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The Khanmirza plain is one of Iran’s fertile plains that is located in Chaharmahal Bakhtiari province. Agriculture in the area is very prosperous, but the lack of rain and over-harvesting from consumption wells has led to a reduction in groundwater levels, even causing land subsidence. Moreover, the high usage of chemical manures, especially nitrate manures, has increased the number of solutes and chemical materials in the groundwater. Thus, for this plain, making artificial ponds is important to modify the storage of the aquifer. In this study, to define the optimum locations of the artificial ponds, the effect of 12 factors was considered. The analytic hierarchy process (AHP) method was used to introduce the weight of each parameter in comparison to other factors. Afterward, the spatial priority of all factors was derived using the Geographic Information System (GIS) technique. The produced GIS layers were laid on each other and the optimum locations were obtained. Agricultural drainage was an effective index for recharge purposes. The results of the study demonstrated that groundwater level decline got the maximum weight (40%), while the land slope had the minimum weight, since the vicinity to available floodways was considered as an independent criterion. The results also showed that regions with a total area of 18 km2 in north and north-west of the Khanmirza plain could be the optimum and most suitable places for artificial ponds construction.

Cutaneous squamous cell carcinoma (cSCC) ranks second in the frequency of all skin cancers. The balance between keratinocyte proliferation and differentiation is disrupted in the pathological development of cSCC. DLX3 is a homeobox transcription factor which plays pivotal roles in embryonic development and epidermal homeostasis. To investigate the impact of DLX3 expression on cSCC prognosis, we carried out clinicopathologic analysis of DLX3 expression which showed statistical correlation between tumors of higher pathologic grade and levels of DLX3 protein expression. Further, Kaplan-Meier survival curve analysis demonstrated that low DLX3 expression correlated with poor patient survival. To model the function of Dlx3 in skin tumorigenesis, a two-stage dimethylbenzanthracene (DMBA)/12-O-tetradecanoylphorbol 13-acetate (TPA) study was performed on mice genetically depleted of Dlx3 in skin epithelium (Dlx3cKO). Dlx3cKO mice developed significantly more tumors, with more rapid tumorigenesis compared to control mice. In Dlx3cKO mice treated only with DMBA, tumors developed after ~16 weeks suggesting that loss of Dlx3 has a tumor promoting effect. Whole transcriptome analysis of tumor and skin tissue from our mouse model revealed spontaneous activation of the EGFR-ERBB2 pathway in the absence of Dlx3. Together, our findings from human and mouse model system support a tumor suppressive function for DLX3 in skin and underscore the efficacy of therapeutic approaches that target EGFR-ERBB2 pathway.

Diabetic foot ulcers (DFUs) are a life-threatening disease that often result in lower limb amputations and a shortened lifespan. However, molecular mechanisms contributing to the pathogenesis of DFUs remain poorly understood. We use next-generation sequencing to generate a human dataset of pathogenic DFUs to compare to transcriptional profiles of human skin and oral acute wounds, oral as a model of “ideal” adult tissue repair due to accelerated closure without scarring. Here we identify major transcriptional networks deregulated in DFUs that result in decreased neutrophils and macrophages recruitment and overall poorly controlled inflammatory response. Transcription factors FOXM1 and STAT3, which function to activate and promote survival of immune cells, are inhibited in DFUs. Moreover, inhibition of FOXM1 in diabetic mouse models (STZ-induced and db/db) results in delayed wound healing and decreased neutrophil and macrophage recruitment in diabetic wounds in vivo. Our data underscore the role of a perturbed, ineffective inflammatory response as a major contributor to the pathogenesis of DFUs, which is facilitated by FOXM1-mediated deregulation of recruitment of neutrophils and macrophages, revealing a potential therapeutic strategy., Diabetic foot ulcers (DFU) represent a complex disease with limited treatment options. Here, the authors compare human RNASeq patient data from DFU, oral mucosa and skin acute wounds, identifying FOXM1 as a mediator of macrophage and neutrophil recruitment, which contributes to disease pathogenesis and is dysregulated in patients.

Background : It has recently been shown that the parcle size of materials used for radiaon shielding can affect the magnitude of radiaon aenuaon. Over the past years, applicaon of nano-structured materials in radiaon shielding has aracted aenon world-wide. The purpose of this study was to invesgate the shielding properes of the lead-free shields containing micro and nano-sized WO3 against low energy x-rays. Materials and Methods : The radiaon shields were constructed using nano and micro WO3 parcles incorporated into an EPVC polymer matrix. The aenu aon coefficients of the designed shields were evaluated for low energy x-rays (diagnosc radiology energy range). Results : The results indicate that nano-structured WO3/PVC shields have higher photon aenuaon properes comp ared to those of the micro-sized samples. Conclusion: Our experiment clearly shows that the smaller size of nano-structured WO3 parcles can guarantee a beer radiaon shielding property. However, it is too early to draw any conclusion on the possible mechanisms of enhanced aenuaon of nano-sized WO3 parcles.

