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https://www.readbyqxmd.com/read/28092777/controlling-the-3d-architecture-of-self-lifting-auto-generated-tissue-equivalents-slates-for-optimized-corneal-graft-composition-and-stability
#1
Ricardo M Gouveia, Elena González-Andrades, Juan C Cardona, Carmen González-Gallardo, Ana M Ionescu, Ingrid Garzon, Miguel Alaminos, Miguel González-Andrades, Che J Connon
Ideally, biomaterials designed to play specific physical and physiological roles in vivo should comprise components and microarchitectures analogous to those of the native tissues they intend to replace. For that, implantable biomaterials need to be carefully designed to have the correct structural and compositional properties, which consequently impart their bio-function. In this study, we showed that the control of such properties can be defined from the bottom-up, using smart surface templates to modulate the structure, composition, and bio-mechanics of human transplantable tissues...
December 23, 2016: Biomaterials
https://www.readbyqxmd.com/read/28089381/pet-ct-underlying-physics-instrumentation-and-advances
#2
I Torres Espallardo
Since it was first introduced, the main goal of PET/CT has been to provide both PET and CT images with high clinical quality and to present them to radiologists and specialists in nuclear medicine as a fused, perfectly aligned image. The use of fused PET and CT images quickly became routine in clinical practice, showing the great potential of these hybrid scanners. Thanks to this success, manufacturers have gone beyond considering CT as a mere attenuation corrector for PET, concentrating instead on design high performance PET and CT scanners with more interesting features...
January 12, 2017: Radiología
https://www.readbyqxmd.com/read/28078631/investigation-of-solvent-effects-on-photophysical-properties-of-new-aminophthalimide-derivatives-based-on-methanesulfonate
#3
Ayse Tan, Ebru Bozkurt, Yunus Kara
Novel aminophthalimide derivatives were synthesized starting from (3aR,7aS)-2-(2-hydroxypropyl)-3a,4,7,7a-tetrahydro-1H-isoindole-1,3(2H)-dione (9) , and solvent effects on the photo-physical properties of these newly synthesized aminophthalimide derivatives (compounds 14 and 15) were investigated using UV-Vis absorption spectroscopy, steady-state and time-resolved fluorescence measurements. Both absorption and fluorescence spectra exhibited bathochromic shift with the increased polarity of the solvents for both molecules...
January 11, 2017: Journal of Fluorescence
https://www.readbyqxmd.com/read/28077808/rupture-waves-and-earthquakes
#4
Koji Uenishi
Normally, an earthquake is considered as a phenomenon of wave energy radiation by rupture (fracture) of solid Earth. However, the physics of dynamic process around seismic sources, which may play a crucial role in the occurrence of earthquakes and generation of strong waves, has not been fully understood yet. Instead, much of former investigation in seismology evaluated earthquake characteristics in terms of kinematics that does not directly treat such dynamic aspects and usually excludes the influence of high-frequency wave components over 1 Hz...
2017: Proceedings of the Japan Academy. Series B, Physical and Biological Sciences
https://www.readbyqxmd.com/read/28073539/physical-processes-leading-to-the-development-of-an-anomalously-large-cochlodinium-polykrikoides-bloom-in-the-east-sea-japan-sea
#5
Dae-Won Kim, Young-Heon Jo, Jong-Kuk Choi, Jang-Geun Choi, Hongsheng Bi
An anomalously large Harmful Algal Bloom (HAB) was observed in the southwest coast of the East/Japan Sea (hereafter the East Sea) during the summer of 2013. During this time period, the presence of Cochlodinium polykrikoides (C. polykrikoides) was detected by the Geostationary Ocean Color Imager (GOCI) and validated by in-situ observations. GOCI observations have been available since 2011, thus allowingto examine various stages of the physical condition of the developing C. polykrikoides bloom, thereby other multi-satellite and buoy measurements obtained between 2011 and 2013...
May 2016: Harmful Algae
https://www.readbyqxmd.com/read/28072575/systematics-of-relative-biological-effectiveness-measurements-for-proton-radiation-along-the-spread-out-bragg-peak-experimental-validation-of-the-local-effect-model
#6
Rebecca Grün, Thomas Friedrich, Michael Krämer, Michael Scholz
The purpose of this study is to compare the predictions of the local effect model (LEM) in an extensive analysis to proton relative biological effectiveness (RBE) experiments found in the literature, and demonstrate the capabilities of the model as well as to discuss potential limitations. 19 publications with in vitro experiments and 10 publications with in vivo experiments focusing on proton RBE along the spread out Bragg peak (SOBP) were considered. In total the RBE values of over 100 depth positions were compared to LEM predictions...
February 7, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28069937/centuries-of-thermal-sea-level-rise-due-to-anthropogenic-emissions-of-short-lived-greenhouse-gases
#7
Kirsten Zickfeld, Susan Solomon, Daniel M Gilford
Mitigation of anthropogenic greenhouse gases with short lifetimes (order of a year to decades) can contribute to limiting warming, but less attention has been paid to their impacts on longer-term sea-level rise. We show that short-lived greenhouse gases contribute to sea-level rise through thermal expansion (TSLR) over much longer time scales than their atmospheric lifetimes. For example, at least half of the TSLR due to increases in methane is expected to remain present for more than 200 y, even if anthropogenic emissions cease altogether, despite the 10-y atmospheric lifetime of this gas...
