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jalali
1394
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2015
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Different aspects of cytochalasin B Blocked micronucleus cytome (CBMN cyt) assay as a comprehensive measurement tool for radiobiological studies, biological dosimetry and genome instability
It is now universally accepted that DNA is the main target for damages caused by physical and chemical genotoxicants. Although there are different methods to measure directly the induced DNA damages but due to fast repair processes in cellular environment, most of the damages would be repaired even before sampling, therefore processed DNA damages, i.e. damages left unrepaired after acting repair machinery is preferable to measure in various exposure scenarios. Various cytogenetic end points are introduced and implemented such as metaphase analysis, sister chromatid exchanges, premature chromosome condensation, translocation assay and micronucleus assay. All of these methods were extensively used for various purposes but among them micronucleus (MN) assay was found more practical because of ease of scoring, potential for automation as well as being nearly as sensitive as other procedures. These characteristics made MN assay very popular for screening of the effects of various genotoxic agents in vitro and in vivo. In this review we try to summarize the main aspects of application of this method in radiobiological studies and genome instability related diseases.
Cytome assay, micronucleus, genome instability, radiobiological studies, biological dosim
100
126
http://ijrr.com/browse.php?a_code=A-10-1-549&slc_lang=en&sid=1
2015/09/16
1394/6/25
2015/09/16
1394/6/25
M.
Salimi
Department of Medical Genetics, Medical Biotechnology Institute, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
salimi@nigeb.ac.ir
0031947532846009740
0031947532846009740
Yes
H.
Mozdarani
Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
0031947532846009741
0031947532846009741
No
en
Out-of-field photon dosimetry study between 3-D conformal and intensity modulated radiation therapy in the management of prostate cancer
Background: The present work aims to study the out-of-field photon calculation accuracy of a commercial treatment planning system (TPS), Oncentra, for three-dimensional conformal radiotherapy (3D-CRT) and intensity modulated radiation therapy (IMRT) treatment techniques from Elekta Synergy medical linear accelerator. Materials and Methods: Accuracy of individual out-of-field dose components was studied by defining a square field of 10 x 10 cm2 in our TPS and it is verified by using ionization chamber and TLDs (Thermoluminescent dosimeter) at 5 cm depth. Using 3D-CRT and IMRT techniques Ca (carcinoma) prostate treatment plans were created using 6 MV photon beam and calculated in Oncentra Masterplan v4.3 planning systems for out-of-field and further compared the same with TLD measurements. Results: Individual components study shows the poor out-of-field calculations in TPS, with respect to that obtained from TLD measurements. Underestimation increases from 10 % to 80 % as a contribution from various components while moving far from field edge. Complex IMRT plans resemble this underestimation of TPS calculations in greater extend. Conclusion: This study quantifies the poor accuracy for out-of-field dose calculations in TPS. No significant difference in 3D-CRT and IMRT plans is found at near field edge. While, as distance from field edge increases, underestimation of TPS in IMRT plan is higher. 10 % – 60 % difference in out-of-field dose was found as distance move from 2 cm to 7.5 cm far from field edge between TPS estimations and the measurements.
TPS, TLD, out-of-field dose, 3D-CRT, IMRT
127
134
http://ijrr.com/browse.php?a_code=A-10-1-550&slc_lang=en&sid=1
2015/09/162015/09/16
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T.
Siji Cyriac
Department of Physics, Noorul Islam Centre for Higher Education, Kumaracoil, Thuckalay, Kanyakumari District, 629 180, Tamilnadu, India
sijicyriacsanju@gmail.com
0031947532846009743
0031947532846009743
Yes
M.M.
Musthafa
Department of Physics, University of Calicut, Thenhipalam, Malappuram, 673 635, Kerala, India
0031947532846009744
0031947532846009744
No
R.
Ganapathi Raman
Department of Physics, Noorul Islam Centre for Higher Education, Kumaracoil, Thuckalay, Kanyakumari District, 629 180, Tamilnadu, India
0031947532846009745
0031947532846009745
No
K.
