PSMA-directed nanoprobe enabling precision imaging and MR-guided chemoradiotherapy in prostate cancer.

A major challenge in soft X-ray spectroscopy is the efficient collection of the emitted X-rays by grazing-incidence mirrors. In this energy range, grazing-incidence mirrors are widely used as optics for the collection of light. The small angle of incidence necessarily limits the collection solid angle of soft X-ray spectrometers. We present a new mirror surface, a sagittal collimating diaboloid, that can both collect and focus light from a point source in an aberration-free manner. The usefulness of this optic in increasing throughput is demonstrated with a realistic example design of a moderate-sized (3 m) medium-resolution resonant inelastic X-ray scattering spectrometer.

An X-ray ionization beam position monitor (XIBPM) has been developed and evaluated for beam position diagnostics at a soft X-ray free-electron laser (FEL). The redesign was guided by electrostatic simulations and focused on mitigating electric-field distortions near the microchannel plate (MCP) and improving the internal electrode geometry and structural stability. The introduction of a conductive shielding cover effectively suppressed electric-field distortion from the MCP lead, substantially reducing displacement errors and improving measurement stability. A mesh-free electrode structure was also investigated, reducing photo-ion loss and increasing photo-ion transmission; however, under high-intensity FEL operation, the enhanced signal amplitude occasionally led to saturation effects. Beam position measurements were performed at photon energies of 500-1100 eV in both pink-beam and mono-beam modes. Under optimized conditions, a beam position resolution of approximately 24-25 µm was achieved for pulse-by-pulse analysis and improved to approximately 10-12 µm when averaging over ten pulses. The transverse ion profiles were found to be significantly broader than the actual photon beam size, reflecting intrinsic ion-transport dynamics and detector point-spread effects that dominate over the intrinsic photon beam size. These results demonstrate that the shielding cover represents the most significant improvement for accurate and stable beam position monitoring, while the electrode configuration can be selected flexibly depending on the operating regime. The improved XIBPM provides a practical, non-invasive solution for beam position diagnostics in soft X-ray FEL beamlines.

Natural killer cell-inspired dendritic mesoporous rare-earth nanoparticles potentiate X-ray-triggered reactive oxygen generation for low-dose radiotherapy-radiodynamic therapy.

Lipid-based carriers represent the leading technology for nanoparticle (NP) drug delivery. To this end, the incorporation of gold NPs into lipid coronas (LC) has long been of scientific and practical interest. However, challenges persist in confining the inorganic payload within the LC, while achieving high loading efficiency and control over the surface functionalization of Au NPs. Here, phospholipids are self-assembled on Au NPs suprastructures, generating lipid-coated nanoconstructs at an Au loading>90% in mass and maintaining the desired functionalization of the gold surface with 4-mercaptophenylboronic acid (MPBA). The resulting LC-MPBA-Au NPs exhibit the colloidal behaviour of the lipid vesicles together with the plasmonic properties of the Au suprastructures. According to molecular dynamics calculations, the phospholipids readily assemble on Au nanoparticle aggregates, with MPBA favouring the process. In addition, calculations suggest that surface corrugation of Au suprastructures promotes lipid coating. This indicates that preformed Au suprastructures characterized by surface irregularities are essential for attaining optimal loading efficiency within the LC. These nanohybrids hold significant promise for multimodal theranostics, as they combine high biocompatibility and efficient cellular uptake, can be tracked by computed tomography imaging, and possesses the physical characteristics of a bimodal radiosensitizer suitable for two complementary radiotherapy modalities based on X-ray irradiation and boron neutron capture.

Structural and mechanical alterations in polyoxymethylene: Insights from advanced irradiation technologies.

Simultaneous measurement methods for soft X-ray absorption spectroscopy (XAS) of solid-liquid interfaces and bulk liquids have been developed. The O K-edge XAS spectra of H2O/Au interfaces and bulk H2O were measured using a transmission-type liquid cell, in which the liquid layer was sandwiched between Au/Cr/Si3N4 and Si3N4 membranes. The XAS spectrum of bulk H2O was obtained using the transmission method by controlling the thickness of the liquid layer, whereas the XAS spectrum of the H2O/Au interface was obtained using the electron-yield method by measuring the drain currents from the Au surface after soft X-ray absorption. The XAS spectra of bulk H2O and the H2O/Au interfaces were differentiated to determine the appropriate measurement conditions for the solid-liquid interfaces interfaces.

