International Journal of Radiation Research

en The effect of microwave radiation on osteogenesis and osteolysis of rats in the hypergravity condition and the role of Rana sylvatica Le conte oil as a radioprotector Radiation Biology Radiation Biology تحقيق بديع Original Research Background: Microwave Thermotherapy has been gradually used in radiotherapy and it is reported that microwave radiation increases bone demineralization rate independently of temperature. Furthermore, it becomes more and more widespread that the damage caused by the synergistic effect of microwave radiation and hypergravity. The experiment was designed to investigate the effect of microwave radiation on osteogenesis and osteolysis of rats in the hypergravity condition and to observe the role of Rana sylvatica Le conte oil as a radioprotector. Materials and Methods: Wistar rats were exposed to microwave radiation of 200mW/cm2 power density and +6G hypergravity, and the concentrations of osteocalcin, calcitionin, calcium, phosphorus, and hydroxyproline and the activity of alkaline phosphatase were detected in serum. Results: The serum concentrations of osteocalcin and calcitionin and the activity of alkaline phosphatase decreased, while the calcium, phosphorus and hydroxyproline concentrations increased after the synergistic effect of microwave radiation and hypergravity. Rana sylvatica Le conte oil intervention inhibited significantly the decrease of osteocalcin concentration and restrained significantly the increases of hydroxyproline and calcium concentrations in serum. Conclusion: These results imply that the synergistic effect of microwave radiation and hypergravity inhibits osteogenesis and enhances osteolysis in rats causing bone metabolic disturbance, while the injury resulted from microwave radiation and hypergravity could be protected by intervention with Rana sylvatica Le conte oil and it provides an original direction in the investigation of radioprotectors. Iran. J. Radiat. Res., 2011 9(1): 1-8 Microwave radiation, hypergravity, osteogenesis, osteolysis, rana sylvatica Le conte oil. 1 8 http://ijrr.com/browse.php?a_code=A-10-1-378&slc_lang=en&sid=1 S. Pan 790031947532846002194 790031947532846002194 No Y.D. Yang 790031947532846002195 790031947532846002195 No Y.P. Li 790031947532846002196 790031947532846002196 No J.C. Wang 790031947532846002197 790031947532846002197 No J.W. Zhao 790031947532846002198 790031947532846002198 No Y. Wang 790031947532846002199 790031947532846002199 No S.J. Lv 790031947532846002200 790031947532846002200 No W.G. Pan 790031947532846002201 790031947532846002201 No Z.L. Gao gaozhongli@yahoo.com.cn 790031947532846002202 790031947532846002202 Yes

en A comparative study on the increased radioresistance to lethal doses of gamma rays after exposure to microwave radiation and oral intake of flaxseed oil Radiation Biology Radiation Biology تحقيق بديع Original Research Background: Mobile phones, use electromagnetic radiation in the microwave range. On the other hand, there is only one report on radioprotective effects of flaxseed oil. The aim of this study was to investigate the effect of irradiation of rats with microwaves and/or treatment with flaxseed oil on the induction of adaptive response to a subsequent lethal dose (LD) of gamma rays. Materials and Methods: Eighty male rats were randomly divided into 6 groups of 13-15 animals. The animals in the 1st to 5th groups received microwave exposure, microwave+flaxseed oil (dissolved in olive oil), flaxseed (continued after LD), flaxseed, and olive oil. At day 5, all animals were whole-body irradiated with a previously reported LD 50/30 of 8 Gy gamma radiation. The 6th group (controls) received the same LD 50/30, but there was not any other treatment before or after the LD. Results: No death event was observed during days 1-9 after LD irradiation in either group. At day 10, death events started in the 4th group. Thirty days after irradiation of the animals, the survival fractions for the control group, as expected, was 53.3% while there was no death event in the 1st group (survival rate of 100% in microwave-pretreated animals). The survival fractions for the 2nd to 5th groups were 69.2%, 92.3%, 46.1%, and 61.5%, respectively. Conclusion: While these findings open new horizons in radiation protection, the radioresistance induced by microwave radiations emitted by a mobile phone may interfere with the outcome of any subsequent therapeutic application of photons or radioisotopes. Iran. J. Radiat. Res., 2011 9(1): 9-14 Microwave, adaptive response, nonionizing radiation, survival, rat. 9 14 http://ijrr.com/browse.php?a_code=A-10-1-379&slc_lang=en&sid=1 S.M.J. Mortazavi mmortazavi@sums.ac.ir 790031947532846002203 790031947532846002203 Yes M.A. Mosleh-Shirazi 790031947532846002204 790031947532846002204 No A.R. Tavassoli 790031947532846002205 790031947532846002205 No M. Taheri 790031947532846002206 790031947532846002206 No Z. Bagheri 790031947532846002207 790031947532846002207 No R. Ghalandari 790031947532846002208 790031947532846002208 No S. Bonyadi 790031947532846002209 790031947532846002209 No M. Shafie 790031947532846002210 790031947532846002210 No M. Haghani 790031947532846002211 790031947532846002211 No

