X-ray Research Articles

WiTUnet: A U-shaped architecture integrating CNN and Transformer for improved feature alignment and local information fusion

Low-dose computed tomography (LDCT) has emerged as the preferred technology for diagnostic medical imaging due to the potential health risks associated with X-ray radiation and conventional computed tomography (CT) techniques. While LDCT utilizes a lower radiation dose compared to standard CT, it results in increased image noise, which can impair the accuracy of diagnoses. To mitigate this issue, advanced deep learning-based LDCT denoising algorithms have been developed. These primarily utilize Convolutional Neural Networks (CNNs) or Transformer Networks and often employ the Unet architecture, which enhances image detail by integrating feature maps from the encoder and decoder via skip connections. However, existing methods focus excessively on the optimization of the encoder and decoder structures while overlooking potential enhancements to the Unet architecture itself. This oversight can be problematic due to significant differences in feature map characteristics between the encoder and decoder, where simple fusion strategies may hinder effective image reconstruction. In this paper, we introduce WiTUnet, a novel LDCT image denoising method that utilizes nested, dense skip pathway in place of traditional skip connections to improve feature integration. Additionally, to address the high computational demands of conventional Transformers on large images, WiTUnet incorporates a windowed Transformer structure that processes images in smaller, non-overlapping segments, significantly reducing computational load. Moreover, our approach includes a Local Image Perception Enhancement (LiPe) module within both the encoder and decoder to replace the standard multi-layer perceptron (MLP) in Transformers, thereby improving the capture and representation of local image features. Through extensive experimental comparisons, WiTUnet has demonstrated superior performance over existing methods in critical metrics such as Peak Signal-to-Noise Ratio (PSNR), Structural Similarity (SSIM), and Root Mean Square Error (RMSE), significantly enhancing noise removal and image quality. The code is available on github https://github.com/woldier/WiTUNet.

Hepatic Stellate Cell-mediated Increase in CCL5 Chemokine Expression after X-ray Irradiation Determined In Vitro and In Vivo.

Radiation exposure causes hepatitis which induces hepatic steatosis and fibrosis. Although hepatic stellate cells (HSCs) have been considered potential pathological modulators for the development of hepatitis due to viral and microbial infections, their involvement in radiation-induced hepatitis is yet to be determined. This study aimed to clarify the relationship between radiation exposure and expressions of inflammatory cytokines and chemokines in HSCs in vitro and invivo. HSCs were obtained from 1-week-old mice, known to be highly sensitive to radiation-induced hepatocellular carcinoma, using a newly established method combining liver perfusion, cell dissociation, and density gradient centrifugation, followed by magnetic negative selection of hematopoietic and endothelial cells with anti-CD45.2 and CD146 antibodies. The isolated HSCs were confirmed by the expression of desmin and glial fibrillary acidic protein (GFAP). We demonstrated that primary cultured HSCs, exposed to X-ray irradiation (0, 1.9, and 3.8 Gy) and cultured for 3 and 7 days, produced elevated levels of C-C motif chemokine ligand 5 (CCL5, also known as RANTES) inflammatory chemokine in a dose-dependent manner. An invivo immunofluorescence method confirmed that increased CCL5 signals were observed in GFAP-positive HSCs in mouse livers 7 days after whole-body X-ray irradiation (1.9 and 3.8 Gy). Adequate expression of C-C motif chemokine receptor 5 (Ccr5), a receptor for CCL5, was also detected using real-time PCR in the liver of both irradiated and non-irradiated mice. Taken together, our data suggest that HSCs may drive hepatitis via CCL5/CCR5 axis in the liver under radiation-induced stress. Furthermore, this newly established experimental protocol can help evaluate the expression of other inflammatory cytokines in primary cultures of HSCs isolated from infant mice.