We propose a wavelength-dispersive instrument for high-resolution soft X-ray spectroscopy at large-scale facilities like synchrotron radiation sources or free-electron lasers. Demonstrated by simulations at the Fe L-edge in the range from 700 eV to 730 eV, an energy resolution of (12-15) meV is enabled by a wavefront-corrected reflection zone plate (RZP) with an aperture of 40 mm × 190 mm on a spherical Si substrate (radius 69 m). Its tangential slope error and deformation are measured on-axis along the RZP to ±0.1 arcsec (r.m.s.) and ±6.1 nm (r.m.s.), respectively, and simulated at off-axis positions of the substrate with a similar amplitude. The surface waviness is compensated around the design energy of 715 eV by a two-dimensional, adapted grating groove distribution. As a benefit, the diffracted beam is collimated to a one-dimensional focal line whose length of 40 mm nearly equals the sagittal detector size (50 mm): no photons in the +1st diffraction order with an efficiency of 6.4% are lost, and the acceptance solid angle of 16 mrad × 3.3 mrad provides a high transmission of the signal from the source.

Preliminary results of soft X-ray measurements on Thailand Tokamak-1 using silicon-based spectrometer

Bilateral low-energy X-ray irradiation of vacuum-packed sausage: Microbial inactivation and quality preservation

FBX dosimeter - a theoretical approach for interpretation and optimisation.

Optical, dosimeric, and imaging properties of Tb4O7-doped 24BaO-4RE2O3-72B2O3 (RE=La, Gd, and Lu) glasses prepared by the melt-quenching technique.

Diosgenin alleviates radiation nephropathy by suppressing renal mTORC1 signalling with concomitant effects on the gut and liver.

Absorption-dominated optical response of soft x-ray to UV electromagnetic waves in a nanometer Au/Ag periodic multilayer

Objective.Modern self-contained x-ray irradiators offer a safer alternative to radionuclide sources for preclinical radiation research and can deliver conformal, clinically relevant dose distributions. However, concerns persist regarding their performance and biological toxicity as direct replacements in radiobiological studies. We assessed two preclinical x-ray platforms, a collimated cabinet X-Rad320 and an image-guided small animal radiation research platform (SARRP), for induced tumor response, tolerability, and dosimetric accuracy in a subcutaneous xenograft prostate tumor model under 2 Gy daily fractionated radiotherapy.Approach.Male athymic mice bearing 22Rv1 xenografts were randomized into cohorts receiving total doses of 10, 16, or 20 Gy (5, 8, or 10 2-Gy fractions) on either platform. Unirradiated controls were included. Tumor burden was quantified by the area under the tumor growth curve (AUC). Machine dose delivery accuracy was verified quarterly with alanine pellet dosimetry.Main results.Across regimens, no animals met humane body condition or weight endpoints or exhibited overt clinical toxicity. All irradiated groups had lower tumor normalized AUCs than controls, but the dose response was not clearly monotonic, and not all differences remained statistically significant after correcting for multiple comparisons. At 14 d post-treatment, SARRP at 16 Gy provided the greatest tumor suppression, with no significant additional benefit observed with 20 Gy. Histologicalγ-H2AX staining provided complementary evidence of a radiation-induced dose response.Significance.Focused x-ray platforms can reproducibly deliver conventional fractionated radiotherapy regimens in mice, inducing tumor response without overt clinical toxicity. However, platform-specific dose deviations highlight the need for rigorous dosimetric calibration and quality assurance to ensure they can effectively replace cesium-137 forin vivoresearch with comparable tumor control outcomes.

We report the use of reticular design to construct metal-organic frameworks (MOFs) with molecularly defined catalytic pores for bioorthogonal RNA manipulation in living cells. A library of crystalline MOFs with systematically varied Cu cluster geometries, pore dimensions, and chemical environments was assembled to interrogate how structural precision influences RNA recognition and conversion within confined spaces. By integration of redox-stable Cu(I) clusters with dimensionally matched mesopores, selected MOFs were capable of catalyzing efficient and quantitative RNA bond cleavage and formation reactions in living systems without external reducing agents. Small-angle X-ray scattering reveals that pore chemistry governs substrate positioning relative to catalytic centers, enabling preferential engagement of protected RNA and facilitated release of original RNA as products, thereby driving complete conversion. Synchrotron soft X-ray microscopy was used to visualize intracellular localization and integrity of MOF in cells, further validating MOF as a bioorthogonal catalyst. An amine-functionalized framework, MOF-248-NH2, enabled controlled sgRNA activation for CRISPR/Cas9 gene editing regulation in cells and treatment of cardiac disease in a canine model. These results establish reticular pore engineering as a powerful strategy to make MOFs programmable bioorthogonal catalysts.

