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Results 51 - 100 of 1997
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Iknayan Kelly J - - 2013
Estimates of species richness and diversity are central to community and macroecology and are frequently used in conservation planning. Commonly used diversity metrics account for undetected species primarily by controlling for sampling effort. Yet the probability of detecting an individual can vary among species, observers, survey methods, and sites. We ...
Havelka Miroslav M Czech Metrology Institute, Inspectorate for Ionizing Radiation, Radiová 1, 102 00 Prague, Czech Republic. Electronic address: - - 2013
The activity of the radionuclide (64)Cu was determined by the efficiency extrapolation method applied to 4π(PC)-γ coincidence counting. The standardisation was performed by software coincidence counting-a digital method for primary activity measurement that simplifies the setting of optimal coincidence parameters. The γ-ray-energy window, characterised by identical gamma detection efficiency related ...
Lee Chang-Hyun - - 2013
The sylvian arachnoid cyst (AC) is a common benign disease; however, it sometimes leads to subdural or intracystic hemorrhage without major trauma. The reason of easy bleeding of the AC is not fully understood. The purpose of this study was to investigate the bleeding mechanism of the sylvian AC in ...
Hardy J C - - 2013
Because of angular-momentum conservation, superallowed β decay between 0(+) analog states involves only the vector part of the weak interaction, so its measured ft value can be used to determine the vector coupling constant, GV. If many such transitions are measured, then the constancy of GV can be established and ...
Battisti Sabrina - - 2013
In May 2005, beta-hexachlorocyclohexane (β-HCH) was found in a sample of bovine bulk milk from a farm in the Sacco River valley (Latium region, central Italy). The primary source of contamination was suspected to be industrial discharge into the environment with the Sacco River as the main mean of dispersion. ...
Wentao Fan - - 2013
A large class of problems can be formulated in terms of the clustering process. Mixture models are an increasingly important tool in statistical pattern recognition and for analyzing and clustering complex data. Two challenging aspects that should be addressed when considering mixture models are how to choose between a set ...
Kalantari Mojgan M Department of Radiology, Mahdiyeh Hospital, Shahid Beheshti University of Medical Sciences, Tehran, - - 2013
Abdominal circumference (AC), biparietal diameters (BPD) and femoral length (FL) are now the main parameters used to obtain estimated fetal weight (EFW). Although the role of soft tissue parameters in determining fetal weight was proved but clinical attention to mid-thigh soft tissue thickness (STT) is limited. To find the impression ...
Zhou Mingyuan - - 2013
The seemingly disjoint problems of count and mixture modeling are united under the negative binomial (NB) process. A gamma process is employed to model the rate measure of a Poisson process, whose normalization provides a random probability measure for mixture modeling and whose marginalization leads to a NB process for ...
He Wenqi - - 2013
We comment on the recent Letter, by Liu et al. [Opt. Lett.38, 1651 (2013)] in which a method to improve the security strength of the asymmetric cryptosystem (ACS) by Qin and Peng [Opt. Lett.35, 118 (2010)] was proposed. However, in accordance with Liu's methodology, we could easily find other more efficient ...
Yu Xiaoyi - - 2013
Long-term storage of articular cartilage (AC) has excited great interest due to the practical surgical significance of this tissue. The liquidus-tracking (LT) method developed by Pegg et al. [Cryobiology, 52 (2006) 360-368] for vitreous preservation of AC achieved reasonable survival of post-warming chondrocytes in situ, but the design of the ...
Sathyamoorthy Sandeep - - 2013
Accurate prediction of pharmaceutical concentrations in wastewater effluents requires that the specific biochemical processes responsible for pharmaceutical biodegradation be elucidated and integrated within any modeling framework. The fate of three selected beta blockers - atenolol, metoprolol, and sotalol - was examined during nitrification using batch experiments to develop and evaluate ...
Carvalho Susana - - 2013
The present study analyses the composition, structure and trophic function of epibenthic assemblages in two artificial reefs (ARs) 16 years after deployment and in nearby natural reefs (NRs), aiming at providing insights on the complementarity between both habitats. Current findings suggest that after 16 years the ARs (concrete blocks), located ...
