Extreme Light Infrastructure - Nuclear Physics

Exploring accurate and noninvasive methods for detecting pulmonary hypertension (PH) has always been a focal point of research. Owing to its exceptional spatiotemporal resolution, magnetocardiography (MCG) has demonstrated potential value in cardiovascular diseases. This exploratory study aims to investigate the characteristics of MCG variations in PH patients and evaluate their potential utility in distinguishing healthy subjects from those with PH. This study analyzed 175 PH patients and 333 healthy subjects who underwent MCG examination. The training cohort consisted of patients with PH previously diagnosed by right heart catheterization (RHC) and age-frequency-matched healthy controls (HC). The testing cohort comprised age- and frequency-matched HC and PH patients who underwent both MCG and RHC on the same day. Nine MCG parameters were included. Logistic regression was used to screen for significant parameters and develop a model. By comparing the pseudo-current density maps, it was found that the current vector at the R-wave peak of HC points toward the lower-left quadrant, whereas in PH patients, it points toward the lower-right quadrant. The MCG detection model demonstrated robust performance, achieving a sensitivity of 86.1% and a specificity of 94.1% in the testing cohort. Compared to the ECG of PH patients, MCG demonstrated greater sensitivity; however, it exhibited slightly lower specificity. Furthermore, MCG can detect PH in patients with normal ECG findings. MCG demonstrates highly promising potential for the noninvasive detection of PH.

Laser-induced autofluorescence (LIAF) spectroscopy is a label-free optical technique sensitive to biochemical and structural tissue properties. Its application in upper aerodigestive tract malignancies is in its early stages. This study evaluates the feasibility of a matrix scan-based LIAF approach for examining differences between normal and malignant tissues. An exploratory case series involving three patients with oropharyngeal malignancies was conducted. Tissue sections from normal and tumor regions were analyzed using LIAF spectroscopy, including intensity and lifetime measurements, implemented through a matrix scanning protocol with fixed excitation, detection sensitivity, and sample thickness. Complementary Fourier-transform infrared (FTIR) spectroscopy was used to qualitatively assess biochemical variations, and spectroscopic findings were correlated with histopathological evaluation. Within individual cases, consistent differences in autofluorescence spectral and lifetime characteristics were observed between benign and malignant tissue regions. FTIR analysis revealed concurrent biochemical variations that qualitatively supported the autofluorescence observations. This exploratory study demonstrates the potential of combining LIAF matrix scan with FTIR spectroscopy to investigate tissue-specific spectral variations in upper aerodigestive tract lesions. The findings are preliminary and motivate further investigation using larger patient groups and clinically relevant acquisition conditions.

A state-of-the-art microscopic global nucleon-nucleus optical potential has been developed by Whitehead, Lim, and Holt (WLH) within the framework of many-body perturbation theory, incorporating realistic nuclear interactions derived from chiral effective field theory. Given its potentially greater predictive power for reactions involving exotic isotopes, we apply it to the calculations of astrophysical neutron-capture reactions for the first time, which are particularly important to the nucleosynthesis of elements heavier than iron. It is found that this potential provides a good description of experimental known neutron-capture cross sections and Maxwellian-averaged cross sections. For unstable neutron-rich nuclei, we comprehensively calculate the neutron-capture reaction rates for all nuclei with 26 ≤ Z ≤ 84, located between the valley of stability and the neutron drip line, using the backward-forward Monte Carlo method with the f rms deviation as the χ 2 estimator. The results reveal a noticeable separation in the uncertainty of rates around an isospin asymmetry of 0.28 under the constraint f rms ≤ 1.56. This highlights the critical role of isospin dependence in optical potentials and suggests that future developments of the WLH potential may pay special attention to the isospin dependence.

Identifying reliable, nondestructive indicators of electrolyte degradation is essential for advancing the diagnostics and lifetime assessment of lithium-ion batteries. In this study, we performed multinuclear nuclear magnetic resonance spectroscopy at various time points during systematic degradation of battery electrolyte components undergoing thermal cycling. We highlight a strong correlation between electrolyte degradation state and the 7Li nuclear spin polarization lifetime, while other nuclei did not respond as strongly. A mechanistic rationale for this phenomenon is provided using molecular dynamics simulations. The remarkable sensitivity of 7Li nuclear spin lifetime to electrolyte health underscores its potential value as a nondestructive, field-independent probe suited for diagnosing defects and evaluating the overall health of lithium-ion batteries.

Nanostructured targets showed improved interaction with ultra-intense laser pulses in comparison to planar ones, both in simulations and in experiments. By increasing the surface area, the absorption and conversion efficiency of the laser energy to the accelerated particle energy are enhanced due to volumetric heating, leading to advanced proton acceleration, x-ray emission, ultra-high energy density matter creation, and terabar pressure generation. This work is focused on exploring the limits of the electrodeposition methods for the fabrication of nanostructured targets suitable for ultra-intense laser experiments at focused intensities as high as 1023W/cm2. The geometrical characteristics of the nanostructures are expanded to meet a wide range of experimental requirements: diameter, length, distance between structures, and substrate thickness. Nickel nanotubes and nanowires on few hundreds nanometer thick substrates were fabricated using porous alumina as template, obtained by aluminium anodization in various electrolyte solutions. The resulting structures revealed diameters and spacing of several hundreds of nanometers, with length varying between 1–10 micrometers, covering homogeneous areas of several square centimetres. The influence of temperature on the current density, with two electrolyte mixtures containing oxalic, citric, phosphoric acids used for anodization, is also reported. In the initial testing using high-power lasers, we found an increase in proton energy by 1.5 times and flux at high-energy tail of the spectrum higher by an order of magnitude, from the nanostructured targets.

In nuclear magnetic resonance (NMR) co-magnetometers, the non-uniform transverse energy distribution of the pumping Gaussian beam can result in substantial optical pumping inhomogeneity and decoherence of atomic spins, which hinder the improvement of the precision and sensitivity of the sensor. One of the most significant recent technological advances for laser beam homogenization is the utilization of the microlens array system. However, the homogenized characteristics of the microlens array system vary with the propagation distance of the pumping light and are not suitable for chip integration, which will affect the sensitivity and compactness of the NMR system. To solve this issue, a metasurface homogenizer is demonstrated for encoding intensity information into the polarization profile of an incident Gaussian beam by combining the geometric phase and Malus’ law with the transverse intensity distribution independent of the propagation distance. Compared to Gaussian beam pumping at identical input power, the metasurface homogenizer enhances the measured optical magnetic sensitivity by 23%. The proposed metasurface homogenizer not only realizes the higher precision and sensitivity in NMR co-magnetometers, but also highlights how metasurface-based technologies can contribute to the integrated quantum sensing regime.