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Low-frequency (LF) noise measurements are compared for Schottky-gate AlGaN/GaN heterostructure planar and fin field-effect transistors (FinFETs) as functions of gate voltage and measuring temperature. The noise of each device type is consistent with a carrier number fluctuation model. Similar effective defect-energy Eo distributions are derived for each of the two device architectures from measurements of excess drain-voltage noise-power spectral density vs temperature from 80 to 380 K. Defect- and/or impurity-related peaks are observed in the inferred energy distributions for Eo < 0.2 eV, Eo ≈ 0.45 eV, and Eo > 0.6 eV. Significant contributions to the LF noise are inferred for nitrogen vacancies and ON and FeGa impurity complexes. Ga dangling bonds at fin interfaces with gate metal are likely candidates for enhanced noise observed in FinFETs, relative to planar devices. Reducing the concentrations of these defects and impurity complexes should reduce the LF noise and enhance the performance, reliability, and radiation tolerance of GaN-based high electron mobility transistors. [ABSTRACT FROM AUTHOR]

We evaluated whether veterans with Gulf War illness (VGWI) report greater ionizing radiation adverse effects (RadAEs) than controls; whether radiation-sensitivity is tied to reported chemical-sensitivity; and whether environmental exposures are apparent risk factors for reported RadAEs (rRadAEs). 81 participants (41 VGWI, 40 controls) rated exposure to, and rRadAEs from, four radiation types. The relations of RadAE-propensity (defined as the ratio of rRadAEs to summed radiation exposures) to Gulf War illness (GWI) presence and severity, and to reported chemical-sensitivity were assessed. Ordinal logistic regression evaluated exposure prediction of RadAE-propensity in the full sample, in VGWI, and stratified by age and chemical-sensitivity. RadAE-propensity was increased in VGWI (vs. controls) and related to GWI severity (p

Radiosensitivity to low and medium doses of X-ray radiation and the ability to induce a radiation adaptive response (RAR) of lymphocytes during in vitro irradiation of peripheral blood of patients with cancer were studied. The criterion for cytogenetic damage was the frequency of micronuclei (MN) in cytochalasin-blocked binucleate lymphocytes in culture. It was found that the spontaneous level of cytogenetic damage in the lymphocytes of patients was 2.6 times higher than in healthy volunteers, and there was also significant interindividual variability in values compared to the control cohort. There were no differences in mean values for radiosensitivity to low and medium doses of X-ray between the study groups. There was no correlation between the spontaneous level of MN in lymphocytes and the radiosensitivity of individuals in both groups. RAR was induced with the same frequency and to the same extent in lymphocytes from both patients and healthy individuals. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) has a low survival rate and limited treatment options. Concurrent chemoradiotherapy is considered beneficial to improve tumor control, but the low drug bioavailability at tumor site and the low radiation tolerance of surrounding healthy organs greatly limits its effectiveness. Lipiodol, a natural drug carrier used in clinical transarterial chemoembolization, has shown potential as a radiosensitizer due to its high Z element iodine composition. Thus, this study aims to repurpose lipiodol as a sensitizer to simultaneously enhance chemo- and radiotherapy for PDAC. To this end, a stable lipiodol emulsion (IOE) loaded with gemcitabine is designed using clinically approved surfactants. At in vivo level, IOE demonstrates better radiotherapeutic effect than existing nanoradiosensitizers and enhanced drug bioavailability over free drug, leading to significant tumor inhibition and improved survival rates under concurrent chemo-radiotherapy. This may due to the sustained drug release, homogenous spatial distribution, and long-term retention ability of IOE in solid PDAC tumor. Furthermore, to better understand the functioning mechanism of drug-loaded IOE, in vitro study is conducted to reveal the ROS- and DNA damage-related therapeutic pathways. Lastly, a comprehensive toxicity assessment also proves the good biocompatibility and safety of as-prepared IOE. This study offers a clinically feasible sensitizer for simultaneous chemoradiotherapy and holds potential for other types of cancer treatment in clinics. [Display omitted] • Lipiodol emulsion (IOE) functions as a simultaneous radiochemosensitizer for PDAC. • IOE increases drug bioavailability, retentivity and diffusion in solid tumor. • Oxidative stress and DNA damage-based therapeutic mechanism is verified. • IOE possesses good biosafety. [ABSTRACT FROM AUTHOR]

BACKGROUND: The diamondback moth (DBM) (Plutella xylostella) causes large losses to global crop production. Conventional insecticides are losing effectiveness due to resistance. Consequently, there is a growing interest in sustainable control methods like entomopathogenic fungi (EPF) in Integrated Pest Management. However, the field efficacy of fungi varies due to environmental influences. In this study, a group of 50 Beauveria strains sourced from different locations were characterized by genotype and phenotype with respect to their conidial production, temperature and UV‐B radiation tolerance, and virulence against DBM. RESULTS: Phylogenetic analysis revealed two distinct species: Beauveria bassiana (84%) and B. pseudobassiana (16%). Most strains showed optimal growth between 25 °C and 28 °C, with germination severely affected at 10 °C and 33 °C. Notably, 44% displayed high resistance to UV‐B radiation (5.94 kJ m−2), with germination rates between 60.9% and 88.1%. Geographical origin showed no correlation with temperature or UV radiation tolerance. In virulence experiments, 52% of strains caused mortality rates exceeding 80% in DBM second instars at 7 days after exposure to a 4 mL conidial suspension (107 conidia/mL). CONCLUSION: Survival under environmental conditions is crucial for EPF‐based commercial products against DBM. Results suggest strain tolerance to environmental stressors is more tied to specific micro‐climatic factors than geographical origin. Each strain exhibited unique characteristics; for example, the most virulent strain (#29) was highly UV‐sensitive. Therefore, characterizing diverse strains provides essential genotypic and phenotypic insights, which are fundamental for understanding their role as biocontrol agents while facilitating efficient biopesticide product development and uptake. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Drosophila suzukii is a pest native to Southeast Asia that causes significant economic losses to soft fruit crops. Phytosanitary irradiation is a promising treatment for D. suzukii hosts; yet an internationally recognized irradiation protocol is lacking. To fulfil specific requirements for proposing an irradiation treatment for D. suzukii, naturally infested blueberries and cherries containing a total of 37,489 late pupae were irradiated with a maximum absorbed dose of 80 Gy. Infested hosts containing a total of 9578 late pupae were considered unirradiated controls. Prevention of egg laying by females that emerged from treated pupae was considered the treatment endpoint. The fecundity and egg viability of females that emerged from treated pupae mated with their siblings were evaluated using blueberries. While females from unirradiated pupae laid a total of 43,142 eggs, no egg was laid by females that emerged from irradiated pupae. In addition, 1-day-old adults were irradiated with nominal doses of 20 and 72 Gy to evaluate whether egg laying could be prevented in flies emerging before the irradiation treatment. Females irradiated with 72 Gy laid eggs that did not hatch. Our findings suggest the minimum absorbed dose of 80 Gy as a phytosanitary irradiation treatment against D. suzukii and may support its inclusion as a treatment option in the annex of the International Standard for Phytosanitary Measures 28 (ISPM 28). [ABSTRACT FROM AUTHOR]

The total ionizing dose effect of Mg-doped p-GaN gate stack have been investigated in this Letter on the whole gate voltage swing arranging from −1.3 to +1.5V. Additionally, two distinct kinds of mechanisms of trap effects have been extracted, which are response to in turns three phases of mechanism, voltage-controlled, coexist of voltage/current-controlled and current-controlled. It indicates that the fast traps are located at p-GaN/AlGaN interface (ET is about 0.295–0.333 eV), while the slow traps are located at AlGaN/GaN interface (ET is about 0.393–0.485 eV). They both have increasing trap density and broader range under γ-ray radiation. When the applied gate voltage rises to about 1 V, the effects of slow trap states are significantly weakened. However, the fast trap states barely change. Finally, the complete transition into current-controlled mode is observed at 1.5 V. What is more, p-GaN/AlGaN interface traps are further extracted near the gate turn-on voltage under γ-ray irradiation rather than the voltage-controlled mechanism of weak accumulation at the threshold voltage. Under the 600 krad γ-ray irradiation, the holes trap at p-GaN/AlGaN interface is identified with the trap activation energy ET at about 0.28–0.3 eV and trap density of about 4 × 1012 cm−2 eV−1. The increase in trap induces the reduction of gate current. In summary, this work can further our understanding of radiation tolerance and trapping effects of p-GaN gate high-electron mobility transistors for power switches, especially in regard to forward conduction status. [ABSTRACT FROM AUTHOR]

