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Yang Ming M INRA, UMR1391 ISPA, F-33140 Villenave d'Ornon, France Bordeaux Sciences Agro, UMR 1391 ISPA, F-33170 Gradignan, - - 2014
Windstorms are the major natural hazard affecting European forests, causing tree damage and timber losses. Modelling tree anchorage mechanisms has progressed with advances in plant architectural modelling, but it is still limited in terms of estimation of anchorage strength. This paper aims to provide a new model for root anchorage, ...
Biglino Giovanni G * These authors contributed equally to this - - 2014
Reliability of computational models for cardiovascular investigations strongly depends on their validation against physical data. This study aims to experimentally validate a computational model of complex congenital heart disease (i.e., surgically palliated hypoplastic left heart syndrome with aortic coarctation) thus demonstrating that hemodynamic information can be reliably extrapolated from the ...
Vismara Riccardo R 3 For Cardio Lab, Università di Milano - Politecnico di Milano, Milan - - - 2014
Cusp extension technique (CET) is a reparative surgical procedure for restoring aortic valve function by suturing patches to the compromised native leaflets. Its outcomes are strongly dependent on the ability of the surgeon. We proposed and tested a novel approach on an in vitro model, aimed at standardizing and simplifying ...
Andrinopoulou Eleni-Rosalina ER Department of Biostatistics, Erasmus MC, Rotterdam, The Netherlands; Department of Cardiothoracic Surgery, Erasmus MC, Rotterdam, The - - 2014
Aortic gradient and aortic regurgitation are echocardiographic markers of aortic valve function. Both are biomarkers repeatedly measured in patients with valve abnormalities, and thus, it is expected that they are biologically interrelated. Loss of follow-up could be caused by multiple reasons, including valve progression related, such as an intervention or ...
Capodanno Davide D Division of Cardiology, Ferrarotto Hospital, University of Catania, Catania, Italy; ETNA Foundation, Catania, Italy. Electronic address: - - 2014
Risk stratification tools used in patients with severe aortic stenosis have been mostly derived from surgical series. Although specific predictors of early mortality with transcatheter aortic valve replacement (TAVR) have been identified, the prognostic impact of their combination is unexplored. We sought to develop a simple score, using preprocedural variables, ...
Jassar Arminder S AS Gorman Cardiovascular Research Group, University of Pennsylvania, Glenolden, Pennsylvania; Department of Surgery, University of Pennsylvania, Philadelphia, - - 2014
Surgical techniques for aortic valve (AV) repair are directed toward restoring normal structural relationships in the aortic root and rely on detailed assessment of root and valve anatomy. Noninvasive three-dimensional (3D) imaging and modeling may assist in patient selection and operative planning. Transesophageal real-time 3D echocardiographic images of 5 patients ...
Rolls A E AE Division of Surgery and Cancer Imperial College London, London, UK - - - 2014
Endovascular intervention has revolutionized the treatment of aortic disease, extending the cohort of patients eligible for repair. Accurate planning for endovascular aortic repair is essential. Recent advances in modern software have demonstrated potential for improving outcomes and enhancing the decision making process beyond 3D measurements and intraoperative navigation techniques. With ...
Pal Siladitya S Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United - - 2014
Aortic dissection (AoD) is a common condition that often leads to life-threatening cardiovascular emergency. From a biomechanics viewpoint, AoD involves failure of load-bearing microstructural components of the aortic wall, mainly elastin and collagen fibers. Delamination strength of the aortic wall depends on the load-bearing capacity and local micro-architecture of these ...
Chen Chia-Yuan - - 2013
The pathology of the human abdominal aortic aneurysm (AAA) and its relationship to the later complication of intraluminal thrombus (ILT) formation remains unclear. The hemodynamics in the diseased abdominal aorta is hypothesized to be a key contributor to the formation and growth of ILT. The objective of this investigation is ...
Casciaro Mariano E - - 2013
Diagnosis and management of thoracic aorta (TA) disease demand the assessment of accurate quantitative information of the aortic anatomy. We investigated the principal modes of variation in aortic 3-dimensional geometry paying particular attention to the curvilinear portion. Images were obtained from extended noncontrast multislice computed tomography scans, originally intended for ...
Alimohammadi Mona - - 2013
Aortic dissection has high morbidity and mortality rates and guidelines regarding surgical intervention are not clearly defined. The treatment of aortic dissection varies with each patient and detailed knowledge of haemodynamic and mechanical forces would be advantageous in the process of choosing a course of treatment. In this study, a ...