This investigation is a novel chemiluminescence (CL) reaction strategy to enhance the inherent sensitivity of the luminol–H2O2 CL system for the determination of cysteine. It was found that CL intensity of cysteine in the luminol–H2O2 system could be enhanced strongly in the presence of our synthesized copper hydroxide/copper oxide nanowires (Cu(OH)2/CuO NWs). About 3–6 fold improvement in the sensitivity was observed when cysteine was determined in the presence of colloidal Cu(OH)2/CuO NWs. Structural, morphological and optical properties of the Cu(OH)2/CuO NWs were examined by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and ultraviolet-visible (UV-Vis) spectroscopy. Fourier Transform Infrared Spectroscopy (FT-IR) studies were done to investigate the presence of organic and/or other compounds in the synthesized NWs. In order to explore the CL mechanism, UV-Vis, fluorescence, and CL spectra studies were carried out. It is suggested that the enhancement in the CL intensity of cysteine is due to the fact that luminol, H2O2 and cysteine could be adsorbed on the surface of NWs and all the electron and the energy transfer processes could be facilitated on the surface of NWs. The CL spectra showed that, the luminophor is the excited-state 3-aminophthalate anion (3-AP2−*, the oxidation product of luminol). Moreover, UV-Vis absorption spectra showed that adsorbed cysteine could be oxidized very easy on the surface of NWs and the resulting product along with O2˙− radicals generate more 3-AP2−* anions. Therefore, higher CL intensities could be produced in the presence of prepared NWs. This enhancement effect has not been seen in the CL system of luminol–H2O2–nanoparticles up to now. Based on these findings, a rapid and sensitive assay was developed for the determination of cysteine. Under the optimum conditions, the CL intensity was proportional to the concentration of cysteine in the ranges 0.8 × 10−9 to 8.0 × 10−8 mol L−1 and 8 × 10−8 to 1.0 × 10−6 mol L−1. The limit of detection was 0.69 × 10−9 mol L−1 and percent of relative standard deviations for 50 × 10−9 mol L−1 cysteine (n = 11) was 5.7%. The proposed method was applied successfully for the sensitive determination of cysteine in human plasma and synthesized injection samples.

The Fars province is located in the south-west region of Iran where different nuclear sites has been established, such as Bushehr Nuclear Power Plant. In this research, 92 water samples from the water supplies of Shiraz city and springs of the Fars province were investigated with regard to the concentrations of natural radioactive elements, total uranium, (226)Ra, gross alpha and gross beta. (226)Ra concentration was determined by the (222)Rn emanation method. To measure the total uranium concentration, a laser fluorimetry analyzer (UA-3) was used. The mean concentration of (226)Ra in Shiraz's water resources was 23.9 mBq l(-1), while 93 % of spring waters have a concentration

Medical physicists need dosimeters such as gel dosimeters capable of determining three-dimensional dose distributions with high spatial resolution. To date, in combination with magnetic resonance imaging (MRI), polyacrylamide gel (PAG) polymers are the most promising gel dosimetry systems. The purpose of this work was to investigate the dose rate dependency of the PAGAT gel dosimeter at low dose rates. The gel dosimeter was used for measurement of the dose distribution around a Cs-137 source from a brachytherapy LDR source to have a range of dose rates from 0.97 Gy h−1 to 0.06 Gy h−1. After irradiation of the PAGAT gel, it was observed that the dose measured by gel dosimetry was almost the same at different distances (different dose rates) from the source, although the points nearer the source had been expected to receive greater doses. Therefore, it was suspected that the PAGAT gel is dose rate dependent at low dose rates. To test this further, three other sets of measurements were performed by placing vials containing gel at different distances from a Cs-137 source. In the first two measurements, several plastic vials were exposed to equal doses at different dose rates. An ionization chamber was used to measure the dose rate at each distance. In addition, three TLD chips were simultaneously irradiated in order to verify the dose to each vial. In the third measurement, to test the oxygen diffusion through plastic vials, the experiment was repeated again using plastic vials in a nitrogen box and glass vials. The study indicates that oxygen diffusion through plastic vials for dose rates lower than 2 Gy h−1 would affect the gel dosimeter response and it is suggested that the plastic vials or (phantoms) in an oxygen free environment or glass vials should be used for the dosimetry of low dose rate sources using PAGAT gel to avoid oxygen diffusion through the vials.

The new compounds, (phhyH)2(pydc), 1 and (phhyH)[Ni(pydc)(pydcH)].3H2O, 2, phhy: phenylhydrazine, pydcH2: pyridine-2,6-dicarboxylic acid, were synthesized and characterized by IR, 1H NMR, 13C NMR and UV spectroscopy. The structure of 2 was determined by X-ray crystallography. In the crystal structure, the metal ion was six coordinated by two tridentate (pydc)2− and (pydcH)− groups and each anionic complex unit, [Ni(pydc)(pydcH)]− was accompanied by one (phhyH)+ as counter ion and two water molecules. In compound 2, a large number of O-HOO, N-HO and C-HO hydrogen bonds were observed. These interactions as well as other noncovalent interactions such as ion pairing, C-Oπ and π-π stacking play an important role in the formation and stabilization of the crystal lattice. In the solution study, the equilibrium constants for the binary pydc-phhy proton transfer system, the stoichiometry and stability of complexation of this system with Ni2+ ion in aqueous solution were investigated using potentiometric pH titration method. The stoichiometry of the most abundant species in the solution was compared to the crystalline cited metal ion complexes.

