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Photoluminescence (PL) properties of Er2O3 specimens were examined by using visible lasers (532 nm and 635 nm) and a UV LED light source (365 nm) to investigate the applicability for irradiation damage monitoring of materials in fusion reactors. Both in the laser induced and UV light induced PL spectra, green (510–590 nm) and red (630–725 nm) luminescence was observed. In the spectrum measurements on specimens with different crystallinities, it was confirmed that an intensity of the red luminescence weakened significantly compared with that of the green luminescence in an Er2O3 specimen with a lower crystallinity. The results indicate that the PL measurements of Er2O3 materials could be applicable for the irradiation damage monitoring in fusion reactors. The luminescence property of ion beam irradiated Er2O3 showed that information of irradiation damages could be kept up to ∼ 300 ℃ and almost recovered at 700 ℃. Based on the obtained luminescence properties, positions in a fusion reactor where Er2O3 materials could be used as irradiation damage sensors are proposed. Changes in PL spectra at high temperatures up to ∼ 400 ℃ indicate the possibility that the Er2O3 materials might be applicable also for temperature monitoring of in-vessel components during reactor maintenance periods.

The electrical conductivity of the α-Al2O3 layer formed on FeCrAl alloy APMT (Fe-21Cr-5Al-3Mo) in air atmosphere at 1273 K and 1373 K was measured in a temperature range between room temperature and 1073 K. Low electrical conductivity of the α-Al2O3 layer was clarified in the measurement temperature range. Low electrical conductivity of the ZrO2 layer formed on the Zr metal in air atmosphere at 873 K was also measured. Numerical simulation was performed with three-dimensional thermo-fluid code to clarify the reduction of magnetohydrodynamic (MHD) pressure drop with the electrical insulating α-Al2O3 and ZrO2 layers in liquid blankets of magnetic confinement fusion reactors. The MHD pressure drop is significantly reduced when the four inner surfaces of the duct are electrically insulated by the oxide layers. The electrical insulation of the three inner surfaces is also effective to reduce the MHD pressure drop when the magnetic field is parallel to the conductive wall of the flow duct. However, the MHD pressure drop is induced in the three-surface insulation duct when the magnetic field makes an angle with the conductive wall of the duct.

Climate change and increasing food production due to population growth are global challenges that need immediate attention. The introduction of renewable energy to mitigate climate change and the requirement of adequate land to increase food production are generally mutually exclusive. However, an agrivoltaic system generates renewable electricity and produces agricultural products from a common piece of land, thus increasing the land productivity. In addition, this system contributes to local production, thus reducing the CO2 emissions from logistics. Photovoltaic arrays in previous studies were designed by calculating the irradiance in W/m2, even in recent studies. A careful design of the farmland's illumination must be developed for effective agriculture. The simulations must be scaled based on photosynthetic photon flux density rather than irradiance commonly applied in photovoltaic technology simulations.This study focused on the photosynthetic photon flux density and employed an all-climate solar spectrum model to calculate the photosynthetic photon flux density accurately on farmland partially shaded by solar panels and supporting tubes. This study described an algorithm for estimating the photosynthetic photon flux density values under solar panels. The calculated data were validated using the photosynthetic photon flux density sensors. To calculate the photosynthetic photon flux density under the solar panels, it is essential to weigh the direct and diffused components shaded by the solar panels separately because they have different spectrums. A method to quantify the shading was explored here by solar panels and their supporting tubes for the direct and diffused component as the sun moves. The calculation formula was established by defining the sun's moves and the positions of solar panels and their supporting tubes in terms of elevation and azimuth angles from the observation point.It was found that the waveform based on the calculation formula for the photosynthetic photon flux density under the solar panels reproduced the same tendency as the measured photosynthetic photon flux density. To evaluate this trend numerically, the measured and calculated photosynthetic photon flux densities were compared using the standard residuals. Generally, the similarity of the two values is confirmed by a standard residual value between −3 and 3. The result of this study showed that the standard residual values were negative in more frequencies except for the zero photosynthetic photon flux density at night. This indicates that the calculated photosynthetic photon flux density tends to be higher than the measured photosynthetic photon flux density. The peak frequency of the standard residuals was between −6 and −3. This difference probably occurred because the established calculation formula targets the shading provided by the solar panels and supporting tubes but does not cover the shading provided by the other system structures. The calculation formula enables farmers to evaluate the economic efficiency of the system before introducing it using measured solar irradiation data at the target farmlands by introducing published neighborhood solar irradiation data and considering, in advance, measures to avoid the effects of shading on agricultural production. The next study will be to improve the accuracy of the calculation formula by increasing the number of days and develop a method that leads to the best practices of agricultural production and solar power generation by introducing the system.

