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8篇 您的检索式:作者名="Christopher Baird"
    题名 作者 年代 出处 被引量
1Tricuspid regurgitation or Ebsteinoid dysplasia of the tricuspid valve in congenitally corrected transposition: Is valvuloplasty necessary at anatomic repair?显示文摘Patrick O. Myers Victor Bautista-Hernandez Christopher W. Baird Sitaram M. Emani Gerald R. Marx Pedro J. del Nido 2013The Journal of Thoracic and Cardiovascular Surgery2013,,:1
2Anticoagulation and pediatric extracorporeal membrane oxygenation:Impact of activated clotting time and heparin dose on surviva1显示文摘Christopher W Baird David Zurakowski 2007Ann Thorac Surg2007,83,:1
3A question of evidence : A critique of risk assessment models used in the justice system 显示文摘Christopher Baird 2009National Council on Crime and Delinquency2009,,:1
4Bioprosthetic Valve Size Selection to Optimize Aortic Valve ReplacementSurgical Outcome: A Fluid-Structure Interaction Modeling Study显示文摘Aortic valve replacement(AVR)remains a major treatment option for patients with severe aortic valve disease.Clinical outcome of AVR is strongly dependent on implanted prosthetic valve size.Fluid-structure interaction(FSI)aortic root models were constructed to investigate the effect of valve size on hemodynamics of the implanted bioprosthetic valve and optimize the outcome of AVR surgery.FSI models with 4 sizes of bioprosthetic valves(19(No.19),21(No.21),23(No.23)and 25 mm(No.25))were constructed.Left ventricle outflow track flow data from one patient was collected and used as model flow conditions.Anisotropic Mooney–Rivlin models were used to describe mechanical properties of aortic valve leaflets.Blood flow pressure,velocity,systolic valve orifice pressure gradient(SVOPG),systolic cross-valve pressure difference(SCVPD),geometric orifice area,and flow shear stresses from the four valve models were compared.Our results indicated that larger valves led to lower transvalvular pressure gradient,which is linked to better post AVR outcome.Peak SVOPG,mean SCVPD and maximum velocity for Valve No.25 were 48.17%,49.3%,and 44.60%lower than that from Valve No.19,respectively.Geometric orifice area from Valve No.25 was 52.03%higher than that from Valve No.19(1.87 cm2 vs.1.23 cm2).Implantation of larger valves can significantly reduce mean flow shear stress on valve leaflets.Our initial results suggested that larger valve size may lead to improved hemodynamic performance and valve cardiac function post AVR.More patient studies are needed to validate our findings.Caili Li Dalin Tang Jing Yao Christopher Baird Haoliang Sun Chanjuan Gong Luyao Ma Yanjuan Zhang Liang Wang Han Yu Chun Yang Yongfeng Shao 2021Computer Modeling in Engineering & Sciences2021,,4:1
5Hypothermia postpones DNA damage repair in irradiated cells and protects against cell killing显示文摘Brandon J. Baird Jennifer S. Dickey Asako J. Nakamura Christophe E. Redon Palak Parekh Yuri V. Griko Khaled Aziz Alexandros G. Georgakilas William M. Bonner Olga A. Martin 2011Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis2011,,1:1
6Computational Modeling of Human Bicuspid Pulmonary Valve Dynamic Deformation in Patients with Tetralogy of Fallot显示文摘Pulmonary valve stenosis(PVS)is one common right ventricular outflow tract obstruction problem in patients with tetralogy of Fallot(TOF).Congenital bicuspid pulmonary valve(BPV)is a condition of valvular stenosis,and the occurrence of congenital BPV is often associated with TOF.Dynamic computational models of normal pulmonary root(PR)with tri-leaflet and PR with BPV in patients with TOF were developed to investigate the effect of geometric structure of BPV on valve stress and strain distributions.The pulmonary root geometry included valvular leaflets,sinuses,interleaflet triangles and annulus.Mechanical properties of pulmonary valve leaflet were obtained from biaxial testing of human PV leaflet,and characterized by an anisotropic Mooney-Rivlin model.The complete cardiac cycle was simulated to observe valve leaflet dynamic stress/strain behaviors.Our results indicated that stress/strain distribution patterns of normal tri-leaflet pulmonary valve(TPV)and the BPV were different on valve leaflets when the valve was fully open,but they were similar when valves were completely closed.When the valve was fully open,the BPV maximum stress value on the leaflets was 197.2 kPa,which was 94.3%higher than of the normal TPV value(101.5 kPa).During the valve was fully open,the stress distribution in the interleaflet triangles region of the PR was asymmetric in the BPV model compared with that in the TPV model.The geometric orifice area value in the completely opened position of BPV model was reduced 55.6%from that of the normal PV.Our initial results demonstrated that valve geometrical variations with BPV may be a potential risk factor linked to occurrence of PVS in patients with TOF.Computational models could be a useful tool in identifying possible linkage between valve disease development and biomechanical factors.Large-scale clinical studies are needed to validate these preliminary findings.Caili Li Christopher Baird Jing Yao Chun Yang Liang Wang Han Yu Tal Geva Dalin Tang 2019Computer Modeling in Engineering & Sciences2019,,4:0