Metal halide perovskites (MHPs) are low‐temperature processable hybrid semiconductor materials with exceptional performances that are revolutionizing the field of optoelectronic devices. Despite their great potential, commercial deployment is hindered by MHPs lack of stability and durability, mainly attributed to ion migration and chemical interactions with the electrodes. To address these issues, 2D layered MHPs are investigated as possible device interlayers or active material substitutes. Here, the 2D perovskite (PEA)2PbBr4 is considered that is recently discussed as promising candidate for X‐ray direct detection. While the increased resilience of (PEA)2PbBr4 radiation detectors has already been reported, the physical mechanisms responsible for such improvement compared to 3D perovskites are not still fully understood. To unravel the charge transport process in (PEA)2PbBr4 crystals thought to underly the device better performance, an investigation technique is adapted previously used on highly resistive inorganic semiconductors, called photo induced current transient spectroscopy (PICTS). It is demonstrated that PICTS can reliably detect three trap states (T1, T2, and T3), and that their evolution upon X‐ray exposure can explain (PEA)2PbBr4 superior radiation tolerance and reduced aging effects. Overall, the results provide essential insights into the electrical characteristics of 2D perovskites and their potential application as reliable direct X‐ray detectors. [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusion Ultra‐high dose rate irradiation (≥40 Gy/s, FLASH) has been shown to reduce normal tissue toxicity, while maintaining tumor control compared to conventional dose‐rate radiotherapy. The radiolytic oxygen (O2) depletion (ROD) resulting from FLASH has been proposed to explain the normal tissue protection effect; however, in vivo experiments have not confirmed that FLASH induced global tissue hypoxia. Nonetheless, the experiments reported are based on volume‐averaged measurement, which have inherent limitations in detecting microscopic phenomena, including the potential preservation of stem cells niches due to local FLASH‐induced O2 depletion. Computational modeling offers a complementary approach to understand the ROD caused by FLASH at the microscopic level.We developed a comprehensive model to describe the spatial and temporal dynamics of O2 consumption and transport in response to irradiation in vivo. The change of oxygen enhancement ratio (OER) was used to quantify and investigate the FLASH effect as a function of physiological and radiation parameters at microscopic scale.We considered time‐dependent O2 supply and consumption in a 3D cylindrical geometry, incorporating blood flow linking the O2 concentration ([O2]) in the capillary to that within the tissue through the Hill equation, radial and axial diffusion of O2, metabolic and zero‐order radiolytic O2 consumption, and a pulsed radiation structure. Time‐evolved distributions of [O2] were obtained by numerically solving perfusion‐diffusion equations. The model enables the computation of dynamic O2 distribution and the relative change of OER (δROD) under various physiological and radiation conditions in vivo.Initial [O2] level and the subsequent changes during irradiation determined δROD distribution, which strongly depends on physiological parameters, i.e., intercapillary spacing, ultimately determining the tissue area with enhanced radioresistance. We observed that the δROD/FLASH effect is affected by and sensitive to the interplay effect among physiological and radiation parameters. It renders that the FLASH effect can be tissue environment dependent. The saturation of FLASH normal tissue protection upon dose and dose rate was shown. Beyond ∼60 Gy/s, no significant decrease in radiosensitivity within tissue region was observed. In turn, for a given dose rate, the change of radiosensitivity became saturated after a certain dose level. Pulse structures with the same dose and instantaneous dose rate but with different delivery times were shown to have distinguishable δROD thus tissue sparing, suggesting the average dose rate could be a metric assessing the FLASH effect and demonstrating the capability of our model to support experimental findings.On a macroscopic scale, the modeling results align with the experimental findings in terms of dose and dose rate thresholds, and it also indicates that pulse structure can vary the FLASH effect. At the microscopic level, this model enables us to examine the spatially resolved FLASH effect based on physiological and irradiation parameters. Our model thus provides a complementary approach to experimental methods for understanding the underlying mechanism of FLASH radiotherapy. Our results show that physiological conditions can potentially determine the FLASH efficacy in tissue protection. The FLASH effect may be observed under optimal combination of physiological parameters, not limited to radiation conditions alone. [ABSTRACT FROM AUTHOR]

The use of entomopathogenic fungi (EF) is a promising alternative for the control of Rhipicephalus microplus, an important tick affecting cattle globally. This study aimed to evaluate the effect of ultraviolet irradiation (UV) exposure on the percentage of conidia germination and number of colony-forming units of eight strains of Metarhizium anisopliae (MaV55, MaV35, MaV31, MaV25, MaV13, Ma08, MaV05, and MaV02). The UV (UV-A and UV-A+B) irradiation was carried out with an ultraviolet radiation emission lamp. The conidia of each strain were exposed to the UV irradiation treatments for 3 h. MaV25, MaV08, MaV05, MaV13, and MaV31 showed higher tolerance to UV-A radiation exposure, as assessed by conidia germination. UV-A+B radiation decreased the germination percentage of all the M. anisopliae strains. The eight evaluated strains showed good tolerance to UV-A radiation, as assessed by the development of colony-forming units (CFU). UV-A+B radiation did not significantly affect (p > 0.05) the count of the CFU of six of the M. anisopliae strains evaluated (MaV35, MaV13, MaV08, MaV05, MaV31, and MaV02). The novel findings of the UV-tolerant M. anisopliae strains may potentially improve the effectiveness of EF under environmental conditions. Integral research under real tropical conditions is advised to evaluate the effectiveness of the EF strains. [ABSTRACT FROM AUTHOR]

In recent years, revolutionary improvements in the properties of certain FCC metals have been achieved by increasing the proportion of twin-related, highly symmetric grain boundaries. Various thermomechanical routes of grain boundary engineering (GBE) processing have been employed to enhance the fraction of low ΣCSL grain boundaries, thereby improving the radiation tolerance of many polycrystalline materials. This improvement is due to symmetric twin boundaries acting as effective sinks for defects caused by radiation, thus enhancing the material's performance. In this study, the LPBF AlSi10Mg alloy was post-processed via the KOBO extrusion method. Subsequently, the samples were subjected to irradiation with Ar+ ions at an ion fluence of 5 × 1017 cm−2. The microstructures of the samples were thoroughly investigated using electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM). The results showed that KOBO processing led to the formation of an ultrafine-grained microstructure with a mean grain size of 0.8 µm. Moreover, it was revealed that the microstructure of the KOBO-processed sample exhibited an increased fraction of low-ΣCSL boundaries. Specifically, the fraction of Σ11 boundaries increased from approximately 2% to 8%. Post-irradiation microstructural analysis revealed improved radiation tolerance in the KOBO-processed sample, indicating a beneficial influence of the increased grain boundary fraction and low-ΣCSL boundary fraction on the irradiation resistance of the AlSi10Mg alloy. This research provides valuable insights for the development of customized microstructures with enhanced radiation tolerance, which has significant implications for the advancement of materials in nuclear and aerospace applications. [ABSTRACT FROM AUTHOR]

Esophageal cancer (ESCA) is one of the most fatal gastrointestinal cancers worldwide. ESCA is often diagnosed in its middle or late stages since the first symptoms are not identifiable. The use of radiotherapy, either alone or in conjunction with surgical intervention and chemotherapy, is essential to achieve a positive prognosis. Radiotherapy is an essential component of treatment for ESCA. Autophagy, a prevalent biological phenomenon, has a twofold impact on the incidence, progression, and treatment response of malignant tumors. This review explores the intricate mechanisms by which autophagy modulates radiation sensitivity in ESCA, including its effects on DNA repair, oxidative stress responses, and apoptosis. We provide a comprehensive analysis of recent advancements in the modulation of autophagy, focusing on the use of autophagy inhibitors and inducers to enhance radiotherapy efficacy. We discuss how autophagy inhibitors such as chloroquine and 3-methyladenine can overcome radiation resistance by blocking autophagic processes, while autophagy inducers like rapamycin can sensitize cancer cells to radiotherapy-induced cell death. Additionally, we examine the potential therapeutic benefits of combining autophagy regulation with existing treatment modalities, offering new strategies to improve patient outcomes. This review highlights the critical role of autophagy in ESCA and underscores the promise of autophagy-targeted therapies in enhancing the effectiveness of radiotherapy, thereby providing a novel avenue for overcoming treatment resistance and improving prognosis in ESCA patients. [ABSTRACT FROM AUTHOR]

