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Surgical strategies in paediatric inflammatory bowel disease

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World Journal of Gastroenterology 2015年第20期21卷 6101-6116页

作者： Colin t Baillie Jennifer A smith Department of Paediatric Surgery Royal Liverpool Childrens Hospital

Inflammatory bowel disease(IBD) comprises two distinct but related chronic relapsing inflammatory conditions affecting different parts of the gastrointestinal tract. Crohn's disease is characterised by a patchy transmural inflammation affecting both small and large bowel segments with several distinct phenotypic presentations. Ulcerative colitis classically presents as mucosal inflammation of the rectosigmoid(distal colitis), variably extending in a contiguous manner more proximally through the colon but not beyond the caecum(pancolitis). this article highlights aspects of the presentation, diagnosis, and management of IBD that have relevance for paediatric practice with particular emphasis on surgical considerations. Since 25% of IBD cases present in childhood or teenage years, the unique considerations and challenges of paediatric management should be widely appreciated. Conversely, we argue that the organizational separation of the paediatric and adult healthcare worlds has often resulted in late adoption of new approaches particularly in paediatric surgical practice.

关键词： Inflammatory bowel disease Ulcerativecolitis Crohn's disease Paediatric Surgery

Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion

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Neural Regeneration Research 2025年第4期20卷 1192-1206页

作者： tyler A.smith Liwen Zhou Cameron L.Ghergherehchi Michelle Mikesh Cathy Z.Yang Haley O.tucker JuliAnne Allgood Jared S.Bushman George D.Bittner Department of Molecular Biosciences University of Texas at AustinAustinTXUSA Department of Neuroscience University of Texas at AustinAustinTXUSA Division of Pharmaceutical Sciences University of WyomingLaramieWYUSA

Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal ***,such peripheral nerve allografts undergo immunological rejection by the host immune *** contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian *** relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this *** hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral *** examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal ***-type sciatic nerve injuries in outbred Sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host *** to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days *** morphological signs of rejection,such as col

关键词： allograft rejection axotomy macrophage myelin nerve repair polyethylene glycol(PEG) sciatic nerve t cell transplantation Wallerian degeneration

tEStS ON StRUCtURALLY DEFICIENt RC SLABS StRENGtHENED WItH FIBRE REINFORCED POLYMER (FRP) COMPOSItES

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工业建筑 2004年第Z1期34卷 -页

作者： S.t. smith Centre for Built Infrastructure Research Faculty of Engineering University of technology Sydney PO Box 123 Broadway NSW 2007 Australia

［1］Arduini, M., Nanni, A. and Romagnolo, M. (2004) "Performance of one-way reinforced concrete slabs with externally bonded fiber-reinforced polymer strengthening", ACI Structural Journal, Vol.101, No. 2, pp. 193-201.［2］AS 1012 Methods of testing Concrete, Standards Australia, Sydney, Australia.［3］AS1391 (1991)Methods for tensile testing of Metals, Standards Australia, Sydney, Australia.［4］AS3600 (2001) Concrete Structures, Standards Australia, Sydney, Australia.［5］AS/NZS4671 (2001) Steel Reinforcing Materials, Standards Australia, Sydney, Australia.［6］Lam, L. and teng, J.G. (2001) “Strength of RC cantilever slabs bonded with GFRP strips”,Journal of Composites for Construction, ASCE, Vol. 5, No. 4, pp. 221-227.［7］Seim, W., Horman, M. Karbhari, V. and Seible, F. (2001) “External FRP poststrengthening of scaled concrete slabs”, Journal of Composites for Construction, ASCE, Vol. 5, No. 2, pp. 67-75.［8］smith, S.t. and Gilbert, R.I. (2003) “tests on RC slabs reinforced with 500 MPa welded wire fabric”, Proceedings (CD-ROM), Concrete in the 3rd Millennium, CIA 2003, 21st Biennial Conference, Concrete Institute of Australia (CIA), Brisbane, Australia, 17-19 July.［9］teng, J.G., Lam, L, Chan, W. and Wang, J. (2000) “Retrofitting of deficient RC cantilever slabs using GFRP strips”, Journal of Composites for Construction, ASCE, Vol. 4, No. 2, pp. 75-84.［10］teng, J.G., Chen, J.F., smith, S.t. and Lam, L. (2002) FRP-Strengthened RC Structures, John Wiley & Sons, Chichester, West Sussex, U.K., 245 pp.［11］teng, J.G., smith, S.t., Yao, J. and Chen, J.F. (2003) “Intermediate crack induced debonding in RC beams and slabs”, Construction and Building Materials, Vol. 17, No. 6-7, pp.