Cisler Josh M - - 2013
Many cognitive and clinical neuroscience research studies seek to determine how contextual factors modulate cognitive processes. In fMRI, hypotheses about how context modulates distributed patterns of information processing are often tested by comparing functional connectivity between neural regions A and B as a function of task condition X and Y, ...
Salari Nader - - 2013
The classification of Acute Coronary Syndrome (ACS), using artificial intelligence (AI), has recently drawn the attention of the medical researchers. Using this approach, patients with myocardial infarction can be differentiated from those with unstable angina. The present study aims to develop an integrated model, based on the feature selection and ...
Silva M M - - 2014
This paper addresses the local identifiability and sensitivity properties of two classes of Wiener models for the neuromuscular blockade and depth of hypnosis, when drug dose profiles like the ones commonly administered in the clinical practice are used as model inputs. The local parameter identifiability was assessed based on the ...
Hansson Mari - - 2013
High-throughput screening (HTS) is widely used in the pharmaceutical industry to identify novel chemical starting points for drug discovery projects. The current study focuses on the relationship between molecular hit rate in recent in-house HTS and four common molecular descriptors: lipophilicity (ClogP), size (heavy atom count, HEV), fraction of sp(3)-hybridized ...
El Karoui Noureddine N Department of Statistics, University of California, Berkeley, CA 94720, USA. - - 2013
We study regression M-estimates in the setting where p, the number of covariates, and n, the number of observations, are both large, but p ≤ n. We find an exact stochastic representation for the distribution of β = argmin(β∈ℝ(p)) Σ(i=1)(n) ρ(Y(i) - X(i')β) at fixed p and n under various ...
Comas J - - 2013
Field trials may be required to assess risks of genetically modified crops (GMCs) for nontarget arthropods. One critical point of these trials is their capacity to detect differences between the density of one taxon in the GMC and that in the comparator. The detection capacity of a trial depends on ...
Kuss Oliver - - 2013
There are still challenges when meta-analyzing data from studies on diagnostic accuracy. This is mainly due to the bivariate nature of the response where information on sensitivity and specificity must be summarized while accounting for their correlation within a single trial. In this paper, we propose a new statistical model ...
Tan Vincent Y F - - 2013
This paper addresses the estimation of the latent dimensionality in nonnegative matrix factorization (NMF) with the $(\beta)$--divergence. The $(\beta)$-divergence is a family of cost functions that includes the squared euclidean distance, Kullback-Leibler (KL) and Itakura-Saito (IS) divergences as special cases. Learning the model order is important as it is necessary ...
Legendre Pierre - - 2013
Beta diversity can be measured in different ways. Among these, the total variance of the community data table Y can be used as an estimate of beta diversity. We show how the total variance of Y can be calculated either directly or through a dissimilarity matrix obtained using any dissimilarity ...
Yang Lingling - - 2013
Studies have shown that statistically there are differences in theta, alpha and beta band powers when people look at blue and red colors. In this paper, a game has been developed to test whether these statistical differences are good enough for online Brain Computer Interface (BCI) application. We implemented a ...
Horoi M - - 2013
Neutrinoless double beta decay, if observed, could distinguish whether the neutrino is a Dirac or a Majorana particle, and it could be used to determine the absolute scale of the neutrino masses. ^{136}Xe is one of the most promising candidates for observing this rare event. However, until recently there were ...
El Kerdawy Ahmed - - 2013
We have used a set of four local properties based on semiempirical molecular orbital calculations (the electron density (ρ), hydrogen bond donor field (HDF), hydrogen bond acceptor field (HAF) and molecular lipophilicity potential (MLP)) for 3D-QSAR studies to overcome the limitations of the current force-field based molecular interaction fields (MIFs). ...
Rosano Camillo C IRCCS SM-IST, U.O.S. Biopolimeri e Proteomica , Largo R. Benzi 10, 16132 Genova, - - 2013
Docking methods are powerful tools for in silico screening and drug lead generation and optimization. Here, we describe the synthesis of new inhibitors of ABCB1 whose design was based on construction and preliminary confirmation of a model for this membrane transporter of the ATP-binding cassette family. We chose the strategy ...
Xu Xu Steven - - 2013
Beta regression models have been recommended for continuous bounded outcome scores that are often collected in clinical studies. Implementing beta regression in NONMEM presents difficulties since it does not provide gamma functions required by the beta distribution density function. The objective of the study was to implement mixed-effects beta regression ...
