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Morgan M J MJ Max Planck Institute for Neurological Research, PO Box 41 06 29, Cologne 50866, Germany - - 2014
It has been suggested that numerosity is an elementary quality of perception, similar to colour. If so (and despite considerable investigation), its mechanism remains unknown. Here, we show that observers require on average a massive difference of approximately 40% to detect a change in the number of objects that vary ...
Wang Z J ZJ Department of Aerospace Engineering, University of Kansas, 2120 Learned Hall, Lawrence, KS 66045, USA - - 2014
Most forecasts predict an annual airline traffic growth rate between 4.5 and 5% in the foreseeable future. To sustain that growth, the environmental impact of aircraft cannot be ignored. Future aircraft must have much better fuel economy, dramatically less greenhouse gas emissions and noise, in addition to better performance. Many ...
Chopard B B Department of Computer Science, University of Geneva, Geneva, Switzerland - - 2014
We review a methodology to design, implement and execute multi-scale and multi-science numerical simulations. We identify important ingredients of multi-scale modelling and give a precise definition of them. Our framework assumes that a multi-scale model can be formulated in terms of a collection of coupled single-scale submodels. With concepts such ...
Skocik Michael J - - 2014
We review the Hodgkin-Huxley, Izhikevich, and leaky integrate-and-fire neuron models in regular spiking modes solved with the forward Euler, fourth-order Runge-Kutta, and exponential Euler methods and determine the necessary time steps and corresponding computational costs required to make the solutions accurate. We conclude that the leaky integrate-and-fire needs the least ...
Botsikas Diomidis D 1 All authors: Department of Imaging and Medical Information Sciences, Division of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, 1211 Genève 4, - - 2014
OBJECTIVE. The purpose of this study was to determine whether there is added benefit to model-based iterative reconstruction as compared with adaptive statistical iterative reconstruction on low-dose abdominal CT in the clinical context of known or suspected urolithiasis. MATERIALS AND METHODS. Fifty-three consecutive patients (35 men, 18 women; mean [SD] ...
Quek Lake-Ee - - 2014
BackgroundThe decomposition of complex metabolic networks into elementary flux modes (EFMs) provides a useful framework for exploring reaction interactions systematically. Generating a complete set of EFMs for large-scale models, however, is near impossible. Even for moderately-sized models (<400 reactions), existing approaches based on the Double Description method must iterate through ...
Isensee A A 1FiBL - Research Institute of Organic Agriculture,Department of Livestock Sciences,Ackerstr. 113,5070 - - 2014
Body condition scoring is a common tool to assess the subcutaneous fat reserves of dairy cows. Because of its subjectivity, which causes limits in repeatability, it is often discussed controversially. Aim of the current study was to evaluate the impact of considering the cows overall appearance on the scoring process ...
Lash Timothy L TL Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA, Department of Epidemiology and Center for Global Health & Development, Boston University School of Public Health, Boston, MA, USA, Division of Epidemiology and Community Health and Division of Environmental Health Sciences, University of Minnesota School of Public Health, Minneapolis, MN, USA, Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, Canada and Department of Epidemiology and Department of Statistics, University of California Los Angeles, Los Angeles, CA, USA - - 2014
Quantitative bias analysis serves several objectives in epidemiological research. First, it provides a quantitative estimate of the direction, magnitude and uncertainty arising from systematic errors. Second, the acts of identifying sources of systematic error, writing down models to quantify them, assigning values to the bias parameters and interpreting the results ...
Aflakparast Mehran M Laboratory of Systems Biology and Bioinformatics (LBB), Institute of Biochemistry and Biophysics, University of Tehran, Iran. - - 2014
In high-dimensional genome-wide (GWA) data, a key challenge is to detect genomic variants that interact in a nonlinear fashion in their association with disease. Identifying such genomic interactions is important for elucidating the inheritance of complex phenotypes and diseases. In this paper, we introduce a new computational method called Informative ...
