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991.
Functional Chromatography Reveals Three Natural Products that Target the Same Protein with Distinct Mechanisms of Action 下载免费PDF全文
Dr. Min Jin Kang Dr. Tongde Wu Dr. E. M. Kithsiri Wijeratne Eric C. Lau Damian J. Mason Celestina Mesa Joseph Tillotson Prof. Dr. Donna D. Zhang Prof. Dr. A. A. Leslie Gunatilaka Dr. James J. La Clair Prof. Dr. Eli Chapman 《Chembiochem : a European journal of chemical biology》2014,15(14):2125-2131
Access to lead compounds with defined molecular targets continues to be a barrier to the translation of natural product resources. As a solution, we developed a system that uses discrete, recombinant proteins as the vehicles for natural product isolation. Here, we describe the use of this functional chromatographic method to identify natural products that bind to the AAA+ chaperone, p97, a promising cancer target. Application of this method to a panel of fungal and plant extracts identified rheoemodin, 1‐hydroxydehydroherbarin, and phomapyrrolidone A as distinct p97 modulators. Excitingly, each of these molecules displayed a unique mechanism of p97 modulation. This discovery provides strong support for the application of functional chromatography to the discovery of protein modulators that would likely escape traditional high‐throughput or phenotypic screening platforms. 相似文献
992.
筛余砂浆气孔结构对其28d抗压强度的影响 总被引:1,自引:0,他引:1
为便于高性能混凝土引气剂的开发和应用,采用定量体视学图像分析法测定掺有11种引气剂的混凝土筛余砂浆气孔结构参数,运用灰色关联分析方法研究不同范围孔径对筛余砂浆28d抗压强度的影响,并采用显微硬度仪对筛余砂浆界面过渡区显微硬度进行了测试分析.结果表明:筛余砂浆28d抗压强度与各范围孔径的灰色关联度均为负值,但不同范围孔径对筛余砂浆28d抗压强度的影响有所不同.在筛余砂浆总孔隙率相近条件下,增加10~200μm孔径的孔隙率,降低200~1600μm孔径的孔隙率,可使砂浆气孔的平均孔径减小,砂浆界面过渡区宽度缩短、显微硬度提高,最终减小因引气而造成的砂浆28d抗压强度损失. 相似文献
993.
994.
Cooperative communication technology exploiting distributed spatial diversity is a promising solution for the future high data-rate cellular and ad-hoc wireless communications. To characterize the performance of a cooperative network, the cooperative diversity is commonly used. In this paper, we revisit the concept of diversity and look into the essence of cooperative diversity. We analyze the diversity performance of a general cooperative relaying system with multiple branches. Moreover, each branch consists of one or more hops. Unlike in other analyses, the assumptions that each node being only equipped with a single antenna and that all channel characteristics belonging to the same family are NOT required in our study. Using the decode-and-forward (DF) relaying protocol as an illustration, we provide analytical results on the diversity gain and the coding gain. The results also encompass most of the existing results as special cases. We further show the relationship between the diversity order of a branch and those of the constituent links; and the relationship between the diversity order of the network and those of the constituent branches. In particular, we show that for the uncoded DF protocol, the full diversity order can be achieved by using simple hard-decision detection at the destination. The requirement is to set appropriate signal-to-noise-ratio (SNR) thresholds for the multi-hop branches. To improve the bandwidth efficiency, we also randomly select one branch, among those branches satisfying the SNR-threshold requirement, for the transmission. We show that such a scheme accomplishes the full diversity order and produces a good error performance. 相似文献
995.
996.
997.
Nanoparticles of Conjugated Polymers Prepared from Phase‐Separated Films of Phospholipids and Polymers for Biomedical Applications 下载免费PDF全文
998.
Guoyun Zhou Chia-Yun Chen Ziyin Lin Liyi Li Zhihua Tao Wei He Ching Ping Wong 《Journal of Materials Science: Materials in Electronics》2014,25(3):1341-1347
The effects of manganese sulfate monohydrate (denoted as MSM) on the properties of electroless Ni–P thin-film were investigated. The properties of Ni–P thin-film were examined by means of atomic force microscopy (AFM), cyclic voltammetry, scanning electron microscopy (SEM), X-ray diffraction, energy-dispersive X-ray spectrometer and X-ray photoelectron spectroscopy. AFM and SEM results showed that MSM had significant influences on the morphology, including the formation of smaller nodules, nano-size particles boundaries on both surface and inside of nodules. Due to the specific topologies, the resistance of Ni–P thin-film deposited with MSM was increased. Based on the characterization results, we summarized that the Mn2+ or Mn2+-compound were primarily confirmed to act as the stabilizer in Ni–P electroless process. Moreover, the verification test for Ni–P thin-film in application as embedded resistor was carried out through electrical, thermal stability examination by means of current–voltage (I–V), temperature coefficient of resistance and thermal shock tests, respectively. Experiment results demonstrated the Ni–P thin-film deposited with MSM is qualified for embedded resistors. 相似文献
999.
Qiujuan Man Wen Sun Feng Yang Chengcheng Qiu Yuanyuan Zhao Guangda Hu 《Journal of Materials Science: Materials in Electronics》2014,25(3):1269-1274
Predominantly (110)-oriented BiFeO3 (BFO) thin films were deposited on indium tin oxide/glass substrates using a metal organic decomposition process by controlling the preheating temperature. The structure evolution with film thickness at different preheating temperatures was investigated to clarify the growth mode of (110)-predominant BFO film. The formation of the (110)-oriented BFO film is due to the low-temperature nucleation of (110)-oriented grains preheated at 425 °C. In the Au/BFO(110)/ITO heterostructure, a polarization-modulated bistable resistive switching behavior with high ratio of resistance and large diode current characteristics was observed, which makes the heterostructure attractive for application in resistive ferroelectric memory. 相似文献
1000.
岩体结构面抗剪强度尺寸效应变化规律的研究需要在专门的多尺度岩体结构面抗剪强度直剪试验机上进行,以获得稳定的抗剪强度力学参数。为保证测试数据的可靠性,在满足测试载荷范围为2~1000 kN时要求恒定荷载示值精度为1%。由于现有测试系统的技术限制,无法实现在同一台设备上进行全部荷载的试验。为此,首先在提出一种设备荷载分级方法的基础上开发了一种多尺度岩体结构面抗剪强度直剪试验一体机,在满足测试精度的要求下分3级尺度直剪仪进行直剪测试,每一级尺度直剪仪设置了荷载重叠区以保证测试数据的等效性。最后对该直剪试验一体机的精度和载荷范围进行了测试,通过了多尺度试样的测试要求。目前该多尺度岩体结构面抗剪直剪试验一体机为多尺度试样的测试研究提供了平台。 相似文献