Strong gene flow from outcrossing relatives tends to blur species boundaries, while divergent ecological selection can counteract gene flow. To better understand how these two forces affect the maintenance of species boundaries, we focused on a species complex including a rare species, maple-leaf oak (Quercus acerifolia), which is found in only four disjunct ridges in Arkansas. Its limited range and geographic proximity to co-occurring close relatives create the possibility for genetic swamping. In this study, we gathered genome-wide single nucleotide polymorphisms (SNPs) using restriction-site-associated DNA sequencing (RADseq) from 190 samples of Q. acerifolia and three of its close relatives, Q. shumardii , Q. buckleyi , and Q. rubra. We found that Q. shumardii and Q. acerifolia are reciprocally monophyletic with low support, suggesting incomplete lineage sorting, introgression between Q. shumardii and Q. acerifolia , or both. Analyses that model allele distributions demonstrate that admixture contributes strongly to this pattern. Populations of Q. acerifolia experience gene flow from Q. shumardii and Q. rubra , but we found evidence that divergent selection is likely maintaining species boundaries: 1) ex situ collections of Q. acerifolia have a higher proportion of hybrids compared to the mature trees of the wild populations, suggesting ecological selection against hybrids at the seed/seedling stage; 2) ecological traits co-vary with genomic composition; and 3) Q. acerifolia shows genetic differentiation at loci hypothesized to influence tolerance of radiation, drought, and high temperature. Our findings strongly suggest that in maple-leaf oak, selection results in higher divergence at regions of the genome despite gene flow from close relatives. [ABSTRACT FROM AUTHOR]

A Monte Carlo simulation was used to assess the performance of a collimated hollow X-ray microbeam for subcellular cytoplasm irradiation. A high-Z coaxial collimation structure with an inner core for nucleus shielding was investigated. Two key performances, the extraction efficiency (cytoplasm dose per unit incident fluence) and the dose contrast (cytoplasm-to-nucleus dose ratio), were evaluated regarding the influences of the material, geometry and physical arrangements of the collimator, target dish and incident beam source. Simulation results demonstrate that a gold coaxial structure with a practical collimation geometry of a 1-mm length, 10-μm inner diameter and 200-μm outer diameter, with the top exit closely attached (with a minimized air gap) to the bottom of a cell dish with a 3-μm thick Mylar film is recommended for cytoplasm irradiation of adherent mammalian cells. For a synchrotron source in the energy range < 10 keV, a dose contrast of approximately 100 can be achieved. For a bremsstrahlung source <30-kV tube voltage, a dose contrast of approximately 50–100 can still be achieved. General principles are summarized with further explanations of the performance of the hollow X-ray microbeam. [ABSTRACT FROM AUTHOR]

While ferroptosis shows promise in anti-cancer strategy, the molecular mechanisms behind this process remain poorly understood. Our research aims to highlight the regulation of radiotherapy-induced ferroptosis in non-small cell lung cancer (NSCLC) via the NRF2/PHKG2 axis-mediated mechanism. To identify ferroptosis-associated genes associated with radioresistance in NSCLC, this study employed high-throughput transcriptome sequencing and Lasso risk regression analysis. Clinical samples were analyzed to confirm PHKG2 expression changes before and after radiotherapy. The study further examined ferritinophagy-related factors, intracellular iron levels, mitochondrial function, and ferroptosis in NSCLC cells undergoing radiation exposure to explore the effect of PHKG2 on radiosensitivity or radioresistance. The research also demonstrated the transcriptional inhibition of PHKG2 by NRF2 and created in situ transplantation tumor models of NSCLC to examine the role of NRF2/PHKG2 axis in NSCLC radiosensitivity and resistance in vivo. The Lasso risk regression model that incorporated ferroptosis-associated genes effectively predicted the prognosis of patients with NSCLC. Radiotherapy-sensitive tissues exhibited an increased expression of PHKG2. Overexpression of PHKG2 led to elevated intracellular iron levels by promoting ferritinophagy and increased mitochondrial stress-dependent ferroptosis induced by radiotherapy. PHKG2 transcription repression was achieved through NRF2. The FAGs-Lasso risk regression model can accurately predict the prognosis of NSCLC patients. Targeting Nrf2 upregulates the expression of PHKG2 and reverses radiotherapy resistance in NSCLC by promoting iron autophagy and inducing mitochondrial dysfunction, thereby increasing radiotherapy sensitivity. [ABSTRACT FROM AUTHOR]

This study explored the fascinating field of high-performance nanoscale metallic multilayer composites, focusing on their magnetic, optical, and radiation tolerance properties, as well as their thermal and electrical properties. In general, nanoscale metallic multilayer composites have a wide range of outstanding properties, which differ greatly from those observed in monolithic films. Their exceptional properties are primarily due to the large number of interfaces and nanoscale layer thicknesses. Through a comprehensive review of existing literature and experimental data, this paper highlights the remarkable performance enhancements achieved by the precise control of layer thicknesses and interfaces in these composites. Furthermore, it will discuss the underlying mechanisms responsible for their exceptional properties and provide insights into future research directions in this rapidly evolving field. Many studies have investigated these materials, focusing on their magnetic, mechanical, optical, or radiation-tolerance properties. This paper summarizes the findings in each area, including a description of the general attributes, the adopted synthesis methods, and the most common characterization techniques used. The paper also covers related experimental data, as well as existing and promising applications. The paper also covers other phenomena of interest, such as thermal stability studies, self-propagating reactions, and the progression from nanomultilayers to amorphous and/or crystalline alloys. Finally, the paper discusses challenges and future perspectives relating to nanomaterials. Overall, this paper is a valuable resource for researchers and engineers interested in harnessing the full potential of nanoscale metallic multilayer composites for advanced technological applications. [ABSTRACT FROM AUTHOR]

Exploring efficient and low‐toxicity radiosensitizers to break through the bottleneck of radiation tolerance, immunosuppression and poor prognosis remains one of the critical developmental challenges in radiotherapy. Nanoheterojunctions, due to their unique physicochemical properties, have demonstrated excellent radiosensitization effects in radiation energy deposition and in lifting tumor radiotherapy inhibition. Herein, they doped selenium (Se) into prussian blue (PB) to construct a nano‐heterojunction (Se@PB), which could promote the increase of Fe2+/Fe3+ ratio and conversion of Se to a high valence state with Se introduction. The Fe2+‐Se‐Fe3+ electron transfer chain accelerates the rate of electron transfer on the surface of the nanoparticles, which in turn endows it with efficient X‐ray energy transfer and electron transport capability, and enhances radiotherapy physical sensitivity. Furthermore, Se@PB induces glutathione (GSH) depletion and Fe2+ accumulation through pro‐Fenton reaction, thereby disturbs the redox balance in tumor cells and enhances biochemical sensitivity of radiotherapy. As an excellent radiosensitizer, Se@PB effectively enhances X‐ray induced mitochondrial dysfunction and DNA damage, thereby promotes cell apoptosis and synergistic cervical cancer radiotherapy. This study elucidates the radiosensitization mechanism of Se‐doped nanoheterojunction from the perspective of the electron transfer chain and biochemistry reaction, which provides an efficient and low‐toxic strategy in radiotherapy. [ABSTRACT FROM AUTHOR]

The Japan Aerospace Exploration Agency (JAXA) is planning a Space photovoltaics Demonstration eXperiment (SDX) to reveal the tolerance to the space environment of the next-generation solar cells. One of the next-generation solar cells mounted on SDX is a perovskite solar cell (PSC), which is cost-effective and has the potential for high specific power and radiation tolerance. It is necessary to clarify the long-term stability to analyze the characteristics of PSCs in orbit because SDX will be stored for months before and after launch. Therefore, we conducted three storage tests (in air, nitrogen, and low pressure) using encapsulated PSCs. Their performance was evaluated by Light I–V, Dark I–V, and EQE measurements. As a result, almost no degradation was observed at EOL (after 400 days) under all storage conditions. We found that the encapsulated PSCs mounted on SDX are highly stable. We also found that the slight degradation of P max within 4 % was due to an increase in series resistance. • The Japan Aerospace Exploration Agency is developing perovskite solar cells for use in space. • Perovskite solar cells have an issue with long-term stability; it is still unknown how stable they are in orbit in the subject mission. • We researched the long-term stability (in air, nitrogen, and low pressure) and degradation trend of perovskite solar cells in space. • We found they have high stability after 400 days of storage even though in air, and can be applied to our mission. [ABSTRACT FROM AUTHOR]

