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Wang Xiao-Feng XF Department of Quantitative Health Sciences / Biostatistics Section, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, - - 2015
This paper is motivated by a wide range of background correction problems in gene array data analysis, where the raw gene expression intensities are measured with error. Estimating a conditional density function from the contaminated expression data is a key aspect of statistical inference and visualization in these studies. We ...
Vexler Albert A Department of Biostatistics, New York State University at Buffalo, 715 Kimball Tower, 3435 Main Street, Buffalo, NY, 14214, USA, - - 2015
The aim of this chapter is to review and examine different methods in order to display correct and efficient statistical techniques based on complete/incomplete data subject to different sorts of measurement error (ME) problems. Instrument inaccuracies, biological variations, and/or errors in questionnaire-based self-report data can lead to significant MEs in ...
Liu Jie J Department of Computer Sciences, University of - - 2014
It has been shown that graphical models can be used to leverage the dependence in large-scale multiple testing problems with significantly improved performance (Sun & Cai, 2009; Liu et al., 2012). These graphical models are fully parametric and require that we know the parameterization of f 1 - the density ...
Ghanbarnejad Fakhteh F Max Planck Institute for the Physics of Complex Systems, Dresden, Germany - - 2014
It is well accepted that adoption of innovations are described by S-curves (slow start, accelerating period and slow end). In this paper, we analyse how much information on the dynamics of innovation spreading can be obtained from a quantitative description of S-curves. We focus on the adoption of linguistic innovations ...
Chi Eric C EC Department of Electrical and Computer Engineering, Rice University, Texas, - - 2014
Estimation of a covariance matrix or its inverse plays a central role in many statistical methods. For these methods to work reliably, estimated matrices must not only be invertible but also well-conditioned. The current paper introduces a novel prior to ensure a well-conditioned maximum a posteriori (MAP) covariance estimate. The ...
Solberg Svein S Norwegian Forest and Landscape Institute, P.O. Box 115, 1431 Ås, - - 2014
There is a need for new satellite remote sensing methods for monitoring tropical forest carbon stocks. Advanced RADAR instruments on board satellites can contribute with novel methods. RADARs can see through clouds, and furthermore, by applying stereo RADAR imaging we can measure forest height and its changes. Such height changes ...
Jin Zhongming - - 2014
Recently, the hashing techniques have been widely applied to approximate the nearest neighbor search problem in many real applications. The basic idea of these approaches is to generate binary codes for data points which can preserve the similarity between any two of them. Given a query, instead of performing a ...
Washizawa Yoshikazu - - 2014
In pattern classification problems, pattern variations are often modeled as a linear manifold or a low-dimensional subspace. Conventional methods use such models and define a measure of similarity or dissimilarity. However, these similarity measures are deterministic and do not take into account the distribution of linear manifolds or low-dimensional subspaces. ...
Cuesta Izquierdo Marcelino M Universidad de - - 2014
The problem of missing values at the item level is common in studies using educational and psychological tests. The aim of the present work is to explore how the estimation of reliability is affected by missing values. Using real data, we simulated missing values in accordance with a "missing at ...
Xi Wenjing W Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, - - 2014
There are many methods of measuring the breast and their clinical applications are well described in the literature. However, there has been no attempt to compare these various methods to allow the user to have a broad overview of the subject. The authors have attempted to summarise all the available ...
Berendsen Brenda A J BA Human Movement Science, NUTRIM, School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre, PO Box 616, 6200 MD Maastricht, The - - 2014
A valid non-wear algorithm for activity monitors is crucial to avoid the misclassification of sedentary time as non-wear time, and vice versa. Characteristics of the algorithm, such as time windows, should be well defined and tested. Furthermore, using tri-axial data might influence the algorithm's performance. This study assessed the optimal ...
Ellis Katherine K Department of Electrical and Computer Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0407, - - 2014
Wrist accelerometers are being used in population level surveillance of physical activity (PA) but more research is needed to evaluate their validity for correctly classifying types of PA behavior and predicting energy expenditure (EE). In this study we compare accelerometers worn on the wrist and hip, and the added value ...
Wallén Martin Benka MB Division of Physiotherapy, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 141 83 Huddinge, - - 2014
This study compared common free-living physical activity (PA) outcomes, assessed with the Actigraph GT3X+ accelerometer and processed with two different filter settings, in a sample of elderly individuals with Parkinson´s disease (PD). Sixty-six individuals (73.1  ±  5.8 years) with mild to moderate idiopathic PD carried an accelerometer for 7 d. Data were processed with ...
Beck Robin M D RM School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia - - 2014
Analyses of a comprehensive morphological character matrix of mammals using 'relaxed' clock models (which simultaneously estimate topology, divergence dates and evolutionary rates), either alone or in combination with an 8.5 kb nuclear sequence dataset, retrieve implausibly ancient, Late Jurassic-Early Cretaceous estimates for the initial diversification of Placentalia (crown-group Eutheria). These ...
