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Acta Mathematica Scientia 2011年第6期31卷 2343-2377页

作者： jeffery C. diFranco Peter d. Miller Benson K. Muite department of Mathematics Seattle University department of Mathematics University of Michigan

The purpose of this paper is to present a comparison between the modified nonlinear SchrSdinger （MNLS） equation and the focusing and defocusing variants of the （unmodified） nonlinear SchrSdinger （NLS） equation in the semiclassical limit. We describe aspects of the limiting dynamics and discuss how the nature of the dynamics is evident theoretically through inverse-scattering and noncommutative steepest descent methods. The main message is that, depending on initial data, the MNLS equation can behave either like the defocusing NLS equation, like the focusing NLS equation （in both cases the analogy is asymptotically accurate in the semiclassical limit when the NLS equation is posed with appropriately modified initial data）, or like an interesting mixture of the two. In the latter case, we identify a feature of the dynamics analogous to a sonic line in gas dynamics, a free boundary separating subsonic flow from supersonic flow.

关键词： semiclassical limits dispersionless limits modulational instability focusing,defocusing, and modified nonlinear SchrSdinger equations

Results of single stage exchange arthroplasty with retention of well fixed cement-less femoral component in management of infected total hip arthroplasty

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World Journal of Orthopedics 2017年第3期8卷 264-270页

作者： Wael A Rahman Hussain A Kazi jeffery d Gollish Orthopaedic department Mansoura University Holland Orthopaedic and Arthritic Centre Sunnybrook Health Sciences Centre Mid Cheshire Hospitals NHS Foundation Trust Leighton Hospital

AIM To investigate success of one stage exchange with retention of fixed acetabular *** Fifteen patients treated by single stage acetabular component exchange with retention of well-fixed femoral component in infected total hip arthroplasty(THA)were retrospectively *** criteria were patients with painful chronic infected total *** patient had radiologically well fixed femoral components,absence of major soft tissue or bone defect compromising,and infecting organism was not poly or virulent *** organisms were identified preoperatively in14 patients(93.3%),coagulase negative Staphylococcus was the infecting organism in 8 patients(53.3%).RESULTS Mean age of the patients at surgery was 58.93(±10.67)*** follow-up was 102.8 mo(36-217 mo,Sd56.4).Fourteen patients had no recurrence of the infection;one hip(6.7%)was revised for management of *** analysis using Kaplan Meier curve showed 93.3%survival *** failure in our series;the infection recurred after 14 mo,the patient was treated successfully with surgical intervention by irrigation,and debridement and liner *** complications:The first patient had recurrent hip dislocation 12 years following the definitive procedure,which was managed by revision THA with abductor reconstruction and constrained acetabular liner;the second complication was aseptic loosening of the acetabular component 2years following the definitive *** Successful in management of infected THA when following criteria are met;well-fixed stem,no draining sinuses,non-immune compromised patients,and infection with sensitive organisms.

关键词： Total hip arthroplasty Infection One stage exchange Complication

A study of process-induced grain structures during steady state and non-steady state electron-beam welding of a titanium alloy

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Journal of Materials Science & Technology 2022年第18期113卷 117-127页

作者： Yu Lu Richard Turner jeffery Brooks Hector Basoalto School of Metallurgy and Materials University of BirminghamBirminghamB152TTUnited Kingdom department of Materials Science and Engineering The University of SheffieldMappin StreetSheffieldS13JDUnited Kingdom

A detailed microstructural characterisation of the emerging weld-line grain structure,for bead-upon-plate welds in Ti-6Al-4V(Ti64)of differing plate thickness,was *** microstructure studied was formed during both steady state and non-steady state sections within the weld path,with the non-steady state portion being taken from the end of the plate as the weld bead and heat source overhang the edge of the *** allows for the effects of welding process conditions on the microstructural evolution to be *** weld pool geometry and 3d tomography of the weld-induced defects have been *** characterisation of microstructure and texture for different welding parameters and for steady and non-steady states have been used to identify physical parameters for the microstructure predictions that are difficult to obtain *** different states significantly affect the weld crown shape and formation,weld toe,weld bead depth and ***,the heat affected zone(HAZ)re-mains *** the microstructural evolution,both the steady and non-steady states have similar microstructure and *** defects were observed in the steady state section of welds,but sub-surface spherical pores have been observed in the non-steady state section of a *** element modelling to simulate the thermal-metallurgical-mechanical fields within the steady and non-steady state sections of the welds was considered,and the cooling rates predicted within steady state and non-steady sections were interrogated to improve the theoretical understanding of the microstructure and defect formation differences in these Ti64 EB weld regions.

