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https://www.readbyqxmd.com/read/27930684/comparison-of-contaminant-transport-in-agricultural-drainage-water-and-urban-stormwater-runoff
#1
Ehsan Ghane, Andry Z Ranaivoson, Gary W Feyereisen, Carl J Rosen, John F Moncrief
Transport of nitrogen and phosphorus from agricultural and urban landscapes to surface water bodies can cause adverse environmental impacts. The main objective of this long-term study was to quantify and compare contaminant transport in agricultural drainage water and urban stormwater runoff. We measured flow rate and contaminant concentration in stormwater runoff from Willmar, Minnesota, USA, and in drainage water from subsurface-drained fields with surface inlets, namely, Unfertilized and Fertilized Fields...
2016: PloS One
https://www.readbyqxmd.com/read/27929510/deriving-detector-specific-correction-factors-for-rectangular-small-fields-using-a-scintillator-detector
#2
Yujiao Qin, Hualiang Zhong, Ning Wen, Karen Snyder, Yimei Huang, Indrin J Chetty
The goal of this study was to investigate small field output factors (OFs) for flat-tening filter-free (FFF) beams on a dedicated stereotactic linear accelerator-based system. From this data, the collimator exchange effect was quantified, and detector-specific correction factors were generated. Output factors for 16 jaw-collimated small fields (from 0.5 to 2 cm) were measured using five different detectors including an ion chamber (CC01), a stereotactic field diode (SFD), a diode detector (Edge), Gafchromic film (EBT3), and a plastic scintillator detector (PSD, W1)...
November 8, 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/27929502/epid-based-dosimetry-to-verify-imrt-planar-dose-distribution-for-the-as1200-epid-and-fff-beams
#3
Narges Miri, Peter Keller, Benjamin J Zwan, Peter Greer
We proposed to perform a basic dosimetry commissioning on a new imager sys-tem, the Varian aS1200 electronic portal imaging device (EPID) and TrueBeam 2.0 linear accelerator for flattened (FF) and flattening filter-free (FFF) beams, then to develop an image-based quality assurance (QA) model for verification of the system delivery accuracy for intensity-modulated radiation therapy (IMRT) treat-ments. For dosimetry testing, linearity of dose response with MU, imager lag, and effectiveness of backscatter shielding were investigated...
November 8, 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/27929496/experimental-evaluation-of-a-gpu-based-monte-carlo-dose-calculation-algorithm-in-the-monaco-treatment-planning-system
#4
Moti R Paudel, Anthony Kim, Arman Sarfehnia, Sayed B Ahmad, David J Beachey, Arjun Sahgal, Brian M Keller
A new GPU-based Monte Carlo dose calculation algorithm (GPUMCD), devel-oped by the vendor Elekta for the Monaco treatment planning system (TPS), is capable of modeling dose for both a standard linear accelerator and an Elekta MRI linear accelerator. We have experimentally evaluated this algorithm for a standard Elekta Agility linear accelerator. A beam model was developed in the Monaco TPS (research version 5.09.06) using the commissioned beam data for a 6 MV Agility linac. A heterogeneous phantom representing several scenarios - tumor-in-lung, lung, and bone-in-tissue - was designed and built...
November 8, 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/27929489/clinically-relevant-investigation-of-flattening-filter-free-skin-dose
#5
Christopher L Guy, Kishor Karki, Manju Sharma, Siyong Kim
As flattening filter-free (FFF) photon beams become readily available for treat-ment delivery in techniques such as SBRT, thorough investigation of skin dose from FFF photon beams is necessary under clinically relevant conditions. Using a parallel-plate PTW Markus chamber placed in a custom water-equivalent phantom, surface-dose measurements were taken at 2 × 2, 3 × 3, 4 × 4, 6 × 6, 8 × 8, 10 × 10, 20 × 20, and 30 × 30 cm2 field sizes, at 80, 90, and 100 cm source-to-surface distances (SSDs), and with fields defined by jaws and multileaf collimator (MLC) using multiple beam energies (6X, 6XFFF, 10X, and 10XFFF)...