Pleasants A B AB 1Mathematical Biology Department,AgResearch,Hamilton,New - - 2014
The principles embodied by the Developmental Origins of Health and Disease (DOHaD) view of 'life history' trajectory are increasingly underpinned by biological data arising from molecular-based epigenomic and transcriptomic studies. Although a number of 'omic' platforms are now routinely and widely used in biology and medicine, data generation is frequently ...
Cutts Catherine S CS Cambridge Computational Biology Institute Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA, United Kingdom - - 2014
Correlations in neuronal spike times are thought to be key to processing in many neural systems. Many measures have been proposed to summarize these correlations and of these the correlation index is widely used and is the standard in studies of spontaneous retinal activity. We show that this measure has ...
Azevedo Sílvia S REQUIMTE/DGAOT, Faculty of Sciences, University of Porto, Porto, - - 2014
The respiration rate of mushrooms is an important indicator of postharvest senescence. Storage temperature plays a major role in their rate of respiration and, therefore, in their postharvest life. In this context, reliable predictions of respiration rates are critical for the development of modified atmosphere packaging that ultimately will maximise ...
Wu Jianrong J Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, TN 38105, - - 2014
In this paper, an exact variance of the one-sample log-rank test statistic is derived under the alternative hypothesis, and a sample size formula is proposed based on the derived exact variance. Simulation results showed that the proposed sample size formula provides adequate power to design a study to compare the ...
Ochs Christopher C Computer Science Department, New Jersey Institute of Technology, Newark, New Jersey, - - 2014
Standards terminologies may be large and complex, making their quality assurance challenging. Some terminology quality assurance (TQA) methodologies are based on abstraction networks (AbNs), compact terminology summaries. We have tested AbNs and the performance of related TQA methodologies on small terminology hierarchies. However, some standards terminologies, for example, SNOMED, are ...
Agatonovic-Kustrin Snezana S School of Pharmacy and Applied Science, La Trobe Institute of Molecular Sciences, La Trobe University, Bendigo, Australia. - - 2014
Human activities have introduced tens of thousands of chemicals into water systems around the world which has significantly impacted water quality and aquatic ecosystems. The aim of this study was to develop an in silico QSAR model, capable of predicting the aquatic toxicity of pesticides in terms of a lethal ...
Martre Pierre P INRA, UMR1095 Genetics, Diversity and Ecophysiology of Cereals (GDEC), 5 chemin de Beaulieu, F-63 100, Clermont-Ferrand, France; Blaise Pascal University, UMR1095 GDEC, F-63 170, Aubière, - - 2014
Crop models of crop growth are increasingly used to quantify the impact of global changes due to climate or crop management. Therefore, accuracy of simulation results is a major concern. Studies with ensembles of crop models can give valuable information about model accuracy and uncertainty, but such studies are difficult ...
Gemayel Nader N JPMorgan Chase, Columbus, OH, - - 2014
Ranked set sampling (RSS) is a data collection technique that combines measurement with judgment ranking for statistical inference. This paper lays out a formal and natural Bayesian framework for RSS that is analogous to its frequentist justification, and that does not require the assumption of perfect ranking or use of ...
ElMoaqet Hisham H Mechanical Engineering Department, University of Michigan, Ann Arbor, MI, 48109, USA, - - 2014
Episodic postoperative desaturation occurs predominantly from respiratory depression or airway obstruction. Monitor display of desaturation is typically delayed by over 30 s after these dynamic inciting events, due to perfusion delays, signal capture and averaging. Prediction of imminent critical desaturation could aid development of dynamic high-fidelity response systems that reduce or ...
Andersen Jeppe Ragnar JR Nordic Bioscience A/S, Herlev, - - 2014
The aim of this project was to perform an empirical evaluation of the impact of on-site Source Data Verification (SDV) on the data quality in a clinical trial database to guide an informed decision on selection of monitoring approach. We used data from three randomised phase III trials monitored with ...
Hedayat A S AS Department of Mathematics, Statistics, and Computer Science, University of Illinois at Chicago, Chicago, Illinois 60607, - - 2014
In clinical trials, minimum clinically important difference (MCID) has attracted increasing interest as an important supportive clinical and statistical inference tool. Many estimation methods have been developed based on various intuitions, while little theoretical justification has been established. This article proposes a new estimation framework of the MCID using both ...
Park Byoung-Keon BK a Biosciences Group , University of Michigan Transportation Research Institute , Ann Arbor , MI , - - 2014
We present a new method for rapidly measuring child body shapes from noisy, incomplete data captured from low-cost depth cameras. This method fits the data using a statistical body shape model (SBSM) to find a complete avatar in the realistic body shape space. The method also predicts a set of ...
