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Randtke Edward A EA Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, - - 2014
Magnetic resonance imaging (MRI) contrast media that are detected via chemical exchange saturation transfer (CEST) often require an accurate estimation of their chemical exchange rate, kex . A variety of analysis methods have been proposed to estimate kex , including the nonlinear QUEST analysis method that evaluates the CEST amplitude ...
Tosic Ivana - - 2014
This paper presents a method for learning overcomplete dictionaries of atoms composed of two modalities that describe a 3D scene: 1) image intensity and 2) scene depth. We propose a novel joint basis pursuit (JBP) algorithm that finds related sparse features in two modalities using conic programming and we integrate ...
Feng Dai - - 2014
Various works have used magnetic resonance imaging (MRI) tissue classification extensively to study a number of neurological and psychiatric disorders. Various noise characteristics and other artifacts make this classification a challenging task. Instead of splitting the procedure into different steps, we extend a previous work to develop a unified Bayesian ...
Sarraf Michel M Université Joseph Fourier, Grenoble Institut des Neurosciences, Institut National de la Santé et de la Recherche Médicale INSERM-U836, Bâtiment Edmond J. Safra, Chemin Fortuné Ferrini, Grenoble, France; CLINATEC, Commissariat à l'énergie atomique et aux énergies alternatives, MINATEC Campus, Grenoble, France; Université Saint Joseph-Faculté des sciences, Département de physique, campus des sciences et technologies, Mar Roukos, Mkallès, - - 2014
This study demonstrates how to quantify the tumor blood volume fraction (BVf) using the dynamic Rapid-Steady-State-T1 (RSST1 )-MRI method despite contrast agent (CA) leakage and without arterial input function (AIF) determination. For vasculature impermeable to CAs, the BVf is directly quantified from the RSST1 signal amplitude. In case of CA ...
Macháň Radek R Departments of Biological Sciences and Chemistry and Centre for BioImaging Sciences, National University of Singapore, Singapore 117557, - - 2014
Fluorescence correlation spectroscopy (FCS) is a widely used technique in biophysics and has helped address many questions in the life sciences. It provides important advantages compared to other fluorescence and biophysical methods. Its single molecule sensitivity allows measuring proteins within biological samples at physiological concentrations without the need of overexpression. ...
Alsop David C DC Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, - - 2014
This review provides a summary statement of recommended implementations of arterial spin labeling (ASL) for clinical applications. It is a consensus of the ISMRM Perfusion Study Group and the European ASL in Dementia consortium, both of whom met to reach this consensus in October 2012 in Amsterdam. Although ASL continues ...
Oleszkiewicz Simon - - 2014
This study is on how to elicit intelligence from human sources. We compared the efficacy of two human intelligence gathering techniques: the Scharff-technique (conceptualized as four different tactics) and the Direct Approach (a combination of open and direct questions). Participants (N = 60) were asked to take on the role ...
Sasaki Naoki N Department of Applied Chemistry, Faculty of Science and Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585, Japan; Department of Chemical and Biological Sciences, Faculty of Science, Japan Women's University, 2-8-1 Mejirodai, Bunkyo-ku, Tokyo 112-8681, Japan. Electronic address: - - 2014
We report a microvascular-interstitium model on microfluidic devices to study leakage of drugs from blood vessels under in vivo-like flow conditions. We employed magnetic resonance imaging to demonstrate the compatibility of the model for experimental animals and humans. We observed transport of two types of different molecular-weight contrast agents into ...
Yang Xue - - 2014
Modern statistical inference techniques may be able to improve the sensitivity and specificity of resting state functional magnetic resonance imaging (rs-fMRI) connectivity analysis through more realistic assumptions. In simulation, the advantages of such methods are readily demonstrable. However, quantitative empirical validation remains elusive in vivo as the true connectivity patterns ...
Schwab Felix F Josef Lissner Laboratory for Biomedical Imaging, Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Munich, Germany; Munich Heart Alliance, Munich, - - 2014
To investigate and compare several quantification methods of myocardial perfusion measurements, paying special attention to the relation between the techniques and the required measurement duration. Seven patients underwent contrast-enhanced rest and stress cardiac perfusion measurements at 3T. Three slices were acquired in each patient and were divided into 16 segments, ...
