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Phosphorus (P) is an essential macro-element for plants, and understanding the characteristics of the absorption and transport of P in crops is essential. The low availability of P restricts the growth, nitrogen fixation, and yield of soybean plants. In this research, the radioisotope 33P was supplied to the culture solution to trace the absorption and transport of P in nodulated soybean plants monitored using an imaging plate. The absorption rate of 33P was almost the same under the light and dark conditions. The absorption rate of 33P in the decapitated roots was near to that of the intact plants under light. These results indicate that the P absorption is not affected by evapotranspiration over a short time period. Conversely, the 33P transport from the roots to the shoot was significantly lower under dark conditions than it was under light conditions, although some 33P reached the top of the shoots under both the light and dark conditions. The transport of P to the shoots depends on the transpiration supplemented by the root pressure. The multiplication value of the 33P concentration in the xylem sap and transpiration rate was almost equivalent to the transport rate of 33P in the intact shoots. This value may be adaptable and used to estimate the transport rate of P for the diagnosis. [ABSTRACT FROM AUTHOR]

This document explores the impact of pixel size on the quality of digital images in intraoral dental radiography. The research compares two types of imaging plates with different pixel sizes and finds that the plate with smaller pixels (FCR HR) produces higher image quality. The document also references other studies on pixel size and image quality in different radiographic systems. Ultimately, the choice between imaging plates depends on the specific needs and preferences of the dental practitioner. [Extracted from the article]

Phosphorus (P) is an essential macro-element for plants, and understanding the characteristics of the absorption and transport of P in crops is essential. The low availability of P restricts the growth, nitrogen fixation, and yield of soybean plants. In this research, the radioisotope 33P was supplied to the culture solution to trace the absorption and transport of P in nodulated soybean plants monitored using an imaging plate. The absorption rate of 33P was almost the same under the light and dark conditions. The absorption rate of 33P in the decapitated roots was near to that of the intact plants under light. These results indicate that the P absorption is not affected by evapotranspiration over a short time period. Conversely, the 33P transport from the roots to the shoot was significantly lower under dark conditions than it was under light conditions, although some 33P reached the top of the shoots under both the light and dark conditions. The transport of P to the shoots depends on the transpiration supplemented by the root pressure. The multiplication value of the 33P concentration in the xylem sap and transpiration rate was almost equivalent to the transport rate of 33P in the intact shoots. This value may be adaptable and used to estimate the transport rate of P for the diagnosis.

Objectives: Artifacts including scratches and dirt artifacts on the digital intraoral radiographs finally contribute to making inaccurate diagnoses. The aim of this study was to reduce the incidence of artifacts using dual imaging plates (DIPs) in imaging processing. Methods: Conventional X-rays were taken of a porcine mandible embedded in acrylic resin using a DIP which consists of a front IP (FIP) and a back IP (BIP) with some scratches and dirt. The two images of the FIP and BIP were then synthesized and averaged to obtain a conventional DIP image. The following image processing method was used to make a DIP with artifact reduction (DIP+AR) image. A subtraction image of the FIP and BIP was constructed and the standard deviation (SD) was calculated. If the pixel value was over 3SD on the subtraction images, the pixel value of the DIP was swapped with the value on the opposite side of the non-artifact pixel. The conventional and DIP+AR images were also subjectively evaluated. Results: Image processing to create a DIP+AR image was able to reduce the number of artifacts. Medians of number of artifacts evaluated were 2.00 [interquartile range (IQR), 2.50] in DIP images and 0.67 (IQR, 1.29) in DIP+AR images, indicating a significant reduction of number of artifacts in DIP+AR images. Conclusions: DIP+AR image processing can reduce the incidence of artifacts caused by scratches and dirt, and could extend the lifespan of the IP and contribute accurate diagnosis in oral radiology. [ABSTRACT FROM AUTHOR]

The prospects of using crystals with asymmetric reflection geometry to determine the transverse size of relativistic electron beams based on the results of measuring the angular distributions of their radiation in a thin crystal for two distances between it and a coordinate detector are discussed. Experimental testing of this technique is carried out using an imaging plate as a two-dimensional position-sensitive detector. Measurements are made for an electron energy of 255 MeV and the reflection (220) in a silicon crystal with a thickness of 20 microns and a pixel size of 35 µm2. The distances between the crystal and the detector are 0.5 and 1 m. The obtained values of the horizontal and vertical beam sizes and are in satisfactory agreement with the measurement results for optical transition radiation. The possibility of characterizing X-ray plates by comparing the measured and calculated parametric X‑ray (PXR) angular distributions for several reflecting planes of crystals with an asymmetric reflection geometry and an asymmetry parameter ε less than unity is discussed. [ABSTRACT FROM AUTHOR]