en Monte Carlo estimation of electron contamination in a 18 MV clinical photon beam Radiation Biology Radiation Biology تحقيق بديع Original Research Background: The electron contamination may reduce or even diminish the skin sparing property of the megavoltage beam. The detailed characteristics of contaminant electrons are presented for different field sizes and cases. Materials and Methods: The Monte Carlo code, MCNPX, has been used to simulate 18 MV photon beam from a Varian Linac-2300 accelerator. All dose measurements were carried out using a PTW-MP2 scanner with an ionization chamber (0.6 CC) at the water phantom. Results: The maximum electron contaminant dose at the surface ranged from 6.1 % for 5 × 5 cm2 to 38.8 % for 40 × 40 cm2 and at the depth of maximum dose was 0.9 % up to 5.77 % for the 5 × 5 cm2 to the 40 × 40 cm2 field sizes, respectively. The additional contaminant electron dose at the surface for the field with tray increased 2.3 % for 10 × 10 cm2, 7.3 % for 20 × 20 cm2, and 21.4 % for 40 × 40 cm2 field size comparing to the standard field without any accessories. This increase for field with tray and shaping block was 5.3 % and 13.3 % for 10 × 10 and 20 × 20 cm2, respectively, while, the electron contamination decreased for the fields with wedge, i.e. 2.2 % for the 10 × 10 cm2 field. Conclusion: The results have provided more comprehensive knowledge of the high-energy clinical beams and may be useful to develop the accurate treatment planning systems capable of taking the electron contamination in to account. Iran. J. Radiat. Res., 2011 9(1): 15-28 Monte Carlo simulation, MV photon beam, electron contamination, relative absorbed dose. 15 28 http://ijrr.com/browse.php?a_code=A-10-1-380&slc_lang=en&sid=1 M. Allahverdi 790031947532846002212 790031947532846002212 No M. Zabihzadeh 790031947532846002213 790031947532846002213 No M.R. Ay mohammadreza_ay@tums.ac.ir 790031947532846002214 790031947532846002214 Yes S.R. Mahdavi 790031947532846002215 790031947532846002215 No M. Shahriari 790031947532846002216 790031947532846002216 No A. Mesbahi 790031947532846002217 790031947532846002217 No H. Alijanzadeh 790031947532846002218 790031947532846002218 No

