Search Results (180)

The impact of 230-MeV Xe¹³² ion irradiation on the structural, optical, and luminescent properties of YAG:Ce single crystals is investigated over a fluence range of 10¹¹–10¹⁴ ions/cm². Optical absorption; cathodo-, X-ray, and photoluminescence; and X-ray diffraction are employed to analyze radiation-induced changes. Irradiation leads to the formation of Frenkel (F, F⁺) and antisite defects and attenuates Ce³⁺ emission (via enhanced nonradiative processes and Ce³⁺ → Ce⁴⁺ recharging). A redistribution between the fast and slow components of the Ce³⁺-emission is considered. Excitation spectra show the suppression of exciton-related emission bands, as well as a shift of the excitation onset due to increased lattice disorder. XRD data confirm partial amorphization and a high level of local lattice disordering, both increasing with irradiation fluence. These findings provide insight into radiation-induced processes in YAG:Ce, which are relevant for its application in radiation–hard scintillation detectors. Full article

The phototherapeutic applications of porphyrin-based nanoscale metal–organic frameworks (nMOFs) are limited by the poor penetration of conventional excitation light sources into biological tissues. Radiodynamic therapy (RDT), which directly excites photosensitizers using X-rays, can overcome the issue of tissue penetration. However, RDT faces the problems of low energy conversion efficiency, requiring a relatively high radiation dose, and the potential to cause damage to normal tissues. Researchers have found that by using some metals with high atomic numbers (high Z) as X-ray scintillators and coordinating them with porphyrin photosensitizers to form MOF materials, the excellent antitumor effect of radiotherapy (RT) and RDT can be achieved under low-dose X-ray irradiation, which can not only effectively avoid the penetration limitations of light excitation methods but also eliminate the defect issues associated with directly using X-rays to excite photosensitizers. This review summarizes the relevant research work in recent years, in which researchers have used metal ions with high Z, such as Hf⁴⁺, Th⁴⁺, Ta⁵⁺, and Bi³⁺, in coordination with carboxyl porphyrins to form MOF materials for combined RT and RDT toward various cancer cells. This review compares the therapeutic effects and advantages of using different high-Z metals and introduces the application of the heavy atom effect. Furthermore, it explores the introduction of a chemodynamic therapy (CDT) mechanism through iron coordination at the porphyrin center, along with optimization strategies such as oxygen delivery using hemoglobin to enhance the efficacy of these MOFs as radiosensitizers. This review also summarizes the potential of these materials in preclinical applications and highlights the current challenges they face. It is expected that the summary and prospects outlined in this review can further promote preclinical biomedical research into and the development of porphyrin-based nMOFs. Full article

Exposure to high-linear energy transfer (LET) heavy ions, such as ²⁸Si, poses a significant cancer risk for astronauts. While previous studies have linked high-LET radiation exposure to persistent oxidative stress and dysregulated stress responses in intestinal crypt cells with an increased risk of tumorigenesis, the relationship between IR-induced oxidative DNA damage and intestinal cancer risk remains incompletely understood. Here, we investigated the time-dependent effects of ²⁸Si-ion radiation on intestinal tumorigenesis and oxidative DNA damage in Apc^1638N/+ mice, a model for human intestinal cancer predisposition. Male Apc^1638N/+ mice were exposed to 10 cGy of either γ-rays (low-LET) or ²⁸Si-ions (high-LET), and intestinal tumor burden was assessed at 60 and 150 days post-irradiation. While both radiation groups showed modest, non-significant tumor increases at 60 days, ²⁸Si-irradiated mice exhibited an approximately 2.5-fold increase in tumor incidence by 150 days, with a higher incidence of invasive carcinomas compared to γ and sham groups. Serum 8-OxodG levels, a marker of systemic oxidative stress, were significantly elevated in the ²⁸Si-ion group, correlating with increased intestinal 8-OxodG staining. Additionally, assessment of the proliferation marker Cyclin D1 and metaplasia marker Guanylyl Cyclase C (GUCY2C) also revealed significant crypt cell hyperproliferation accompanied by increased metaplasia in ²⁸Si-exposed mouse intestines. Positive correlations between serum 8-OxodG and tumor-associated endpoints provide compelling evidence that exposure to ²⁸Si-ions induces progressive intestinal tumorigenesis through sustained oxidative DNA damage, crypt cell hyperproliferation, and metaplastic transformation. This study provides evidence in support of the radiation quality-dependent progressive increase in systemic and intestinal levels of 8-OxodG during intestinal carcinogenesis. Moreover, the progressive increase in oxidative DNA damage and simultaneous increase in oncogenic events after ²⁸Si exposure also suggest that non-targeted effects might be a significant player in space radiation-induced intestinal cancer development. The correlation between serum 8-OxodG and oncogenic endpoints supports its potential utility as a predictive biomarker of high-LET IR-induced intestinal carcinogenesis, with implications for astronaut health risk monitoring during long-duration space missions. Full article