We performed tomographic investigation of the most heavily perturbed (thus highly radioactive) rod and its pristine/unirradiated replicate from the target No. 12 of the Swiss neutron spallation source (SINQ). The tomographic dataset reveals the 3D re-distribution of the lead filling inside the irradiated Zircaloy tube. The change in the linear attenuation coefficient of both the lead filling and the Zircaloy tube of the irradiated rod (due to the presence of the entrapped spallation products) in comparison with the pristine/unirradiated material is quantified. The dataset provides valuable input for the enhancement of safety and efficiency of future spallation targets at SINQ. [ABSTRACT FROM AUTHOR]

This publication shows results of a comparison of three techniques for localising radioactive, and U-bearing particles in contrasted samples. Particles are localised by the means of three methods: (1) Fission Tracks (FT), (2) Imaging Plate (IP), and (3) real time autoradiography (BeaQuant®). These techniques were applied to various samples, including a sediment sampled in the vicinity of the Fukushima Dai-Ichi Nuclear Power Plant (FDNPP) and a sample made of pure U oxide particles. In addition, the efficiency of the combination of two methods (FT and IP) to localise specifically anthropogenic U-bearing particles was tested. [ABSTRACT FROM AUTHOR]

Monte Carlo method is widely used for simulation of industrial and medical radiography due to its powerful ability to simulate statistical phenomena such as radiation generation and transport, and detection processes. Digital radiography is practically applied in two branches of computational radiography (CR) and direct radiography (DR). In this study, computational radiography simulation using the FLUKA Monte Carlo code was developed to provide a framework for studying image contrast as one of the most important parameters of image quality. To investigate the contrast a standard aluminum sensitivity component made of ASTM 1647 standard was used. The simulation of this gauge, along with a complete simulation of the X-ray generator and imaging plate, has been done to assess the image contrast, and and a method has been presented to examine the image contrast. In order to validate the proposed method, practical experiments have been carried out on the contrast sensitivity standard gauge. The simulation results obtained through the proposed method are in good agreement with the results of practical experiments.

We measured the response of BAS-TR imaging plate (IP) to energetic aluminum ions up to 222 MeV, and compared it with predictions from a Monte Carlo simulation code using two different IP response models. Energetic aluminum ions were produced with an intense laser pulse, and the response was evaluated from cross-calibration between CR-39 track detector and IP energy spectrometer. For the first time, we obtained the response function of the BAS-TR IP for aluminum ions with a kinetic energy as high as 222 MeV. On close examination of the two IP response models, we confirm that the exponential model fits our experimental data better. Moreover, we find that the IP sensitivity in the exponential model is nearly constant in this energy range, suggesting that the response function can be determined even with little experimental data. [ABSTRACT FROM AUTHOR]

Featured Application: A large low-background shielding box is developed for the autoradiography of environmental samples. The sensitivity of the imaging plate to α-, β-, and γ-rays indicates that most images of environmental samples originate from α- or β-rays, not from γ-rays. This information is helpful in preparing samples for imaging; to that end, we find ideal covering films for samples and show that sample thickness should be thin enough not to reduce the α- or β-rays. The large shielding box is shown to be effective for visualizing the distribution of radionuclides in environmental samples contaminated by nuclear reactor accidents. Autoradiography using imaging plates is a conventional method for the visualization of the distribution of radionuclides. Imaging plates have high sensitivity to the charged particles of α- and β-rays but are also sensitive to γ-rays. When the radioactivity level in the sample is low, a longer exposure time is needed, and shielding of the natural background radiation is necessary. Large imaging plates (e.g., 35 × 40 cm), which can obtain the radioactivity distribution over a wider area, were developed. In this work, a low-background shielding box is developed for large imaging plates, and the shielding characteristics of the box and sensitivities of the imaging plate to α-, β-, and γ-rays are quantitatively investigated. It is shown, by considering the sensitivity of imaging plates to α-, β-, and γ-rays, that most images of environmental samples are the result of α- or β-rays emitted from radionuclides at the sample surface, but not from the whole sample. To exemplify autoradiography using the presented shielding box, some environmental samples contaminated with radioactive fallout from the Fukushima Daiichi Nuclear Power Plant accident are measured. The distribution of radionuclides is clearly visualized and, furthermore, information of the migration of radiocesium in the sample is obtained. [ABSTRACT FROM AUTHOR]

