Takasaki Advanced Radiation Research Institute

Mugineic acid family phytosiderophores (MAs) are metal chelators that are produced in graminaceous plants in response to iron (Fe) deficiency, but current evidence regarding secretion of MAs during zinc (Zn) deficiency is contradictory. Our studies using HPLC analysis showed that Zn deficiency induces the synthesis and secretion of MAs in barley plants. The levels of the HvNAS1, HvNAAT-A, HvNAAT-B, HvIDS2 and HvIDS3 transcripts, which encode the enzymes involved in the synthesis of MAs, were increased in Zn-deficient roots. Studies of the genes involved in the methionine cycle using microarray analysis showed that the transcripts of these genes were increased in both Zn-deficient and Fe-deficient barley roots, probably allowing the plant to meet its demand for methionine, a precursor in the synthesis of MAs. In addition, HvNAAT-B transcripts were detected in Zn-deficient shoots, but not in those that were deficient in Fe. Increased synthesis of MAs in Zn-deficient barley was not due to a deficiency of Fe, because Zn-deficient barley accumulated more Fe than did the control plants, ferritin transcripts were increased in Zn-deficient plants, and Zn deficiency promoted Fe transport from root to shoot. Moreover, analysis using the positron-emitting tracer imaging system (PETIS) confirmed that more 62Zn(II)-MAs than 62Zn2+ were absorbed by the roots of Zn-deficient barley plants. These data suggest that the increased biosynthesis and secretion of MAs arising from a shortage of Zn are not due to an induced Fe deficiency, and that secreted MAs are effective in absorbing Zn from the soil.

Deoxymugineic acid (DMA) is a member of the mugineic acid family phytosiderophores (MAs), which are natural metal chelators produced by graminaceous plants. Rice secretes DMA in response to Fe deficiency to take up Fe in the form of Fe(III)-MAs complex. In contrast with barley, the roots of which secrete MAs in response to Zn deficiency, the amount of DMA secreted by rice roots was slightly decreased under conditions of low Zn supply. There was a concomitant increase in endogenous DMA in rice shoots, suggesting that DMA plays a role in the translocation of Zn within Zn-deficient rice plants. The expression of OsNAS1 and OsNAS2 was not increased in Zn-deficient roots but that of OsNAS3 was increased in Zn-deficient roots and shoots. The expression of OsNAAT1 was also increased in Zn-deficient roots and dramatically increased in shoots; correspondingly, HPLC analysis was unable to detect nicotianamine in Zn-deficient shoots. The expression of OsDMAS1 was increased in Zn-deficient shoots. Analyses using the positron-emitting tracer imaging system (PETIS) showed that Zn-deficient rice roots absorbed less (62)Zn-DMA than (62)Zn(2+). Importantly, supply of (62)Zn-DMA rather than (62)Zn(2+) increased the translocation of (62)Zn into the leaves of Zn-deficient plants. This was especially evident in the discrimination center (DC). These results suggest that DMA in Zn-deficient rice plants has an important role in the distribution of Zn within the plant rather than in the absorption of Zn from the soil.

Space travel has advanced significantly over the last six decades with astronauts spending up to 6 months at the International Space Station. Nonetheless, the living environment while in outer space is extremely challenging to astronauts. In particular, exposure to space radiation represents a serious potential long-term threat to the health of astronauts because the amount of radiation exposure accumulates during their time in space. Therefore, health risks associated with exposure to space radiation are an important topic in space travel, and characterizing space radiation in detail is essential for improving the safety of space missions. In the first part of this review, we provide an overview of the space radiation environment and briefly present current and future endeavors that monitor different space radiation environments. We then present research evaluating adverse biological effects caused by exposure to various space radiation environments and how these can be reduced. We especially consider the deleterious effects on cellular DNA and how cells activate DNA repair mechanisms. The latest technologies being developed, e.g., a fluorescent ubiquitination-based cell cycle indicator, to measure real-time cell cycle progression and DNA damage caused by exposure to ultraviolet radiation are presented. Progress in examining the combined effects of microgravity and radiation to animals and plants are summarized, and our current understanding of the relationship between psychological stress and radiation is presented. Finally, we provide details about protective agents and the study of organisms that are highly resistant to radiation and how their biological mechanisms may aid developing novel technologies that alleviate biological damage caused by radiation. Future research that furthers our understanding of the effects of space radiation on human health will facilitate risk-mitigating strategies to enable long-term space and planetary exploration.