Bollache E - - 2013
The aorta plays a major role in the cardiovascular system and its function and structure are primarily affected by aging, eating habits, life style and other cardiovascular risk factors, inducing increased stiffness which is associated with cardiovascular and cerebral morbi-mortality. Our objective was to develop and validate a robust subject-specific ...
Patil Mukesh D - - 2013
Recently fractional-order (FO) differential equations are widely used in the areas of modeling and control. They are multivalued in nature hence their stability is defined using Riemann surfaces. The stability analysis of FO linear systems using the technique of Root Locus is the main focus of this paper. Procedure to ...
Fresiello Libera L Section of Rome, Institute of Clinical Physiology, National Research Council, Rome - Italy and Nale?cz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Warsaw - - - 2013
Introduction: The aim of this study was to investigate the effects of the intra aortic balloon pump (IABP) and of aortic compliance on left ventricular performance, including the effects of baroreflex control.‚Ä©Methods: The study was conducted using a hybrid cardiovascular simulator, including a computational cardiovascular sub-model, a hydraulic sub-model of ...
Soslow Jonathan H - - 2013
Diagnosing coarctation of the aorta (CoA) in the presence of a patent ductus arteriosus (PDA) may require observation until PDA closure. The aim of this study was to create a model incorporating previously published indices to estimate the probability of neonatal CoA in the presence of a PDA. A retrospective "investigation" ...
Garcia Julio - - 2013
Valve effective orifice area EOA and transvalvular mean pressure gradient (MPG) are the most frequently used parameters to assess aortic stenosis (AS) severity. However, MPG measured by cardiovascular magnetic resonance (CMR) may differ from the one measured by transthoracic Doppler-echocardiography (TTE). The objectives of this study were: 1) to identify ...
Hahn Rebecca T - - 2013
Studies evaluating three-dimensional echocardiographic (3DE) annular sizing for balloon-expandable transcatheter aortic valve replacement (TAVR) are limited. In this study, a retrospective analysis of transesophageal echocardiographic images was performed to assess the feasibility of multiplanar measurements of annular dimensions by the novel off-label use of commercially available 3DE software and correlate ...
Sturla Francesco - - 2013
Numerical modeling can provide detailed and quantitative information on aortic root (AR) biomechanics, improving the understanding of AR complex pathophysiology and supporting the development of more effective clinical treatments. From this standpoint, fluid-structure interaction (FSI) models are currently the most exhaustive and potentially realistic computational tools. However, AR FSI modeling ...
Schlicht M S MS Vascular Mechanics Laboratory, Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA. Electronic address: - - 2013
This study was performed to determine the feasibility of measuring the elastic properties of the arterial wall in vivo. To prove this concept, elastic parameters were calculated from an aortic model of elastic behavior similar to a human aorta using computed tomography angiography (CTA) images. We first constructed an aortic ...
Dangi Siddharth - - 2013
Closed-loop decoder adaptation (CLDA) is an emerging paradigm for improving or maintaining the online performance of brain-machine interfaces (BMIs). Here, we present Likelihood Gradient Ascent (LGA), a novel CLDA algorithm for a Kalman filter (KF) decoder that uses stochastic, gradient-based corrections to update KF parameters during closed-loop BMI operation. LGA's ...
Wang Juan - - 2013
Rooted phylogenetic trees constructed from different datasets (e.g. from different genes) are often conflicting with one another, i.e. they cannot be integrated into a single phylogenetic tree. Phylogenetic networks have become an important tool in molecular evolution, and rooted phylogenetic networks are able to represent conflicting rooted phylogenetic trees. Hence, ...
Mortensen Kristian H - - 2013
BACKGROUND: Identification of the subset females with Turner syndrome (TS) who face especially high risk of aortic dissection is difficult, and more optimal risk assessment is pivotal in order to improve outcomes. This study aimed to provide comprehensive, dynamic mathematical models of aortic disease in Turner syndrome by use of ...
Doshi Krunal A KA Lecturer, Department of Dravyaguna, Institute of Ayurvedic Pharmaceutical Sciences, Jamnagar, Gujarat, - - 2013
In Ayurveda, the roots of Eranda (Ricinus communis Linn.) are used in the treatment Amavata (rheumatism), Sotha (inflammation), Katisula (backache), Udararoga (disease of abdomen), Jwara (fever), etc, Due to high demand, root of the cultivated variety is mainly used in place of wild. But, a comparative phytochemical profile of both ...