Mertzanidou Thomy T Centre for Medical Image Computing, University College London, Gower Street, WC1E 6BT London, UK. Electronic address: - - 2014
Determining corresponding regions between an MRI and an X-ray mammogram is a clinically useful task that is challenging for radiologists due to the large deformation that the breast undergoes between the two image acquisitions. In this work we propose an intensity-based image registration framework, where the biomechanical transformation model parameters ...
Gilani Hammad H International Centre for Integrated Mountain Development, GPO Box 3226, Kathmandu, Nepal; School of Geomatics, Liaoning Technical University, 47 Zhonghua Road, Fuxin, Liaoning Province, China. Electronic address: - - 2014
Land cover (LC) is one of the most important and easily detectable indicators of change in ecosystem services and livelihood support systems. This paper describes the decadal dynamics in LC changes at national and sub-national level in Bhutan derived by applying object-based image analysis (OBIA) techniques to 1990, 2000, and ...
Becker S M A SM Weierstrass Institute for Applied Analysis and Stochastics, Berlin, - - 2014
We present a novel multi-shell position orientation adaptive smoothing (msPOAS) method for diffusion-weighted magnetic resonance data. Smoothing in voxel and diffusion gradient space is embedded in an iterative adaptive multiscale approach. The adaptive character avoids blurring of the inherent structures and preserves discontinuities. The simultaneous treatment of all q-shells improves ...
Li Hewei H School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, PR - - 2014
Everted gut sac (EGS) and in situ single-pass intestinal perfusion (SPIP) have been widely used in the study of drug absorption and biopharmaceutical classification systems (BCS). Furthermore, they could also be applied in the research of drug intestinal first-pass metabolism. Since most of Chinese herbal medicines (CHMs) are orally administrated, ...
Kramann Rafael R Renal Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, - - 2014
AKI predicts the future development of CKD, and one proposed mechanism for this epidemiologic link is loss of peritubular capillaries triggering chronic hypoxia. A precise definition of changes in peritubular perfusion would help test this hypothesis by more accurately correlating these changes with future loss of kidney function. Here, we ...
Boruah Dibyajyoti D Department of Pathology, Armed Forces Medical College, Pune-411040, Maharashtra, INDIA. Electronic address: - - 2014
Modifications of nuclear morphology in conjunction with alteration in microvascular configuration are essential features encountered during the progression of glial tumours. In order to gain more insight into tumour biology of gliomas, objectives of the study were selected (a) to correlate morphometrically evaluated nuclear parameters [nuclear area (NA), nuclear perimeter ...
Sjögren Erik E Department of Pharmacy, Uppsala University, Uppsala - - 2014
This review summarizes the current knowledge on anatomy and physiology of the human gastrointestinal tract in comparison with that of common laboratory animals (dog, pig, rat and mouse) with emphasis on in vivo methods for testing and prediction of oral dosage form performance. A wide range of factors and methods ...
Feng Meiyan M School of Biomedical Engineering, Southern Medical University, Guangzhou, - - 2014
To evaluate the performance of region-of-interest (ROI)-based MRI R2* measurements by using the first-moment noise-corrected model (M(1)NCM) to correct the non-central Chi noise in magnitude images from phased arrays for hepatic iron content (HIC) assessment. R2* values were quantified using the M(1)NCM model. Three approaches were employed to determine the ...
Bindschadler Michael M Department of Bioengineering University of Washington, Seattle, WA 98195, US. Department of Radiology, University of Washington, Seattle, WA 98195, - - 2014
Myocardial blood flow (MBF) can be estimated from dynamic contrast enhanced (DCE) cardiac CT acquisitions, leading to quantitative assessment of regional perfusion. The need for low radiation dose and the lack of consensus on MBF estimation methods motivates this study to refine the selection of acquisition protocols and models for ...
Tsai Tsung-Hung - - 2014
Camera-enabled mobile devices are commonly used as interaction platforms for linking the user's virtual and physical worlds in numerous research and commercial applications, such as serving an augmented reality interface for mobile information retrieval. The various application scenarios give rise to a key technique of daily life visual object recognition. ...