Young Alexander I AI University of Oxford; - - 2014
Genetic association studies have explained only a small proportion of the estimated heritability of complex traits, leaving the remaining heritability 'missing'. Genetic interactions have been proposed as an explanation for this, because they lead to overestimates of the heritability and are hard to detect. Whether this explanation is true depends ...
Leffondre Karen K University of Bordeaux, ISPED, Centre INSERM U897-Epidemiology-Biostatistics, Bordeaux, - - 2014
The most commonly used methods to investigate risk factors associated with renal function trajectory over time include linear regression on individual glomerular filtration rate (GFR) slopes, linear mixed models and generalized estimating equations (GEEs). The objective of this study was to explain the principles of these three methods and to ...
Ragab Marwa A A MA Faculty of Pharmacy, Department of Pharmaceutical Analytical Chemistry, University of Alexandria, El-Messalah, Alexandria, 21521, Egypt, - - 2014
A spectrofluorimetric method was used for the estimation of closely related fluorescent reaction products, Fluoxetine and Olanzapine, in their mixture after derivatization of both drugs using 4-chloro-7- nitrobenzo - 2 -oxa-1,3 - diazole (NBD-Cl) in borate buffered medium (pH 9.5) to form highly fluorescent products. The method based on the ...
Lin Hung-Mo HM a Hung-Mo Lin, Department of Health Evidence and Policy , Mount Sinai School of Mledicine , One Gustave L. Levy Place, Box 1077, New York , NY 10029 , U.S.A - - 2014
ABSTRACT Some studies are designed to assess the agreement between different raters and/or different instruments in the medical sciences and pharmaceutical research. In practice, the same sample will be used to compare the agreement of two or more assessment methods for simplicity and to take advantage of the positive correlation ...
Lehman Paul A PA QPS, LLC, Delaware Technology Park, Newark, Delaware, - - 2014
Historically, percutaneous absorption permeation parameters have been derived from in vitro infinite dose studies, yet there is uncertainty in their accuracy if the applied vehicle saturates or damages the stratum corneum, or when the permeation parameters are inappropriately derived from cumulative absorption data. An approach is provided for determining penetration ...
Willemsen A Marcel AM Bioinformatics Laboratory, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Academical Medical Centre, Amsterdam, The - - 2014
Understanding cellular adaptation to environmental changes is one of the major challenges in systems biology. To understand how cellular systems react towards perturbations of their steady state, the metabolic dynamics have to be described. Dynamic properties can be studied with kinetic models but development of such models is hampered by ...
Ping Qingyun - - 2014
Microbial desalination cells (MDCs) are an emerging concept for simultaneous wastewater treatment and water desalination. This work presents a mathematical model to simulate dynamic behavior of MDCs for the first time through evaluating multiple factors such as organic supply, salt loading and current generation. Ordinary differential equations were applied to ...
Letchford Robert R School of Healthcare Sciences, Cardiff University, Second Floor, Cardigan House, Heath Park Campus, Cardiff, CF14 4XN, UK, - - 2014
Single leg hop for distance is used to inform rehabilitation and return to sport following anterior cruciate ligament reconstruction. However, impairment of landing mechanics may persist after the recommended performance parameter (hop distance) has been met; therefore, alternative methods are required. This study follows the COSMIN guideline to investigate the ...
Liu Tianfei - - 2014
BackgroundGrowth and carcass traits are very important traits for broiler chickens. However, carcass traits can only be measured postmortem. Genomic selection may be a powerful tool for such traits because of its accurate prediction of breeding values of animals without own phenotypic information. This study investigated the efficiency of genomic ...
Kehimkar Benjamin B Department of Chemistry, University of Washington, Box 351700, Seattle, WA, 98195, - - 2014
Recent efforts in predicting rocket propulsion (RP-1) fuel performance through modeling put greater emphasis on obtaining detailed and accurate fuel properties, as well as elucidating the relationships between fuel compositions and their properties. Herein, we study multidimensional chromatographic data obtained by comprehensive two-dimensional gas chromatography combined with time-of-flight mass spectrometry ...
Alvarsson Jonathan - - 2014
QSAR modeling using molecular signatures and support vector machines with a radial basis function is increasingly used for virtual screening in the drug discovery field. This method has three free parameters: C, γ and signature height. C is a penalty parameter which limits over-fitting, γ controls the width of the ...
Jawień Wojciech W Faculty of Pharmacy, Jagiellonian University in Kraków, ul. Medyczna 9, 30-688, Kraków, Poland, - - 2014
An effective method of construction of a linear estimator of AUC in the finite interval, optimal in the minimax sense, is developed and demonstrated for five PK models. The models may be given as an explicit C(t) relationship or defined by differential equations. For high variability and rich sampling the ...
