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Thai Thanh Hai - - 2014
The goal of this paper is to propose a statistical model of quantized discrete cosine transform (DCT) coefficients. It relies on a mathematical framework of studying the image processing pipeline of a typical digital camera instead of fitting empirical data with a variety of popular models proposed in this paper. ...
Davis Ryan - - 2014
Costs, emissions, and resource availability were modeled for the production of 5 billion gallons per yr (5 BGY) of renewable diesel in the United States from Chlorella biomass by hydrothermal liquefaction (HTL). The HTL model utilized data from a continuous 1-L reactor including catalytic hydrothermal gasification of the aqueous phase, ...
Dou Xiaoling X The Institute of Statistical Mathematics, Research Organization of Information and Systems, 10-3 Midori-cho, Tachikawa, Tokyo, 190-8562, - - 2014
This paper presents systematic methods for the detection of influential individuals that affect the log odds (LOD) score curve. We derive general formulas of influence functions for profile likelihoods and introduce them into two standard quantitative trait locus detection methods-the interval mapping method and single marker analysis. Besides influence analysis ...
Kameyama Masashi M Division of Nuclear Medicine, Department of Radiology, School of Medicine, Keio University, 35, Shinanomachi, Shinjuku-ku, Tokyo 160-8582, - - 2014
Brain perfusion tracers like [(99m)Tc] d,l-hexamethyl-propyeneamine oxime ((99m)Tc-HMPAO) and [(99m)Tc] ethyl-cysteinate dimer ((99m)Tc-ECD) underestimate regional cerebral blood flow (rCBF) at high flow values. To improve linearity between tracer accumulation and rCBF, two different models have been proposed. One is Lassen's correction algorithm for back-diffusion of tracer, and the other is ...
Wang Heng - - 2014
A copy number variation (CNV) is a difference between genotypes in the number of copies of agenomic region. Next generation sequencing (NGS) technologies provide sensitive and accuratetools for detecting genomic variations that include CNVs. However, statistical approaches for CNVidentification using NGS are limited. We propose a new methodology for detecting ...
Evers Eric G EG Centre for Zoonoses and Environmental Microbiology, National Institute for Public Health and the Environment, Bilthoven, The - - 2014
The significance of petting zoos for transmission of Campylobacter to humans and the effect of interventions were estimated. A stochastic QMRA model simulating a child or adult visiting a Dutch petting zoo was built. The model describes the transmission of Campylobacter in animal feces from the various animal species, fences, ...
Malagoli Philippe P Clermont Universités, Université Blaise Pascal, UMR 547 PIAF, BP 10448, F-63000 Clermont Ferrand, - - 2014
Background and AimsAn updated version of a mechanistic structural-functional model was developed to predict nitrogen (N) uptake throughout the growth cycle by a crop of winter oilseed rape, Brassica napus, grown under field conditions.MethodsThe functional component of the model derives from a revisited conceptual framework that combines the thermodynamic Flow-Force ...
Zhang Zheng Z a Department of Biostatistics and Center for Statistical Sciences , Brown University , Providence , RI - - 2014
Abstract The commonly used statistical measures for assessing agreement of readings generated by multiple observers or raters, such as intraclass correlation coeffcient (ICC) or concordance correlation coeffcient (CCC), have well-known dependency on the data's normality assumption, hereby are heavily influenced by data outliers. Here we propose a novel agreement measure(rank-based ...
Kim Su Jin SJ Yale PET Center, Yale University, New Haven, Connecticut; Department of Diagnostic Radiology, Yale University, New Haven, - - 2014
The "linear parametric neurotransmitter PET" (lp-ntPET) model estimates time variation in endogenous neurotransmitter levels from dynamic PET data. The pattern of dopamine (DA) change over time may be an important element of the brain's response to addictive substances such as cigarettes or alcohol. We have extended the lp-ntPET model from ...
Liu Dan D Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, United - - 2014
To analyze the kinetics of 3(')-deoxy-3(')-[F-18]-fluorothymidine (18F-FLT) uptake by head and neck squamous cell carcinomas and involved nodes imaged using positron emission tomography (PET). Two- and three-tissue compartment models were fitted to 12 tumor time-activity-curves (TACs) obtained for 6 structures (tumors or involved nodes) imaged in ten dynamic PET studies ...