Structural characterization and dosimetric response evaluation of (SnO<sub>2</sub>)<sub>0.3</sub>(TiO<sub>2</sub>)<sub>0.7</sub> thin film

This study investigates the effect of X-ray radiation on the I-V characteristics of (SnO2)0.3(TiO2)0.7 thin film in a voltage range of 0- 8 The thin film was developed using the aerosol assisted chemical deposition technique. The amorphous character of the films was shown by the XRD spectra, which showed peaks corresponding to SnO2 and TiO2. Smooth surface morphology with tiny poses was indicated by the FESEM picture, and 2.73 μm film thickness was identified in the cross-sectional investigation. The I-V characteristics result indicates that the electrical conductivity changes throughout a range of applied voltages, from 0 to 8 V. The I-V characteristic measurements obtained during irradiation with X-ray dosage (dose rate) ranging from 100 cGy (250 cGy/min) to 200 cGy (350 cGy/min) and a voltage range of 1.0V to 8.0 V indicate that the current increases linearly with X-ray doses and dose rate. The thin film’s ability to undergo structural changes due to X-ray radiation makes it a valuable dosimetric sensor.

Determination of RBE of 450 MeV/nucleon carbon ions using the micronucleus test and survival of mice after irradiation in different regions of the Bragg curve

Purpose Determination of the value of relative biological effectiveness (RBE) of heavy charged ions in vivo is an important task for their optimal use in particle radiotherapy. The aim of this study was to determine the RBE value of a beam of carbon ions with an energy of 450 MeV/nucleon in different regions of the Bragg curve in irradiation of mice at low, medium, and high doses in comparison with X-ray radiation. Materials and methods SHK mice (n = 330) were irradiated in three regions of the Bragg curve in the dose range of 0–1.5 Gy for cytogenetic damage detection and at a dose of 6.5 Gy for determination of 30-day survival. For irradiation of mice in the Bragg peak, two widths of a spread-out Bragg peak (SOBP) were used: 10 mm (LET ∼100 keV/µm) and 30 mm (LET ∼39 keV/µm). Results The RBE value was 0.8–0.9 before the Bragg peak (LET ∼15 keV/µm) and 0.8 after the peak (LET ∼5 keV/µm), and did not depend on the determination method, despite the differences in LET values. The RBE value determined by the micronucleus test was 1.1–1.7 for the 10-mm-wide SOBP and 1.0–1.3 for the 30-mm-wide SOBP, with the highest RBE value obtained in the low-dose region upon irradiation of mice in the 10-mm-wide Bragg peak. The RBE values in the high-dose region determined by the 30-day survival test lay in the range from 1.4 to 2.6 depending on the width of the Bragg peak and the chosen criterion for calculating the value. The RBE values in the 10-mm-wide Bragg peak (LET ∼100 keV/µm) were higher than those in the 30-mm-wide Bragg peak (LET ∼39 keV/µm) at all used criteria. Conclusions The present findings suggest that there is the complex relationship between LET and organism response to accelerated charged particle radiation, and the contribution of specific factors and mechanisms must be further considered.

Multi-epoch UV–X-Ray Spectral Study of NGC 4151 with AstroSat

We present a multiwavelength spectral study of NGC 4151 based on five epochs of simultaneous AstroSat observations in the near-ultraviolet (NUV) to hard X-ray band (∼0.005–80 keV) during 2017–2018. We derived the intrinsic accretion disk continuum after correcting for internal and Galactic extinction, contributions from broad- and narrow-line regions, and emission from the host galaxy. We found a bluer continuum at brighter UV flux, possibly due to variations in the accretion disk continuum or the UV reddening. We estimated the intrinsic reddening, E(B − V) ∼ 0.4, using high-resolution Hubble Space Telescope (HST)/STIS spectrum acquired in 2000 March. We used thermal Comptonization, neutral and ionized absorption, and X-ray reflection to model the X-ray spectra. We obtained the X-ray absorbing neutral column varying between N H ∼1.2 and 3.4 × 1023 cm−2, which are ∼100 times larger than that estimated from UV extinction, assuming the Galactic dust-to-gas ratio. To reconcile this discrepancy, we propose two plausible configurations of the obscurer: (a) a two-zone obscurer consisting of dust-free and dusty regions, divided by the sublimation radius, or (b) a two-phase obscurer consisting of clumpy, dense clouds embedded in a low-density medium, resulting in a scenario where a few dense clouds obscure the compact X-ray source substantially, while the bulk of UV emission arising from the extended accretion disk passes through the low-density medium. Furthermore, we find a positive correlation between the X-ray absorption column and NUV − far-UV color and UV flux, indicative of enhanced winds possibly driven by the “bluer-when-brighter” UV continuum.

