Comparison of build-up dose between Elekta and Varian linear accelerators for high-energy photon beams using radiochromic film and clinical implications for IMRT head and neck treatments.

abstract：:The effect of the physical state (phase) of the absorbing medium and the energy straggling of the alpha particles on the calculation of the radiation dose due to the daughter products of radon deposited in the lung have been studied in detail. The stopping power data for alpha particles in water and water vapour have ...

journal_title：Physics in medicine and biology

authors： Haque AK,Al-affan IA

更新日期：1987-08-01 00:00:00

abstract：:The lipid disordering effect of aspirin on the liposomal membrane of dipalmitoyl phosphatidyl choline has recently been studied using the fluorescence polarization method. From the anisotropy-temperature curve, we have calculated here the associated change in van't Hoff enthalpy. Since the fluorescence technique requi...

journal_title：Physics in medicine and biology

authors： De S,Ghosh AK,Basu R,Nandy P

更新日期：1996-03-01 00:00:00

abstract：:In this paper, we investigate an off-line strategy to incorporate inter-fraction organ motion in IMRT treatment planning. It was suggested that inverse planning could be based on a probability distribution of patient geometries instead of a single snap shot. However, this concept is connected to two intrinsic problems...

journal_title：Physics in medicine and biology

authors： Unkelbach J,Oelfke U

更新日期：2004-09-07 00:00:00

abstract：:We propose a novel scintillation detector design for positron emission tomography (PET), which has depth of interaction (DOI) capability and uses a single-ended readout scheme. The DOI detector contains a pair of crystal bars segmented using sub-surface laser engraving (SSLE). The two crystal bars are optically couple...

journal_title：Physics in medicine and biology

authors： Uchida H,Sakai T,Yamauchi H,Hakamata K,Shimizu K,Yamashita T

更新日期：2016-09-21 00:00:00

abstract：:We comment on a recent article (Gomà et al 2014 Phys. Med. Biol. 59 4961-71) which compares different routes of reference dosimetry for the energy dependent beam monitor calibration in scanned proton beams. In this article, a 3% discrepancy is reported between a Faraday cup and a plane-parallel ionization chamber in t...

journal_title：Physics in medicine and biology

authors： Palmans H,Vatnitsky SM

更新日期：2016-09-07 00:00:00

abstract：:The layer-stacking method can provide three-dimensional conformal dose distributions to the target based on a passive scattering method using mini-spread-out Bragg peak (SOBP). The purpose of this work is to demonstrate the effectiveness of a new weight optimization algorithm that can enhance the robustness of dose di...

journal_title：Physics in medicine and biology

authors： Sakamoto Y,Maeda Y,Yamada Y,Ikeda M,Tameshige Y,Sasaki M,Shibata S,Yamamoto K

更新日期：2020-09-28 00:00:00

abstract：:Numerical computations are used to evaluate electric field dosimetry for high-resolution anatomically based inhomogeneous models of a human male child, and male and female rats and mice, under exposure to 60 Hz uniform magnetic field sources of three perpendicular orientations. The goal is to compare the child data to...

journal_title：Physics in medicine and biology

authors： Dawson TW,Caputa K,Stuchly MA

更新日期：2002-07-21 00:00:00

abstract：:Recent image guidance developments for preclinical synchrotron microbeam radiotherapy represent a necessary step for future clinical translation of the technique. Image quality can be further improved using x-ray phase contrast, which is readily available at synchrotron facilities. We here describe a methodology for p...

journal_title：Physics in medicine and biology

authors： Pelliccia D,Crosbie JC,Larkin KG

更新日期：2016-08-21 00:00:00

abstract：:A simple and fast, but sensitive TLD method for the measurement of energy and homogeneity of therapeutically used electron beams has been developed and tested. This method is based on the fact that when small thicknesses of high-Z absorbers such as lead are interposed in the high-energy electron beams, the transmitted...

journal_title：Physics in medicine and biology

authors： Pradhan AS,Quast U,Sharma PK

更新日期：1994-09-01 00:00:00

abstract：:Although radionuclide therapy has been around for a long time, this modality of cancer treatment has been limited mainly to the use of [32P]-phosphate and [131I]-sodium iodide. The last few years, however, have seen an increased interest in this area due to new developments of radionuclides and carrier molecules that ...

