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Some indication of the use of Phenidone in PQ developer systems in large scale motion picture laboratory practice is given. Various characteristics, which were examined on a plant scale before MQ systems were abandoned in favour of PQ systems, are discussed; the stabilities and economics of the two systems are compared. 相似文献
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A practical localization technology for underground drift networks—such as those excavated in the practice of underground mining—has yet to become commercially available. This paper focuses on the problem of mapping GPS‐deprived underground environments with the eventual goal of using these maps for navigation. Recent industry‐directed work in the creation of a landmark‐bounded occupancy grid mapping tool that combines odometry, scanning laser data, and sporadically placed passive RFID tags is described. Unlike other work, the suggested approach holds the philosophy that precise localization of the actual landmark locations is not necessary; rather, landmarks serve as a global means for partitioning the map. Successful field experiments were conducted in two underground environments, with the results used to conduct a basic analysis of the described method. © 2012 Wiley Periodicals, Inc. 相似文献
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Susan Robinson 《Rocks & Minerals》2015,90(6):569-570
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Pedro J. Ballester Martina Mangold Nigel I. Howard Richard L. Marchese Robinson Chris Abell Jochen Blumberger John B. O. Mitchell 《Journal of the Royal Society Interface》2012,9(77):3196-3207
One of the initial steps of modern drug discovery is the identification of small organic molecules able to inhibit a target macromolecule of therapeutic interest. A small proportion of these hits are further developed into lead compounds, which in turn may ultimately lead to a marketed drug. A commonly used screening protocol used for this task is high-throughput screening (HTS). However, the performance of HTS against antibacterial targets has generally been unsatisfactory, with high costs and low rates of hit identification. Here, we present a novel computational methodology that is able to identify a high proportion of structurally diverse inhibitors by searching unusually large molecular databases in a time-, cost- and resource-efficient manner. This virtual screening methodology was tested prospectively on two versions of an antibacterial target (type II dehydroquinase from Mycobacterium tuberculosis and Streptomyces coelicolor), for which HTS has not provided satisfactory results and consequently practically all known inhibitors are derivatives of the same core scaffold. Overall, our protocols identified 100 new inhibitors, with calculated Ki ranging from 4 to 250 μM (confirmed hit rates are 60% and 62% against each version of the target). Most importantly, over 50 new active molecular scaffolds were discovered that underscore the benefits that a wide application of prospectively validated in silico screening tools is likely to bring to antibacterial hit identification. 相似文献
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