The first mirror is the front-end optic component that reflects light emitted from the plasma to the diagnostic system in fusion plasmas. Silicon carbide (SiC), known for its relatively high mechanical strength and radiation tolerance, has been selected as the substrate material for the first mirror in the ITER divertor vacuum ultraviolet (VUV) spectrometer. To measure the reflectivity of the ellipse cylindrical SiC mirror to be manufactured, a device for reflectivity measurement in the VUV wavelength range was developed. First, the reflectivity of a sample SiC mirror (15 mm diameter × 10 mm thick) was measured across the ITER-required incidence angles, and the results are reported in this study. A hollow cathode lamp with helium gas was used as the VUV light source in the wavelength range of 23–60 nm, and a dedicated VUV spectrometer to select specific wavelengths was developed. The spectrometer utilized laminar-type replica diffraction gratings (Shimadzu 30-006) and two back-illuminated charge-coupled devices (BI-CCD, Andor DO 940P-BEN) for the grating and detector, respectively. A cropping technique with aperture was employed to precisely localize the VUV light's reflection onto the SiC mirror surface. The experimentally measured reflectivity values of SiC at the required incidence angles of VUV light were compared with theoretically calculated reflectivity curves. The oxidation layer (SiO2) formed on the SiC surface and the incidence angle of VUV light to the BI-CCD chip (E2V) would be the factors affecting the accuracy of the reflectivity. [ABSTRACT FROM AUTHOR]

Nano-satellites, which are following the CubeSat standard have established for demanding industrial and scientific applications with critical requirements on reliability and radiation tolerance. The employment of commercial off-the-shelf components enables a state-of-the-art performance but requires extensive testing to avoid and mitigate malefunctions due to the space environment. The CubeSat mission CLIMB is representative for future missions with a complex payload, a high power budget and a harsh radiation exposure. For this reason, a comprehensive irradiation study of its on-board-computer was done. The total ionizing dose damage of 50 krad was evaluated at a 60 Co source. As a consequence of this test, specific components were exchanged before performing single event effect studies at the synchrotron accelerator MedAustron. A board-level test revealed that the majority of effects concern the central micro controller wherefore was followed by a component-level test. Those irradiation tests make use of a pencil beam to map the device under test, which provides additional information to localize effects - by the timestamp - at the expense of an increased irradiation time compared to a homogeneous exposure. In this paper, we summarize the major findings of the test campaign and mitigation means and present a procedure for single event effect studies at medical accelerators. [ABSTRACT FROM AUTHOR]

For the development of the remote elemental analysis method in a radiation environment based on the laser-induced breakdown spectroscopy (LIBS), the radiation effects on the laser oscillation properties of the single crystal (SC) Nd:YAG microchip laser (MCL) were investigated and compared with those of ceramic Nd:YAG MCL. The laser oscillation properties were measured under gamma ray irradiation as a function of dose rate. The effects on the SC MCL properties were very small compared to those on the ceramics, indicating minimal radiation effects on the LIBS signal when using SC MCL. Pulse energy and oscillating build-up time (BUT) were measured for cumulative dose exceeding 1400 kGy. The pulse energy remained stable under irradiation. The BUT also remained stable, demonstrating negligible optical loss accumulation that could affect laser properties even at the demonstrated cumulative dose. The results indicate that the effects of dose rate and cumulative dose on SC MCL laser properties are minimal. The SC MCL was then integrated into the LIBS system, and the gadolinium signal was successfully measured at a dose rate of 5 kGy/hr. These findings highlight the radiation tolerance of SC MCL for remote LIBS applications in harsh radiation environments. [ABSTRACT FROM AUTHOR]

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Abstract Drosophila suzukii is a pest native to Southeast Asia that causes significant economic losses to soft fruit crops. Phytosanitary irradiation is a promising treatment for D. suzukii hosts; yet an internationally recognized irradiation protocol is lacking. To fulfil specific requirements for proposing an irradiation treatment for D. suzukii, naturally infested blueberries and cherries containing a total of 37,489 late pupae were irradiated with a maximum absorbed dose of 80 Gy. Infested hosts containing a total of 9578 late pupae were considered unirradiated controls. Prevention of egg laying by females that emerged from treated pupae was considered the treatment endpoint. The fecundity and egg viability of females that emerged from treated pupae mated with their siblings were evaluated using blueberries. While females from unirradiated pupae laid a total of 43,142 eggs, no egg was laid by females that emerged from irradiated pupae. In addition, 1-day-old adults were irradiated with nominal doses of 20 and 72 Gy to evaluate whether egg laying could be prevented in flies emerging before the irradiation treatment. Females irradiated with 72 Gy laid eggs that did not hatch. Our findings suggest the minimum absorbed dose of 80 Gy as a phytosanitary irradiation treatment against D. suzukii and may support its inclusion as a treatment option in the annex of the International Standard for Phytosanitary Measures 28 (ISPM 28).

In memory semiconductors such as a static random access memory (SRAM), a common problem is soft errors under radiation environment. These soft errors cause bit flips, which are referred to as single event upsets (SEUs). Some radiation-hardened SRAM cells such as a Quatro SRAM, we-Quatro SRAM, and DICE SRAM cells have been reported for years. However, these designs have the disadvantage of taking up more area than a conventional 6T SRAM cell. Thus, we propose a radiation-hardened SRAM cell design that we named capacitor-static random access memory (C-SRAM) without area overhead. The C-SRAM is formed by simply adding a capacitor to the conventional 6T SRAM. It was designed to mitigate the radiation effect using the conservation law of electrical charge. Moreover, it has the same cell size as the conventional 6T SRAM cell. Its static noise margins (SNMs), which are indicators of operational stability, are equal to the conventional 6T SRAM values of 530 mV, 220 mV, and 860 mV in hold, read, and write modes, respectively. The results of the SEU simulation test showed that it had 4.761 times better flipping tolerance than the conventional 6T SRAM with a charge value of 247.494 fC. In addition, irradiation experiments also confirmed that the C-SRAM cell was more tolerant than the 6T SRAM cell. The conventional 6T SRAM and C-SRAM were fabricated using a standard 0.18 μm CMOS process.

Zirconate pyrochlores have been extensively studied as candidate waste forms for the immobilization of actinide wastes due to their flexible crystal chemistry, excellent structural stability, and exceptional radiation tolerance. Herein, we report the synthesis of a series of compounds Eu2Zr2–xO7–2x (x = 0–1, step = 0.125) using a co‐precipitation route to form solid solutions between the two end members, Eu2Zr2O7 pyrochlore and Eu2ZrO5 defect fluorite. It is important to understand the pyrochlore to defect fluorite transformation as a function of Zr/Ln molar ratio. The structural investigation by x‐ray diffraction has shown the increasing cation disorder and corresponding structural transitions from the ordered pyrochlore to disordered pyrochlore, then to defect fluorite. While diffuse reflectance spectroscopy provides similar optical absorption features reflecting the presence of Eu(III) ion, Raman spectroscopy has revealed more details on the phase transition and short‐range structures. This work highlights the structural flexibility in zirconate materials as potential nuclear waste forms for the immobilization of actinide‐rich waste streams, especially suitable for the separated minor actinides. [ABSTRACT FROM AUTHOR]

Chalcogenide thin films that undergo reversible phase changes show promise for use in next-generation nanophotonics, microelectronics, and other emerging technologies. One of the many studied compounds, Ge2Sb2Te5, has demonstrated several useful properties and performance characteristics. However, the efficacy of benchmark Ge2Sb2Te5 is restricted by amorphous phase thermal stability below ∼150 °C, limiting its potential use in high-temperature applications. In response, previous studies have added a fourth species (e.g., C) to sputter-deposited Ge2Sb2Te5, demonstrating improved thermal stability. Our current research confirms reported thermal stability enhancements and assesses the effects of carbon on crystalline phase radiation response. Through in situ transmission electron microscope irradiation studies, we examine the effect of C addition on the amorphization behavior of initially cubic and trigonal polycrystalline films irradiated using 2.8 MeV Au to various doses up to 1 × 1015 cm−2. It was found that increased C content reduces radiation tolerance of both cubic and trigonal phases. [ABSTRACT FROM AUTHOR]

PRMT5 is a widely expressed arginine methyltransferase that regulates processes involved in tumor cell proliferation and survival. In the study described here, we investigated whether PRMT5 provides a target for tumor radiosensitization. Knockdown of PRMT5 using siRNA enhanced the radiosensitivity of a panel of cell lines corresponding to tumor types typically treated with radiotherapy. To extend these studies to an experimental therapeutic setting, the PRMT5 inhibitor LLY-283 was used. Exposure of the tumor cell lines to LLY-283 decreased PRMT5 activity and enhanced their radiosensitivity. This increase in radiosensitivity was accompanied by an inhibition of DNA double-strand break repair as determined by γH2AX foci and neutral comet analyses. For a normal fibroblast cell line, although LLY-283 reduced PRMT5 activity, it had no effect on their radiosensitivity. Transcriptome analysis of U251 cells showed that LLY-283 treatment reduced the expression of genes and altered the mRNA splicing pattern of genes involved in the DNA damage response. Subcutaneous xenografts were then used to evaluate the in vivo response to LLY-283 and radiation. Treatment of mice with LLY-283 decreased tumor PRMT5 activity and significantly enhanced the radiation-induced growth delay. These results suggest that PRMT5 is a tumor selective target for radiosensitization. [ABSTRACT FROM AUTHOR]

