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Acute upper gastrointestinal bleeding in patients on long-term oral anticoagulation therapy: Endoscopic findings, clinical management and outcome

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World journal of Gastroenterology 2005年第9期11卷 1365-1368页

作者： Konstantinos C Thomopoulos Konstantinos p Mimidis George j Theocharis Anthie G Gatopoulou Georgios n Kartalis Vassiliki n nikolopoulou Department of Internal Medicine the First Department of Internal Medicine

AIM: Acute gastrointestinal bleeding is a severe complication in patients receiving long-term oral anticoagulant therapy. The purpose of this study was to describe the causes and clinical outcome of these patients. METHODS: From january 1999 to October 2003, 111 patients with acute upper gastrointestinal bleeding (AUGIB) were hospitalized while on oral anticoagulants. The causes and clinical outcome of these patients were compared with those of 604 patients hospitalized during 2000-2001 with AUGIB who were not taking warfarin. RESULTS: The most common cause of bleeding was peptic ulcer in 51 patients (45%) receiving anticoagulants compared to 359/604 (59.4%) patients not receiving warfarin (pno identifiable source of bleeding could be found in 33 patients (29.7%) compared to 31/604 (5.1%) patients not receiving anticoagulants (p=0.0001). The majority of patients with concurrent use of non-steroidal anti-inflammatory drugs (nSAIDs) (26/35, 74.3%) had a peptic ulcer as a cause of bleeding while 32/76 (40.8%) patients not taking a great dose of nSAIDs had a negative upper and lower gastrointestinal endoscopy. Endoscopic hemostasis was applied and no complication was reported. Six patients (5.4%) were operated due to continuing or recurrent hemorrhage, compared to 23/604 (3.8%) patients not receiving anticoagulants. Four patients died, the overall mortality was 3.6% in patients with AUGIB due to anticoagulants, which was not different from that in patients not receiving anticoagulant therapy. COnCLUSIOn: patients with AUGIB while on long-term anticoagulant therapy had a clinical outcome, which is not different from that of patients not taking anticoagulants. Early endoscopy is important for the management of these patients and endoscopic hemostasis can be safely applied.

关键词： AUGIB Anticoagulant therapy Endoscopy

Internal valves in populations of Meridion circulare from the A’er Mountain region of northeastern China:Implications for taxonomy and systematics

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journal of Systematics and Evolution 2011年第5期49卷 486-494页

作者： j.p.KOCIOLEK Department of Ecology and Evolutionary Biology University of Colorado Museum of natural History University of Colorado

A population of Meridion circulare ***(Greville) *** from Inner Mongolia was found to produce Innenschalen or internal *** of this population with light and scanning electron microscopy showed morphological differentiation between vegetative and spore *** valves typically bear costae and one rimoportula at the *** lack costae and have two rimoportulae,one at the headpole and the other at the *** is plasticity in the production of valve morphologies,and a variety of vegetative valve and spore combinations are *** population of *** *** has initial valves of over 90 μm in length,and all of the initial cells encountered are acostate and bear two *** observations suggest that either spores are the product of sexual reproduction,or that initial valves may be produced parthenogenetically in *** as products of the sexual process have not been reported in diatoms previously,and parthenogenesis in Meridion was reported previously but discounted in other published *** plasticity of valve morphologies expressed in *** ***,between vegetative valves and spores(and back) across a short temporal period suggests that diatoms can alter their cell wall structure dramatically and quickly in response to external variables.

关键词： Bacillariophyceae diatom Innenschalen internal valves Meridion systematics.

The role of the Mg_(17)Al_(12)-phase in the high-pressure die-cast magnesium-aluminum alloy system

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journal of Magnesium and Alloys 2023年第11期11卷 4235-4246页

作者： j.p.Weiler Meridian Lightweight Technologies Canada

The Mg_(17)Al_(12)β-phase is highly influential to the performance of magnesium-aluminum high-pressure die-casting alloys. numerous studies have investigated the effect of this phase on the room temperature and elevated-temperature mechanical properties as well as the corrosion,flammability, thermal conductivity and castability performance. This work summarizes the results of these works, as well as the studies that describe control of the Mg_(17)Al_(12)-phase through alloying additions that modify the microstructure and resulting alloy performance. The results of this work can be used as a basis for the development of alloying additions that enable modifications to the performance of high-pressure die-cast magnesium-aluminum-based alloys.