Climate change and increasing food demand are global issues that require immediate attention. The agrivoltaic system, which involves installing solar panels above farmland, can simultaneously solve climate and food issues. However, current systems tend to reduce agricultural production and delay the harvest period due to shading by the solar panels. A delayed harvest period impacts the income of farmers who wish to sell produce at specific times. Incorporating a model that calculates the amount of electricity generated by solar irradiation, this study establishes a model to estimate the correct start date of cultivation for solar panel covered crops to ensure the correct harvest date and determines the expected income of farmers by calculating agricultural production and power generation. Using taro cultivation in Miyazaki Prefecture as a case study, the model estimated that the start date of cultivation should be brought forward by 23 days to ensure the ideal harvest period and agricultural production. This would prevent an opportunity loss of USD 16,000 per year for a farm area of 10,000 m2. Furthermore, an additional income of USD 142,000 per year can be expected by adjusting shading rates for the cultivation and non-cultivation periods.

Functional ceramic coatings have been investigated for several decades to mitigate tritium permeation through structural materials in a fusion reactor blanket. For the establishment of a liquid blanket system, the coatings require not only tritium permeation reduction but also the tolerance to irradiation damage induced by neutrons and corrosion by liquid tritium breeders. In this study, deuterium permeation measurements under exposure to liquid lithium–lead were performed for a heavy-ion-irradiated zirconium oxide coating sample to elucidate the synergy of irradiation and corrosion on hydrogen isotope permeation. The irradiated coating decreased the deuterium permeation flux under lithium–lead exposure by more than two orders of magnitude in comparison with the unirradiated one. Each activation energy of permeation and diffusion of the coating sample was larger than that of the unirradiated one at around 450 °C and decreased to the level of the unirradiated one at 600 °C. The results indicated that the voids formed by ion irradiation aggregated in grain boundaries of the coating, resulting in an increase in the energy barrier of diffusion at low temperatures and then a decrease due to the defect recovery at high temperatures. Besides, a corrosion product layer formed on the coating during lithium–lead exposure increased the energy barrier of solution. The synergy of irradiation and corrosion on permeation was developed at lower temperatures before the defect recovery.

Ceramic coatings have been developed for nearly half a century to mitigate tritium leakage through steels and corrosion of the components in fusion reactor blanket systems. In recent years, irradiation effects of ceramic coatings on their characteristics and functions have been elucidated through heavy-ion irradiation tests. However, most of analytical methods used in these studies were destructive and time-consuming. In this study, yttrium oxide coatings were fabricated by radio-frequency magnetron sputtering, and the electrical impedance measurements were conducted for the coatings to develop a convenient approach for understanding of irradiation effects. The conductivity obtained from Nyquist plots showed lower values for the undamaged sample than for the damaged ones below 350 °C, while the relationship of the conductivity was reversed at 350 °C and higher temperatures. The ac conductivity of the undamaged sample showed a frequency dependence from 200 °C to 550 °C; however, that of the damaged ones did not show at 300 °C and lower temperatures and indicated a tendency similar to undamaged one above 300 °C. These tendencies of the conductivity at low temperatures were attributed to the partial recovery of the irradiation damage, while the remaining irradiation defects and/or irradiation-induced grain growth affected the electrical properties at higher temperatures. The electrical impedance spectroscopy methods have a potential to detect the influence of irradiation on the coating.