Radiotherapy (RT) treatment is an important strategy for the management of non-small cell lung cancer (NSCLC). Local recurrence amongst patients with late-stage NSCLC remains a challenge. The loss of PTEN has been associated with radio-resistance. This study aimed to examine the efficacy of RT combined with ataxia telangiectasia-mutated Rad3-related (ATR) inhibition using Ceralasertib in phosphatase and tensin homolog (PTEN)-depleted NSCLC cells and to assess early inflammatory responses indicative of radiation pneumonitis (RP) after combined-modality treatment. Small hairpin RNA (shRNA) transfections were used to generate H460 and A549 PTEN-depleted models. Ceralasertib was evaluated as a single agent and in combination with RT in vitro and in vivo. Histological staining was used to assess immune cell infiltration in pneumonitis-prone C3H/NeJ mice. Here, we report that the inhibition of ATR in combination with RT caused a significant reduction in PTEN-depleted NSCLC cells, with delayed DNA repair and reduced cell viability, as shown by an increase in cells in Sub G1. Combination treatment in vivo significantly inhibited H460 PTEN-depleted tumour growth in comparison to H460 non-targeting PTEN-expressing (NT) cell-line-derived xenografts (CDXs). Additionally, there was no significant increase in infiltrating macrophages or neutrophils except at 4 weeks, whereby combination treatment significantly increased macrophage levels relative to RT alone. Overall, our study demonstrates that ceralasertib and RT combined preferentially sensitises PTEN-depleted NSCLC models in vitro and in vivo, with no impact on early inflammatory response indicative of RP. These findings provide a rationale for evaluating ATR inhibition in combination with RT in NSCLC patients with PTEN mutations. [ABSTRACT FROM AUTHOR]

In this work, the heavy-ion irradiation responses of MgO-Nd 2 Zr 2 O 7 (M-NZO) composite ceramics used for inert matrix fuel were experimentally investigated. And the micro and macro radiation damage of M-NZO samples was systemically unveiled after 5 MeV Xe20+ irradiation and quantified by two exposure units, displacements per atom (dpa) and phonons per atom (ppa). The newly ppa represent the number of phonon modes available in the radiated material, which are high relative to thermal properties and the resulting morphological fragmentation after irradiation. In detail, MgO phase mostly retains its pristine structure without extensive amorphization irradiated at high dpa values, meanwhile, Nd 2 Zr 2 O 7 phase also presents satisfactory radiation resistance through the distinctive order-disorder structural transformations that alleviate radiation-induced strain. Besides, MgO grains with lower ppa value dissipate ions energy more efficiently than Nd 2 Zr 2 O 7 , and exhibit higher radiation tolerance at macroscopic morphological scale. Overall, M-NZO composite ceramics have good radiation tolerance under heavy-ion bombardment, in which the lower ppa value and higher thermal conductivity of MgO make itself possess superior resistance to irradiation-induced damage than Nd 2 Zr 2 O 7. [ABSTRACT FROM AUTHOR]

Background: Glioblastoma are highly malignant type of primary brain tumors. Treatment for glioblastoma multiforme (GBM) generally involves surgery combined with chemotherapy and radiotherapy. However, the development of tumoral chemo- and radioresistance induces complexities in clinical practice. Multiple signaling pathways are known to be involved in radiation-induced cell survival. However, the role of alpha-thalassemia X-linked mutant retardation syndrome (ATRX), a chromatin remodeling protein, in GBM radioresistance remains unclear. Methods: In the present study, the ATRX mutation rate in patients with glioma was obtained from The Cancer Genome Atlas, while its expression analyzed using bioinformatics. Datasets were also obtained from the Gene Expression Omnibus, and ATRX expression levels following irradiation of GBM were determined. The effects of ATRX on radiosensitivity were investigated using a knockdown assays. Results: The present study demonstrated that the ATRX mutation rate in patients with GBM was significantly lower than that in patients with low-grade glioma, and that patients harboring an ATRX mutation exhibited a prolonged survival, compared with to those harboring the wild-type gene. Single-cell RNA sequencing demonstrated that ATRX counts increased 2 days after irradiation, with ATRX expression levels also increasing in U-251MG radioresistant cells. Moreover, the results of in vitro irradiation assays revealed that ATRX expression was increased in U-251MG cells, while ATRX knockdown was associated with increased levels of radiosensitivity. Conclusions: High ATRX expression levels in primary GBM may contribute to high levels of radioresistance. Thus ATRX is a potential target for overcoming the radioresistance in GBM. [ABSTRACT FROM AUTHOR]

Background: Artemis deficiency is an autosomal recessive disorder characterized by a combined immunodeficiency with increased cellular radiosensitivity. In this review, the clinical and genetic characteristics of 15 patients with DCLRE1C variants are presented. Methods: The demographic, clinical, immunologic, and genetic characteristics of patients with confirmed DCLRE1C variants diagnosed between 2013 and 2023 were collected retrospectively. Three patients were evaluated for radiosensitivity by the Comet assay, compared with age‐ and sex‐matched healthy control. Results: Seven patients who had severe infections in the first 6 months of life were diagnosed with T‐B‐NK+ SCID (severe combined immunodeficiency). Among them, four individuals underwent transplantation, and one of those died due to post‐transplant complications in early life. Eight patients had hypomorphic variants. Half of them were awaiting a suitable donor, while the other half had already undergone transplantation. The majority of patients were born into a consanguineous family (93.3%). Most patients had recurrent sinopulmonary infections (73.3%), and one patient had no other infection than an acute respiratory infection before diagnosis. Two patients (13.3%) had autoimmunity in the form of autoimmune hemolytic anemia. Growth retardation was observed in only one patient (6.6%), and no malignancy was detected in the surviving 11 patients during the median (IQR) of 21.5 (12–45) months of follow‐up. Three patients who had novel variants exhibited increased radiosensitivity and compromised DNA repair, providing a potential vulnerability to malignant transformation. Conclusion: Early diagnosis, radiation avoidance, and careful preparation for transplantation contribute to minimizing complications, enhancing life expectancy, and improving the patient's quality of life. [ABSTRACT FROM AUTHOR]

Amorphous interfacial complexions are particularly resistant to radiation damage and have been primarily studied in alloys with good glass-forming ability, yet recent reports suggest that these features can form even in immiscible alloys such as Cu-Ta under irradiation. In this study, the mechanisms of damage production and annihilation due to primary knock-on atom collisions are investigated for amorphous interphase and grain boundaries in a Cu-Ta alloy using atomistic simulations. Amorphous complexions, in particular amorphous interphase complexions that separate Cu and Ta grains, result in less residual defect damage than their ordered counterparts. Stemming from the nanophase chemical separation in this alloy, the amorphous complexions exhibit a highly heterogeneous distribution of atomic excess volume, as compared to a good glass former like Cu-Zr. Complexion thickness, a tunable structural descriptor, plays a vital role in damage resistance. Thicker interfacial films are more damage-tolerant because they alter the defect production rate due to differences in intrinsic displacement threshold energies during the collision cascade. Overall, the findings of this work highlight the importance of interfacial engineering in enhancing the properties of materials operating in radiation-prone environments and the promise of amorphous complexions as particularly radiation damage-tolerant microstructural features. [ABSTRACT FROM AUTHOR]

Objective: This narrative review aimed to compile and summarize clinically relevant literature in radiation therapy and to discuss the potential in radioresistant and radiosensitive head and neck squamous cell carcinoma (HNSCC). Methods and Materials: Google Scholar, PubMed, and the Cochrane Library were retrieved using combined key words such as "radiotherapy" and "head and neck cancer." Search strings additionally queried were "radioresistant," "radiosensitive," "head and neck region," "squamous cell carcinoma," in combination with Boolean operators 'AND' and 'OR.' Subsequently, the resulting publications were included for review of the full text. Results: Radiotherapeutic responses currently in clinical observation referred to HNSCC scoping were selected into this review. The compiled mechanisms were then detailed concerning on the clinical significance, biological characteristics, and molecular function. Conclusions: Brachytherapy or/and external-beam radiotherapy are crucial for treating HNSCC especially the early stage patients, but in some patients with locally advanced tumors, their outcome with radiation therapy is poor due to obvious radioresistance. The curative effects mainly depend on the response to radiation therapy so an updated review is needed to optimize further applications in HNSCC radiotherapy. [ABSTRACT FROM AUTHOR]

