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https://www.readbyqxmd.com/read/28651391/-prevalence-of-myopia-and-increase-trend-in-children-and-adolescents-aged-7-18-years-in-han-ethnic-group-in-china-2005-2014
#1
Y H Dong, H B Liu, Z H Wang, Z P Yang, R B Xu, Z G Yang, J Ma
Objective: To understand and evaluate the prevalence of myopia and its trend in children and adolescents aged 7-18 years in Han ethnic group in China from 2005 to 2014, and provide evidence for the prevention of myopia. Methods: The data of 2005, 2010 and 2014 Chinese National Students Constitution and Health Surveys were collected. The children and adolescents with complete detection data of binoculus were selected as study subjects. The sample size of three studies were 233 108, 215 319 and 212 743, respectively...
May 10, 2017: Zhonghua Liu Xing Bing Xue za Zhi, Zhonghua Liuxingbingxue Zazhi
https://www.readbyqxmd.com/read/28651376/comparison-of-sampling-strategies-for-tobacco-retailer-inspections-to-maximize-coverage-in-vulnerable-areas-and-minimize-cost
#2
Joseph G L Lee, Bonnie E Shook-Sa, J Michael Bowling, Kurt M Ribisl
Introduction: In the United States, tens of thousands of inspections of tobacco retailers are conducted each year. Various sampling choices can reduce travel costs, emphasize enforcement in areas with greater non-compliance, and allow for comparability between states and over time. We sought to develop a model sampling strategy for state tobacco retailer inspections. Methods: Using a 2014 list of 10,161 North Carolina tobacco retailers, we compared results from simple random sampling; stratified, clustered at the ZIP code sampling; and, stratified, clustered at the census tract sampling...
June 23, 2017: Nicotine & Tobacco Research: Official Journal of the Society for Research on Nicotine and Tobacco
https://www.readbyqxmd.com/read/28651334/tsgsis-a-high-dimensional-grouped-variable-selection-approach-for-detection-of-whole-genome-snp-snp-interactions
#3
Yao-Hwei Fang, Jie-Huei Wang, Chao A Hsiung
Motivation: Identification of single nucleotide polymorphism (SNP) interactions is an important and challenging topic in genome-wide association studies (GWAS). Many approaches have been applied to detecting whole-genome interactions. However, these approaches to interaction analysis tend to miss causal interaction effects when the individual marginal effects are uncorrelated to trait, while their interaction effects are highly associated with the trait. Results: A grouped variable selection technique, called two-stage grouped sure independence screening (TS-GSIS), is developed to study interactions that may not have marginal effects...
June 23, 2017: Bioinformatics
https://www.readbyqxmd.com/read/28651318/fate-of-polycyclic-aromatic-hydrocarbons-from-the-north-pacific-to-the-arctic-field-measurements-and-fugacity-model-simulation
#4
Hongwei Ke, Mian Chen, Mengyang Liu, Meng Chen, Mengshan Duan, Peng Huang, Jiajun Hong, Yan Lin, Shayen Cheng, Xuran Wang, Mengxue Huang, Minggang Cai
Polycyclic aromatic hydrocarbons (PAHs) have accumulated ubiquitously inArctic environments, where re-volatilization of certain organic pollutants as a result of climate change has been observed. To investigate the fate of semivolatile organic compounds in the Arctic, dissolved PAHs in the surface seawaters from the temperate Pacific Ocean to the Arctic Ocean, as well as a water column in the Arctic Ocean, were collected during the 4th Chinese National Arctic Research Expedition in summer 2010. The total concentrations of seven dissolved PAHs in surface water ranged from 1...
June 16, 2017: Chemosphere
https://www.readbyqxmd.com/read/28651217/modeling-in-sewer-transformations-at-catchment-scale-implications-on-drug-consumption-estimates-in-wastewater-based-epidemiology
#5
Ann-Kathrin McCall, Rocco Palmitessa, Frank Blumensaat, Eberhard Morgenroth, Christoph Ort
To which extent illicit drugs are transformed during in-sewer transport, depends on a number of factors: i) substance-specific transformation rates, ii) environmental conditions, iii) point of discharge (location of drug user) and iv) sewer network properties, primarily hydraulic residence time (HRT) and the ratio of biofilm contact area to wastewater volume (A/Veq). Assessing associated uncertainties typically requires numerous simulations. Therefore, we propose a new two-step modeling framework: 1) Quantify hydrodynamic conditions...