关键词： Electron-beam fusion welding Processing Microstructure Ti-6Al-4V

Intra-axonal protein synthesis–a new target for neural repair?

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Neural Regeneration Research 2016年第9期11卷 1365-1367页

作者： jeffery L.Twiss Ashley L.Kalinski Rahul Sachdeva John d.Houle department of Biological Sciences University of South Carolina department of Neurobiology and Anatomy Drexel University College of Medicine

Although initially argued to be a feature of immature neurons with incomplete polarization, there is clear evidence that neurons in the peripheral nervous system retain the capacity for intra-axonal protein synthe- sis well into adulthood. This localized protein synthesis has been shown to contribute to injury signaling and axon regeneration in peripheral nerves. Recent works point to potential for protein synthesis in axons of the vertebrate central nervous system, mRNAs and protein synthesis machinery have now been docu- mented in lamprey, mouse, and rat spinal cord axons. Intra-axonal protein synthesis appears to be activated in adult vertebrate spinal cord axons when they are regeneration-competent. Rat spinal cord axons regen- erating into a peripheral nerve graft contain mRNAs and markers of activated translational machinery. Indeed, levels of some growth-associated mRNAs in these spinal cord axons are comparable to the regen- erating sciatic nerve. Markers of active translation tend to decrease when these axons stop growing, but can be reactivated by a second axotomy. These emerging observations raise the possibility that mRNA transport into and translation within axons could be targeted to facilitate regeneration in both the peripheral and central nervous systems.

关键词： mRNA transport translational control RNA binding protein axon regeneration spinal cord injury peripheral nerve injury

The double helium-white dwarf channel for the formation of AM CVn binaries

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Research in Astronomy and Astrophysics 2018年第1期18卷 101-112页

作者： Xian-Fei Zhang Jin-Zhong Liu C.Simon jeffery Philip d.Hall Shao-Lan Bi department of Astronomy Beijing Normal University Xinjiang Astronomical Observatory Chinese Academy of Sciences Armagh Observatory and Planetarium College Hill School of Physics Trinity College Dublin

Most close double helium white dwarfs will merge within a Hubble time due to orbital decay by gravitational wave ***,a significant fraction with low mass ratios will survive for a long time as a consequence of stable mass *** stable mass transfer between two helium white dwarfs（He Wds） provides one channel for the production of AM CVn binary *** previous calculations of double He Wd progenitors,the accreting He Wd was treated as a point *** have computed the evolution of 16 double He Wd models in order to investigate the consequences of treating the evolution of both components in *** find that the boundary between binaries having stable and unstable mass transfer is slightly modified by this *** comparing with observed periods and mass ratios,we redetermine masses of eight known AM CVn stars by our double He Wds channel,*** Cnc,AM CVn,V406 Hya,J0926,J1240,GP Com,Gaia14 aae and V396 *** propose that central spikes in the triple-peaked emission spectra of J1240,GP Com and V396 Hya and the surface abundance ratios of N/C/O in GP Com can be explained by the stable double He Wd *** mass estimates derived from our calculations are used to discuss the predicted gravitational wave signal in the context of the Laser Interferometer Space Antenna（LISA） project.

