Browse Articles

Experimental characterization of proton minibeam therapy delivery under FLASH dose-rate conditions

Abstract Proton minibeam radiation therapy (pMBRT) introduces spatial fractionation of dose distributions at submillimeter resolution, offering a promising approach to reducing normal tissue toxicity while maintaining effective tumor control. However, the high monitor unit (MU) requirements of multi-slit collimators (MSC) result in extended delivery times, posing a significant challenge. This study explores the feasibility of integrating pMBRT with ultra-high-dose-rates (UHDR) to overcome this limitation while leveraging potential biological synergies to enhance the therapeutic index and advance clinical applications. The study utilized the IBA ProteusONE compact proton therapy system equipped with two MSCs, each with center-to-center distances of 2.8 mm, slit widths of 1.0 mm, and thicknesses of 6.5 cm and 10 cm. UHDR delivery was achieved with 228 MeV protons at a current of 125 nA, while clinical beams operated at 226 MeV with 1–5 nA. Dose measurements using Gafchromic films in solid water phantoms were compared with Monte Carlo simulations. Delivery times were compared for FLASH and clinical beams. PBS dose rate was calculated based on the spot delivery log file. The study successfully demonstrated pMBRT dose distributions under UHDR, significantly reducing treatment times to 2.5 s compared to 3 min for clinical beams. The 10 cm collimator achieved higher peak-to-valley dose ratios (PVDRs) at 2 cm depth (4.36) than the 6.5 cm collimator (2.57), optimizing UHDR delivery conditions. Results highlight the potential to improve dose delivery efficiency while maintaining spatial resolution and dose modulation, supporting future clinical advancements. This study demonstrates the feasibility of integrating pMBRT with UHDR using a clinical proton therapy system. By addressing challenges associated with delivery times and leveraging the combined advantages of spatial fractionation and ultra-high-dose-rates, this work paves the way for the clinical translation of pMBRT with UHDR, offering innovative possibilities for treating challenging malignancies with high-dose precision therapy.

Ultrasound wrist mapping to develop a noninvasive radiation detector for dynamic positron emission tomography

Abstract Quantitative PET studies require a measurement of the arterial input function (AIF), the time-dependent radiotracer concentration in arterial blood plasma. Several groups are developing non-invasive detectors to measure the AIF from the radial artery. This study quantifies the depth and cross-sectional area of the radial artery and accompanying veins at different wrist positions using ultrasound. These anatomical data will guide the design of a non-invasive, wrist-worn detector for AIF acquisition—a practical, patient-friendly alternative to invasive blood sampling. Ultrasound imaging of the wrist was performed on 154 healthy individuals at specified distances from the distal wrist crease (2 cm , 4 cm , and 6 cm ). The depths of the radial artery at distances of 2 cm , 4 cm , and 6 cm from the distal wrist crease are 3.36 (1.25) mm , 4.08 (1.81) mm , and 4.66 (2.23) mm , respectively (mean (SD)). Similarly, the cross-sectional areas of the radial artery at these distances are 4.23 (1.75) mm $$^{2}$$ , 3.92 (1.71) mm $$^{2}$$ , and 3.90 (1.88) mm $$^{2}$$ , respectively. The radial artery becomes larger and more superficial near the wrist, suggesting a radiation detector be placed 2 cm from the distal wrist crease on the left arm, where it is generally more superficial than on the right.

Contribution of family Support, illness perception, and psychological factors to fluid management behaviors in peritoneal dialysis patients

One-year body weight loss and gain as independent predictors of frailty-related outcomes and mortality in an aging Japanese population

Experimental study of multiple-shot unitary channels discrimination using the IBM Q computers

Abstract Tasks involving black boxes appear frequently in the theory of quantum information, with quantum channel discrimination as a central example that has been deeply studied. In this work, we experimentally study the discrimination between two unitary quantum channels in the multiple-shot scenario. We challenge the theoretical results concerning the probability of correct discrimination with the results collected from experiments performed on the IBM Brisbane. Our analysis shows that neither too deep quantum circuits nor circuits that create too much entanglement are suitable for the discrimination task. We conclude that circuit architectures which minimize entanglement overhead while preserving discrimination power are significantly more resilient to hardware noise if their depth does not exceed a threshold value. Consequently, our findings necessitate a paradigm shift: for execution on noisy hardware, the theoretically suboptimal circuit is, counterintuitively, often the superior choice.