Deuterium permeation through a fusion-relevant ferritic steel F82H with and without erbium oxide coatings under γ-ray irradiation has been investigated in a temperature range from 300 to 700 °C. The deuterium permeation flux through F82H sample increased by γ-ray irradiation at lower temperatures below 450 °C. The irradiation effect increased with dose rate, and the percentage of the permeation flux gain might be several percent under the dose rate of a few Gy s‒1. Temperature of the F82H sample surface rose by about 0.5 °C depending on the dose rate, and so the γ-ray irradiation effect is mainly attributed to γ-heating. On the other hand, at higher temperature above 500 °C, no appreciable change of the deuterium permeation was observed. Similarly, the deuterium permeation flux through erbium oxide coated samples increased under γ-ray irradiation at lower temperatures (350‒450 °C), but no appreciable change of permeation flux through coatings was observed at higher temperatures (600‒700 °C). The coating surface temperature increased at lower sample temperatures by γ-heating. Keywords: Tritium, Permeation, γ-ray, Irradiation, F82H, Erbium oxide

Activation analysis of impurities was performed on a test specimen of the reference low-activation vanadium alloy NIFS-HEAT-2 (V-4Cr-4Ti) which has been irradiated in Japan Materials Testing Reactor (JMTR) ~16 years before. Since the radioactive nuclides from V, Cr and Ti are produced with short half-lives, intense peaks of 60Co (T1/2 = 5.27 years) were dominant in the measured gamma-ray energy spectra and peaks of 94Nb (2.03 × 104 years) were also observed. The concentrations were evaluated to be 0.41 wppm and 0.71 wppm respectively from comparison with results of radioactivity calculation using the FISPACT-2005 code. In the analysis, detection of 108mAg (418 years), which would have a considerable influence on the material recycling after the usage in a fusion reactor, was intense motivation. Although the peaks of 108mAg has not been detected, the concentration of Ag was estimated to be

Traumatic visceral arteriovenous fistulae are rare and pose a diagnostic and therapeutic challenge. We present the case of a 20-year-old male who sustained multiple gunshot wounds to the abdomen, injuring the inferior vena cava, duodenum, stomach, and small bowel. The patient was taken emergently to the operating room for repair of his injuries, which required primary small bowel repair, duodenal repair, and inferior vena cava ligation due to exigent hemorrhage. At the initial operation there was a normal pulse in the superior mesenteric artery at the base of the small bowel mesentery, with no evidence of hematoma or thrill in the small bowel mesentery. The patient was subsequently returned to the operating room several times for bowel exploration and abdominal wall closure with mesh. Ten days after his initial injury, the patient was noted to have an abdominal bruit on physical exam. Arteriography demonstrated a fistula between the proximal superior mesenteric artery and vein with significant portal hypertension. The patient underwent surgical repair of the superior mesenteric artery and vein with closure of the fistula. The patient had no further complications and was discharged from the hospital 1 month later, after abdominal wall skin grafting, in good condition. The patient remains in good health 12 months later. Continued vigilance and careful physical examination are important in the identification of delayed vascular injuries and allow timely treatment and avoidance of untoward long-term sequelae. [ABSTRACT FROM AUTHOR]

Yttrium oxide coatings were fabricated on reduced activation ferritic/martensitic steels by metal organic decomposition with a dip-coating technique, and their deuterium permeation behaviors were investigated. The microstructure of the coatings varied with heat-treatment temperature: amorphous at 670ºC (amorphous coating) and crystallized at 700ºC (crystallized coating). Deuterium permeation flux of the amorphous coating was lower than the uncoated steel by a factor of 5 at 500ºC, while that of the crystallized coating was lower by a factor of around 100 at 400‒550ºC. The permeation fluxes of both coatings were drastically decreased during the measurements at higher temperatures by a factor of up to 790 for the amorphous coating and 1000 for the crystallized one, indicating a microstructure modification occurred by an effect of test temperature with hydrogen flux. Temperature dependence of deuterium diffusivity in the coatings suggests that the decrease of the permeation flux has been derived from a decrease of the diffusivity. Characteristic permeation behaviors were observed with different annealing conditions; however, they can be interpreted using the permeation mechanism clarified in the previous erbium oxide coating studies.

