scholarly journals PENGARUH PENGGUNAAN FAKTOR KALIBRASI S-137Cs PADA PENGUKURAN DOSIS SINAR-X DENGAN DETEKTOR IONISASI HP(10) STANDAR SEKUNDER

2020 ◽  
Vol 22 (1) ◽  
pp. 45
Author(s):  
Assef Firnando Firmansyah ◽  
Okky Agassy Firmansyah ◽  
Sri Inang Sunaryati ◽  
Nurman Rajagukguk
Keyword(s):  
Radiation Dose ◽  
Energy Range ◽  
Radiation Energy ◽  
Calibration Factor ◽  
Secondary Standard ◽  
Reference Source ◽  
X Ray ◽  
Dose Variation

<p><em>The value of H<sub>p</sub>(10) can be measured directly using H<sub>p</sub>(10) secondary standard chamber that developed by Physikalisch Technische Bundensalt (PTB), Germany. H<sub>p</sub>(10) secondary standard chamber type T 34035/0046 is connected with electrometer PTW Unidos T 10001 / Ns.11814. In this paper, the exposure was carried out by X-ray sources and <sup>137</sup>Cs for dose and radiation energy variations.The variations energy of X-ray were carried out using ISO 4037-1 quality narrow (N) spectrum within N-40 to N-300, while the radiation dose variations were carried out in the dose within range 0.1 mSv to 20 mSv. The use of the S-<sup>137</sup>Cs calibration factor for the H<sub>p</sub>(10) secondary standard chamber with an X-ray irradiation source were carried out and obtained a fairly good response result not in all energy ranges. The result obtained a relatively constant response to energy of 65 keV to 250 keV (energy quality N-80 to N-250), this corresponds to the deviation obtained i.e ≤ 7% from the normalization reference source of <sup>137</sup>Cs at 662 keV energy. Whereas for deviations below 3%, a relatively constant response has founded in the energy range of 100 keV to 250 keV (energy quality N-120 to N-250). The result obtained linier measurement on variations in dose according to changes in dose variation. The H<sub>p</sub>(10) secondary standard chamber is capable for measuring variations of radiation dose, i.e from variations of 0.1 mSv to 20 mSv.</em></p>

WHY MEASUREMENT OF RADIATION DOSE BY MEDICAL PHYSICIST AND RADIATION ONCOLOGIST BOTH?

2021 ◽  
pp. 219-222
Author(s):  
Rubina Rubina ◽  
Baig M.Q ◽  
Kumar Dev
Keyword(s):  
Radiation Dose ◽  
Gamma Rays ◽  
Biological Effect ◽  
Radiation Energy ◽  
The Body ◽  
X Rays ◽  
Radiation Oncologist ◽  
X Ray ◽  
Γ Rays ◽  
Different Tissues

Many years after the discovery of X-ray's and gamma rays. They have been used empirically in medicine, later on realized that this approach was dangerous mainly in radiotherapy and up to some extent in diagnostic radiology. Thus Means of measuring x-ray/γ-rays had to be found in terms of unit of x-rays quantity dened and accepted. The magnitude of the biological effect desirable in case therapy and undesirable in case of diagnosis. It depends upon how much radiation energy is absorbed by irradiated material. X-ray dosimetry is the measurement of energy absorbed in any material particularly in different tissues of the body.

L X-RAY FLUORESCENCE CROSS-SECTIONS MEASUREMENTS FOR ELEMENTS 56≤Z≤66 IN THE ENERGY RANGE 11-41 keV

1987 ◽  
Vol 48 (C9) ◽  
pp. C8-669-C8-672 ◽  
Author(s):  
S. SINGH ◽  
S. KUMAR ◽  
D. MEHTA ◽  
M. L. GARG ◽  
N. SINGH ◽  
...  
Keyword(s):  
Energy Range ◽  
Cross Sections ◽  
X Ray

A new SOLARIS beamline optimized for X-ray spectroscopy in the tender energy range

2021 ◽  
Vol 489 ◽  
pp. 76-81
Author(s):  
Josef Hormes ◽  
Wantana Klysubun ◽  
Jost Göttert ◽  
Henning Lichtenberg ◽  
Alexey Maximenko ◽  
...  
Keyword(s):  
Energy Range ◽  
X Ray

scholarly journals Optimization of X-ray Investigations in Dentistry Using Optical Coherence Tomography