Quantum metrology is a powerful tool for explorations of fundamental physical phenomena and applications in material science and biochemical analysis. While in principle the sensitivity can be improved by increasing the density of sensing particles, in practice this improvement is severely hindered by interactions between them. Here, using a dense ensemble of interacting electronic spins in diamond, we demonstrate a novel approach to quantum metrology to surpass such limitations. It is based on a new method of robust quantum control, which allows us to simultaneously suppress the undesired effects associated with spin-spin interactions, disorder, and control imperfections, enabling a fivefold enhancement in coherence time compared to state-of-the-art control sequences. Combined with optimal spin state initialization and readout directions, this allows us to achieve an ac magnetic field sensitivity well beyond the previous limit imposed by interactions, opening a new regime of high-sensitivity solid-state ensemble magnetometers.

A new approach to quantum sensing uses a tailored control pulse sequence to overcome sensor-sensor interactions that have plagued previous designs, setting the stage for nanoscale sensing with newfound sensitivity.

The real-time translocation of iron (Fe) in barley (Hordeum vulgare L. cv. Ehimehadaka no. 1) was visualized using the positron-emitting tracer (52)Fe and a positron-emitting tracer imaging system (PETIS). PETIS allowed us to monitor Fe translocation in barley non-destructively under various conditions. In all cases, (52)Fe first accumulated at the basal part of the shoot, suggesting that this region may play an important role in Fe distribution in graminaceous plants. Fe-deficient barley showed greater translocation of (52)Fe from roots to shoots than did Fe-sufficient barley, demonstrating that Fe deficiency causes enhanced (52)Fe uptake and translocation to shoots. In the dark, translocation of (52)Fe to the youngest leaf was equivalent to or higher than that under the light condition, while the translocation of (52)Fe to the older leaves was decreased, in both Fe-deficient and Fe-sufficient barley. This suggests the possibility that the mechanism and/or pathway of Fe translocation to the youngest leaf may be different from that to the older leaves. When phloem transport in the leaf was blocked by steam treatment, (52)Fe translocation from the roots to older leaves was not affected, while (52)Fe translocation to the youngest leaf was reduced, indicating that Fe is translocated to the youngest leaf via phloem in addition to xylem. We propose a novel model in which root-absorbed Fe is translocated from the basal part of the shoots and/or roots to the youngest leaf via phloem in graminaceous plants.

Nanodiamonds containing fluorescent Nitrogen-Vacancy (NV) centers are the smallest single particles, of which a magnetic resonance spectrum can be recorded at room temperature using optically-detected magnetic resonance (ODMR). By recording spectral shift or changes in relaxation rates, various physical and chemical quantities can be measured such as the magnetic field, orientation, temperature, radical concentration, pH or even NMR. This turns NV-nanodiamonds into nanoscale quantum sensors, which can be read out by a sensitive fluorescence microscope equipped with an additional magnetic resonance upgrade. In this review, we introduce the field of ODMR spectroscopy of NV-nanodiamonds and how it can be used to sense different quantities. Thereby we highlight both, the pioneering contributions and the latest results (covered until 2021) with a focus on biological applications.

Microtextured polydimethylsiloxane sheets exhibit an exceptionally low reflectance of ≲0.0005 across the entire thermal infrared wavelengths while maintaining high resilience.