New Insights on the Burst Release Kinetics of Spray-Dried PLGA Microspheres.

Spray drying is one of the leading manufacturing methods for active pharmaceutical ingredients (APIs) owing to its rapid, single-step, and cost-effective nature. It also has the capacity to generate microspheres capable of controlled release of APIs including biomolecules and vaccines. However, one of the key challenges of spray-dried formulations especially with poly(lactic-co-glycolic acid) (PLGA)-based controlled-release injectables is burst release, where a significant fraction of the API is released prematurely within a short period of time following administration, leading to detrimental impact on the performance and quality of end products. This study uses a model API, bovine serum albumin (BSA) protein, to identify the sources of burst release that may affect the kinetics and performance of long-acting injectable microsphere formulations. Spray-dried microspheres with various formulations (i.e., variable BSA/PLGA ratios) were characterized in terms of their morphology, particle size, surface area, thermal properties, moisture content, as well as chemical compositions and their distributions to investigate the impact of spray drying on the burst release phenomenon. The results suggest that a relatively high initial release (85%) observed is mainly attributed to the protein distribution close to the particle surface. Morphology analysis provided evidence that the microspheres retained their spherical structure during the burst release phase. X-ray photoelectron spectroscopy, hard X-ray photoelectron spectroscopy, and argon cluster sputtering-assisted time-of-flight secondary ion mass spectrometry analysis suggest an enrichment of PLGA on particle surfaces with buried BSA protein. The statistically significant difference in particle size and surface area between three different formulations may be responsible for an initial variation in release but did not seem to alter the overall burst release profile. Considering the suggested source of burst release, the two-fluid spray-drying method, characterized by a single liquid feed delivering a preprepared emulsion, generated matrix-type microspheres with a surface layer of PLGA, as evidenced by surface analysis. The PLGA surface layer proved to be prone to degradation and pore formation, allowing for faster diffusion of BSA out of the microspheres, resulting in a burst release. Increasing the polymer concentration did not seem to halt this process.

A Rapid Sequence of Solar Energetic Particle Events Associated with a Series of Extreme-ultraviolet Jets: Solar Orbiter, STEREO-A, and Near-Earth Spacecraft Observations

A series of solar energetic electron (SEE) events was observed from 2022 November 9 to November 15 by Solar Orbiter, STEREO-A, and near-Earth spacecraft. At least 32 SEE intensity enhancements at energies >10 keV were clearly distinguishable in Solar Orbiter particle data, with 13 of them occurring on November 11. Several of these events were accompanied by ≲10 MeV proton and ≲2 MeV nucleon−1 heavy-ion intensity enhancements. By combining remote-sensing and in situ data from the three viewpoints (Solar Orbiter and STEREO-A were ∼20° and ∼15° east of Earth, respectively), we determine that the origin of this rapid succession of events was a series of brightenings and jetlike eruptions detected in extreme ultraviolet (EUV) observations from the vicinity of two active regions. We find a close association between these EUV phenomena, the occurrence of hard X-ray flares, type III radio bursts, and the release of SEEs. For the most intense events, usually associated with extended EUV jets, the distance between the site of these solar eruptions and the estimated magnetic connectivity regions of each spacecraft with the Sun did not prevent the arrival of electrons at the three locations. The capability of jets to drive coronal fronts does not necessarily imply the observation of an SEE event. Two peculiar SEE events on November 9 and 14, observed only at electron energies ≲50 keV but rich in ≲1 MeV nucleon−1 heavy ions, originated from slow-rising confined EUV emissions, for which the process resulting in energetic particle release to interplanetary space is unclear.

