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Challenges and opportunities in improving left ventricular remodelling and clinical outcome following surgical and trans-catheter aortic valve replacement

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Frontiers of Medicine 2021年第3期15卷 416-437页

作者： Xu Yu Jin Mario Petrou Jiang ting hu Ed d Nicol John R Pepper Surgical Echo-Cardiology Services Oxford Heart CentreJohn Radcliffe HospitalOxford University Hospitals NHS Foundation TrustOxford OX39DUUK Cardiac Surgical Physiology and Genomics Group Nuffield Division of Clinical Laboratory SciencesRadcliffe Department of MedicineUniversity of OxfordOxford OX39DUUK department of Cardiac Surgery Royal Brompton HospitalLondon SW36NPUK National Heart and Lung Institute Imperial College LondonLondon SW36LYUK NIHR Imperial Biomedical Research Centre London W21NYUK department of Cardiology Royal Brompton HospitalLondon SW36NPUK

Over the last half century,surgical aortic valve replacement(SAVR)has evolved to offer a durable and efficient valve haemodynamically,with low procedural complications that allows favourable remodelling of left ventricular(LV)structure and *** latter has become more challenging among elderly patients,particularly following trans-catheter aortic valve implantation(tAVI).Precise understanding of myocardial adaptation to pressure and volume overloading and its responses to valve surgery requires comprehensive assessments from aortic valve energy loss,valvular-vascular impedance to myocardial activation,force-velocity relationship,and myocardial *** hypertrophy and myocardial fibrosis remains as the structural and morphological focus in this *** intervention in asymptomatic aortic stenosis or regurgitation along with individualised management of hypertension and atrial fibrillation is likely to improve patient *** pacing via the His-Purkinje system for conduction abnormalities,further reduction in para-valvular aortic regurgitation along with therapy of angiotensin receptor blockade will improve patient outcome by facilitating hypertrophy regression,LV coordinate contraction,and global vascular *** leaflet thromboses require anticoagulation while impaired access to coronary ostia risks future tAVI-in-tAVI or coronary *** comparable long-term durability and the resolution of tAVI relat.d.complications become available,SAVR remains the first choice for lower risk younger patients.

关键词： surgical aortic valve replacement trans-catheter aortic valve implantation left ventricular hypertrophy and fibrosis myocardial force-velocity relationship His-Purkinje pacing renin-angiotensin system inhibitors coronary access impairment

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Influence of cement-fly ash-gravel pile-support.d.approach embankment on abutment piles in soft ground

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第5期10卷 977-985页

作者： d.Xiao G.L.Jiang d.Liao Y.F.hu X.F.Liu School of Civil Engineering Southwest Jiaotong University Highway Planning Survey Design and Research Institute Sichuan Provincial Transport Department

Abutment piles in soft ground may be subject.d.to both vertical and horizontal soil movements resulting from approach embankment loads. to constrain the soil movements, the soft soil ground beneath the approach embankment is often improved using composite pile foundations, which aim at mitigating the bump induced by high-speed trains passing through the bridge. So far, there is limit.d.literature on exploring the influence of the degree of ground improvement on abutment piles installed in soft soil grounds. In this paper, a series of three-dimensional （3d） centrifuge model tests was performed on an approach embankment over a silty clay deposit improved by cement-fly ash-gravel （CFG） piles combined with geogrid. Emphasis is placed on the effects of ground replacement ratio （m） on the responses of the abutment piles induced by embankment loads. Meanwhile, a numerical st.d. was conduct.d.with varying ground replacement ratio of the pile-reinforced grounds. Results show that the performance of the abutment piles is significantly improved when reinforcing the ground with CFG piles beneath the approach embankment. Interestingly, there is a threshold value of the replacement ratio of around 4.9% above which the effect of CFG pile foundations is limit.d. this implies that it is essential to optimize the ground improvement for having a cost-effective design while minimizing the risk of the bump at the end of bridge.