Lead lithium alloy (Pb-17Li) is one of the candidate tritium breeders of fusion reactors. Lead bismuth eutectic alloy (LBE) is one of the candidate materials for the coolant of fast reactors and the target of accelerator driven systems. The functional layers such as an anti-corrosion layer and a tritium permeation barrier have been developed to be applied in these liquid metal systems. Zirconium oxide (ZrO2) are considered to be the candidate material of the functional layers due to its excellent chemical stability. The online monitoring of oxygen potential in the liquid metals is essential technology. The development of in-situ analysis technique for the layer properties in the liquid metals at high temperature is important issue. The purpose of the present study is to develop the on-line monitoring system for the oxygen potential and the layer properties both by the solid electrolyte (SE) oxygen sensor and the electrochemical impedance spectroscopy (EIS). The YSZ type SE sensor and the ZrO2/Zr specimen for the EIS were simultaneously immersed to liquid Pb at 698-898K. The responses of the oxygen sensor and the EIS were successfully obtained, and these signals indicated that the ZrO2 oxide layer is thermodynamically stable in liquid Pb. The EIS response was evaluated based on some equivalent circuit models as the oxide layer had a lot of horizontal cracks in its structure. The influence of the cracks on the capacitance is larger than that on the electrical resistance, when the covering ratio of the cracks in the layer is low. The influence on the electrical resistant becomes larger when the ratio is close to 100%.

Background: Air travel associated with venous thromboembolism has recently achieved public awareness due to intense media coverage. The interest has focused on deep vein thrombosis (DVT) of the lower limbs with pulmonary embolism. The World Health Organization (WHO) is planning several international multicenter trials to study the problem and, if it exists, try to find a means for prevention.Methods: This is a case presentation of acute venous thromboembolism of the upper limbs associated with long-haul flights. Five patients were admitted to Straub Hospital in Honolulu after 5 to 10 hours flight.Results: Patient 1 had a previous shoulder injury with DVT; patient 2 had chronic atrial fibrillation; patients 3 and 5 had clavicular fractures; and patient 4 had a subclavian vein compression.Conclusion: It is not possible to draw any conclusions about the association between air flights and subclavian vein thrombosis from this small retrospective case study. Our objective was to indicate the possibility of such a relationship. [ABSTRACT FROM AUTHOR]

The surface of a Fe-Ni-Cr Alloy (SUS316L) plate was electrochemically nitrided in molten LiF-KF salt including Li3N at 873K. The crystal structure changed from fcc structure to bct structure with nitrogen introduction. The Nitrogen diffusion layers were predominately formed at nitrogen concentration of 23 at%. The nitriding process drastically also changed its magnetic property from non-magnetic to ferromagnetic. The magnetic field of 20 kOe saturated the magnetic moment with its magnetization of 81 emu/g at 10K. The anisotropic magnetization is ascertained. Based on CrN formation and Cr extraction from the original Fe-Ni-Cr system, the induced ferromagnetism was discussed.

Intracellular circadian clocks, composed of clock genes that act in transcription-translation feedback loops, drive global rhythmic expression of the mammalian transcriptome and allow an organism to anticipate to the momentum of the day. Using a novel clock-perturbing peptide, we established a pivotal role for casein kinase (CK)-2-mediated circadian BMAL1-Ser90 phosphorylation (BMAL1-P) in regulating central and peripheral core clocks. Subsequent analysis of the underlying mechanism showed a novel role of CRY as a repressor for protein kinase. Co-immunoprecipitation experiments and real-time monitoring of protein-protein interactions revealed that CRY-mediated periodic binding of CK2β to BMAL1 inhibits BMAL1-Ser90 phosphorylation by CK2α. The FAD binding domain of CRY1, two C-terminal BMAL1 domains, and particularly BMAL1-Lys537 acetylation/deacetylation by CLOCK/SIRT1, were shown to be critical for CRY-mediated BMAL1-CK2β binding. Reciprocally, BMAL1-Ser90 phosphorylation is prerequisite for BMAL1-Lys537 acetylation. We propose a dual negative-feedback model in which a CRY-dependent CK2-driven posttranslational BMAL1-P-BMAL1 loop is an integral part of the core clock oscillator.