Thin amorphous oxide films (a-SiO₂, a-Al₂O₃, a-MgO) were prepared by magnetron sputtering deposition. Their response to high-energy heavy ion beams (23 MeV I, 18 MeV Cu, 2.5 MeV Cu) and gamma-ray (1.25 MeV) irradiation was studied by elastic recoil detection analysis and infrared spectroscopy. It was established that their high radiation hardness is due to a high level of disorder, already present in as-prepared samples, so the high-energy heavy ion irradiation cannot change their structure much. In the case of a-SiO₂, this resulted in a completely different response to high-energy heavy ion irradiation found previously in thermally grown a-SiO₂. In the case of a-MgO, only gamma-ray irradiation was found to induce significant changes. Full article

Increasing evidence highlights the role of aberrant circadian rhythm gene expression in glioblastoma (GBM) progression, but the impact of the circadian rhythm gene network on GBM molecular profiles and prognosis remains unclear. A total of 1042 GBM samples from six public datasets, TCGA and CGGA, were analyzed, with GBM samples stratified into three circadian core-gene patterns using unsupervised clustering based on the expression profiles of 17 circadian rhythm genes. The Limma R package identified differentially expressed genes (DEGs) among the three patterns, and a secondary clustering system, termed circadian-related gene pattern, was established based on DEGs. A circadian risk score was constructed using the Least Absolute Shrinkage and Selection Operator (LASSO) regression algorithm, and the efficiency of these patterns and the circadian risk score in distinguishing molecular profiles and predicting prognosis was systematically analyzed. The relationship between the circadian risk score and response to immune or targeted therapy was examined using the GSE78200 and IMvigor210 datasets. The results showed that GBM patients were clustered into three circadian core-gene patterns based on the expression profiles of 17 core circadian genes, with distinct molecular profiles, malignant characteristics, and patient prognoses among the patterns. Thirty-two DEGs among these patterns were identified and termed circadian-related genes, and secondary clustering based on these 32 DEGs classified GBM samples into two circadian-related gene patterns, which also predicted molecular profiles and prognosis. A circadian risk scoring system was established, allowing the calculation of individual risk scores based on the expression of 10 genes, where GBM patients with lower circadian risk scores had prolonged overall survival and less aggressive molecular subtypes, while higher circadian risk scores correlated with better responses to MAPK-targeted therapy. In conclusion, this study established two clustering patterns based on 17 circadian rhythm genes or 32 circadian-related genes, enabling the rapid classification of GBM patients with distinct molecular profiles and prognoses, while the circadian risk scoring system effectively predicted survival, molecular profiles, and therapeutic responses for individual GBM patients, demonstrating that the circadian rhythm gene network can distinguish molecular profiles and prognosis in GBM. Full article

