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白沙蒿粘液瘦果萌发中外切糖苷酶活动特性(英文)

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Acta Botanica Sinica 2002年第11期44卷 1380-1383页

作者：黄振英 Daphne J.osborne 中国科学院植物研究所植被数量生态学开放研究实验室北京100093 Oxford Research Unit

白沙蒿 (ArtemisiasphaerocephalaKrasch .)是中国西北沙区分布的多年生植物。瘦果遇湿后其粘液层开始膨胀。对其种子萌发不同阶段的种胚提取物中几种可能降解果皮外层粘液物质的外切糖苷酶进行了检测。结果表明 :β 吡喃半乳糖苷酶在... 详细信息

白沙蒿 (ArtemisiasphaerocephalaKrasch .)是中国西北沙区分布的多年生植物。瘦果遇湿后其粘液层开始膨胀。对其种子萌发不同阶段的种胚提取物中几种可能降解果皮外层粘液物质的外切糖苷酶进行了检测。结果表明 :β 吡喃半乳糖苷酶在干种子中的活性很高 ,但是随着种子的吸涨而逐渐降低 ,在已萌发的种子中无法探测到。α和 β 吡喃阿拉伯糖苷酶、β 吡喃葡萄糖苷酶以及 β 吡喃甘露糖苷酶在种子萌发过程的胚提取物中也显示出了一些活性 ,但是这些活性在种胚外却无法探测到。所有胚提取物中的外切糖苷酶都无法降解果皮粘液物质。所有的证据都表明果皮外层的粘液物质无法在种子萌发的早期被水解。因此果皮粘液物质在干旱沙质条件下的生态功能被限制在吸收水分以及延长胚吸水的时间。

关键词：白沙蒿粘液瘦果萌发外切糖苷酶活动特性生态功能沙区先锋植物干旱

THE NAVIER-STOKES EQUATIONS WITH THE KINEMATIc AND VORTIcITY BOUNDARY cONDITIONS ON NON-FLAT BOUNDARIES

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Acta Mathematica Scientia 2009年第4期29卷 919-948页

作者： Dan osborne Mathematical Institute University of Oxford 24-29 St Giles

We study the initial-boundary value problem of the Navier-Stokes equations for incompressible fluids in a general domain in R^n with compact and smooth boundary, subject to the kinematic and vorticity boundary conditions on the non-flat boundary. We observe that, under the nonhomogeneous boundary conditions, the pressure p can be still recovered by solving the Neumann problem for the Poisson equation. Then we establish the well-posedness of the unsteady Stokes equations and employ the solution to reduce our initial-boundary value problem into an initial-boundary value problem with absolute boundary conditions. Based on this, we first establish the well-posedness for an appropriate local linearized problem with the absolute boundary conditions and the initial condition （without the incompressibility condition）, which establishes a velocity mapping. Then we develop apriori estimates for the velocity mapping, especially involving the Sobolev norm for the time-derivative of the mapping to deal with the complicated boundary conditions, which leads to the existence of the fixed point of the mapping and the existence of solutions to our initial-boundary value problem. Finally, we establish that, when the viscosity coefficient tends zero, the strong solutions of the initial-boundary value problem in R^n（n ≥ 3） with nonhomogeneous vorticity boundary condition converge in L^2 to the corresponding Euler equations satisfying the kinematic condition.

关键词： Navier-Stokes equations incompressible vorticity boundary condition kinematic boundary condition absolute boundary condition non-flat boundary general domain Stokes operator Neumann problem Poisson equation vorticity strong solutions inviscid limit slip boundary condition

The evolution of sinus surgery in England in the last decade - An observational study

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2021年第3期7卷 240-246页

作者： Keshav Kumar Gupta Karan Jolly Navdeep Bhamra Max Sallis osborne Shahzada Khuram Ahmed Department of Otolaryngology New Cross HospitalThe Royal Wolverhampton NHS TrustWolverhamptonWV100QPUnited Kingdom Department of Otolaryngology Queen Elizabeth HospitalUniversity Hospitals Birmingham NHS Foundation TrustBirminghamB152THUnited Kingdom