关键词： steel reinforcement reinforced concrete reinforced polymer

Analysis and behaviour of FRP-confined short concrete columns subjected to eccentric loading

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 38-49页

作者： Xing-fei YUAN Shao-hua XIA L. LAM S.t. smith Department of Civil Engineering Zhejiang University Hangzhou 310027 China School of Civil and Environmental Engineering The University of Adelaide Adelaide SA 5005 Australia Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China Department of Civil Engineering Hong Kong University Hong Kong China

Fibre-reinforced polymer (FRP) composites were widely utilized in civil engineering structures as the retrofit of reinforced concrete (RC) columns. to design FRP jackets safely and economically, the behaviour of such columns should be predicted first. this paper is concerned with the analysis and behaviour of FRP-confined RC circular and rectangular short col- umns subjected to eccentric loading. A simple design-oriented stress-strain model for FRP-confined concrete in a section analysis was first proposed. the accuracy was then proved by two test data. Following that, a parametric study including amount of FRP confinement, FRP strain capacity, unconfined concrete strength and shape of column section is provided. Some conclusions were obtained at the end of the paper. the work here will provide a comprehensive understanding of the behaviour of FRP-confined concrete columns. the simplicity of the model also enables a simple equivalent stress block to be developed for direct use in practical design.

关键词： Column FRP confinement Stress-strain model Section analysis Strength Ductility

Effect of Pressure on Intermediate Valence States in Cerium Kondo Compounds

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Journal of Rare Earths 2004年第1期22卷 7-12页

作者： Oomi G Kagayama t smith J L Lacerda A H Kaji S Ohashi M Department of Physics Kyushu University Ropponmatsu Fukuoka 810-8560 Japan Department of Mechanical Engineering and Materials Sciences Kumamoto University Kumamoto 860-8555 Japan Materials Science and technology Los Alamos National Laboratory Los Alamos NM 87545 USA

Electrical resistance, thermal expansion, lattice constants of the intermediate valence materials, α-Ce and CeBe 13, were measured at high pressure. It is found that the Grüneisen parameters of Kondo temperature t K are 13 and 42 for α-Ce and CeBe 13, respectively, and it decreases with increasing pressure. the magnetoresistance of α-Ce shows H2 dependence and its coefficient increases with pressure below 1 GPa, but becomes nearly constant above 1 GPa. the results indicate that the intermediate valence states are enhanced at high pressure indicating the enhancement of hybridization between the 4f electron and conduction band.

关键词： condensel physics intermediate valence materials cerium rare earths

Functional-trait ecology of the plateau pika Ochotona curzoniae in the Qinghai-tibetan Plateau ecosystem

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Integrative Zoology 2019年第1期14卷 87-103页

作者： Andrew t.smith BADINGQIUYING Maxwell C.WILSON Brigitte W.HOGAN School of Life Sciences Arizona State UniversityTempeArizonaUSA School of Geographical Sciences Qinghai Normal UniversityXiningChina

Understanding a species’functional traits allows for a directed and productive perspective on the role a species plays in nature,and thus its relative importance to conservation *** functionaltrait ecology of the plateau pika Ochotona curzoniae is examined to better understand the resilience and sustainability of the high alpine grasslands of the Qinghai-tibetan Plateau(QtP).the key functional traits of plateau pikas are their abundance and behavior of digging extensive burrow *** pikas have been poisoned over a significant part of their original geographic distribution across the QtP,allowing comparison of ecological communities with and without *** all mammalian and avian carnivores,most of which are obligate predators on pikas,have been lost in regions where pikas have been *** endemic birds on the QtP nest in pika burrows;when pikas are poisoned,burrows collapse,and these birds are greatly reduced in *** to the biopedturbation resulting from their burrows,regional plant species richness is higher in areas with pikas than *** presence of pika burrows allows higher rates of infiltration during heavy monsoon rains compared to poisoned areas,possibly mitigating runoff and the potential for serious downslope erosion and ***,the functional traits of plateau pikas enhance native biodiversity and other important ecosystem functions;these traits are *** plateau pikas are not natural colonizers,active reintroduction programs are needed to restore pikas to areas from which they have been poisoned to restore the important functional ecological traits of pikas.

关键词： ecosystem engineer functional-trait ecology keystone species Ochotona curzoniae re-introduction

Age and sex specific timing, frequency, and spatial distribution of horseshoe crab spawning in Delaware Bay:Insights from a large-scale radio telemetry array

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Current Zoology 2010年第5期56卷 563-574页

作者： David R.smith Lorne J.BROUSSEAU Mary t. MANDt Michael J.MILLARD USGS Leetown Science Center Cornell University Cooperative Extension U.S. Fish and Wildlife Service