关键词： Magnesium alloys HpDC Alloy development properties

Analysing changes in spatial point patterns:A proposal using data from a forest thinning experiment

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Forest Ecosystems 2022年第6期9卷 878-887页

作者： Christian Salas-Eljatib joaquín Riquelme-Alarcon pablo j.Donoso Diego ponce Daniel p.Soto Centro de Modelacion y Monitoreo de Ecosistemas Escuela de Ingeniería ForestalUniversidad MayorSantiagoChile Vicerrectoría de Investigacion y postgrado Universidad de La FronteraTemucoChile Departamento de Silvicultura y Conservacion de la naturaleza Universidad de ChileSantiagoChile Instituto de Bosques y Sociedad Universidad Austral de ChileValdiviaChile Corporacion nacional Forestal ValdiviaChile Departamento de Ciencias naturales y Tecnología Universidad de AysenCoyhaiqueChile

Spatial patterns reveal critical features at the individual and community ***,how to evaluate changes in spatial characteristics remains largely *** assess spatial changes in spatial point patterns by augmenting current statistical functions and *** fitted functions to describe unmarked and marked(tree size)spatial patterns using data from a large-scale silvicultural experiment in southern ***,we compute the mingling index to represent spatial tree *** proffer the pair correlation function difference before and after treatment to detect changes in the unmarked-point pattern of trees and the semivariogram-ratio to evaluate changes in the marked-point *** research provides a quantitative assessment of a critical aspect of forest heterogeneity:changes in spatial unmarked and marked-point *** proposed approach can be a powerful tool for quantifying the impacts of disturbances and silvicultural treatments on spatial patterns in forest ecosystems.

关键词： Spatial diversity Marked-point process Spatial heterogeneity Conspecific Variable-density thinning nothofagus

Food poisoning associated methemoglobinemia: Time to wake up

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World journal of Emergency Medicine 2020年第2期11卷 127-128页

作者： Kamal Kant Sahu Amos lal Ajay Mishra Susan George Department of Internal Medicine Saint Vincent HospitalWorcesterMassachusetts 01608USA

Dear editor,With interest we read the recent article on methemoglobinemia by Chan et al.[1]Through this letter,we would like to add few additional comments regarding methemoglobinemia and its relevance in medicine practice with regards to food *** Chan et al[1]successfully managed their patient of methemoglobinemia and could pinpoint choy sum as the responsible agent,we wonder if there were any more cases of choy sum related to methemoglobinemia detected at the same time in the community?

关键词： letter 1] editor

Microstructural Evolution of Solid-solution-treated Zn-22Al in the Semisolid State

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journal of Materials Science & Technology 2013年第8期29卷 765-774页

作者： M.A.M.Arif M.Z.Omar n.Muhamad j.Syarif p.Kapranos Department of Mechanical and Materials Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600 BangiSelangorMalaysia Department of Materials Science and Engineering The University of SheffieldSir Robert Hadfield BuildingMappin St.Sheffield S1 3JDUK

The effect of solid-solution-treatment on the semisolid microstructure of Zn-22Al with developed dendrites was investigated. Forming Zn-22Al products by semisolid metal processing offers significant advantages, such as reductions in macro-segregation, porosity and forming costs. Thermal and rnicrostructural analyses of the formed Zn-22Al alloy were performed by differential scanning calorimetry, scanning electron microscopy and optical microscopy. The changes in the microstructures and phase transformation in response to various solid- solution-treatments were analysed. In this study, as-cast samples were held isothermally at 330 ℃ for 0.5- 5 h and then partially remelted at a semisolid temperature of 438 ℃ for 1 h to produce a solid-globular grain structure in a liquid matrix. A non-dendritic semisolid microstructure could not be obtained when the traditionally cast Zn 22Al alloy with developed dendrites was subjected directly to partial remelting. After solid-solution-treatment at 330 ℃, the black interdendritic eutectics were dissolved, and the dendritic structures gradually transformed into uniform β structures when the treatment time was increased. The coarsened and merged dendrites were separated as a result of penetration by the liquid phase and melting of the residual eutectic at sites along the former grain boundaries. The microstructure of the solid-solution- treated sample transformed into a small globular structure; the best shape factor of 0.9, corresponding to a particle size of 40 ± 16 μm, is achieved when the sample was treated for 3 h followed by direct partial remelting into its semisolid zone.

