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Siefert Andrew W AW The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, - - 2014
Computational models of the heart's mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical annuloplasty repair. Towards this goal, a ground-truth data ...
Parra-Robles Juan J Unit of Academic Radiology, University of Sheffield, United Kingdom. Electronic address: - - 2013
Our extensive investigation of the cylinder model theory through numerical modelling and purpose-designed experiments has demonstrated that it does produce inaccurate estimates of airway dimensions at all diffusion times currently used. This is due to a variety of effects: incomplete treatment of non-Gaussian effects, finite airway size, branching geometry, background ...
Boyce Christopher M CM Department of Chemical Engineering and Biotechnology, University of Cambridge , New Museums Site, Pembroke Street, Cambridge CB2 3RA, - - 2013
Discrete element modeling is being used increasingly to simulate flow in fluidized beds. These models require complex measurement techniques to provide validation for the approximations inherent in the model. This paper introduces the idea of modeling the experiment to ensure that the validation is accurate. Specifically, a 3D, cylindrical gas-fluidized ...
Oeffner Robert D - - 2013
The estimate of the root-mean-square deviation (r.m.s.d.) in coordinates between the model and the target is an essential parameter for calibrating likelihood functions for molecular replacement (MR). Good estimates of the r.m.s.d. lead to good estimates of the variance term in the likelihood functions, which increases signal to noise and ...
Siefert Andrew William - - 2013
Computational models for the heart's mitral valve (MV) exhibit several uncertainties that may be reduced by further developing these models using ground-truth data-sets. This study generated a ground-truth data-set by quantifying the effects of isolated mitral annular flattening, symmetric annular dilatation, symmetric papillary muscle (PM) displacement and asymmetric PM displacement ...
Yin Zi - - 2013
A blue colour can be formed in the xylose (Xyl) and glycine (Gly) Maillard reaction (MR) model system. However, there are fewer studies on the reaction conditions for the blue Maillard reaction products (MRPs). The objective of this study is to investigate characteristic colour formation and antioxidant activities in four ...
Mealing Stuart - - 2013
Abstract Objectives: To evaluate the cost-effectiveness of MitraClip, an interventional procedure for patients with chronic severe mitral regurgitation. Methods: A decision analytic model with a lifetime horizon was developed to assess the cost-effectiveness of MitraClip versus conventional medical management in patients with severe mitral regurgitation, ineligible for surgery. The analysis ...
Rim Yonghoon Y Division of Cardiovascular Medicine, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, - - 2013
Most surgical procedures for patients with mitral regurgitation (MR) focus on optimization of annular dimension and shape utilizing ring annuloplasty to restore normal annular geometry, increase leaflet coaptation, and reduce regurgitation. Computational studies may provide insight on the effect of annular motion on mitral valve (MV) function through the incorporation ...
Siefert Andrew W AW The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA. - - 2013
This study was undertaken to evaluate an in vitro mitral valve (MV) simulator's ability to mimic the systolic leaflet coaptation, regurgitation, and leaflet mechanics of a healthy ovine model and an ovine model with chronic ischemic mitral regurgitation (IMR). Mitral valve size and geometry of both healthy ovine animals and ...
Mandava Pitchaiah P The Michael E. DeBakey Veterans Affairs Medical Center Comprehensive Stroke Program, Houston, Texas, USA. - - 2013
Clinical trial outcomes often involve an ordinal scale of subjective functional assessments but the optimal way to quantify results is not clear. In stroke, the most commonly used scale, the modified Rankin Score (mRS), a range of scores ("Shift") is proposed as superior to dichotomization because of greater information transfer. ...
Fuster-Garcia Elies - - 2012
The current challenge in automatic brain tumor classification based on MRS is the improvement of the robustness of the classification models that explicitly account for the probable breach of the independent and identically distributed conditions in the MRS data points. To contribute to this purpose, a new algorithm for the ...
Bolzoni P - - 2012
We present a new approach to consider and include both the perturbative and the nonperturbative contributions to the multiplicities of gluon and quark jets. Thanks to this new method, we have included for the first time new contributions to these quantities obtaining next-to-next-to-leading-logarithmic resummed formulas. Our analytic expressions depend on ...