Green upgrading of SPring-8 to produce stable, ultrabrilliant hard X-ray beams.

SPring-8-II is a major upgrade project of SPring-8 that was inaugurated in October 1997 as a third-generation synchrotron radiation light source. This upgrade project aims to achieve three goals simultaneously: achievement of excellent light source performance, refurbishment of aged systems, and significant reduction in power consumption for the entire facility. A small emittance of 50 pm rad will be achieved by (1) replacing the existing double-bend lattice structure with a five-bend achromat one, (2) lowering the stored beam energy from 8 to 6 GeV, (3) increasing the horizontal damping partition number from 1to 1.3, and (4) enhancing horizontal radiation damping by installing damping wigglers in long straight sections. The use of short-period in-vacuum undulators allows ultrabrilliant X-rays to be provided while keeping a high-energy spectral range even at the reduced electron-beam energy of 6 GeV. To reduce power consumption, the dedicated, aged injector system has been shut down and the high-performance linear accelerator of SACLA, a compact X-ray free-electron laser (XFEL) facility, is used as the injector of the ring in a time-shared manner. This allows the simultaneous operation of XFEL experiments at SACLA and full/top-up injection of the electron beam into the ring. This paper overviews the concept of the SPring-8-II project, the system design of the light source and the details of the accelerator component design.

An X-Ray Significantly Variable, Luminous, Type 2 Quasar at z = 2.99 with a Massive Host Galaxy

We present a comprehensive X-ray analysis and spectral energy distribution (SED) fitting of WISEA J171419.96+602724.6, an extremely luminous type 2 quasar at z = 2.99. The source was suggested as a candidate Compton-thick (column density N H > 1.5×1024 cm−2) quasar by a short XMM-Newton observation in 2011. We recently observed the source with deep NuSTAR and XMM-Newton exposures in 2021 and found that the source has a lower obscuration of N H ∼ 5×1022 cm−2 with an about four times lower flux. The two epochs of observations suggested that the source was significantly variable in X-ray obscuration, flux, and intrinsic luminosity at 2σ–3σ in less than 2.5 yr (in the source rest frame). We performed SED fitting of this source using Code Investigating GALaxy Emission thanks to its great availability of multiwavelength data (from hard X-rays to radio). The source is very luminous, with a bolometric luminosity of L BOL ∼ 2.5 × 1047 erg s−1. Its host galaxy has a huge star formation rate (SFR) of ∼1280 M ☉ yr−1 and a huge stellar mass of ∼1.1 × 1012 M ☉. The correlation between the SFR and stellar mass of this source is consistent with what was measured in the high-z quasars. It is also consistent with what was measured in the main-sequence star-forming galaxies, suggesting that the presence of the active nucleus in our target does not enhance or suppress the SFR of its host galaxy. The source is an infrared hyperluminous, obscured galaxy with a significant amount of hot dust in its torus and shares many similar properties with hot, dust-obscured galaxies.

Near-infrared scintillation properties of Nd-doped CaYAl3O7 single crystals

We prepared Nd-doped CaYAl3O7 single crystals with different Nd concentrations of 0.1, 0.5, 1.0, 5.0, 10, and 20% by the floating zone method. Photoluminescence (PL) and scintillation properties of all the samples were investigated, and the performance as near-infrared (NIR) scintillators was evaluated. All the samples exhibited some luminescence peaks of 4f-4f transitions of Nd3+ in PL and scintillation spectra at around 890, 1060, and 1300 nm. The 5.0% Nd-doped sample showed the highest PL quantum yield of 49.5%. In addition, the 5.0% Nd-doped sample had the highest scintillation intensity under X-ray irradiation among the samples, and the lowest detectable dose rate was 0.001 Gy/h.

