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https://www.readbyqxmd.com/read/27929477/production-review-and-impact-of-technical-quality-control-guidelines-in-a-national-context
#1
Michelle K Nielsen, Kyle E Malkoske, Erika Brown, Kevin Diamond, Normand Frenière, John Grant, Natalie Pomerleau-Dalcourt, Jason Schella, L John Schreiner, Laurent Tantôt, J Eduardo Villareal-Barajas, Jean-Pierre Bissonnette
A close partnership between the Canadian Partnership for Quality Radiotherapy (CPQR) and the Canadian Organization of Medical Physicist's (COMP) Quality Assurance and Radiation Safety Advisory Committee (QARSAC) has resulted in the development of a suite of Technical Quality Control (TQC) guidelines for radiation treatment equipment; they outline specific performance objectives and criteria that equipment should meet in order to assure an acceptable level of radiation treatment quality. The adopted framework for the development and maintenance of the TQCs ensures the guidelines incorporate input from the medical physics com-munity during development, measures the workload required to perform the QC tests outlined in each TQC, and remain relevant (i...
November 8, 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/27925218/insights-into-light-driven-dna-repair-by-photolyases-challenges-and-opportunities-for-electronic-structure-theory
#2
Shirin Faraji, Andreas Dreuw
UV radiation causes two of the most abundant mutagenic and cytotoxic DNA lesions: cyclobutane pyrimidine dimers and 6-4 photoproducts. (6-4) photolyases are light-activated enzymes that selectively bind to DNA and trigger repair of mutagenic 6-4 photoproducts via photoinduced electron transfer from flavin adenine dinucleotide anion (FADH(-) ) to the lesion triggering repair. This review provides an overview of the sequential steps of the repair process, i.e. light absorption and resonance energy transfer, photo-induced electron transfer, and electron-induced splitting mechanisms, with an emphasis on the role of theory and computation...
December 7, 2016: Photochemistry and Photobiology
https://www.readbyqxmd.com/read/27918865/evidence-based-practice-in-the-management-of-lower-limb-lymphedema-after-gynecological-cancer
#3
Lisandra Fossari Iwersen, Fabiana Flores Sperandio, Ariana Machado Toriy, Marina Palú, Clarissa Medeiros da Luz
PURPOSE: Lower limb lymphedema (LLL) is characterized as a physical-functional chronic complication that impacts the quality of life of women who have gone through treatment for gynecological cancer. The present study aims to check the conservative treatments available for lymphedema after gynecological cancer in the context of evidence-based practice. METHODS: The selection criteria included papers from May 1993 discussing treatment protocols used in LLL after treatment for gynecological cancer...
December 5, 2016: Physiotherapy Theory and Practice
https://www.readbyqxmd.com/read/27917407/microwave-heating-of-synthetic-skin-samples-for-potential-treatment-of-gout-using-the-metal-assisted-and-microwave-accelerated-decrystallization-technique
#4
Salih Toker, Zainab Boone-Kukoyi, Nishone Thompson, Hillary Ajifa, Travis Clement, Birol Ozturk, Kadir Aslan
Physical stability of synthetic skin samples during their exposure to microwave heating was investigated to demonstrate the use of the metal-assisted and microwave-accelerated decrystallization (MAMAD) technique for potential biomedical applications. In this regard, optical microscopy and temperature measurements were employed for the qualitative and quantitative assessment of damage to synthetic skin samples during 20 s intermittent microwave heating using a monomode microwave source (at 8 GHz, 2-20 W) up to 120 s...
November 30, 2016: ACS Omega
https://www.readbyqxmd.com/read/27913498/long-term-risk-of-second-malignancy-and-cardiovascular-disease-after-hodgkin-lymphoma-treatment
#5
Flora E van Leeuwen, Andrea K Ng
Long-term survivors of Hodgkin lymphoma (HL) experience several late adverse effects of treatment, with second malignant neoplasms (SMNs) and cardiovascular diseases (CVDs) being the leading causes of death in these patients. Other late effects have also been identified, such as pulmonary dysfunction, endocrinopathies (thyroid dysfunction, infertility), neck muscle atrophy, and persistent fatigue. HL survivors have two- to fourfold increased risks to develop SMNs and CVD compared with the general population...