Radiographic imaging has a significant role in the timely diagnosis of the diseases of neonates in intensive care units. The estimation of the dose received by the infants undergoing radiographic examination is of great importance, due to greater more radiosensitivity and longer life expectancy of the neonates and premature babies. In this study, the values of entrance skin dose (ESD), dose area products (DAPs), energy imparted (EI), whole-body dose, effective dose and risk of childhood cancer were estimated using three methods including direct method [using thermoluminescence dosimetry (TLD) chips], indirect method (using tube output) and Monte Carlo (MC) method (using MCNP4C code). In the first step, the ESD of the neonates was directly measured using TLD-100 chips. Fifty neonates, mostly premature, with different weights and gestational ages in five hospitals mostly suffering from respiratory distress syndrome and pneumonia were involved in this study. In the second step, the values of ESD to neonates were indirectly obtained from the tube output in different imaging techniques. The imaging room, incubator, neonates and other components were then simulated in order to obtain the ESD values using the MCNP4C code. Finally, the values of ESD assessed by the three methods were used for calculation of DAP, EI, whole-body dose, effective dose and risk of childhood cancer. The results indicate that the mean ESD per radiograph estimated by the direct, indirect and MC methods are 56.6±4.1, 50.1±3.1 and 54.5±3.3 μGy, respectively. The mean risk of childhood cancer estimated in this study varied between 4.21×10(-7) and 2.72×10(-6).

In this study, dose rate distribution around a spherical 137Cs pellet source, from a low‐dose‐rate (LDR) Selectron remote afterloading system used in gynecological brachytherapy, has been determined using experimental and Monte Carlo simulation techniques. Monte Carlo simulations were performed using MCNP4C code, for a single pellet source in water medium and Plexiglas, and measurements were performed in Plexiglas phantom material using LiF TLD chips. Absolute dose rate distribution and the dosimetric parameters, such as dose rate constant, radial dose functions, and anisotropy functions, were obtained for a single pellet source. In order to investigate the effect of the applicator and surrounding pellets on dosimetric parameters of the source, the simulations were repeated for six different arrangements with a single active source and five non‐active pellets inside central metallic tubing of a vaginal cylindrical applicator. In commercial treatment planning systems (TPS), the attenuation effects of the applicator and inactive spacers on total dose are neglected. The results indicate that this effect could lead to overestimation of the calculated F(r,θ), by up to 7% along the longitudinal axis of the applicator, especially beyond the applicator tip. According to the results obtained in this study, in a real situation in treatment of patients using cylindrical vaginal applicator and using several active pellets, there will be a large discrepancy between the result of superposition and Monte Carlo simulations. PACS number: 87.53.Jw

Fars province is a large populated large province located in the southwest of Iran. This work presents a study of natural and radioactivity levels in soil samples of this province. For this purpose, 126 samples were gathered from different regions of the province and analysed by gamma spectroscopy to quantify radioactivity concentrations of radionuclides using a high-purity germanium detector and spectroscopy system. The results of this investigation show the average concentrations of 271 ± 28 Bq kg(-1), 6.37 ± 0.5 Bq kg(-1), 14.9 ± 0.9 Bq kg(-1) and 26.3 ± 1.9 Bq kg(-1) for (40)K, (137)Cs, (232)Th and (238)U in soil, respectively. Finally, baseline maps were established for the concentrations of each of the radionuclides in different regions. The absorbed dose rate and the annual effective dose (AED) were also calculated for the radionuclides according to the guidelines of UNSCEAR 2000. The average AED from the radioactivity content of soil in this province was found to be 39.9 ± 1.8 μSv.

Background & Objective: Poor physical and psychological health status in chemical warfare victims could result in decreasing quality of sleep. This study was conducted in order to evaluate the effect of using Continuous Care Model on sleep quality in chemical warfare victims with bronchiolitis obliterans. Methods & Materials: A total of 62 chemical warfare victims with bronchiolitis obliterans were recruited to the study. The participants were randomly allocated to experimental and control groups. The Continuous Care Model was used to experimental group for a period of two months. The quality of sleep was measured using Pittsburgh Sleep Quality Index (PSQI) before and after the intervention in both study groups. Data were analyzed using independent sample t-test, and paired t-test in the SPSS-version 15. Results: There were significant differences between experimental and control groups in the means of Subjective Sleep Quality, Sleep Disturbances, Use of Medications, and global scores after the intervention (P