Peng Jialin J Department of Computer Science and Technology, Huaqiao University, Xiamen 361021, - - 2014
Liver segmentation from computed tomography images is a challenging task owing to pixel intensity overlapping, ambiguous edges, and complex backgrounds. The authors address this problem with a novel active surface scheme, which minimizes an energy functional combining both edge- and region-based information. In this semiautomatic method, the evolving surface is ...
Chang Jia-Ming JM Comparative Bioinformatics, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, - - 2014
Multiple sequence alignment (MSA) is a key modeling procedure when analyzing biological sequences. Homology and evolutionary modeling are the most common applications of MSAs. Both are known to be sensitive to the underlying MSA accuracy. In this work we show how this problem can be partly overcome using the transitive ...
Szirmay-Kalos Laszlo - - 2014
This paper proposes the application of multiple importance sampling in fully 3-D positron emission tomography to speed up the iterative reconstruction process. The proposed method combines the results of lines of responses (LOR) driven and voxel driven projections keeping their advantages, like importance sampling, performance and parallel execution on graphics ...
Zhu Wentao - - 2014
We investigate using dual time-point PET data to perform Patlak modeling. This approach can be used for whole body dynamic PET studies in which we compute voxel-wise estimates of Patlak parameters using two frames of data for each bed position. Our approach directly uses list-mode arrival times for each event ...
Tax Chantal M W CM Image Sciences Institute, University Medical Center Utrecht, Utrecht, The - - 2014
Recent literature shows that diffusion tensor properties can be estimated more accurately with diffusion kurtosis imaging (DKI) than with diffusion tensor imaging (DTI). Furthermore, the additional non-Gaussian diffusion features from DKI can be sensitive markers for tissue characterization. Despite these benefits, DKI is more susceptible to data artifacts than DTI ...
Giaginis Constantinos C 1Department of Food Science and Nutrition, School of Environment, University of the Aegean, Mitropoliti Ioakeim 2 Street, Myrina, Lemnos GR 81400, - - 2014
Postmortem redistribution (PMR) constitutes a multifaceted process, which complicates the interpretation of drug concentrations by forensic toxicologists. The present study aimed to apply quantitative structure-activity relationship (QSAR) analysis for modeling PMR data of structurally related drugs, 10 benzodiazepines and 10 tricyclic antidepressants. For benzodiazepines, an adequate QSAR model was obtained ...
Williams Jenny J Department of Economics, University of Melbourne, Australia. Electronic address: - - 2014
A key question in the ongoing policy debate over cannabis' legal status is whether liberalizing cannabis laws leads to an increase in cannabis use. This paper provides new evidence on the impact of a specific type of liberalization, decriminalization, on initiation into cannabis use. Our identification strategy exploits variation in ...
Altmann Yoann - - 2014
This paper presents a nonlinear mixing model for hyperspectral image unmixing. The proposed model assumes that the pixel reflectances are post-nonlinear functions of unknown pure spectral components contaminated by an additive white Gaussian noise. These nonlinear functions are approximated using second-order polynomials leading to a polynomial post-nonlinear mixing model. A ...
Pei Mengchao M Shanghai Key Laboratory of Magnetic Resonance and Department of Physics, East China Normal University, Shanghai, China; Yifu Inc, Jiaxing, Zhejiang Province, - - 2014
To develop a fast and accurate monoexponential fitting algorithm based on Auto-Regression on Linear Operations (ARLO) of data, and to validate its accuracy and computational speed by comparing it with the conventional Levenberg-Marquardt (LM) and Log-Linear (LL) algorithms. ARLO, LM, and LL performances for T2* mapping were evaluated in simulation ...