Toseland Andrew - - 2014
Metatranscriptome sequence data can contain highly redundant sequences from diverse populations of microbes and so data reduction techniques are often applied before taxonomic and functional annotation. For metagenomic data, it has been observed that the variable coverage and presence of closely related organisms can lead to fragmented assemblies containing chimeric ...
Klumpp John J Environmental and Radiological Health Sciences, Colorado State University, 1618 Campus Delivery, Fort Collins, CO 80523, USA - - 2014
A 'moving-target' method for characterising background in a counting measurement in which the instantaneous background count rate is a function of time, rather than being fixed, is proposed. This model treats the average Poisson mean in observation period P as coming from a gamma distribution with parameters αP and βP. ...
Brisman Jonas J Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, - - 2014
A spirometric reference equation consists of a mathematical model with constants and coefficients optimized to fit a specific data set from healthy individuals. Commonly applied models are selected on statistical rather than physiological considerations. A predetermined model with constants and coefficients optimized to various populations would enable interpretable and interesting ...
Dennis Emily B EB School of Mathematics, Statistics and Actuarial Science, University of Kent, Canterbury, Kent CT2 7NF, - - 2014
The N-mixture model is widely used to estimate the abundance of a population in the presence of unknown detection probability from only a set of counts subject to spatial and temporal replication (Royle, 2004, Biometrics 60, 105-115). We explain and exploit the equivalence of N-mixture and multivariate Poisson and negative-binomial ...
Grabowski Tomasz T Polpharma Biologics, Trzy Lipy 3, 80-172, Gdańsk, Poland, - - 2014
This study attempted to determine the area under the curve ([Formula: see text]), which corresponds to the sum of all elimination processes correlated with the total clearance value. The study attempted to determine the [Formula: see text] based on the coordinates known from classic non-compartmental pharmacokinetics for a single administration ...
Bilge Ayse Humeyra AH Department of Industrial Engineering, Faculty of Engineering and Natural Sciences, Kadir Has University, Istanbul, Turkey, - - 2014
The susceptible-infected-removed (SIR) and the susceptible-exposed-infected-removed (SEIR) epidemic models with constant parameters are adequate for describing the time evolution of seasonal diseases for which available data usually consist of fatality reports. The problems associated with the determination of system parameters starts with the inference of the number of removed individuals ...
Xu Xinghua X From the Department of Neurosurgery, Chinese PLA General Hospital, Beijing, - - 2014
The Tada (ABC/2) formula has been used widely for volume assessment of intracerebral hematoma. However, the formula is crude for irregularly shaped hematoma. We aimed to compare the accuracy of the ABC/2 formula with open source software Slicer. Computed tomographic images of 294 patients with spontaneous intracerebral hematoma were collected. ...
Tang Nick - - 2014
We present a novel two-pass framework for counting the number of people in an environment where multiple cameras provide different views of the subjects. By exploiting the complementary information captured by the cameras, we can transfer knowledge between the cameras to address the difficulties of people counting and improve the ...
Faller James E JE JILA, University of Colorado and National Institute of Standards and Technology, Boulder, CO 80309, USA Institute for Gravitational Research, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK - - 2014
Determinations of the Newtonian constant of gravitation (big G) fit into the oftentimes-unappreciated area of physics called precision measurement-an area which includes precision measurements, null experiments and determinations of the fundamental constants. The determination of big G-a measurement which on the surface appears deceptively simple-continues to be one of Nature's ...
Wood Barry M BM National Research Council of Canada, 1200 Montreal Road, Ottawa, Ontario, ON K1A 0R6 Canada - - 2014
The primary objective of the CODATA Task Group on Fundamental Constants is 'to periodically provide the scientific and technological communities with a self-consistent set of internationally recommended values of the basic constants and conversion factors of physics and chemistry based on all of the relevant data available at a given ...
Santa-Ana-Tellez Yared Y WHO Collaborating Centre for Pharmaceutical Policy & Regulation, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht, the - - 2014
During 2010, Mexico and Brazil implemented policies to enforce existing laws of restricting over-the-counter sales of antibiotics. We determined if the enforcement led to more appropriate use by measuring changes in seasonal variation of penicillin use. We used retail quarterly sales data in defined-daily-dose per 1000 inhabitants-day (DDD/TID) from IMS ...
Steven Ernest C C 2nd Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden, - - 2014
D-optimal designs for discrete-type responses have been derived using generalized linear mixed models, simulation based methods and analytical approximations for computing the fisher information matrix (FIM) of non-linear mixed effect models with homogeneous probabilities over time. In this work, D-optimal designs using an analytical approximation of the FIM for a ...
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