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41.
Choosing the right compounds to synthesise from large virtual combinatorial libraries is a current challenge for the pharmaceutical industry. Herein we describe a highly optimised method that aligns lead‐like properties with compound diversity. The methods are illustrated by considering a two‐dimensional library based on the interesting spirocyclic bis‐azetidine template.

  相似文献   

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This study examines the impact of financial development on energy consumption in a sample of 9 Central and Eastern European frontier economies. Several different measures of financial development are examined including bank related variables and stock market variables. The empirical results, obtained from dynamic panel demand models, show a positive and statistically significant relationship between financial development and energy consumption when financial development is measured using banking variables like deposit money bank assets to GDP, financial system deposits to GDP, or liquid liabilities to GDP. Of the three stock market variables investigated, only one, stock market turnover, has a positive and statistically significant impact on energy consumption. Both short-run and long-run elasticities are presented. The implications of these results for energy policy are discussed.  相似文献   
44.
Using two pilot plants operated in parallel, treating settled sewage the removal of the detergent builder zeolite type A during primary sedimentation has been studied. With one zeolite free pilot plant acting as a control to the other it was also possible to determine the effect of zeolite on suspended solids and heavy metal removal over a range of hydraulic loadings. At both influent concentrations of zeolite studied (30 and 60 mg l−1) zeolite removal was substantial under all conditions. No evidence of enhanced removal of suspended solids in the presence of zeolite was observed. Removals of lead, zinc, copper and chromium were slightly enhanced in some experiments. The observed improvements in metal removal appeared to be strongly influenced by the sewage matrix.  相似文献   
45.
Electrochemical hydrogen pumping using a high-temperature (>100 °C) polybenzimidazole (PBI) membrane was demonstrated under non-humidified and humidified conditions at ambient pressures. Relatively low voltages were required to operate the pump over a wide range of hydrogen flow rates. The advantages of the high-temperature capability were shown by operating the pump on reformate feed gas mixtures containing various amounts of CO and CO2. Gas purity measurements on the cathode gas product were conducted and significant reductions in gas impurities were detected. The applicability of the PBI membrane for electrochemical hydrogen pumping and its durability under typical operating conditions were established with tests that lasted for nearly 4000 h.  相似文献   
46.
Recent empirical research has found evidence of a relationship between oil price movements and stock prices. Most published research investigates the relationship between oil price movements and stock prices using either economy-wide measures of stock prices or industry sector measures of stock prices. An important question that has largely gone unanswered relates to the relationship between oil prices and stock prices when the size of firms is allowed to vary. Relative to large firms, do oil price movements have larger or smaller impacts on the stock prices of small- or medium-sized firms? The answer to this question could have important policy implications that affect economic growth and prosperity. In this paper, a panel of firms is followed over a 17-year period to investigate the relationship between oil price movements, firm size, and stock prices. Evidence is found that shows the relationship between oil price movements and stock prices does vary with firm size and the relationship is strongest for medium-sized firms.  相似文献   
47.
An 8-b pipelined ADC constructed in 0.13-μm CMOS is described. This ADC uses a dual-supply technique to yield 8-b performance at a sampling rate of 125 MS/s while consuming 30 mW from 1.8-V and 1.2-V supplies. Active area is 0.4 mm2. Numerous challenges associated with this choice of process technology were overcome, such as limited dynamic range, copper metallization and the effects of gate oxide leakage.  相似文献   
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[Correction Notice: An erratum for this article was reported in Vol 18(3) of Experimental and Clinical Psychopharmacology (see record 2010-11933-011). In the article the authors find it necessary to redefine the thresholding procedure used for data analyses, due to problems in the Brain Voyager software. This does not affect the main findings of the paper.] Reactivity to smoking-related cues may play a role in the maintenance of smoking behavior and may change depending on smoking status. Whether smoking cue-related functional MRI (fMRI) reactivity differs between active smoking and extended smoking abstinence states currently is unknown. We used fMRI to measure brain reactivity in response to smoking-related versus neutral images in 13 tobacco-dependent subjects before a smoking cessation attempt and again during extended smoking abstinence (52 ± 11 days) aided by nicotine replacement therapy. Prequit smoking cue induced fMRI activity patterns paralleled those reported in prior smoking cue reactivity fMRI studies. Greater fMRI activity was detected during extended smoking abstinence than during the prequit assessment subcortically in the caudate nucleus and cortically in prefrontal (BA 6, 9, 44, 46), primary somatosensory (BA 1, 2, 3), temporal (BA 22, 41, 42), parietal (BA 7, 40) anterior cingulate (BA 24, 32), and posterior cingulate (BA 31) cortex. These data suggest that during extended smoking abstinence, fMRI reactivity to smoking versus neutral stimuli persists in brain areas involved in attention, somatosensory processing, motor planning, and conditioned cue responding. In some brain regions, fMRI smoking cue reactivity is increased during extended smoking abstinence in comparison to the prequit state, which may contribute to persisting relapse vulnerability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
Ethernet passive optical networks (EPONs) have attracted considerable attention from the industry, as they offer a simple, highly flexible and cost-effective solution to the problem of providing broadband access to a customer. The authors present a new approach to bandwidth allocation in EPONs where the optical line terminator (OLT) has full control over the access mechanism. This results in much simpler optical network unit (ONU) architecture. It is shown that such an OLT-centric architecture offers full support for differentiated services and makes enforcement of service level agreements possible. Extensive simulation experiments show that bandwidth allocation algorithms deployed in such a centralised environment can deliver good performance in terms of average and maximum packet delay. The authors introduce two new algorithms that target SLA-aware EPONs and provide a good protection of offered quality of service against interference from other sources.  相似文献   
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