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https://www.readbyqxmd.com/read/28214936/an-assessment-of-strontium-sorption-onto-bentonite-buffer-material-in-waste-repository
#1
Pankaj Pathak
In the present study, changes occurring in sorption characteristics of a representative bentonite (WIn-BT) exposed to SrCl2 (0.001-0.1 M) under the pH range of 1-13 were investigated. Such interaction revealed a significant variation in surface charge density and binding energy of ions with respect to bentonite, and alteration in their physicochemical properties viz., specific surface area, cation exchange capacity, thermal and mechanical behaviour were observed. The distribution coefficients (k d) calculated for sorption onto virgin (UCBT) and contaminated bentonite (CBT) indicated a greater influence of mineralogical changes occurred with variance of pH and strontium concentration...
February 18, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28214368/evaluation-of-deformable-image-registration-between-external-beam-radiotherapy-and-hdr-brachytherapy-for-cervical-cancer-with-a-3d-printed-deformable-pelvis-phantom
#2
Noriyuki Kadoya, Yuya Miyasaka, Yujiro Nakajima, Yoshihiro Kuroda, Kengo Ito, Mizuki Chiba, Kiyokazu Sato, Suguru Dobashi, Takaya Yamamoto, Noriyoshi Takahashi, Masaki Kubozono, Ken Takeda, Keiichi Jingu
PURPOSE: In this study, we developed a 3D-printed deformable pelvis phantom for evaluating spatial DIR accuracy. We then evaluated the spatial DIR accuracies of various DIR settings for cervical cancer. METHODS: A deformable female pelvis phantom was created based on patient CT data using 3D printing. To create the deformable uterus phantom, we first 3D printed both a model of uterus and a model of the internal cavities of the vagina and uterus. We then made a mold using the 3D printed uterus phantom...
February 18, 2017: Medical Physics
https://www.readbyqxmd.com/read/28214192/land-use-regression-with-long-term-satellite-based-greenness-index-and-culture-specific-sources-to-model-pm2-5-spatial-temporal-variability
#3
Chih-Da Wu, Yu-Cheng Chen, Wen-Chi Pan, Yu-Ting Zeng, Mu-Jean Chen, Yue Leon Guo, Shih-Chun Candice Lung
This study utilized a long-term satellite-based vegetation index, and considered culture-specific emission sources (temples and Chinese restaurants) with Land-use Regression (LUR) modelling to estimate the spatial-temporal variability of PM2.5 using data from Taipei metropolis, which exhibits typical Asian city characteristics. Annual average PM2.5 concentrations from 2006 to 2012 of 17 air quality monitoring stations established by Environmental Protection Administration of Taiwan were used for model development...
February 14, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28213546/environmental-surveillance-of-norovirus-genogroups-i-and-ii-for-sensitive-detection-of-epidemic-variants
#4
Shinobu Kazama, Takayuki Miura, Yoshifumi Masago, Yoshimitsu Konta, Kentaro Tohma, Takafumi Manaka, Xiaofang Liu, Daisuke Nakayama, Takashi Tanno, Mayuko Saito, Hitoshi Oshitani, Tatsuo Omura
Sewage samples have been investigated to study the level of noroviruses concentration in sewage or the genotypes of noroviruses circulating in human populations. However, the statistical relationship between the concentration of the virus and the number of infected individuals, and the clinical importance of genotypes or strains detected in sewage are unclear. In this study, we carried out both environmental and clinical surveillance of noroviruses for three years: 2013-2016. We performed cross-correlation analysis between the concentrations of norovirus GI or GII in sewage samples collected weekly and the number of gastroenteritis cases...
February 17, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28213403/temporal-dissociation-between-minimal-distal-to-aortic-pressure-ratio-and-peak-hyperemia-during-intravenous-adenosine-infusion
#5
Lorena Casadonte, Koen M Marques, Jos Ae Spaan, Maria Siebes
The present study sought to compare the temporal relation between maximal coronary flow (peak hyperemia) and minimal coronary/aortic (Pd/Pa) pressure ratio for intracoronary (IC) and intravenous (IV) adenosine administration. Peak hyperemia is assumed to coincide with the minimal Pd/Pa value. However, this has not been confirmed for systemic hemodynamic variations during IV adenosine infusion. Hemodynamic responses to IV and IC adenosine administration were obtained in 12 patients (14 lesions) using combined intracoronary pressure and flow velocity measurements...
