keyword
MENU ▼
Read by QxMD icon Read
search

Radiation dose measurements

keyword
https://www.readbyqxmd.com/read/28214891/up-regulated-atf4-expression-increases-cell-sensitivity-to-apoptosis-in-response-to-radiation
#1
Ying Zong, Shijie Feng, Jinwei Cheng, Chenlin Yu, Guocai Lu
BACKGROUND/AIMS: Activating transcription factor 4 (ATF4) is a member of the activating transcription factor family which regulates the expression of genes involved in amino acid metabolism, redox homeostasis and ER stress responses. ATF4 is also over-expressed in human solid tumors, although its effect on responsiveness to radiation is largely unexplored. METHODS: Real-time PCR was used to detect ATF4 mRNA levels in cells treated with different doses of 60Coγ radiation...
February 13, 2017: Cellular Physiology and Biochemistry
https://www.readbyqxmd.com/read/28213023/inactivation-of-escherichia-coli-o157-h7-salmonella-typhimurium-and-listeria-monocytogenes-in-ready-to-bake-cookie-dough-by-gamma-and-electron-beam-irradiation
#2
Seul-Gi Jeong, Dong-Hyun Kang
This study was conducted to investigate the efficacy of gamma and electron beam irradiation to inactivate foodborne pathogens in ready-to-bake cookie dough and to determine the effect on quality by measuring color and texture changes. Cookie dough inoculated with Escherichia coli O157:H7, Salmonella Typhimurium, or Listeria monocytogenes was subjected to gamma and electron beam irradiation, with doses ranging from 0 to 3 kGy. As the radiation dose increased, the inactivation effect increased among all tested pathogens...
June 2017: Food Microbiology
https://www.readbyqxmd.com/read/28212705/detection-of-dna-damage-by-space-radiation-in-human-fibroblasts-flown-on-the-international-space-station
#3
Tao Lu, Ye Zhang, Michael Wong, Alan Feiveson, Ramona Gaza, Nicholas Stoffle, Huichen Wang, Bobby Wilson, Larry Rohde, Louis Stodieck, Fathi Karouia, Honglu Wu
Although charged particles in space have been detected with radiation detectors on board spacecraft since the discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation is challenging due to the low dose and low dose rate nature of the radiation environment, and due to the difficulty in distinguishing the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in their lymphocytes and early onset of cataracts, are attributed primarily to their exposure to space radiation...
February 2017: Life Sciences in Space Research
https://www.readbyqxmd.com/read/28212704/neurochemical-differences-in-learning-and-memory-paradigms-among-rats-supplemented-with-anthocyanin-rich-blueberry-diets-and-exposed-to-acute-doses-of-56-fe-particles
#4
Shibu M Poulose, Bernard M Rabin, Donna F Bielinski, Megan E Kelly, Marshall G Miller, Nopporn Thanthaeng, Barbara Shukitt-Hale
The protective effects of anthocyanin-rich blueberries (BB) on brain health are well documented and are particularly important under conditions of high oxidative stress, which can lead to "accelerated aging." One such scenario is exposure to space radiation, consisting of high-energy and -charge particles (HZE), which are known to cause cognitive dysfunction and deleterious neurochemical alterations. We recently tested the behavioral and neurochemical effects of acute exposure to HZE particles such as (56)Fe, within 24-48h after exposure, and found that radiation primarily affects memory and not learning...
February 2017: Life Sciences in Space Research
https://www.readbyqxmd.com/read/28212111/direct-determination-of-k-q-for-farmer-type-ionization-chambers-in-a-clinical-scanned-carbon-ion-beam-using-water-calorimetry
#5
J-M Osinga-Blättermann, S Brons, S Greilich, O Jäkel, A Krauss
Until now, the dosimetry of carbon ions with ionization chambers has not reached the same level of accuracy as that of high-energy photons. This is mainly caused by the approximately threefold larger uncertainty of the k Q factor of ionization chambers, which, due to the lack of experimental data, is still derived by calculations. Measurements of absorbed dose to water, D w, by means of water calorimetry have now been performed in the entrance channel of a scanned 6 cm  ×  6 cm radiation field of 429 MeV/u carbon ions, allowing the direct calibration of ionization chambers and thus the experimental determination of k Q...