Zhao Tingting - - 2013
The policy gradient approach is a flexible and powerful reinforcement learning method particularly for problems with continuous actions such as robot control. A common challenge is how to reduce the variance of policy gradient estimates for reliable policy updates. In this letter, we combine the following three ideas and give ...
Rashedi Mohammad - - 2013
In this paper, we assess the validity of two alternative tube-load models for describing the relationship between central aortic and peripheral arterial blood pressure (BP) waveforms in humans. In particular, a single-tube (1-TL) model and a serially connected two-tube (2-TL) model, both terminated with a Windkessel load, are considered as ...
Roccabianca S - - 2013
There has been a growing awareness over the past decade that stiffening of the aorta, and its attendant effects on hemodynamics, is both an indicator and initiator of diverse cardiovascular, neurovascular, and renovascular diseases. Although different clinical metrics of arterial stiffness have been proposed and found useful in particular situations, ...
García-Herrera Claudio M - - 2013
This work presents the modelling and simulation of the mechanical behaviour of the human aortic arch under in vivo conditions with pressure levels within the normal and hypertension physiological range. The cases studied correspond to young and aged arteries without cardiovascular pathologies. First, the tissue of these two groups is characterised ...
Ehsani Sara - - 2013
Mandibular first molar is the most important tooth with complicated morphology. In finite element (FE) studies, investigators usually prefer to model anterior teeth with a simple and single straight root; it makes the results deviate from the actual case. The most complicated and time-consuming step in FE studies is modeling ...
Bodner Gernot - - 2013
Plant root systems have a key role in ecology and agronomy. In spite of fast increase in root studies, still there is no classification that allows distinguishing among distinctive characteristics within the diversity of rooting strategies. Our hypothesis is that a multivariate approach for "plant functional type" identification in ecology ...
Lai Jiangshan - - 2013
Precise estimation of root biomass is important for understanding carbon stocks and dynamics in forests. Traditionally, biomass estimates are based on allometric scaling relationships between stem diameter and coarse root biomass calculated using linear regression (LR) on log-transformed data. Recently, it has been suggested that nonlinear regression (NLR) is a ...
Venegas-Pino Daniel E DE Department of Biochemistry and Biomedical Sciences, McMaster - - 2013
Atherosclerosis is a disease of the large arteries and a major underlying cause of myocardial infarction and stroke. Several different mouse models have been developed to facilitate the study of the molecular and cellular pathophysiology of this disease. In this manuscript we describe specific techniques for the quantification and characterization ...
Guyot Alexis A King's College London, Division of Imaging Sciences, London, - - 2013
Overlay of preoperative images is increasingly being used to aid complex endovascular aortic repair and is obtained by rigid 2D-3D registration of 3D preoperative (CT) and 2D intraoperative (X-ray) data. However, for tortuous aortas large non-rigid deformations occur, thus a non-rigid registration must be performed to enable an accurate overlay. ...
Itu Lucian - - 2012
We propose a CFD-based approach for the non-invasive hemodynamic assessment of pre- and post-operative coarctation of aorta (CoA) patients. Under our approach, the pressure gradient across the coarctation is determined from computational modeling based on physiological principles, medical imaging data, and routine non-invasive clinical measurements. The main constituents of our ...
Hoshida Yujin - - 2012
Chronic fibrotic liver diseases such as viral hepatitis eventually develop liver cirrhosis, which causes occurrence of hepatocellular carcinoma (HCC). Given the limited therapeutic efficacy in advanced HCC, prevention of HCC development could be an effective strategy for improving patient prognosis. However, there is still no established therapy to meet the ...
Krsmanovic Dejan - - 2012
The objective of this study was to determine the orientation and magnitude of maximal displacement forces (DFs) in the thoracic aortic aneurysm endograft (TAA endograft) in three-dimensional (3D) space. Theoretical computer model representing the anatomically worst-case scenario with respect to DF magnitude was used to calculate the magnitude and orientation ...
Teschke Rolf - - 2012
The aim of this current opinion report is to discuss relevant issues of regulatory causality assessment methods related to initially suspected herb-induced liver injury (HILI). Herbal hepatotoxicity represents a major clinical, regulatory and public challenge since its diagnosis may be difficult to be established, requiring a sophisticated approach that includes ...