January 9, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28069070/successful-management-of-synchronous-recurrent-breast-carcinoma-with-chronic-myelogenous-leukemia-a-case-report
#8
Choukri Elm'hadi, Mohamed Reda Khmamouche, Rachid Tanz, Mehdi Toreis, ElMehdi Mahtat, Mohammed Allaoui, Mohammed Oukabli, Nezha Messaoudi, Hassan Errihani, Mohammed Ichou
BACKGROUND: Survival is increasing after early breast cancer revealing frequent relapses and possibility of developing secondary malignancies. The concomitant occurrence of these two events is exceptionally disastrous and lethal. We report a case of a Moroccan woman who was successfully managed for synchronous recurrent breast carcinoma and chronic myelogenous leukemia. CASE PRESENTATION: A 42-year-old Moroccan woman was diagnosed with localized breast carcinoma in 2008...
January 10, 2017: Journal of Medical Case Reports
https://www.readbyqxmd.com/read/28068518/impact-of-space-environment-on-stability-of-medicines-challenges-and-prospects
#9
REVIEW
Priti Mehta, Dhara Bhayani
To upkeep health of astronauts in a unique, isolated, and extreme environment of space is the primary goal for a successful space mission, hence, safe and efficacious medications are essential for the wellness of astronauts. Space medication has been challenged with problems related to efficacy. Along with altered physiology, one of the possible reasons could be instability of space medications in the presence of harsh spaceflight environmental conditions. Altered physical and chemical stability can result in reduced potency which can result in reduced efficacy...
January 3, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28068248/clinical-implementation-of-dual-energy-ct-for-proton-treatment-planning-on-pseudo-monoenergetic-ct-scans
#10
Patrick Wohlfahrt, Christian Möhler, Volker Hietschold, Stefan Menkel, Steffen Greilich, Mechthild Krause, Michael Baumann, Wolfgang Enghardt, Christian Richter
PURPOSE: To determine whether a standardized clinical application of dual-energy computed tomography (DECT) for proton treatment planning based on pseudomonoenergetic CT scans (MonoCTs) is feasible and increases the precision of proton therapy in comparison with single-energy CT (SECT). METHODS AND MATERIALS: To define an optimized DECT protocol, CT scan settings were analyzed experimentally concerning beam hardening, image quality, and influence on the heuristic conversion of CT numbers into stopping-power ratios (SPRs) and were compared with SECT scans with identical CT dose...
February 1, 2017: International Journal of Radiation Oncology, Biology, Physics
https://www.readbyqxmd.com/read/28060696/acute-pancreatitis-and-posterior-reversible-encephalopathy-syndrome-a-case-report
#11
Vítor Magno Pereira, Luís Marote Correia, Tiago Rodrigues, Gorete Serrão Faria
The posterior reversible encephalopathy syndrome is a neurological syndrome characterized by headache, confusion, visual disturbances and seizures associated with identifiable areas of cerebral edema on imaging studies. The authors report the case of a man, 33 years-old, leukodermic with a history of chronic alcohol and tobacco consumption, who is admitted to the emergency department for epigastric pain radiating to the back and vomiting with about six hours of evolution and an intense holocranial headache for two hours...
September 2016: Acta Médica Portuguesa
https://www.readbyqxmd.com/read/28060412/optimizing-dual-energy-x-ray-parameters-for-the-exactrac-clinical-stereoscopic-imaging-system-to-enhance-soft-tissue-imaging
#12
Wesley A Bowman, James L Robar, Mike Sattarivand
PURPOSE: Stereoscopic x-ray image guided radiotherapy for lung tumors is often hindered by bone overlap and limited soft tissue contrast. This study aims to evaluate the feasibility of dual-energy imaging techniques and to optimize parameters of the ExacTrac stereoscopic imaging system to enhance soft tissue imaging for application to lung stereotactic body radiation therapy. METHODS: Simulated spectra and a physical lung phantom were used to optimize filter material, thickness, tube potentials, and weighting factors to obtain bone subtracted dual-energy images...
January 6, 2017: Medical Physics
https://www.readbyqxmd.com/read/28060036/daily-weather-and-children-s-physical-activity-patterns
#13
Teun Remmers, Carel Thijs, Anna Timperio, Jo Salmon, Jenny Veitch, Stef P J Kremers, Nicola D Ridgers
INTRODUCTION: Understanding how the weather affects physical activity (PA) may help in the design, analysis and interpretation of future studies, especially when investigating PA across diverse meteorological settings and with long follow-up periods. The present longitudinal study first aims to examine the influence of daily weather elements on intra-individual PA patterns among primary school children across four seasons, reflecting day-to-day variation within each season. Second, we investigate whether the influence of weather elements differs by day of the week (weekdays vs...
