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World Journal of Emergency Medicine 2020年第1期11卷 54-59页

作者： Harith Fernando Nicholas adams Biswadev Mitra Emergency and Trauma Centre The Alfred HospitalMelbourneVictoriaAustralia National Trauma Research Institute The Alfred HospitalMelbourneVictoriaAustralia Department of Epidemiology and Preventive Medicine Monash UniversityMelbourneVictoriaAustralia

Dear editor,Patients with supraventricular tachycardia(SVT)commonly present to the emergency department(ED).Current guidelines[1,2]do not recommend routine pathology testing and a report on the topic has questioned their role.A systematic review concluded that troponin testing is commonly performed with a high proportion of positive fi ndings,but these results were not associated with major adverse cardiac events.[3]The conclusions of this review were limited by paucity of data and heterogeneity among studies.

关键词： tachycardia routine pathology

Bioactivity of quaternary glass prepared from bentonite clay

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Journal of Advanced Ceramics 2016年第1期5卷 47-53页

作者： Luqman A.adams Enobong R.ESSIEN Department of Chemistry University of Lagos Nigeria Department of Chemical Sciences Bells University of Technology P.M.B 1015 Ota Ogun Nigeria

Alkoxysilane precursors are the most widely used silica source for sol-gel preparation of silicate-based bioactive glass. However, due to their high cost, alternative sources such as bentonite clay are desirable. In the present work, bentonite clay was reacted with sodium hydroxide (NaOH) to extract sodium metasilicate (Na2SiO3). The obtained Na2SiO3 was converted to gel which was then sintered at 950 ℃ for 3 h to give the bioactive glass in the quaternary composition SiO2-NaO-CaO-P2O5. The resulting glass was incubated in simulated body fluid (SBF) for 0-7 days to evaluate the bioactivity. Furthermore, glass samples were characterized before and after SBF study by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Results obtained showed the presence of Na2Ca2Si3O9 (combeite) crystal as the major crystalline phase and the formation of hydroxyapatite (HA) and hydroxycarbonated apatite (HCA) on the surface of the glass after immersion in SBF. The material showed potentials for application as scaffold in bone tissue repair.

关键词： bentonite clay bioactivity alkoxysilane hydroxyapatite (HA) bone repair

A note on hydrodynamics from dissipative particle dynamics

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Applied Mathematics and Mechanics(English Edition) 2018年第1期39卷 63-82页

作者： X. BIAN Z. LI N.A. adams Department of Mechanical Engineering Technical University of Munich Munchen 85748 Germany Division of Applied Mathematics Brown University Rhode Island 02912 U. S. A.

We calculate current correlation functions （CCFs） of dissipative particle dy- namics （DPD） and compare them with results of molecular dynamics （MD） and solutions of linearized hydrodynamic equations. In particular, we consider three versions of DPD, the empirical/classical DPD, coarse-grained （CG） DPD with radial-direction interactions only and full （radial, transversal, and rotational） interactions between particles. To fa- cilitate quantitative discussions, we consider specifically a star-polymer melt system at a moderate density. For bonded molecules, it is straightforward to define the CG variables and to further derive CG force fields for DPD within the framework of the Mori-Zwanzig formalism. For both transversal and longitudinal current correlation functions （TCCFs and LCCFs）, we observe that results of MD, DPD, and hydrodynamic solutions agree with each other at the continuum limit. Below the continuum limit to certain length scales, results of MD deviate significantly from hydrodynamic solutions, whereas results of both empirical and CG DPD resemble those of MD. This indicates that the DPD method with Markovian force laws possibly has a larger applicability than the continuum description of a Newtonian fluid. This is worth being explored further to represent gen- eralized hydrodynamics.

关键词： dissipative particle dynamics (DPD) fluctuating hydrodynamics molec-ular dynamics (MD) coarse-graining Mori-Zwanzig projection

Re-mention of an old neurodegenerative disease:Alzheimer's disease

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Chinese Science Bulletin 2013年第15期58卷 1731-1736页

作者： ZHANG Peng adams Ursula YUAN ZengQiang State Key Laboratory of Brain and Cognitive Sciences Institute of BiophysicsChinese Academy of Sciences Biological Sciences The University of Chicago

Alzheimer's disease(AD),the most common form of neuropsychiatric disorder,is characterized by neuronal degeneration and inexorably progressing dementia,especially in the elderly *** a rapidly aging population in both developed and developing countries,AD has emerged as one of the largest growing problems *** drugs improve the symptoms of AD,but do not have any profound intervention to delay its ***,understanding the molecular mechanisms underlying the genes tied to AD will be crucial to the development of therapeutic *** review will summarize the aetiology,pathology,and the evidence for the genetic components in AD,discuss the proposed amyloid cascade and the following tau hyperphosphorylation hypothesises,oxidative stress mediated neuronal cell death,as well as the function of Retromer complex during the developing of *** laboratory's current research progress and the challenges that still remained will be also highlighted.