Grote Rüdiger R Institute for Advanced Sustainability Studies (IASS), Berliner Str. 130, 14467 Potsdam, Germany; Karlsruhe Institute for Technology, Institute for Meteorology and Climate Research (IMK-IFU), Kreuzeckbahnstraße 19, 82467 Garmisch-Partenkirchen, - - 2014
The lack of a mechanistic basis has hampered modelling isoprene emission responses to environmental drivers, in particular the simulation of isoprene emissions under different CO2 concentrations. Here, we advance previous semi-mechanistic model formulations by introducing a model that explicitly links electron availability for other purpose than carbon assimilation (or available ...
Liang Yirui - - 2014
Phthalate emission from vinyl floorings was measured in specially-designed stainless steel chambers. Phthalate concentrations increased and reached steady state after 2 to 5 days for all experiments. By having a high ratio of emission surface to sorption surface, avoiding mass loss of phthalates onto sampling pathways, and improving air mixing ...
Sil Avick A Council of Scientific and Industrial Research-National Environmental Engineering Research Institute (CSIR-NEERI), Mumbai Zonal Laboratory, 89/B, Dr. Annie Besant Road, Worli, Mumbai 400018, Maharashtra, - - 2014
Methane emission from landfill gas emission (LandGEM) model was validated through the results of laboratory scale biochemical methane potential assay. Results showed that LandGEM model over estimates methane (CH4) emissions; and the true CH4 potential of waste depends on the level of segregation. Based on these findings, correction factors were ...
Tuna Uygar U Department of Signal Processing and BioMediTech, Tampere University of Technology, P.O. Box 533, 33101 , Tampere, Finland, - - 2014
The aim of the study was (1) to evaluate the reconstruction strategies with dynamic [[Formula: see text]]-raclopride human positron emission tomography (PET) studies acquired from ECAT high-resolution research tomograph (HRRT) scanner and (2) to justify for the selected gap-filling method for analytical reconstruction with simulated phantom data. A new transradial ...
Neumann Daniel D Research Center Magnetic Resonance Bavaria (MRB), Am Hubland, 97074, Würzburg, Germany, - - 2014
The quantification of magnetic resonance relaxation parameters T 1 and T 2 have the potential for improved disease detection and classification over standard clinical weighted imaging. Performing a mono-exponential fit on multi spin-echo (MSE) data provides quantitative T 2 values in a clinically acceptable scan-time. However, due to technical imperfections ...
Halter E E CEA, List, Laboratoire National Henri Becquerel (LNE-LNHB), 91191 Gif-sur-Yvette Cedex, France; CEA, List, Laboratoire Capteurs et Architectures Electroniques, 91191 Gif-sur-Yvette Cedex, - - 2014
Developed for radionuclide standardization using liquid scintillation, the Triple to Double Coincidence Ratio (TDCR) method is applied using coincidence counting obtained with a specific three-photomultiplier system. For activity determination, a statistical model of light emission is classically used to establish a relation between the detection efficiency and the experimental TDCR ...
Le Deunff Erwan E Université de Caen Basse-Normandie, UMR EVA, F-14032 Caen cedex, - - 2014
Background and AimsIn spite of major breakthroughs in the last three decades in the identification of root nitrate uptake transporters in plants and the associated regulation of nitrate transport activities, a simplified and operational modelling approach for nitrate uptake is still lacking. This is due mainly to the difficulty in ...
Yoshida Hiroko H Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark. Electronic address: - - 2014
A Life Cycle Assessment (LCA) of a municipal wastewater treatment plant (WWTP) was conducted to illustrate the effect of an emission inventory data collection scheme on the outcomes of an environmental impact assessment. Due to their burden in respect to data collection, LCAs often rely heavily on existing emission and ...
Zimmer Eduardo Rigon - - 2014
Hypherphosphorylation of the tau protein leading to the formation of neurofibrillary tangles (NFTs) is a common feature in a wide range of neurodegenerative diseases known as tauopathies, which include Alzheimer's disease (AD) and the frontotemporal dementias (FTDs). Although heavily investigated, the mechanisms underlying the pathogenesis and progression of tauopathies has ...