Background and objective::Sinus surgery has seen significant changes over the years with advancements in instruments,endoscopes and *** study aimed to use Hospital Episode Statistics(HES)data to review the total number of sinus related procedures performed in both adults and children across England and identify whether there were any trends across the study *** predicted an increase in endoscopic sinus procedures with a decline in open approaches to the paranasal ***::Data from HES was extracted for the years *** operative(OPcS-4)codes relevant to all sinus procedures between E12.1 and E17.9 were *** examination of overall sinus related procedures,further subgroup analysis was performed with regards to open or endoscopic ***::The total number of sinus procedures performed between 2010 and 2019 was 89,*** was an increase in endoscopic surgeries by 21.1%and a decrease of open surgeries 35.3%during this *** was an overall increase in maxillary,frontal and sphenoid sinus procedures,with a decrease in ethmoid sinus and lateral rhinotomy *** was an increase in the proportion of endoscopic cases overall by 5.7%and for all sinuses ***::Overall,we see an increase in sinus surgery over the last 9 years from 2010 to *** findings are in keeping with our initial *** our data set is limited by coding,and lack of patient factors,it represents most,if not all,of the data in England over a large study *** is therefore useful to add to previous studies when demonstrating the increasing popularity of endoscopic sinus surgery over open procedures.

关键词： Endoscopic sinus surgery Sphenoid Ethmoid Frontal Maxillary Sinus

Biomolecular hydration dynamics probed with 2D-IR spectroscopy:From dilute solution to a macromolecular crowd

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chinese chemical Letters 2015年第4期26卷 435-438页

作者： John T.King Evan J.Arthur Derek G.osborne charles L.Brooks Ⅲ Kevin J.Kubarych Department of chemistry University of Michigan LSA Biophysics University of Michigan Department of Materials Science and Engineering University of Illinois

Although it is well known that water is essential for biological function, it has been a challenge to determine how water behaves near biomacromolecular interfaces, and what role water plays in influencing the dynamics of the biochemical machinery. By adopting a vibrational labeling strategy coupled with ultrafast two-dimensional infrared （2D-IR） spectroscopy, it has recently become possible to study hydration dynamics, site specifically at the surface of proteins and model membranes. We review our recent progress in measuring hydration dynamics in contexts ranging from small-molecule solutes to biomacromolecules in dilute, viscous, and crowded environments.

关键词： Protein hydration dynamicsMembrane dynamicsUltrafast infrared spectroscopy

Internationalization and strategic planning in universities

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Internationalization and strategic planning in universities

Evaluation of nutrient stoichiometric relationships among ecosystem compartments of a subtropical treatment wetland. Do we have “Redfield wetlands”?

北京论坛（2006）文明的和谐与共同繁荣—对人类文明方式的思考

作者： Michael osborne La Trobe University

The term’internationalization’means different things to different ***, especially in some western countries,it has come to be virtually synonymous with the export of higher education and training services(*** recrui...

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Ecological Processes 2019年第1期8卷 267-287页

作者： Paul Julian II Stefan Gerber Rupesh K.Bhomia Jill King Todd Z.osborne Alan L.Wright Matthew Powers Jacob Dombrowski Soil and Water Sciences Department University of FloridaFt.PierceFL34945USA Soil and Water Sciences Department University of FloridaGainesvilleFL 32611USA South Florida Water Management District Water Quality Treatment TechnologiesWest Palm BeachFL 33406USA Whitney Laboratory for Marine Bioscience University of FloridaSt AugustineFL 32080USA.