Comparative Validation of Scintillator Materials for X-Ray-Mediated Neuronal Control in the Deep Brain

When exposed to X-rays, scintillators emit visible luminescence. X-ray-mediated optogenetics employs scintillators for remotely activating light-sensitive proteins in biological tissue through X-ray irradiation. This approach offers advantages over traditional optogenetics, allowing for deeper tissue penetration and wireless control. Here, we assessed the short-term safety and efficacy of candidate scintillator materials for neuronal control. Our analyses revealed that lead-free halide scintillators, such as Cs3Cu2I5, exhibited significant cytotoxicity within 24 h and induced neuroinflammatory effects when injected into the mouse brain. In contrast, cerium-doped gadolinium aluminum gallium garnet (Ce:GAGG) nanoparticles showed no detectable cytotoxicity within the same period, and injection into the mouse brain did not lead to observable neuroinflammation over four weeks. Electrophysiological recordings in the cerebral cortex of awake mice showed that X-ray-induced radioluminescence from Ce:GAGG nanoparticles reliably activated 45% of the neuronal population surrounding the implanted particles, a significantly higher activation rate than europium-doped GAGG (Eu:GAGG) microparticles, which activated only 10% of neurons. Furthermore, we established the cell-type specificity of this technique by using Ce:GAGG nanoparticles to selectively stimulate midbrain dopamine neurons. This technique was applied to freely behaving mice, allowing for wireless modulation of place preference behavior mediated by midbrain dopamine neurons. These findings highlight the unique suitability of Ce:GAGG nanoparticles for X-ray-mediated optogenetics. The deep tissue penetration, short-term safety, wireless neuronal control, and cell-type specificity of this system offer exciting possibilities for diverse neuroscience applications and therapeutic interventions.

Quercetin regulates sensitivity to X-ray radiation of hepatocellular carcinoma through miR-216a-3p

Hepatocellular carcinoma (HCC) is a highly aggressive liver cancer with limited therapeutic options, and enhancing radiosensitivity remains a key challenge in improving treatment outcomes. Quercetin (Que) can inhibit the progression of hepatocellular carcinoma (HCC); however, its effect on HCC radiosensitivity remains unclear. This research investigates the role of Que in regulating HCC growth and radiosensitivity, aiming to provide a scientific foundation for enhancing the clinical efficacy of radiation therapy in HCC. The CCK-8 assay was used to determine the optimal treatment conditions for Que and X-rays. Changes in cell growth, cycle arrest, invasion, migration, the relative proportion of JC-1 red and green fluorescence (mitochondrial membrane potential), and the levels of ROS, MDA, SOD, and GSH-Px (oxidative stress) were assessed using flow cytometry, Transwell assays, JC-1 staining, Western blot, and ELISA, respectively, under Que, X-ray, and co-treatment conditions. The effect of miR-216a-3p knockdown on the action of Que was also explored, and the potential pathways by which Que regulates HCC growth and radiosensitivity were investigated in conjunction with in vivo subcutaneous transplantation tumor experiments. The in vitro treatment parameters for Que and X-rays were 100 µM and 4 Gy. Que combined with X-ray therapy enhanced HCC cell radiosensitivity, reduced proliferation, invasion, and migration, and promoted oxidative stress and apoptosis. Que was found to upregulate miR-216a-3p in HCC cells. Rescue experiments with miR-216a-3p knockdowns demonstrated that Que regulates HCC cell radiosensitivity via miR-216a-3p. In vivo research further showed that Que increased tumor sensitivity to X-rays by upregulating miR-216a-3p, thereby inhibiting HCC growth. In conclusion, Que has been shown to enhance HCC radiosensitization by upregulating miR-216a-3p and inhibiting HCC progression. Que may be a promising agent for increasing the radiosensitivity of HCC.