关键词： stars:peculiar(helium) stars:white dwarfs binaries:close gravitational waves

Species distribution modeling in regions of high need and limited data： waterfowl of China

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Avian Research 2018年第1期9卷 49-62页

作者： diann J.Prosser Changqing ding R.Michael Erwin Taej Mundkur jeffery d.sulliva. Erle C.Ellis Patuxent Wildlife Research Center U.S. Geological Survey Beltsville MD 20705 USA University of Maryland College Park MD 20742 USA College of Nature Conservation Beijing Forestry University Beijing 100083 China University of Virginia Charlottesville VA 22904 USA Wetlands International Horapark9 Ede 6717 LZ The Netherlands Natural Systems Analysts Winter Park FL 32789 USA department of Geography and Environmental Systems University of Maryland Baltimore County Baltimore MD 21250 USA

Background: A number of conservation and societal issues require understanding how species are distributed on the landscape, yet ecologists are often faced with a lack of data to develop models at the resolution and extent desired, resulting in inefficient use of conservation *** a situation presented itself in our attempt to develop waterfowl distribution models as part of a multi-disciplinary team targeting the control of the highly pathogenic H5N1 avian influenza virus in ***: Faced with limited data, we built species distribution models using a habitat suitability approach for China's breeding and non-breeding(hereafter, wintering) *** extensive review of the literature was used to determine model parameters for habitat *** relationships were implemented in GIS using land cover *** models were validated using waterfowl census data, while breeding models, though developed for many species, were only validated for the one species with sufficient telemetry data ***: We developed suitability models for 42 waterfowl species(30 breeding and 39 wintering) at 1 km resolution for the extent of China, along with cumulative and genus level species richness *** season models showed highest waterfowl suitability in wetlands of the high-elevation west-central plateau and northeastern *** waterfowl suitability was highest in the lowland regions of southeastern *** measures indicated strong performance in predicting species *** our model outputs to China's protected areas indicated that breeding habitat was generally better covered than wintering habitat, and identified locations for which additional research and protection should be ***: These suitability models are the first available for many of China's waterfowl species, and have direct utility to conservation and habitat planning and prioritizing management of critically important

关键词： Anatidae Avian influenza China Habitat suitability H5N1 Spatial analysis Species distribution models Waterfowl

Associations between near work, outdoor activity, parental myopia and myopia among school children in Aba, Nigeria

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International Journal of Ophthalmology(English edition) 2020年第2期13卷 309-316页

作者： Uchenna Chigozirim Atowa Samuel Otabor Wajuihian Alvin jeffery Munsamy discipline of Optometry University of KwaZulu-NatalDurban 4000South Africa

●AIM:To assess the influence of near work,time outdoor and parental myopia on the prevalence of myopia in school children in Aba,Nigeria.●METHOdS:Primary and secondary school children aged between 8 and 15 y were randomly recruited from 12 schools in *** on family history,near work and outdoor activity was obtained using myopia risk factor *** refraction was performed using autorefraction *** was defined as spherical equivalent refraction(SER)≤-0.50 d in the poorer *** were analysed for 1197(male:538 and female:659)children with full relevant data.●RESULTS:Risk of developing myopia was positively associated with parental myopia[odds ratio(OR):6.80;95%CI,2.76-16.74;Pd(OR:9.47;95%CI,3.88-23.13;Pdaily reading hour(OR:1.21;95%CI,1.03-1.42;P=0.02)and less time outdoors(OR:0.8;95%CI,0.74-0.87;Pd with *** addition,children with both parents being myopic has increased odds of developing myopia than those with one myopic *** is recommended therefore,that children spend more time outdoors as this could reduce the prevalence and progression of myopia.

关键词： myopia near work parental myopia outdoor activity school children

Hybrid energy module for remote environmental observations, experiments, and communications

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Advances in Polar Science 2020年第3期31卷 156-166页

作者： Misha B.KRASSOVSKI jeffery S.RIGGS Chris TAVINO Stan d.WULLSCHLEGER Susan L.HEINZ Environmental Sciences division Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTN 37831-6290USA Integrated Operations Support division Oak Ridge National LaboratoryOak RidgeTN 37831-6290USA Laboratory Modernization division Oak Ridge National LaboratoryOak RidgeTN 37831-6290USA