Abdul Haneefa
INFN and Department of Physics, University of Torino, Via P. Giuria, 10125, Torino, Italy
0031947532846009746
0031947532846009746
No
Saju Bhasi
Department of Radiation Physics, Regional Cancer Center, Trivandrum, 695 011 , Kerala, India
0031947532846009747
0031947532846009747
No
en
Radioactivity of soil at proposed Rooppur Nuclear Power Plant site in Bangladesh
Background: The concentrations and distributions of natural and anthropogenic radioactive materials in soils of the site of Rooppur Nuclear Power Plant (RNPP) were investigated with the aim of evaluating the environmental radioactivity and radiation hazard. Materials and Methods: Soil samples were collected from 40 locations in and around the proposed site of Rooppur Power Plant and determined the activity level by using a gamma-ray spectrometry. Results: The concentrations of 226Ra, 232Th, and 40K in soil samples, radium equivalent activity (Raeq) for soil, absorbed dose rates, external hazard (Hex) values were determined. No artificial radioactivity (137Cs) was found in these samples. Conclusion: This present study provides a baseline of radioactivity and radiation levels in the proposed nuclear power plant site area at Rooppur. It will be utilized to correlate the radioactivity measured after operation of the reactor.
Gamma spectrometry, radioactivity, soil, Rooppur nuclear power pant (RNPP)
135
142
http://ijrr.com/browse.php?a_code=A-10-1-551&slc_lang=en&sid=1
2015/09/162015/09/162015/09/16
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2015/09/162015/09/162015/09/16
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J.
Ferdous
Health Physics Division, Atomic Energy Centre, Dhaka, Bangladesh
ferdous28@yahoo.com
0031947532846009748
0031947532846009748
Yes
A.
Begum
Health Physics Division, Atomic Energy Centre, Dhaka, Bangladesh
0031947532846009749
0031947532846009749
No
A.
Islam
Health Physics Division, Atomic Energy Centre, Dhaka, Bangladesh
0031947532846009750
0031947532846009750
No
en
Natural radioactivity in Indian vegetation samples
Background: Vegetation (food stuff) is grown in soil that contains many radioactive elements such as 238U (uranium), 232Th (thorium) and 40K (potassium), which may get deposited either due to radioactive fallout or/and by absorption from the soil and can pose serious health hazards. Materials and Methods: Natural radioactivity, radiological hazards and annual effective dose assessment was carried out in vegetation samples (vegetables, cereals and fruits) collected from fields and market. Gamma spectrometry using HPGe detector was used. Results: The measured specific activity concentration of 238U (uranium), 232Th (thorium) and 40K (potassium) varied from 10.25 ± 0.94 Bq/kg to 29.13 ± 0.69 Bq/kg, 22.20 ± 2.46 Bq/kg to 58.21 ± 1.15 Bq/kg, and 1158.4 ± 26.05 Bq/kg to 1962.2 ± 18.17 Bq/kg respectively in various vegetable and cereal samples and varied from 2.5 ± 0.16 Bq/kg to 9.8 ± 0.15 Bq/kg, 7.4 ± 1.24 Bq/kg to 18.4 ± 1.39 Bq/kg, and 287.13 ± 11.23 Bq/kg to 815.72 ± 12.50 Bq/kg respectively in various fruit samples studied in the present work. From these values, hazard indices, the minimum and maximum values of absorbed dose and indoor and outdoor annual effective doses were calculated for various samples used in the present investigation. Conclusion: The various values obtained were found to be within the recommended limits. The absorbed dose and annual effective dose for the vegetable and cereal samples in which fertilizers were used to enhance the crop yield were higher than that in fruit samples.
Radiological hazards, vegetation, radium equivalent activity
143
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http://ijrr.com/browse.php?a_code=A-10-1-552&slc_lang=en&sid=1
2015/09/162015/09/162015/09/162015/09/16
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2015/09/162015/09/162015/09/162015/09/16
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K.