Gu Zhidong - - 2012
Mycophenolate Mofetil (MMF) is widely used in preventing acute rejection in liver transplantation. Only free MPA (fMPA) can exert the pharmacological effect. In this study, we aimed to develop the new model which could be best fit to predict the fMPA area under the plasma concentration-time curve (AUC) by limited ...
Howell Brett A - - 2012
Drug-induced liver injury (DILI) is not only a major concern for all patients requiring drug therapy, but also for the pharmaceutical industry. Many new in vitro assays and pre-clinical animal models are being developed to help screen compounds for the potential to cause DILI. This study demonstrates that mechanistic, mathematical ...
Marom Gil - - 2012
A bicuspid aortic valve (BAV) is a congenital cardiac disorder where the valve consists of only two cusps instead of three in a normal tricuspid valve (TAV). Although 97% of BAVs include asymmetric cusps, little or no prior studies investigated the blood flow through physiological three-dimensional BAV and root. This ...
Chang Kai-Hsiang - - 2012
Purpose: Due to low frame rate of MRI and high radiation damage from fluoroscopy and CT, liver motion estimation using external respiratory surrogate signals seems to be a better approach to track liver motion in real-time for liver tumor treatments in radiotherapy and thermotherapy. This work proposes a liver motion ...
May Jennifer E - - 2012
There is an increasing need for development of physiologically relevant in-vitro models for testing toxicity, however determining toxic effects of agents which undergo extensive hepatic metabolism can be particularly challenging. If a source of such metabolic enzymes is inadequate within a model system, toxicity from prodrugs may be grossly underestimated. ...
Leclère Franck Marie P - - 2012
BACKGROUND: Experiments using animal models are the most common way to learn microsurgery. This expertise is necessary for liver research, microsurgical reconstruction of the esophagus by free jejunum or reconstruction of the hepatic artery during reimplantation from living donors. The goal of this prospective study is to assess the reliability ...
Remien Christopher H - - 2012
Acetaminophen (APAP) is the leading cause of acute liver injury in the developed world. Timely administration of N-acetylcysteine (N-Ac) prevents the progression of serious liver injury and disease, whereas failure to administer N-Ac within a critical time frame allows disease progression and in the most severe cases may result in ...
Weiss Michael - - 2012
Objectives:  Up to now, vascular indicator dilution curves have been analyzed by numerical integration or by fitting empirical functions to the data. Here we apply a recently developed mechanistic model with the goal to quantitatively describe flow distribution in the sinusoidal network of normal rat livers and those with high-fat ...
Yang Ju Dong - - 2012
Survival of patients with hepatocellular carcinoma (HCC) is determined by the extent of the tumor and the underlying liver function. We aimed to develop a survival model for HCC based on objective parameters including the Model for Endstage Liver Disease (MELD) as a gauge of liver dysfunction. This analysis is ...
Tulchinsky Mark - - 2012
This study aimed to assess which region of interest results in the best intraobserver reproducibility of mebrofenin clearance rate (MCR) processing. Mebrofenin clearance rate was calculated according to Ekman's formalism. Processing methods included smaller left ventricular (LV) versus larger regions, nearly the whole heart (WH), which were applied to either ...
Cleophas Ton J - - 2012
A major objective of clinical research is to study outcome effects in subgroups. Such effects generally have stepping functions that are not strictly linear. Analyzing stepping functions in linear models thus raises the risk of underestimating the effects. In the past few years, recoding subgroup properties from continuous variables into ...
Martelli Alain - - 2012
Friedreich's ataxia (FRDA) is the most common hereditary ataxia in the caucasian population and is characterized by a mixed spinocerebellar and sensory ataxia, hypertrophic cardiomyopathy and increased incidence of diabetes. FRDA is caused by impaired expression of the FXN gene coding for the mitochondrial protein frataxin. During the past ten ...
Dietrich C F - - 2012
The European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) introduced the first guidelines on the use of contrast-enhanced ultrasound (CEUS) in 2004. This EFSUMB document focused mainly on liver applications. However, new applications extending beyond the liver were subsequently developed. Therefore, in the update of the clinical ...
Wu H - - 2012
Wu, H., Baynes, R. E., Leavens, T., Tell, L. A., Riviere, J. E. Use of population pharmacokinetic modeling and Monte Carlo simulation to capture individual animal variability in the prediction of flunixin withdrawal times in cattle. J. vet. Pharmacol. Therap. doi: 10.1111/j.1365-2885.2012.01420.x. The objective of this study was to develop ...
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