关键词： Abutment pile Soft soilSoil movement Ground improvement Load transfer

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Soil particle size distribution and its relationship with soil water and salt under mulched drip irrigation in Xinjiang of China

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Science China(technological Sciences) 2011年第6期54卷 1568-1574页

作者： hu HongChang tIAN FuQiang hu HePing department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

Soil particle size distribution(PSd),one of the most important soil physical attributes,is of great importance to soil water movement,soil erosion and soil solute *** this st.d.,the soil PSd of 563 soil samples from the mulched drip irrigat.d.cotton fields in Xinjiang of China were measured by laser diffraction particle size *** soil PSd characteristics and its relations with soil water and salt were st.d.ed by using the combined methods of textural triangle,fractal and multifractal *** results showed very low clay content(about 1.52%) while really high sand content of the st.d.ed soil,and a complex shape of bimodal or unimodal of soil *** results also showed that the two indices,i.e.,standard deviation and the peak value of soil particle relative volumes,were good indicators of soil PSd and thus had good relations with fractal and multifractal *** correlative analysis further indicat.d.that the mulched drip irrigation had a significant impact on the distribution of the soil salt,while this impact withered for the deeper soil *** soil texture feature was found to dominate soil water and salt.d.stribution,especially the surface soil salt content and the deep soil water content.

关键词： soil particle size distribution soil water and salt mulched drip irrigation fractal analysis multifractal analysis textural triangle

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COUPLEd ANALYSIS FOR tHE HARVEStING StRUCtURE ANd tHE MOdULAtING CIRCUIt IN A PIEZOELECtRIC BIMORPH ENERGY HARVEStER

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Acta Mechanica Solida Sinica 2007年第4期20卷 296-308页

作者： Yuantai hu ting hu Qing Jiang department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China department of Mechanical Engineering University of California Riverside CA 92521 USA

the authors analyze a piezoelectric energy harvester as an electro-mechanically coupled system. the energy harvester consists of a piezoelectric bimorph with a concentrat.d.mass attached at one end, called the harvesting structure, an electric circuit for energy storage, and a rectifier that converts the AC output of the harvesting structure into a dC input for the storage circuit. the piezoelectric bimorph is assumed to be driven into flexural vibration by an ambient acoustic source to convert the mechanical energies into electric energies. the analysis indicates that the performance of this harvester, measured by the power density, is characterized by three important non-dimensional parameters, i.e., the non-dimensional inductance of the storage circuit, the non-dimensional aspect ratio （length/thickness） and the non-dimensional end mass of the harvesting structure. the numerical results show that：（1） the power density can be optimized by varying the non-dimensional inductance for each fixed non-dimensional aspect ratio with a fixed non-dimensional end mass; and （2） for a fixed non-dimensional inductance, the power density is maximized if the non-dimensional aspect ratio and the non-dimensional end mass are so chosen that the harvesting structure, consisting of both the piezoelectric bimorph and the end mass attached, resonates at the frequency of the ambient acoustic source.

关键词： energy harvester piezoelectric bimorph harvesting structure RLC modulatingcircuit coupled interaction power density

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deviations of the lepton mapping matrix from the Harrison-Perkins-Scott form

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Chinese Physics C 2010年第10期34卷 1547-1555页

作者： R.Friedberg t.d.Lee Physics department Columbia UniversityNew York China Center of Advanced Science and technology(CCASt/World Lab.)

We propose a simple set of hypotheses governing the deviations of the leptonic mapping matrix from the Harrison-Perkins-Scott （HPS） form. these deviations are supposed to arise entirely from a perturbation of the mass matrix in the charged lepton sector. the perturbing matrix is assumed to be purely imaginary （thus maximally t-violating） and to have a strength in energy scale no greater （but perhaps smaller） than the muon mass. As we shall show, it then follows that the absolute value of the mapping matrix elements pertaining to the tau lepton deviate by no more than O（（mμ/mτ）^2） ≈ 3.5 ×10^-3 from their HPS values. Assuming that （mμ/mτ）^2 can be neglect.d. we derive two simple constraints on the four parameters θ12,θ23, θ31, and δ of the mapping matrix. these constraints are independent of the details of the imaginary t-violating perturbation of the charged lepton mass matrix. We also show that the e and μ parts of the mapping matrix have a definite form governed by two parameters α and β; any deviation of order mμ/mτ can be accommodat.d.by adjusting these two parameters.

关键词： lepton mapping matrix CP and t violation Jarlskog invariant timeon

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Numerical modeling of thermally-induced fractures in a large rock salt mass

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第5期10卷 844-855页

作者： d.t. Ngo FL. Pellet MINES Paristech PSL Research University Fontainebleau France

Numerical modeling of thermally-induced fractures is a concern for many geo-structures including deep underground energy storage caverns. In this paper, we present the numerical simulation of a large-scale cooling experiment performed in an underground rock salt mine. the theory of fracture mechanics was embedded in the extended finite element code used. the results provide reliable information on fracture location and fracture geometry. Moreover, the timing of the fracture onset, as well as the stress redis- tribution due to fracture propagation, is highlight.d. the conclusions of this numerical approach can be used to improve the design of rock salt caverns in order to guarantee their integrity in terms of both their tightness and stability.