Kant
Department of Physics, Aggarwal College Ballabgarh, Haryana, India– 121 004
kkant_67@rediffmail.com
0031947532846009751
0031947532846009751
Yes
R.
Gupta
Department of Physics and Astro Physics, University of Delhi, Delhi, India
0031947532846009752
0031947532846009752
No
R.
Kumari
Department of Physics, Aggarwal College Ballabgarh, Distt. Faridabad, Haryana, India
0031947532846009753
0031947532846009753
No
N.
Gupta
Department of Humanities and Applied Sciences, AITM, Palwal Haryana, India
0031947532846009754
0031947532846009754
No
M.
Garg
Faculty of Humanities and Applied Sciences, YMCAUST, Faridabad (Haryana), India
0031947532846009755
0031947532846009755
No
en
Radio-adaptive response of peripheral blood lymphocytes following bystander effects induced by preirradiated CHO-K1 cells using the micronucleus assay
Background: Radio-adaptive response and bystander effects are known phenomena occurring in cells following exposure to ionizing radiation (IR). In this study we examined possible radio-adaptation of lymphocytes following bystander effects induced by CHO-K1 cells. Materials and Methods: Whole blood and CHO-K1 cells were cultured in RPMI-1640 complete medium. Cells were separately irradiated with various doses of gamma rays. A co-culture was set to examine the bystander effects induced by CHO-K1 cells on lymphocytes exposed later to a challenge dose of 4 Gy. Treated cells were exposed to cytochalasin-B to arrest cells in cytokinesis stage. Micronucleus (MN) as end point was scored in binucleate cells after staining in Giemsa. Results: The frequency of MN increased significantly with increasing dose of radiation both in lymphocytes and CHO-K1 cells (p<0.001). Although, no significant difference was observed between control non-irradiated cells and those exposed to 0.2 Gy (p>0.05). Co-culture of the non-irradiated lymphocytes with pre-irradiated CHO-K1 cells significantly reduced the mean frequency of MN in lymphocytes irradiated with a dose of 4Gy (p<0.001). Conclusion: Results showed that bystander effects induced by gamma-irradiated CHO-K1 cells led to induction of radio-adaptive response in lymphocytes. The mechanism by which radio-adaptive response is induced following bystander effect is not clearly known, however cellular signaling and genome instability induced in cells indirectly might be considered as possible triggering events for radio-adaptive response.
Bystander effect, radio-adaptive response, gamma rays, micronucleus assay
151
156
http://ijrr.com/browse.php?a_code=A-10-1-553&slc_lang=en&sid=1
2015/09/162015/09/162015/09/162015/09/162015/09/16
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2015/09/162015/09/162015/09/162015/09/162015/09/16
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Sh.
Shirani
School of Paramedicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
0031947532846009756
0031947532846009756
No
H.
Mozdarani
Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
Mozdarah@modares.ac.ir
0031947532846009757
0031947532846009757
Yes
A.
Mahmoodzadeh
Novin Medical Radiation Institute, Tehran, Iran
0031947532846009758
0031947532846009758
No
M.
Salimi
Department of Medical Genetics, Medical Biotechnology Institute, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
0031947532846009759
0031947532846009759
No
en
Spatial memory and changes in expression of genes of neurotrophic factors in adult rat brain after fractionated whole brain irradiation
Background: Ionizing radiation causes cognitive impairment in adult brain. However, the effects of various irradiation protocols with fractionated fixed total dose on hippocampal function have not yet been studied. Materials and Methods: Fractionated whole brain irradiation with a total dose of 36 Gy was performed according to the following protocols: 2Gy-18 fractions (2Gy*18), 4Gy-9 fraction (4Gy*9) and 6Gy-6 fractions (6Gy*6). Changes in spatial memory were studied in Morris water maze tests at 12th and 17th day after irradiation with a hidden platform and at 38th day after irradiation without a platform. Levels of expression of brain derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) genes were evaluated using qPCR. Results: Expression of genes of neurotrophic factors (BDNF and VEGF) was decreased at 4th and 8th week after irradiation, the decrease depended on fractionation. The Morris water maze test with a hidden platform showed improvement in long-term spatial memory at 12th and 17th day after irradiation. In the Morris water maze test without platform cognitive deficit was detected only in 6Gy*6 group at 4th week after irradiation. Conclusion: Our study shows that different fractionation protocols affect hippocampal functions differently, and that the greatest negative impact has the protocol with the maximum single dose. In addition, decrease in expression of genes of neurotrophic factors might play an important role in cognitive impairment.