Liu Kevin K Department of Mathematics, UCL, Gower Street, London WC1E 6BT, UK - - 2014
Repeated oblique impacts and rebounds of a solid body or bodies on horizontal shallow water are investigated through mathematical modelling. The inclinations from the horizontal are supposed small as the skimming evolves, for a thin typical body shape. The new formulation aimed at improved prediction as well as the background ...
Fischer Mareike M Allan Wilson Centre University of Canterbury Christchurch, New Zealand; Department for Mathematics and Computer Science, Ernst-Moritz-Arndt University Greifswald, - - 2014
Applying a method to reconstruct a phylogenetic tree from random data provides a way to detect whether that method has an inherent bias towards certain tree 'shapes'. For maximum parsimony, applied to a sequence of random 2-state data, each possible binary phylogenetic tree has exactly the same distribution for its ...
Kang Seunghwa S Computational Biology and Bioinformatics Group, Pacific Northwest National Laboratory - - 2014
Biological system behaviors are often the outcome of complex interactions among a very large number of cells and their biotic and abiotic environment. Computational biologists attempt to understand, predict, and manipulate biological system behavior through mathematical modeling and computer simulation. Discrete agent based modeling (in combination with high-resolution grids to ...
Andreadis Ioannis I - - 2014
A Computer Aided Diagnosis (CADx) framework for the diagnosis of clustered microcalcifications (MCs) has already been developed, which is based on the analysis of MCs' morphologies, the shape of the cluster they form and the texture of the surrounding tissue. In this work, we investigate the diagnostic information that the ...
Rodrigues Pedro L PL ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal; Algoritmi Center, School of Engineering, University of Minho, Guimarães, Portugal; DIGARC-Polytechnic Institute of Cávado and Ave, Barcelos, Portugal. Electronic address: - - 2014
Pectus excavatum is the most common deformity of the thorax. Pre-operative diagnosis usually includes Computed Tomography (CT) to successfully employ a thoracic prosthesis for anterior chest wall remodeling. Aiming at the elimination of radiation exposure, this paper presents a novel methodology for the replacement of CT by a 3D laser ...
Plaza Laura L NLP & IR Group, Universidad Nacional de Educación a Distancia (UNED), C/ Juan del Rosal, 16. 28040 Madrid, Spain. Electronic address: - - 2014
Automatic summarization of biomedical literature usually relies on domain knowledge from external sources to build rich semantic representations of the documents to be summarized. In this paper, we investigate the impact of the knowledge source used on the quality of the summaries that are generated. We present a method for ...
Zhang Xuanxuan - - 2014
Dynamic fluorescence molecular tomography (DFMT) is a potential approach for drug delivery, tumor detection, diagnosis and staging. The purpose of DFMT is to quantify the changes of fluorescent agents in the bodies, which offer important information about the underlying physiological processes. However, the conventional method requires that the fluorophore concentrations ...
Pelt Daniel - - 2014
Filtered backprojection, one of the most widely used reconstruction methods in tomography, requires a large number of low-noise projections to yield accurate reconstructions. In many applications of tomography, complete projection data of high quality cannot be obtained, because of practical considerations. Algebraic methods tend to handle such problems better, but ...
Karade Vikas V OrthoCAD Lab, Department of Mechanical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, Maharashtra, India, - - 2014
PURPOSE :    Conventional methods for 3D bone model reconstruction from CT scans can require high-radiation dose, cost and time. A 3D model generated from 2D X-ray images may be a useful alternative. Reconfiguring a 3D template surface mesh model to match bone shape in orthogonal radiographs is a common technique for ...
Haldrup Kristoffer K Centre for Molecular Movies, Department of Physics, Technical University of Denmark, Fysikvej 307, 2800 Kongens Lyngby, Denmark - - 2014
The development of new X-ray light sources, XFELs, with unprecedented time and brilliance characteristics has led to the availability of very large datasets with high time resolution and superior signal strength. The chaotic nature of the emission processes in such sources as well as entirely novel detector demands has also ...