December 2, 2016: Hematology—the Education Program of the American Society of Hematology
https://www.readbyqxmd.com/read/27911127/immediate-and-lasting-effects-of-a-thoracic-spine-manipulation-in-a-patient-with-signs-of-cervical-radiculopathy-and-upper-extremity-hyperalgesia-a-case-report
#6
Beth K Deschenes, Jason Zafereo
Patients with cervical radiculopathy (CR) may present with accompanying symptoms of hyperalgesia, allodynia, heaviness in the arm, and non-segmental pain that do not appear to be related to a peripheral spinal nerve. These findings may suggest the presence of central or autonomic nervous system involvement, requiring a modified management approach. The purpose of this case report is to describe the treatment of a patient with signs of CR and upper extremity (UE) hyperalgesia who had a significant decrease in her UE pain and hypersensitivity after a single thoracic spine manipulation (TSM)...
December 2, 2016: Physiotherapy Theory and Practice
https://www.readbyqxmd.com/read/27910956/spin-crossover-materials-towards-microwave-radiation-switches
#7
Olesia I Kucheriv, Viktor V Oliynyk, Volodymyr V Zagorodnii, Vilen L Launets, Il'ya A Gural'skiy
Microwave electromagnetic radiation that ranges from one meter to one millimetre wavelengths is finding numerous applications for wireless communication, navigation and detection, which makes materials able to tune microwave radiation getting widespread interest. Here we offer a new way to tune GHz frequency radiation by using spin-crossover complexes that are known to change their various physical properties under the influence of diverse external stimuli. As a result of electronic re-configuration process, microwave absorption properties differ for high spin and low spin forms of the complex...
December 2, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27910853/holographic-free-electron-light-source
#8
Guanhai Li, Brendan P Clarke, Jin-Kyu So, Kevin F MacDonald, Nikolay I Zheludev
Recent advances in the physics and technology of light generation via free-electron proximity and impact interactions with nanostructures (gratings, photonic crystals, nano-undulators, metamaterials and antenna arrays) have enabled the development of nanoscale-resolution techniques for such applications as mapping plasmons, studying nanoparticle structural transformations and characterizing luminescent materials (including time-resolved measurements). Here, we introduce a universal approach allowing generation of light with prescribed wavelength, direction, divergence and topological charge via point-excitation of holographic plasmonic metasurfaces...
December 2, 2016: Nature Communications
https://www.readbyqxmd.com/read/27910498/using-visar-to-assess-the-m-band-isotropy-in-hohlraums
#9
N E Lanier, J L Kline, J Morton
In laser based radiation flow experiments, drive variability can often overwhelm the physics sensitivity that one seeks to quantify. Hohlraums can help by providing a more symmetrized, Planckian-like source. However, at higher temperatures, the hohlraum's actual emission can deviate significantly from a truly blackbody, Lambertian source. At the National Ignition Facility (NIF), Dante provides the best quantification of hohlraum output. Unfortunately, limited diagnostic access coupled with NIF's natural symmetry does not allow for Dante measurements at more than two angles...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910410/absolute-calibration-of-the-omega-streaked-optical-pyrometer-for-temperature-measurements-of-compressed-materials
#10
M C Gregor, R Boni, A Sorce, J Kendrick, C A McCoy, D N Polsin, T R Boehly, P M Celliers, G W Collins, D E Fratanduono, J H Eggert, M Millot
Experiments in high-energy-density physics often use optical pyrometry to determine temperatures of dynamically compressed materials. In combination with simultaneous shock-velocity and optical-reflectivity measurements using velocity interferometry, these experiments provide accurate equation-of-state data at extreme pressures (P > 1 Mbar) and temperatures (T > 0.5 eV). This paper reports on the absolute calibration of the streaked optical pyrometer (SOP) at the Omega Laser Facility. The wavelength-dependent system response was determined by measuring the optical emission from a National Institute of Standards and Technology-traceable tungsten-filament lamp through various narrowband (40-nm-wide) filters...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910389/overview-of-diagnostic-performance-and-results-for-the-first-operation-phase-in-wendelstein-7-x-invited
#11