Background:Evaluation of carbon(c),nitrogen(N),and phosphorus(P)ratios in aquatic and terrestrial ecosystems can advance our understanding of biological processes,nutrient cycling,and the fate of organic matter(OM)in these *** of aquatic ecosystems can change the accumulation and decomposition of OM which can alter biogeochemical cycling and alter the base of the aquatic food *** study investigated nutrient stoichiometry within and among wetland ecosystem compartments(i.e.,water column,flocculent,soil,and aboveground vegetation biomass)of two subtropical treatment wetlands with distinct vegetation *** flow-ways(FWs)within the network of Everglades Stormwater Treatment Areas in south Florida(USA)were selected for this *** evaluated nutrient stoichiometry of these to understand biogeochemical cycling and controls of nutrient removal in a treatment wetland within an ecological stoichiometry ***:This study demonstrates that c,N,and P stoichiometry can be highly variable among ecosystem compartments and between *** law slopes of c,N,and P within surface water floc,soil,and vegetation were significantly different between and along ***:Assessment of wetland nutrient stoichiometry between and within ecosystem compartments suggests unconstrained stoichiometry related to P that conforms with the notion of P limitation in the *** in N:P ratios between floc and soil suggest different pathways of organic nutrient accumulation and retention between *** nutrient stoichiometry was highly variable and decoupled(or close to decoupled as indicated bycular with respect to *** hypothesize that decoupling may be the imprint of variability in inflow nutrient ***,despite active biogeochemical cycles that could act to restore nutrient stoichiometry along the FW,there was little evidence that such balancing occurred,as the

关键词： Decomposition Mineralization Everglades Treatment wetlands

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节能的现代热风炉

节能的现代热风炉

A Bayesian Inference Approach to Reduce Uncertainty in Magnetotelluric Inversion: A Synthetic case Study

中国金属学会2003中国钢铁年会

作者： David osborne 奥钢联工业(英国)有限公司

本篇论文讨论了新建和改造热风炉的现代设计,包括改善热风炉温度、炉容、炉役等,并且还论述了现代内部和外部燃烧室热风炉的典型生产参数。也考虑了热风炉和高炉在单位能源消耗上降低的可能性。考虑了不同大小的高炉,其热风炉的选择有... 详细信息

本篇论文讨论了新建和改造热风炉的现代设计,包括改善热风炉温度、炉容、炉役等,并且还论述了现代内部和外部燃烧室热风炉的典型生产参数。也考虑了热风炉和高炉在单位能源消耗上降低的可能性。考虑了不同大小的高炉,其热风炉的选择有所不同,并且还讨论了提高废热的回收效果。

关键词：现代热风炉热风温度耐材设计陶瓷喷嘴降低的能源消耗废热回收

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Journal of Geoscience and Environment Protection 2019年第2期7卷 62-75页

作者： osborne Kachaje Liangjun Yan Zhou Zhang School of Geophysics Yangtze University Wuhan China Key Laboratory of Exploration Technologies for Oil and Gas Resources Yangtze University Wuhan China Depertment of Physics and Biochemical Sciences University of Malawi Blantyre Malawi State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China college of Earth and Planetary Sciences University of Chinese Academy of Sciences Beijing China

The deterministic geophysical inversion methods are dominant when inverting magnetotelluric data whereby its results largely depends on the assumed initial model and only a single representative solution is obtained. A common problem to this approach is that all inversion techniques suffer from non-uniqueness since all model solutions are subjected to errors, under-determination and uncertainty. A statistical approach in nature is a possible solution to this problem as it can provide extensive information about unknown parameters. In this paper, we developed a 1D Bayesian inversion code based Metropolis-Hastings algorithm whereby the uncertainty of the earth model parameters were quantified by examining the posterior model distribution. As a test, we applied the inversion algorithm to synthetic model data obtained from available literature based on a three layer model (K, H, A and Q). The frequency for the magnetotelluric impedance data was generated from 0.01 to 100 Hz. A 5% Gaussian noise was added at each frequency in order to simulate errors to the synthetic results. The developed algorithm has been successfully applied to all types of models and results obtained have demonstrated a good compatibility with the initial synthetic model data.

关键词： Bayesian Inversion Magnetotellurics McMc Metropolis-Hastings Uncertainty