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Tytuł:
Time-of-Flight Positron Emission Tomography with Resistive Plate Chamber Detectors: An Unlikely but Promising Approach
Autorzy:
Couceiro, M.
Crespo, P.
Blanco, A.
Ferreira, N.
Mendes, L.
Ferreira Marques, R.
Fonte, P.
Powiązania:
https://bibliotekanauki.pl/articles/1402607.pdf
Data publikacji:
2015-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.57.uk
29.40.Cs
87.57.cf
87.57.cm
Opis:
The cost-effectiveness of resistive plate chamber detectors and their very good timing characteristics, open the possibility to build affordable time-of-flight positron emission tomography systems with a large axial field-of-view. Simulations suggest that, under reasonable assumptions, the absolute 3D true sensitivity, spatial resolution, and noise equivalent count rate of such systems for human whole-body screening, may exceed that of present crystal-based PET technology. However, due to the lack of energy resolution, although having energy sensitivity, the scatter fraction is expected to be considerably higher than that presented by crystal-based PET scanners. In the present paper, the simulation work done so far to access the expected performance of a resistive plate chamber time-of-flight-PET system with 2400 mm length axial field-of-view, a time resolution of 300 ps full width at half maximum for photons pairs, and depth-of-interaction information, will be revised.
Źródło:
Acta Physica Polonica A; 2015, 127, 5; 1453-1461
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies on Catalase-Like Activity of Some Tc-99m Radiopharmaceuticals
Autorzy:
Çıçek, E.
Dede, B.
Powiązania:
https://bibliotekanauki.pl/articles/1360331.pdf
Data publikacji:
2014-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.57.uk
Opis:
Hydrogen peroxide is an ubiquitous metabolite in living systems, produced at increased levels in a variety of pathological situations. Therefore suppressing or at least controlling $H_2O_2$ production is important. Catalase enzymes can convert hydrogen peroxide into water and dioxygen and a similar role can be played by transition metal ions or some radiopharmaceuticals. (1) $TcO_4^-$, (2) Tc-99m mercaptoacetyltriglycine (MAG3) and (3) Tc-99m methoxyisobutylisonitrile (MIBI) were each tested for their ability to catalyse the disproportionation of hydrogen peroxide in the presence of the added base imidazole. It was found that (2) and (3) exhibit acceptable catalase-like activity compared to the Tc-99m pertechnetate.
Źródło:
Acta Physica Polonica A; 2014, 125, 4; 875-876
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Small Animal PET as Non-Invasive Tool for Preclinical Imaging
Autorzy:
Oteo, M.
Morcillo, M.
Powiązania:
https://bibliotekanauki.pl/articles/1402619.pdf
Data publikacji:
2015-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.57.uk
87.85.Pq
87.57.un
Opis:
Increasingly, in vivo imaging of small laboratory animals has become critical for preclinical biomedical research allowing the non-invasive assessment of biological and biochemical processes in living subjects. Many different positron labeled compounds have been synthesized as tracer that target a range of specific markers or pathways yielding quantitative, spatially and temporally indexed information on normal and diseased tissues such as tumors. Because of its non-invasive nature, nuclear techniques also enable to repeat studies in a single subject, facilitating longitudinal assay designs of rodent models of human cancer, cardiovascular, neurological and other diseases over the entire process, from the inception to progression of the disease, and monitoring the effectiveness of treatment or other interventions (with each animal serving as its own control and thereby reducing biological variability). This also serves to reduce the number of experimental animals required for a particular study. In contrast to cell or tissue culture-based experiments, studies in intact animals incorporate all the interacting physiological factors present in vivo.
Źródło:
Acta Physica Polonica A; 2015, 127, 5; 1483-1486
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radiopharmaceutical Production for PET Imaging in Poland
Autorzy:
Choiński, J.
Powiązania:
https://bibliotekanauki.pl/articles/1402629.pdf
Data publikacji:
2015-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.56.bd
87.57.uk
87.57.un
29.27.-a
41.75.Fr
87.56.bg
87.56.-v
Opis:
At the beginning of 2000 the PET technique was not available in Poland. The structure and organization of the Radiopharmaceuticals Production and Research Centre at the Heavy Ion Laboratory, University of Warsaw is described as an example of a production department. The present status of several radiopharmaceutical production departments is presented which should give a comprehensive outlook of radiopharmaceutical production capabilities in Poland over the next few years.
Źródło:
Acta Physica Polonica A; 2015, 127, 5; 1520-1522
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radiation Protection in PET Room
Autorzy:
Kara, Ü.
Tekin, H.
Akkurt, İ.