January 3, 2017: Medicine and Science in Sports and Exercise
https://www.readbyqxmd.com/read/28052509/spatially-dependent-biotic-and-abiotic-factors-drive-survivorship-and-physical-structure-of-green-roof-vegetation
#14
Jason M Aloisio, Matthew I Palmer, Mario A Giampieri, Amy R Tuininga, James D Lewis
Plant survivorship depends on biotic and abiotic factors that vary at local and regional scales. This survivorship, in turn, has cascading effects on community composition and the physical structure of vegetation. Survivorship of native plant species is variable among populations planted in environmentally stressful habitats like urban roofs, but the degree to which factors at different spatial scales affect survivorship in urban systems is not well understood. We evaluated the effects of biotic and abiotic factors on survivorship, composition, and physical structure of two native perennial species assemblages, one characterized by a mixture of C4 grasses and forbs (Hempstead Plains, HP) and one characterized by a mixture of C3 grasses and forbs (Rocky Summit, RS), that were initially sown at equal ratios of growth forms (5:1:4; grass, N-fixing forb and non-N-fixing forb) in replicate 2-m(2) plots planted on 10 roofs in New York City (New York, USA)...
January 2017: Ecological Applications: a Publication of the Ecological Society of America
https://www.readbyqxmd.com/read/28048918/su-f-r-11-designing-quality-and-safety-informatics-through-implementation-of-a-ct-radiation-dose-monitoring-program
#15
J M Wilson, E Samei
PURPOSE: Recent legislative and accreditation requirements have driven rapid development and implementation of CT radiation dose monitoring solutions. Institutions must determine how to improve quality, safety, and consistency of their clinical performance. The purpose of this work was to design a strategy and meaningful characterization of results from an in-house, clinically-deployed dose monitoring solution. METHODS: A dose monitoring platform was designed by our imaging physics group that focused on extracting protocol parameters, dose metrics, and patient demographics and size...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048903/su-f-e-17-a-dedicated-teaching-and-research-linac-as-a-stepping-stone-to-introduce-medical-physics-to-students
#16
L Beaulieu, L Gingras, M Bergeron, L Archambault
PURPOSE: This work describes how a non-clinical, research and teaching Linac is used as an extremely motivating and exciting way to introduce students to medical physics. METHODS: The dedicated facility was inaugurated in 2014. The facility is composed of a fully equipped and functional state-of-the-art Varian TrueBeam Linac and a complete set of physics instruments and QA phantoms for the Linac and onboard imaging. The Linac bunker and treatment console are oversized such that a class of 12-15 can comfortably fit, seated if needed for longer sessions...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048902/we-g-brc-00-experiences-with-tg100-in-clinical-use
#17
Grace Gwe-Ya Kim
: Failure Mode and Effects Analysis (FMEA) originated as an industrial engineering technique used for risk management and safety improvement of complex processes. In the context of radiotherapy, the AAPM Task Group 100 advocates FMEA as the framework of choice for establishing clinical quality management protocols. However, there is concern that widespread adoption of FMEA in radiation oncology will be hampered by the perception that implementation of the tool will have a steep learning curve, be extremely time consuming and labor intensive, and require additional resources...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048898/mo-fg-brc-03-design-and-construction-of-a-dielectiric-wall-accelerator
#18
D Westerly
Experimental research in medical physics has expanded the limits of our knowledge and provided novel imaging and therapy technologies for patients around the world. However, experimental efforts are challenging due to constraints in funding, space, time and other forms of institutional support. In this joint ESTRO-AAPM symposium, four exciting experimental projects from four different countries are highlighted. Each project is focused on a different aspect of radiation therapy. From the USA, we will hear about a new linear accelerator concept for more compact and efficient therapy devices...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048892/su-f-j-116-clinical-experience-based-verification-and-improvement-of-a-4dct-program
#19
P Fogg, M West, T Aland
PURPOSE: To demonstrate the role of continuous improvement fulfilled by the Medical Physicist in clinical 4DCT and CBCT scanning. METHODS: Lung (SABR and Standard) patients' 4D respiratory motion and image data were reviewed over a 3, 6 and 12 month period following commissioning testing. By identifying trends of clinically relevant parameters and respiratory motions, variables were tested with a programmable motion phantom and assessed. Patient traces were imported to a motion phantom and 4DCT and CBCT imaging were performed...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048884/th-ef-204-02-small-field-radiation-therapy-physics-and-recent-recommendations-from-iaea-and-icru
#20
J Seuntjens
: Joanna E. Cygler, Jan Seuntjens, J. Daniel Bourland, M. Saiful Huq, Josep Puxeu Vaque, Daniel Zucca Aparicio, Tatiana Krylova, Yuri Kirpichev, Eric Ford, Caridad Borras Stereotactic Radiation Therapy (SRT) utilizes small static and dynamic (IMRT) fields, to successfully treat malignant and benign diseases using techniques such as Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT). SRT is characterized by sharp dose gradients for individual fields and their resultant dose distributions...
June 2016: Medical Physics
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