February 17, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28212051/-99m-tc-mag3-image-wisely
#6
Andrew T Taylor, Russell D Folks, A K M Fazlur Rahman, Aruna Polsani, Eva V Dubovsky, Raghuveer Halkar, Amita Manatunga
Purpose To determine if commonly administered doses of technetium 99m ((99m)Tc) mertiatide (MAG3) in the range of 300-370 MBq (approximately 8-10 mCi) contribute to image interpretation and justify the resulting radiation exposure. Materials and Methods The respective institutional review boards approved this HIPAA-compliant study and waived informed consent. Baseline and furosemide (99m)Tc-MAG3 imaging examinations in 50 patients suspected of having renal obstruction and 48 patients suspected of having renovascular hypertension (RVH) were randomly selected from archived databases and were independently scored by three experienced readers without access to 2-second flow images...
February 17, 2017: Radiology
https://www.readbyqxmd.com/read/28212000/radiation-hard-complementary-integrated-circuits-based-on-semiconducting-single-walled-carbon-nanotubes
#7
Julian J McMorrow, Cory D Cress, William A Gaviria Rojas, Michael L Geier, Tobin J Marks, Mark C Hersam
Increasingly complex demonstrations of integrated circuit elements based on semiconducting single-walled carbon nanotubes (SWCNTs) mark the maturation of this technology for use in next-generation electronics. In particular, organic materials have recently been leveraged as dopant and encapsulation layers to enable stable SWCNT-based rail-to-rail, low-power complementary metal-oxide-semiconductor (CMOS) logic circuits. To explore the limits of this technology in extreme environments, here we study total ionizing dose (TID) effects in enhancement-mode SWCNT-CMOS inverters that employ organic doping and encapsulation layers...
February 17, 2017: ACS Nano
https://www.readbyqxmd.com/read/28211638/the-relationship-between-ovarian-function-and-ovarian-limited-dose-in-radiotherapy-postoperation-of-ovarian-transposition-in-young-patients-with-cervical-cancer
#8
Zhenhua Du, Hui Qu
In this study, the relationship between ovarian function and ovarian limited dose in radiotherapy was evaluated in young patients with cervical cancer who underwent ovarian transposition (Fig1B). Moreover, the novel ovarian dose limit for a better preservation of ovarian function in intensity-modulated radiation therapy (IMRT) was determined. We retrospectively analyzed data from 86 patients with cervical cancer who received radical hysterectomy and ovarian transposition from January 2013 to June 2015. In agreement with the National Comprehensive Cancer Network Guidelines (NCCN) for Cervical Cancer Version 2...
February 17, 2017: Cancer Medicine
https://www.readbyqxmd.com/read/28209907/equivalent-dose-rate-at-1m-of-patients-with-known-or-suspected-neuroendocrine-tumor-exiting-a-nuclear-medicine-department-after-68-ga-dotatoc-18-f-fdopa-or-18-f-fdg-pet-ct-or-111-in-pentetreotide-or-123-i-mibg-spect-ct
#9
Jules Zhang-Yin, Anne-Sophie Dirand, Myriam Sasanelli, Gwenaelle Corrégé, Aude Peudon, Thierry Kiffel, Valérie Nataf, Jérôme Clerc, Françoise Montravers, Jean-Noël Talbot
(123)I-mIBG and (111)In-pentetrotide SPECT have been used for functional imaging of neuroendocrine tumors (NET) for the last two decades. More recently, PET/CT imaging with (18)F-FDG, (18)F-FDOPA and (68)Ga somatostatin-receptor ligands in NETs has been expanding. No direct measurements of the dose rate from NET patients exiting the nuclear medicine department could be found in the literature after PET/CT with (18)F-FDOPA or (68)Ga-DOTATOC, a somatostatin analogue. Methods: We measured the dose rates from NET patients undergoing PET/CT or SPECT/CT in our centers...