Fractionated radiation, cognitive dysfunction, spatial memory, VEGF, BDNF
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164
http://ijrr.com/browse.php?a_code=A-10-1-554&slc_lang=en&sid=1
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Y.A.
Zorkina
VP Serbsky National Research Center For Social and Forensic Psychiatry, Department of Basic and Applied Neurobiology, Kropotkinskiy side street 23, 119034, Moscow, Russian Federation
zrkyana@gmail.com
0031947532846009760
0031947532846009760
Yes
E.A.
Zubkov
VP Serbsky National Research Center For Social and Forensic Psychiatry, Department of Basic and Applied Neurobiology, Kropotkinskiy side street 23, 119034, Moscow, Russian Federation
0031947532846009761
0031947532846009761
No
Z.I.
Storozheva
VP Serbsky National Research Center For Social and Forensic Psychiatry, Department of Basic and Applied Neurobiology, Kropotkinskiy side street 23, 119034, Moscow, Russian Federation
0031947532846009762
0031947532846009762
No
G.E.
Gorlachev
Burdenko Neurosurgery Institute RAMS, Department of Radiology and Radiosurgery, 4th Tverskaya-Yamskaya st. 16, 125047, Moscow, Russian Federation
0031947532846009763
0031947532846009763
No
A.V.
Golanov
Burdenko Neurosurgery Institute RAMS, Department of Radiology and Radiosurgery, 4th Tverskaya-Yamskaya st. 16, 125047, Moscow, Russian Federation
0031947532846009764
0031947532846009764
No
V.P.
Chekhonin
VP Serbsky National Research Center For Social and Forensic Psychiatry, Department of Basic and Applied Neurobiology, Kropotkinskiy side street 23, 119034, Moscow, Russian Federation
0031947532846009765
0031947532846009765
No
en
Monte Carlo calculation of shielded colpostat effect on rectum received dose in high dose rate brachytherapy with Cobalt-60 sources
Background: In the current study the effect of shielded colpostat on rectum received dose was calculated in cervical brachytherapy using Monte Carlo (MC) method. Materials and Methods: Two 60Co sources of GZP6 brachytherapy unit used for intracavitary treatments were simulated using MCNPX Monte Carlo code. Also the two types of colpostats including shielded and unshielded were simulated inside a water phantom. The radial dose function, depth doses and dose distribution around sources were calculated with spatial dose resolution of 2×2×2 mm. The effect of tungsten shields on rectum dose was studied. Moreover, the accuracy of treatment planning system (TPS) was verified comparing to MC results. Results: Our results showed that shielded colpostats reduce the rectum dose up to 7% according to the MC calculations. Also, it was found less than 3% difference between TPS and MC results in percentage depth dose and radial doses for unshielded case. Conclusion: It can be concluded that the application of shielded colpostats provide a relatively mild protection (7% reduction in dose) for the rectum in intracavitary brachytherapy due to the higher energy of 60Co photons. However, application of shielded colpostats in treatment planning system is desirable for more accurate treatments.
Intracavitary brachytherapy, shielded colpostat, rectum dose, high dose rate brachytherpy, cobalt-60
165
171
http://ijrr.com/browse.php?a_code=A-10-1-556&slc_lang=en&sid=1
2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/17
1394/6/26
2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/17
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A.