Enhancing low-energy X-ray excited afterglow in lanthanide-doped fluoride core@shell nanoparticles for autofluorescence-free imaging

Lanthanide-doped fluoride nanoparticles (NPs) exhibit tunable X-ray excited afterglow (XEA), holding great promise for autofluorescence-free flexible X-ray imaging. However, materials with low atomic numbers, while sensitive to low-energy X-ray photons, suffer from weak X-ray absorption coefficients. This poses a significant challenge in achieving high-performance XEA with minimized radiation risk. In this study, we enhance the low-energy XEA of lanthanide activators by engineering the interfacial defect formation energy (Ef) in CaF2-based heterogeneous core/shell nanoarchitectures. Mechanistic investigations demonstrate that a large lattice misfit between the core and shell reduces the interfacial defect Ef, facilitating the formation of Frenkel defects and significantly increasing XEA intensity after low-energy X-ray irradiation. Specifically, the heterogeneous CaF2:Tb@CaLuF5 core/shell NPs, with a misfit of 3.382 %, exhibit approximately ∼ 8.9 times higher XEA intensity compared to the CaF2:Tb@CaF2 homogeneous core/shell NPs at 10 kV. Furthermore, integrating the CaF2:Tb@CaLuF5 NPs into a flexible scintillation screen enables XEA-based delayed imaging with high spatial resolution, up to approximately 14.2 lp mm−1, and an autofluorescence-free background. These findings advance the development of superior low-energy XEA materials and pave the way for autofluorescence-free three-dimensional X-ray imaging.

Bio-prospecting the Anti-oxidative and Radioprotective Role of Bioactive Pigment Isolated from Pontibacter indicus

Aim: To evaluate the anti-oxidative and radioprotective role of Pontibacter indicus SCG24 pigment during radiation exposure Background: Radiation-induced cytotoxicity is quite common during cancer therapy. There is a need for naturally derived therapeutic molecules that can scavenge free radicals. They may act as substitutes for synthetic molecules. Hence, there is a need for urgent evaluation of these potent compounds before therapeutic application. Objective: The objective of this study is to examine the anti-oxidative and radioprotective role of P. indicus SCG24 pigment, specifically to evaluate free radical scavenging X-ray irradiated HDF cells Method: A radiotoleraent pigment-producing P. indicus SCG24 was isolated from pharmaceutical effluent. Chloroform was used as a primary solvent for pigment extraction. GCMS/MS analysed initial pigment composition. Various In-vitro antioxidant assays were performed using ABTS, FRAP, and DPPH assay. Flow cytometry was used to determine the rate of scavenging activity of pigment in HDF cells. Results: The GCMS/MS profile of the chloroform extract revealed twenty-two compounds. Furthermore, based on the DPPH, ABTS, and FRAP assay, the pigment was found to have significant antioxidant properties. The flow cytometry results indicate that the pigment possesses radioprotectant activity by neutralizing ROS species in HDF cells when exposed to X-ray radiation. Conclusion: These observations on P. indicus SCG24 pigment suggested that the pigment may have potential therapeutic importance.

Improvement of Hygienic and Phytochemical Qualities of Mangosteen (Garcinia Mangostana) Peel by Irradiation