GEMS satellite data fusion for hourly air quality prediction in Taiwan

A comparative analysis of embedded chatbot models and ChatGPT-4 for answering orthodontic treatment queries

Regional variations in serum pepsinogen levels and their influencing factors: a multi-center cross-sectional study

Abstract Serum pepsinogen (PG) levels are recognized biomarkers influenced by various factors, including lifestyle, Helicobacter pylori ( H. pylori ) infection status, and the presence of gastric mucosal lesions. However, whether baseline serum PG levels exhibit regional heterogeneity independent of concurrent gastric mucosal lesions has not been clearly established. The study aims to investigate the variability of baseline serum PG levels and identify potential influencing factors across China. Data were collected from individuals undergoing routine health checkups at twelve collaborating medical centers across China between October 2016 and October 2021. Serum pepsinogen I (PGI) and pepsinogen II (PGII) were measured and the pepsinogen I/II ratio (PGR) was calculated; gastroscopy with histopathology was performed to define gastric mucosal status. Detection of H. pylori infection status was performed using histology, serology, and/or breath tests. Lifestyle factors were obtained via standardized questionnaires. Regional differences and associated factors were evaluated using t-tests/ANOVA and multivariable linear regression (Stata 18). A total of 2902 individuals were included in the study. Of them, 2382 was classified as non-atrophic gastritis (NAG), and their regional distribution varied. Baseline serum PG levels significantly varied by regions, except between Southern and Central China. Factors such as H. pylori -positive (including prior eradication), high salt intake, and frequent fruit consumption were significantly associated with baseline serum PGR levels nationwide, with β value (95%CI) being − 2.75 (-3.33, -2.17), 1.66 (0.89, 2.44), and − 2.14 (-2.78, -1.51), respectively. Further analysis stratified by H. pylori infection status showed that both high salt and frequent fruit intake remained significantly associated with PGR. Baseline serum PG levels, independent of gastric mucosal lesions, exhibit significant regional variations across China. These variations are primarily associated with H. pylori infection status and dietary factors. Our findings suggest that region-specific and H. pylori -stratified PG cut-off values may be warranted for gastric cancer (GC) screening, pending prospective validation.

A novel human acute myeloid leukemia cell line SDEY-AML1 with KMT2A: MLLT3, IKZF1: EVX1 fusions exhibits high tumorigenicity in NSG mice

Computational optimization of DEK1 calpain domain solubility through integrated structural modelling and data-driven targeted mutagenesis

An intertwined triple-bottom-line rating system for highway sustainability in developing countries

Abstract Highway sustainability evaluation is a crucial step towards ensuring that transportation infrastructure meets the environmental, social, and economic needs of societies. While previous studies have developed frameworks for the sustainability performance of highway projects, they did not comprehensively address all sustainability aspects, nor stages of these projects. Furthermore, the Sustainable Development Goals (SDGs) related to highways were almost overlooked in most previous studies and infrastructure rating systems. Thus, this study introduces a rating system (RS) that encompasses the most significant factors influencing highway sustainability in Egypt across the three sustainability dimensions. These factors were identified through a comprehensive analysis of previous studies, SDGS, and existing infrastructure rating systems. A questionnaire survey was designed to assess the impact of various factors on highway sustainability. Statistical analyses were carried out to summarize data into a smaller set of factors, identifying 18 factors that were weighted using the analytic hierarchy process method. This model was then applied to real-life case studies in Egypt, and the results were compared with the Envision RS. The results’ convergence confirmed the validity of the developed RS, which features fewer factors and a more user-friendly interface. Finally, the developed RS was reviewed by highway experts and environmental consultants to assess its performance and gather their recommendations. The developed RS presents a summary report that identifies shortcomings in achieving the target score and offers guidelines to enhance the sustainability score. Also, it addresses the shortcomings found in other RSs, providing a more balanced approach across the investigated sustainability dimensions.

Experimental study on dynamic mechanical properties and damage mechanisms models of concrete under freeze-thaw cycles

Optimization and mechanistic insights into SiO2 nanoparticle–CTAB surfactant pickering emulsions for water mobility control

Computational identification of multi-target natural compounds from Sesbania grandiflora as potential therapeutic agents against Klebsiella pneumoniae

Working face status detection in coal mine based on YOLOv8-EST

Isotherm, kinetic, and thermodynamic insights into textile effluent remediation using acid-treated sugarcane peel

Existence and stability of time-fractional Keller-Segel-Navier-Stokes system with Poisson jumps

Clinical efficacy and cost-effectiveness analysis of mobile health interventions in diabetes care: a systematic review and meta-analysis

Scaled up fed-batch production of recombinant alpha-1-antitrypsin by CHO cells in single-use surface aerated orbital shaken bioreactor

Abstract Augmentation therapy is a treatment option available in the market that has been approved by the U.S. Food and Drug Administration (FDA) for alpha-1-antitrypsin (A1AT) deficient patients. The treatment requires weekly injections of purified A1AT for the patients and relies on plasma donor. The demand for A1AT is also high due to its functional role in various diseases. However, scaling up production of purified human plasma A1AT remained costly and challenging. It is therefore of great interest to generate A1AT at larger scale in ensuring a consistent supply to the market. In this paper, we evaluated the stability and productivity of ten Chinese Hamster Ovary (CHO) single cell clones over 12 weeks. This was followed by scaling up the fed-batch production of A1AT with the selected cell clone in a 10L single-use surface aerated orbital shaken bioreactor SB10-X. The cell specific productivity of the two bioreactor runs were at 9.6 and 12 pg/cell/day (pcd) respectively, which were comparable to shake flasks. While the paper focuses on the possibility to scale up A1AT production, process conditions such as feeding regime could be investigated to further prolong the culture longevity and increase productivity.

Uncovering Cas9 PAM diversity through metagenomic mining and machine learning