February 16, 2017: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
https://www.readbyqxmd.com/read/28209443/continued-benefit-to-rectal-separation-for-prostate-radiation-therapy-final-results-of%C3%A2-a%C3%A2-phase-iii-trial
#10
Daniel A Hamstra, Neil Mariados, John Sylvester, Dhiren Shah, Lawrence Karsh, Richard Hudes, David Beyer, Steven Kurtzman, Jeffrey Bogart, R Alex Hsi, Michael Kos, Rodney Ellis, Mark Logsdon, Shawn Zimberg, Kevin Forsythe, Hong Zhang, Edward Soffen, Patrick Francke, Constantine Mantz, Peter Rossi, Theodore DeWeese, Stephanie Daignault-Newton, Benjamin W Fischer-Valuck, Anupama Chundury, Hiram Gay, Walter Bosch, Jeff Michalski
PURPOSE: SpaceOAR, a Food and Drug Administration-approved hydrogel intended to create a rectal-prostate space, was evaluated in a single-blind phase III trial of image guided intensity modulated radiation therapy. A total of 222 men were randomized 2:1 to the spacer or control group and received 79.2 Gy in 1.8-Gy fractions to the prostate with or without the seminal vesicles. The present study reports the final results with a median follow-up period of 3 years. METHODS AND MATERIALS: Cumulative (Common Terminology Criteria for Adverse Events, version 4...
December 23, 2016: International Journal of Radiation Oncology, Biology, Physics
https://www.readbyqxmd.com/read/28206821/simulated-space-radiation-impact-of-four-different-types-of-high-dose-ionizing-radiation-on-the-lichen-xanthoria-elegans
#11
Annette Brandt, Joachim Meeßen, Reiner U Jänicke, Marina Raguse, Sieglinde Ott
This study addresses the viability of the lichen Xanthoria elegans after high-dose ionizing irradiation in the frame of the STARLIFE campaign. The first set of experiments was intended to resemble several types of galactic cosmic radiation (GCR) as present beyond the magnetic shield of Earth. In the second set of experiments, γ radiation up to 113 kGy was applied to test the limit of lichen resistance to ionizing radiation. Entire thalli of Xanthoria elegans were irradiated in the anhydrobiotic state. After STARLIFE 1, the metabolic activity of both symbionts was quantified by live/dead staining with confocal laser scanning microscopy...
February 2017: Astrobiology
https://www.readbyqxmd.com/read/28204857/low-dose-ct-imaging-of-a-total-hip-arthroplasty-phantom-using-model-based-iterative-reconstruction-and-orthopedic-metal-artifact-reduction
#12
R H H Wellenberg, M F Boomsma, J A C van Osch, A Vlassenbroek, J Milles, M A Edens, G J Streekstra, C H Slump, M Maas
OBJECTIVE: To compare quantitative measures of image quality, in terms of CT number accuracy, noise, signal-to-noise-ratios (SNRs), and contrast-to-noise ratios (CNRs), at different dose levels with filtered-back-projection (FBP), iterative reconstruction (IR), and model-based iterative reconstruction (MBIR) alone and in combination with orthopedic metal artifact reduction (O-MAR) in a total hip arthroplasty (THA) phantom. MATERIALS AND METHODS: Scans were acquired from high- to low-dose (CTDIvol: 40...