(64%) for 30 minutes at 45 °C. The chemical and microstructure analysis showed that the lignin and hemicellulose contents of raw RH had been eliminated, and the crystallinity content of CNC was 67.16%. According to transmission electron microscopy (TEM) morphological analysis, CNC measured 19 ± 3.3 nm in diameter, 195 ± 24 nm in length, and 10.2 ± 6.8 in aspect ratio. The thermal stability of RH and CNC was also investigated using thermogravimetric analysis (TGA). These encouraging findings demonstrated the potential for reusing RH agricultural waste to create CNC and include nanocomposites as a reinforcing material.

for ~35 keV x-ray photons at 100 cm from the collimator surface, respectively. We could image the proton beam tracks by measuring the secondary electron bremsstrahlung x-ray during irradiation of the proton beams, and the ranges for different proton energies could be estimated from the images. The measured ranges from the images were well matched with the Monte Carlo simulation, and slightly smaller than the calculated values. We confirmed that the imaging of the secondary electron bremsstrahlung x-ray emitted during proton irradiation with the developed x-ray camera has the potential to be a new tool for proton range estimations.

This study focused on preparing biodegradable dual-layered mulch film based on polyhydroxyalkanoate (PHA) and polycaprolactone (PCL). The main aim of this study is to prepare mulch film with higher biodegradability for rice seed germination. Common plastic mulch films are mostly non-readily biodegradable and stay as residual in soil for a very long duration leading to an increase in salt content and reduction in water and nutrient movement in the soil. This makes the farmland unusable for agricultural purposes. The PHA and PCL were the ideal options as both have their merits and demerits which compensates each other while being cast into double layers and are highly biodegradable. The novelty of this study emphasizes the attachment of PHA and PCL as a dual layer at different ratios that offers a higher bio-degradability percentage. The dual-layer mulch film is made of PHA as the first layer and a mixture of PHA and PCL at different ratios as the second layer. The ratio of PHA/PCL used was 90:10, 70:30, and 50:50. The dual-layered mulch film was prepared using the hot-press technique and later cross-linked by using electron beam irradiation in order to ensure the strong adherence between the two layers. The gel content analysis was performed to measure the crosslinking percentage. The radiation dose of 30 kGy was chosen as the minimum amount of crosslinking and approximately 3.00% was attained for the course. The mixture of PHA/PCL films with different ratios, PHA and PCL virgin film were subjected to a soil burial bio-degradability test. The PHA and PCL virgin film had shown the highest degradation percentage, almost 48.34% just in five weeks. Further characterization was performed on virgin dual-layered PHA/PCL (100%) based on their higher degradability tendency. The apparent properties, morphology, thermal stability, chemical composition, and mechanical properties of dual-layer PHA/PCL (100%) were tested thoroughly. The thickness and transparency attained for dual-layer PHA/PCL (100%) were around 175.25μm and 110.45%. The thermal properties of both single layer PHA and PCL showed good stability, Meanwhile, the virgin dual-layered PHA/PCL mulch film had shown a poor thermal stability. The peak positioning in FTIR for single layer PHA and PCL at 3042.37cm−1, 2942.37cm−1, 1719.54cm−1,1453.33cm−1,1378.95cm−1 and 1181.48cm−1 remained unchanged in virgin double-layered PHA/PCL film as well. The outcome of the analyses clearly indicates the possibilities of the dual-layer PHA/PCL (100%) with greater bio-degradability. The soil burial biodegradability test needs to be prolonged up to its full potential. The other characteristics such as water permeability, photo permeability, crystallinity, and heat preservation need to be investigated as well.

