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Ileal pouch surgery for ulcerative colitis

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World journal of Gastroenterology 2007年第24期13卷 3288-3300页

作者： simon P Bach Neil j Mortensen Department of Colorectal Surgery John Radcliffe Hospital Oxford OX3 9DU United Kingdom

Ulcerative colitis (UC) is a relapsing and remitting disease characterised by chronic mucosal and submucosal inflammation of the colon and rectum. Treatment may vary depending upon the extent and severity of inflammation. Broadly speaking medical treatments aim to induce and then maintain remission. Surgery is indicated for inflammatory disease that is refractory to medical treatment or in cases of neoplastic transformation. Approximately 25% of patients with UC ultimately require colectomy. Ileal pouch-anal anastomosis (IPAA) has become the standard of care for patients with ulcerative colitis who ultimately require colectomy. This review will examine indications for IPAA, patient selection, technical aspects of surgery, management of complications and long term outcome following this procedure.

关键词： Ulcerative colitis Ileal Pouch Ileal pouch anal anastomosis

Nonlinear shear behavior of rock joints using a linearized implementation of the Barton-Bandis model

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journal of Rock Mechanics and Geotechnical Engineering 2017年第4期9卷 671-682页

作者： simon Heru Prassetyo Marte Gutierrez Nick Barton Department of Civil and Environmental Engineering Colorado School of Mines Golden CO 80401 USA Nick Barton and Associates Oslo Norway

Experiments on rock joint behaviors have shown that joint surface roughness is mobilized under shearing,inducing dilation and resulting in nonlinear joint shear strength and shear stress *** displacement *** Barton-Bandis(B-B) joint model provides the most realistic prediction for the nonlinear shear behavior of rock *** B-B model accounts for asperity roughness and strength through the joint roughness coefficient(jRC) and joint wall compressive strength(jCS) ***,many computer codes for rock engineering analysis still use the constant shear strength parameters from the linear Mohr-Coulomb(M-C) model,which is only appropriate for smooth and non-dilatant *** limitation prevents fractured rock models from capturing the nonlinearity of joint shear *** bridge the B-B and the M C models,this paper aims to provide a linearized implementation of the B-B model using a tangential technique to obtain the equivalent M-C parameters that can satisfy the nonlinear shear behavior of rock *** equivalent parameters,namely the equivalent peak cohesion,friction angle,and dilation angle,are then converted into their mobilized forms to account for the mobilization and degradation of jRC under *** conversion is done by expressing jRC in the equivalent peak parameters as functions of joint shear displacement using proposed hyperbolic and logarithmic functions at the pre-and post-peak regions of shear displacement,***,the pre-and post-peak joint shear stiffnesses are derived so that a complete shear stress-shear displacement relationship can be *** of the linearized implementation of the B-B model show that the shear stress-shear displacement curves,the dilation behavior,and the shear strength envelopes of rock joints are consistent with available experimental and numerical results.

关键词： Rock joints joint shear behavior Friction and dilation Barton-Bandis(B-B) model Equivalent Mohr-Coulomb(M-C) parameters

A simultaneous approach for integration of thermal energy storages in industrial processes using multiperiod heat integration

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Energy Storage and Saving 2022年第2期1卷 117-128页

作者： simon Möhren Christian Schäfer jörg Meyer Hartmut Krause SWK E2 Institute for Energy Technology and Energy Management Hochschule Niederrhein University of Applied ScienceKrefeld47805Germany Institute of Thermal Engineering TU Bergakademie FreibergFreiberg09599Germany

In times of increasing global warming,enormous efforts are required to rapidly reduce greenhouse gas(GHG)*** to the EU’s target of climate neutrality by 2050 and the even more ambitious goal of becoming climate-neutral in Germany by 2045,it is necessary to systematically increase energy efficiency and decarbonize the industrial heat *** methods of heat integration can be used to exploit existing potentials for waste heat utilization and to integrate renewable technologies for heating and *** using a non-stationary,multiperiod approach,additional energy savings can be achieved by integrating a thermal energy storage(TES)that enables heat transportation over *** paper presents a simultaneous approach for thermal energy storage integration into multiperiod heat integration *** approach can be used to minimize energy demand,costs and CO 2 emissions and is demonstrated in two case *** case study 1,it is shown that the presented approach is capable of integrating a TES properly into a simple multiperiod heat integration problem with two *** case study 2,a simplified example from a cosmetics manufactory is *** total utility demand can be reduced by up to 44.3%due to TES integration and the energetic optimal storage size can be determined as 125 m *** savings are strongly dependent on the constellation of heat flows between the periods,on the temperature levels and on the storage *** reductions of energy demand,costs and CO 2 emissions can be achieved with TES being properly integrated into a suitable operating environment.