In this work we present the results of a 2-year survey of indoor radon variations in four cities of Lahijan, Ardabil, Sar-Ein and Namin in North and Northwest Iran. We used both passive and active measurements by solid state nuclear track detectors (SSNTDs) with CR-39 polycarbonate and PRASSI Portable radon Gas Surveyor. A total of 1124 samplers in Lahijan, Ardabil, Sar-Ein and Namin were installed. Sampling frequency was seasonal and sampling locations were randomly chosen based on dwelling structures, floors, geological formations, elevation and temperature variation parameters. For quality assurance, 281 active measurements and double sampling were carried out. Based on our results and the results of previous surveys, Ardabil and Lahijan have the second and third highest radon concentration in Iran, respectively (Ramsar is first). The average radon concentration during the year in Lahijan, Ardabil, Sar-Ein and Namin were 163, 240, 160 and 144 Bq/m(3) with medians of 160, 168, 124 and 133 Bq/m(3), respectively. These concentrations give rise to annual effective doses of 3.43 mSv/y for Lahijan and 5.00 mSv/y for Ardabil. The maximum recorded concentration was 2386 Bq/m(3) during winter in Ardabil and the minimum concentration was 55 Bq/m(3) during spring in Lahijan. Relationships between radon concentration and building materials and room ventilation were also studied. The dosimetry calculations showed that these four cities could be categorized as average natural radiation zones. The correlation coefficients relating warm and cold season radon variation data were obtained.

Neutron Fluence rate of a low intense Pu-Be source is measured by Neutron Activation Analysis (NAA) of 197 Au foils. Also, the neutron fluence rate distribution versus energy is calculated using the MCNP-4B code based on ENDF/B-V library. Theoretical simulation as well as our experimental performance are a new experience for Iranians to make reliability with the code for further researches. In our theoretical investigation, an isotropic Pu-Be source with cylindrical volume distribution is simulated and relative neutron fluence rate versus energy is calculated using MCNP-4B code. Variation of the fast and also thermal neutrons fluence rate, which are measured by NAA method and MCNP code, are compared.

Acoustic radiation from a finite spherical source, vibrating with an arbitrary, axisymmetric, time-harmonic surface velocity distribution, while immersed at an arbitrary point near a poroelastic sphere in an unbounded ideal fluid medium is analyzed in an exact manner. The formulation utilizes the appropriate wave-field expansions, along with the translational addition theorems for spherical wave functions in combination with the Biot classic model for the description of poroelastic material behavior, to develop a closed-form solution in form of infinite series. The prime objective is to investigate the dynamic poroelasticity effects on acoustic radiation and its associated field quantities. The analytical results are illustrated with a numerical example, in which the spherical source, excited in vibrational modes of zero-th or first order, is positioned near a water-saturated sandstone sphere. The basic acoustic field quantities such as the modal acoustic radiation impedance load on the source, the radiated far-field pressure directivity pattern, and the radial acoustic intensity distribution are evaluated and discussed for representative values of the parameters characterizing the system.

Magnetic nanoparticles that induce nuclear relaxation are the most promising materials to enhance the sensitivity in Magnetic Resonance Imaging. In order to provide a comprehensive understanding of the magnetic field dependence of the relaxation enhancement in solutions, Nuclear Magnetic Resonance (1)H spin-lattice relaxation for decalin and toluene solutions of various Fe2O3 nanoparticles was investigated. The relaxation experiments were performed in a frequency range of 10 kHz-20 MHz by applying Field Cycling method, and in the temperature range of 257-298 K, using nanoparticles differing in size and shape: spherical--5 nm diameter, cubic--6.5 nm diameter, and cubic--9 nm diameter. The relaxation dispersion data were interpreted in terms of a theory of nuclear relaxation induced by magnetic crystals in solution. The approach was tested with respect to its applicability depending on the magnetic characteristics of the nanocrystals and the time-scale of translational diffusion of the solvent. The role of Curie relaxation and the contributions to the overall (1)H spin-lattice relaxation associated with the electronic spin-lattice and spin-spin relaxation was thoroughly discussed. It was demonstrated that the approach leads to consistent results providing information on the magnetic (electronic) properties of the nanocrystals, i.e., effective electron spin and relaxation times. In addition, features of the (1)H spin-lattice relaxation resulting from the electronic properties of the crystals and the solvent diffusion were explained.

Objectives : Some studies indicate that dentistry is one of the job categories with high potential exposure to elevated levels of extremely low frequency magnetic fields. In spite of this, information on occupational exposure of dentists to these fields is scarce. Studies on other common sources of electromagnetic fields (EMFs) such as mobile base stations have shown alterations in the cortisol level following exposure of humans to these sources. The aim of this study is to compare the level of cortisol among dentists and dentistry students who are being occupationally exposed to EMFs emitted by magnetostrictive cavitrons (case group) and among their counterparts who are not being exposed to these fields (control group). Materials and Methods : In this case-control study, blood samples were collected from 41 dentists and dentistry students, 21 of whom were exposed to EMFs emitted by cavitrons as the case group and 20 who were not exposed as the control group, twice; i.e. before work (at 8:30-9:30 a.m.) and after work (11:30-12:30 a.m.). The samples were coded and the serum cortisol level was investigated using the ELISA method (Cortisol AccuBind ELISA Kits). Results : The serum cortisol level of dentists and dental students in the morning (before starting the work) in the control group was 189.15 ± 110.70 (mean ± SD) whereas it was 157.77 ± 112.03 in those who were occupationally exposed to EMFs produced by the use of cavitrons. This difference was not statistically significant ( P = 0.373). In contrast, the serum cortisol level of the participants in the noon (after stopping the work) in the control group was 136.25 ± 67.91 (mean ± SD) while it was 88.58 ± 52.83 in those who were occupationally exposed to EMFs produced by the use of cavitrons. This time, the observed difference was statistically significant ( P = 0.016). In this light, while the difference between serum cortisol levels of dentists and dental students in the morning and after stopping the work was not statistically significant ( P = 0.06), in the EMF-exposed group the cortisol level decreased significantly from 157.77 ± 112.03 in the morning to 88.58 ± 52.83 in the noon ( P = 0.001). Conclusions : As far as we know, this is the first study that evaluated the effect of occupational exposure of dentists to EMFs on their serum cortisol level. The EMFs produced by magnetostrictive cavitrons can decrease the serum cortisol level in dentists. As cortisol plays an important role in blood pressure regulation, cardiovascular, and immune system function, a low cortisol level may threaten health. More studies are needed to clearly understand the effects of EMFs emitted by magnetostrictive cavitron on the level of stress hormones. As some studies have shown that exposure to EMFs has no effect on the cortisol level, whereas other studies reported either an increase or a decrease in the cortisol level, it can be concluded that the effects of exposure to EMFs may occur only at specific absorbed energies or energy absorption rates (usually known as window) similar to that exists in the case of exposure to the low doses of ionizing radiations.