Emerging immersive high–dynamic range display technologies require not only high peak luminance but also true black levels with hemispherical reflectance below 0.001 (0.1%) to accommodate the wide dynamic range of the human eye (~10 5 ). Such low reflectance materials, denoted here as “supreme black,” must exhibit near-perfect surface antireflection, extremely low in-matrix backscattering, and sufficient optical thickness, which, to date, have only been achieved by fragile sparse materials. We demonstrate a record-low hemispherical reflectance below 0.0002 (absorptance above 0.9998) in a touchproof material by satisfying the three requirements with a superwavelength surface microtexture with nanolevel details, low Mie backscattering composition, and optional additional underlayer. Our supreme black finishes are one to two orders of magnitude blacker than previously developed touchproof super-black materials. Thereby, unprecedented black levels enabling an ambient contrast ratio of ≳10 4 would be provided in display devices, contributing to immersive visual experiences that are critical for seamless remote collaboration and reliable virtual health care.

Although luminescence of water during irradiations of proton and carbon-ion lower energy than the Cerenkov-light threshold were found recently, the sources of the luminescence were not yet obvious. To estimate the sources of the luminescence, we measured the light spectrum of the luminescence of water during carbon-ion irradiations and estimated the sources of the luminescence. Using an ultraviolet (UV) light sensitive charge coupled device (CCD) camera, we measured the luminescence images of water during carbon-ion beam irradiations by changing optical filters, derived the light spectra of the luminescence of water and compared with the calculated results. The intensity of the measured light spectrum of the luminescence of water at the Bragg peak region was decreased as the wavelength of light proportional to ~ λ to the -2.0th power where λ is the wavelength of the light, indicating the source of the luminescence of water can be electromagnetic pulse produced by the dipole displacement inside the water molecules. In the shallow part of the water prior to the Bragg peak, where the Cerenkov-light is included, the spectrum showed steeper curve that is proportional to ~ λ to the -2.6th power, which was similar to the calculated spectrum of Cerenkov-light including the refractive index changes of water with the wavelength of light. From these results, the luminescence of water is thought to be mainly come from electromagnetic pulse produced by the dipole displacement inside the water molecules.

Abstract Low-energy x-ray imaging of the secondary electron bremsstrahlung (SEB) x-ray emitted during carbon-ion irradiation is a promising method for range estimation. However, it remains unclear whether the method can be used for imaging with the clinical dose levels of carbon-ion and whether the bremsstrahlung x-ray can be detected from the deeper part of the body. To clarify these points, we developed a new high resolution low-energy x-ray camera and conducted imaging of the SEB x-ray during the irradiation of carbon-ions of different energies and intensities. Imaging was also tried with an x-ray camera using a human-head-sized, 17 cm diameter cylindrical phantom. To develop a high resolution imaging detector for a low-energy x-ray, we used a 20 × 20 × 0.5 mm thick cerium-doped yttrium aluminum perovskite, YA1O 3 (YAP(Ce)) scintillator plate, which was optically coupled to a 25 mm square high quantum efficiency (HQE) type position sensitive photomultiplier tube (PSPMT). The imaging detector was encased in a 2 cm thick tungsten container and a pinhole collimator was attached to its camera head. After evaluating the camera’s performance, SEB x-ray imaging was tried during irradiation of the carbon-ion and compared the results with a Monte Carlo simulation. We imaged the beam tracks by the SEB x-ray in real-time during irradiation of the carbon-ion and imaging and range estimation were possible even with near clinical dose level of 7.5 × 10 8 particles of carbon-ion. Clear images of a SEB x-ray were also obtained for a 17 cm diameter cylindrical phantom. The measured images were good agreement with the Monte Carlo simulation. We confirmed that our developed YAP(Ce) camera is promising for imaging SEB x-rays during irradiation of carbon-ions even near clinical conditions.