Mesbahi
Medical physics department, Medical School, Tabriz University of Medical Sciences, Tabriz, Iran
amesbahi2010@gmail.com
0031947532846009766
0031947532846009766
Yes
A.
Haghzadeh
Engineering Faculty, Medical Radiation Engineering Department, Azad University, Science and Research branch, Tehran, Iran
0031947532846009767
0031947532846009767
No
A.R.
Naseri
Radiation Oncology Department, Imam Hospital, Tabriz, Iran
0031947532846009768
0031947532846009768
No
A.R.
Naseri
Engineering Faculty, Medical Radiation Engineering Department, Azad University, Science and Research branch, Tehran, Iran
0031947532846009769
0031947532846009769
No
en
Determination of human absorbed dose from [153Sm]-Samarium maltolate based on distribution data in rats
Background: Therapeutic radiopharmaceuticals are designed to deliver high doses of radiation to selected target organs with an aim of minimizing unwanted radiation to surrounding healthy tissue. Due to the potential of targeted radiotherapy to treat a wide range of malignant conditions, [153Sm]-samarium maltolate was developed for possible therapeutic applications. Materials and Methods: The organ radiation-absorbed doses have been evaluated for human based on animal data. After intravenous administration of 153Sm-Mal to four groups of rats, they were sacrificed at exact time intervals and the percentage of injected dose per gram of each organ was calculated by direct counting from rat data. Then S values for 153Sm by using specific absorbed fractions were calculated. By taking advantage of the formulation that Medical Internal Radiation Dose suggests, radiation-absorbed doses for all organs were calculated and extrapolated from rat to human. Results: From rat data, it is estimated that a 185-MBq injection of 153Sm-Mal into a human might result in the highest absorbed dose in the lymphoma tissues (liver 176.3, lungs 68, spleen 66.8 and sternum 19 mGy), especially in liver respect to the other tissues. Conclusion: These results suggest 153Sm-Mal as an efficiently new therapeutic agent in order to overcome possible lymphatic malignancies.
Absorbed dose, biodistribution, MIRD, internal dosimetry, 153Sm-Mal
173
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http://ijrr.com/browse.php?a_code=A-10-1-557&slc_lang=en&sid=1
2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/172015/09/17
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2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/172015/09/17
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H.
Rezaeejam
Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
amir.hakimi@aut.ac.ir
0031947532846009770
0031947532846009770
No
A.
Hakimi
Department of Energy Engineering and Physics, Amir Kabir University of Technology, Tehran, Iran
0031947532846009771
0031947532846009771
Yes
A.R.
Jalilian
Nuclear Science and Technology Research Institute, Tehran, Iran
0031947532846009772
0031947532846009772
No
P.
Abbasian
Department of Energy Engineering and Physics, Amir Kabir University of Technology, Tehran, Iran
0031947532846009773
0031947532846009773
No
S.
Shirvani-Aran
Nuclear Science and Technology Research Institute, Tehran, Iran
0031947532846009774
0031947532846009774
No
M.
Ghannadi-Maragheh
Nuclear Science and Technology Research Institute, Tehran, Iran
0031947532846009775
0031947532846009775
No
en
Induction of apoptosis by 900 MHz radiofrequency radiation emitted from a GSM mobile phone simulator in bystander Jurkat cells
Background: Radiation-induced bystander effect is a response which results in damage in non-irradiated cells in response to signals from the irradiated cells. The aim of the present study was to investigate microwave-induced bystander effect from a GSM mobile phone simulator on induction of apoptosis in Jurkat cell line. Materials and Methods: Jurkat cells were divided into three groups of non-irradiated, exposed and bystander (medium transfer from the irradiated cells). The exposed group was subjected to irradiation from GSM mobile simulator for 2h and 12h the medium from irradiated cells was then transferred to the bystander cells. Apoptosis rate was measured12 and 24 hours after treatment by Annex in V 7-AAD kit using flow cytometry. Results: Apoptosis was observed in both exposed and bystander cells of Jurkat cell line. The difference among non-irradiated, exposed and bystander cell groups was significant (p<0.05). Conclusion: From the obtained results it can be concluded that microwave radiation exposure in Jurkat cells leads to a significant increase in the apoptosis rate not only in the exposed cells but also in the bystander cells.