关键词：神经退行性疾病阿尔茨海默氏症阿尔茨海默氏病 Complex 老年痴呆症神经细胞死亡淀粉样蛋白精神障碍

Construction quality acceptance performance-related specifications for chip seals

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第4期6卷 337-348页

作者： Javon adams Cassie Castorena Y.Richard Kim Department of Civil Construction and Environmental Engineering North Carolina State University

The research described herein details the establishment of a framework for construction quality acceptance performance-related specifications(PRS) for chip seal surface treatments. This paper establishes acceptance quality characteristics(AQCs) and relationships between the AQCs and related chip seal performance measures. This work is a critical step in developing PRS for constructed chip seal treatments and establishing suitable guidelines for the PRS. The main objective of this paper is to determine appropriate test methods to evaluate each defined AQC. The relationships that are established between the AQCs and chip seal performance are used to define performance ranges and threshold values for a particular performance measure. These performance ranges and threshold values then can be used to define pay factors for the constructed chip seal section. The threshold values and pay factors for each AQC described herein are preliminary recommendations and require further validation prior to implementation. However, this research demonstrates how these PRS would be utilized to ensure acceptable chip seal construction quality in the *** developed construction quality acceptance PRS framework uses the percent within limits(PWL) concept to determine whether a chip seal lot passes the PRS threshold values and whether the contractor receives full pay, is subject to a pay penalty, or fails the construction PRS and must correct the chip seal within the first year in service, which constitutes the typical warranty period for contracted chip seal ***, recommendations are made as to the next steps in the development and validation of these construction quality acceptance PRS that are needed for implementation by contractors and state roadway maintenance agencies.

关键词： Performance-related specifications(PRS) Chip seal Construction Quality assurance Percent within limits

China's “Stop-go Pattern”Economy and its Choice of Macroeconomic Policies——A Simple Macroeconometric Model

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南开经济研究 1994年第S1期 12-20页

作者： F.Gerard adams Director of Economics Research Unit of University of Pennsylvania U. S. A

China has achievedhigh growth rates since1949, when compared witheither advanced economies,developing economies, oreven with the former SovietUnion bloc. Some econo-mists (e. g. F. G. adams

关键词：军令

Parallel Algebraic Multigrid Methods in Gyrokinetic Turbulence Simulations

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Communications in Computational Physics 2007年第5期2卷 881-899页

作者： M.F.adams Y.Nishimura Columbia University APAM500 W.120th St.Rm 200MC 4701New YorkNY 10027USA Department of Physics and Astronomy University of CaliforniaIrvineCA 92697-4575USA.

Parallel algebraic multigrid methods in gyrokinetic turbulence simulations are *** equations of the elliptic operator−■^(2)u+αu=f(with bothα=0 and α≠0)are ubiquitous in magnetically confined fusion plasma ***αis equal to zero a“pure”Laplacian or Poisson equation results and whenαis greater than zero a so called Helmholtz equation is *** a gyrokinetic turbulence simulation model as a testbed,we investigate the performance characteristics of basic classes of linear solvers(direct,one-level iterative,and multilevel iterative methods)on 2D unstructured finite element method(FEM)problems for both the Poisson and the Helmholtz equations.

关键词： Algebraic multigrid gyrokinetic Poisson equation particle in cell simulation.