to study horseshoe crab Limulus polyphemus spawning behavior and migration over a large-spatial extent （〉100 km）, we arrayed fixed station radio receivers throughout Delaware Bay and deployed radio transmitters and archival tags on adult horseshoe crabs prior to their spawning season. We tagged and released 160 females and 60 males in 2004 and 217 females in 2005. the array covered approximately 140 km of shoreline. Recapture rates were 〉70% with multi-year recaptures. We categorized adult age by carapace wear. Older females tended to spawn earlier in the season and more frequently than young females, but those tendencies were more apparent in 2004 when spawning overall occurred earlier than in 2005 when spawning was delayed possibly due to decreased water temperatures. timing of initial spawning within a year was correlated with water temperature. After adjusting for day of first spring tide, the day of In＇st spawning was 4 days earlier for every 1 degree （℃） rise in mean daily water temperature in May. Seventy nine % of spawning occurred during nighttime high tides. Fifty five % of spawning occurred within 3 d of a spring tide, which was slightly higher than the 47% expected if spawning was uniformly distributed regardless of tidal cycle. Within the same spawning season, males and females were observed spawning or intertidally resting at more than one beach separated by 〉5 kin. Between years, most （77%） did not return to spawn at the same beach. Probability of stranding was strongly age dependent for males and females with older adults experiencing higher stranding rates. Horseshoe crabs staging in the shallow waters east of the channel spawned exclusively along the eastern （N J） shoreline, but those staging west of the channel spawned throughout the bay. Overall, several insights emerged from the use of radio telemetry, which advances our understanding of horseshoe crab ecology and will be useful in conserving the Delaware Bay horseshoe crab population and habita

关键词： Spawning behavior Marine arthropod Xiphosurid Limulus polyphemus Delaware Bay Radio telemetry

Impact of tillage and Fertilizer Application Method on Gas Emissions in a Corn Cropping System

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Pedosphere 2012年第5期22卷 604-615页

作者： K. smith D. WAttS t. WAY H. tORBERt S. PRIOR Department of Math Science and Technology University of Minnesota Crookston Crookston MN 56716 (USA) USDA-ARS National Soil Dynamics Laboratory 411 S. Donahue Dr. Auburn AL 36832 (USA)

tillage and fertilization practices used in row crop production are thought to alter greenhouse gas emissions from soil. this study was conducted to determine the impact of fertilizer sources, land management practices, and fertilizer placement methods on greenhouse gas （CO2, CH4, and N2O） emissions. A new prototype implement developed for applying poultry litter in subsurface bands in the soil was used in this study. the field site was located at the Sand Mountain Research and Extension Center in the Appalachian Plateau region of northeast Alabama, USA, on a Hartsells fine sandy loam （fine-loamy, siliceous, subactive, thermic typic Hapludults）. Measurements of carbon dioxide （CO2）, methane （CH4）, and nitrous oxide （N20） emissions followed GRACEnet （greenhouse gas reduction through agricultural carbon enhancement network） protocols to assess the effects of different tillage （conventional vs. no-tillage） and fertilizer placement （subsurface banding vs. surface application） practices in a corn （Zea mays L.） cropping system. Fertilizer sources were urea-ammonium nitrate （UAN）, ammonium nitrate （AN） and poultry litter （M） applied at a rate of 170 kg ha^（-1） of available N. Banding of fertilizer resulted in the greatest concentration of gaseous loss （CO2 and N2O） compared to surface applications of fertilizer. Fertilizer banding increased CO2 and N2O loss on various sampling days throughout the season with poultry litter banding emitting more gas than UAN banding. Conventional tillage practices also resulted in a higher concentration of CO2 and N2O loss when evaluating tillage by sampling day. throughout the course of this study, CH4 flux was not affected by tillage, fertilizer source, or fertilizer placement method. these results suggest that poultry litter use and banding practices have the potential to increase greenhouse gas emissions.

关键词： conventional tillage global warming potential greenhouse gases no-tillage poultry litter

Minimal conceptual models for tropical cyclone intensification

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tropical Cyclone Research and Review 2022年第2期11卷 61-75页

作者： Michael t.Montgomery Roger K.smith Department of Meteorology Naval Postgraduate SchoolMontereyCAUSA Meteorological Institute Ludwig-Maximilians UniversityMunichGermany

We examine a hierarchy of minimal conceptual models for tropical cyclone *** models are framed mostly in terms of axisymmetric balance *** the first set of models,the heating rate is prescribed in such a way to mimic a deep overturning circulation with convergence in the lower troposphere and divergence in the upper troposphere,characteristic of a region of deep moist *** the second set,the heating rate is related explicitly to the latent heat release of ascending air *** release of latent heat markedly reduces the local static stability of ascending air,raising two possibilities in the balance *** first possibility is that the effective static stability and the related discriminant in the Eliassen equation for the overturning circulation in saturated air,although small,remains positive so the Eliassen equation is globally *** second possibility,the more likely one during vortex intensification,is that the effective static stability in saturated air is negative and the Eliassen equation becomes locally *** models help to understand the differences between the early Ooyama models of 1968 and 1969,the Emanuel,1989 model,and the later Emanuel models of 1995,1997 and *** provide insight also into the popular explanation of the WISHE feedback mechanism for tropical cyclone *** implications for recent work are discussed.

关键词： tropical cyclone intensification Conventional spin-up mechanism Minimal models Nonlinear boundary layer spin-up mechanism WISHE feedback Mechanism