This paper investigates the selectivity of GMA-based-non-woven fabrics adsorbent towards copper ion (Cu) functionalized with several aliphatic amines. The aliphatic amines used in this study were ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA), and tetraethylenepentamine (TEPA). The non-woven polyethylene/polypropylene fabrics (NWF) were grafted with glycidyl methacrylate (GMA) via pre-radiation grafting technique, followed by chemical functionalization with the aliphatic amine. To prepare the ion recognition polymer (IRP), the functionalized amine GMA-grafted-NWF sample was subjected to radiation crosslinking process along with the crosslinking agent, divinylbenzene (DVB), in the presence of Cu ion as a template in the matrix of the adsorbent. Functionalization with different aliphatic amine was carried out at different amine concentrations, grafting yield, reaction temperature, and reaction time to study the effect of different aliphatic amine onto amine density yield. At a concentration of 50% of amine and 50% of isopropanol, EDA, DETA, TETA, and TEPA had attained amine density around 5.12, 4.06, 3.04, and 2.56 mmol/g-ad, respectively. The amine density yield decreases further as the aliphatic amine chain grows longer. The experimental condition for amine functionalization process was fixed at 70% amine, 30% isopropanol, 60 °C for grafting temperature, and 2 h of grafting time for attaining 100% of grafting yield (Dg). The prepared adsorbents were characterized comprehensively in terms of structural and morphology with multiple analytical tools. An adsorptive removal and selectivity of Cu ion by the prepared adsorbent was investigated in a binary metal ion system. The IRP samples with a functional precursor of EDA, the smallest aliphatic amine had given the higher adsorption capacity and selectivity towards Cu ion. The selectivity of IRP samples reduces as the aliphatic amine chain grows longer, EDA to TEPA. However, IRP samples still exhibited remarkably higher selectivity in comparison to the amine immobilized GMA-g-NWF at similar adsorption experimental conditions. This observation indicates that IRP samples possess higher selectivity after incorporation of the ion recognition imprint technique via the radiation crosslinking process.

Sugarcane bagasse (SCB) is a renewable biomass source for cellulose extraction. In the pretreatment, SCB is processed to break down the cellulose-lignin-hemicellulose matrix and isolate components. This work proposes a formic/peroxyformic acid process for extracting cellulose nanocrystals (CNCs) from SCB. Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and solid-state 13C nuclear magnetic resonance (ss- 13C NMR) were employed to evidence the removal of wax, hemicellulose, and lignin from the raw SCB. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) were used for analyzing crystallinity, morphology, and thermal properties. SEM results showed that after lignin removal, the size of purified cellulose fibrils decreased significantly, and the structure of cellulose microfibers became smoother and more apparent. After acid hydrolysis of bleached cellulose microfibers, XRD analysis showed CNCs had the highest crystallinity (70.8 %). In TEM images, rod-like structures of CNCs were measured to be 23 ± 2.7 nm wide and 610 ± 18 nm long. The eco-friendly formic/peroxyformic acid procedure with a chlorine-free bleaching stage produced a white, cellulose-rich solid powder of CNCs

The airways should be considered as a functional unit. Indeed, disorders involving the upper respiratory tract (URT) spread to the lower respiratory tract (LRT). Modern functional anatomy divides URT in three, mutually dependent, junction boxes: i) the ostio-meatal complex (OMC), ii) the spheno-ethmoidal recess (SER), and iii) the rhinopharynx (RP). The first is the most interesting as it joins the anterior paranasal sinuses with the nose. The correct ventilation and the effective mucociliary clearance of these three pathophysiologic junction boxes condition the healthy physiology of the entire respiratory system. The OMC, SER and RP obstruction is the first pathogenic step in the inflammatory cascade of the rhino-sinusal-pharyngeal disorders. The inflammation of the respiratory mucosa is the main pathogenic factor for airway obstruction that may be generically defined as a heterogeneous group of pathologies. Moreover, the bacterial biofilms are an important local cause of recurrent diseases: they are a strategic modality of survival set up by bacteria and the main cause of their resistance to systemic antibiotic therapy.