February 17, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/28213206/selected-aspects-of-prior-and-likelihood-information-for-a-bayesian-classifier-in-a-road-safety-analysis
#6
Marzena Nowakowska
The development of the Bayesian logistic regression model classifying the road accident severity is discussed. The already exploited informative priors (method of moments, maximum likelihood estimation, and two-stage Bayesian updating), along with the original idea of a Boot prior proposal, are investigated when no expert opinion has been available. In addition, two possible approaches to updating the priors, in the form of unbalanced and balanced training data sets, are presented. The obtained logistic Bayesian models are assessed on the basis of a deviance information criterion (DIC), highest probability density (HPD) intervals, and coefficients of variation estimated for the model parameters...
February 14, 2017: Accident; Analysis and Prevention
https://www.readbyqxmd.com/read/28212386/comparison-of-theoretical-and-experimental-values-for-plant-uptake-of-pesticide-from-soil
#7
Jeong-In Hwang, Sung-Eun Lee, Jang-Eok Kim
Pesticides that persist in soils may be taken up by the roots of plants. One way to assess plant uptake is to theoretically predict the extent of plant uptake using a mathematical model. In this study, a model was developed to predict plant uptake of pesticide residues in soils using various parameters, such as pesticide mobility within soil, plant transpiration stream, root-soil transfer rate, plant growth, and pesticide dissipation in either soils or plants. The accuracy of the model was evaluated by comparing the modeled concentrations with measured uptake concentrations of chlorpyrifos (CP) in lettuce, grown on treated soils with concentrations of approximately 10 and 20 mg kg-1 CP...
2017: PloS One
https://www.readbyqxmd.com/read/28212266/individual-patterns-in-blood-borne-indicators-of-fatigue-trait-or-chance
#8
Ross Julian, Tim Meyer, Hugh H K Fullagar, Sabrina Skorski, Mark Pfeiffer, Michael Kellmann, Alexander Ferrauti, Anne Hecksteden
Julian, R, Meyer, T, Fullagar, HHK, Skorski, S, Pfeiffer, M, Kellmann, M, Ferrauti, A, and Hecksteden, A. Individual patterns in blood-borne indicators of fatigue-trait or chance. J Strength Cond Res 31(3): 608-619, 2017-Blood-borne markers of fatigue such as creatine kinase (CK) and urea (U) are widely used to fine-tune training recommendations. However, predictive accuracy is low. A possible explanation for this dissatisfactory characteristic is the propensity of athletes to react to different patterns of fatigue indicators (e...
March 2017: Journal of Strength and Conditioning Research
https://www.readbyqxmd.com/read/28211700/from-genotype-to-phenotype-cytochrome-p450-2d6-mediated-drug-clearance-in-humans
#9
Jie Gao, Xin Tian, Jun Zhou, Ming-Zhu Cui, Hai-Feng Zhang, Na Gao, Qiang Wen, Hai-Ling Qiao
How genotypic variation results in phenotypic differences is still a challenge for biology. In the field of drug metabolism the means by which specific cytochrome P4502D6 (CYP2D6) genotypes yield different phenotypes at various levels (molecular, cellular, and organismal) is an important question, as differences in CYP2D6 activity can contribute to adverse drug reactions. Herein, the genotype of CYP2D6 was determined along with the absolute content of CYP2D6 and microsomal protein per gram of liver in human liver microsomes, the molecular, cellular (microsomal, tissue, organ), and organismal phenotype of CYP2D6 determined; the effect of genotype on each phenotype of CYP2D6-mediated dextromethorphan clearance (CL) was delineated, and the overall genotype-phenotype relationship for CYP2D6 was charted...
February 17, 2017: Molecular Pharmaceutics
https://www.readbyqxmd.com/read/28211085/variable-selection-in-the-functional-linear-concurrent-model
#10
Jeff Goldsmith, Joseph E Schwartz
We propose methods for variable selection in the context of modeling the association between a functional response and concurrently observed functional predictors. This data structure, and the need for such methods, is exemplified by our motivating example: a study in which blood pressure values are observed throughout the day, together with measurements of physical activity, location, posture, affect or mood, and other quantities that may influence blood pressure. We estimate the coefficients of the concurrent functional linear model using variational Bayes and jointly model residual correlation using functional principal components analysis...
