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951.
952.
Sphinganine‐Like Biogenesis of (E)‐1‐Nitropentadec‐1‐ene in Termite Soldiers of the Genus Prorhinotermes 下载免费PDF全文
Dr. Anna Jirošová Dr. Pavel Majer Andrej Jančařík Klára Dolejšová Dr. Richard Tykva Dr. Jan Šobotník Dr. Pavel Jiroš Dr. Robert Hanus 《Chembiochem : a European journal of chemical biology》2014,15(4):533-536
In 1974, (E)‐1‐nitropentadec‐1‐ene, a strong lipophilic contact poison of soldiers of the termite genus Prorhinotermes, was the first‐described insect‐produced nitro compound. However, its biosynthesis remained unknown. In the present study, we tested the hypothesis that (E)‐1‐nitropentadec‐1‐ene biosynthesis originates with condensation of amino acids with tetradecanoic acid. By using in vivo experiments with radiolabeled and deuterium‐labeled putative precursors, we show that (E)‐1‐nitropentadec‐1‐ene is synthesized by the soldiers from glycine or L ‐serine and tetradecanoic acid. We propose and discuss three possible biosynthetic pathways. 相似文献
953.
Immune and Anticancer Responses Elicited by Fully Synthetic Aberrantly Glycosylated MUC1 Tripartite Vaccines Modified by a TLR2 or TLR9 Agonist 下载免费PDF全文
Dr. Abu‐Baker M. Abdel‐Aal Dr. Vani Lakshminarayanan Dr. Pamela Thompson Nitin Supekar Judy M. Bradley Dr. Margreet A. Wolfert Prof. Dr. Peter A. Cohen Prof. Dr. Sandra J. Gendler Prof. Dr. Geert‐Jan Boons 《Chembiochem : a European journal of chemical biology》2014,15(10):1508-1513
The mucin MUC1 is overexpressed and aberrantly glycosylated by many epithelial cancer cells manifested by truncated O‐linked saccharides. Although tumor‐associated MUC1 has generated considerable attention because of its potential for the development of a therapeutic cancer vaccine, it has been difficult to design constructs that consistently induce cytotoxic T‐lymphocytes (CTLs) and ADCC‐mediating antibodies specific for the tumor form of MUC1. We have designed, chemically synthesized, and immunologically examined vaccine candidates each composed of a glycopeptide derived from MUC1, a promiscuous Thelper peptide, and a TLR2 (Pam3CysSK4) or TLR9 (CpG‐ODN 1826) agonist. It was found that the Pam3CysSK4‐containing compound elicits more potent antigenic and cellular immune responses, resulting in a therapeutic effect in a mouse model of mammary cancer. It is thus shown, for the first time, that the nature of an inbuilt adjuvant of a tripartite vaccine can significantly impact the quality of immune responses elicited against a tumor‐associated glycopeptide. The unique adjuvant properties of Pam3CysSK4, which can reduce the suppressive function of regulatory T cells and enhance the cytotoxicity of tumor‐specific CTLs, are likely responsible for the superior properties of the vaccine candidate 1 . 相似文献
954.
955.
The DiPPro Approach: Synthesis,Hydrolysis, and Antiviral Activity of Lipophilic d4T Diphosphate Prodrugs 下载免费PDF全文
Bioreversible protection of the β‐phosphate group of nucleoside diphosphates (NDPs) as bis(acyloxybenzyl)phosphate esters is presented. To investigate the structure–activity relationship of these potential NDP prodrugs (DiPPro drugs) a series of DiPPro compounds was synthesized bearing fatty acids of various lengths and d4T as a model nucleoside. For synthesis of the lipophilically modified diphosphate group, preformed phosphoramidites were allowed to react with nucleotides, and the β‐PIII moiety was subsequently oxidized. The chemical and enzymatic stability of these prodrugs was studied in different media such as phosphate buffer (pH 7.3) or CEM cell extracts. In all media, the hydrolysis rate was clearly dependent on the acyl moiety and decreased with increasing alkyl chain length. The compounds showed a markedly lower half‐life in cell extracts than in pH 7.3 phosphate buffer due to the presence of enzyme‐catalyzed cleavage. In all media, the DiPPro compounds released d4T diphosphate (d4TDP) as the main product beside d4TMP. In antiviral assays, the compounds proved to be at least as potent as d4T against HIV‐1 and 2 in wild‐type CEM/0 cells. As a proof of concept, compounds with longer acyl residues showed very good anti‐HIV activities in thymidine‐kinase‐deficient cells (CEM/TK?), indicating their ability to penetrate cell membranes and the delivery of phosphorylated metabolites. 相似文献
956.