Apoptosis, bystander effect, microwave, radiofrequency (RF), Jurkat cell line
181
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http://ijrr.com/browse.php?a_code=A-10-1-558&slc_lang=en&sid=1
2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/172015/09/172015/09/17
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2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/172015/09/172015/09/17
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S.M.J.
Mortazavi
Department of Medical Physics and Medical Engineering , School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
0031947532846009776
0031947532846009776
No
N.
Erfani
Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
erfanin@sums.ac.ir
0031947532846009777
0031947532846009777
Yes
H.
Mozdarani
Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
0031947532846009778
0031947532846009778
No
R.
Azmoonfar
Radiology Department, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
0031947532846009779
0031947532846009779
No
N.
Shokrpour
School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
0031947532846009780
0031947532846009780
No
en
Proximate analysis of different groups of irradiated alginic acid
Background: Seaweeds contain significant quantities of lipids, protein, vitamins and minerals. Aquavac Ergosan contains 1% alginic acid extracted from two brown seaweeds, Laminaria digitata and Ascophyllum nodosum. Both in vivo and in-vitro researches have mainly been focused on the effect of Ergosan on fish growth, survival rate, reproductive performance and innate immunity in blood and epidermal mucus. Despite numerous studies on the effects of Ergosan on immune system of aquatic animals and evaluation of seaweeds in proximate analysis, there is no data available on proximate analysis of irradiated Ergosan extract (alginic acid). Therefore, the aim of this study was to assess the effect of on different groups of irradiated alginic acid (10, 20, 30, 40 and 50 KGy) for analyzing proximate composition. Materials and Methods: Alginic acid was prepared from the sonicated Ergosan extract. The Alginic acid extracted from Ergosan was irradiated with a gamma cell. The protein and lipid content and Moisture and ash were recorded. Results: Statistical analysis showed no significant differences among all of groups in terms of protein, lipid, ash and moisture. Conclusion: Radiation processing is a very convenient tool for imparting desirable effects in polymeric materials. The polysaccharide degradation by gamma or ultraviolet irradiation is free of initiators. High energy radiation technique can be effectively used to decrease the molecular weight of different polysaccharides such as alginate and Chitosan. Based on the results of this study, gamma irradiation of alginic acid as natural polysaccharide had no effect on crude protein, crude lipid, moisture and ash.
Gamma ray, alginic acid, proximate analysis
187
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http://ijrr.com/browse.php?a_code=A-10-1-559&slc_lang=en&sid=1
2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/172015/09/172015/09/172015/09/17
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2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/172015/09/172015/09/172015/09/17
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M.
Heidarieh
Nuclear Science and Technology Research Institute, Karaj, Iran
mheidarieh@nrcam.org
0031947532846009781
0031947532846009781
Yes
P.
Shawrang
Nuclear Science and Technology Research Institute, Karaj, Iran
0031947532846009782
0031947532846009782
No
M.
Akbari
Nuclear Science and Technology Research Institute, Karaj, Iran
0031947532846009783
0031947532846009783
No
H.