The recovery of radiation damage induced by 231-MeV xenon ions with varying fluence (from 5 × 10¹¹ to 2 × 10¹⁴ cm⁻²) in α-Al₂O₃ (corundum) single crystals has been studied by means of isochronal thermal annealing of radiation-induced optical absorption (RIOA). The integral of elementary Gaussians (product of RIOA spectrum decomposition) OK has been considered as a concentration measure of relevant oxygen-related Frenkel defects (neutral and charged interstitial-vacancy pairs, F-H, F⁺-H⁻). The annealing kinetics of these four ion-induced point lattice defects has been modelled in terms of diffusion-controlled bimolecular recombination reactions and compared with those carried out earlier for the case of corundum irradiation by fast neutrons. The changes in the parameters of interstitial (mobile component in the recombination process) annealing kinetics—activation energy E and pre-exponential factor X—in ion-irradiated crystals are considered. Full article

Radiotherapy (RT) has undergone transformative advancements since its inception over a century ago. This review highlights the most promising and impactful innovations shaping the current and future landscape of RT. Key technological advances include adaptive radiotherapy (ART), which tailors treatment to daily anatomical changes using integrated imaging and artificial intelligence (AI), and advanced image guidance systems, such as MR-LINACs, PET-LINACs, and surface-guided radiotherapy (SGRT), which enhance targeting precision and minimize collateral damage. AI and data science further support RT through automation, improved segmentation, dose prediction, and treatment planning. Emerging biological and targeted therapies, including boron neutron capture therapy (BNCT), radioimmunotherapy, and theranostics, represent the convergence of molecular targeting and radiotherapy, offering personalized treatment strategies. Particle therapies, notably proton and heavy ion RT, exploit the Bragg peak for precise tumor targeting while reducing normal tissue exposure. FLASH RT, delivering ultra-high dose rates, demonstrates promise in sparing normal tissue while maintaining tumor control, though clinical validation is ongoing. Spatially fractionated RT (SFRT), stereotactic techniques and brachytherapy are evolving to treat challenging tumor types with enhanced conformality and efficacy. Innovations such as 3D printing, Auger therapy, and hyperthermia are also contributing to individualized and site-specific solutions. Across these modalities, the integration of imaging, AI, and novel physics and biology-driven approaches is redefining the possibilities of cancer treatment. This review underscores the multidisciplinary and translational nature of modern RT, where physics, engineering, biology, and informatics intersect to improve patient outcomes. While many approaches are in various stages of clinical adoption and investigation, their collective impact promises to redefine the therapeutic boundaries of radiation oncology in the coming decade. Full article

The U-shaped Metal-Oxide-Semiconductor Field-Effect Transistor (UMOS or trench FET) is one of the most widely used semiconductor power devices worldwide, increasingly replacing the traditional vertical double-diffused MOSFET (DMOSFET) in various applications due to its superior electrical performance. However, a detailed experimental comparison of ion-induced Single-Event Burnout (SEB) in similarly rated silicon (Si) UMOS and DMOS devices remains lacking. This study presents a comprehensive experimental comparison of ion-induced charge collection mechanisms and SEB susceptibility in similarly rated Si UMOS and DMOS devices. Charge collection mechanisms due to alpha particles from ²⁴¹Am radiation source are analyzed, and SEB cross sections induced by heavy ions from particle accelerators are directly compared. The implications of the unique gate structure of Si UMOSFETs on their reliability in harsh radiation environments are discussed based on technology computer-aided design (TCAD) simulations. Full article

In this work, the effects of heavy ion strike position, incident angle, linear energy transfer (LET) value, ambient temperature, bias conditions, and the synergistic effects of total dose irradiation on the single-event transient (SET) in silicon-germanium heterojunction bipolar transistors on silicon-on-insulator (SiGe-on-SOI HBTs) were investigated using TCAD simulations. It was demonstrated that, compared to the bulk SiGe HBT, the SiGe-on-SOI HBT exhibits lower transient current and less charge collection, indicating better resistance to SET. The SET response is more pronounced when heavy ions strike vertically from the emitter and base regions. Transient current and collected charge escalate with increasing incident angle, demonstrating a strong linear correlation with LET values. As the temperature decreases, the peak transient current increases, while the pulse duration decreases and the total collected charge diminishes. After total dose irradiation, the peak transient current in the SiGe-on-SOI HBT decreases, whereas the damage was more severe in the absence of irradiation. Under collector positive bias and positive bias, significant SET responses were observed, while cutoff bias and substrate bias exhibited better resistance to SET damage. These findings provide critical insights into radiation-hardened design strategies for the SiGe-on-SOI HBT. Full article