Dear Editor, Breast cancer is the second most common neoplasia and the first leading cause of cancer death among women in the world (1). Early diagnosis of breast cancer plays a critical role in reducing mortality rates and improving the patient’s prognosis (2, 3). Mammography is an extremely useful technique for detection of breast cancer (4). An important goal in this imaging modality is to obtain the best diagnostic information by delivering the least radiation (5, 6). Some protocols by International Atomic Energy Agency (IAEA) are involved in the process of optimizing the radiation used for imaging, which are related to the selection of appropriate imaging equipment, evaluation of equipment performance in the context of quality assurance programs, radiation protection principles and education of medical and technical staff on the appropriate imaging procedures and protocols (7, 8). Considering these protocols, it is essential to have comprehensive knowledge, attitude and practice of mammography in the divisions, emphasize on the importance of its implementation as a routine and preventive measure for early diagnosis of breast cancer (1, 4). The aim of this study was to investigate the radiation protection principles observance and to evaluate the existing status of radiological practice and equipment performance according to the radiation protection protocols established by IAEA in mammography division in Shiraz. According to the best of our knowledge, there was no evidence for the same study in Iran. A questionnaire-based study was carried out in 5 diagnostic mammography divisions of Shiraz namely Namazi, Faghihi, Hafez, Zeinabieh, and MRI. All of the 30 women staff were interviewed between February 2008 to March 2008. All of them were asked to participate in the study. The refusal rate to participate was very low. The above mentioned questionnaire consisted 5 main categories. First, the audiences were asked about radiation dose measurement units. The second part was about the Annual Maximum Permissible Dose (AMPD) (5, 6), the necessary training in regards to the procedures and quality assurance and radiation programs at the beginning of the work made the third and fourth ones. The fifth was about renewing the licenses. Then the questionnaires were reviewed for information quality and legitimacy, and corrections were made as needed. After reviewing the questionnaires, statistical analysis was performed using SPSS software (Version 10) by descriptive statistics. We found that in mammography divisions in Shiraz, 47% of the staffs had not passed necessary training in regards to the procedure nor quality assurance and radiation program at the beginning of their work (Figure 1). About 80% of personnel had not their licenses renewed by attending the training classes again. Moreover, 80% of the machinery and equipment were not being regulated nor monitored as often as needed. Most of the radiation workers were aware of radiation dose measurement units and AMPD (> 95%). In addition, we found that in 80% of the divisions, there was no special radiation protection shield used for the patients. This study showed that an adequate training of staffs in mammography divisions was required to reduce the patient's radiation dose. Implementation of radiation protection courses and education of practical issues, including radiation dose received by patients and radiation safety, during medical education programs could be an effective method to reduce the patient's dose in medical exposures. Figure 1 Status of Personnel Training in Quality Assurance and Radiation Programs Our findings are similar to other studies in the literature (4, 9). In our study, the interviewed staffs were from five different divisions in Shiraz. Therefore, our results may not apply throughout Iran, but it seems that most divisions have the same problems (4, 10). The lack of awareness becomes particularly pertinent when we consider the number of staffs who received inappropriate training. Further investigation in other parishes of Iran is suggested. Combined to the data of the present study, both could provide better understanding of the existing status of radiological practice and equipment performance in mammography divisions.