May 20, 2017: Water Research
https://www.readbyqxmd.com/read/28651099/brain-shift-compensation-using-intraoperative-ultrasound-and-constraint-based-biomechanical-simulation
#6
Fanny Morin, Hadrien Courtecuisse, Ingerid Reinertsen, Florian Le Lann, Olivier Palombi, Yohan Payan, Matthieu Chabanas
PURPOSE: During brain tumor surgery, planning and guidance are based on preoperative images which do not account for brain-shift. However, this deformation is a major source of error in image-guided neurosurgery and affects the accuracy of the procedure. In this paper, we present a constraint-based biomechanical simulation method to compensate for craniotomy-induced brain-shift that integrates the deformations of the blood vessels and cortical surface, using a single intraoperative ultrasound acquisition...
June 15, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28651056/significantly-improved-protein-folding-thermodynamics-using-a-dispersion-corrected-water-model-and-a-new-residue-specific-force-field
#7
Hao-Nan Wu, Fan Jiang, Yun-Dong Wu
An accurate potential energy model is crucial for biomolecular simulations. Despite many recent improvements of classical protein force fields, there are remaining key issues: much weaker temperature-dependence of folding/unfolding equilibrium, and overly collapsed unfolded or disordered states. For the later problem, a new water model (TIP4P-D) has been proposed to correct the significantly underestimated water dispersion interactions. Here, using TIP4P-D, we reveal problems in current force fields through failures in folding model systems (a polyalanine peptide, Trp-cage and the GB1 hairpin)...
June 26, 2017: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/28651045/photoinduced-charge-transfer-versus-fragmentation-pathways-in-lanthanum-cyclopentadienyl-complexes
#8
Yulun Han, Qingguo Meng, Bakhtiyor Rasulev, P Stanley May, Mary T Berry, Dmitri S Kilin
This study compares two competing pathways of photoexcitations in gas-phase metal-organic complexes: first, a sequence of phonon-assisted electronic transitions leading to dissipation of the energy of photoexcitations and second, a sequence of light-driven electronic transitions leading to photolysis. Phonon-assisted charge carrier dynamics is investigated by combination of the density matrix formalism and on-the-fly nonadiabatic couplings. Light-driven fragmentation is modeled by a time-dependent excited-state molecular dynamics (TDESMD) algorithm based on Rabi theory and principles similar to the trajectory surface hopping approximation...
June 26, 2017: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/28650962/novel-inference-models-for-estimation-of-abundance-survivorship-and-recruitment-in-mosquito-populations-using-mark-release-recapture-data
#9
Daniel Antunes Maciel Villela, Gabriela de Azambuja Garcia, Rafael Maciel-de-Freitas
BACKGROUND: Experiments involving mosquito mark-release-recapture (MRR) design are helpful to determine abundance, survival and even recruitment of mosquito populations in the field. Obstacles in mosquito MRR protocols include marking limitations due to small individual size, short lifespan, low efficiency in capturing devices such as traps, and individual removal upon capture. These limitations usually make MRR analysis restricted to only abundance estimation or a combination of abundance and survivorship, and often generate a great degree of uncertainty about the estimations...
June 26, 2017: PLoS Neglected Tropical Diseases
https://www.readbyqxmd.com/read/28650846/dosimetric-verification-in-water-of-a-monte-carlo-treatment-planning-tool-for-proton-helium-carbon-and-oxygen-ion-beams-at-the-heidelberg-ion-beam-therapy-center
#10
Thomas Tessonnier, Till Tobias Boehlen, Francesco Cerutti, Alfredo Ferrari, Paola Roberta Sala, Stephan Brons, Thomas Haberer, Juergen Debus, Katia Parodi, Andrea Mairani
The introduction of "new" ion species in particle therapy needs to be supported by a thorough assessment of their dosimetric properties and by treatment planning comparisons with clinically used proton and carbon ion beams. In addition to the latter two ions, helium and oxygen ion beams are foreseen at the Heidelberg Ion beam Therapy (HIT) center as potential assets for improving clinical outcomes in the near future. We present in this study a dosimetric validation of a FLUKA-based Monte Carlo Treatment Planning tool (MCTP) for protons, helium, carbon and oxygen ions for spread-out Bragg peaks...