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4554
Author(s):  
Ralph-Alexandru Erdelyi ◽  
Virgil-Florin Duma ◽  
Cosmin Sinescu ◽  
George Mihai Dobre ◽  
Adrian Bradu ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Radiation Dose ◽  
Imaging Techniques ◽  
Image Resolution ◽  
Optical Coherence ◽  
X Rays ◽  
High Quality ◽  
X Ray

The most common imaging technique for dental diagnoses and treatment monitoring is X-ray imaging, which evolved from the first intraoral radiographs to high-quality three-dimensional (3D) Cone Beam Computed Tomography (CBCT). Other imaging techniques have shown potential, such as Optical Coherence Tomography (OCT). We have recently reported on the boundaries of these two types of techniques, regarding. the dental fields where each one is more appropriate or where they should be both used. The aim of the present study is to explore the unique capabilities of the OCT technique to optimize X-ray units imaging (i.e., in terms of image resolution, radiation dose, or contrast). Two types of commercially available and widely used X-ray units are considered. To adjust their parameters, a protocol is developed to employ OCT images of dental conditions that are documented on high (i.e., less than 10 μm) resolution OCT images (both B-scans/cross sections and 3D reconstructions) but are hardly identified on the 200 to 75 μm resolution panoramic or CBCT radiographs. The optimized calibration of the X-ray unit includes choosing appropriate values for the anode voltage and current intensity of the X-ray tube, as well as the patient’s positioning, in order to reach the highest possible X-rays resolution at a radiation dose that is safe for the patient. The optimization protocol is developed in vitro on OCT images of extracted teeth and is further applied in vivo for each type of dental investigation. Optimized radiographic results are compared with un-optimized previously performed radiographs. Also, we show that OCT can permit a rigorous comparison between two (types of) X-ray units. In conclusion, high-quality dental images are possible using low radiation doses if an optimized protocol, developed using OCT, is applied for each type of dental investigation. Also, there are situations when the X-ray technology has drawbacks for dental diagnosis or treatment assessment. In such situations, OCT proves capable to provide qualitative images.

scholarly journals Radiation dose estimation for pencil beam X-ray luminescence computed tomography imaging

2021 ◽  
pp. 1-12
Author(s):  
Ignacio O. Romero ◽  
Changqing Li
Keyword(s):  
Computed Tomography ◽  
Radiation Dose ◽  
Small Animal ◽  
Pencil Beam ◽  
Computed Tomography Imaging ◽  
Step Size ◽  
Imaging Protocol ◽  
X Ray ◽  
Beam Geometry ◽  
Muscle Tissues

BACKGROUND: Pencil beam X-ray luminescence computed tomography (XLCT) imaging provides superior spatial resolution than other imaging geometries like sheet beam and cone beam geometries. However, the pencil beam geometry suffers from long scan times, resulting in concerns overdose which discourages the use of pencil beam XLCT. OBJECTIVE: The dose deposited in pencil beam XLCT imaging was investigated to estimate the dose from one angular projection scan with three different X-ray sources. The dose deposited in a typical small animal XLCT imaging was investigated. METHODS: A Monte Carlo simulation platform, GATE (Geant4 Application for Tomographic Emission) was used to estimate the dose from one angular projection scan of a mouse leg model with three different X-ray sources. Dose estimations from a six angular projection scan by three different X-ray source energies were performed in GATE on a mouse trunk model composed of muscle, spine bone, and a tumor. RESULTS: With the Sigray source, the bone marrow of mouse leg was estimated to have a radiation dose of 44 mGy for a typical XLCT imaging with six angular projections, a scan step size of 100 micrometers, and 106 X-ray photons per linear scan. With the Sigray X-ray source and the typical XLCT scanning parameters, we estimated the dose of spine bone, muscle tissues, and tumor structures of the mouse trunk were 38.49 mGy, 15.07 mGy, and 16.87 mGy, respectively. CONCLUSION: Our results indicate that an X-ray benchtop source (like the X-ray source from Sigray Inc.) with high brilliance and quasi-monochromatic properties can reduce dose concerns with the pencil beam geometry. Findings of this work can be applicable to other imaging modalities like X-ray fluorescence computed tomography if the imaging protocol consists of the pencil beam geometry.