Powiązania:
https://bibliotekanauki.pl/articles/1402426.pdf
Data publikacji:
2015-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.50.yk
87.57.uk
Opis:
Applications of radiation in medicine is based on the radiation ability of destroing the tumor cells and creating the images of internal organs. This two features play an important role in the diagnosis and treatment of diseases by radiation. In medicine X-ray and radionuclides being sources of gamma rays as $Tc^{99m},$ $I^{137},$ or $Tl^{201}$ are used for the diagnosis of diseases, as beta particles uses for the treatment of diseases. In nuclear medicine radioactive isotopes are built into pharmaceuticals and create radiopharmaceuticals. Radiopharmaceutical administered to patient gathers in examined organ and gives information on functional and anatomical status of the organ. Radiation workers prepare radiopharmaceuticals, transport it, implement, take diagnostic images and survey the therapy. Their radiological protection is very important. Efficient radiation protection can be achieved by factors of time (reduce the time spent close to radioactive source to minimum), distance (keep maximal distance to radioactive source), and shielding (sufficient amount of protective material placed between the source and body) concepts are the basis.
Źródło:
Acta Physica Polonica A; 2015, 128, 2B; B-375-B-377
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radiation exposure of medical staff in interventional radiology
Autorzy:
Kara, Ü.
Akkurt, I.
Powiązania:
https://bibliotekanauki.pl/articles/1068118.pdf
Data publikacji:
2016-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.50.yk
87.57.uk
Opis:
The aim of this study was to assess the radiation dose received by doctors, nurses, X-ray technician medical staff during cardiac catheterization in a representative sample of the staff in our angiography department. Radiation from X-ray machines can cause serious side effects. Radiation exposure of angiography staff (doctors, nurses, medical staff and X-ray technicians) has been recognized as a necessary hazard in angiography department. The purpose of our work is to determine angiography staff radiation doses during interventional radiology, to identify procedures associated with higher radiation doses, and to determine the effects of various parameters on staff doses. This study was performed at Suleyman Demirel University Medical Faculty Hospital. The procedure of study was performed in an interventional radiology department. We have recorded radiation doses data during all related imaging procedures performed as a part of department activity. The distances from the X-ray tube were 0 cm (doctor), 60 cm (nurse), 120 cm (medical staff) and 180 cm (X-ray technician). It is important to understand the radiation effects on medical staff in interventional radiology procedures. Determinants of radiation risk include not only radiation dose levels but also medical staff number, ages, gender and their position. These factors can increase or decrease the risk of exposure.
Źródło:
Acta Physica Polonica A; 2016, 130, 1; 404-406
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radiation dose in dental radiology
Autorzy:
Kara, Ü.
Yıldırım, D.
Akkurt, I.
Powiązania:
https://bibliotekanauki.pl/articles/1065693.pdf
Data publikacji:
2016-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.50.yk
87.57.uk
Opis:
The radiation is used in a wide range of medical fields, in diagnosis and treatment. Certain body parts, like thyroid, are more specifically affected by exposure to different types of radiation sources. The thyroid is highly susceptible to radiation carcinogenesis and exposure to ionising radiation is the only established cause of thyroid cancer. In this study, we have examined radiation doses measured during diagnosis which used dental panoramic radiography. The measurement has been performed in the Suleyman Demirel University, at PlanmecaProMax 3D (cone beam) imaging unit. The device operates at 66-70 kV, 8-10/22 mA/s.
Źródło:
Acta Physica Polonica A; 2016, 130, 1; 407-408
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preliminary studies of J-PET detector spatial resolution
Autorzy:
Pawlik-Niedźwiecka, M.
Niedźwiecki, S.
Alfs, D.
Białas, P.
Curceanu, C.
Czerwiński, E.
Dulski, K.
Gajos, A.
Głowacz, B.
Gorgol, M.
Hiesmayr, B.
Jasińska, B.
Kisielewska, D.
Korcyl, G.
Kowalski, P.
Kozik, T.
Krawczyk, N.
Krzemień, W.
Kubicz, E.
Mohammed, M.
Pałka, M.
Raczyński, L.
Raj, J.
Rudy, Z.
Shivani, -
Silarski, M.
Skurzok, M.
Sharma, N.
Sharma, S.
Shopa, R.
Strzelecki, A.
Wieczorek, A.
Wiślicki, W.
Zgardzińska, B.
Zieliński, M.
Moskal, P.
Powiązania:
https://bibliotekanauki.pl/articles/1057928.pdf
Data publikacji:
2017-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
29.40.Mc
87.57.uk
87.10.Rt
34.50.-s
Opis:
The J-PET detector, based on long plastic scintillator strips, was recently constructed at the Jagiellonian University. It consists of 192 modules axially arranged into three layers, read out from both sides by digital constant-threshold front-end electronics. This work presents preliminary results of measurements of the spatial resolution of the J-PET tomograph performed with ²²Na source placed at selected position inside the detector chamber.