February 15, 2017: Skeletal Radiology
https://www.readbyqxmd.com/read/28202732/atomic-structure-of-granulin-determined-from-native-nanocrystalline-granulovirus-using-an-x-ray-free-electron-laser
#13
Cornelius Gati, Dominik Oberthuer, Oleksandr Yefanov, Richard D Bunker, Francesco Stellato, Elaine Chiu, Shin-Mei Yeh, Andrew Aquila, Shibom Basu, Richard Bean, Kenneth R Beyerlein, Sabine Botha, Sébastien Boutet, Daniel P DePonte, R Bruce Doak, Raimund Fromme, Lorenzo Galli, Ingo Grotjohann, Daniel R James, Christopher Kupitz, Lukas Lomb, Marc Messerschmidt, Karol Nass, Kimberly Rendek, Robert L Shoeman, Dingjie Wang, Uwe Weierstall, Thomas A White, Garth J Williams, Nadia A Zatsepin, Petra Fromme, John C H Spence, Kenneth N Goldie, Johannes A Jehle, Peter Metcalf, Anton Barty, Henry N Chapman
To understand how molecules function in biological systems, new methods are required to obtain atomic resolution structures from biological material under physiological conditions. Intense femtosecond-duration pulses from X-ray free-electron lasers (XFELs) can outrun most damage processes, vastly increasing the tolerable dose before the specimen is destroyed. This in turn allows structure determination from crystals much smaller and more radiation sensitive than previously considered possible, allowing data collection from room temperature structures and avoiding structural changes due to cooling...
February 15, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28198880/proton-therapy-dosimetry-using-the-scintillation-of-the-silica-fibers
#14
Arash Darafsheh, Reza Taleei, Alireza Kassaee, Jarod C Finlay
We investigate the feasibility of proton therapy dose measurement by using scintillation of a bare silica glass fiber. The emission spectra of the optical fiber at various depths in tissue-mimicking phantoms, irradiated with proton beams of energies 100-225 MeV show two distinct peaks at 460 and 650 nm whose nature is connected with the silica point defects. Our experimental results and Monte Carlo simulation showed that the Čerenkov radiation cannot be responsible for such a phenomenon. We showed that the intensity of the peak at 650 nm correlates with the proton dose with a minimal effect of ionization quenching, while the intensity peak at 460 nm under-reports the radiation dose...
February 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/28198573/radiation-dose-benchmarks-in-pediatric-cardiac-catheterization-a-prospective-multi-center-c3po-qi-study
#15
Priscila C Cevallos, Aimee K Armstrong, Andrew C Glatz, Bryan H Goldstein, Todd M Gudausky, Ryan A Leahy, Christopher J Petit, Shabana Shahanavaz, Sara M Trucco, Lisa J Bergersen
OBJECTIVES: This study sought to update benchmark values to use a quality measure prospectively. BACKGROUND: Congenital Cardiac Catheterization Outcomes Project - Quality Improvement (C3PO-QI), a multi-center registry, defined initial radiation dose benchmarks retrospectively across common interventional procedures. These data facilitated a dose metric endorsed by the American College of Cardiology in 2014. METHODS: Data was collected prospectively by 9 C3PO-QI institutions with complete case capture between 1/1/2014 and 6/30/2015...
February 15, 2017: Catheterization and Cardiovascular Interventions
https://www.readbyqxmd.com/read/28192285/real-time-detection-of-fast-and-thermal-neutrons-in-radiotherapy-with-cmos-sensors
#16
Nicolas Arbor, Stephane Higueret, Halima Elazhar, Rodolphe Combe, Philippe Meyer, Nicolas Dehaynin, Florence Taupin, Daniel Husson
The peripheral dose distribution is a growing concern for the improvement of new external radiation modalities. Secondary particles, especially photo-neutrons produced by the accelerator, irradiate the patient more than tens of centimeters away from the tumor volume. However the out-of-field dose is still not estimated accurately by the treatment planning softwares. This study demonstrates the possibility of using a specially designed CMOS sensor for fast and thermal neutron monitoring in radiotherapy. The 14 microns-thick sensitive layer and the integrated electronic chain of the CMOS are particularly suitable for real-time measurements in γ/n mixed fields...