February 17, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/28210343/reliability-and-factorial-validity-of-non-specific-and-tennis-specific-pre-planned-agility-tests-preliminary-analysis
#11
Damir Sekulic, Ognjen Uljevic, Mia Peric, Miodrag Spasic, Miran Kondric
Agility is an important quality in tennis, yet there is an evident lack of studies focussing on the applicability of tennis-specific agility performances and comparing them to equivalent non-specific agility performances. The aim of this study was to evaluate the reliability and factorial validity of three tests of pre-planned agility, performed in specific (with a tennis racquet) and non-specific (without a tennis racquet) conditions. The sample consisted of 33 tennis players (13 males and 20 females; age: 18...
January 1, 2017: Journal of Human Kinetics
https://www.readbyqxmd.com/read/28209283/community-audit-of-social-civil-and-activity-domains-in-diverse-environments-cascadde
#12
Emily A Knapp, Claudia Nau, Sy Brandau, Joseph DeWalle, Annemarie G Hirsch, Lisa Bailey-Davis, Brian S Schwartz, Thomas A Glass
There are currently no direct observation environmental audit tools that measure diverse aspects of the obesity-related environment efficiently and reliably in a variety of geographic settings. The goal was to develop a new instrument to reliably characterize the overall properties and features of rural, suburban, and urban settings along multiple dimensions. The Community Audit of Social, Civil, and Activity Domains in Diverse Environments (CASCADDE) is an iPad-based instrument that incorporates GPS coordinates and photography and comprises 214 items yielding seven summary indices...
February 10, 2017: American Journal of Preventive Medicine
https://www.readbyqxmd.com/read/28209163/cardiovascular-magnetic-resonance-myocardial-feature-tracking-using-a-non-rigid-elastic-image-registration-algorithm-assessment-of-variability-in-a-real-life-clinical-setting
#13
Pedro Morais, Alberto Marchi, Julie A Bogaert, Tom Dresselaers, Brecht Heyde, Jan D'hooge, Jan Bogaert
BACKGROUND: Cardiovascular magnetic resonance myocardial feature tracking (CMR-FT) is a promising technique for quantification of myocardial strain from steady-state free precession (SSFP) cine images. We sought to determine the variability of CMR-FT using a non-rigid elastic registration algorithm recently available in a commercial software package (Segment, Medviso) in a real-life clinical setting. METHODS: Firstly, we studied the variability in a healthy volunteer who underwent 10 CMR studies over five consecutive days...
February 17, 2017: Journal of Cardiovascular Magnetic Resonance
https://www.readbyqxmd.com/read/28208506/self-diffusion-in-two-dimensional-binary-colloidal-hard-sphere-fluids
#14
Alice L Thorneywork, Dirk G A L Aarts, Jürgen Horbach, Roel P A Dullens
We present a systematic experimental study of the dynamic behavior of monodisperse and bidisperse two-dimensional colloidal hard-sphere fluids. We consider the diffusive behavior of the two types of particles for systems with a variety of compositions and total area fractions. In particular, we measure the short- and long-time diffusion coefficients for both species independently. We find that the short-time self-diffusion coefficients show an approximately linear dependence on the area fraction and that the long-time self-diffusion coefficients are well described by an expression dependent upon only the area fraction and contact value of the radial distribution function...
January 2017: Physical Review. E
https://www.readbyqxmd.com/read/28207950/simplifying-volumes-of-interest-vois-definition-in-quantitative-spect-beyond-manual-definition-of-3d-whole-organ-vois
#15
Esther M Vicente, Martin A Lodge, Steven P Rowe, Richard L Wahl, Eric C Frey
PURPOSE: We investigated the feasibility of using simpler methods than manual whole-organ volume-of-interest (VOI) definition to estimate the organ activity concentration in single photon emission computed tomography (SPECT) in cases where the activity in the organ can be assumed to be uniformly distributed on the scale of the voxel size. In particular, we investigated an anatomic region-of-interest (ROI) defined in a single transaxial slice, and a single sphere placed inside the organ boundaries...
