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421.
We study a quantum liquid of particles interacting via a long-ranged two-body potential in three dimensions where the original particles are supposed to be either bosons or fermions. We show that such liquids exhibit the nature of a quantum liquid with fractional exclusion statistics. In both quantum liquids enlarged pseudo-Fermi surfaces are formed from bosons and fermions, although with different excitations. Hence, we conclude that the microscopic origin of exclusion statistics comes from the nature of long-ranged two-body interactions between the particles. 相似文献
422.
Background
Anaesthesia is commonly employed prior to surgical investigations and to permit icv injections in rodents. Indeed it is standard practise in many studies examining the subsequent actions of hormones and growth factors on the brain. Recent evidence that the basal activity of specific intracellular signalling proteins can be affected by anaesthesia prompted us to examine the effect of anaesthesia not only on the basal activity but also the insulin sensitivity of the major insulin signalling pathways. 相似文献423.
Quantifying DNA damage by gel electrophoresis, electronic imaging and number-average length analysis
DNA damages that can be converted to single- or double strand breaks can be quantified by separating DNA by gel electrophoresis and obtaining a quantitative image of the resulting distribution of DNA in the gel. We review the theory of this method and discuss its implementation, including the charge-coupled device (CCD) camera systems we developed to acquire images of fluorophore labeled DNA. 相似文献
424.
Holland RD Rafii F Heinze TM Sutherland JB Voorhees KJ Lay JO 《Rapid communications in mass spectrometry : RCM》2000,14(10):911-917
Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectra of bacterial proteins were obtained from water, lettuce and cloth samples contaminated with Shigella flexneri, Escherichia coli, and Aeromonas hydrophila. Spectra were obtained using proteins directly isolated from water (or water used for rinsing samples) without culturing the bacteria. For S. flexneri and E. coli, two marker ions for specific proteins associated with a virulence-related property (acid resistance) were easily detected. For A. hydrophila, ions from two specifically selected marker proteins, as well as ions from the larger group of proteins isolated from pure cultures, all matched spectra from a contaminated water sample, providing strong evidence that A. hydrophila was the bacterial contaminant. Rinse water from contaminated lettuce and cloth samples showed the same marker ions as the contaminated water samples. 相似文献
425.
Sutherland TE Andersen OA Betou M Eggleston IM Maizels RM van Aalten D Allen JE 《Chemistry & biology》2011,18(5):569-579
Acidic mammalian chitinase (AMCase) is produced in the lung during allergic inflammation and asthma, and inhibition of enzymatic activity has been considered as a therapeutic strategy. However, most chitinase inhibitors are nonselective, additionally inhibiting chitotriosidase activity. Here, we describe bisdionin F, a competitive AMCase inhibitor with 20-fold selectivity for AMCase over chitotriosidase, designed by?utilizing the AMCase crystal structure and dicaffeine scaffold. In a murine model of allergic inflammation, bisdionin F-treatment attenuated chitinase activity and alleviated the primary features of allergic inflammation including eosinophilia. However, selective AMCase inhibition by bisdionin F also caused dramatic and unexpected neutrophilia in the lungs. This class of inhibitor will be a powerful tool to dissect the functions of mammalian chitinases in disease and represents a synthetically accessible scaffold to optimize inhibitory properties in terms of airway inflammation. 相似文献
426.
Ximena Zarate Eduardo Schott Leonor Alvarado‐Soto Todd C. Sutherland 《International journal of quantum chemistry》2013,113(20):2287-2294
A theoretical study has been carried out on two methoxyphenyl derivatives (tetrakis‐(p‐methoxyphenyl)‐ porphyrin and the Zn‐containing complex), which are the reduced size representation of the alkyl peripheral substituent systems. The aim is to study the electronic interactions on these aromatic cores which is one of the most important properties in discotic liquid crystals. Their face‐to‐face dimeric conformation systems were studied in order to evaluate charge transport properties, by assessing the intermolecular charge transfer integrals “t” in the context of the Marcus electron transfer theory. The intermolecular transfer integral has been calculated from the matrix elements of the Kohn–Sham Hamiltonian including dispersion correction for noncovalent interacting systems. The results indicate that the effect of the Zn center in these porphyrins is nearly negligible and both studied systems can act as electron carriers, which are also seen in the bonding interaction of the LUMO orbitals. © 2013 Wiley Periodicals, Inc. 相似文献
427.
Alaa S. Abd-el-aziz Adam Piórko Andrzej S. Baranski Ronald G. Sutherland 《合成通讯》2013,43(11-12):1865-1870
Electrochemical reduction of the cyclopentadienyliron hexafluorophosphates of benzophenone, o-chlorophenyldibenzoylmethane and diethyl ethylphenylmalonate led to the liberation of arenes without reduction of keto or ester groups in over 85% yields. 相似文献
428.
The aim of this research is to compare two continuous extraction technologies, intermittent counter-current extraction (ICcE) and dual flow counter-current chromatography (DFCCC), in terms of loading and throughput using the GUESSmix, and show the advantages and disadvantages of the two methods. A model sample containing caffeine, vanillin, naringenin and carvone, with a total load of 11.2 g, was employed with a hexane-ethyl acetate-methanol-water (2:3:2:3) phase system to evaluate an ICcE method on a preparative (912 ml coil volume) DE-Midi instrument. While DFCCC was carried out on a specially designed preparative (561 ml coil volume) bobbin installed in a similar Midi instrument case. While similar throughputs of 7.8 g/h and 6.9 g/h were achieved for the ICcE and DFCCC methods respectively, ICcE was demonstrated to have a number of advantages over DFCCC. 相似文献
429.
Ma W Li DW Sutherland TC Li Y Long YT Chen HY 《Journal of the American Chemical Society》2011,133(32):12366-12369
Here, we report the reversible interconversion between NADH and NAD(+) at a low overpotential, which is in part mediated by ubiquinone embedded in a biomimetic membrane to mimic the initial stages of respiration. This system can be used as a platform to examine biologically relevant electroactive molecules embedded in a natural membrane environment and provide new insights into the mechanism of biological redox cycling. 相似文献
430.
A. J. Miles Robert W. Janes A. Brown D. T. Clarke J. C. Sutherland Y. Tao B. A. Wallace S. V. Hoffmann 《Journal of synchrotron radiation》2008,15(4):420-422
New high‐flux synchrotron radiation circular dichroism (SRCD) beamlines are providing important information for structural biology, but can potentially cause denaturation of the protein samples under investigation. This effect has been studied at the new CD1 dedicated SRCD beamline at ISA in Denmark, where radiation‐induced thermal damage effects were observed, depending not only on the radiation flux but also on the focal spot size of the light. Comparisons with similar studies at other SRCD facilities worldwide has lead to the estimation of a flux density threshold under which SRCD beamlines should be operated when samples are to be exposed to low‐wavelength vacuum ultraviolet radiation for extended periods of time. 相似文献