Moraldo Michela - - 2012
BACKGROUND: Guidelines for quantifying mitral regurgitation (MR) using "proximal isovelocity surface area" (PISA) instruct operators to measure the PISA radius from valve orifice to Doppler flow convergence "hemisphere". Using clinical data and a physically-constructed MR model we (A) analyse the actually-observed colour Doppler PISA shape and (B) test whether instructions ...
Pierce Brandon L - - 2012
Mendelian randomization (MR) studies assess the causality of associations between exposures and disease outcomes using data on genetic determinants of the exposure. In this work, we explore the effect of exposure and outcome measurement error in MR studies. For continuous traits, we describe measurement error in terms of a theoretical ...
Holland Barbara R - - 2012
In their 2008 and 2009 papers, Sumner and colleagues introduced the "squangles" - a small set of Markov invariants for phylogenetic quartets. The squangles are consistent with the general Markov model (GM) and can be used to infer quartets without the need to explicitly estimate all parameters. As GM is ...
Sivaganesan Ahilan - - 2012
: Although it has become possible to collect many physiological measurements in the Neurointensive Care Unit, much of a patient's cerebral physiology or "intracranial state" is still not measurable. We present a computational model of cerebrovascular dynamics that can be used to estimate "hidden," but clinically important, variables using routinely ...
Dürr S - - 2012
Classical swine fever (CSF) outbreaks can cause enormous losses in naïve pig populations. How to best minimize the economic damage and number of culled animals caused by CSF is therefore an important research area. The baseline CSF control strategy in the European Union and Switzerland consists of culling all animals ...
Leroux Aurelia A - - 2012
Mitral regurgitation (MR) is a common valvular disease throughout the world. Various diagnostic techniques have been developed to assess the causes and severity of MR, and the therapeutic approaches to this disease have been widely documented. However, treatments for chronic MR remain controversial, and various animal models of chronic MR ...
Jones Angela M - - 2012
Background: Visual estimation (VE) and goniometric measurement (GM) are commonly used to assess first metatarsophalangeal joint dorsiflexion. The purposes of this study were to determine the intrarater and interrater reliability of VE and GM and to establish whether reliability was influenced by the experience of the examiner. Methods: Ten experienced ...
Hyde Damon E - - 2012
Electromagnetic source localization (ESL) provides non-invasive evaluation of brain electrical activity for neurology research and clinical evaluation of neurological disorders such as epilepsy. Accurate ESL results are dependent upon the use of patient specific models of bioelectric conductivity. While the effects of anisotropic conductivities in the skull and white matter ...
Czeiter Endre - - 2012
Outcome prediction following severe traumatic brain injury (sTBI) is a widely investigated field of research. A major breakthrough is represented by the IMPACT prognostic calculator based on admission data of more than 8500 patients. A growing body of scientific evidence has shown that clinically meaningful biomarkers, including glial fibrillary acidic ...
Tai Leon M - - 2012
Inhibition of the enzyme(s) that produce the Amyloid beta (Aβ) peptide, namely BACE and γ-secretase, is considered an attractive target for Alzheimer's disease therapy. However, the optimal pharmacokinetic-pharmacodynamic modelling method to describe the changes in Aβ levels after drug treatment is unclear. In this study, turnover models were employed to ...
Kang Ju-Hee - - 2012
The xMAP-Luminex multiplex platform for measurement of Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers using Innogenetics AlzBio3 immunoassay reagents that are for research use only has been shown to be an effective tool for early detection of an AD-like biomarker signature based on concentrations of CSF Aβ(1-42), t-tau and p-tau(181). ...
Smolinska Agnieszka - - 2012
Because cerebrospinal fluid (CSF) is the biofluid which interacts most closely with the central nervous system, it holds promise as a reporter of neurological disease, for example multiple sclerosis (MScl). To characterize the metabolomics profile of neuroinflammatory aspects of this disease we studied an animal model of MScl-experimental autoimmune/allergic encephalomyelitis ...