Źródło:
Acta Physica Polonica A; 2017, 132, 5; 1645-1648
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Perspectives for Highly-Sensitive PET-Based Medical Imaging Using β⁺γ Coincidences
Autorzy:
Thirolf, P.
Lang, C.
Parodi, K.
Powiązania:
https://bibliotekanauki.pl/articles/1402601.pdf
Data publikacji:
2015-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.57.uk
87.57.N-
87.57.C-
Opis:
By employing the triple coincidence between the γ trajectory intersections from β⁺ decaying isotopes emitting a third, prompt, photon ("γ-PET" technique), sub-millimeter spatial resolution can be reached in 3 dimensions for the localization of a point source with a reduced requirement of reconstructed intersections per voxel compared to a conventional PET reconstruction analysis. Results of a Monte-Carlo simulation and image reconstruction study are presented in order to characterize the potential of this technique.
Źródło:
Acta Physica Polonica A; 2015, 127, 5; 1441-1444
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of Cyclotron Production for Radiometal of Zirconium 89
Autorzy:
Dabkowski, A.
Paisey, S.
Talboys, M.
Marshall, C.
Powiązania:
https://bibliotekanauki.pl/articles/1402618.pdf
Data publikacji:
2015-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.57.uk
Opis:
Zirconium 89 ($\text{}^{89}Zr$) is a promising radionuclide for development of new PET agents due to its convenient half life of 78.4 h, $\Beta^{+}$ emission rate of 23%, low maximum energy of 0.9 MeV resulting in good spatial resolution, a stable daughter isotope of yttrium-89 ($\text{}^{89}Y$) and favorable imaging characteristics, with only one significant γ -line of 909 keV emitted during decay alongside the 511 keV positron photons. Our aim was to share over 2 years of experience of producing isotopically pure $\text{}^{89}Zr$ via the $\text{}^{89}Y(p,n)^{89}Zr$ nuclear reaction with a COSTIS Solid Target System (STS) and CYCLONE 18/9 cyclotron. We optimized the yields without producing either of the long-lived impurities $\text{}^{88}Zr$ or $\text{}^{88}Y$. The degradation of the beam energy with 400 and 500 μm thick niobium foils was tested without overheating problems within 2-6 h of irradiation. From repeated measurements of activity, it was clear that there is a bi-exponential decay of radioactivity due to the short lived $\text{}^{89m}Zr$ and $\text{}^{89}Zr$. The measured half life of the longer lived radionuclide was consistent with value for $\text{}^{89}Zr$. The energy spectrum from $\text{}^{89}Zr$ had energy peaks at 511 keV and 909 keV and was consistent with $\text{}^{89}Zr$. Production of $\text{}^{89}Zr$ with 400 ($E_{p}$ = 9.8 MeV) and 500 μ m ($E_{p}$ = 11.6 MeV) thick niobium beam degrader was achieved, without producing either $\text{}^{88}Zr$ or $\text{}^{88}Y$. It was necessary to wait at least 4 hours before measuring the activity and decay correct in order to calculate the $\text{}^{89}Zr$ activity at the end of cyclotron production. Degrading the proton beam to 10 MeV produces radionuclidically pure $\text{}^{89}Zr$ with yields from 8 to 9 MBq/μAh. Whilst this is enough for pre-clinical use, the yield is not enough for either clinical use or commercial supply. Use of thinner beam degraders (400 μm) increases the proton beam energy and increases the radionuclidic yield to 15.5 MBq/μAh whilst maintaining radionuclidic purity.
Źródło:
Acta Physica Polonica A; 2015, 127, 5; 1479-1482
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multiple Scattering and Accidental Coincidences in the J-PET Detector Simulated Using GATE Package
Autorzy:
Kowalski, P.
Moskal, P.
Wiślicki, W.
Raczyński, L.
Bednarski, T.
Białas, P.
Bułka, J.
Czerwiński, E.
Gajos, A.
Gruntowski, A.
Kamińska, D.
Kapłon, Ł.
Kochanowski, A.
Korcyl, G.
Kowal, J.
Kozik, T.
Krzemień, W.
Kubicz, E.
Niedźwiecki, Sz.
Pałka, M.
Rudy, Z.
Salabura, P.
Sharma, N.
Silarski, M.
Słomski, A.
Smyrski, J.
Strzelecki, A.
Wieczorek, A.
Wochlik, I.
Zieliński, M.
Zoń, N.
Powiązania:
https://bibliotekanauki.pl/articles/1402625.pdf
Data publikacji:
2015-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
29.40.Mc
87.57.uk
87.10.Rt
34.50.-s
Opis:
Novel positron emission tomography system, based on plastic scintillators, is developed by the J-PET collaboration. In order to optimize geometrical configuration of built device, advanced computer simulations are performed. Detailed study is presented of background given by accidental coincidences and multiple scattering of gamma quanta.