The aim of this study was to compare the effects of gamma ray and x-ray irradiation at different dose levels 95, 10, 15 and 20 kGy) on in mangosteen peel. The antioxidant activities were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP), while total phenolic contents and antibacterial activities against Staphylococcus aureus and Escherichia coli of 60 % ethanolic mangosteen powder extracts were analyzed. The results indicated that both types of ionizing radiations showed a non-significant decrease in measured parameters with increasing doses. The minimum inhibitory concentration (MIC) values of irradiated mangosteen peel extracted against S. aureus and E. coli ranged from 0.125 to 2.0 mg/mL. The quantity of bioactive compound mangostin determined via high-performance liquid chromatography (HPLC), did not show significant decrease with different irradiation sources and doses. In microbiological aspect, total yeast and mold from both irradiation sources were reduced by 1 log cycle after irradiation at 5 kGy. The irradiation induced color changes corresponding to Hunter color L a b value. X-ray irradiation caused slight color alteration compared to gamma rays. The advantage of x-ray irradiation was that it revealed non-significant changes in b values, whereas gamma irradiation showed the significant change in L, and b values with increasing dosage. The x-ray irradiation at the dose 5 kGy effectively decreased microbial contamination while causing minimal changes to phytochemical qualities and color. HIGHLIGHTS Irradiation at 5 kGy was sufficient to control microbial contamination There were no significant changes in antioxidant activities (DPPH, FRAP), a-mangostin contents, total phenolic contents (TPC) and antibacterial activities: after irradiation up to 20 kGy X-ray irradiation was an excellent alternative to gamma irradiation for decontamination with a non-significant alteration in b values. GRAPHICAL ABSTRACT

Anti irradiation nanoparticles shelter immune organ from radio-damage via preventing the IKK/IκB/NF-κB activation

BackgroundNormal tissue and immune organ protection are critical parts of the tumor radiation therapy process. Radiation-induced immune organ damage (RIOD) causes several side reactions by increasing oxidative stress and inflammatory responses, resulting in unsatisfactory curability in tumor radiation therapy. The aim of this study was to develop a novel and efficient anti irradiation nanoparticle and explore its mechanism of protecting splenic tissue from radiation in mice.MethodsNanoparticles of triphenylphosphine cation NIT radicals (NPs-TPP-NIT) were prepared and used to protect the spleens of mice irradiated with X-rays. Splenic tissue histopathology and hematological parameters were investigated to evaluate the protective effect of NPs-TPP-NIT against X-ray radiation. Proteomics was used to identify differentially expressed proteins related to inflammatory factor regulation. In addition, in vitro and in vivo experiments were performed to assess the impact of NPs-TPP-NIT on radiation therapy.ResultsNPs-TPP-NIT increased superoxide dismutase, catalase, and glutathione peroxidase activity and decreased malondialdehyde levels and reactive oxygen species generation in the spleens of mice after exposure to 6.0 Gy X-ray radiation. Moreover, NPs-TPP-NIT inhibited cell apoptosis, blocked the activation of cleaved cysteine aspartic acid–specific protease/proteinase, upregulated the expression of Bcl-2, and downregulated that of Bax. We confirmed that NPs-TPP-NIT prevented the IKK/IκB/NF-κB activation induced by ionizing radiation, thereby alleviating radiation-induced splenic inflammatory damage. In addition, when used during radiotherapy for tumors in mice, NPs-TPP-NIT exhibited no significant toxicity and conferred no significant tumor protective effects.ConclusionsNPs-TPP-NIT prevented activation of IKK/IκB/NF-κB signaling, reduced secretion of pro-inflammatory factors, and promoted production of anti-inflammatory factors in the spleen, which exhibited radiation-induced damage repair capability without diminishing the therapeutic effect of radiation therapy. It suggests that NPs-TPP-NIT serve as a potential radioprotective drug to shelter immune organs from radiation-induced damage.

Characterization of latent image of electron beam resist via critical-dimension resonant soft X-ray scattering

Characterization of latent image of electron beam resist via critical-dimension resonant soft X-ray scattering

Wavelet analysis of low-frequency quasi-periodic oscillations in MAXI J1803−298 observed with Insight-HXMT and NICER

Abstract With data observed by the Hard X-ray Modulation Telescope (Insight-HXMT) and the Neutron star Interior Composition Explorer (NICER), we study low-frequency quasi-periodic oscillations (LFQPOs) of the black hole candidate MAXI J1803−298 during the 2021 outburst. Based on hardness intensity diagram and difference of the QPOs properties, Type-C and Type-B QPOs are found in the low-hard state and soft intermediate state, respectively. After searching for and classifying QPOs in Fourier domains, we extract the QPO component and study it with wavelet analysis. The QPO and no-QPO time intervals are separated by the confidence level, so that the S-factor, which is defined as the ratio of the QPO time interval to the total length of good time interval, is calculated. We found S-factors decrease with QPOs frequency for Type-C QPOs but stay stable around zero for Type-B QPOs. The relation of S-factor of Type-C QPOs and photon energy, the correlation of S-factor and counts are also studied. Different correlation of S-factor and counts for different energy bands indicates different origins of QPOs in high energy and low energy bands, which may be due to a dual-corona scenario.