Bottan S - - 2012
We describe herein a novel life-size phantom model of the intracranial cavity and its validation. The cerebrospinal fluid (CSF) domains including ventricular, cysternal and subarachnoid spaces were derived via magnetic resonance imaging (MRI). Brain mechanical properties and cranio-spinal compliance were set based on published data. Both bulk and pulsatile physiologic ...
Gravel Patricia - - 2012
Biosimilars are more affordable copycat versions of originator biological products in much the same way as generics are copies of small molecule pharmaceuticals. However, while generics are approved on the basis of structural and pharmacokinetic equivalence, the intricate structure of biological medicinal products and the complex nature of their manufacturing ...
Collet Nicolas - - 2012
BACKGROUND: Diagnosis of subarachnoid haemorrhage (SAH) is firstly based on imaging and secondly on spectrophotometry. Bilirubin may be detected in the cerebrospinal fluid (CSF) for up to two weeks after SAH. CSF pigment analysis is commonly performed according to the Chalmers manual technique but may be prone to operator error. ...
Foulquier Elodie - - 2012
Bacteria are able to adapt to nutrient availability in the environment. For example, when nutritional conditions are not favorable, bacterial size can be reduced and duplication time can be significantly extended in comparison to rich growth conditions. These observations suggest that essential cellular processes like cell division, morphogenesis and chromosome ...
Luykx Jurjen J - - 2012
Animal studies have revealed seasonal patterns in cerebrospinal fluid (CSF) monoamine (MA) turnover. In humans, no study had systematically assessed seasonal patterns in CSF MA turnover in a large set of healthy adults. Standardized amounts of CSF were prospectively collected from 223 healthy individuals undergoing spinal anesthesia for minor surgical ...
Scholz Markus - - 2012
The human granulocyte colony-stimulating factor (G-CSF) is routinely applied to support recovery of granulopoiesis during the course of cytotoxic chemotherapies. However, optimal use of the drug is largely unknown. We showed in the past that a biomathematical compartment model of human granulopoiesis can be used to make clinically relevant predictions ...
Pawlowski Marcin - - 2012
Computational models of protein structures were proved to be useful as search models in Molecular Replacement (MR), a common method to solve the phase problem faced by macromolecular crystallography. The success of MR depends on the accuracy of a search model. Unfortunately, this parameter remains unknown until the final structure ...
Bate Andrew M - - 2011
Biological invasions often damage island ecosystems. One such damaging consequence of biological invasions is hyperpredation. Hyperpredation is the increase in predation pressure from a generalist predator following the introduction of an alternative prey, typically a consequence of apparent competition between the two prey. Models for this have been devised that ...
Lila Mary Ann - - 2011
Abstract Two different strategies for investigating the likely fate, after ingestion, of natural, bioactive berry constituents (anthocyanins and other non-nutritive flavonoids) are compared. A model of the human gastrointestinal tract (TIM-1) which mimicked the biological environment from the point of swallowing and ingestion through the duodenum, jejunum, and ileum (but ...
Li Yan - - 2011
In population-based household surveys, for example, the National Health and Nutrition Examination Survey (NHANES), blood-related individuals are often sampled from the same household. Therefore, genetic data collected from national household surveys are often correlated due to two levels of clustering (correlation) with one induced by the multistage geographical cluster sampling, ...
Cohu Stéphanie - - 2011
To study environment characteristics favoring the toxic benthic dinoflagellate Ostreopsis cf. ovata, a survey was conducted in Monaco (NW Mediterranean Sea), in summers 2007 and 2008. Epiphytic and planktonic blooms occurred almost simultaneously and a high variation of abundances at low spatial scales was observed. An early and very marked ...
McNamara J P - - 2011
The role of the dairy cow is to help provide high quality protein and other nutrients for humans. We must select and manage cows with the goal of reaching the highest possible efficiency for any given environment. We have increased efficiency tremendously over the years, yet the variation in productive ...
Elias Carol F - - 2012
In recent years we have witnessed a considerable advance in the understanding of the processes involved in pubertal development. This is partially due to the discovery of the kisspeptin system and its fundamental role in the control of reproductive physiology. In addition, the suspected relationship between increasing rates of childhood ...