journal_title：Physics in medicine and biology

authors： Zweit J

更新日期：1996-10-01 00:00:00

abstract：:Non-invasively reconstructing the cardiac transmembrane potentials (TMPs) from body surface potentials can act as a regression problem. The support vector regression (SVR) method is often used to solve the regression problem, however the computational complexity of the SVR training algorithm is usually intensive. In t...

journal_title：Physics in medicine and biology

authors： Jiang M,Zhang H,Zhu L,Cao L,Wang Y,Xia L,Gong Y

更新日期：2015-04-21 00:00:00

abstract：:DMSA imaging is carried out in nuclear medicine to assess the level of functional renal tissue in patients. This study investigated the use of an artificial neural network to perform diagnostic classification of these scans. Using the radiological report as the gold standard, the network was trained to classify DMSA s...

journal_title：Physics in medicine and biology

authors： Wright JW,Duguid R,McKiddie F,Staff RT

更新日期：2014-04-07 00:00:00

abstract：:Automatic cell cycle analysis (DNA histograms) is usually performed with flow cytometry. In cases when only few cells are available, the DNA content has to be measured with a fluorescence microscope combined with sensitive camera systems (SIT, MCP, cooled CCDs) and a frame grabber for image analysis. The fluorescent c...

journal_title：Physics in medicine and biology

authors： Böcker W,Gantenberg HW,Müller WU,Streffer C

更新日期：1996-03-01 00:00:00

abstract：:Conventional molecular assessment of tissue through histology, if adapted to fresh thicker samples, has the potential to enhance cancer detection in surgical margins and monitoring of 3D cell culture molecular environments. However, in thicker samples, substantial background staining is common despite repeated rinsing...

journal_title：Physics in medicine and biology

authors： Xu X,Wang Y,Xiang J,Liu JTC,Tichauer KM

更新日期：2017-06-21 00:00:00

abstract：:A cost-effective method employing polysulphone, nalidixic acid, 8-methoxypsoralen and phenothiazine as UV dosimeters is presented for evaluating the UV spectrum. The exposure measured by each dosimeter is a function of the source spectrum and the spectral response of the material. Each material has a different spectra...

journal_title：Physics in medicine and biology

authors： Parisi AV,Wong JC,Moore GI

更新日期：1997-01-01 00:00:00

abstract：:Scanned ion pencil beams carry a low-dose envelope which can extend up to several centimeters from the individual beam central axis. Depending on the energy and species of the beam, this halo consists mainly of secondary particles produced by nuclear interactions in the target or of particles undergoing multiple Coulo...

journal_title：Physics in medicine and biology

authors： Schwaab J,Brons S,Fieres J,Parodi K

更新日期：2011-12-21 00:00:00

abstract：:An in vivo probe was compared with a gamma camera for the task of detecting radiolabelled tumour models in a water phantom. The probe, which contained a 1 cm diameter NaI(T1) detector, was designed and used by us for surgical staging studies of gynaecological patients. Tumours were spherical sources of different sizes...

journal_title：Physics in medicine and biology

authors： Barber HB,Barrett HH,Woolfenden JM,Myers KJ,Hickernell TS

更新日期：1989-06-01 00:00:00

abstract：:A standard protocol for performance evaluation of positron emission mammography (PEM) systems has not yet been established. In this work we propose a methodology based on the design of specific phantoms for this imaging modality with component dimensions in accordance with typical breast lesion sizes together with the...

journal_title：Physics in medicine and biology

authors： Torres-Urzúa LF,Alva-Sanchez H,Martinez-Davalos A,García-Pérez FO,Peruyero-Rivas RM,Rodriguez-Villafuerte M

更新日期：2020-07-21 00:00:00

abstract：:Two experimental investigations of the electromagnetic method to measure body composition are presented. In the first experiment, the impedance of a single-loop transmitting antenna, located at the centre of a 150 m helical receiving coil, was observed to have a sharp minimum at 2.40 MHz. The impedance of the antenna ...

journal_title：Physics in medicine and biology

authors： Sutcliffe JF,Smye SW,Smith MA

更新日期：1995-04-01 00:00:00

abstract：:The measurement of output factors (OF) for the small photon beams generated by Leksell Gamma Knife® (LGK) radiotherapy units is a challenge for the physicist due to the under or over estimation of these factors by a vast majority of the detectors commercially available. Output correction factors, introduced in the int...