Dysfunction of circadian clocks exacerbates various diseases, in part likely due to impaired stress resistance. It is unclear how circadian clock system responds toward critical stresses, to evoke life-protective adaptation. We identified a reactive oxygen species (ROS), H2O2 -responsive circadian pathway in mammals. Near-lethal doses of ROS-induced critical oxidative stress (cOS) at the branch point of life and death resets circadian clocks, synergistically evoking protective responses for cell survival. The cOS-triggered clock resetting and pro-survival responses are mediated by transcription factor, central clock-regulatory BMAL1 and heat shock stress-responsive (HSR) HSF1. Casein kinase II (CK2) -mediated phosphorylation regulates dimerization and function of BMAL1 and HSF1 to control the cOS-evoked responses. The core cOS-responsive transcriptome includes CK2-regulated crosstalk between the circadian, HSR, NF-kappa-B-mediated anti-apoptotic, and Nrf2-mediated anti-oxidant pathways. This novel circadian-adaptive signaling system likely plays fundamental protective roles in various ROS-inducible disorders, diseases, and death.

Circadian rhythms are the general physiological processes of adaptation to daily environmental changes, such as the temperature cycle. A change in temperature is a resetting cue for mammalian circadian oscillators, which are possibly regulated by the heat shock (HS) pathway. The HS response (HSR) is a universal process that provides protection against stressful conditions, which promote protein-denaturation. Heat shock factor 1 (HSF1) is essential for HSR. In the study presented here, we investigated whether a short-term HS pulse can reset circadian rhythms. Circadian Per2 rhythm and HSF1-mediated gene expression were monitored by a real-time bioluminescence assay for mPer2 promoter-driven luciferase and HS element (HSE; HSF1-binding site)-driven luciferase activity, respectively. By an optimal duration HS pulse (43°C for approximately 30 minutes), circadian Per2 rhythm was observed in the whole mouse fibroblast culture, probably indicating the synchronization of the phases of each cell. This rhythm was preceded by an acute elevation in mPer2 and HSF1-mediated gene expression. Mutations in the two predicted HSE sites adjacent (one of them proximally) to the E-box in the mPer2 promoter dramatically abolished circadian mPer2 rhythm. Circadian Per2 gene/protein expression was not observed in HSF1-deficient cells. These findings demonstrate that HSF1 is essential to the synchronization of circadian rhythms by the HS pulse. Importantly, the interaction between HSF1 and BMAL1:CLOCK heterodimer, a central circadian transcription factor, was observed after the HS pulse. These findings reveal that even a short-term HS pulse can reset circadian rhythms and cause the HSF1-BMAL1:CLOCK interaction, suggesting the pivotal role of crosstalk between the mammalian circadian and HSR systems.

Substitutional doping, involving the replacement of a host with an aliovalent impurity ion, is widely used to attain ambipolar controllability in semiconductors, which is crucial for device application. However, its effectiveness for p-type doping is limited in monovalent cation compounds due to the lack of suitable aliovalent (i.e., zerovalent) impurities. We propose an alternative approach for p- and n-type doping, mediated by the sizes of isovalent alkali metal impurities in Cu(I)-based semiconductors, such as copper nitride with an electron concentration of ∼10 15 cm -3 . Doping of isovalent Li with a smaller size to interstitial positions improves n-type conductivity, and electron concentration is controllable in the range of 10 15 to 10 18 cm -3 . In contrast, larger isovalent Cs and Rb impurities facilitate p-type conversion, resulting in a hole concentration controllability of 10 14 to 10 17 cm -3 . First-principles calculations indicate that Li is placed as an interstitial impurity acting as a shallow donor in conjunction with the formation of a neutral impurity on Cu defects. As the impurity size increases beyond the capacity of the vacant space, the formation of multiple acceptor-type Cu vacancies is enhanced owing to the repulsion between host Cu + and Cs + /Rb + impurities. Consequently, the Cs or Rb impurity is located at the sites of the N accompanied by six neighboring Cu vacancies, forming acceptor defect complexes. This size-dependent isovalent impurity doping scheme opens up an alternative avenue for advancement in optoelectronic devices using monovalent cation-based semiconductors.