Cervical cancer (CC) ranks as the third most common malignancy among women worldwide. Radiotherapy (RT) resistance represents a major cause of clinical treatment failure and disease progression. High-mobility group box-1 (HMGB1), a nuclear protein released during RT, has been implicated in the regulation of radiation resistance. This study aimed to establish HeLa RT-resistant (HeLa-R) cells and investigate the effect of HMGB1 on RT resistance and its underlying molecular pathway. HeLa-R cells were established through fractionated X-ray irradiation. Cell viability, proliferation, migration, and invasion were assessed using methyl thiazolyl tetrazolium (MTT), colony formation, Transwell migration, and invasion assays, respectively. HMGB1 expression was analyzed by quantitative RT-PCR, Western blot, and immunofluorescence. A phospho-kinase array was performed to evaluate phosphorylation levels of key kinase sites. Following fractionated X-ray irradiation, we successfully established HeLa-R cells, which exhibited significantly elevated HMGB1 expression compared to parental cells. HMGB1 knockdown suppressed RT resistance in HeLa-R cells, accompanied by increased phosphorylation of AMP-activated protein kinase (p-AMPK). Conversely, AMPK inhibition restored cell viability, colony formation, migration, and invasion in HMGB1-deficient HeLa-R cells. Mechanistically, in HeLa-R cells, mTOR was identified as a downstream effector of AMPK signaling. Separately, clinical analysis revealed that HMGB1 levels were significantly elevated, while p-AMPK levels were markedly reduced in tumor tissues from radioresistant patients compared with radiosensitive patients. In conclusion, our in vitro findings demonstrate that HMGB1 inhibition suppresses RT resistance in HeLa-R cells through activation of the AMPK/mTOR pathway. The clinical correlations between HMGB1, p-AMPK, and radiotherapy response support the potential relevance of this pathway, although further validation in patient tissues is required.

Perovskite-based Type-II heterojunctions offer a promising route for self-powered X-ray detection by leveraging built-in electric fields for carrier separation. However, solution deposition of a thick Type-II heterojunction, especially the heterojunction with a sharp interface, remains a challenge. Here, we demonstrate a thick-film CsPbBr3/Cs2AgBiBr6 Type-II heterojunction fabricated via electrostatic spray (E-spray) deposition with a solvent-compatible layer sequence. By depositing CsPbBr3 from a DMSO-based precursor first, followed by Cs2AgBiBr6 from a DMF-based precursor, we achieve a sharp interface with minimized intermixing, as evidenced by cross-sectional SEM and ToF-SIMS. UPS-derived band alignment, time-resolved photophysical characterization, and polarity-dependent electrical/X-ray response collectively support heterojunction-assisted carrier separation and collection. The device exhibits self-powered X-ray detection with a sensitivity of 226.82 μC Gyair-1 cm-2 at 0 V, a low detection limit of 0.028 μGyair s-1, and stable operation under repeated X-ray irradiation. This work provides a scalable strategy for high-sensitivity, low-power direct X-ray detectors, advancing perovskite-based imaging applications.

Medical image target segmentation is critical for clinical diagnosis and treatment, yet mainstream methods perform poorly on small medical targets due to inefficient sparse feature extraction and severe background interference. To tackle this issue, we propose Radiation Attenuation Characteristics Network (RAC-Net) inspired by the X-ray attenuation physical prior in CT imaging, aiming to boost small target segmentation accuracy for early lesion detection and localization. Specifically, RAC-Net integrates two tailored innovative modules: the Radiation Attenuation Salient Feature Extraction (RASFE) module leverages X-ray attenuation principles to extract small target Gaussian saliency features and suppress background noise, enhancing sparse feature representation; the Partial Volume Artifact Edge Enhancement (PVA) module embedded with CT Hounsfield Unit value prior fuses learnable neighborhood weights and physical prior weights, alleviating feature distortion and edge blurring caused by partial volume artifacts, while improving model robustness via clinical medical priors. Extensive experiments validate that RAC-Net achieves state-of-the-art performance in medical small target segmentation, with 18% DICE and 19% IOU improvements over advanced existing methods, providing solid support for early disease diagnosis and intervention.

This study aims to quantify the effect of aging-based tungsten deposition on half-value layer (HVL) and dose rate for a commercial superficial x-ray radiotherapy unit. Monte Carlo simulations were conducted using the MCNPX code to model the Xstrahl-100 x-ray unit. Five beams with peak voltages of 30, 50, 80, 95 and 100 kVp were modelled. A thin tungsten layer was introduced on the inner wall of exit window of the X-ray tube. Photon fluence were tallied at the applicator's exit and HVL values were calculated for all beams.. The thickness of the tungsten layer varied from 0.0001mm up to 0.01mm to simulate progressive aging-related deposition. The tungsten thicknesses required to produce 2, 5, and 10% variation in HVL and photon dose rate were determined. The HVL increased linearly with tungsten thickness, whereas the dose rate decreased exponentially with increasing tungsten thickness. The sensitivity of HVL and dose rate to tungsten deposition decreased with increasing beam energy, with the 30 kVp beam showing the greatest sensitivity. On average, across all beam energies, achieving a 5% variation in HVL required 1.73 times greater tungsten thickness than for a 5% variation in dose rate. Tungsten deposition significantly alters the HVL and photon absorbed dose rate in a superficial X-ray radiotherapy unit, with low-energy beams showing the greatest sensitivity.