Pazokifard Banafsheh B School of Computer Science and Engineering, University of New South Wales, Sydney, NSW, 2052, Australia, - - 2014
The costal cartilage is a prominent feature of the anterior chest wall that is subject to developmental and acquired abnormalities. A fully automatic algorithm to reconstruct the human costal cartilage from multidetector computed tomography (MDCT) images was developed and tested. The reconstruction algorithm includes three steps: (1) estimation of length, ...
Nakazawa Hisato H Department of Radiological Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daikominami Higashiku, Nagoya, Aichi, 461-8673, Japan, - - 2014
In this study, we assessed the geometric accuracy of an automated positioning system in Gamma Knife (GK) surgery. Specifically, we looked at the total spatial uncertainty over the entire treatment range of GK stereotactic radiosurgery (SRS) procedures in both the GK model C and the Perfexion (PFX). An originally-developed phantom ...
Papagiannis Panagiotis P Medical Physics Laboratory, Medical School, National and Kapodestrian University of Athens, Mikras Asias 75, 115 27 Athens, - - 2014
Following literature contributions delineating the deficiencies introduced by the approximations of conventional brachytherapy dosimetry, different model based dosimetry algorithms have been incorporated to commercial systems for (192)Ir brachytherapy treatment planning. The calculation settings of these algorithms are preconfigured according to criteria established by their developers for optimizing computation speed versus ...
Wellek Stefan - - 2014
Abstract Reference limits are estimators for 'extreme' percentiles of the distribution of a quantitative diagnostic marker in the healthy population. In most cases, interest will be in the 90% or 95% reference intervals. The standard parametric method of determining reference limits consists of computing quantities of the form X̅±c·S. The ...
Rutkowski Leszek - - 2014
In this paper, a new method for constructing decision trees for stream data is proposed. First a new splitting criterion based on the misclassification error is derived. A theorem is proven showing that the best attribute computed in considered node according to the available data sample is the same, with ...
Dufrenois Franck - - 2014
Recently, Dufrenois and Noyer proposed a one class Fisher's linear discriminant to isolate normal data from outliers. In this paper, a kernelized version of their criterion is presented. Originally on the basis of an iterative optimization process, alternating between subspace selection and clustering, I show here that their criterion has ...
Mushthofa Mushthofa M Department of Applied Mathematics, Computer Science and Statistics, Ghent University, Krijgslaan 281 (S9), 9000 Ghent, - - 2014
Boolean network models are suitable to simulate gene regulatory networks (GRNs) in the absence of detailed kinetic information. However, reducing the biological reality implies making assumptions on how genes interact (interaction rules) and how their state is updated during the simulation (update scheme). The exact choice of the assumptions largely ...
Le Thuc Duy - - 2014
microRNAs (miRNAs) are important gene regulators. They control a wide range of biological processes and are involved in several types of cancers. Thus, exploring miRNA functions is important for diagnostics and therapeutics. To date, there are few feasible experimental techniques for discovering miRNA regulatory mechanisms. Alternatively, predictions of miRNA-mRNA regulatory ...
Skrzyński Witold W Department of Medical Physics, Maria Skłodowska-Curie Memorial Cancer Centre and Institute of Oncology, Roentgena 5, 02-781 Warsaw, Poland. Electronic address: - - 2014
The aim of this work was to create a model of a wide-bore Siemens Somatom Sensation Open CT scanner for use with GMCTdospp, which is an EGSnrc-based software tool dedicated for Monte Carlo calculations of dose in CT examinations. The method was based on matching spectrum and filtration to half ...
Schwartz Carolyn E CE DeltaQuest Foundation, Inc, Concord, MA, USA, - - 2014
Missing data due to attrition or item non-response can result in biased estimates and loss of power in longitudinal quality-of-life (QOL) research. The impact of missing data on response shift (RS) detection is relatively unknown. This overview article synthesizes the findings of three methods tested in this special section regarding ...