关键词： Multiperiod heat integration Thermal energy storage Waste heat utilization Heat exchanger network Energy efficiency

Constrained fixed-fulcrum reverse shoulder arthroplasty improves functional outcome in epileptic patients with recurrent shoulder instability

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World journal of Orthopedics 2016年第7期7卷 434-441页

作者： Tanujan Thangarajah Deborah Higgs j I L Bayley simon M Lambert the Shoulder and Elbow Service the Royal National Orthopaedic Hospital

AIM: To report the results of fixed-fulcrum fully constrained reverse shoulder arthroplasty for the treatment of recurrent shoulder instability in patients with epilepsy. METHODS: A retrospective review was conducted at a single facility. Cases were identified using a com-puterized database and all clinic notes and operative reports were reviewed. All patients with epilepsy and recurrent shoulder instability were included for study. Between july 2003 and August 2011 five shoulders in five consecutive patients with epilepsy underwent fixed-fulcrum fully constrained reverse shoulder arthroplasty for recurrent anterior shoulder instability. The mean duration of epilepsy in the cohort was 21 years(range, 5-51) and all patients suffered from grand mal seizures. RESULTS: Mean age at the time of surgery was 47 years(range, 32-64). The cohort consisted of four males and one female. Mean follow-up was 4.7 years(range, 4.3-5 years). There were no further episodes of instability, and no further stabilisation or revision procedures were performed. The mean Oxford shoulder instability score improved from 8 preoperatively(range, 5-15) to 30 postoperatively(range, 16-37)(P = 0.015) and the mean subjective shoulder value improved from 20(range, 0-50) preoperatively to 60(range, 50-70) postoperatively(P = 0.016). Mean active forward elevation improved from 71° preoperatively(range,45°-130°) to 100° postoperatively(range, 80°-90°) and mean active external rotation improved from 15° preoperatively(range, 0°-30°) to 40°(20°-70°) postoperatively. No cases of scapular notching or loosening were noted. CONCLUSION: Fixed-fulcrum fully constrained reverse shoulder arthroplasty should be considered for the treatment of recurrent shoulder instability in patients with epilepsy.

关键词： Arthroplasty Dislocation Epilepsy Instability Shoulder

Effect of Small Addition of Sc on the Microstructural Evolution in Al-15Ag Alloy

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journal of Materials Science & Technology 2005年第5期21卷 630-634页

作者： Zhiguo CHEN Ziqiao ZHENG simon P.Ringer School of Materials Science and Engineering Central South University Changsha 410083 China Australian Key Centre for Microscopy & Microanalysis The University of Sydney 2006 NSW Australia

The effect of small addition of Sc on the microstructural evolution in Al-15Ag alloy was investigated by Monte Carlo simulation and transmission electron microscopy （TEM）. Monte Carlo simulation results indicate that Ag clustering is suppressed by the addition of Sc during the initial ageing stage, and there is a little chemical repulsion between Ag atoms and Sc atoms. TEM observations show that the morphology of γ′ precipitation can be modified by the small addition of Sc, which does result in a refinement of γ′ precipitates in Al-15Ag-0.2Sc. The mechanism by which trace Sc affect the microstructure is to reduce the ledge density of γ′precipitates.

关键词： Aluminium alloys Ageing Microstructure Scandium

Tracking the Cretaceous transcontinental Ceduna River through Australia:The hafnium isotope record of detrital zircons from offshore southern Australia

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Geoscience Frontiers 2016年第2期7卷 237-244页

作者： jarred Lloyd Alan S.Collins justin L.Payne Stijn Glorie simon Holford Anthony j.Reid Centre for Tectonics Resources and Exploration(TRaX)Department of Earth SciencesThe University of Adelaide Centre for Tectonics Resources and Exploration(TRaX)School of Built and Natural EnvironmentsThe University of South Australia Centre for Tectonics Resources and Exploration(TRaX)Australian School of PetroleumThe University of Adelaide Geological Survey of South Australia Department of State DevelopmentGovernment of South Australia

The middle-upper Cretaceous Ceduna River system traversed continental Australia from the NE coast to the centre of the southern coast. At its mouth, it formed a vast delta system that is similar in scale to the Niger delta of West Africa. The delta system is composed of two main lobes that represent different phases of delta construction. A recent hypothesis has challenged the traditional idea that both lobes of the delta were derived from a transcontinental river system by suggesting that the upper lobe （Santonian -Maastrichtian） is instead derived from a restricted catchment within southern Australia. Hf isotopic data presented here fingerprint the original source of the upper delta lobe zircons to NE Australia, with data comparing well with similar U-Pb and Lu-Hf isotopic data from the Lachlan Orogen, the New England Orogen, the eastern Musgraves Province and the northern Flinders Ranges. These data do not preclude a model where the lobe is derived from recycled Eromanga Basin sediments during a phase of late Cretaceous inland Australian uplift, but when coupled with reconnaissance low-temperature thermochronometry from the region of the Ceduna River course indicating widespread Triassic-jurassic exhumation, and comparisons with detrital zircon data from the Winton Formation upstream of any proposed uplift, we suggest that both lobes of the Ceduna Delta are likely to be derived from a transcontinental Ceduna River.