To estimate the beam losses and activation in the J-PARC main ring (MR) tunnel, thermal neutron distribution was measured using gold foil activation detectors with the Cd difference method. Hundred pairs of bare and Cd-covered gold foils were prepared to cover the entire area of the MR tunnel. The relative and absolute activities of the gold foils were measured using an imaging plate and an HP-Ge detector for some reference foils, respectively. A total of 97% of the thermal neutrons were detected in the injection section, where a beam collimation system was installed to localize the beam loss in the MR tunnel. The thermal neutron fluxes were compared with the calculation results from a Monte Carlo simulation code, PHITS. The calculation results were generally in good agreement with the experimental thermal neutron flux distribution. Furthermore, we investigated a simple empirical formula, ϕ th = C Q ∕ S , to estimate the thermal neutron flux in the accelerator room, where Q is the neutron source intensity and S is the total surface area of the room. A coefficient C of 1.61 ± 0.15 was deduced in the MR tunnel, which is within the error range of the previous value measured in the CERN CHARM facility using a 24 GeV/c proton beam despite the different projectile energies and room shapes. The γ dose rates at the same positions as the gold foils were measured as well. A strong correlation was observed between the thermal neutron fluxes and γ dose rates with respect to the surrounding concrete types. This result suggests that the dose rate on the concrete wall can be used to estimate the distribution of the thermal neutron fluxes and the amount of beam loss in the MR. [ABSTRACT FROM AUTHOR]

Abstract Radiocesium depth profiles in Fukushima soil cores were derived with an unfolding method by using an imaging plate with a response matrix for 134Cs, 137Cs, and 40K radionuclides calculated by a PHITS simulation. The unfolded depth profiles were validated by comparison with profiles measured with a Ge detector. The unfolded depth profiles agreed well with those measured by the Ge detector. The depth profiles obtained were obtained with a 1 mm depth bin width and are useful for estimating the migration of radiocesium in soil. Highlights • The radiocesium depth profile was derived from the readout intensity distribution of an imaging plate. • The readout was unfolded with a response matrix for detected and source positions of radiation. • The depth profiles were obtained with a 1 mm depth bin width. [ABSTRACT FROM AUTHOR]

We measured the response of BAS-TR imaging plate (IP) to energetic aluminum ions up to 222 MeV, and compared it with predictions from a Monte Carlo simulation code using two different IP response models. Energetic aluminum ions were produced with an intense laser pulse, and the response was evaluated from cross-calibration between CR-39 track detector and IP energy spectrometer. For the first time, we obtained the response function of the BAS-TR IP for aluminum ions with a kinetic energy as high as 222 MeV. On close examination of the two IP response models, we confirm that the exponential model fits our experimental data better. Moreover, we find that the IP sensitivity in the exponential model is nearly constant in this energy range, suggesting that the response function can be determined even with little experimental data.

Simulating X-ray images is of great importance in industry and medicine. Using such simulation permits us to optimize parameters which affect image's quality without the limitations of an experimental procedure. This study revolves around a novel methodology to simulate a complete industrial X-ray digital radiographic system composed of an X-ray tube and a computed radiography (CR) image plate using Monte Carlo N Particle eXtended (MCNPX) code. In the process of our research, an industrial X-ray tube with maximum voltage of 300 kV and current of 5 mA was simulated. A 3-layer uniform plate including a polymer overcoat layer, a phosphor layer and a polycarbonate backing layer was also defined and simulated as the CR imaging plate. To model the image formation in the image plate, at first the absorbed dose was calculated in each pixel inside the phosphor layer of CR imaging plate using the mesh tally in MCNPX code and then was converted to gray value using a mathematical relationship determined in a separate procedure. To validate the simulation results, an experimental setup was designed and the images of two step wedges created out of aluminum and steel were captured by the experiments and compared with the simulations. The results show that the simulated images are in good agreement with the experimental ones demonstrating the ability of the proposed methodology for simulating an industrial X-ray imaging system. [ABSTRACT FROM AUTHOR]

It is important to understand tritium desorption behavior from plasma-facing materials of a fusion reactor in order to discuss effective tritium recovery method from in-vessel components. However, basic behavior of hydrogen isotopes in W deposition layer is not understood completely. In this study, characterized tungsten deposition layer formed by hydrogen plasma sputtering was exposed to gaseous tritium at 300 °C or 500 °C and tritium desorption behavior by vacuum heating was investigated by the imaging plate technique. For comparison, bare tungsten substrates were exposed to gaseous tritium in the same condition. Initial tritium activity in the deposition layer was much higher than that in the bare substrate. Tritium desorption behavior from tungsten deposition layer was different by the temperature of the layer during tritium exposure process. By heating at 500 °C for 1 h, 97.5% of tritium was desorbed from the layer exposed to tritium at 300 °C. On the other hand, by heating at 500 °C for 2 h, only 44.6% of tritium was desorbed from the layer exposed to tritium at 500 °C. To recover most tritium from W deposition layer and W substrate, heating at above 700 °C is required. [ABSTRACT FROM AUTHOR]