Schwen Lars Ole LO Fraunhofer MEVIS, Bremen, - - 2014
The liver is the central organ for detoxification of xenobiotics in the body. In pharmacokinetic modeling, hepatic metabolization capacity is typically quantified as hepatic clearance computed as degradation in well-stirred compartments. This is an accurate mechanistic description once a quasi-equilibrium between blood and surrounding tissue is established. However, this model ...
Yi Boram B Department of Radiology, Ajou University School of Medicine, San 5, Woncheon-dong, Yongtong-gu, Suwon, Gyeonggi-do, 442-749, South - - 2014
To find out any correlation between dynamic contrast-enhanced (DCE) model-based parameters and model-free parameters, and evaluate correlations between perfusion parameters with histologic prognostic factors. Model-based parameters (Ktrans, Kep and Ve) of 102 invasive ductal carcinomas were obtained using DCE-MRI and post-processing software. Correlations between model-based and model-free parameters and between ...
Zöllner Frank G FG Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany. Electronic address: - - 2014
To investigate the results of different pharmacokinetic models of a quantitative analysis of renal blood flow (RBF) in acute kidney injury using deconvolution analysis and a two-compartment renal filtration model. MRI data of ten male Lewis rats were analyzed retrospectively. Six animals were subjected to unilateral acute kidney injury and ...
Ramezani Mahdi M Department of Electrical and Computer Engineering, The University of British Columbia, Vancouver, BC, Canada, - - 2014
Classification of individuals based on patterns of brain activity observed in functional MRI contrasts may be helpful for diagnosis of neurological disorders. Prior work for classification based on these patterns have primarily focused on using a single contrast, which does not take advantage of complementary information that may be available ...
Richardson Owen C OC Division of Medical Physics, University of Leeds, Leeds, United - - 2014
There is currently no adequate method of mapping physiologic and pathophysiologic tissue albumin concentrations in human subjects. The objective of this study was to devise and evaluate a biomarker of regional albumin concentration using gadofosveset-enhanced MRI. A binding and relaxation model was devised and evaluated in vitro in solutions of ...
Bartoš Michal M Dept. of Biomedical Engineering, Brno Univ. of Technology, Brno, Czech Republic; Inst. of Information Theory and Automation of the Academy of Sciences of the Czech Republic, Prague, Czech Republic. Electronic address: - - 2014
The present trend in dynamic contrast-enhanced MRI is to increase the number of estimated perfusion parameters using complex pharmacokinetic models. However, less attention is given to the precision analysis of the parameter estimates. In this paper, the distributed capillary adiabatic tissue homogeneity pharmacokinetic model is extended by the bolus arrival ...
Craveiro Mélanie M Laboratory for Functional and Metabolic Imaging, Ecole Polytechnique Fédérale de Lausanne, Lausanne, - - 2014
In (1) H magnetic resonance spectroscopy, macromolecule signals underlay metabolite signals, and knowing their contribution is necessary for reliable metabolite quantification. When macromolecule signals are measured using an inversion-recovery pulse sequence, special care needs to be taken to correctly remove residual metabolite signals to obtain a pure macromolecule spectrum. Furthermore, ...
Georgeson Mark A MA School of Life & Health Sciences, Aston University, Birmingham, - - 2014
(1) To devise a model-based method for estimating the probabilities of binocular fusion, interocular suppression and diplopia from psychophysical judgements, (2) To map out the way fusion, suppression and diplopia vary with binocular disparity and blur of single edges shown to each eye, (3) To compare the binocular interactions found ...
Murray Preston R PR Department of Mechanical Engineering, Brigham Young University, Provo, - - 2014
To design and evaluate a platform for studying the mechanical effects of augmentation injections using synthetic, self-oscillating vocal fold models. Basic science. Life-sized, synthetic, multilayer, self-oscillating vocal fold models were created that simulated bowing via volumetric reduction of the body layer relative to that of a normal, unbowed model. Material ...
Veksler Vladislav D VD Air Force Research - - 2014
Successfully explaining and replicating the complexity and generality of human and animal learning will require the integration of a variety of learning mechanisms. Here, we introduce a computational model which integrates associative learning (AL) and reinforcement learning (RL). We contrast the integrated model with standalone AL and RL models in ...
