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Feasibility of a Tungsten-181 HDR brachytherapy source: Analysis of isotope production and source dosimetry.

BACKGROUND: Interest in Intensity Modulated Brachytherapy (IMBT) for High Dose Rate Brachytherapy (HDR) treatments has steadily increased in recent years. However, intensity modulation is not best optimized for currently used HDR sources since they emit high energy photons. To that end, the focus on IMBT has moved to middle energy sources, such as Ytterbium-169; yet even Yb-169 emits some high energy photons at a low yield. We present an alternative isotope, Tungsten-181 (T1/2 = 121 days) that is interesting due to its complete lack of high energy photon emissions. (Eavg = 58.9 keV, Emed = 57.

Predicting radiotoxic effects after BNCT for brain cancer using a novel dose calculation model.

PURPOSE: The normal brain is an important dose-limiting organ for brain cancer patients undergoing radiotherapy. This study aims to develop a model to calculate photon isoeffective doses (DIsoE) to normal brain that can explain the incidence of grade 2 or higher somnolence syndrome (SS⩾2) after Boron Neutron Capture Therapy (BNCT). METHODS: A DIsoE model was constructed to find the reference photon dose that equals the Normal Tissue Complication Probability (NTCP) of the absorbed dose from BNCT. Limb paralysis rates from the rat spinal cord model exposed to conventional or BNCT irradiation we

Rigidity and resistance of larval- and adult schistosomes-medium interface.

Schistosomiasis is second only to malaria in prevalence and severity, and is still a major health problem in many tropical countries worldwide with about 200-300 million cases and with more than 800 million people at risk of infection. Based on these data, the World Health Organization recommends fostering research efforts for understanding at any level the mechanisms of the infection and then decreasing the social and economical impact of schistosomiasis. A key role is played by the parasite apical lipid membrane, which is entirely impervious to the surrounding elements of the immune system.

Metrology, Standards, and Mission: Synopsis of the 2026 Annual Meeting of the Council on Ionizing Radiation Measurements and Standards (CIRMS).

The Council on Ionizing Radiation Measurements and Standards (CIRMS) is an independent, non-profit council composed of experts from academia, government, and industry across all areas of ionizing radiation science and technology, providing leadership, focus, and coordinated action on emerging radiation metrology needs. This mission is achieved through the organization of an annual scientific conference and the periodic publication of a Needs Report which identifies priority areas in ionizing radiation measurements and standards. This article summarizes the outcomes from the CIRMS 2026 meeting

Design and characterization of eco-friendly phospho-silicate glasses modified with TiO2 in the CaO-MgO-P2O5-SiO2 system for radiation shielding protection.

The primary objective of this work is to develop eco-friendly and cost-effective glasses for radiation shielding. The phosphosilicate non-crystalline materials were prepared based on the 30CaO-(20-X)MgO-XTiO2-5P2O5-45SiO2 glass system (where X = 0, 1.0, 2.0, 4.0, and 6.0 mol%). The effect of adding various TiO2 contents on physical properties, optical power, and radiation mitigation efficiency was studied. XRD examination established the vitreous nature of all investigated samples. The results showed that the density, oxygen packing density, and field strength improved with increased TiO2 cont

Optimal binning of correlated measurements.

Experimental measurements are commonly represented on a discrete grid, requiring a balance between granularity and statistical noise. Two strategies have traditionally been used to improve such representations: selecting an appropriate bin width to control discretization error and applying kernel-based smoothing to suppress fluctuations. Despite their shared goal, these approaches have largely developed independently, without a unified statistical description of how discretization and correlation jointly determine measurement precision. Here, we extend the discussion of optimal interval averag

Kinetically Controlled Assembly of Janus-Structured Nanobubble-Lipid Nanoparticles via Ultrasonic Micromixing.

Controlling the internal architecture and morphology of lipid nanoparticles (LNPs) beyond their size remains a central challenge in nanoparticle engineering. Conventional micromixer-based assembly methods provide rapid mixing but lack the temporal resolution to manipulate the multiple competing kinetic processes that occur during LNP self-assembly. Here, we demonstrate kinetically controlled fabrication of Janus-structured surface nanobubble-lipid nanoparticles (SNB-LNPs) using an ultrasonic micromixer that enables independent tuning of three critical time scales: mixing time (t m), bubble gen

Structure analysis of liquid bismuth using molecular dynamics simulation.