journal_title：Physics in medicine and biology

authors： Benmakhlouf H,Johansson J,Paddick I,Andreo P

更新日期：2015-05-21 00:00:00

abstract：:Several applications in nuclear medicine require absolute activity quantification of single photon emission computed tomography images. Obtaining a repeatable calibration factor that converts voxel values to activity units is essential for these applications. Because source preparation and measurement of the source ac...

journal_title：Physics in medicine and biology

authors： Anizan N,Wang H,Zhou XC,Wahl RL,Frey EC

更新日期：2015-02-07 00:00:00

abstract：:Radiation dose distributions have been calculated for 188Re and 32P activity on a coronary artery stent. The doses have been calculated both as a function of position along the stent and of depth into the artery wall. Comparisons of the dose from identical activities of 188Re and 32P on the stent show that the major d...

journal_title：Physics in medicine and biology

authors： Fox RA,Henson PW

更新日期：2000-12-01 00:00:00

abstract：:Diffraction-enhanced imaging (DEI) is an analyser-based x-ray imaging method that produces separate images depicting the projected x-ray absorption and refractive properties of an object. Because the imaging model of DEI does not account for ultra-small-angle x-ray scattering (USAXS), the images produced in DEI can co...

journal_title：Physics in medicine and biology

authors： Chou CY,Anastasio MA,Brankov JG,Wernick MN,Brey EM,Connor DM,Zhong Z

更新日期：2007-04-07 00:00:00

abstract：:It seems likely that long term patency of small bore vascular prostheses is dependent upon, among other things, the mechanical properties of their walls. Arteries are visco-elastic but there is no accurate method of measuring the visco-elasticity of arterial substitutes in vivo. The most successful vascular substitute...

journal_title：Physics in medicine and biology

authors： Chapman BL,Charlesworth D

更新日期：1983-09-01 00:00:00

abstract：:A variable Jacobian and weighted backprojection algorithm, used for medical CT, was adapted to perform CT reconstructions on data obtained with a dental panoramic x-ray unit. A detector array, fitted to the unit for the purpose of acquiring digital panoramic radiographs, was used to collect the data. Compensations wer...

journal_title：Physics in medicine and biology

authors： Lee MD,Waggener RG,McDavid WD,Dove SB,Welander U,Tronje G

更新日期：1992-12-01 00:00:00

abstract：:Depth-dose distributions were calculated for thermal and epithermal neutron fluence and capture gamma ray dose rates using a two-dimensional neutron-coupled gamma-ray transport code (DOT 3.5) for gadolinium neutron capture therapy. The results show that (i) a capture gamma-ray dose rate of 10 Gy h-1 was obtained with ...

journal_title：Physics in medicine and biology

authors： Matsumoto T

更新日期：1992-01-01 00:00:00

abstract：:For patients with partial epilepsy, automatic spike detection techniques applied to interictal MEG data often discover several potentially epileptogenic brain regions. An important determination in treatment planning is which of these detected regions are most likely to be the primary sources of epileptogenic activity...

journal_title：Physics in medicine and biology

authors： Ossadtchi A,Mosher JC,Sutherling WW,Greenblatt RE,Leahy RM

更新日期：2005-07-21 00:00:00

abstract：:Automatic tube current modulation (TCM) is used in modern CT devices. This is implemented in the numerical calculation of dose conversion coefficients for CT examinations. For four models of adults, the female and male reference models of ICRP and ICRU and a lighter and a heavier female model, dose conversion coeffici...

journal_title：Physics in medicine and biology

authors： Schlattl H,Zankl M,Becker J,Hoeschen C

更新日期：2010-10-21 00:00:00

abstract：:In order to analyse the respective roles of ion concentration and fractional volume of the interstitial compartment as determinants of the impedance, Z, of renal medullary tissue, a model was needed in which both these factors could be varied independently. An array of blood cell suspensions ions in saline (different ...

journal_title：Physics in medicine and biology

authors： Niewiadomski W,Sadowski J,Badzyńska B,Rasmussen SN

更新日期：1990-11-01 00:00:00

abstract：:Magnetic resonance and ultrasound elastography techniques are now important tools for staging high-grade fibrosis in patients with chronic liver disease. However, uncertainty remains about the effects of simple accumulation of fat (steatosis) and inflammation (steatohepatitis) on the parameters that can be measured us...

journal_title：Physics in medicine and biology

authors： Parker KJ,Ormachea J,Drage MG,Kim H,Hah Z

更新日期：2018-05-17 00:00:00