November 8, 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/27928997/large-electrorheological-phenomena-in-graphene-nano-gels
#6
Purbarun Dhar, Ajay Katiyar, Arvind Pattamatta, Sarit K Das
Large-scale electrorheology (ER) response has been reported for dilute graphene nanoflake-based ER fluids that have been engineered as novel, readily synthesizable polymeric gels. Polyethylene glycol (PEG 400) based graphene gels have been synthesized and a very high ER response (∼125 000% enhancement in viscosity under influence of an electric field) has been observed for low concentration systems (∼2 wt.%). The gels overcome several drawbacks innate to ER fluids. The gels exhibit long term stability, a high graphene packing ratio which ensures very high ER response, and the microstructure of the gels ensures that fibrillation of the graphene nanoflakes under an electric field is undisturbed by thermal fluctuations, further leading to mega ER...
December 8, 2016: Nanotechnology
https://www.readbyqxmd.com/read/27927875/three-dimensional-characterization-of-guinier-preston-zones-in-an-al-cu-alloy-using-depth-sectioning-technique
#7
Takumi Hamaoka, Chih-Yu Jao, Xiaobin Zhang, Yoshifumi Oshima, Masaki Takeguchi
Guinier-Preston (GP) zones formed as nanometer-sized Cu-rich monolayers in α-Al matrix phase during aging process have been investigated using depth-sectioning technique, where through-focal high-angle annular dark-field (HAADF) images were recorded along a <001> zone axis of the α-Al phase using aberration-corrected scanning transmission electron microscopy (STEM). HAADF intensities of the GP zones in the through-focal series vary with defocus settings, depending on the depths of the GP zones in the sample...
December 6, 2016: Microscopy
https://www.readbyqxmd.com/read/27925142/dg-connect-funded-projects-on-information-and-communication-technologies-ict-for-old-age-people-beyond-silos-carewell-and-smartcare
#8
W Keijser, E de Manuel-Keenoy, M d'Angelantonio, P Stafylas, P Hobson, G Apuzzo, M Hurtado, J Oates, J Bousquet, A Senn
Information and communication technologies (ICT) are promising for the long-term care of older and frequently frail people. These innovations can improve health outcomes, quality of life and efficiency of care processes, while supporting independent living. However, they may be disruptive innovations. As all European member states are facing an increasing complexity of health and social care, good practices in ICT should be identified and evaluated. Three projects funded by DG CNECT are related to Active and Healthy Ageing (AHA) and frailty: (i) BeyondSilos, dealing with independent living and integrated services, (ii) CareWell, providing integrated care coordination, patient empowerment and home support and (iii) SmartCare, proposing a common set of standard functional specifications for an ICT platform enabling the delivery of integrated care to older patients...
2016: Journal of Nutrition, Health & Aging
https://www.readbyqxmd.com/read/27924041/exposome-explorer-a-manually-curated-database-on-biomarkers-of-exposure-to-dietary-and-environmental-factors
#9
Vanessa Neveu, Alice Moussy, Héloïse Rouaix, Roland Wedekind, Allison Pon, Craig Knox, David S Wishart, Augustin Scalbert
Exposome-Explorer (http://exposome-explorer.iarc.fr) is the first database dedicated to biomarkers of exposure to environmental risk factors. It contains detailed information on the nature of biomarkers, their concentrations in various human biospecimens, the study population where measured and the analytical techniques used for measurement. It also contains correlations with external exposure measurements and data on biological reproducibility over time. The data in Exposome-Explorer was manually collected from peer-reviewed publications and organized to make it easily accessible through a web interface for in-depth analyses...
October 24, 2016: Nucleic Acids Research
https://www.readbyqxmd.com/read/27921431/-short-term-and-long-term-glycemic-variability-and-its-relationship-to-microvascular-complications-of-diabetes
#10
Martin Prázný, Jan Škrha, Jan Šoupal, Jan Škrha Jr
Vascular complications of diabetes result from long lasting unsatisfactory glycemic control. We usually assess glycemic control based on the value of glycated hemoglobin HbA1c. The glycated hemoglobin test, however, says nothing about short-term glycemic fluctuations. Recently, continuous monitoring of glycemia has enabled us an in-depth assessment of changes in glucose concentrations, called glycemic variability. In connection with the research into short-term glycemic variability, also the study of long-term fluctuations in glycemic control based on HbA1c variability has now intensified...