关键词： Fracture mechanics thermal loading Extended finite element method (XFEM)simulation Rock salt

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Cognitive frailty in the elderly:a concept analysis

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Frontiers of Nursing 2023年第4期10卷 393-398页

作者： Yi-Yin hu Ronnell d.dela Rosa department of Nursing The Affiliated Hospital of Guizhou Medical UniversityGuiyangGuizhou 550000China School of Nursing Philippine Women’s UniversityMalateManila 1004Philippines

Frailty is a recession of age-relat.d.reserves caused by a variety of causes and is becoming the most important clinical syndrome that affects the health of the *** the elderly,frailty and cognitive dysfunction often exist,and some people have proposed cognitive *** frailty is an elderly syndrome that increases the risk of dementia,in the same time,and can independently predict the adverse health outcomes of the patient and affect the quality of the patient's *** paper,under the guidance of Walker and Avant method,provides theoretical basis for early recognition and intervention of cognitive weakness in the elderly.

关键词： antecedents cognition concept analysis consequences defining attributes empirical referents frailty

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Strategies for h-Adaptive Refinement for a Finite Element treatment of Harmonic Oscillator Schrodinger Eigenproblem

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Communications in theoretical Physics 2010年第6期53卷 1017-1023页

作者： t.d.Young R.Armiento Instytut Podstawowych Prolemow techniki Polskiej Academia Nauk ul. Pawinskiego 5b theoretische Physik Universitat Bayreuth

A Schrodinger eigenvalue problem is solved for the 219 quantum simple harmonic oscillator using a finite element.d.scretization of real space within which elements are adaptively spatially refined. We compare two competing methods of adaptively discretizing the real-space grid on which computations are performed without modifying the standard polynomial basis-set traditionally used in finite element interpolations; namely, （i） an application of the Kelly error estimator, and （ii） a refinement based on the local potential level. When the performance of these methods are compared to standard uniform global refinement, we find that they significantly improve the total time spent in the eigensolver.

关键词： adaptive finite element analysis Harmonic oscillator problems Schrodinger equation

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Multi-Axis Attention With Convolution Parallel Block for Organoid Segmentation

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1295-1297页

作者： Pengwei hu Xun deng Feng tan Lun hu Xinjiang technical Institute of Physics and Chemistry Chinese Academy of SciencesUrumqi 830011 University of Chinese Academy of Sciences Beijing 100049 Xinjiang Laboratory of Minority Speech and Language Information Processing Urumqi 830011China Merck KGaA Darmstadt 64293Germany

dear Editor,this letter presents an organoid segmentation model based on multi-axis attention with convolution parallel *** adeptly captures dynamic dependencies within bright-field microscopy images,improving global ... 详细信息

关键词： letter convolution organo

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Facile synthesis of large-area ultrathin two-dimensional supramolecular nanosheets in water

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Nano Research 2020年第3期13卷 868-874页

作者： Bojian hu Peiyi Wu State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceLaboratory far Advanced MaterialsFudan UniversityShanghai 200433China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of ChemistryChemical Engineering and BiotechnologyCenter for Advanced Low-Dimension MaterialsDonghua UniversityShanghai 201620China

Synthesizing large-area ultrathin two-dimensional(2d)nanostructures in aqueous media has received considerable increasing attention but remains a big ***,we report a facile method for the synthesis of two unprecedent.d.large-area ultrathin 2d supramolecular nanosheets via ionic self-assembly in *** consideration of electrostatic interaction and repulsive effect.d.protonat.d.tetrakis(4-carboxyphenyl)porphyrin(tCPP)or Fe(III)tetra(4-carboxyphenyl)porphine chloride(tCPP(Fe))as connection vertex and protonat.d.bis(2-dimethylaminoethyl)ether(BdMAEE)unit as bridging edge connect with each other to form few-layer 2d nanosheet with a thickness of^1.8–1.9 nm,while the lateral size can close to one hundred ***,the well-dispersed 2d tCPP(Fe)-BdMAEE with heme-like active center displays intrinsic peroxidase-like catalytic activity,which can be used to detect hydrogen *** present facile strategy highlights new opportunities in constructing large-area ultrathin 2d supramolecular nanomaterials and paves the avenue to expand their potential applications.

关键词： large-area ultrathin two-dimensional supramolecular nanosheets peroxidase-like catalytic activity

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