Increased concerns about climate change have led to a significant expansion of monitoring, observational, and experimental sites in remote areas of the world. Meanwhile, advances in technology and availability of low-power equipment have allowed increasingly sophisticated measurements with a wide variety of instruments. However, the deployment and use of these technologies in remote locations is often restricted not only by harsh environmental conditions, but also by the availability of electrical power and communication options. In some cases, research stations and military installations can provide power for scientific equipment, data acquisition, storage, and transmission. Clustering of research sites near existing infrastructure has had the unintended consequence of limiting a spatial understanding of large geographic regions. Fortunately, the modern market offers many power and communication solutions, but most of them are oriented toward large industrial applications. Use of those solutions to power a research site is limited because of their cost and need for significant modification for the specific research purposes. Each study has its own unique power requirements and needs for proper instrumentation. A power and communication solution for a vast majority of implementations with or without modification would be of considerable benefit. This article describes design of a universal, scalable hybrid energy module for the Next-Generation Ecosystem Experiments Arctic project(https://***/). Two modules were built, and the authors describe their implementation and findings over a 2-year period at a remote field site on the Seward Peninsula in western Alaska, USA.

关键词： solar energy wind energy communications power sources alternative energy NGEE Arctic

Studies on the cytocompatibility,mechanical and antimicrobial properties of 3d printed poly(methyl methacrylate)beads

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Bioactive Materials 2018年第2期3卷 157-166页

作者： david K.Mills Uday Jammalamadaka Karthik Tappa jeffery Weisman Center for Biomedical Engineering and Rehabilitation Science USA The School of Biological Sciences Louisiana Tech UniversityRustonLA 71272USA

Osteomyelitis is typically a bacterial infection(usually from Staphylococcus)or,more rarely,a fungal infection of the *** can occur in any bone in the body,but it most often affects the long bones(leg and arm),vertebral(spine),and bones of the *** success in osteomyelitis is due to their ability to form biofilms which inhibit the wound healing process and increases resistance to anti-infective ***,biofilms do not allow easy penetration of antibiotics into their matrix making clinical treatment a *** development of local antibiotic delivery systems that deliver high concentrations of antibiotics to the affected site is an emerging area of research with great *** treatment includes antibiotic therapy,either locally or systemically and refractory cases of osteomyelitis may lead to surgical intervention and a prolonged course of antibiotic treatment involving placement of antibiotic-doped beads or spacers within the wound *** are disadvantages with this treatment modality including insufficient mixing of the antibiotic,lack of uniform bead size,resulting in lower antibiotic availability,and limitations on the antibiotics ***,a method is needed to address biofilm formations in the wound and on the surface of the surgical implants to prevent *** this study,we show that all antibiotics studied were successfully doped into PMMA and antibiotic-doped 3d printed beads,disks,and filaments were easily *** growth inhibition capacity of the antibiotic-loaded PMMA 3d printed constructs was also demonstrated.

关键词： 3d printing Antibacterials drug delivery Halloysite nanotubes Medical devices Nanotechnology

A New Species of Japalura(Squamata, Agamidae) from the Nu River Valley in Southern Hengduan Mountains, Yunnan, China

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Asian Herpetological Research 2017年第2期18卷 86-95页

作者： dingqi RAO Jens V.VINdUM Xiaohui MA Mingxia FU jeffery A.WILKINSON Kunming Institute of Zoology Chinese Academy of Sciences department of Herpetology California Academy of Sciences

A population of Japalura from Yunnan Province, China, previously assigned to Japalura splendida, is described as a new species. The new species has been recorded between 1 138–2 500 m in the Nu River drainage between the towns of Liuku and Binzhongluo, and on the lower western slopes of the Nushan and eastern slopes of the Goaligongshan. The new species can be distinguished from other species of Japalura, except J. dymondi, by the following combination of characters： exposed tympani, prominent dorso-lateral stripes, and small gular scales. It is very similar with but differs from J. dymondi by having smooth or feebly keeled dorsal head scales, three relatively enlarged spines on either side of the post-occiput area, strongly keeled and mucronate scales on occiput area and within the lateral stripes, back of arm and leg green, higher number of dorsal-ridge scales（dS） and fourth toe subdigital scales（T4S）. A principal component analysis of body measurements of adult male specimens of the new species and J. dymondi showed principal component 1 loading highest for upper arm length, fourth toe length and snout to eye length and principal component 2 loading highest for head width, head length and fourth toe length.

关键词： Agamidae Japalura sp.nov. Goaligongshan Mountain Nujiang River Valley Hengduan Mountains Yunnan China