Liquid bismuth (Bi) exhibits an anomalous local structure that cannot be described by the hard-sphere model. It features a subpeak near 3in the structure factor and a shoulder over the range of 4 Å-5.5 Å in the pair distribution function. This anomaly is associated with the Peierls distortion in the crystalline A7 structure. This study aims to clarify the structural origin in liquid Bi by comparing the liquid structure with the A7 structure via molecular dynamics (MD) simulations using a machine learning potential. The MD simulation performed at 573 K reproduced the static anomalies and the dy

The central role of radiotherapy in remodeling the tumor immune microenvironment: mechanisms and therapeutic implications.

Radiotherapy is an essential component of multidisciplinary cancer treatment. Its role has expanded from conventional local tumor eradication to active regulation of the tumor immune microenvironment. In recent years, emerging radiotherapy strategies, including FLASH radiotherapy, boron neutron capture therapy, lattice radiotherapy, spatially fractionated radiation therapy, precision particle therapy, immunomodulatory stereotactic body radiotherapy, and immune-optimized carbon ion therapy, have provided new opportunities to improve tumor control, reduce normal tissue toxicity, and overcome rad

Alginate Aerogels Crosslinked with Isophorone-Based Polyurea: The Missing Link between Rigid Aromatic and Flexible Aliphatic Nanostructured Networks.

Polyurea-cross-linked alginate (X-Ca-alg-IP) aerogels, prepared from calcium alginate (Ca-alg) gels and the isocyanurate trimer of rigid aliphatic isophorone diisocyanate (IP), provide insight into the role of the cross-linker molecular structure in the nanoscale and macroscopic properties of X-biopolymer aerogels. Keeping all other synthetic conditions the same, the polyurea (PUA) loading in X-Ca-alg-IP (40-46% w/w) was lower than what was obtained using flexible aliphatic (56% w/w) or rigid aromatic (60% w/w) triisocyanate monomers, reflecting differences in monomer reactivity and packing ef

Cosurfactant-Mediated Interfacial Flexibility: A Key to Controlling the Morphology of Anisotropic Nanostructures in Cetyltrimethylammonium Bromide Reverse Micelles.

Reverse micelles (RMs) have emerged as versatile soft templates for engineering anisotropic nanostructures. However, insights into how cosurfactant-mediated interfacial flexibility governs morphology remain limited, even though this parameter is critical for the rational design of anisotropic nanomaterials. In this study, we examine how cosurfactant-mediated interfacial dynamics in cetyltrimethylammonium bromide (CTAB)-based RMs direct the growth of copper oxalate (CuOx) nanostructures. By employing two distinct cosurfactants-1-butanol and 1-octanol-we demonstrate a morphology switch from nano

Structure-function relationship of a single double bond: the difference in lamellar phase behaviors between ceramides NS and NdS.

The barrier function of mammalian skin is closely related to the unique structure of the complex lipid matrix of the stratum corneum. Within this matrix, the heterogeneous group of ceramides plays a key role in determining barrier properties. As native stratum corneum is highly complex, simplified stratum corneum lipid mixture models can be used to efficiently elucidate their detailed structural arrangement. Here, the application of selected ceramide subspecies with defined chain lengths and head group structures in monomeric lipid mixture models, i.e. containing only a single ceramide subspec

Ice-induced structural reconfigurations in nanoconfined water-glycerol mixtures.

We elucidated the mesoscopic organization emerging in water-glycerol mixtures confined within the nanoporous cylindrical pores of SBA-15 and MCM-41 silicas, with pore diameters of 8.1 and 3.5 nm, respectively. Neutron diffraction was used to track variation in the intensity of Bragg reflections originating from the crystalline pore arrangements after filling and as a function of composition and temperature. In addition, isotopic substitution was employed to systematically adjust the scattering length density contrast between the different components of the mixtures. The radial concentration pr

ADMET-Guided Design and In Silico Planning of Boron Delivery Systems for BNCT: From Transport and Biodistribution to PBPK-Informed Irradiation Windows.