en Evaluation of the electron energy fluence and angular distributions from a clinical accelerator. A BEAMnrc Monte Carlo study Radiation Biology Radiation Biology تحقيق بديع Original Research Background: Understanding of the incident electron energy and angular distributions from clinical electron accelerators (linacs) is important for dosimetry and treatment planning. The most important goals of this study were to evaluate the energy fluence and angular distributions of electron beams from a Neptun 10PC linac using the Monte Carlo (MC) code. Materials and Methods: The linac electron beams (6, 8, and 10 MeV) were modeled, using the BEAMnrc MC system based on the Electron- Gamma-Shower (EGSnrc) code. Central axis depthdose curves and dose profiles of the electron beams were measured experimentally, and calculated with the MC for three field sizes. In order to benchmarking the simulated models, the calculated and measured dose distributions were compared with Kolmogorov– Smirnov (KS) statistical test. Results: The KS test indicated that the calculated percent depth dose (PDD) and dose profile values for the three electron beam energies well agree with measured data (within 2% everywhere). The results also showed good agreement (discrepancies smaller than 1%) between the simulated electron energy parameters and those calculated from energy-range relationships using equations for the reference field size. Conclusion: The results showed that there was no significant difference between energy fluence curves of each electron beam energy at different field sizes. In addition, the results of the calculated angular distributions showed that the direction of the electron emerged from the treatment head and trimmer applicators were in forward direction. Iran. J. Radiat. Res., 2011 9(1): 29-36 Linac, electron beam, energy fluence, angular distribution, Monte Carlo. 29 36 http://ijrr.com/browse.php?a_code=A-10-1-381&slc_lang=en&sid=1 N. Jabbari njabbarimp@gmail.com 790031947532846002219 790031947532846002219 Yes H. Nedaie 790031947532846002220 790031947532846002220 No A. Zeinali 790031947532846002221 790031947532846002221 No

en Radiation attenuation of boron doped clay for 662, 1173 and 1332 keV gamma rays Radiation Biology Radiation Biology تحقيق بديع Original Research Background: Radiation shielding properties is an important for a material wish can be used the photon attenuation coefficients of clay produced using different rate of boron have been measured for the purpose of radioactive waste disposal. Materials and Methods: The measurement has been performed using gamma spectrometer contains NaI (Tl) detector at the photon energies of 662, 1173 and 1332 keV. The mean free path and transmission rate of the samples were also obtained. Results: From the measurement of linear attenuation coefficients it was found that using boron in the clay increased the linear attenuation coefficients. Conclusion: It can be concluded from this work that the boron is effective to shield radiation and it can be used for storing of nuclear waste. Iran. J. Radiat. Res., 2011 9(1): 37-40 Photon attenuation coefficient, radioactive waste, boron, clay, NaI (Tl). 37 40 http://ijrr.com/browse.php?a_code=A-10-1-382&slc_lang=en&sid=1 I. Akkurt iskender@fef.sdu.edu.tr 790031947532846002222 790031947532846002222 Yes H. Canakci 790031947532846002223 790031947532846002223 No

en Polonium-210 activity in human hair samples and factors affecting its accumulation Radiation Biology Radiation Biology تحقيق بديع Original Research Background: Due to the presence of radioactive minerals such as monazite, the beach sand of the west coast of Kanyakumari exhibits high natural background radiation. Hair is a good indicator of radionuclides in the human body. An attempt is taken to measure the 210Po activity in human hair samples and the factors affecting it. Material and Methods: 210Po activity was analysed in 47 individuals including males and females living in Kanyakumari district, Tamil Nadu, India. The activities were measured using a Nucleonix® Radiation Counting System (RC 605A). Results: The activity was in the range of 9.89 ± 4.43 to 58.85 ± 6.27 milli Becquerel per gram. 210Po activity was observed in the hair samples when compared to the global values were comparatively higher. Conclusion: Hair samples obtained from the users of home-made and medicinal oil had higher concentration of 210Po compared to that of people using branded oils. These high values may be attributed to the hair oil usage and this is a topic of interest for future studies. Iran. J. Radiat. Res., 2011 9(1): 41-47 210Po, human hair, indicator, cosmetics, accumulation. 41 47 http://ijrr.com/browse.php?a_code=A-10-1-383&slc_lang=en&sid=1 C.R. Rathi 790031947532846002224 790031947532846002224 No E.M. Ross 790031947532846002225 790031947532846002225 No S.G. Wesley godwinwesley@yahoo.com 790031947532846002226 790031947532846002226 Yes