M Krychowiak, A Adnan, A Alonso, T Andreeva, J Baldzuhn, T Barbui, M Beurskens, W Biel, C Biedermann, B D Blackwell, H S Bosch, S Bozhenkov, R Brakel, T Bräuer, B Brotas de Carvalho, R Burhenn, B Buttenschön, A Cappa, G Cseh, A Czarnecka, A Dinklage, P Drews, A Dzikowicka, F Effenberg, M Endler, V Erckmann, T Estrada, O Ford, T Fornal, H Frerichs, G Fuchert, J Geiger, O Grulke, J H Harris, H J Hartfuß, D Hartmann, D Hathiramani, M Hirsch, U Höfel, S Jabłoński, M W Jakubowski, J Kaczmarczyk, T Klinger, S Klose, J Knauer, G Kocsis, R König, P Kornejew, A Krämer-Flecken, N Krawczyk, T Kremeyer, I Książek, M Kubkowska, A Langenberg, H P Laqua, M Laux, S Lazerson, Y Liang, S C Liu, A Lorenz, A O Marchuk, S Marsen, V Moncada, D Naujoks, H Neilson, O Neubauer, U Neuner, H Niemann, J W Oosterbeek, M Otte, N Pablant, E Pasch, T Sunn Pedersen, F Pisano, K Rahbarnia, L Ryć, O Schmitz, S Schmuck, W Schneider, T Schröder, H Schuhmacher, B Schweer, B Standley, T Stange, L Stephey, J Svensson, T Szabolics, T Szepesi, H Thomsen, J-M Travere, H Trimino Mora, H Tsuchiya, G M Weir, U Wenzel, A Werner, B Wiegel, T Windisch, R Wolf, G A Wurden, D Zhang, A Zimbal, S Zoletnik
Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered a MARFE-like radiation zone on the inboard side of machine module 4...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910339/atomic-physics-modeling-of-transmission-spectra-of-sc-doped-aerogel-foams-to-support-omega-experiments
#12
H M Johns, N E Lanier, J L Kline, C J Fontes, T S Perry, C L Fryer, C R D Brown, J W Morton, J D Hager, M E Sherrill
We present synthetic transmission spectra generated with PrismSPECT utilizing both the ATBASE model and the Los Alamos opacity library (OPLIB) to evaluate whether an alternative choice in atomic data will impact modeling of experimental data from radiation transport experiments using Sc-doped aerogel foams (ScSi6O12 at 75 mg/cm(3) density). We have determined that in the 50-200 eV Te range there is a significant difference in the 1s-3p spectra, especially below 100 eV, and for Te = 200 eV above 5000 eV in photon energy...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910328/measurement-of-deuterium-density-profiles-in-the-h-mode-steep-gradient-region-using-charge-exchange-recombination-spectroscopy-on-diii-d
#13
S R Haskey, B A Grierson, K H Burrell, C Chrystal, R J Groebner, D H Kaplan, N A Pablant, L Stagner
Recent completion of a thirty two channel main-ion (deuterium) charge exchange recombination spectroscopy (CER) diagnostic on the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] enables detailed comparisons between impurity and main-ion temperature, density, and toroidal rotation. In a H-mode DIII-D discharge, these new measurement capabilities are used to provide the deuterium density profile, demonstrate the importance of profile alignment between Thomson scattering and CER diagnostics, and aid in determining the electron temperature at the separatrix...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910318/physics-design-of-the-in-vessel-collection-optics-for-the-iter-electron-cyclotron-emission-diagnostic
#14
W L Rowan, S Houshmandyar, P E Phillips, M E Austin, J H Beno, A E Hubbard, A Khodak, A Ouroua, G Taylor
Measurement of the electron cyclotron emission (ECE) is one of the primary diagnostics for electron temperature in ITER. In-vessel, in-vacuum, and quasi-optical antennas capture sufficient ECE to achieve large signal to noise with microsecond temporal resolution and high spatial resolution while maintaining polarization fidelity. Two similar systems are required. One views the plasma radially. The other is an oblique view. Both views can be used to measure the electron temperature, while the oblique is also sensitive to non-thermal distortion in the bulk electron distribution...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27908146/energy-deposition-clustering-as-a-functional-radiation-quality-descriptor-for-modeling-relative-biological-effectiveness
#15
Fernanda Villegas, Gloria Bäckström, Nina Tilly, Anders Ahnesjö
PURPOSE: To explore the use of the frequency of the energy deposition (ED) clusters of different sizes (cluster order, CO) as a surrogate (instead of, e.g., LET) classification of the physical characteristics of ionizing radiation at a nanometer scale, to construct a framework for the calculation of relative biological effectiveness (RBE) with cell survival as endpoint. METHODS: The frequency of cluster order fCO is calculated by sorting the ED sites generated with the Monte Carlo track structure code LIonTrack into clusters based on a single parameter called the cluster distance dC being the maximum allowed distance between two neighboring EDs belonging to a cluster...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27906790/the-health-physics-society-an-affiliate-of-the-international-radiation-protection-association-irpa
#16
(no author information available yet)
No abstract text is available yet for this article.