In Japan, the traditional method for measuring plasma aldosterone concentration (PAC) was radioimmunoassay (RIA), which had several challenges, including poor traceability of certified reference materials and reduced detection sensitivity at low concentrations. To overcome these issues, a chemiluminescent enzyme immunoassay (CLEIA) for PAC measurement was introduced in April 2021 and the Japan Endocrine Society published new guidelines for primary aldosteronism (PA). This study aimed to evaluate the impact of the transition from RIA to CLEIA for PAC measurement on PA diagnosis. Data from 190 patients admitted to the Second Department of Internal Medicine, University of the Ryukyus Hospital, between April 2012 and March 2021 were analyzed. Patients who were diagnosed with PA underwent adrenal venous sampling. The PAC measured by RIA (PAC(RIA)) was converted to the estimated PAC measured by CLEIA (ePAC(CLEIA)) using a conversion formula. The present study evaluated the discordance rates in diagnoses based on screening (SC), captopril challenge test (CCT), saline infusion test (SIT), and diagnosis of PA between results judged by PAC(RIA) according to the previous guidelines and those judged by ePAC(CLEIA) according to the new guidelines. The results revealed discordant diagnosis rates of 6.4% for SC and 10.1% for CCT, with no discordance for SIT. The discordant diagnosis rate for PA was 3.7%. Our study reveals the challenges in establishing appropriate diagnostic criteria for PA using PAC(CLEIA) and highlights the demand for further research on provisionally positive categories.

Aims: Paraoxonase 1 (PON1) binds to high-density lipoprotein (HDL) and protects against atherosclerosis. However, the relationship between functional PON1 Q192R polymorphism, which is associated with the hydrolysis of paraoxon (POXase activity) and atherosclerotic cardiovascular disease (ASCVD), remains controversial. As the effect of PON1 Q192R polymorphism on the HDL function is unclear, we investigated the relationship between this polymorphism and the cholesterol efflux capacity (CEC), one of the biological functions of HDL, in association with the PON1 activity., Methods: The relationship between PON1 Q192R polymorphisms and CEC was investigated retrospectively in 150 subjects without ASCVD (50 with the PON1 Q/Q genotype, 50 with the Q/R genotype, and 50 with the R/R genotype) who participated in a health screening program. The POXase and arylesterase (AREase: hydrolysis of aromatic esters) activities were used as measures of the PON1 activity., Results: The AREase activity was positively correlated with CEC independent of the HDL cholesterol levels. When stratified by the PON1 Q192R genotype, the POXase activity was also positively correlated with CEC independent of HDL cholesterol. PON1 Q192R R/R genotype carriers had a lower CEC than Q/Q or Q/R genotype carriers, despite having a higher POXase activity. Moreover, in a multiple regression analysis, the PON1 Q192R genotype was associated with the degree of CEC, independent of the HDL cholesterol and POXase activity., Conclusions: The PON1 Q192R R allele is associated with reduced CEC in Japanese people without ASCVD. Further studies on the impact of this association on the severity of atherosclerosis and ASCVD development are thus called for.

Phytotoxic compounds isolated and identified from different plants have the ability to use as plant-based herbicides. Phytotoxic chemicals may be essential to weed management and environmental protection in order to reduce the indiscriminate use of synthetic pesticides. It has been reported that Elaeocarpus floribundus plant possesses phytotoxic compounds. The leaf extracts of this species demonstrated significant growth inhibition against the tested plants (dicot plant lettuce and plant monocot timothy) and inhibition was dose- and species-dependent pattern. Two phytotoxic compounds were separated using different purifications methods and identified as compounds 1 and 2 . All phytotoxic compounds displayed potent growth limitation against the tested species (cress). The compound concentrations needed for the inhibition of 50% growth (IC 50 value) of tested species ranged from 1.06 to 8.53  µ M (micromolar). Findings of this research suggest that these compounds might be responsible for the phytotoxicity of Elaeocarpus floribundus plant. The results of this study may be helpful for the development of natural herbicide to control weeds., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2024 Kawsar Hossen et al.)