关键词： SemisoLid metal processing Solidus Liquidus Dendritic Spherical morphologies

Magnetic Flux Alignment Studies on Entrapped Ferrofuid nanoparticles in poly Vinyl Alcohol Matrix

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journal of Materials Science & Technology 2013年第10期29卷 903-908页

作者： K.jeyasubramanian n.Selvakumar j.Ilakkiya p.Santhoshkumar nikil Satish Sumanta Kumar Sahoo nano Science and Technology Lab Department of Mechanical EngineeringMepco Schlenk Engineering College Department of ECE Jay Shriram Group of Institutions Department of ECE Adhiyamaan College of Engineering Department of Metallurgical and Materials Engineering National Institute of Technology

Highly surface active super paramagnetic colloidal suspensions of nano crystalline ferrofluid have been synthesized through wet-chemical route. Entrapment of magnetic domains presented in the nano ferrofluid in a polymer matrix like poly vinyl alcohol film was accomplished by developing polymer composite film in between two magnetic poles by solvent casting method. Similarly poly vinyl alcohol-ferrofluid composite films were also developed in the absence of magnetic field. Atomic force microscopy image of nano-composite film makes it clear that the film developed in the absence of magnetic field possesses randomly oriented domains, whereas film developed with magnetic field shows well aligned flux lines. The characteristics and nature of forces acting between magnetic domains along the magnetic flux lines were explored from magnetic force microscopy imaging. The number of flux lines developed in the polymer matrix was observed to be directly proportional to applied external magnetic field. Approximate number of magnetic lines passing through unit area of composite film was evaluated from line profile data analysis of atomic force microscopy image. The particle sizes of the nanoparticles encapsulated in the polymer matrix were found to be in the range of 10- 20 nm. Scanning electron microscopy micrographs confirm aggregation of ferrofluid particles of ribbon like morphology along the magnetic flux lines. Magnetic properties of the entrapped nanoparticles in polymer matrix film were analyzed using vibrating sample magnetometer at room temperature. The super paramagnetic nature and other magnetic properties were evaluated from the hysteresis loop.

关键词： Ferrofiuid Magnetic field fines Alignment Super paramagnetic

Computer Simulation Study of Thermal Conduction in 1D Chains of Anharmonic Oscillators

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Communications in Theoretical physics 2013年第3期59卷 361-364页

作者： Tejal n.Shah p.n.Gajjar Bhavan's Sheth R.A.College of Science KhanpurAhmedabad 380 001GujaratIndia Department of physics University School of SciencesGujarat UniversityAhmedabad 380 009GujaratIndia

In this work thermal conduction in one-dimensional （1D） chains of anharmonic oscillators are studied using computer simulation. The temperature profile, heat flux and thermal conductivity are investigated for chain length n = 100, 200, 400, 800 and 1600. In the computer simulation anharmonicity is introduced due to Fermi-pasta- U1am-β （FpU-β） model For substrate interaction, an onsite potential due to Frenkel-Kontorova （FK） model has been used. numerical simulations demonstrate that temperature gradient scales behave as n-1 linearly with the relation j = 0.1765/n. For the thermal conductivity K, Kn to n obey the linear relation of the type Kn = 0.8805n. It is shown that thermal transport is dependent on phonon-phonon interaction as web as phonon-lattice interaction. The thermal conductivity increases linearly with increase inanharmonicity and predicts relation κ =0.133 ＋ 0.804β. It is also concluded that for higher value of the strength of the onsite potential system tends to a thermal insulator.

关键词： heat conduction thermal conductivity Anharmonic oscillator Fermi-pasta-Ulam model Frenkel-Kontorova model

ERROR ESTIMATES FOR THE TIME DISCRETIZATIOn FOR nOnLInEAR MAXWELL'S EQUATIOnS

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journal of Computational Mathematics 2008年第5期26卷 677-688页

作者： Mavián Slodika ján Bua jr. Department of Mathematical Analysis Ghent University

This paper is devoted to the study of a nonlinear evolution eddy current model of the type δtB（H）＋ △↓× （ △↓ × H） =0 subject to homogeneous Dirichlet boundary conditions H × v = 0 and a given initial datum. Here, the magnetic properties of a soft ferromagnet are linked by a nonlinear material law described by B（H）. We apply the backward Euler method for the time discretization and we derive the error estimates in suitable function spaces. The results depend on the nonlinearity of B（H）.

关键词： Electromagnetic field nonlinear eddy current problem Time discretization,Error estimate.