availability. The form factors that will be supported by CODAC include PXIe, MicroTCA, and AdvancedTCA platforms. While the PXIe form factor is already well established for instrumentation purposes through the PXI Systems Alliance (www.pxisa.org), the AdvancedTCA and MicroTCA platforms which were originally targeted for the telecommunications market (www.picmg.org) are currently optimized and specified for instrumentation use through the xTCA extensions for physics [2]. The objective of this study is the evaluation of an integrated ATCA controller design using only commercial components.  相似文献   
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