Accuracy of treatment planning systems may significantly influence the efficacy of brachytherapy. The purpose of this work is a detailed, varied and independent evaluation of an in‐house brachytherapy treatment planning software called STPS. Operational accuracy of STPS was investigated. Geometric tests were performed to validate entry and reconstruction of positional information from scanned orthogonal films. MCNP4C Monte Carlo code and TLDs were used for simulation and experimental measurement, respectively. STPS data were also compared with those from a commercial planning system (Nucletron PLATO). Discrepancy values between MCNP and STPS data and also those of PLATO and STPS at Manchester system dose prescription points (AL and AR) of tandem and ovoid configurations were 2.5%±0.5% and 5.4%±0.4%, respectively. Similar results were achieved for other investigated configurations. Observed discrepancies between MCNP and STPS at the dose prescription point and at 1 cm from the tip of the vaginal applicator were 4.5% and 25.6% respectively, while the discrepancy between the STPS and PLATO data at those points was 2.3%. The software showed submillimeter accuracy in its geometrical reconstructions. In terms of calculation accuracy, similar to PLATO, as attenuation of the sources and applicator body is not considered, dose was overestimated at the tip of the applicator, but based on the available criteria, dose accuracy at most points were acceptable. Our results confirm STPS's geometrical and operational reliability, and show that its dose computation accuracy is comparable to an established commercial TPS using the same algorithm. PACS number: 87.53.Jw

The effect of lithographic patterning on electrodeposit thickness uniformity was investigated in a series of experiments. Copper was electrodeposited from an acid‐sulfate solution onto a specially patterned cathode under controlled agitation provided by a reciprocating paddle. The thickness nonuniformity resulting from a difference in "active‐area‐density" between adjacent zones was measured by profilometry. At current densities far below the mass‐transfer limit, the thickness distributions agreed well with predictions from a recently developed secondary‐current‐distribution model, in which each zone is treated as a continuum. Since this "secondary" model was found to be insufficient to describe behavior at higher current densities, it was extended to include a simple treatment of mass transfer. The resulting "tertiary" model better described the observed behavior. It was discovered that the influence of mass transfer can either decrease or increase the nonuniformity, depending on the importance of radially enhanced diffusion at individual features.

A model has been developed to predict current distribution in electrodeposition onto substrates that contain lithographic patterns. The aim of the work was to understand the strong effects that substrate patterning can exert on the thickness distribution of plated films. Based on the familiar potential‐theory model for secondary current distribution in electrochemical cells, the model is applicable at length scales that are large compared to the individual features of a pattern. The pattern is described entirely as a continuous distribution of "active‐area density," a property that reflects any relative change in the electroactive area of the substrate due to the pattern. The active‐area density enters the expression that relates the surface overpotential to the current density. An implementation of the model, using the boundary‐element method, has been applied to several problems that illustrate the effects of substrate patterning on current distribution. For each example, the dimensionless groups that characterize the current distribution have been identified, general solutions have been obtained over wide parameter ranges, and behavioral trends have been interpreted.

A recent first principles theory for “anomalous” diffusion, which accounts for the effect of a protracted macromolecular response to a perturbation, is used to quantitatively predict the results from successive differential sorption experiments in the benzene/atactic polystyrene system. The physical constants in the theory are evaluated for the conditions of the experiment without reference to any non-Fickian diffusion data. The theoretical predictions are in reasonable agreement with the experimental observations.

Un modele numerique est utilise pour examiner comment l'uniformite de la distribution du courant sur une electrode plane peut etre amelioree en utilisant une electrode auxiliaire coplanaire

Purpose: I-131 is one of the most frequent radionuclides used in nuclear medicine departments. The radiation workers, who manipulate the unsealed radio-toxic iodine, should be monitored for internal contamination. In this study a protocol was established for estimating I-131 activity absorbed in the thyroid glands of the nuclear medicine staff in normal working condition and also in accidents. Methods: I-131 with the activity of 10 μCi was injected inside the thyroid gland of a home-made anthropomorphic neck phantom. The phantom is made up of PMMA as soft tissue, and Aluminium as bone. The dose rate at different distances from the surface of the neck phantom was measured using a scintillator detector for duration of two months. Then, calibration factors were obtained, for converting the dose rate at each distance to the iodine activity inside the thyroid. Results: According to the results of this study, the calibration factors for converting the dose rates (nSv/h) at distances of 0cm, 1cm, 6cm, 11cm, and 16cm to the activity (kBq) inside the thyroid were found to be 0.03, 0.04, 0.14, 0.29, and 0.49 . Conclusion: This method can be effectively used for quick estimation of the I-131 concentration inside the thyroid of the staffmore » for daily checks in normal working conditions and also in accidents.« less

This paper discusses an accident, which occurred in one of the radiation application centres in Iran, follow-up investigations as well as lessons learnt. In January 2004 the Regulatory Authority was informed through a university radiation protection officer of an accident regarding orphan sources. Investigations revealed that one Am-Be and three (137)Cs sources in the container were subject to extensive heat due to burning of the container and melting of the paraffin content of the container; consequently, sources were stuck to the side wall of the container, but they were still undamaged and no radioactive leaking had occurred. Further investigations showed that the container had been given to the above mentioned centre a long time before by a foreign well-logging company without notifying the Regulatory Authority. Follow-up measurements and assessments indicated that the collective effective dose due to the accident is unlikely to be more than 21 mSv; consequently, no severe deterministic effect to individuals was expected. The findings showed that the main reasons for the accident were as follows: (1) violation of obligation under radiation protection regulations by the owner of the sources; (2) leaving the sources in an improper storage condition; (3) unauthorised access to the radiation sources at the owner centre; and (4) lack of an integrated national registration system in the Regulatory Authority.