Ren Tianlong T Digital Image and Intelligent computation Laboratory, College of Information Engineering, Shanghai Maritime University, Shanghai 201306, - - 2014
Clustering analysis has been widely used to detect the functional connectivity from functional magnetic resonance imaging (fMRI) data. However, it has some limitations such as enormous computer memory requirement, and difficulty in estimating the number of clusters. In this study, in order to effectually resolve the deficiencies mentioned above, we ...
De Lara Michel M CERMICS (ENPC), Université Paris-Est, 6-8 Avenue Blaise Pascal, Cité Descartes, 77455, Marne-la-Vallée, France, - - 2014
Economic analysis addresses risk and long-term issues with discounted expected utility, focusing on optimality. Viability theory is rooted on satisfying sustainability constraints over time, focusing on feasibility. We build a bridge between these two approaches by establishing that viability is equivalent to an array of degenerate intertemporal optimization problems. First, ...
Wang Chao C School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072, People's Republic of - - 2014
The continuous monitoring of the changing process is an important application field of electrical tomography (ET). In this changing process, the size, position and shape of measured objects are always alterative. The trackability of algorithms to the change of measured objects is important to the application of ET. The single ...
Bikker J P JP Animal Nutrition Group, Wageningen University, PO Box 338, 6700 AH Wageningen, the Netherlands. Electronic address: - - 2014
The ability to monitor dairy cow feeding behavior and activity could improve dairy herd management. A 3-dimensional accelerometer (SensOor; Agis Automatisering BV, Harmelen, the Netherlands) has been developed that can be attached to ear identification tags. Based on the principle that behavior can be identified by ear movements, a proprietary ...
Kuntner Claudia C Biomedical Systems, Health & Environment Department, AIT Austrian Institute of Technology GmbH, Seibersdorf, Austria. Electronic address: - - 2014
Preclinical positron emission tomography (PET) has evolved in the last few years from pure visualization of radiotracer uptake and distribution towards quantification of the physiological parameters. For reliable and reproducible quantification the kinetic modeling methods used to obtain relevant parameters of radiotracer tissue interaction are important. Here we present different ...
Wardak Mirwais M Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, 10833 Le Conte Ave, Los Angeles, CA, 90095-6948, - - 2014
In this study, kinetic parameters of the cellular proliferation tracer (18)F-3'-deoxy-3'-fluoro-L-thymidine (FLT) and the amino acid probe 3,4-dihydroxy-6-(18)F-fluoro-L-phenylalanine (FDOPA) were measured before and early after the start of therapy, and were used to predict the overall survival (OS) of patients with recurrent malignant glioma using multiple linear regression (MLR) analysis. ...
Wang Lei L University of Wollongong, - - 2014
In image recognition with the bag-of-features model, a small-sized visual codebook is usually preferred to obtain a low-dimensional histogram representation and high computational efficiency. Such a visual codebook has to be discriminative enough to achieve excellent recognition performance. To create a compact and discriminative codebook, in this paper we propose ...
Niaf Emilie - - 2014
Building an accurate training database is challenging in supervised classification. For instance, in medical imaging, radiologists often delineate malignant and benign tissues without access to the histological ground truth, leading to uncertain data sets. This paper addresses the pattern classification problem arising when available target data include some uncertainty information. ...
Virués-Ortega Javier - - 2014
Abstract Individuals with intellectual or developmental disabilities are able to reliably express their likes and dislikes through direct preference assessment. Preferred items tend to function as rewards and can therefore be used to facilitate the acquisition of new skills and promote task engagement. A number of preference assessment methods are ...
Lee Hanshin - - 2014
The shape of a focus-modulated point spread function (PSF) is used as a quick visual assessment tool of aberration modes in the PSF. Further analysis in terms of shape moments can permit quantifying the modal coefficients with an accuracy comparable to that of typical wavefront sensors. In this Letter, the ...
Xianming Liu - - 2014
In this paper, we propose a novel image interpolation algorithm via graph-based Bayesian label propagation. The basic idea is to first create a graph with known and unknown pixels as vertices and with edge weights encoding the similarity between vertices, then the problem of interpolation converts to how to effectively ...