关键词： Detrital zircon Hf U-Pb Ceduna sub-basin Bight basin Australia

Recent advances in metasurface design and quantum optics applications with machine learning,physics-informed neural networks,and topology optimization methods

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Light(Science & Applications) 2023年第8期12卷 1494-1509页

作者： Wenye ji jin Chang He-Xiu Xu jian Rong Gao simon Groblacher H.Paul Urbach Aurele j.L.Adam Department of Imaging Physics Delft University of TechnologyLorentzweg 12628 CJ DelftThe Netherlands Department of Quantum Nanoscience Delft University of TechnologyLorentzweg 12628 CJ DelftThe Netherlands Shaanxi Key Laboratory of Flexible Electronics(KLoFE) Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'an 710072China SRON Netherlands Institute for Space Research Niels Bohrweg 42333 CA LeidenThe Netherlands

As a two-dimensional planar material with low depth profile,a metasurface can generate non-classical phase distributions for the transmitted and reflected electromagnetic waves at its ***,it offers more flexibility to control the wave front.A traditional metasurface design process mainly adopts the forward prediction algorithm,such as Finite Difference Time Domain,combined with manual parameter ***,such methods are time-consuming,and it is difficult to keep the practical meta-atom spectrum being consistent with the ideal *** addition,since the periodic boundary condition is used in the meta-atom design process,while the aperiodic condition is used in the array simulation,the coupling between neighboring meta-atoms leads to inevitable *** this review,representative intelligent methods for metasurface design are introduced and discussed,including machine learning,physics-information neural network,and topology optimization *** elaborate on the principle of each approach,analyze their advantages and limitations,and discuss their potential *** also summarize recent advances in enabled metasurfaces for quantum optics *** short,this paper highlights a promising direction for intelligent metasurface designs and applications for future quantum optics research and serves as an up-to-date reference for researchers in the metasurface and metamaterial fields.

关键词： optics quantum topology

Electrical control of quantum emitters in a Van der Waals heterostructure

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Light(Science & Applications) 2022年第8期11卷 1790-1798页

作者： simon j.U.White Tieshan Yang Nikolai Dontschuk Chi Li Zai-Quan Xu Mehran Kianinia Alastair Stacey Milos Toth Igor Aharonovich School of Mathematical and Physical Sciences University of Technology SydneyUltimoNSW2007Australia ARC Centre of Excellence for Transformative Meta-Optical Systems University of Technology SydneyUltimoNSW2007Australia School of Physics University of MelbourneParkvilleVIC3010Australia School of Science RMIT UniversityMelbourneVIC3001Australia

Controlling and manipulating individual quantum systems in solids underpins the growing interest in the development of scalable quantum ***,hexagonal boron nitride(hBN)has garnered significant attention in quantum photonic applications due to its ability to host optically stable quantum ***,the large bandgap of hBN and the lack of efficient doping inhibits electrical triggering and limits opportunities to study the electrical control of ***,we show an approach to electrically modulate quantum emitters in an hBN-graphene van der Waals *** show that quantum emitters in hBN can be reversibly activated and modulated by applying a bias across the ***,a significant number of quantum emitters are intrinsically dark and become optically active at non-zero *** explain the results,we provide a heuristic electrostatic model of this unique ***,employing these devices we demonstrate a nearly-coherent source with linewidths of~160 *** results enhance the potential of hBN for tunable solid-state quantum emitters for the growing field of quantum information science.

关键词： quantum hexagonal boron

Evaluation of the ability of arsenic species to traverse cell membranes by simple diffusion using octanol-water and liposome-water partition coefficients

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journal of Environmental Sciences 2016年第11期28卷 222-232页

作者： Teresa Chavez-Capilla William Maher Tamsin Kelly simon Foster Ecochemistry Laboratory Institute for Applied Ecology University of Canberra Canberra ACT 2601 Australia National Centre for Forensic Studies Faculty of Education Science Technology and Mathematics University of Canberra CanberraACT 2601 Australia

Arsenic metabolism in living organisms is dependent on the ability of different arsenic species to traverse biological membranes. Simple diffusion provides an alternative influx and efflux route to mediated transport mechanisms that can increase the amount of arsenic available for metabolism in cells. Using octanol-water and liposome-water partition coefficients, the ability of arsenous acid, arsenate, methylarsonate, dimethylarsinate, thio-methylarsonate, thiodimethylarsinic acid, arsenotriglutathione and monomethylarsonic diglutathione to diffuse through the lipid bilayer of cell membranes was investigated. Molecular modelling of arsenic species was used to explain the results. All arsenic species with the exception of arsenate, methylarsonate and thio-methylarsonate were able to diffuse through the lipid bilayer of liposomes, with liposome-water partition coefficients between 0.04 and 0.13. Trivalent arsenic species and thio-pentavalent arsenic species showed higher partition coefficients, suggesting that they can easily traverse cell membranes by passive simple diffusion. Given the higher toxicity of these species compared to oxo-pentavalent arsenic species, this study provides evidence supporting the risk associated with human exposure to trivalent and thio-arsenic species.

关键词： ArsenicLiposomesPartition coefficientsPassive simple diffusionTrivalent arsenic speciesThio-arsenic species