Weekly average suspended particulate matter (SPM) concentrations were measured in four locations in Shiraz, Iran. Sampling was carried out from July 1999 and continued until July 2000. Instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS) methods were employed to obtain the weekly concentrations of Pb, Br, V, Ca, Al, Fe, Cu, Cr, Mn, Sc and Zn. The mean annual concentrations (in μg/m3) of 11 elements were found to be: Pb 0.545 (±33.8%), Br 0.413 (±34.1%), V 0.009 (±28.2%), Ca 13.36 (±24.5%), Al 2.56 (±46.3%), Fe 2.62 (±38.7%), Cu 0.122 (±41.4%), Cr 0.015 (±35.8%), Mn 0.053 (±35.5%), Sc 0.0008 (±37.5%) and Zn 0.085 (±25.2%). The results of the study show that vehicle (traffic) pollution in Shiraz is higher than WHO and EPA standards and natural and industrial pollution is exceeding international guidelines in some seasons. The findings of the study confirm that the nearby cement factory has a major pollution impact on Shiraz air. Keywords: Air pollution, Elemental analysis, SPM, Shiraz, INAA, AAS, Vehicle pollution, Industrial pollution

Purpose: The purpose of this study is the design and fabrication of a multipurpose anthropomorphic neck and thyroid phantom for use in medical applications (i.e. quality control of images in nuclear medicine, and dosimetry). Methods: The designed neck phantom is composed of seven elliptic cylindrical slices with semi-major axis of 14 and semi-minor axis of 12.5 cm, each having the thickness of 2cm. Thyroid gland, bony part of the neck, and the wind pipe were also built inside the neck phantom. Results: The phantom contains some removable plugs,inside and at its surface to accommodate the TLD chips with different shapes and dimensions, (i.e. rod, cylindrical and cubical TLD chips)for the purpose of medical dosimetry (i.e. in radiology, radiotherapy, and nuclear medicine). For the purpose of quality control of images in nuclear medicine, the removable thyroid gland was built to accommodate the radioactive iodine. The female and male thyroid glands were built in two sizes separately. Conclusion: The designed phantom is a multi-functional phantom which is applicable for dosimetry in diagnostic radiology, radiotherapy, and quality control of images in nuclear medicine.

As part of an effort to dissect the genetic factors involved in cholesterol homeostasis in the mouse model, we report the mapping of 12 new candidate genes using linkage analysis. The genes include: cytoplasmic HMG-CoA synthase (Hmgcs 1, Chr 13), mitochondrial synthase (Hmgcs 2, Chr 3), a synthase-related sequence (Hmgcs 1-rs, Chr 12), mevalonate kinase (Mvk, Chr 5), farnesyl diphosphate synthase (Fdps, Chr 3), squalene synthase (Fdft 1, Chr 14), acyl-CoA:cholesterol acyltransferase (Acact, Chr 1), sterol regulatory element binding protein-1 (Srebf1, Chr 8) and -2 (Srebf2, Chr 15), apolipoprotein A-I regulatory protein (Tcfcoup2, Chr 7), low density receptor-related protein-related sequence (Lrp-rs, Chr 10), and Lrp-associated protein (Lrpap 1, Chr 5). In addition, the map positions for several lipoprotein receptor genes were refined. These genes include: low density lipoprotein receptor (Ldlr, Chr 9), very low density lipoprotein receptor (Vldlr, Chr 19), and glycoprotein 330 (Gp330, Chr 2). Some of these candidate genes are located within previously defined chromosomal regions (quantitative trait loci, QTLs) contributing to plasma lipoprotein levels, and Acact maps near a mouse mutation, ald, resulting in depletion of cholesteryl esters in the adrenals. The combined use of QTL and candidate gene mapping provides a powerful means of dissecting complex traits such as cholesterol homeostasis.

Although synovial lining cells (SLC) have been implicated in the production of hyaluronan (HA), which is found at particularly high concentrations in synovial fluid, the degree to which individual cells within the synovium are adapted to this particular function remains to be elucidated. Uridine diphosphoglucose dehydrogenase (UDPGD) activity is the irreversible, rate-limiting step in the production of UDP-glucuronate, an essential monosaccharide in the synthesis of HA. We have assessed the UDPGD activity, microdensitometrically, in individual lining cells of normal and rheumatoid (RA) synovium, using a modified quantitative cytochemical method. In normal synovium, high activity was confined to the cells of the lining with negligible activity in the deeper subintima. The mean UDPGD activity/cell in lining cells of rheumatoid synovium was significantly lower than the activity in normal SLC. In some samples of RA and normal synovium, a bimodal distribution of cells was evident in the lining on the basis of UDPGD activity, a zone of cells in the basal layers with high UDPGD activity and a separate population of cells in more superficial layers with relatively low UDPGD activity. The results suggest that a particular population of cells is present, consistently in normal and more variably in RA synovial lining, which have high UDPGD activity/cell and may be involved in the production of HA. Furthermore, in RA synovium both the UDPGD activity/cell and the relative proportion of these cells within the lining appear to be decreased.