Dombroski Colin E - - 2014
Custom foot orthoses are currently recognized as the gold standard for treatment of foot and lower limb pathology. While foam and plaster casting methods are most widely used in clinical practice, technology has emerged, permitting the use of 3D scanning, computer aided design (CAD) and computer aided manufacturing (CAM) for ...
Ender Andreas - - 2014
Objective: To investigate the accuracy of conventional and digital impression methods used to obtain full-arch impressions by using an in-vitro reference model. Method and Materials: Eight different conventional (polyether, POE; vinylsiloxanether, VSE; direct scannable vinylsiloxanether, VSES; and irreversible hydrocolloid, ALG) and digital (CEREC Bluecam, CER; CEREC Omnicam, OC; Cadent iTero, ...
Shim Vui Ann - - 2014
Inspired by biological evolution, a plethora of algorithms with evolutionary features have been proposed. These algorithms have strengths in certain aspects, thus yielding better optimization performance in a particular problem. However, in a wide range of problems, none of them are superior to one another. Synergetic combination of these algorithms ...
Wu Jia - - 2014
In this paper, we formulate a novel graph-based learning problem, multi-graph classification (MGC), which aims to learn a classifier from a set of labeled bags each containing a number of graphs inside the bag. A bag is labeled positive, if at least one graph in the bag is positive, and ...
Moradi Mahmoud M Department of Biochemistry, Center for Biophysics and Computational Biology, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United - - 2014
Characterizing large-scale structural transitions in biomolecular systems poses major technical challenges to both experimental and computational approaches. On the computational side, efficient sampling of the configuration space along the transition pathway remains the most daunting challenge. Recognizing this issue, we introduce a knowledge-based computational approach toward describing large-scale conformational transitions ...
Fox Peter T PT Research Imaging Institute - - 2014
Spatial normalization-applying standardized coordinates as anatomical addresses within a reference space-was introduced to human neuroimaging research nearly 30 years ago. Over these three decades, an impressive series of methodological advances have adopted, extended, and popularized this standard. Collectively, this work has generated a methodologically coherent literature of unprecedented rigor, size, ...
Lindhiem Oliver O University of Pittsburgh, Pittsburgh, PA, USA - - 2014
This study adapts the Posterior Probability of Diagnosis (PPOD) Index for use with screening data. The original PPOD Index, designed for use in the context of comprehensive diagnostic assessments, is overconfident when applied to screening data. To correct for this overconfidence, we describe a simple method for adjusting the PPOD ...
Trevisan Diego D Department of Medical Physics, S. Chiara Hospital, APSS Trento, Italy. Electronic address: - - 2014
Overranging or overscanning increases the dose delivered to patients undergoing helical Computed Tomography examinations. In order to reduce it, nowadays most of the multidetector tomographs close the X-ray beam aperture at the scan extremes. This technical innovation, usually referred to as dynamic or adaptive collimation, also influences the overranging assessment ...
Ott Julien G JG Institute of Radiation Physics, Lausanne University Hospital, Rue du Grand-Pré, 1-1007 Lausanne, - - 2014
The state of the art to describe image quality in medical imaging is to assess the performance of an observer conducting a task of clinical interest. This can be done by using a model observer leading to a figure of merit such as the signal-to-noise ratio (SNR). Using the non-prewhitening (NPW) ...
Papafaklis Michail I MI Department of Cardiology, Medical School, University of Ioannina, Ioannina, - - 2014
Aims: To develop a simplified approach of virtual functional assessment of coronary stenosis from routine angiographic data and test it against fractional flow reserve using a pressure wire (wire-FFR). Methods and results: Three-dimensional quantitative coronary angiography (3D-QCA) was performed in 139 vessels (120 patients) with intermediate lesions assessed by wire-FFR ...
Wang Minjue M Key Laboratory of Advanced Control and Optimization for Chemical Processes, Ministry of Education, East China University of Science and Technology, Shanghai, PR - - 2014
P300 and steady-state visual evoked potential (SSVEP) approaches have been widely used for brain-computer interface (BCI) systems. However, neither of these approaches can work for all subjects. Some groups have reported that a hybrid BCI that combines two or more approaches might provide BCI functionality to more users. Hybrid P300/SSVEP ...