January 2017: Health Physics
https://www.readbyqxmd.com/read/27906786/an-underappreciated-radiation-hazard-from-high-voltage-electrodes-in-vacuum
#17
Adam D West, Zack Lasner, David DeMille, Elizabeth P West, Cristian D Panda, John M Doyle, Gerald Gabrielse, Adam Kryskow, Corinne Mitchell
The use of high voltage (HV) electrodes in vacuum is commonplace in physics laboratories. In such systems, it has long been known that electron emission from an HV cathode can lead to bremsstrahlung x rays; indeed, this is the basic principle behind the operation of standard x-ray sources. However, in laboratory setups where x-ray production is not the goal and no electron source is deliberately introduced, field-emitted electrons accelerated by HV can produce x rays as an unintended hazardous byproduct. Both the level of hazard and the safe operating regimes for HV vacuum electrode systems are not widely appreciated, at least in university laboratories...
January 2017: Health Physics
https://www.readbyqxmd.com/read/27905521/evaluation-of-a-silicon-90-sr-betavoltaic-power-source
#18
Jefferson Dixon, Aravindh Rajan, Steven Bohlemann, Dusan Coso, Ajay D Upadhyaya, Ajeet Rohatgi, Steven Chu, Arun Majumdar, Shannon Yee
Betavoltaic energy converters (i.e., β-batteries) are attractive power sources because of their potential for high energy densities (>200 MWh/kg) and long duration continuous discharge (>1 year). However, conversion efficiencies have been historically low (<3%). High efficiency devices can be achieved by matching β-radiation transport length scales with the device physics length scales. In this work, the efficiency of c-Si devices using high-energy (>1 MeV) electrons emitted from (90)Sr as a power source is investigated...
December 1, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27904246/noninvasive-imaging-of-the-biliary-system-relevant-to-percutaneous-interventions
#19
REVIEW
Stephen Thomas, Kayleen Jahangir
Clinical data such as history, physical examination, and laboratory tests are useful in identifying patients with biliary obstruction and biliary sources of infection. However, if intervention is planned, noninvasive imaging is needed to confirm the presence, location, and extent of the disease process. Currently, the most commonly available and used noninvasive modalities are ultrasound (US), computed tomography (CT), magnetic resonance (MR), and nuclear medicine hepatobiliary scintigraphy (HIDA). US is quick, portable, readily available, and is commonly the first imaging modality used when biliary pathology is suspected...
December 2016: Seminars in Interventional Radiology
https://www.readbyqxmd.com/read/27903195/dosimetric-effects-of-onyx-embolization-on-gamma-knife-arteriovenous-malformation-dose-distributions
#20
David J Schlesinger, Håkan Nordström, Anders Lundin, Zhiyuan Xu, Jason P Sheehan
OBJECTIVE Patients with arteriovenous malformations (AVMs) treated with Gamma Knife radiosurgery (GKRS) subsequent to embolization suffer from elevated local failure rates and differences in adverse radiation effects. Onyx is a common embolic material for AVMs. Onyx is formulated with tantalum, a high atomic number (Z = 73) element that has been investigated as a source of dosimetric uncertainty contributing to the less favorable clinical results. However, prior studies have not modeled the complicated anatomical and beam geometries characteristic of GKRS...
December 2016: Journal of Neurosurgery
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