Angular distributions of parametric X-ray radiation (PXR) from 255 MeV electrons incident on a 50 μm thick diamond crystal are presented. Almost all experiments on the angular distributions of PXR have been performed using Si crystals. The purpose of the present work is to extend this research to diamond crystals. An imaging plate was adopted as a two-dimensional position-sensitive X-ray detector, and high-quality PXR angular distribution data were successfully obtained. The measured PXR angular distributions were compared with those predicted theoretically and good agreement was obtained. The cause of the slight difference observed around the center position (Bragg direction) is also discussed. [ABSTRACT FROM AUTHOR]

The identification of alkali-rich components in extraterrestrial materials along with their separation from other constituents is indispensable for subsequent cosmochemical and isotopic studies. This paper presents a simple pre-screening method for such materials by autoradiography using imaging plates (IPs), which is applicable to identification of mm-sized samples containing ca. 30 µg of potassium in the Yamato-74442 chondrite. The detection limit of IPs was ~1 mBq of K under 49 days exposure. The method provides an opportunity to screen meteorite materials non-destructively and to inexpensively check potassium-rich areas and are suitable for the K-Ca and K-Ar (Ar-Ar) age determinations. [ABSTRACT FROM AUTHOR]

The converter configuration for a multi-imaging plate system was investigated for the application of quality assurance in the irradiation field profile for boron neutron capture therapy. This was performed by the simulation calculation using the PHITS code in the fields at the Heavy Water Neutron Irradiation Facility of Kyoto University Reactor. The converter constituents investigated were carbon for gamma rays, and polyethylene with and without LiF at varied 6 Li concentration for thermal, epithermal, and fast neutrons. Consequently, potential combinations of the converters were found for two components, gamma rays and thermal neutrons, for the standard thermal neutron mode and three components of gamma rays, epithermal neutrons, and thermal or fast neutrons, for the standard mixed or epithermal neutron modes, respectively. [ABSTRACT FROM AUTHOR]

Although there are several two-dimensional (2D) dose-distribution measurement methods using proton beam therapy, they all have drawbacks; hence, there is no standard method established worldwide. The purpose of this study was to develop a simple, high-precision 2D distribution measurement method for proton beam therapy that uses an imaging plate and EBT3. First, we expanded the maximum readable dose (saturation dose) in the imaging plate. The method involves (i) the control of the fading phenomenon by an annealing process and (ii) the control of the photostimulated luminescence (PSL) phenomenon using a longpass filter (LPF). In method (i), upon heating at 80 °C, the PSL became 0.485 times the room temperature, and in method (ii), we attenuated the PSL by a factor of 0.245 using an LPF. Thus, by combining methods (i) and (ii), we expanded the saturation dose to 2 Gy. Thus, it was possible to measure the imaging plate and EBT3 in the same dose range. We simultaneously measured the percent depth dose using imaging plate and EBT3. We defined a correction factor to match the measured values-which had a reduced sensitivity because of the linear energy transfer (LET) dependence of the imaging plate and EBT3-with reference data and developed a correction factor function. Subsequently, by defining the relative LET dependence of imaging plate and EBT3 as the relative sensitivity and converting the relationship imaging plate between the relative sensitivity and correction factor into a function, we obtained a sensitivity-correction function. By employing this function, measurements with the same accuracy as the reference data were performed using the imaging plate and EBT3. [ABSTRACT FROM AUTHOR]

Quality assurance of the spatial distributions of neutrons and gamma rays was tried using imaging plates (IPs) and converters to enhance the beam components in the epithermal neutron mode of the Kyoto University Reactor. The converters used were 4 mm thick epoxy resin with B 4 C at 6.85 weight-percent (wt%) 10 B for epithermal neutrons, and 3 mm thick carbon for gamma rays. Results suggested that the IP signal does not need a sensitivity correction regardless of the incident radiation that produces it. [ABSTRACT FROM AUTHOR]

Although image quality control (QC) of digital system requires professionalism and information techniques, the real situation is that accurate image QC has not been carried out due to the lack of information and experienced operators in clinics. Therefore, in the present study, image QC was divided into representative medical images via computed radiography (CR), and a means of maintaining the optimal image quality in clinics is suggested. The QC state of 25 Korean hospitals equipped with CR was assessed by a questionnaire. Based on the answers, experiments were carried out by dividing the data into the CR. In the CR, the systemic QC of the imaging plate (IP) was examined by assessing the management of the IP with a questionnaire. The results in the CR part demonstrated the importance of systemic management and the establishment of standards, such as selection of the appropriate turnover cycle, based on the use of an IP and the management state determined by the questionnaire. This highlights the need to develop a company's own training program for the use of CR. There is little research data on methods of the image QC for CR equipment. Accordingly, equipment companies and operators should establish systemic QC methods through more studies. [ABSTRACT FROM AUTHOR]