Our study aims to identify the mechanisms involved in regulating the response of Rhodoendron Chrysanthum Pall. (R.chrysanthum) leaves to UV-B exposure; phosphorylated proteomics and metabolomics for phenolic acids and plant hormones were integrated in this study. The results showed that UV-B stress resulted in the accumulation of salicylic acid and the decrease of auxin, jasmonic acid, abscisic acid, cytokinin and gibberellin in R.chrysanthum. The phosphorylated proteins that changed in plant hormone signal transduction pathway and phenolic acid biosynthesis pathway were screened by comprehensive metabonomics and phosphorylated proteomics. In order to construct the regulatory network of R.chrysanthum leaves under UV-B stress, the relationship between plant hormones and phenolic acid compounds was analyzed. It provides a rationale for elucidating the molecular mechanisms of radiation tolerance in plants. [ABSTRACT FROM AUTHOR]

Background: Quantum Dots (QDs) are fluorescent nanoparticles with exceptional optical and optoelectronic properties, finding widespread utility in diverse industrial applications. Presently, chemically synthesized QDs are employed in solar cells, bioimaging, and various technological domains. However, many applications demand QDs with prolonged lifespans under conditions of high-energy radiation. Over the past decade, microbial biosynthesis of nanomaterials has emerged as a sustainable and cost-effective process. In this context, the utilization of extremophile microorganisms for synthesizing QDs with unique properties has recently been reported. Results: In this study, UV-resistant bacteria were isolated from one of the most extreme environments in Antarctica, Union Glacier at the Ellsworth Mountains. Bacterial isolates, identified through 16 S sequencing, belong to the genera Rhodococcus, Pseudarthrobacter, and Arthrobacter. Notably, Rhodococcus sp. (EXRC-4 A-4), Pseudarthrobacter sp. (RC-2-3), and Arthrobacter sp. (EH-1B-1) tolerate UV-C radiation doses ≥ 120 J/m². Isolated UV-resistant bacteria biosynthesized CdS QDs with fluorescence intensities 4 to 8 times higher than those biosynthesized by E. coli, a mesophilic organism tolerating low doses of UV radiation. Transmission electron microscopy (TEM) analysis determined QD sizes ranging from 6 to 23 nm, and Fourier-transform infrared (FTIR) analysis demonstrated the presence of biomolecules. QDs produced by UV-resistant Antarctic bacteria exhibit high photostability after exposure to UV-B radiation, particularly in comparison to those biosynthesized by E. coli. Interestingly, red fluorescence-emitting QDs biosynthesized by Rhodococcus sp. (EXRC-4 A-4) and Arthrobacter sp. (EH-1B-1) increased their fluorescence emission after irradiation. Analysis of methylene blue degradation after exposure to irradiated QDs biosynthesized by UV-resistant bacteria, indicates that the QDs transfer their electrons to O2 for the formation of reactive oxygen species (ROS) at different levels. Conclusions: UV-resistant Antarctic bacteria represent a novel alternative for the sustainable generation of nanostructures with increased radiation tolerance—two characteristics favoring their potential application in technologies requiring continuous exposure to high-energy radiation. [ABSTRACT FROM AUTHOR]

Objective: Radiotherapy (RT) is a cornerstone of the glioblastoma (GBM) treatment. However, the resistance of tumour cells to radiation results in early recurrence. The mechanisms underlying GBM radioresistance remain unclear. Screening for differentially expressed genes (DEGs) related to radiation might be a potential solution to this problem. Method: RT‐associated DEGs were screened based on the RNA sequencing of 15 paired primary and recurrent GBMs. The mRNA and protein expression of candidate genes were validated in RNA sequencing of The Chinese Genome Atlas (CGGA) dataset and 18 cases of GBM samples. The relationship between the candidate gene and radiation was confirmed in irradiated GBM cells. The association of candidate gene with clinical characteristics and survival was investigated in the CGGA and TCGA dataset. Biological function and pathway analysis were explored by gene ontology analysis. The association of the candidate gene with radiosensitivity was verified using cell counting Kit‐8, comet, and colony formation assays in vitro and subcutaneous tumour xenograft experiments in vivo. Results: Gelsolin (GSN) was selected for further study. GSN expression was significant elevated in recurrent GBM and up‐regulated in irradiated GBM cell lines. High expression of GSN was enriched in malignant phenotype of glioma. Moreover, high expression of GSN was associated with poor prognosis. Further investigation demonstrated that GSN‐knockdown (GSN‐KD) combined with RT significantly inhibited cell proliferation and enhanced radiosensitivity in vivo and in vitro. Mechanistically, GSN‐KD could lead to more serious DNA damage and promotes apoptosis after RT. Conclusion: Radiation induced up‐regulated of GSN. GSN‐KD could enhance the radiosensitivity of GBM. [ABSTRACT FROM AUTHOR]

The efficacy of radiotherapy, a cornerstone in the treatment of lung adenocarcinoma (LUAD), is profoundly undermined by radiotolerance. This resistance not only poses a significant clinical challenge but also compromises patient survival rates. Therefore, it is important to explore this mechanism for the treatment of LUAD. Multiple public databases were used for single‐cell RNA sequencing (scRNA‐seq) data. We filtered, normalized and downscaled scRNA‐seq data based on the Seurat package to obtain different cell subpopulations. Subsequently, the ssGSEA algorithm was used to assess the enrichment scores of the different cell subpopulations, and thus screen the cell subpopulations that are most relevant to radiotherapy tolerance based on the Pearson method. Finally, pseudotime analysis was performed, and a preliminary exploration of gene mutations in different cell subpopulations was performed. We identified HIST1H1D+ A549 and PIF1+ A549 as the cell subpopulations related to radiotolerance. The expression levels of cell cycle‐related genes and pathway enrichment scores of these two cell subpopulations increased gradually with the extension of radiation treatment time. Finally, we found that the proportion of TP53 mutations in patients who had received radiotherapy was significantly higher than that in patients who had not received radiotherapy. We identified two cellular subpopulations associated with radiotherapy tolerance, which may shed light on the molecular mechanisms of radiotherapy tolerance in LUAD and provide new clinical perspectives. [ABSTRACT FROM AUTHOR]

Background: Interpatient variation of tumor radiosensitivity is rarely considered during the treatment planning process despite its known significance for the therapeutic outcome. Purpose: To apply our mechanistic biophysical model to investigate the biological robustness of carbon ion radiotherapy (CIRT) against DNA damage repair interference (DDRi) associated patient‐to‐patient variability in radiosensitivity and its potential clinical advantages against conventional radiotherapy approaches. Methods and Materials: The "UNIfied and VERSatile bio response Engine" (UNIVERSE) was extended by carbon ions and its predictions were compared to a panel of in vitro and in vivo data including various endpoints and DDRi settings within clinically relevant dose and linear energy transfer (LET) ranges. The implications of UNIVERSE predictions were then assessed in a clinical patient scenario considering DDRi variance. Results: UNIVERSE tests well against the applied benchmarks. While in vitro survival curves were predicted with an R2 > 0.92, deviations from in vivo RBE data were less than 5.6% The conducted paradigmatic patient plan study implies a markedly reduced significance of DDRi based radiosensitivity variability in CIRT (13% change of D50${{D}_{50}}$ in target) compared to conventional radiotherapy (62%) and that boosting the LET within the target further amplifies this robustness of CIRT (8%). In the case of heightened tumor radiosensitivity, a dose de‐escalation strategy for photons allows a reduction of the maximum effective dose within the normal tissue (NT) from a D2${{D}_2}$ of 2.65 to 1.64 Gy, which lies below the level found for CIRT (D2${{D}_2}$ = 2.41 Gy) for the analyzed plan and parameters. However, even after de‐escalation, the integral effective dose in the NT is found to be substantially higher for conventional radiotherapy in comparison to CIRT (Dmean${{D}_{mean}}$ of 0.75, 0.46, and 0.24 Gy for the conventional plan, its de‐escalation and CIRT, respectively). Conclusions: The framework offers adequate predictions of in vitro and in vivo radiation effects of CIRT while allowing the consideration of DRRi based solely on parameters derived from photon data. The results of the patient planning study underline the potential of CIRT to minimize important sources of interpatient divergence in therapy outcome, especially when combined with techniques that allow to maximize the LET within the tumor. Despite the potential of de‐escalation strategies for conventional radiotherapy to reduce the maximum effective dose in the NT, CIRT appears to remain a more favorable option due to its ability to reduce the integral effective dose within the NT. [ABSTRACT FROM AUTHOR]