Delta-like 3 (DLL3) is an oncogenic protein aberrantly expressed in several tumors, particularly in small-cell lung cancer. DLL3-targeted therapies have recently made significant progress, demonstrating promising preclinical and clinical efficacy. This review aims to explore the mechanisms, challenges, and future opportunities associated with therapies targeting DLL3 for cancer treatment. The biological characteristics of DLL3 and its role in the Notch signaling pathway are introduced first, delving into the role of DLL3 in tumorigenesis and cancer progression. Next, current therapeutic approaches targeting DLL3 are described, including antibody–drug conjugates, T cell engagers, chimeric antigen receptor T cells, and radiopharmaceutical therapy, highlighting their effectiveness and safety in clinical trials. Despite the promising prospects, difficulties remain in the use of DLL3 as a therapeutic target due to tumor heterogeneity, the development of resistance, potential adverse effects, and barriers to patient stratification. Therefore, the potential of combination therapies, the use of innovative drug delivery systems, and ongoing clinical trial advancements are also discussed. Finally, the potential of DLL3-targeted therapies is summarized, highlighting the importance of multidisciplinary research to guide the clinical application and optimization of this emerging treatment strategy. These approaches might provide new therapeutic options, potentially starting a new era in cancer treatment. Full article

The primary objective of this research is to comprehensively investigate the equivalence of single-event effects (SEEs) in silicon carbide metal-oxide semiconductor field-effect transistors (SiC MOSFETs) that are induced by protons and heavy ions. The samples utilized in the experiments are the fourth-generation symmetric groove gate SiC MOSFETs. Proton irradiation experiments were meticulously executed at varying energies, namely 70 MeV, 100 MeV, and 200 MeV, while heavy-ion irradiation was carried out using 138 MeV Cl ions. During these experiments, the drain–source current (I_DS) and drain–source voltage (V_DS) were continuously and precisely monitored in real time. Experimental results demonstrate that single-event burnout (SEB) susceptibility correlates strongly with proton energy and applied drain–source bias. Notably, SiC MOSFETs exhibit a stronger tolerance to proton SEB compared to heavy-ion SEB. Proton irradiation results in a sudden elevation in I_DS, whereas heavy-ion irradiation leads to a gradual increase. In summary, the mechanism underlying proton-induced SEE is intricately related to the ionization of secondary particles. Future research endeavors should place a greater emphasis on comprehensively considering proton effects to establish a more complete and effective evaluation system for SiC MOSFET SEEs. Full article

High-purity germanium (HPGe) detectors occupy a prominent position in fields such as radiation detection and aerospace because of their excellent energy resolution and wide detection range. To achieve a broader detection range, conventional HPGe detectors often need to be expanded to cubic-centimeter-scale volumes. However, this increase in volume leads to a large detector area, which in turn increases the detector capacitance, affecting the detector’s noise level and performance. To address this issue, this study proposes a novel high-purity germanium drift detector (HPGeDD). The design features a small-area central collecting cathode surrounded by concentric anode rings, with a resistive chain interposed between the anode rings to achieve self-dividing voltage. This design ensures that the detector’s capacitance is only related to the area of the central collecting cathode, independent of the overall active area, thus achieving a balance between a small capacitance and large active area. Electrical performance simulations of the novel detector were conducted using the semiconductor simulation software Sentaurus TCAD (P-2019.03). The results show a smooth electric potential distribution within the detector, forming a lateral electric field, as well as a lateral hole drift channel precisely directed toward the collecting cathode. Furthermore, simulations of heavy ion incidence were performed to investigate the detector’s carrier collection characteristics. The simulation results demonstrate that the HPGeDD exhibits advantages such as fast signal response and short collection time. The design proposal presented in this study offers a new solution to the problem of excessive capacitance in conventional HPGe detectors, expands their application scope, and provides theoretical guidance for subsequent improvements, optimizations, and practical manufacturing. Full article

