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171.
Mass spectrometry (MS) based proteomics has brought a radical approach to systems biology, offering a platform to study complex biological functions. However, key proteomic technical challenges remain, mainly the inability to characterise the complete proteome of a cell due to the thousands of diverse, complex proteins expressed at an extremely wide concentration range. Currently, high throughput and efficient techniques to unambiguously identify and quantify proteins on a proteome-wide scale are in demand. Miniaturised analytical systems placed upstream of MS help us to attain these goals. One time-consuming step in traditional techniques is the in-solution digestion of proteins (4-20 h). This also has other drawbacks, including enzyme autoproteolysis, low efficiency, and manual operation. Furthermore, the identification of α-helical membrane proteins has remained a challenge due to their high hydrophobicity and lack of trypsin cleavage targets in transmembrane helices. We demonstrate a new rapidly produced glass/PDMS micro Immobilised Enzyme Reactor (μIMER) with enzymes covalently immobilised onto polyacrylic acid plasma-modified surfaces for the purpose of rapidly (as low as 30 s) generating peptides suitable for MS analysis. This μIMER also allows, for the first time, rapid digestion of insoluble proteins. Membrane protein identification through this method was achieved after just 4 min digestion time, up to 9-fold faster than either dual-stage in-solution digestion approaches or other commonly used bacterial membrane proteomic workflows. 相似文献
172.
Ramanathan A Wright KC Muniz SR Zelan M Hill WT Lobb CJ Helmerson K Phillips WD Campbell GK 《Physical review letters》2011,106(13):130401
We have created a long-lived (≈40 s) persistent current in a toroidal Bose-Einstein condensate held in an all-optical trap. A repulsive optical barrier across one side of the torus creates a tunable weak link in the condensate circuit, which can affect the current around the loop. Superflow stops abruptly at a barrier strength such that the local flow velocity at the barrier exceeds a critical velocity. The measured critical velocity is consistent with dissipation due to the creation of vortex-antivortex pairs. This system is the first realization of an elementary closed-loop atom circuit. 相似文献
173.
174.
We experimentally and numerically investigate the intracavity ionization of a dilute gas target by an ultrashort pulse inside a femtosecond enhancement cavity. Numerical simulations detail how the dynamic ionization of the gas target limits the achievable peak intensity of the evolving intracavity pulse beyond that of linear cavity losses, setting a constraint on the strength of the nonlinear interaction that can be sustained in such optical cavities. Experimental measurements combined with numerical simulations predict ionization levels in a femtosecond enhancement cavity for the first time. We demonstrate how the resonant response of the femtosecond enhancement cavity can itself be used as a sensitive probe of optical nonlinearities at high intensities. 相似文献
175.
Lewis T. Wright 《Fresenius' Journal of Analytical Chemistry》1890,29(1):479
Ohne Zusammenfassung 相似文献
176.
The synthesis of alkyl-substituted 2-pyrrolecarboxylate esters has been accomplished by the condensation reaction of a symmetrical vinamidinium salt and glycine ester derivatives. 相似文献
177.
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179.
J. D. Maitland Wright 《Rendiconti del Circolo Matematico di Palermo》1923,47(3):465-480
Si sviluppano rappresentazioni di forme bilineari e sesquilineari tramite somme di prodotti di funzionali per una classe ampia di spazi di Banach, che include algebre di operatori e tripleJ B *. 相似文献
180.
C.R.A. Catlow M. Cherry K.H. Chow S.P. Cottrell S.F.J. Cox E.A. Davis K.V. Wright 《Hyperfine Interactions》1997,106(1-4):119-122
The expectation that the hydroxyl analogue state of positive muons implanted in quartz should be stabilized by a suitable
charge compensation centre is supported by preliminary data. The diamagnetic fraction correlates with aluminium content over
the narrow range investigated.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献