Background: We aimed to investigate the effects of PinX1 on non-small cell lung cancer(NSCLC) radiosensitivity and radiotherapy-associated tumor immune microenvironment and its mechanisms. Methods: The effect of PinX1 silencing on radiosensitivity in NSCLC was assessed by colony formation and CCK8 assay, immunofluorescence detection of γ- H2AX and micronucleus assay. Western blot was used to assess the effect of PinX1 silencing on DNA damage repair pathway and cGAS-STING pathway. The nude mouse and Lewis lung cancer mouse model were used to assess the combined efficacy of PinX1 silencing and radiotherapy in vivo. Changes in the tumor immune microenvironment were assessed by flow cytometry for different treatment modalities in the Lewis luuse model. The interaction protein RBM10 was screened by immunoprecipitation-mass spectrometry. Results: Silencing PinX1 enhanced radiosensitivity and activation of the cGAS-STING pathway while attenuating the DNA damage repair pathway. Silencing PinX1 further increases radiotherapy-stimulated CD8+ T cell infiltration and activation, enhances tumor control and improves survival in vivo; Moreover, PinX1 downregulation improves the anti-tumor efficacy of radioimmunotherapy, increases radioimmune-stimulated CD8+ T cell infiltration, and reprograms M2-type macrophages into M1-type macrophages in tumor tissues. The interaction of PinX1 and RBM10 may promote telomere maintenance by assisting telomerase localization to telomeres, thereby inhibiting the immunostimulatory effects of IR. Conclusions: In NSCLC, silencing PinX1 significantly contributed to the radiosensitivity and promoted the efficacy of radioimmunotherapy. Mechanistically, PinX1 may regulate the transport of telomerase to telomeres through interacting with RBM10, which promotes telomere maintenance and DNA stabilization. Our findings reveal that PinX1 is a potential target to enhance the efficacy of radioimmunotherapy in NSCLC patients. [ABSTRACT FROM AUTHOR]

Radiotherapy with bladder preservation is highly acceptable among patients bearing bladder cancer (BCa), but the occurrence of secondary tolerance (ARR) during treatment is one of the important reasons for the failure of clinical radiotherapy. COX-2 has been frequently reported to be highly expressed and associated with radio-resistance in various cancers. In this study, the feasibility of Taraxasterol (Tara) as a radiosensitizer was investigated, and the target effect of Tara on COX-2 and its underlying mechanism were explored. The toxicity of Tara toward BCa cells was detected with the MTT method and cells in response to IR or Tara + IR were compared by clone formation assay. Next, a small RNA interference system (siRNA) was employed to decrease endogenous COX-2 expression in BCa cells, and the stem cell-like features and motion abilities of BCa cells under different treatments were investigated using microsphere formation and transwell chamber assay, respectively. Meanwhile, the expression of a series of inflammation-related molecules and stem cell characteristic molecules was determined by qRT-PCR, western blot and ELISA method. In vivo studies, BCa cells were subcutaneously injected into the right flank of each male mouse. Those mice were then grouped and exposed to different treatment: Tara, IR, IR + Tara and untreated control. The volumes of each tumor were measured every two days and target proteins were detected with immunohistochemical (IHC) staining. The results show that COX-2 decline, due to COX-2 knocking-down or Tara treatment, could greatly enhance BCa cells' radiosensitivity and significantly decrease their migration, invasion and microsphere formation abilities, companied with the reduce of JAK2, phos-STAT3, MMP2 and MMP9 expression. However, Tara could not further reduce the expression of an above molecule of cells in COX-2-deficient BCa cells. Correspondingly, Tara treatment could not further enhance those siCOX-2 BCa cells response to IR. Our data support that Tara can improve the radiosensitivity of BCa cells by targeting COX-2/PGE2. The mechanism may involve regulating STAT3 phosphorylation, DNA damage response protein activation, and expression of MMP2/MMP9. [ABSTRACT FROM AUTHOR]

DNA damage response (DDR) is the principal mechanism regulating genomic stability and cell cycle checkpoint activation by coordinating DNA repair and apoptotic pathways. Ataxia telangiectasia and Rad3-related protein (ATR) play a significant role in the DDR due to its capability to detect a wide spectrum of DNA damage. Therefore, targeting DDR, specifically ATR, is a promising therapeutic strategy in cancer treatment. Furthermore, the inhibition of ATR sensitizes cancer cells to radiotherapy (RT). Herein, we, for the first time, investigated the synergistic effects of Elimusertib (BAY-1895344) as a highly potent selective ATR inhibitor with RT combination in triple-negative breast cancer (TNBC), in vitro. MDA-MB-231 TNBC cells were firstly treated with different concentrations of Elimusertib for 24 h and then exposed to 4 and 8 Gy of X-ray irradiation. After post-irradiation for 72 h, WST-1, Annexin V, cell cycle, acridine orange/propidium iodide, mitochondria staining and western blot analysis were conducted. Our findings showed that 4 Gy irradiation and lower doses (especially 2 and 4 nM) of Elimusertib combination exerted a considerable anticancer activity at 72 h post-irradiation through apoptotic cell death, marked nuclear and mitochondrial damages and the suppression of ATR-Chk1 based DDR mechanism. ATR inhibition by Elimusertib in combination with RT may be a promising new treatment strategy in the treatment of TNBC. However, further experiments should be performed to elucidate the underlying molecular mechanisms of the therapeutic efficacy of this combination treatment and its association with DNS repair mechanisms in TNBC, in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Background: Definitive concurrent chemoradiotherapy (CRT) is the standard of care in advanced stages of head and neck cancer (HNC). With evident increase in survival rate there is also simultaneous increase in toxicity affecting the quality of life. One of the less researched late toxicity is radiation induced brachial plexopathy (RIBP). In this dosimetric study we intent to contour the brachial plexus (BP) as an organ at risk (OAR) and determine the factors that contribute to dose variations to BP, and clinically evaluate the patients for RIBP during follow-up using a questionnaire. Materials and methods: 30 patients with HNC planned for CRT from September 2020 to June 2022 were accrued. Patients were treated to a dose of 6600 cGy with intensity modulated radiotherapy using the simultaneous integrated boost technique. From the dose-volume histogram (DVH) statistics the BP volume, Dmax and other parameters like V66, V60 were assessed and was correlated with respect to primary tumour and nodal stage. Results: On corelation, more than the T stage, the N stage and the primary location had a significant impact on the Dmax. With a median follow-up of 17.9 months, the incidence of RIBP was 6.67%. The 2-year disease free survival and the 2-year overall survival were 53.7% and 59.4%, respectively. Conclusions: In oropharyngeal/hypopharyngeal primaries and in advanced nodal disease, BP receives higher doses contributing to RIBP. Primary tumor and nodal stage also impacted V60 and V66 of BP. Hence, contouring of BP as an OAR becomes imperative, and respecting the DVH parameters is essential. [ABSTRACT FROM AUTHOR]

Identifying new targets for overcoming radioresistance is crucial for improving the efficacy of lung cancer radiotherapy, given that tumor cell resistance is a leading cause of treatment failure. Recent research has spotlighted the significance of Musashi2 (MSI2) in cancer biology. In this study, we first demonstrated that MSI2 plays a key function in regulating the radiosensitivity of lung cancer. The expression of MSI2 is negatively correlated with overall survival in cancer patients, and the knockdown of MSI2 inhibits tumorigenesis and increases radiosensitivity of lung cancer cells. Cellular radiosensitivity, which is closely linked to DNA damage, is influenced by MSI2 interaction with ataxia telangiectasia mutated and Rad3‐related kinase (ATR) and checkpoint kinase 1 (CHK1) post‐irradiation; moreover, knockdown of MSI2 inhibits the ATR‐mediated DNA damage response pathway. RNA‐binding motif protein 17 (RBM17), which is implicated in DNA damage repair, exhibits increased interaction with MSI2 post‐irradiation. We found that knockdown of RBM17 disrupted the interaction between MSI2 and ATR post‐irradiation and increased the radiosensitivity of lung cancer cells. Furthermore, we revealed the potential mechanism of MSI2 recruitment into the nucleus with the assistance of RBM17 to activate ATR to promote radioresistance. This study provides novel insights into the potential application of MSI2 as a new target in lung cancer radiotherapy. [ABSTRACT FROM AUTHOR]