February 16, 2017: Medical Physics
https://www.readbyqxmd.com/read/28207874/growth-and-life-history-variability-of-the-grey-reef-shark-carcharhinus-amblyrhynchos-across-its-range
#16
Darcy Bradley, Eric Conklin, Yannis P Papastamatiou, Douglas J McCauley, Kydd Pollock, Bruce E Kendall, Steven D Gaines, Jennifer E Caselle
For broadly distributed, often overexploited species such as elasmobranchs (sharks and rays), conservation management would benefit from understanding how life history traits change in response to local environmental and ecological factors. However, fishing obfuscates this objective by causing complex and often mixed effects on the life histories of target species. Disentangling the many drivers of life history variability requires knowledge of elasmobranch populations in the absence of fishing, which is rarely available...
2017: PloS One
https://www.readbyqxmd.com/read/28205347/robust-universal-nonrigid-motion-correction-framework-for-first-pass-cardiac-mr-perfusion-imaging
#17
Mitchel Benovoy, Matthew Jacobs, Farida Cheriet, Nagib Dahdah, Andrew E Arai, Li-Yueh Hsu
PURPOSE: To present and assess an automatic nonrigid image registration framework that compensates motion in cardiac magnetic resonance imaging (MRI) perfusion series and auxiliary images acquired under a wide range of conditions to facilitate myocardial perfusion quantification. MATERIALS AND METHODS: Our framework combines discrete feature matching for large displacement estimation with a dense variational optical flow formulation in a multithreaded architecture...
February 15, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28205306/multi-site-quality-and-variability-analysis-of-3d-fdg-pet-segmentations-based-on-phantom-and-clinical-image-data
#18
Reinhard R Beichel, Brian J Smith, Christian Bauer, Ethan J Ulrich, Payam Ahmadvand, Mikalai M Budzevich, Robert J Gillies, Dmitry Goldgof, Milan Grkovski, Ghassan Hamarneh, Qiao Huang, Paul E Kinahan, Charles M Laymon, James M Mountz, John P Muzi, Mark Muzi, Sadek Nehmeh, Matthew J Oborski, Yongqiang Tan, Binsheng Zhao, John J Sunderland, John M Buatti
PURPOSE: Radiomics utilizes a large number of image-derived features for quantifying tumor characteristics that can in turn be correlated with response and prognosis. Unfortunately, extraction and analysis of such image-based features is subject to measurement variability and bias. The challenge for radiomics is particularly acute in Positron Emission Tomography (PET) where limited resolution, a high noise component related to the limited stochastic nature of the raw data, and the wide variety of reconstruction options confound quantitative feature metrics...
February 2017: Medical Physics
https://www.readbyqxmd.com/read/28205280/within-and-between-session-reproducibility-of-gaba-measurements-with-mr-spectroscopy
#19
Maiken K Brix, Lars Ersland, Kenneth Hugdahl, Gerard E Dwyer, Renate Grüner, Ralph Noeske, Mona K Beyer, Alexander R Craven
PURPOSE: The reproducibility of the MEGA-PRESS (MEshcher-GArwood Point RESolved Spectroscopy) MR spectroscopy sequence for the measurement of gamma- aminobutyric acid (GABA) is addressed, focusing on optimizing the number of repetitions at two voxel locations in the human brain and associated possibilities in analysis tools. MATERIALS AND METHODS: Two 20-min MEGA-PRESS acquisitions were run (echo time = 68 ms, repetition time = 1800 ms, repetitions = 328): one from a 21 mL volume in the anterior cingulate cortex (ACC) and one from a 22 mL volume in the left Broca's area in 21 healthy male volunteers (age 32 years ± 6[SD])...
February 15, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28203619/variation-in-the-response-of-eastern-and-southern-africa-provenances-of-faidherbia-albida-delile-a-chev-seedlings-to-water-supply-a-greenhouse-experiment
#20
Grace Koech, Daniel Ofori, Anne W T Muigai, Jonathan Muriuki, Parveen Anjarwalla, Jan De Leeuw, Jeremias G Mowo
Rural communities value Faidherbia albida in farming systems and pastoralism. Faidherbia albida provides products such as medicine, fodder, fuel, wood, food and services such as shade, soil fertility and nutrient cycling. Excessive browsing by animals, branch lopping and pod harvesting, have critically reduced the natural regeneration in some areas which exposes it to challenges due to dependence upon natural regeneration. The objective of this research was to evaluate response of Faidherbia albida provenances from eastern (Taveta Wangingombe) and southern Africa (Lupaso, Kuiseb Manapools) to different watering regimes to aid in selection of provenances for domestication...
October 2016: Global Ecology and Conservation
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