Smoothed particle hydrodynamics:Methodology development and recent achievement

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Journal of Hydrodynamics 2022年第5期34卷 767-805页

作者： Chi Zhang Yu-jie Zhu Dong Wu Nikolaus A.adams Xiangyu Hu TUM School of Engineering and Design Technical University of MunichMunichGermany Xi’an Research Institute of High Technology Xi’an 710025China

Since its inception,the full Lagrangian meshless smoothed particle hydrodynamics(SPH)has experienced a tremendous enhancement in methodology and impacted a range of multi-physics applications in science and *** review presents a concise survey on latest developments and achievements of the SPH method,including:(1)Brief review of theory and fundamental with kernel corrections,(2)The Riemann-based SPH method with dissipation limiting and high-order data reconstruction by using MUSCL,WENO and MOOD schemes,(3)Particle neighbor searching with particle sorting and efficient dual-criteria time stepping schemes,(4)Total Lagrangian formulation with stablized,dynamics relaxation and hourglass control schemes,(5)Fluid-structure interaction scheme with interface treatments and multi-resolution discretizations,(6)Novel applications of particle relaxation in SPH methodology for mesh and particle *** but not least,benchmark tests for validating computational accuracy,convergence,robustness and efficiency are also supplied accordingly.

关键词： Smoothed particle hydrodynamics(SPH) Riemann-based SPH update and total Lagrangian formulations fluid-structure interaction mesh and particle generation

Senescence of human vocal fold fibroblasts in primary culture

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Journal of Biomedical Science and Engineering 2010年第2期3卷 148-159页

作者： George M. adams Chet C. Xu roger W. Chan 不详

This study examined the replicative senescence of primary-culture human vocal fold fibroblasts, in terms of changes in gross chromosomal structure with sub- culturing, and population doubling time (PDT). The mRNA expressions of 14 target genes were also examined. The objectives were to identify the onset of senescence for establishing the acceptable limit of sub-culturing, and to better understand the effect of cellular aging on matrix protein regulation in the vocal fold. Gross chromosomal changes in vocal fold fibroblasts from a 58-year-old woman were karyotyped with Giemsa stain. Proliferation of the fibroblasts was determined with cell recovery and PDT calculation. Transcript levels of the target genes were found by RT-PCR. Onset of significant chromosomal anomalies was seen with passage 5. For mRNA expressions, significant increases with passaging were observed in collagenase, macrophage elastase, lysyl oxidase and fibromodulin, whereas significant downregulation was detected in decorin, procollagen I, hyaluronic acid-synthase 2 and collagen III. This modulation pattern suggested that fibroblasts underwent in vitro aging, consistent with the significant increase in PDT. The inception of senescence did not occur until passage 5. These findings may facilitate the development of representative in vitro models for testing tissue engineering approaches involving primary-culture fibroblasts.

关键词： Larynx Extracellular Matrix Cell Proliferation Replicative Senescence Tissue Engineering

Formation and speciation of disinfection byproducts during chlor(am)ination of aquarium seawater

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Journal of Environmental Sciences 2015年第7期27卷 116-124页

作者： Haiting Zhang Huiyu Dong Craig adams Zhimin Qiang Gang Luan Lei Wang Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Department of Civil and Environmental Engineering Utah State University Water Quality Analysis and Control Center Department of Life Support Equipments for Aquatic AnimalsBeijing Aquarium

The chemistry associated with the disinfection of aquarium seawater is more complicated than that of freshwater, therefore limited information is available on the formation and speciation of disinfection byproducts（DBPs） in marine aquaria. In this study, the effects of organic precursors, bromide（Br-） and pre-ozonation on the formation and speciation of several typical classes of DBPs, including trihalomethanes（THM4）, haloacetic acids（HAAs）,iodinated trihalomethanes（I-THMs）, and haloacetamides（HAc Ams）, were investigated during the chlorination/chloramination of aquarium seawater. Results indicate that with an increase in dissolved organic carbon concentration from 4.5 to 9.4 mg/L, the concentrations of THM4 and HAAs increased by 3.2-7.8 times under chlorination and by 1.1-2.3 times under chloramination. An increase in Br-concentration from 3 to 68 mg/L generally enhanced the formation of THM4, I-THMs and HAc Ams and increased the bromine substitution factors of all studied DBPs as well, whereas it impacted insignificantly on the yield of HAAs. Pre-ozonation with 1 mg/L O3 dose substantially reduced the formation of all studied DBPs in the subsequent chlorination and I-THMs in the subsequent chloramination. Because chloramination produces much lower amounts of DBPs than chlorination, it tends to be more suitable for disinfection of aquarium seawater.

关键词： Disinfection byproducts Chlorination Chloramination Pre-ozonation Bromine substitution factorAquarium seawater