Źródło:
Acta Physica Polonica A; 2015, 127, 5; 1505-1512
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of Radiation Exposure Dose from Nuclear Medicine Procedures (Tc-99m MAG-3)
Autorzy:
Kara, U.
Yildiz, M.
Akkurt, I.
Powiązania:
https://bibliotekanauki.pl/articles/1031923.pdf
Data publikacji:
2017-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.50.yk
87.57.uk
Opis:
Nuclear medicine is great for viewing the roles of body organs. Medical imaging in nuclear medicine takes radioactive pharmaceuticals and studies their path of progress through patient's body. The principles of nuclear medicine are different from those of diagnostic radiology. The nuclear medicine can study the functioning of body and how it actually works. On the other hand, usage of different kinds of radiopharmaceuticals in nuclear medicine examinations can affect the dose rates. The purpose of our investigation was to estimate the effective dose from most common procedures, performed in nuclear medicine departments. We noted the injection radiation doses, which are used for diagnosis in nuclear medicine clinics. Later patient radiation doses were calculated, according to models recommended in ICRP 106.
Źródło:
Acta Physica Polonica A; 2017, 132, 3; 883-885
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hit Time and Hit Position Reconstruction in the J-PET Detector Based on a Library of Averaged Model Signals
Autorzy:
Moskal, P.
Sharma, N.
Silarski, M.
Bednarski, T.
Białas, P.
Bułka, J.
Czerwiński, E.
Gajos, A.
Kamińska, D.
Kapłon, L.
Kochanowski, A.
Korcyl, G.
Kowal, J.
Kowalski, P.
Kozik, T.
Krzemień, W.
Kubicz, E.
Niedźwiecki, Sz.
Pałka, M.
Raczyński, L.
Rudy, Z.
Rundel, O.
Salabura, P.
Słomski, A.
Smyrski, J.
Strzelecki, A.
Wieczorek, A.
Wiślicki, W.
Wochlik, I.
Zieliński, M.
Zoń, N.
Powiązania:
https://bibliotekanauki.pl/articles/1402622.pdf
Data publikacji:
2015-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.57.uk
07.05.Kf
Opis:
In this article we present a novel method of hit time and hit position reconstruction in long scintillator detectors. We take advantage of the fact that for this kind of detectors amplitude and shape of registered signals depend strongly on the position where particle hits the detector. The reconstruction is based on determination of the degree of similarity between measured and averaged signals stored in a library for a set of well-defined positions along the scintillator. Preliminary results of validation of the introduced method with experimental data obtained by means of the double strip prototype of the J-PET detector are presented.
Źródło:
Acta Physica Polonica A; 2015, 127, 5; 1495-1499
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
GPU Accelerated Image Reconstruction in a Two-Strip J-PET Tomograph
Autorzy:
Białas, P.
Kowal, J.
Strzelecki, A.
Bednarski, T.
Czerwiński, E.
Gajos, A.
Kamińska, D.
Kapłon, Ł.
Kochanowski, A.
Korcyl, G.
Kowalski, P.
Kozik, T.
Krzemień, W.
Kubicz, E.
Moskal, P.
Niedźwiecki, Sz.
Pałka, M.
Raczyński, L.
Rudy, Z.
Rundel, O.
Salabura, P.
Sharma, N.
Silarski, M.
Słomski, A.
Smyrski, J.
Wieczorek, A.
Wiślicki, W.
Zieliński, M.
Zoń, N.
Powiązania:
https://bibliotekanauki.pl/articles/1402623.pdf
Data publikacji:
2015-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.57.nf
87.57.uk
Opis:
We present a fast GPU implementation of the image reconstruction routine, for a novel two strip PET detector that relies solely on the time of flight measurements.
Źródło:
Acta Physica Polonica A; 2015, 127, 5; 1500-1504
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimation of Accidental Coincidences in PET
Autorzy:
Oliver, J.
Rafecas, M.
Powiązania:
https://bibliotekanauki.pl/articles/1402605.pdf
Data publikacji:
2015-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.57.uk
87.57.nf
Opis:
Accidental coincidences are one of the main sources of image degradation in positron emission tomography. It is possible to compensate for their degradation effects, but an accurate method to estimate the randoms rate is required. Two conventional methods are used for random rate estimation: the "singles rate" method and the "delayed window" method. In this work we propose a mathematical model that describes the process of accidental coincidence formation. By using it, we are able to predict the correct number of randoms as well as the estimations provided the singles rate and delayed window methods. The model is used to propose a novel estimation method: the "singles-prompt". The aim of this work is to assess the performance of the singles-prompt method and, specially, the model capabilities at several levels. The results agree with all the predictions of the model. In particular, the singles rate and delayed window estimations behave as described by the model and the singles-prompt method estimates the correct number of randoms regardless of the source distribution and total activities.
Źródło:
Acta Physica Polonica A; 2015, 127, 5; 1449-1452
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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