Role and mechanism of KIAA1429 in regulating cellular ferroptosis and radioresistance in colorectal cancer.

Colorectal cancer (CRC) is one of the most common non-cutaneous malignancies, causing significant mortality and a substantial burden. This study aims to explore the role of KIAA1429 (also known as vir-like m6A methyltransferase associated [VIRMA]) protein in the radioresistance of CRC. CRC cells and a radioresistant cell line were cultured, and KIAA1429 expression was detected. After the down-regulation of KIAA1429, its effect on the radioresistance and ferroptosis of cancer cells was analyzed. The role of ferroptosis in radioresistance was verified. The binding relationship among long non-coding RNA endogenous Bornavirus-like nucleoprotein 3, pseudogene (lncRNA EBLN3P), microRNA (miR)-153-3p, and KIAA1429 was analyzed. KIAA1429 and lncRNA EBLN3P were highly expressed in CRC, while miR-153-3p was poorly expressed. KIAA1429 and lncRNA EBLN3P were further increased/decreased in the radioresistant cells. KIAA1429 knockdown decreased the survival rate of the radioresistant cell line after X-ray irradiation and increased gamma H2A histone family member X (γ-H2AX), ferroptosis, and oxidative stress. A ferroptosis inhibitor alleviated the inhibitory effect of KIAA1429 knockdown on radioresistance. KIAA1429-mediated m6A modification up-regulated lncRNA EBLN3P, and lncRNA EBLN3P increased KIAA1429 by competitively binding to miR-153-3p. miR-153-3p silencing or lncRNA EBLN3P overexpression attenuated the promotion of ferroptosis and the inhibition of radioresistance induced by KIAA1429 knockdown. Overall, KIAA1429-mediated m6A modification up-regulated lncRNA EBLN3P expression, and lncRNA EBLN3P increased KIAA1429 expression by competitively binding to miR-153-3p, thus reducing ferroptosis and increasing the radioresistance of CRC.

Hard X-ray Photoelectron Spectroscopy Probing Fe Segregation during the Oxygen Evolution Reaction.

NiFe electrocatalysts are among the most active phases for water splitting with regard to the alkaline oxygen evolution reaction (OER). The interplay between Ni and Fe, both at the surface and in the subsurface of the catalyst, is crucial to understanding such outstanding properties and remains a subject of debate. Various phenomena, ranging from the formation of oxides/(oxy)hydroxides to the associated segregation of certain species, occur during the electrochemical reactions and add another dimension of complexity that hinders the rational design of electrodes for water splitting. In this work, we have developed the procedure for the quantification of chemical depth profiling by XPS/HAXPES measurements and applied it to two NiFe electrodes with different porosities. The main outcome of this study is related to the surface reconstruction of the electrodes during the OER, followed at two different depths by means of X-ray photoelectron spectroscopy. We find that Fe initially segregates at the surface when exposed to ambient conditions, resulting in the formation of an inactive FeOx phase. In addition, the porosity of the catalyst plays a significant role in the segregation process and thus in the performance of the electrode. In particular, the higher porosity of the nanostructured sample is responsible for a more pronounced diffusion of Fe from the subsurface to the surface with a more effective suppression of the activity of the Ni1-xFexOOH phase. These results highlight the importance of the fact that the chemical state of the surface of a multielement system is a snapshot in time, dependent on both external parameters, such as the applied potential and the adjacent electrolyte, and the underlying bulk properties accessible with HAXPES.