According to the World Health Organization (WHO), the main health hazard from high radon exposure is an increased risk of lung cancer. In this study, 60 male Balb/c mice (20-30 g) were randomly divided into four groups of 15 animals. The animals in the 1st group were kept for 72 hours in an ordinary cage while the 2nd, 3rd, 4th groups were kept in cages with artificially elevated levels of Rn-220. Radon concentrations in the cages of the 1st, 2nd, 3rd and 4th groups were 19±3, 495±54, 590±110 and 1054±231 Bq m−3, respectively. After 72 h, all animals were whole-body irradiated with a previously reported Lethal Dose (LD) 50/6 of 8.8 Gy of cobalt-60 gamma radiation. Ten days after gamma irradiation, the survival fraction for the control group was 26.7%, while the 2nd, 3rd, and 4th groups had survival rates of 66.7%, 53.3% and 53.3%, respectively. After 15 days, the survival fraction for the control group was zero, while the 2nd, 3rd, and 4th groups had survival rates of 26.7%, 20.0% and 26.7%, respectively. These data clearly show that short-term exposure to elevated levels of radon may induce an adaptive response.

Purpose Nowadays, medical physicists need a dosimeter that can detect three‐dimensional (3‐D) dose distributions with high spatial resolution. To date, in combination with Magnetic Resonance Imaging(MRI), polyacrylamide gel (PAG) polymers are the most promising geldosimetry systems that have the potential to verify 3‐D dose distributions delivered by clinical radiotherapy equipment. The purpose of this research is to investigate the application of PAGAT gel in dosimetry of a low dose rate (LDR) brachytherapysource, by simulation and experimental measurements of TG‐43 report parameters. Material and method Selectron Cs‐137 source, an LDR brachytherapy used in remote afterloading systems, is composed of active and dummy spherical pellets 2.5 mm in diameter. The gel was manufactured using the PAGAT geldosimetry recipe of Venning et al. (2005). The geldosimeter was manufactured inside a fume hood and under normal atmospheric conditions. Dosimetry of a spherical active source was done by means of the PAGAT gel.Results The results of Monte Carlo simulations are in good agreement with measurements and simulations of other investigators. The results of a 36 hour irradiation of PAGAT gel for measurement of F(r, θ) and g(r) showed that the measured R2 parameters were almost the same for different distances although the near points had been expected to receive more dose than the far points. In this experiment, 5 vials containing PAGAT gel were placed at different distances from the Cs‐137 teletherapy source and exposed to an equal dose (5 and 20 Gy). The results indicated that in dose rates less than 0.98 Gy/hr, the geldosimeter did not respond while in high dose rates, the response of the geldosimeter was reliable. Conclusion The experimental results of geldosimetry suggest that PAGAT geldosimeter does not have a suitable response in low dose rates.

Introduction In this study, dose rate distribution around a spherical 137 Cs pellet source, from a low dose rate (LDR) Selectron remote afterloading system, have been determined using Experimental and Monte Carlo Simulation techniques. Materials and Methods:Monte Carlo simulations were performed using MCNP4C code, for a single pellet source in water medium and Plexiglas and measurements were performed in Plexiglas phantom material using LiF TLD chips. Absolute dose rate distribution and the TG‐43 dosimetric parameters such as dose rate constant, radial dose functions and anisotropy functions were obtained for a single pellet source. In order to investigate the effect of the applicator, and surrounding pellets on dosimetric parameters of the source, the simulations were repeated for 6 different arrangements with a single active source and five non‐active pellets inside central metallic tubing of a vaginal cylindrical applicator. In commercial treatment planning systems (TPS) the attenuation effects of the applicator and inactive spacers on total dose are neglected. Results The results indicate that this effect could lead to overestimation of the calculated anisotropy function by up to 7% along the longitudinal axis of the applicator especially beyond the applicator tip. The radial dose function and anisotropy function of the new source design have been tabulated for each configuration. Conclusions Impact of the Applicator and Dummy Pellets on the TG‐43 Parameters of Selectron Cs‐137 Source has been determined using TLD and Monte Carlo calculations. The results indicate neglecting the applicator and dummy pellets could cause significant errors in F(r, θ).

The general purpose Monte Carlo N-Particle Radiation Transport Computer Code (MCNP4C) was used to calculate the equivalent dose to the person or people accompanying patients who have been exposed to radiation that was scattered from the patient. To do the calculations, two homogeneous water phantoms were used to simulate the patient and the accompanying person. Finally, in the case of source specification, only the focus of the X-ray tube was modelled, i.e., as a standard MCNP point source that emits a cone of photon. The X-ray spectra to be used in the MCNP simulations were generated with spectrum generating software. These calculations were done for different patient sizes and radiological operations. Dose measurements were made using standard methods that employ LiF TLD-100 dosimeters. A Thermoluminescent Dosimetry (TLD) card was placed on the main trunk of the body of the accompanying person(s), where the maximum dose was probable. In the case of TLD, for a group of 100 examinations, the dose equivalents ranged from 0.01 μSv to 0.13 mSv, with an average of 0.05 mSv. These results are seen to be in close agreement with Monte Carlo simulations. The results suggest that under the correct technical conditions, the radiation doses that are received by the accompanying person or people in radiodiagnostic examinations can be limited to acceptable values and can certainly be under the limits of a permissible dose to the public (1 mSv per year). However, if exposure is frequently repeated, it is probable that the limits that were mentioned above will be exceeded.