June 26, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28650829/time-varying-system-identification-using-an-ultra-orthogonal-forward-regression-and-multiwavelet-basis-functions-with-applications-to-eeg
#11
Yang Li, Wei-Gang Cui, Yu-Zhu Guo, Tingwen Huang, Xiao-Feng Yang, Hua-Liang Wei
A new parametric approach is proposed for nonlinear and nonstationary system identification based on a time-varying nonlinear autoregressive with exogenous input (TV-NARX) model. The TV coefficients of the TV-NARX model are expanded using multiwavelet basis functions, and the model is thus transformed into a time-invariant regression problem. An ultra-orthogonal forward regression (UOFR) algorithm aided by mutual information (MI) is designed to identify a parsimonious model structure and estimate the associated model parameters...
June 22, 2017: IEEE Transactions on Neural Networks and Learning Systems
https://www.readbyqxmd.com/read/28650820/terahertz-channel-model-and-link-budget-analysis-for-intrabody-nanoscale-communication
#12
Hadeel Elayan, Raed M Shubair, Josep M Jornet, Pedram Johari
Nanosized devices operating inside the human body open up new prospects in the healthcare domain. In vivo wireless nanosensor networks (iWNSNs) will result in a plethora of applications ranging from intrabody health-monitoring to drug- delivery systems. With the development of miniature plasmonic signal sources, antennas and detectors, wireless communications among intrabody nanodevices will expectedly be enabled at both the Terahertz Band (0.1-10 THz) as well as optical frequencies (400-750 THz). This result motivates the analysis of the phenomena affecting the propagation of electromagnetic signals inside the human body...
June 22, 2017: IEEE Transactions on Nanobioscience
https://www.readbyqxmd.com/read/28650774/monte-carlo-electron-track-structure-calculations-in-liquid-water-using-a-new-model-dielectric-response-function
#13
Dimitris Emfietzoglou, George Papamichael, Hooshang Nikjoo
Monte Carlo track structure codes provide valuable information for understanding radiation effects down to the DNA level, where experimental measurements are most difficult or unavailable. It is well recognized that the performance of such codes, especially at low energies and/or subcellular level, critically depends on the reliability of the interaction cross sections that are used as input in the simulation. For biological media such as liquid water, one of the most challenging issues is the role of condensed-phase effects...
June 26, 2017: Radiation Research
https://www.readbyqxmd.com/read/28650640/light-mediated-reactive-oxygen-species-generation-and-iron-redox-transformations-in-the-presence-of-exudate-from-the-cyanobacterium-microcystis-aeruginosa
#14
Kai Wang, Shikha Garg, T David Waite
The photochemical properties of the organic exudate secreted by a toxic strain of Microcystis aeruginosa were studied by measuring reactive oxygen species (ROS) generation and redox transformations of iron in the presence of the organic exudate under acidic (pH 4) and alkaline (pH 8) conditions. Our results show that the organic exudate generates nanomolar concentrations of superoxide and hydrogen peroxide on irradiation with simulated sunlight in a manner consistent with that reported for terrigenous natural organic matter...
June 26, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28650562/the-economic-value-of-hybrid-single-photon-emission-computed-tomography-with-computed-tomography-imaging-in-pulmonary-embolism-diagnosis
#15
Lauren K Toney, Richard D Kim, Swetha R Palli
OBJECTIVE: To quantify the potential economic value of single-photon emission computed tomography (SPECT) with computed tomography (CT; SPECT/CT) versus CT pulmonary angiography (CTPA), ventilation-perfusion (V/Q) planar scintigraphy and V/Q SPECT imaging modalities for diagnosing suspected pulmonary embolism (PE) patients in an emergency setting. METHODS: An Excel-based simulation model was developed to compare SPECT/CT versus the alternate scanning technologies from a payer's perspective...
June 26, 2017: Academic Emergency Medicine: Official Journal of the Society for Academic Emergency Medicine
https://www.readbyqxmd.com/read/28650363/population-pharmacokinetics-and-pharmacodynamic-target-attainment-of-vancomycin-in-neonates-on-extracorporeal-life-support
#16
Jeffrey J Cies, Wayne S Moore, Kristen Nichols, Chad A Knoderer, Dominick M Carella, Arun Chopra
OBJECTIVES: To evaluate the population pharmacokinetics and pharmacodynamic target attainment of vancomycin in neonates with a contemporary ¼-inch extracorporeal life support circuit with a Quadrox-iD Pediatric oxygenator (Maquet Cardiovascular, LLC, Wayne, NJ). DESIGN: Retrospective medical record review. SETTING: Two free-standing tertiary/quaternary pediatric children's hospitals. PATIENTS: Neonates receiving either veno-arterial or veno-venous extracorporeal life support and vancomycin for empiric or definitive therapy with resulting serum concentrations...