7Leakage pressures for gasketless superhydrophobic fluid interconnects for modular lab-on-a-chip systems显示文摘Chip-to-chip and world-to-chip fluidic interconnections are paramount to enable the passage of liquids between component chips and to/from microfluidic systems.Unfortunately,most interconnect designs add additional physical constraints to chips with each additional interconnect leading to over-constrained microfluidic systems.The competing constraints provided by multiple interconnects induce strain in the chips,creating indeterminate dead volumes and misalignment between chips that comprise the microfluidic system.A novel,gasketless superhydrophobic fluidic interconnect(GSFI)that uses capillary forces to form a liquid bridge suspended between concentric through-holes and acting as a fluid passage was investigated.The GSFI decouples the alignment between component chips from the interconnect function and the attachment of the meniscus of the liquid bridge to the edges of the holes produces negligible dead volume.This passive seal was created by patterning parallel superhydrophobic surfaces(water contact angle>150°)around concentric microfluidic ports separated by a gap.The relative position of the two polymer chips was determined by passive kinematic constraints,three spherical ball bearings seated in v-grooves.A leakage pressure model derived from the Young-Laplace equation was used to estimate the leakage pressure at failure for the liquid bridge.Injection-molded,Cyclic Olefin Copolymer(COC)chip assemblies with assembly gaps from 3 to 240μm were used to experimentally validate the model.The maximum leakage pressure measured for the GSFI was 21.4 kPa(3.1 psig),which corresponded to a measured mean assembly gap of 3μm,and decreased to 0.5 kPa(0.073 psig)at a mean assembly gap of 240μm.The effect of radial misalignment on the efficacy of the gasketless seals was tested and no significant effect was observed.This may be a function of how the liquid bridges are formed during the priming of the chip,but additional research is required to test that hypothesis.Christopher R.Brown Xiaoxiao Zhao Taehyun Park Pin-Chuan Chen Byoung Hee You Daniel S.Park Steven A.Soper Alison Baird Michael C.Murphy 2021Microsystems & Nanoengineering2021,7,5:0
8Anisotropic Models of Human Pulmonary Root with Bicuspid Pulmonary Valve in Patients with Tetralogy of Fallot: Pulmonary Root Function Assessment and Mechanical Stress Analysis显示文摘Background Tetralogy of Fallot(TOF)is the most common cyanotic heart defect,accounting for 10%of all congenital defects.Pulmonary valve stenosis(PVS)is one common right ventricular outflow tract obstruction problem in patients with TOF.Congenital bicuspid pulmonary valve(BPV)is a condition of valvular stenosis,which morphologic feature is the presence of only two pulmonary leaflets instead of the normal tri-leaflet.Congenitally BPV are uncommon and the occurrence is often associated with TOF.Methods The three-dimensional geometric reconstruction of pulmonary root(PR)were based on well-accepted mathematical analytic models with physiological parameters obtained from a typical sample of the pulmonary root used in clinical surgery.The PR geometry included valvular leaflets,sinuses,interleaflet triangles and annulus.The dynamic computational models of normal PR with tri-leaflet and PR with BPV in patients with TOF were developed to investigate the effect of geometric structure of BPV on valve stress and strain distributions and the geometric orifice area.Mechanical properties of pulmonary valve leaflet were obtained from biaxial testing of human pulmonary valve left leaflet,and characterized by an anisotropic Mooney-Rivlin model.The complete cardiac cycle was simulated to observe valve leaflet dynamic stress and strain behaviors.Results Our results indicated that stress/strain distribution patterns of normal tri-leaflet pulmonary valve(TPV)and the BPV were different on valve leaflets when the valve was fully open,but they were similar when valves were completely closed.When the valve was fully open,the BPV maximum stress value on the leaflets was 218.1 kPa,which was 128.0%higher than of the normal TPV value(95.6 kPa),and BPV maximum strain value on the leaflets was 70.7%higher than of the normal TPV.The location of the maximum stress from TPV and BPV were also different,which were found at the bottom of the valve near the leaflet attachment for TPV and the vicinity of cusp of the fusion of two leaflets for BPV,respectively.During the valve was fully open,the stress distribution in the interleaflet triangles region of the PR was more asymmetric in the BPV model compared with that in the normal TPV model,and the largest change on the PR with the geometrical variations in the two models was 39.6%in maximum stress.This stress asymmetry indicates that BPV may be one of the causes of post-stenotic pulmonary artery dilatation and aneurysm in patients with TOF.The cusp of the BPV model showed significant eccentricity during peak systolic period,and its geometric orifice area value in the completely opened position of valve was reduced 57.5%from that of the normal TPV model.Conclusions Our initial results demonstrated that valve geometrical variations with BPV may be a potential risk factor linked to occurrence of PVS in patients with TOF.Computational models could be used as an effective tool to identifying possible linkage between pulmonary valve malformation disease development and biomechanical factors,better design of artificial valves and new surgical procedures without testing those on patients.Large-scale clinical studies are needed to validate these preliminary findings.Caili Li Christopher Baird Jing Yao Chun Yang Liang Wang Han Yu Tal Geva Dalin Tang 2019医用生物力学2019,34,A01:0
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