Srinivas Nuggehally R - - 2013
Ciclesonide, a novel glucocorticosteroid, through a rapid metabolism to desisobutyryl-ciclesonide (des-ciclesonide), provides an effective treatment option for asthma episodes by the inhaled route of administration. The availability of pharmacokinetic parameters (clearance [CL/F]; volume of distribution [Vd/F]; elimination half-life [T1/2]; and elimination rate constant [Kel]) in mice, rats, rabbits, and dogs ...
Tulupyev Alexander - - 2013
Our aim is to model the frequency of certain behavioral acts, especially those that are likely to transmit communicable diseases between persons. We develop a generalized linear model on the basis of the beta prime distribution to model the responses to a survey question of the form, 'When was the ...
Domenech de Cellès Matthieu - - 2013
BACKGROUND: Extended-spectrum beta-lactamase--producing Enterobacteriaceae (ESBL-E) are a growing concern in hospitals and the community. How to control the nosocomial ESBL-E transmission is a matter of debate. Contact isolation of patients has been recommended but evidence supporting it in non-outbreak settings has been inconclusive. METHODS: We used stochastic transmission models to ...
Boot Maikel - - 2013
BACKGROUND: Genes encoding Extended Spectrum Beta Lactamases are usually located on transferable plasmids. Each plasmid contains its own replication mechanism. Carattoli et al. developed an extended PCR-based replicon typing method to characterize and identify the replicons of the major plasmid incompatibility groups in Enterobacteriaceae. Based on this method, we designed ...
Moorthy N S Hari Narayana - - 2013
Abstract In the present computational analysis, pharmacophore-based active conformer selection method was used to derive active conformers for the physicochemical descriptors calculation. The significant regression models were validated using different validation methods, which provided significant Q(2) values. The distance-based approaches were also used to analyze the discriminant property of the ...
Rocha J Leonel - - 2013
In this work a new probabilistic and dynamical approach to an extension of the Gompertz law is proposed. A generalized family of probability density functions, designated by Beta • (p,q), which is proportional to the right hand side of the Tsoularis-Wallace model, is studied. In particular, for p=2, the investigation ...
Vojniković Bozo - - 2013
The authors discussed about the problem of special form in astigmatism classification. This special type of astigmatism is the form of obliquely crossed astigmatism. In which the meridians, major and minor, are not right angles. In this astigmatism is not possible to prescribing for cylindrical (toric) spectacle lens. Authors describe ...
Liu Chuan-Fen - - 2013
OBJECTIVE: To illustrate how the analysis of bimodal U-shaped distributed utilization can be modeled with beta-binomial regression, which is rarely used in health services research. DATA SOURCES/STUDY SETTING: Veterans Affairs (VA) administrative data and Medicare claims in 2001-2004 for 11,123 Medicare-eligible VA primary care users in 2000. STUDY DESIGN: We ...
Huillet Thierry E - - 2013
We study a class of coalescents derived from a sampling procedure out of [Formula: see text] i.i.d. Pareto[Formula: see text] random variables, normalized by their sum, including [Formula: see text] -size-biasing on total length effects ([Formula: see text]). Depending on the range of [Formula: see text] we derive the large ...
Yu Xiaoyi X Institute of Refrigeration and Cryogenics, Zhejiang University , Hangzhou, China - - 2013
Cryopreservation of articular cartilage (AC) has excited great interest due to the practical surgical importance of this tissue. Characterization of permeation kinetics of cryoprotective agents (CPA) in AC is important for designing optimal CPA addition/removal protocols to achieve successful cryopreservation. Permeation is predominantly a mass diffusion process. Since the diffusivity ...
Steinrücken Matthias M Department of Statistics, University of California, 367 Evans Hall MC 3860, Berkeley, CA 94720-3860, USA. - - 2013
We apply recently developed inference methods based on general coalescent processes to DNA sequence data obtained from various marine species. Several of these species are believed to exhibit so-called shallow gene genealogies, potentially due to extreme reproductive behaviour, e.g. via Hedgecock's "reproduction sweepstakes". Besides the data analysis, in particular the inference ...