Fourman Mitchell Stephen MS From the *School of Medicine, †Department of Surgery, and ‡Division of Plastic Surgery, Department of Surgery, Stony Brook University Medical Center, Stony Brook, NY; and §Department of Surgery, Baylor College of Medicine, Houston, - - 2014
The McFarlane rat ischemic dorsal skin flap model has been commonly used for clinical vector studies, as well as the testing of noninvasive diagnostics. However, variability of this model secondary to flap contact with the wound bed has led many to question its validity. Here we present a novel modification ...
Kellman Peter - - 2014
The longitudinal relaxation time constant (T1) of the myocardium is altered in various disease states due to increased water content or other changes to the local molecular environment. Changes in both native T1 and T1 following administration of gadolinium (Gd) based contrast agents are considered important biomarkers and multiple methods ...
Evans Kevin D KD RT, RVS, The Ohio State University, 453 W 10th Ave, Columbus, OH 43210 USA. - - 2014
Objectives- The purpose of this study was to provide clinical evidence of the use of contrast-enhanced sonography in detecting and quantifying changes in intraneural vascularity due to median mononeuropathy. Methods- Five Macaca fascicularis monkeys were exposed to 20 weeks of repetitive work to increase their risk of developing median mononeuropathy. ...
Curren Jane J Environmental Science and Engineering Program and Department of Environmental Health Sciences, School of Public Health, University of California, Los Angeles, CA 90095, USA E-mail: - - 2014
Government agencies responsible for ensuring healthful water and/or air quality are often faced with resolving public complaints of nuisance odors. Understanding variations in odor intensity may ultimately lead to the establishment and application by such agencies of quantitative limits for effective odorant control. An odor panel was trained in suprathreshold ...
Yin Jiandong J Sino-dutch Biomedical and Information Engineering School of Northeastern University, Shenyang, Liaoning, China ; Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, - - 2014
The arterial input function (AIF) plays a crucial role in the quantification of cerebral perfusion parameters. The traditional method for AIF detection is based on manual operation, which is time-consuming and subjective. Two automatic methods have been reported that are based on two frequently used clustering algorithms: fuzzy c-means (FCM) ...
Dzamba Tom T Department of Aerospace Engineering, Ryerson University, 350 Victoria Street, Toronto M5B 2K3, Canada. - - 2014
The performance of a star tracker is largely based on the availability of its attitude solution. Several methods exist to assess star tracker availability under both static and dynamic imaging conditions. However, these methods typically make various idealizations that can limit the accuracy of these results. This study aims to ...
Anthony Neil R NR Department of Physics, Emory University, Atlanta, Georgia, United States of - - 2014
Fluorescence fluctuation methods have become invaluable research tools for characterizing the molecular-level physical and chemical properties of complex systems, such as molecular concentrations, dynamics, and the stoichiometry of molecular interactions. However, information recovery via curve fitting analysis of fluctuation data is complicated by limited resolution and challenges associated with identifying ...
Jackson Alan A Wolfson Molecular Imaging Centre, The University of Manchester, Manchester, United - - 2014
To compare semi-quantitative (SQ) and pharmacokinetic (PK) parameters for analysis of dynamic contrast enhanced MR data (DCE-MRI) and investigate error-propagation in SQ parameters. Clinical data was collected from five patients with type 2-neurofibromatosis (NF2) receiving anti-angiogenic therapy for rapidly growing vestibular schwannoma (VS). There were 7 VS and 5 meningiomas. ...
Wang Hongxin H Department of Chemistry, University of California, 1 Shields Avenue, Davis, CA, 95616, - - 2014
Nuclear resonance vibrational spectroscopy (NRVS) has been used by physicists for many years. However, it is still a relatively new technique for bioinorganic users. This technique yields a vibrational spectrum for a specific element, which can be easily interpreted. Furthermore, isotopic labeling allows for site-specific experiments. In this chapter, we ...