en Evaluation of dosimetric characteristics of a grid block fabricated for Mega-voltage grid therapy purposes Radiation Biology Radiation Biology تحقيق بديع Original Research Background: In conventional radiation therapy, regarding normal tissue tolerance, the treatment of bulk tumors is one of the remaining challenges. Grid Radiation Therapy (GRT) is a technique to deliver high doses, approximately 15 – 20 Gy per fraction, to several small volumes located in a large radiation field. This can be performed using a grid block. The current work has concentrated on the dosimetric characteristics of a designed mega-voltage grid, used for a unique treatment modality. Materials and Methods: All measurements performed using a Neptune linear accelerator (9 MV photon beam). A square 16 × 16 array grid block was designed and fabricated. Several dosimetric characteristics including: depth dose, Valley To Peak (VTP) ratio, and grid out-put factor were evaluated using a calibrated diode dosimeter for a range of radiation fields. Results: The percent depth dose curves, measured in the presence of grid block, lie within those measured for the corresponding open field and a narrow beam. At the Dmax, the VTP ratio was found to be within 17% - 28%, while these ranges between 23% - 35% at a depth of 10 cm. The grid out -put factor found to be 0.78 and it slightly decreases with increasing of radiation field size. Conclusion: The VTP ratio found to be dependent strongly on the grid design and manufacturing properties. However, other parameters such as radiation field size and the depth of measurement should also be addressed as important factors. The measured dosimetric characteristics of grid block indicate that the mega-voltage grid therapy can be applied as a possible clinical modality for palliative cases. Iran. J. Radiat. Res., 2011 9(1): 49-56 Grid therapy, palliation, mega-voltage, radiation dosimetry. 49 56 http://ijrr.com/browse.php?a_code=A-10-1-384&slc_lang=en&sid=1 K. Ghazi-khanlou Sani ghazi@umsha.ac.ir 790031947532846002227 790031947532846002227 Yes M. Mohammadi 790031947532846002228 790031947532846002228 No A. Eskandarlo 790031947532846002229 790031947532846002229 No H. Gholam-hosseinian 790031947532846002230 790031947532846002230 No

en Radon exhalation rates from stone and soil samples of Aravali hills in India Radiation Biology Radiation Biology تحقيق بديع Original Research Background: The most popular building materials are soil bricks and different types of stones. Radon is released into ambient air from soil and stones due to ubiquitous uranium and radium in them, thus increasing the airborne radon concentration. The radioactivity in soils is related to radioactivity in the rocks from which the soil is formed. In the present investigation, the radon emanated from soil and stone samples collected from different locations of Aravali range of hills in the Haryana state of Northern India has been estimated. Materials and Methods: For the measurement of radon concentration emanated from these samples, alpha-sensitive LR-115 type II plastic track detectors have been used. The alpha particles emitted from the radon form tracks in these detectors. After chemical etching the track density of registered tracks is used to calculate radon concentration and exhalation rates of radon using required formulae. Results: The radon concentration in stone samples collected from Aravali range of hills varied from 729 Bq m-3 to 1958 Bq m-3 with an average of 1440 ± 134 Bq m-3 whereas it varied from 806 Bq m-3 to 1325 Bq m-3 with an average of 1040 ± 101 Bq m-3 in case of soil samples. Based upon the data, the mass and the surface exhalation rates of radon emanated from them have also been calculated. Conclusion: The measurements indicate normal to some higher levels of radon concentration emanated from the samples collected from Aravali range of hills of north India. Iran. J. Radiat. Res., 2011 9(1): 57-61 Radioactivity, radon concentration, nuclear tracks, exhalation rates, stone, soil. 57 61 http://ijrr.com/browse.php?a_code=A-10-1-385&slc_lang=en&sid=1 R.P. Chauhan chauhanrpc@gmail.com 790031947532846002231 790031947532846002231 Yes