The 211At-labeled compound, 4-[211At]astato-l-phenylalanine, is one of the most promising amino acid derivatives for use in targeted alpha therapy (TAT) for various cancers. Electrophilic demetallation of a stannyl precursor is the most widely used approach for labeling biomolecules with 211At. However, the low acid-resistance of the stannyl precursor necessitates the use of an N- and C-terminus-protected precursor, which results in a low overall radiochemical yield (RCY) due to the multiple synthetic steps involved. In this study, a deprotected organosilyl compound, 4-triethylsilyl-l-phenylalanine, was employed for the direct synthesis of astatinated phenylalanines. 211At was separately recovered from the irradiated 209Bi target using chloroform (CHCl3) and N-chlorosuccinimide-methanol (NCS-MeOH) solution. The RCYs of 4-[211At]astato-l-phenylalanine obtained from the triethylsilyl precursor with the use of 211At, isolated in CHCl3 and NCS-MeOH solution, were 75% and 64% respectively. In both cases, the retention time of the 4-[211At]astato-l-phenylalanine was found to be about 20 min, which showed reasonable correlation with the retention time of non-radioactive 4-halo-l-phenylalanines (4-chloro-, 4-bromo-, and 4-iodo-l-phenylalanine). The one-step reaction examined in this study involved mild reaction conditions (70 °C) and a short time (10 min) compared to the other currently reported procedures for astatination. Electrophilic desilylation was found to be very effective for the labeling of aromatic amino acids with 211At.

Inhalation of asbestos increases the risk of lung cancer and pulmonary fibrosis. It is difficult to directly assess the distribution and content of inhaled particles in lung tissue sections. The purpose of this study is to employ an in-air micro particle induced X-ray emission (in-air micro-PIXE) system for assessment of the spatial distribution and content of asbestos and other metals in lung tissue. A proton ion-microbeam from this system was applied to irradiate lung tissue of patients with or without asbestosis, tumor tissue from both groups, and asbestos fibers (in vitro). The content of each element composing asbestos and those of other metals were calculated and their distribution was assessed from the characteristic X-ray pattern for each element obtained after irradiation. This in-air micro-PIXE system could identify the location of asbestos bodies composed of Si, Mg, and Fe in lung tissue sections. Macrophage and lymphocytes accumulated in that area. This new system also revealed deposits of titanium, nickel, and cobalt in the lung tissues, in addition to asbestos bodies. The Si and Fe content were higher in lungs with asbestosis than in lungs without asbestosis or in tumor tissue. Analysis of asbestos fibers composed of chrysotile, crocidolite, and amosite showed that the ratios of Si, Fe, and Mg corresponded with those for the chemical structures. In-air micro-PIXE analysis is useful for assessing the distribution and quantities of asbestos bodies and also other metals in lung tissue comparing to immune-related cell localizations, and is also useful for analysis of standard asbestos fibers.

(1) Background: Deferoxamine B (DFO) is the most widely used chelator for labeling of zirconium-89 (89Zr) to monoclonal antibody (mAb). Despite the remarkable developments of the clinical 89Zr-immuno-PET, chemical species and stability constants of the Zr-DFO complexes remain controversial. The aim of this study was to re-evaluate their stability constants by identifying species of Zr-DFO complexes and demonstrate that the stability constants can estimate radiochemical yield (RCY) and chelator-to-antibody ratio (CAR). (2) Methods: Zr-DFO species were determined by UV and ESI-MS spectroscopy. Stability constants and speciation of the Zr-DFO complex were redetermined by potentiometric titration. Complexation inhibition of Zr-DFO by residual impurities was investigated by competition titration. (3) Results: Unknown species, ZrHqDFO2, were successfully detected by nano-ESI-Q-MS analysis. We revealed that a dominant specie under radiolabeling condition (pH 7) was ZrHDFO, and its stability constant (logβ111) was 49.1 ± 0.3. Competition titration revealed that residual oxalate inhibits Zr-DFO complex formation. RCYs in different oxalate concentration (0.1 and 0.04 mol/L) were estimated to be 86% and >99%, which was in good agreement with reported results (87%, 97%). (4) Conclusion: This study succeeded in obtaining accurate stability constants of Zr-DFO complexes and estimating RCY and CAR from accurate stability constants established in this study.