Heidarieh
Islamic Azad University, Branch of Kazeroon, Kazeroon, Iran
0031947532846009784
0031947532846009784
No
en
Some steps towards establishing a tertiary standard dosimetry laboratory at a radiotherapy department
Background: In order to deliver the precise dose to the target in radiotherapy, absorbed dose to water at the reference point should be assessed. When the calibration procedure is performed for a reference dosimeter in the 60Co beam of a Secondary Standard Dosimetry Laboratory (SSDL), the total uncertainty in absorbed dose to water (Dw) is estimated to be approximately 1.5%. This study attempts to re-measure the ND,W factors for all available field chambers at Reza Radiotherapy & Oncology Centre (RROC). Materials and Methods: Consistency and linearity checks were performed for a range of available chambers using a check source. The ND,W factors were also measured for the ionization chambers. All cylindrical chambers have been cross calibrated at 6 MV photon beam using a Siemens Primus Plus Linac. The Plane Parallel Chamber has been cross calibrated at the highest available electron beam and the ND,W factor has been measured. Results: The tolerance of consistency and linearity checks has been reported to be within 0.3%. The ND,W value for field Farmer chamber was found in agreement with certificate within 1%. In contrast for small active volume chambers, the deviation from the SSDL reports was 2.3%. For the plane parallel chamber, the difference between SSDL and Home measurements are found to be 12%. Conclusion: Although the calibration of reference chambers used for absolute dosimetry through a Primary Standard Dosimetry Laboratory (PSDL) or SSDL is recommended, for field chambers this can be done at home department as a Tertiary Standard Dosimetry Laboratory (TSDL).
Cross calibration, ionization chamber, radiation dosimetry, radiation therapy
191
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http://ijrr.com/browse.php?a_code=A-10-1-560&slc_lang=en&sid=1
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S.
Abdollahi
Reza Radiotherapy Oncology Center, Mashhad, Iran
0031947532846009785
0031947532846009785
No
M.
Mohammadi
Department of Medical Physics, Hamadan University of Medical Science, Hamadan, Iran
mohammadi@umsha.ac.ir
0031947532846009786
0031947532846009786
Yes
A.
Ebrahimzadeh Pezeshki
Reza Radiotherapy Oncology Center, Mashhad, Iran
0031947532846009787
0031947532846009787
No
Z.
Alizadeh
Reza Radiotherapy Oncology Center, Mashhad, Iran
0031947532846009788
0031947532846009788
No
en
The comparison of standard lead with individual mold shielding on patient dose
Background: The Shielding methods in radiotherapy due to delivering an accurate radiation dose to cancer tissues and avoiding unnecessary dose to normal tissues are very important. These methods include Lead standard blocks, individual molding and multi leaf collimator (MLC). The MLC method is not still common in Iran radiotherapy centers. Individual molding is better than the lead block shielding because of lower operator error and time consuming. Materials and Methods: This study was performed in Shahid Ramazanzade radiotherapy center of Yazd and intended to compare radiation dose due to the two shielding methods of lead and Cerrobend. The radiation field sizes of head and neck, pelvis, and breast cancer treated by Cobalt unit, 9MV, and 6MV photon beams of Neptun and Compact linear accelerators were studied, respectively. The Absolute and Relative dosimetry were achieved by Farmer ionic chamber and diod detector. Results: The Absolute and Relative dose values which were measured at the two shielding methods of lead standard and Cerrobend individual molding were similar without significantly difference. Conclusion: The miss difference dose between these two methods shielding and the advantages such as saving time, precision, and accuracy lead to preference of individual molding method rather than the lead block shielding.
Shielding, Cerrobend block, lead block, absorbed dose, relative dose, percent depth dose, absolute dose
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http://ijrr.com/browse.php?a_code=A-10-1-561&slc_lang=en&sid=1
2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/172015/09/172015/09/172015/09/172015/09/172015/09/17
1394/6/26
2015/09/162015/09/162015/09/162015/09/162015/09/162015/09/162015/09/172015/09/172015/09/172015/09/172015/09/172015/09/17
1394/6/26
F.
Bouzarjomehri
Shahid Sadoughi University of Medical Sciences, Yazd, Iran
0031947532846009789
0031947532846009789
No
M.
Kiani
Tabriz University of Medical Sciences, Medical Physics, Tabriz, Iran
0031947532846009790
0031947532846009790
No
A.R.
Farajollahi
Tabriz University of Medical Sciences, Medical Physics, Tabriz, Iran
0031947532846009791
0031947532846009791
Yes