Chen Binchao B Level 3 Communications, Broomfield, CO, USA, - - 2014
Compliance to evidenced-base practices, individually and in 'bundles', remains an important focus of healthcare quality improvement for many clinical conditions. The exact probability distribution of composite bundle compliance measures used to develop corresponding control charts and other statistical tests is based on a fairly large convolution whose direct calculation can ...
Aoto Phillip C PC Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, United - - 2014
Non-uniform sampling (NUS) in NMR spectroscopy is a recognized and powerful tool to minimize acquisition time. Recent advances in reconstruction methodologies are paving the way for the use of NUS in quantitative applications, where accurate measurement of peak intensities is crucial. The presence or absence of NUS artifacts in reconstructed ...
Johnson Kevin M KM 1 Department of Diagnostic Radiology, Yale University School of Medicine, 55 Lock St, New Haven, CT - - 2014
OBJECTIVE. The purpose of this article is to present a visual conceptual framework for important statistical concepts in radiology, and to provide an online application to facilitate this visualization. CONCLUSION. Statistical measures such as sensitivity, specificity, and predictive values are ubiquitous in medical literature, yet thinking fluidly about these concepts ...
Romao Joana - - 2014
We present a novel high throughput photocatalyst efficiency assessment method based on 96-well microplates and UV-Vis spectroscopy. We demonstrate the reproducibility of the method using methyl orange (MO) decomposition, and compare kinetic data obtained with those provided in the literature for large conventional photoreactors. To demonstrate the example of the ...
Xi Jinxiang J School of Engineering and Technology, Central Michigan University , Mount Pleasant, MI , USA - - 2014
Abstract Context: How the facial interface affects particle inhalability and depositions within the airway is not well understood. Previous studies of inhalation dosimetry are limited to either inhalability or deposition, rather than the two studied in a systematic way. Objective: To systematically evaluate the effects of the facial interface on ...
Hagler Stuart - - 2014
Early and reliable detection of cognitive decline is one of the most important challenges of current healthcare. In this project, we developed an approach whereby a frequently played computer game can be used to assess a variety of cognitive processes and estimate the results of the pen-and-paper trail making test ...
Nitzken Matthew J - - 2014
The survey outlines and compares popular computational techniques for quantitative description of shapes of major structural parts of the human brain, including medial axis and skeletal analysis, geodesic distances, Procrustes analysis, deformable models, spherical harmonics, and deformation morphometry, as well as other less widely used techniques. Their advantages, drawbacks, and ...
Rajasekaran Sanguthevar S Dept. of Computer Science and Engineering, Univ. of Connecticut, Storrs, CT, - - 2014
The suffix array is a data structure that finds numerous applications in string processing problems for both linguistic texts and biological data. It has been introduced as a memory efficient alternative for suffix trees. The suffix array consists of the sorted suffixes of a string. There are several linear time ...
Papafaklis Michail I MI Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, - - 2014
Aims: To develop a methodology that permits accurate 3-dimensional (3D) reconstruction from FD-OCT and angiographic data enabling reliable evaluation of the ESS distribution, and to compare the FD-OCT-derived models against the established models based on angiography/IVUS. Methods and results: Fifteen patients (17 coronary arteries) who underwent angiography, FD-OCT and IVUS ...
Muegge Ingo I Boehringer Ingelheim Pharmaceuticals, Department of Medicinal Chemistry, 900 Ridgebury Road, Ridgefield, CT 06877-0368, USA. Electronic address: - - 2014
A new method for 3D in silico screening of large virtual combinatorial chemistry spaces is described. The software PharmShape screens millions of individual compounds applying a multi-conformational pharmacophore and shape based approach. Its extension, PharmShapeCC, is capable of screening trillions of compounds from tens of thousands of combinatorial libraries. Key ...
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