Schmidt Philip J - - 2013
Dose-response models are the essential link between exposure assessment and computed risk values in quantitative microbial risk assessment, yet the uncertainty that is inherent to computed risks because the dose-response model parameters are estimated using limited epidemiological data is rarely quantified. Second-order risk characterization approaches incorporating uncertainty in dose-response model ...
Bordonali L - - 2013
We present a systematic experimental comparison of the superparamagnetic relaxation time constants obtained by means of dynamic magnetic measurements and (1)H-NMR relaxometry, on ferrite-based nanosystems with different composition, various core sizes and dispersed in different solvents. The application of a heuristic model for the relaxivity allowed a comparison between the ...
Jiang Guoqian - - 2013
The beta phase of the 11th revision of International Classification of Diseases (ICD-11) intends to accept public input through a distributed model of authoring. One of the core use cases is to create textual definitions for the ICD categories. The objective of the present study is to design, develop, and ...
Chen Rongda - - 2013
Recovery rate is essential to the estimation of the portfolio's loss and economic capital. Neglecting the randomness of the distribution of recovery rate may underestimate the risk. The study introduces two kinds of models of distribution, Beta distribution estimation and kernel density distribution estimation, to simulate the distribution of recovery ...
Schmid Matthias M Department of Medical Informatics, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany. - - 2013
Regression analysis with a bounded outcome is a common problem in applied statistics. Typical examples include regression models for percentage outcomes and the analysis of ratings that are measured on a bounded scale. In this paper, we consider beta regression, which is a generalization of logit models to situations where ...
Birkner Thomas T Department of Biostatistics, University of Alabama at Birmingham, Birmingham, - - 2013
We present a frequentist Bernoulli-Beta hierarchical model to relax the constant prevalence assumption underlying the traditional prevalence estimation approach based on pooled data. This assumption is called into question when sampling from a large geographic area. Pool screening is a method that combines individual items into pools. Each pool will ...
Ng Bernard B Parietal team, Neurospin, INRIA Saclay, France. - - 2013
There is a recent trend towards integrating resting state functional magnetic resonance imaging (RS-fMRI) and diffusion MRI (dMRI) for brain connectivity estimation, as motivated by how estimates from these modalities are presumably two views reflecting the same underlying brain circuitry. In this paper, we show on a cohort of 60 ...
Elsayed Samir A Mohamed SA Computer Science Department, University of Connecticut, Storrs, CT 06269, Helwan University, Cairo, Egypt - - 2013
Traditional Associative Classification (AC) algorithms typically search for all possible association rules to find a representative subset of those rules. Since the search space of such rules may grow exponentially as the support threshold decreases, the rules discovery process can be computationally expensive. One effective way to tackle this problem ...
Avila Daile - - 2012
In this work we apply a mathematical model of photosynthesis to quantify the potential for photosynthetic life in the very Early Archean oceans. We assume the presence of oceanic blockers of ultraviolet radiation, specifically ferrous ions. For this scenario, our results suggest a potential for photosynthetic life greater than or ...
Teschendorff Andrew E - - 2012
MOTIVATION: The Illumina Infinium 450k DNA Methylation Beadchip is a prime candidate technology for Epigenome-Wide Association Studies (EWAS). However, a difficulty associated with these beadarrays is that probes come in two different designs, characterised by widely different DNA methylation distributions and dynamic range, which may bias downstream analyses. A key ...
Hu Haipeng - - 2012
Abstract: We describe the application of different methods in the development of QSAR models for IKKA and IKKB inhibition. The results show that the best QSAR models provide highly accurate predictions for existing IKK inhibitors. The exceptions, corresponding to 5% of the known collection of inhibitors, are five classes of ...
Xu Weixin - - 2012
The structural characterization of amyloid fibers is one of the most investigated areas in structural biology. Recently, protofibril models for amylin, i.e., the 37-residue human islet amyloid polypeptide or hIAPP were suggested by two groups based on NMR (Luca et al., Biochemistry 2007;46:13505-13522) and X-ray (Wiltzius et al., Protein Sci ...
Marreiros André C - - 2012
Parkinson's disease is a common and debilitating condition, caused by aberrant activity in a complex basal ganglia-thalamocortical circuit. Therapeutic advances rely on characterising interactions in this circuit. However, recording electrophysiological responses over the entire circuit is impractical. Dynamic causal modelling offers large-scale models of predictive value based on a limited ...
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