Encapsulated protamine-hyaluronic acid particles for targeting carboplatin directed by radiation

2017 ◽  
Vol 27 (01n02) ◽  
pp. 37-42
Author(s):  
T. Segawa ◽  
S. Harada ◽  
S. Ehara ◽  
K. Ishii ◽  
T. Sato ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Radiation Dose ◽  
Cancer Treatment ◽  
Standard Error ◽  
Room Temperature ◽  
Pixe Analysis ◽  
X Ray ◽  
Clinical Cancer

Encapsulated protamine-hyaluronic acid particles containing carboplatin were prepared and their ability to release carboplatin was tested in vivo. Protamine–hyaluronic acid particles containing carboplatin were prepared by mixing protamine (1.6 mg) and hyaluronic acid (1.28 mg) into a 5 mg/mL carboplatin solution for 30 min at room temperature. A 1 mL solution of protamine–hyaluronic acid particles was poured into an ampule of COATSOME[Formula: see text] EL-010 (Nichiyu, Tokyo, Japan), shaken three times by hand, and allowed to incubate at room temperature for 15 min. Following that, 10 or 20 Gy of 100 kiloelectronvolt (KeV) soft X-ray was applied. The release of carboplatin was imaged using a microparticle-induced X-ray emission (PIXE) camera. The amount of carboplatin released was expressed as the amount of platinum released and measured via quantitative micro-PIXE analysis. The diameter of the generated encapsulated particles measured [Formula: see text] nm (mean ± standard error). The release of carboplatin from the encapsulated protamine–hyaluronic acid particles was observed under a micro-PIXE camera. The amount of carboplatin released was [Formula: see text] under 10 Gy of radiation, and [Formula: see text] under 20 Gy of radiation, which was a sufficient dose for cancer treatment. However, 10 or 20 Gy of radiation is much greater than the dose used for clinical cancer treatment (2 Gy). Further research to reduce the radiation dose to 2 Gy in order to release sufficient carboplatin for cancer treatment is required.

Estimation of Radiation Doses in X-Ray Visualization of Biological Objects

2014 ◽  
Vol 880 ◽  
pp. 53-56 ◽  
Author(s):  
Sergei Stuchebrov ◽  
Andrey Batranin ◽  
Dan Verigin ◽  
Yelena Lukyanenko ◽  
Maria Siniagina ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Biological Object ◽  
Gas Discharge ◽  
Radiation Doses ◽  
Semiconductor Detectors ◽  
Interior Structure ◽  
Dose Calculations ◽  
Object Control ◽  
X Ray ◽  
Biological Objects

Two setups for X-ray visualization of objects interior structure were designed and assembled in TPU. These radiographic systems are based on linear gas-discharge and GaAs semiconductor detectors. During investigation of biological object control of radiation doses has a high priority. In this report radiation dose calculations in X-ray visualization are presented. These calculation also includes dose calculations of sinograms which are used for reconstruction of tomography slices.

THE AGILE MISSION AND GAMMA-RAY ASTROPHYSICS

2002 ◽  
Vol 17 (12n13) ◽  
pp. 1799-1808 ◽  
Author(s):  
MARCO TAVANI
Keyword(s):  
Energy Range ◽  
Gamma Ray ◽  
Angular Resolution ◽  
Source Monitoring ◽  
Space Mission ◽  
Quick Response ◽  
Scientific Program ◽  
X Ray ◽  
Imaging Capability ◽  
Gamma Ray Imaging

Gamma-ray astrophysics in the energy range between 30 MeV and 30 GeV is in desperate need of arcminute angular resolution and source monitoring capability. The AGILE Mission planned to be operational in 2004-2006 will be the only space mission entirely dedicated to gamma-ray astrophysics above 30 MeV. The main characteristics of AGILE are the simultaneous X-ray and gamma-ray imaging capability (reaching arcminute resolution) and excellent gamma-ray timing (10-100 microseconds). AGILE scientific program will emphasize a quick response to gamma-ray transients and multiwavelength studies of gamma-ray sources.

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