Increased stemness of cancer cells exacerbates radioresistance, thereby greatly limiting the efficacy of radiotherapy. In order to study the changes in cancer cell stemness during radiotherapy, we established a radioresistance model of human non-small cell lung cancer A549 cells and obtained A549 radioresistant cells (A549-RR). We sampled the cells at different time points during the modeling process and investigated the heterogeneity of each group of cells using single-cell sequencing. Cells in the early stages of fractionated irradiation were found to be significantly up-regulated in stemness, and a subpopulation of cells producing this response was screened and referred to as “radiation-induced stemness-responsive cancer cells”. They were undergoing stemness response, energy metabolism reprogramming, and progressively differentiating into cells with more diverse and malignant phenotypes in order to attenuate the killing effect of radiation. Furthermore, we demonstrated that such responses might be driven by the activation of the EGFR-Hippo signaling pathway axis, which also plays a crucial role in the development of radioresistance. Our study reveals the dynamic evolution of cell subpopulation in cancer cells during fractionated radiotherapy; the early stage of irradiation can determine the destiny of the radiation-induced stemness-responsive cancer cells. The activation of stemness-like phenotypes during the development of radioresistance is not the result of dose accumulation but occurs during the early stage of radiotherapy with relatively low-dose irradiation. The degree of the radiation-induced stemness response of cancer cells mediated by the EGFR-Hippo signaling pathway might be a potential predictor of the efficacy of radiotherapy and the development of radioresistance. Full article

More than 70% of cancer patients receive radiotherapy during their treatment, with consequent various side effects on normal cells due to high ionizing radiation doses despite tumor shrinkage. To date, many radioprotectors and radiosensitizers have been investigated in preclinical studies, but their use has been hampered by the high toxicity to normal cells or poor tumor radiosensitization effects. Genistein is a naturally occurring isoflavone found in soy products. It selectively sensitizes tumor cells to radiation while protecting normal cells from radiation-induced damage, thus improving the efficacy of radiotherapy and consequent therapeutic outcomes while reducing adverse effects. Genistein protects normal cells by its potent antioxidant effect that reduces oxidative stress and mitigates radiation-induced apoptosis and inflammation. Conversely, genistein increases the radiosensitivity of tumor cells through specific mechanisms such as the inhibition of DNA repair, the arrest of the cell cycle in the G₂/M phase, the generation of reactive oxygen species (ROS), and the modulation of apoptosis. These effects increase the cytotoxicity of radiation. Preclinical studies demonstrated genistein efficacy in various cancer models, such as breast, prostate, and lung cancer. Despite limited clinical studies, the existing evidence supports the potential of genistein in improving the therapeutic effect of radiotherapy. Future research should focus on dosage optimization and administration, the exploration of combination therapies, and long-term clinical trials to establish genistein benefits in clinical settings. Hence, the unique ability of genistein to improve the radiosensitivity of tumor cells while protecting normal cells could be a promising strategy to improve the efficacy and safety of radiotherapy. Full article

Traditional defect recovery methods rely on high-temperature annealing, often exceeding 750 °C for FeCrAl. In this study, we introduce electron wind force (EWF)-assisted annealing as an alternative approach to mitigate irradiation-induced defects at significantly lower temperatures. FeCrAl samples irradiated with 5 MeV Zr²⁺ ions at a dose of 10¹⁴ cm⁻² were annealed using EWF at 250 °C for 60 s. We demonstrate a remarkable transformation in the irradiated microstructure, where significant increases in kernel average misorientation (KAM) and low-angle grain boundaries (LAGBs) typically indicate heightened defect density; the use of EWF annealing reversed these effects. X-ray diffraction (XRD) confirmed these findings, showing substantial reductions in full width at half maximum (FWHM) values and a realignment of peak positions toward their original states, indicative of stress and defect recovery. To compare the effectiveness of EWF, we also conducted traditional thermal annealing at 250 °C for 7 h, which proved less effective in defect recovery as evidenced by less pronounced improvements in XRD FWHM values. Full article