Radiosensitivity differs in humans and possibly in closely related nonhuman primates. The reasons for variation in radiosensitivity are not well known. In an earlier study, we examined gene expression (GE) pre-radiation in peripheral blood among male (n = 62) and female (n = 60) rhesus macaques (n = 122), which did or did not survive (up to 60 days) after whole-body exposure of 7.0 Gy (LD66/60). Eight genes (CHD5, CHI3L1, DYSF, EPX, IGF2BP1, LCN2, MBOAT4, SLC22A4) revealed significant associations with survival. Access to a second rhesus macaque cohort (males = 40, females = 23, total n = 63) irradiated with 5.8–7.2 Gy (LD29-50/60) and some treated with gamma-tocotrienol (GT3, a radiation countermeasure) allowed us to validate these gene expression changes independently. Total RNA was isolated from whole blood samples and examined by quantitative RT-PCR on a 96-well format. cycle threshold (Ct)-values normalized to 18S rRNA were analyzed for their association with survival. Regardless of the species-specific TaqMan assay, similar results were obtained. Two genes (CHD5 and CHI3L1) out of eight revealed a significant association with survival in the second cohort, while only CHD5 (involved in DNA damage response and proliferation control) showed mean gene expression changes in the same direction for both cohorts. No expected association of CHD5 GE with dose, treatment, or sex could be established. Instead, we observed significant associations for those comparisons comprising pre-exposure samples with CHD5 Ct values ≤ 11 (total n = 17). CHD5 Ct values ≤ 11 in these comparisons were mainly associated with increased frequencies (61-100%) of non-survivors, a trend which depending on the sample numbers, reached significance (P = 0.03) in males and, accordingly, in females. This was also reflected by a logistic regression model including all available samples from both cohorts comprising CHD5 measurements (n = 104, odds ratio 1.38, 95% CI 1.07–1.79, P = 0.01). However, this association was driven by males (odds ratio 1.62, 95% CI 1.10–2.38, P = 0.01) and CHD5 Ct values ≤ 11 since removing low CHD5 Ct values from this model, converted to insignificance (P = 0.19). A second male subcohort comprising high CHD5 Ct values ≥ 14.4 in both cohorts (n = 5) appeared associated with survival. Removing these high CHD5 Ct values converted the model borderline significant (P = 0.051). Based on the probability function of the receiver operating characteristics (ROC) curves, 8 (12.3%) and 5 (7.7%) from 65 pre-exposure RNA measurements in males, death and survival could be predicted with a negative and positive predictive value ranging between 85–100%. An associated odds ratio reflected a 62% elevated risk for dying or surviving per unit change (Ct-value) in gene expression, considering the before-mentioned CHD5 thresholds in RNA copy numbers. In conclusion, we identified two subsets of male animals characterized by increased (Ct values ≤ 11) and decreased (Ct values ≥ 14.4) CHD5 GE copy numbers before radiation exposure, which independently of the cohort, radiation exposure or treatment appeared to predict the death or survival in males. [ABSTRACT FROM AUTHOR]

Single-phase concentrated solid-solution alloys (CSAs) have exhibited excellent mechanical and radiation tolerance properties, making them potential candidate materials for nuclear applications. These excellent properties are closely related to dislocation movements, which depend on the stacking fault energies (SFEs). In CSAs, SFEs show large fluctuations due to variations in the local atomic environments in the vicinity of the stacking faults. In this work, first-principle calculations were performed to investigate the origin of the fluctuations in the SFEs of the widely studied CSA, NiCoCr, which show a very wide distribution from about −200 mJ/m2 to 60 mJ/m2. Compared to the common understanding that only atoms in close proximity to the stacking fault influence the SFEs in pure metals and dilute alloys, charge redistribution can be observed in several nearby planes of the stacking fault in NiCoCr, indicating that atoms several atomic layers away from stacking fault also contribute to the SFEs. Our analysis shows that Cr plays a major role in the large fluctuation in the SFEs of NiCoCr based on both electronic and magnetic responses. The flexible electronic structure of Cr facilitates easier charge transfer with Cr in several nearby atomic planes near the stacking fault, leading to significant changes in the d-electron number, orbital occupation number, and magnetic moments of Cr. [ABSTRACT FROM AUTHOR]

Angiosarcoma is a rare refractory soft-tissue tumor with a poor prognosis and is treated by radiotherapy. The fibroblast growth factor 1 (FGF1) mutant, with enhanced thermostability due to several substituted amino acids, inhibits angiosarcoma cell metastasis, yet the mechanism of action is unclear. This study aims to clarify the FGF1 mutant mechanism of action using ISOS-1 mouse angiosarcoma cells. The wild-type FGF1 or FGF1 mutant was added to ISOS-1 cells and cultured, evaluating cell numbers over time. The invasive and migratory capacity of ISOS-1 cells was assessed by transwell analysis. ISOS-1 cell radiosensitivity was assessed by colony formation assay after X-ray irradiation. To examine whether mitogen-activated protein kinase (MEK) inhibitor counteracts the FGF1 mutant effects, a combination of MEK inhibitor and FGF1 mutant was added to ISOS-1 cells and cultured. The FGF1 mutant was observed to inhibit ISOS-1 cell proliferation, invasion and migration by sustained FGF1 signaling activation. A MEK inhibitor suppressed the FGF1 mutant-induced inhibition of proliferation, invasion and migration of ISOS-1 cells. Furthermore, the FGF1 mutant enhanced radiosensitivity of ISOS-1 cells, but MEK inhibition suppressed the increased radiosensitivity. In addition, we found that the FGF1 mutant strongly inhibits actin polymerization, suggesting that actin cytoskeletal dynamics are closely related to ISOS-1 cell radiosensitivity. Overall, this study demonstrated that in ISOS-1 cells, the FGF1 mutant inhibits proliferation, invasion and migration while enhancing radiosensitivity through sustained activation of the MEK-mediated signaling pathway. [ABSTRACT FROM AUTHOR]

β-Ga2O3 with an ultra-wide bandgap demonstrates great promise in applications of space missions as power electronics and solar-blind photodetector. Unraveling the radiation damage effects on its material properties is of crucial importance, especially for improving the radiation tolerance of Ga2O3-based devices. Herein, we evaluate the formation energy of gallium and oxygen vacancy defects and comprehensively investigate their influence on the electronic and optical properties of β-Ga2O3 using first-principles calculations. Ga vacancies act as deep acceptors and produce p-type defects in β-Ga2O3, while the defective Ga2O3 with O vacancies exhibits the n-type characteristics. A semimetal characteristic is observed in the defective Ga2O3 with Ga vacancies, and an apparent optical absorption peak in the infrared spectral range emerges. Moreover, the self-compensation effect emerges when β-Ga2O3 contains both Ga vacancies and O vacancies, leading to the reduced absorption peak. The doping effect on the defect formation energy of β-Ga2O3 is also investigated, and Ga vacancies are found to be easily formed in the case of In doped β-Ga2O3 (InGa2O3) compared to the undoped β-Ga2O3, while O vacancies are much harder to form. This work provides insights into how gallium and oxygen vacancy defects alter electronic and optical properties of β-Ga2O3, seeking to strengthen its radiation tolerance. [ABSTRACT FROM AUTHOR]

Studies of the radiation tolerance and electrical behavior of gallium nitride (GaN) based devices are important for the next generation of high-power and high-voltage electronics that may be subjected to harsh environments such as nuclear reactor and fusion facilities, particle accelerators, and post-denotation environments. In this work, we study the behavior of Ga-polar and N-polar GaN Schottky diodes before and after exposure to fast and thermal + fast neutrons. Temperature-dependent current–voltage (I–V) and circular transmission line method (CTLM) measurements were used to study the electrical characteristics. A strong reduction in reverse leakage current and an increase in differential resistance in forward bias were observed after neutron irradiation. Thermionic emission (TE), Frenkel–Poole (FP) emission, and Fowler–Nordheim (FN) tunneling models were used to explain the forward and reverse I–V characteristics pre- and post-irradiation. The study confirms that Ga-polar and N-polar GaN Schottky diodes exhibit different electrical responses to fast and thermal neutron irradiations. The reverse bias characteristics of N-polar diodes are less affected after the fast neutron irradiation compared to Ga-polar diodes, while in the forward bias region, the electrical behavior after fast and thermal neutron irradiations is similar in Ga-polar and N-polar diodes. The results indicate that the role of orientation should be considered in the design of GaN-based radiation-tolerant electronics. [ABSTRACT FROM AUTHOR]