March 7, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28192281/design-of-a-head-phantom-produced-on-a-3d-rapid-prototyping-printer-and-comparison-with-a-rando-and-3m-lucite-head-phantom-in-eye-dosimetry-applications
#17
Peter Homolka, Michael Figl, Andreas Wartak, Mathias Glanzer, Martina Duenkelmeyer, Azadeh Hojreh, Johann Hummel
An anthropomorphic head phantom including eye inserts allowing placement of TLDs 3 mm below the cornea has been produced on a 3D printer using photo-cured-acrylic resin to best allow tissue equivalence. Thus Hp(3) can be determined in radiological and interventional photon radiation fields. Eye doses and doses to the forehead have been compared to an Alderson RANDO head and a 3M Lucite skull phantom in terms of surface dose per incident air kerma for frontal irradiation since the commercial phantoms do not allow placement of TLDs 3 mm below the corneal surface...
February 13, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28190371/occupational-radiation-exposure-of-anesthesia-providers
#18
Rachel R Wang, Amanda H Kumar, Pedro Tanaka, Alex Macario
Anesthesia providers are frequently exposed to radiation during routine patient care in the operating room and remote anesthetizing locations. Eighty-two percent of anesthesiology residents (n = 57 responders) at our institution had a "high" or "very high" concern about the level of ionizing radiation exposure, and 94% indicated interest in educational materials about radiation safety. This article highlights key learning points related to basic physical principles, effects of ionizing radiation, radiation exposure measurement, occupational dose limits, considerations during pregnancy, sources of exposure, factors affecting occupational exposure such as positioning and shielding, and monitoring...
February 1, 2017: Seminars in Cardiothoracic and Vascular Anesthesia
https://www.readbyqxmd.com/read/28189068/passiflora-tarminiana-fruits-reduce-uvb-induced-photoaging-in-human-skin-fibroblasts
#19
Karent Bravo, Luisa Duque, Federico Ferreres, Diego A Moreno, Edison Osorio
Skin aging is a complex process that is strongly affected by UV radiation, which stimulates the production of reactive oxygen species (ROS) in the epidermis and dermis and subsequently causes skin damage. Among the major consequences are increased collagen degradation and reduced collagen synthesis. Previous reports have demonstrated the beneficial effects of polyphenols for healthy skin. Passiflora tarminiana Coppens & V.E. Barney, a species of the Passifloraceae family, is widely distributed in South America and is rich in flavonoids...
February 3, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28188481/internal-exposure-to-neutron-activated-56-mn-dioxide-powder-in-wistar-rats-part%C3%A2-1-dosimetry
#20
Valeriy Stepanenko, Tolebay Rakhypbekov, Keiko Otani, Satoru Endo, Kenichi Satoh, Noriyuki Kawano, Kazuko Shichijo, Masahiro Nakashima, Toshihiro Takatsuji, Aya Sakaguchi, Hiroaki Kato, Yuichi Onda, Nariaki Fujimoto, Shin Toyoda, Hitoshi Sato, Altay Dyussupov, Nailya Chaizhunusova, Nurlan Sayakenov, Darkhan Uzbekov, Aisulu Saimova, Dariya Shabdarbaeva, Mazhin Skakov, Alexandr Vurim, Vyacheslav Gnyrya, Almas Azimkhanov, Alexander Kolbayenkov, Kasym Zhumadilov, Yankar Kairikhanova, Andrey Kaprin, Vsevolod Galkin, Sergey Ivanov, Timofey Kolyzhenkov, Aleksey Petukhov, Elena Yaskova, Irina Belukha, Artem Khailov, Valeriy Skvortsov, Alexander Ivannikov, Umukusum Akhmedova, Viktoria Bogacheva, Masaharu Hoshi
There were two sources of ionizing irradiation after the atomic bombings of Hiroshima and Nagasaki: (1) initial gamma-neutron irradiation at the moment of detonation and (2) residual radioactivity. Residual radioactivity consisted of two components: radioactive fallout containing fission products, including radioactive fissile materials from nuclear device, and neutron-activated radioisotopes from materials on the ground. The dosimetry systems DS86 and DS02 were mainly devoted to the assessment of initial radiation exposure to neutrons and gamma rays, while only brief considerations were given for the estimation of doses caused by residual radiation exposure...
February 10, 2017: Radiation and Environmental Biophysics
keyword
keyword
6437
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"