Gardner Benjamin - - 2011
Health behaviour models typically neglect habitual action. The Self-Report Habit Index (SRHI) permits synthesis of evidence of the influence of habit on behaviour. The purpose of this study is to review evidence around mean habit strength, habit-behaviour correlations, and habit x intention interactions, from applications of the SRHI to dietary, ...
Micha R - - 2012
Global burdens of cardiovascular disease (CVD), diabetes and cancer are on the rise. Little quantitative data are available on the global impact of diet on these conditions. The objective of this study was to develop systematic and comparable methods to quantitatively assess the impact of suboptimal dietary habits on CVD, ...
Elia Marinos - - 2011
Nutrition screening tool selection can be difficult. This review critically examines the relevance of validity, specifically concurrent (agreement between tools) and predictive validity (prediction of outcomes), which have been the focus of several recent studies. An operational framework for screening tool selection is provided to contextualise the findings. Studies of ...
Segarra Alfonso - - 2011
A specific method is required for estimating glomerular filtration rate GFR in hospitalized patients. Our objective was to validate the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation and four cystatin C (CysC)-based equations in this setting. This was an epidemiologic, cross-sectional study in a random sample of hospitalized patients (n ...
Claes Ingmar J J - - 2011
In inflammatory bowel diseases (IBD), it is known that besides genetic and environmental factors (e.g. diet, drugs, stress), the microbiota play an important role in the pathogenesis. Patients with IBD have an altered microbiota (dysbiosis) and therefore, probiotics, defined as 'live micro-organisms that when administered in adequate amounts can confer ...
Evans Tim J - - 2011
This article discusses reproductive toxicants as the potential, primary causes of observed reproductive abnormalities and other variables that can affect reproductive performance in ruminants. The causes of diminished reproductive performance in ruminants are often multifactorial. It is critical that producers and their veterinarians understand the potential effects of physiologic and ...
Jeanne Robert L - - 2011
Specialization into reproductive and non-reproductive castes is one of the defining traits of eusocial insects. Knowledge of the proximal causes of caste differentiation is therefore central to achieving an understanding of the evolution of eusociality. Castes are an example of a polyphenism, multiple, discrete phenotypes arising from a single genotype ...
Garrett Dean A - - 2011
Whereas cost-effective interventions exist for the control of micronutrient malnutrition (MN), in low-resource settings field-friendly tools to assess the effect of these interventions are underutilized or not readily available where they are most needed. Conventional approaches for MN measurement are expensive and require relatively sophisticated laboratory instrumentation, skilled technicians, good ...
Freedman Laurence S - - 2011
Dietary measurement error creates serious challenges to reliably discovering new diet-disease associations in nutritional cohort studies. Such error causes substantial underestimation of relative risks and reduction of statistical power for detecting associations. On the basis of data from the Observing Protein and Energy Nutrition Study, we recommend the following approaches ...
Zhang Saijuan - - 2011
In the United States the preferred method of obtaining dietary intake data is the 24-hour dietary recall, yet the measure of most interest is usual or long-term average daily intake, which is impossible to measure. Thus, usual dietary intake is assessed with considerable measurement error. Also, diet represents numerous foods, ...
Alberti Gerd - - 2011
Oribatida are one of the main groups of Acari comprising mostly important decomposers in soils. Most species are particle feeders, an exceptional mode of nutrition in Arachnida. Hence, their feeding organs, the gnathosoma, are of special functional interest. We studied nearly all components using scanning and transmission electron microscopies as ...
Pesti G M - - 2011
Nutritional requirements are typically estimated based on feeding trials with animals or birds offered several levels of the critical nutrient(s). A nutrient response function is then fitted to data from the feeding trials. Modern computer techniques allow for a variety of functional forms to be used as nutrient response functions. ...
Peterson Theresa C - - 2011
TNBS-induced colitis has characteristics resembling human Crohn's disease including transmural inflammation, ulceration, and fibrosis. Current treatments target acute symptoms but do not necessarily prevent fibrotic complications of the disease. The aim of this study was to determine the effect of pentoxifylline and its primary metabolite (M-1) on fibrosis in the ...
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