June 22, 2017: Pediatric Critical Care Medicine
https://www.readbyqxmd.com/read/28650174/dissolution-processes-at-step-edges-of-calcite-in-water-investigated-by-high-speed-frequency-modulation-atomic-force-microscopy-and-simulation
#17
Kazuki Miyata, John Tracey, Keisuke Miyazawa, Ville Anton Haapasilta, Peter Spijker, Yuta Kawagoe, Adam S Foster, Katsuo Tsukamoto, Takeshi Fukuma
The microscopic understanding of the crystal growth and dissolution processes have been greatly advanced by the direct imaging of nanoscale step flows by atomic force microscopy (AFM), optical interferometry and x-ray microscopy. However, one of the most fundamental events that govern their kinetics, namely, atomistic events at the step edges have not been well understood. In this study, we have developed high-speed frequency modulation AFM (FM-AFM) and enabled true atomic-resolution imaging in liquid at ~1 s/frame, which is ~50 times faster than the conventional FM-AFM...
June 26, 2017: Nano Letters
https://www.readbyqxmd.com/read/28650112/liver-graft-preservation-using-perfluorocarbon-improves-the-outcomes-of-simulated-donation-after-cardiac-death-liver-transplantation-in-rats
#18
Shinya Okumura, Tadahiro Uemura, Xiangdong Zhao, Yuki Masano, Tatsuaki Tsuruyama, Yasuhiro Fujimoto, Taku Iida, Shintaro Yagi, Dmitri Bezinover, Bruce Spiess, Toshimi Kaido, Shinji Uemoto
INTRODUCTION: The outcomes of liver transplantation from donation after cardiac death (DCD) donors remain poor due to the severe warm ischemic injury. Perfluorocarbon (PFC) is a novel compound with high oxygen carrying capacity. In the present study, a rat model simulating DCD liver transplantation was used, and the impact of improved graft oxygenation provided by PFC addition on liver ischemia-reperfusion injury (IRI) and survival after DCD liver transplantation was investigated. MATERIAL AND METHODS: Orthotopic liver transplants were performed in male Lewis rats, using DCD liver grafts preserved with cold University of Wisconsin (UW) solution in the control group and preserved with cold oxygenated UW solution with addition of 20% PFC in the PFC group...
June 26, 2017: Liver Transplantation
https://www.readbyqxmd.com/read/28650086/systemic-thrombolysis-catheter-directed-thrombolysis-and-anticoagulation-for-intermediate-risk-pulmonary-embolism-a-simulation-modeling-analysis
#19
Christopher Kabrhel, Ayman Ali, Jin Choi, Chin Hur
OBJECTIVES: Decision-making around the use of thrombolysis for patients with intermediate-risk (submassive) PE remains challenging. Studies indicate favorable clinical outcomes with systemic thrombolytics (IV tPA), but the risk of major bleeding and hemorrhagic stroke is a deterrent. Catheter-directed thrombolysis (CDT) may be a preferable strategy, as it has been shown to have a lower risk of bleeding than systemic thrombolysis. However, a three-arm randomized control study comparing IV tPA, CDT, and anticoagulation alone, with long-term follow up, would be costly and is unlikely to be performed...
June 26, 2017: Academic Emergency Medicine: Official Journal of the Society for Academic Emergency Medicine
https://www.readbyqxmd.com/read/28649977/convection-shapes-the-trade-off-between-antibiotic-efficacy-and-the-selection-for-resistance-in-spatial-gradients
#20
Matti Gralka, Diana Fusco, Stephen Martis, Oskar Hallatschek
Since penicillin was discovered about 90 years ago, we have become used to using drugs to eradicate unwanted pathogenic cells. However, using drugs to kill bacteria, viruses or cancer cells has the serious side effect of selecting for mutant types that survive the drug attack. A key question therefore is how one could eradicate as many cells as possible for a given acceptable risk of drug resistance evolution. We address this general question in a model of drug resistance evolution in spatial drug gradients, which recent experiments and theories have suggested as key drivers of drug resistance...
June 26, 2017: Physical Biology
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