Le Montagner Yoann - - 2014
The behavior and performance of denoising algorithms are governed by one or several parameters, whose optimal settings depend on the content of the processed image and the characteristics of the noise, and are generally designed to minimize the mean squared error (MSE) between the denoised image returned by the algorithm ...
En-Hui Yang - - 2014
The distributions of discrete cosine transform (DCT) coefficients of images are revisited on a per image base. To better handle, the heavy tail phenomenon commonly seen in the DCT coefficients, a new model dubbed a transparent composite model (TCM) is proposed and justified for both modeling accuracy and an additional ...
Zhong Jian J School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, - - 2014
Air quality models include representations of pollutant emissions, which necessarily entail spatial averaging to reflect the model grid size; such averaging may result in significant uncertainties and/or systematic biases in the model output. This study investigates such uncertainties, considering ozone concentrations in idealised street canyons within the urban canopy. A ...
Strobbe Gregor G Ghent University - iMinds, Department of Electronics and Information Systems, MEDISIP, De Pintelaan 185, Building BB floor 5, 9000, Ghent, Belgium. Electronic address: - - 2014
Several EEG source reconstruction techniques have been proposed to identify the generating neuronal sources of electrical activity measured on the scalp. The solution of these techniques depends directly on the accuracy of the forward model that is inverted. Recently, a parametric empirical Bayesian (PEB) framework for distributed source reconstruction in ...
Kapron Ashley L AL Department of Orthopaedics, University of Utah, Salt Lake City, - - 2014
Accurate measurements of in-vivo hip kinematics may elucidate the mechanisms responsible for impaired function and chondrolabral damage in hips with femoroacetabular impingement (FAI). The objectives of this study were to quantify the accuracy and demonstrate the feasibility of using dual fluoroscopy to measure in-vivo hip kinematics during clinical exams used ...
Liagkouridis Ioannis I IVL Swedish Environmental Research Institute, P.O. Box 21060, SE 100 31 Stockholm, Sweden; ITM Department of Applied Environmental Science, Stockholm University, SE 106 91 Stockholm, Sweden. Electronic address: - - 2014
This review explores the existing understanding and the available approaches to estimating the emissions and fate of semi-volatile organic compounds (SVOCs) and in particular focuses on the brominated flame retardants (BFRs). Volatilisation, an important emission mechanism for the more volatile compounds can be well described using current emission models. More ...
Zhang Xin - - 2014
Copy Number Variations (CNVs) are usually inferred from Single Nucleotide Polymorphism (SNP) arrays by use of some software packages based on given algorithms. However, there is no clear understanding of the performance of these software packages; it is therefore difficult to select one or several software packages for CNV detection ...
Marshall Julian D - - 2014
Existing environmental policies aim to reduce emissions but lack standards for addressing environmental justice. Environmental justice research documents disparities in exposure to air pollution; however, little guidance currently exists on how to make improvements or on how specific emission-reduction scenarios would improve or deteriorate environmental justice conditions. Here we quantify ...
Cesa Mattia M Life Sciences Department, University of Trieste, Via L. Giorgieri, 10, 34127, Trieste, Italy, - - 2014
An equation to estimate Hg concentrations of <4 μg/L in groundwaters of a polluted area in NE Italy was set out by using transplants of the aquatic moss Rhynchostegium riparioides as trace element bioaccumulators. The equation is derived from a previous mathematical model which was implemented under laboratory conditions. The work ...
Sabariego Manuel P MP Departamento de Fisica Atomica, Molecular y Nuclear, Facultad de Ciencias, Universidad de Granada, Granada, - - 2014
To investigate the peak shown by the American Association of Physicists in Medicine (AAPM) Task Group 43 1D anisotropy function at short distances from the source. The 1D anisotropy function of an ideal nonencapsulated photon linear source is calculated. A simple analytical model developed to evaluate the dose because of ...
Stovern Michael - - 2014
Abstract Mining operations are potential sources of airborne particulate metal and metalloid contaminants through both direct smelter emissions and wind erosion of mine tailings. The warmer, drier conditions predicted for the Southwestern US by climate models may make contaminated atmospheric dust and aerosols increasingly important, due to potential deleterious effects ...
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