Zhang Qiuwen Q 0000-0002-7023-000X Center for Digital Engineering and Simulation, Huazhong University of Science and Technology, 1037 Luoyu Road, Hongshan District, Wuhan 430074, - - 2014
In recent years, earthquakes have frequently occurred all over the world, which caused huge casualties and economic losses. It is very necessary and urgent to obtain the seismic intensity map timely so as to master the distribution of the disaster and provide supports for quick earthquake relief. Compared with traditional ...
Siganporia Cyrus C CC Department of Biochemical Engineering, University College London, Torrington Place, London, WC1E - - 2013
Production planning for biopharmaceutical portfolios becomes more complex when products switch between fed-batch and continuous perfusion culture processes. This paper describes the development of a discrete-time mixed integer linear programming (MILP) model to optimise capacity plans for multiple biopharmaceutical products, with either batch or perfusion bioprocesses, across multiple facilities to ...
Parhizgari Zahra Z Program of Environmental Applied Science and Management, Ryerson University, Toronto, ON, - - 2013
A Physiologically-Based Pharmacokinetic (PBPK) model was developed for the disposition of 2,3,7,8-TCDD in two fish species, fathead minnow and medaka. The model was developed based on the empirical data on disposition of dioxins in fish tissues, as well as existing knowledge on the mechanisms of uptake, distribution, storage and elimination ...
Guay Jean-Maxime JM Pfizer Industrial Research Chair on PAT in Pharmaceutical Engineering, Department of Chemical & Biotechnological Engineering, Université de Sherbrooke, Sherbrooke, Quebec, Canada; Process Analytical Science Group, Global Technology Services, Pfizer Canada, St-Laurent, Quebec, - - 2013
Process analytical technologies (PAT) enable process insight, process control and real-time testing. Light-induced fluorescence (LIF) spectroscopy is especially well suited for low-concentration ingredients as, in many cases, it is the most sensitive probe of the in-line PAT toolbox. This study is aimed at verifying the applicability of a multivariate LIF ...
Ooi Jesslynn - - 2013
The purpose of this work was to evaluate gas perfusion isothermal calorimetry (ITC) as a method to characterize the physicochemical changes of active pharmaceutical ingredients (APIs) intended to be formulated in pressurised metered dose inhalers (pMDIs) after exposure to a model propellant. Spray dried samples of beclomethasone dipropionate (BDP) and ...
Epple F M - - 2013
We present a spectral phase unwrapping approach for grating-based differential phase-contrast data where the unwrapped interferometer phase shift is estimated from energy discriminated measurements using maximum likelihood principles. We demonstrate the method on tomographic data sets of a test specimen taken at different x-ray energies using synchrotron radiation. The proposed ...
Hu Sijung - - 2013
This paper presents opto-physiological (OP) modeling and its application in cardiovascular assessment techniques based on photoplethysmography (PPG). Existing contact point measurement techniques, i.e., pulse oximetry probes, are compared with the next generation non-contact and imaging implementations, i.e., non-contact reflection and camera-based PPG. The further development of effective physiological monitoring techniques ...
Mathiesen Line L Department of Public Health, University of Copenhagen, - - 2013
Human exposure to parabens as a preservative used in personal care products is of increasing concern, as there is evidence from in vivo and in vitro studies of hormone disruption in association with exposure to parabens. Transport across the placenta could be critical for risk assessment, but the available data ...
Anderson Stephan W - - 2013
To employ the stretched exponential and diffusional kurtosis models to study the non-Gaussian behavior of diffusion-related signal decay of the liver in an animal model of hepatic fibrosis. High b-value diffusion imaging data (up to 3500 s/mm(2) ) of ex vivo murine liver specimens was acquired using a 9.4 T ...
Qiu Zhongfeng - - 2013
Distribution of the suspended particulate matter (SPM) concentration is a key issue for analyzing the deposition and erosion variety of the estuary and evaluating the material fluxes from river to sea. Satellite remote sensing is a useful tool to investigate the spatial variation of SPM concentration in estuarial zones. However, ...
Liang Xiaoyun - - 2013
Human connectome mapping is important to understand both normal brain function and disease-related dysfunction. Although blood-oxygen-level-dependent (BOLD) fMRI has been the most commonly used method for human connectome mapping, arterial spin labeling (ASL) is an fMRI technique to measure cerebral blood flow (CBF) directly and noninvasively, and thus provides a ...
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