Since the 1960s, researchers have provided short-term and long-term explanations for low productivity growth in the construction industry. In retrospect, the main challenge appears to be the measurement of changes in heterogeneous input and output qualities. The aim here is to review earlier construction productivity research and to compare it with more recent approaches to quality measurement used when analysing services productivity, ultimately intending to provide guidance for using performance data from construction projects. Relying on the EU KLEMS database, industries with similar patterns of productivity growth are identified, primarily the business services industry. In services productivity analyses, the attempts to introduce output quality measures reflecting customer satisfaction are particularly interesting, as this creates a link to productivity effects on clients. A conclusion is that it should be possible to use the increasing volume of performance indicator data collected for construction project benchmarking for extending the range of output quality variables. However, resource constraints imply that it is infeasible to base industry productivity statistics on project level data reflecting customer satisfaction and customer productivity effects. 相似文献
957.
Jan Potac Thomas K. Thiis 《土木工程与建筑:英文版》2014,(7):907-919
A HVAC (heating ventilating and air conditioning) system is generally designed to ventilate an indoor space. In windy and snowy climates dispersed snow particles in ambient air can enter the intake duct, potentially causing a serious problem. The study addresses the influence of suction volumetric flow rates, the potential discrepancy of snow intake based upon the wind direction in relation to the intake vent, and the possible difference in amounts of infiltrated snow particles in varying intake vent design and locations. The necessary characteristic quantities are defined. The simulation results show the rate of infiltration and the efficiency of the chosen intake designs. The magnitude and direction of wind influences snow infiltration significantly. The daily amount of infiltrated snow is introduced to be the characteristic measure of the infiltration in design of the HVAC systems. 相似文献
958.
Industrial halls are mainly low-rise rectangular-shaped structures of simple construction. The relatively loose requirements in space conditioning and the comparatively high internal heat gain make the approach in industrial hall design quite different from that of office building design. The simplicity in building geometry and construction method allows the investigation of energy consumption for building services to be limited to a few demand-side parameters, namely, resistance of the roof and wall insulation, airtightness, and amount of daylighting. This paper investigates the impact of varying these demand-side parameters on the energy consumption for space conditioning and lighting for a typical industrial hall. Through building energy simulation, such impacts can be investigated, and by applying optimization, the configurations of the most optimal combinations of demand-side parameters with the lowest energy consumption can be identified. The result suggests that there is a significant energy-saving potential. For industrial halls, energy consumption for building services can be very sensitive to changes in the process load and occupancy pattern, which in reality, fluctuate widely due to economic cycles, and other factors. Optimized design solutions for industrial halls intended for a particular process load and occupancy pattern might not perform as predicted due to potential changes. To account for potential changes, uncertainty analysis can be performed to determine if the optimized design solutions are in fact robust enough to such changes and to identify solutions that are less susceptible to uncertainty. 相似文献
959.
Barış Özgül Jan Langer Juanjo Noguera Kees Vissers 《Analog Integrated Circuits and Signal Processing》2014,78(3):573-587
In this paper we present a software programmable design flow that facilitates the implementation and integration of efficient digital pre-distortion (DPD) solutions on the leading-edge field programmable gate arrays, combining industry-standard embedded processors and programmable logic fabric into one chip. In addition to software programmability, another key contribution of this design flow is the flexible partitioning of functionality among the hardware and software components, depending on the complexity of the DPD parameter estimation algorithm in use. We have applied processor-specific optimizations to the software implementation and used Vivado high-level synthesis (HLS) tool as the design tool for the programmable logic. Furthermore, we have compared two different techniques for the integration of hardware and software components, where we have chosen the one with better area/latency trade-off. We present a comprehensive study reporting the DPD parameter update times when exploring the partitioning of the functionality among hardware and software. For low-complexity algorithms, we show that a software-only solution is applicable after carrying out the processor-specific software optimizations. For higher-complexity algorithms, we use Vivado HLS to accelerate the time-consuming blocks in the programmable logic, leading to a speed-up factor of up to 7× in the overall algorithm execution time. We present the performance results for two target devices. We also show that our accelerators use only a small portion of the programmable logic fabric on these devices and that a significant reduction of the system’s energy consumption can be obtained by leveraging the FPGA fabric. 相似文献
960.
Natália Tomašovičová Milan Timko Vlasta Závišová Anežka Hashim Jan Jadzyn Xavier Chaud Eric Beaugnon Peter Kopčanský 《International Journal of Thermophysics》2014,35(11):2044-2053
We have studied the influence of electric and magnetic fields on the orientational structure of ferronematics based on a thermotropic nematic 4-trans-4 \(^{\prime }\) -n-hexylcyclohexyl-isothiocyanato-benzene (6CHBT). The 6CHBT liquid crystal has been dissolved in phenyl isothiocyanate and doped with rod-like or chain-like magnetic particles. In such a mixture, the phase transition from an isotropic to a nematic phase is via a droplet state, i.e., coexistence of nematic and isotropic phases. The obtained results showed that a combination of the electric and magnetic fields can change the character of a phase transition from the isotropic to the nematic phase via the droplet state in such systems. Moreover, magneto-dielectric measurements of structural transitions showed the magnetic field induced a shift of the phase transition temperature from the isotropic to the droplet state. 相似文献