BNCT (Boron Neutron Capture Therapy) is a binary radiotherapeutic modality in which high LET (Linear Energy Transfer) particles are generated from 10B(n,α)7Li reaction, ideally within boron-loaded tumour cells, so the therapeutic outcome depends critically on the pharmacokinetics and biodistribution of boron carriers. In this review, boron-containing agents for BNCT, with a focus on ADMET (absorption, distribution, metabolism, excretion and toxicity) and model-informed design, were examined. Low-MW (low-molecular-weight) compounds, peptide conjugates, polymeric and nanostructured platforms and

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… Introduction BNCT (Boron Neutron Capture Therapy) is a binary radiotherapeutic modality [ 1 , 2 , 3 ] predicated on the nuclear reaction between 10 B (boron-10) and low-energy thermal neutrons. … Recent Progress of Nano-Drugs in Neutron Capture Therapy Theranostics 2024 14 3193 3212 10.7150/thno.95034 38855185 PMC11155403 7. Coghi P. Li J. Hosmane N.S. Zhu Y. Next Generation of Boron Neutron Capture Therapy (BNCT) Agents for Cancer Treatment Med. Res. …

Atomic-scale double-slit interferometry with a focused electron probe.

Since Young's original work with light1, double-slit interference experiments have been paradigmatic demonstrations of wave-particle duality2-6. They now underpin modern electron, neutron, atom and molecule interferometers, whose fringe visibility and phase encode quantitative information about both the wave and the diffracting object. Extending this to atomic length scales would offer direct, local access to microscopic structure and dynamics, but has remained unexplored. Here we show that double-slit interferometry can be realized at atomic scales inside a crystal. Using scanning transmissio

Magnetic Anisotropy in the Homoleptic [CoX4]2- (X = Cl, Br, I) Series: Spectroscopic Determination and Ligand Field Studies.

Four-coordinate transition metal complexes with unpaired electrons (S ≥ 1) typically exhibit structures deviated from perfect Td geometry, leading to magnetic anisotropy. (NEt4)2[CoX4] (X = Cl, Co-Cl; Br, Co-Br; I, Co-I) with pseudotetrahedral structures are an ideal series to explore how deviation from perfect Td geometry is reflected in magnetic anisotropy. This work presents comprehensive studies of Co-X, including single-crystal X-ray diffraction of Co-Cl and Co-I, measurements of DC and AC magnetic susceptibilities, inelastic neutron scattering (INS), far-infrared magneto-spectroscopy (FI

Minutes-long soft X-ray prompt emission from a compact object merger.

Compact object mergers are multi-messenger sources and known progenitors of some gamma-ray bursts, bright flashes of high-energy radiation powered by a central engine, either an accreting black hole or a neutron star. Our understanding of these events has so far been shaped primarily by observations in the gamma-ray band, leaving their prompt phase poorly constrained at lower energies. A long-lasting (≈100 s) engine-driven X-ray emission was discussed to explain rapidly fading X-ray afterglows following several (≈30%) bursts of short (≲2 s) duration. However, this prompt X-ray component was no

Mercury exposure and Selenium interactions in South American sea lions (Otaria flavescens) from Patagonia, Southwestern Atlantic Ocean.

Mercury (Hg) and selenium (Se) concentrations were analyzed in diverse internal tissues (muscle n = 10, liver n = 10, kidney n = 9 and lung n = 8), and the skin (n = 10) of -the South American sea lion (SASL)-stranded on the beaches of marine protected areas in Patagonia, Argentina. Elemental concentrations (expressed in μg g-1 DW (Dry Weight)) were determined using Instrumental Neutron Activation Analysis (INAA). Mercury accumulated primarily in the liver, followed by the kidney, muscle, lung, and skin. Selenium also showed highest accumulation in the liver, followed by the kidney, lung, musc

Structural divergence in N-terminal domains of AAA proteases paraplegin (SPG7) and FtsH indicates a key structural function in complex formation.

AAA proteases are hexameric ATP-dependent metallopeptidases that perform crucial proteolytic activities within prokaryotic and eukaryotic membranes. Structurally, protomers are comprised of catalytically active C-terminal domains that are anchored to the membrane by an N-terminal autonomous folding unit. In this study, we determined the fold, stability, and oligomeric state of the N-terminal intermembrane domains of human spastic paraplegia type 7 (SPG7)/ paraplegin protein and its bacterial orthologue FtsH using circular dichroism (CD), small-angle X-ray scattering (SAXS), small-angle neutron

Prognosis modelling of adverse events for post-PCI treated AMI patients based on inflammation and nutrition indexes.

OBJECTIVE: This study aimed to evaluate the predictive performance of inflammatory and nutritional indices for adverse cardiovascular events (ACE) in patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI) using a machine learning (ML) algorithm. METHODS: AMI patients who underwent PCI were recruited and randomly divided into non/ACE groups. Inflammatory and nutritional indices were graded according to the laboratory examination reports. Logistic Regression was used to screen for factors that were significant for ML model establishment. The performances