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Pilot study of patient and phantom breast dose measurements in Bulgaria

References Avramova-Cholakova S, Vassileva J, Borisova R, Atanasova I. An estimate of the influence of the measurement procedure on patient and phantom doses in breast imaging. Rad Prot Dosim [Internet]. 2008 Apr 21 [cited 2008 May]; 129(1-3): 150-154. Available from: http://rpd.oxfordjournals.org/cgi/content/abstract/129/1-3/150 doi: 10.1093/rpd/ncn139 http://rpd.oxfordjournals.org/cgi/content/abstract/129/1-3/150 Boone JM. Glandular breast dose for monoenergetic and high-energy X-ray beams: Monte Carlo

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Exit Dose Measurement in Therapeutic High Energy Photon Beams and Cobalt-60 Gamma Rays

backscatter thickness. Med Phys 1977; 2: 123-126. Gagnon WF, Hortan JL. Physical factors affecting absorbed dose from cobalt-60 gamma rays and 25 MV X-rays. Med Phys 1979; 6: 285-290. Gerbi B, Khan F. Measurement of dose in the buildup region using fixed separation plan-parallel ionization chambers. Med Phys 1990; 17: 17-26. International Commission on Radiation Units and Measurements. Determination of absorbed dose in patients irradiated by beams of X and gamma rays in radiotherapy

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Measurement of Head Scatter Factor for Linear Accelerators using Indigenously Designed Columnar Mini Phantom

tissue-air ratios (TAR) to high-energy x-ray beams. Radiology. 1970; 96: 437-446 Johns H. E, Cunningham J. R. The Physics of Radiology. 4 th edition. Charles C. Thomas, Springfield. 1983: 336-381. Jursinic P A, Measurement of head scatter factors of linear accelerators with columnar miniphantoms. Med Phys. 2006; 33: 1720-1728. Karzmark C J, Deubert A, Loevinger R. Tissue-phantom ratios—An aid to treatment planning. Brit J Radiol. 1965; 38: 158-159. Khan F M

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Direct and indirect measurements relevant to the assessment of fatigue of the respiratory muscles - review

-75. Mador MJ et al. Diaphragmatic fatigue and high-intensity exercise in patients with chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2000; 161(1): 118-23. Mador MJ, Khan S, Kufel TJ. Bilateral anterolateral magnetic stimulation of the phrenic nerves can detect diaphragmatic fatigue. Chest 2002; 121(2): 452-8. Man WD, Moxham J, Polkey MI. Magnetic stimulation for the measurement of respiratory and skeletal muscle function. Eur Respir J 2004; 24 (5): 846-60. McKenzie DK et al

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Extracting parasite effects of electrical bioimpedance measurements

parameters [ 3 ]. Digital processing may take place for filtering noise and performing calibration of the EIS system prior to impedance spectra calculation. Commercial EIS equipment may use two or four electrodes for impedance measurement, which may have or not have, cable effects compensation. Apart from this available compensation, commonly calibration can be applied externally by the user, such as short and open-circuit techniques. Due to the fact that four-electrode technique measures a transfer impedance, there has not been found in literature such a compensation

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Effective energy measurement using radiochromic film: application of a mobile scanner

effective energy for QA and QC: measurement of half-value layer using radiochromic film density. Australas Phys Eng Sci Med. 2009;32(1),26-29. [5] Gotanda T, Katsuda T, Gotanda R, et al. Half-value layer measurement: simple process method using radiochromic film. Australas Phys Eng Sci Med. 2009;32(3):150-158. [6] Gotanda T, Katsuda T, Gotanda R, et al. Evaluation of effective energy using radiochromic film and a step-shaped aluminum filter. Australas Phys Eng Sci Med. 2011;34(2):213-222. [7] International Specialty Products

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Bones, blood and steel: How bioelectrical impedance analysis is affected by hip fracture and surgical implants

such as ceramics, hydroxyapatites and polyethylenes. These changes can potentially increase or decrease the electrical conductance, and it is difficult to predict how they will affect BIA measurements. If BIA is to be useful in the large group of acute hip fracture patients, or other patient groups undergoing surgery, it is important to determine the influence of fracture, surgery and surgical implants on BIA readings. The aim of this study is to answer the following research questions: 1) Are BIA measurements affected by recent fracture and surgical repair? 2) Are

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Three-dimensional pulmonary monitoring using focused electrical impedance measurements

Introduction The continuous monitoring of the air distribution inside the lungs is of great clinical interest at the bedside, especially in mechanically ventilated patients. One promising concept to achieve this is Electrical Impedance Tomography (EIT). The general idea is to reconstruct impedance changes inside the body from multiple impedance measurements at the body surface [ 5 ]. These measurements are typically performed using 16 or 32 electrodes, which are positioned on a belt around the thorax at a defined height, typically between the 4th and 6st

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Possibilities in the application of machine learning on bioimpedance time-series

Introduction Analysis of the passive electrical properties of tissue (bioimpedance) can be challenging as the data is complex, the data amount can be large, methods of interpretation are vast, and the electrical properties often have a non-linear relation to the biological property of interest. Raw immittance data from bioimpedance measurements are typically presented as admittance, impedance or dielectric parameters, represented by real and imaginary components. As the electrical properties of tissue always are frequency dependent (1), bioimpedance will

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The effect of SSD, Field size, Energy and Detector type for Relative Output Factor measurement in small photon beams as compared with Monte Carlo simulation

: Quantifying the impact of focal spot size on source occlusion and output factors, and exploring miniphantom design for small-field measurements. Med Phys. 2009;26(7):3132-3144. [8] Herrup D, Chu J, Cheung H, Pankuch M. Determination of penumbral widths from ion chamber measurements. Med Phys. 2005;32(12):3636-3640. [9] Nasir MKR, Amjad N, Razzaq A, Siddique MT. Measurement and Analysis of PDDs Profile and Output Factors for Small Field Sizes by cc13 and Micro-Chamber cc01. International Journal of Medical Physics, Clinical Engineering and Radiation Oncology

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