2016: Vnitr̆ní Lékar̆ství
https://www.readbyqxmd.com/read/27921069/reaching-200-ps-timing-resolution-in-a-time-of-flight-and-depth-of-interaction-positron-emission-tomography-detector-using-phosphor-coated-crystals-and-high-density-silicon-photomultipliers
#11
Sun Il Kwon, Alessandro Ferri, Alberto Gola, Eric Berg, Claudio Piemonte, Simon R Cherry, Emilie Roncali
Current research in the field of positron emission tomography (PET) focuses on improving the sensitivity of the scanner with thicker detectors, extended axial field-of-view, and time-of-flight (TOF) capability. These create the need for depth-of-interaction (DOI) encoding to correct parallax errors. We have proposed a method to encode DOI using phosphor-coated crystals. Our initial work using photomultiplier tubes (PMTs) demonstrated the possibilities of the proposed method, however, a major limitation of PMTs for this application is poor quantum efficiency in yellow light, corresponding to the wavelengths of the converted light by the phosphor coating...
October 2016: Journal of Medical Imaging
https://www.readbyqxmd.com/read/27918568/solution-based-electrical-doping-of-semiconducting-polymer-films-over-a-limited-depth
#12
Vladimir A Kolesov, Canek Fuentes-Hernandez, Wen-Fang Chou, Naoya Aizawa, Felipe A Larrain, Ming Wang, Alberto Perrotta, Sangmoo Choi, Samuel Graham, Guillermo C Bazan, Thuc-Quyen Nguyen, Seth R Marder, Bernard Kippelen
Solution-based electrical doping protocols may allow more versatility in the design of organic electronic devices; yet, controlling the diffusion of dopants in organic semiconductors and their stability has proven challenging. Here we present a solution-based approach for electrical p-doping of films of donor conjugated organic semiconductors and their blends with acceptors over a limited depth with a decay constant of 10-20 nm by post-process immersion into a polyoxometalate solution (phosphomolybdic acid, PMA) in nitromethane...
December 5, 2016: Nature Materials
https://www.readbyqxmd.com/read/27917528/the-ultimate-signal-to-noise-ratio-in-realistic-body-models
#13
Bastien Guérin, Jorge F Villena, Athanasios G Polimeridis, Elfar Adalsteinsson, Luca Daniel, Jacob K White, Lawrence L Wald
PURPOSE: We compute the ultimate signal-to-noise ratio (uSNR) and G-factor (uGF) in a realistic head model from 0.5 to 21 Tesla. METHODS: We excite the head model and a uniform sphere with a large number of electric and magnetic dipoles placed at 3 cm from the object. The resulting electromagnetic fields are computed using an ultrafast volume integral solver, which are used as basis functions for the uSNR and uGF computations. RESULTS: Our generalized uSNR calculation shows good convergence in the sphere and the head and is in close agreement with the dyadic Green's function approach in the uniform sphere...
December 4, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/27915179/axially-uniform-magnetic-field-modulation-excitation-for-electron-paramagnetic-resonance-in-rectangular-and-cylindrical-cavities-by-slot-cutting
#14
Jason W Sidabras, James E Richie, James S Hyde
In continuous-wave (CW) Electron Paramagnetic Resonance (EPR) a low-frequency time-harmonic magnetic field, called field modulation, is applied parallel to the static magnetic field and incident on the sample. Varying amplitude of the field modulation incident on the sample has consequences on spectral line-shape and line-height over the axis of the sample. Here we present a method of coupling magnetic field into the cavity using slots perpendicular to the sample axis where the slot depths are designed in such a way to produce an axially uniform magnetic field along the sample...
November 25, 2016: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/27915088/exploring-awareness-and-help-seeking-intentions-for-testicular-symptoms-among-heterosexual-gay-and-bisexual-men-in-ireland-a-qualitative-descriptive-study
#15
Mohamad M Saab, Margaret Landers, Josephine Hegarty
BACKGROUND: The incidence of malignant and benign testicular disorders among young men is on the rise. Evidence from three reviews suggest that men's knowledge of these disorders is lacking and their help-seeking intention for testicular symptoms is suboptimal. Qualitative studies have addressed men's awareness of testicular cancer, with none exploring their awareness of non-malignant diseases such as epididymitis, testicular torsion, and varicocele and none including sexual minorities...
November 28, 2016: International Journal of Nursing Studies
https://www.readbyqxmd.com/read/27914641/reduction-of-neonicotinoid-insecticide-residues-in-prairie-wetlands-by-common-wetland-plants
#16
Anson R Main, Jessica Fehr, Karsten Liber, John V Headley, Kerry M Peru, Christy A Morrissey
Neonicotinoid insecticides are frequently detected in wetlands during the early to mid-growing period of the Canadian Prairie cropping season. These detections also overlap with the growth of macrophytes that commonly surround agricultural wetlands which we hypothesized may reduce neonicotinoid transport and retention in wetlands. We sampled 20 agricultural wetlands and 11 macrophyte species in central Saskatchewan, Canada, over eight weeks to investigate whether macrophytes were capable of reducing movement of neonicotinoids from cultivated fields and/or reducing concentrations in surface water by accumulating insecticide residues into their tissues...
November 30, 2016: Science of the Total Environment
https://www.readbyqxmd.com/read/27913354/a-novel-elastic-force-field-to-influence-mediolateral-foot-placement-during-walking
#17
Elizabeth Nyberg, Jordan Broadway, Christian Finetto, Jesse Dean
Bipedal gait can be stabilized through mechanically-appropriate mediolateral foot placement, although this strategy is disrupted in a subset of neurologically injured individuals with balance deficits. The goal of the present work was to develop a device to influence mediolateral foot placement during treadmill walking. We created a novel force-field using a combination of passive elasticity and active control; wires in series with extension springs run parallel to the treadmill belts and can be rapidly repositioned to exert mediolateral forces on the legs of users...
December 1, 2016: IEEE Transactions on Neural Systems and Rehabilitation Engineering
https://www.readbyqxmd.com/read/27913329/2-d-ultrasound-sparse-arrays-multidepth-radiation-optimization-using-simulated-annealing-and-spiral-array-inspired-energy-functions
#18
Emmanuel Roux, Alessandro Ramalli, Piero Tortoli, Christian Cachard, Marc C Robini, Herve Liebgott
Full matrix arrays are excellent tools for 3-D ultrasound imaging, but the required number of active elements is too high to be individually controlled by an equal number of scanner channels. The number of active elements is significantly reduced by the sparse array techniques, but the position of the remaining elements must be carefully optimized. This issue is faced here by introducing novel energy functions in the simulated annealing (SA) algorithm. At each iteration step of the optimization process, one element is freely translated and the associated radiated pattern is simulated...
December 2016: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/27911778/enhanced-stochastic-fluctuations-to-measure-steep-adhesive-energy-landscapes
#19
Ahmad Haider, Daniel Potter, Todd A Sulchek
Free-energy landscapes govern the behavior of all interactions in the presence of thermal fluctuations in the fields of physical chemistry, materials sciences, and the biological sciences. From the energy landscape, critical information about an interaction, such as the reaction kinetic rates, bond lifetimes, and the presence of intermediate states, can be determined. Despite the importance of energy landscapes to understanding reaction mechanisms, most experiments do not directly measure energy landscapes, particularly for interactions with steep force gradients that lead to premature jump to contact of the probe and insufficient sampling of transition regions...
November 23, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27910597/note-attenuation-motion-of-acoustically-levitated-spherical-rotor
#20
P Lü, Z Y Hong, J F Yin, N Yan, W Zhai, H P Wang
Here we observe the attenuation motion of spherical rotors levitated by near-field acoustic radiation force and analyze the factors that affect the duration time of free rotation. It is found that the rotating speed of freely rotating rotor decreases exponentially with respect to time. The time constant of exponential attenuation motion depends mainly on the levitation height, the mass of rotor, and the depth of concave ultrasound emitter. Large levitation height, large mass of rotor, and small depth of concave emitter are beneficial to increase the time constant and hence extend the duration time of free rotation...
November 2016: Review of Scientific Instruments
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