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2025
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- Pub. Date : 2025
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2025
- Book : ()
- Pub. Date : 2025
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2025
Abstract
Methanol is one of the most abundant complex organic molecules in interstellar environments. Molecular lines of its rare isotopologues 12CH3
17OH and 12CH3
18OH therefore play a crucial role in examining the column density of 12CH3
16OH, which serves as a reference for organic molecular chemistry in interstellar clouds. In this study, we have recorded the spectroscopic emission spectrum of 12CH3
17OH in the frequency range between 216 and 264 GHz by making use of an emission-type millimeter and submillimeter spectrometer. We have specifically paid attention to the Q-branch transitions, which are the strongest line series in this frequency region. Among the stable oxygen isotopes, 16O, 17O, and 18O of methanol, only 12CH3
17OH obviously shows line profiles having double and/or triple peaks in low-J transitions, due to the nuclear quadrupole interaction. The newly obtained 12CH3
17OH data will play an important role in facilitating a deeper understanding of the organic chemistry related to star and planet formation. The 12CH3
17OH line data allow us to trace and constrain the isotopic ratio 17O/18O in methanol, which is efficient to investigate the galactic-scale evolution of elements. In addition, we also assigned some transitions of 13CH3
17OH in the recorded spectrum.- Book : 980(1)
- Pub. Date : 2025
- Page : pp.110-110
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2025
- Book : ()
- Pub. Date : 2025
- Page : pp.1-16
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2025
Prostate cancer is a leading cause of cancer-related mortality in men, with radiotherapy (RT) playing a pivotal role in treatment. However, reliable biomarkers for assessing relapse risk following RT remain scarce. This study aimed to evaluate circulating epithelial tumor cells (CETC/CTC) as potential biomarkers for assessing relapse risk in prostate cancer patients undergoing RT. Peripheral blood samples were collected from 52 prostate cancer patients, and CETC/CTC were detected using the EpCAM surface marker. Patients received definitive, adjuvant, or salvage RT, and CETC/CTC counts were measured before, at mid-treatment, and at the end of RT. The association between changes in CETC/CTC counts and relapse risk was examined. CETC/CTC were detected in 96% of patients prior to RT. A significant reduction in CETC/CTC counts during RT, particularly in patients who had undergone surgery, was associated with a lower relapse risk. In contrast, an increase in CETC/CTC counts during or after RT was associated with a higher relapse risk (hazard ratio = 8.8; p = 0.002). Furthermore, 36% of patients receiving adjuvant RT and 14% of those receiving definitive RT relapsed, with a higher risk observed in patients showing increasing CETC/CTC counts during RT. Among patients receiving salvage RT, 18% relapsed, though changes in CETC/CTC counts were less significantly associated with relapse. Monitoring CETC/CTC levels during RT offers important prognostic insights into relapse risk in prostate cancer patients. While changes in CETC/CTC counts correlated with relapse, PSA levels measured during the study did not reliably reflect relapse risk in this cohort. CETC/CTC shows promise as a prognostic marker, though further studies are required to validate its clinical superiority over PSA.- Book : 26(4)
- Pub. Date : 2025
- Page : pp.1548-1548
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2025
Dissociation upon sulfur K-shell excitation or ionization of SF6 is studied by sulfur L-shell emission spectroscopy using synchrotron radiation and multiconfiguration Dirac-Hartree-Fock calculations of emission energies and transition rates. The decay path involves in particular Auger emission with the ejection of one or more electrons, leading to singly or multiply charged intermediate states. Nevertheless, the results of the study show that the observed photon emission at 151–152 eV following excitation at 2485–2489 eV originates dominantly from transitions in neutral sulfur. This clearly indicates that the central atom retains its electrons in a dissociation process where all fluorine atoms detach before the S 2p decay.
Published by the American Physical Society
2025
- Book : 134(6)
- Pub. Date : 2025
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2025
AbstractIt is known that ultrasound-targeted microbubble cavitation (UTMC) can induce vasodilation. This image guided spatially targeted approach is called provascular therapy when used as a radiotherapy sensitizer in radiation oncology. Extracellular adenosine-5’-triphosphate (eATP), which plays an important role in vascular tone regulation, is released by cells following UTMC, possibly through sonoporation (formation of temporary and non-deadly pores in the cell membrane) and/or cell death. Herein, we were interested in quantifying UTMC-mediated ATP releasedin vitrousing a microfluidics-based model and study its relationship with UTMC-mediated cell fate to better understand and improve UTMC mediated bioeffects.Lipid microbubbles (MB, Definity®), luciferin-luciferase (LL – for eATP quantification), and propidium iodide (PI – poration tracer) were flown over HUVEC cells cultured in a microfluidic device. Ultrasounds at 1 MHz, varying in pressure (300, 400 kPa) and length (10, 100, 1000 cycles) were applied to the chip. The LL chemiluminescent signal after the ultrasound pulse was acquired with an EMCCD camera to characterize ATP release kinetics. Then, a viability assay was performed with calcein-AM. An in-house MATLAB program pairing eATP kinetics with PI/calcein data was used to classify cells into three categories (sonoporated, dead, and untreated).Within the testing conditions, a single UTMC pulse caused between 4% and 55% PI-positive (PI+) cells in the ultrasound-treated area. Amongst PI+ cells, we generally found more dead cells than sonoporated cells, except for milder pulses (300 kPa; 10 and 100 cycles). The analysis of individual responses of ATP release demonstrated that dead cells released more ATP (up to 22.4 ± 12.2 fmol/cell) than sonoporated cells (6.8 ± 3.4 fmol/cell) and at a faster release rate which peaked at 4s.This study showed that sonoporation plays a significant role in UTMC-mediated ATP release, advancing our understanding of UTMC’s potential use as a radiosensitizer in solid tumors.- Book : ()
- Pub. Date : 2025
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2025
The family Onocleaceae represents a small family of terrestrial ferns, with four genera and around five species. It has a circumboreal to north temperate distribution, and exhibits a disjunct distribution between Eurasia and North America, including Mexico. Historically, the taxonomy and classification of this family has been subject to debate and contention among scholars, leading to contradictory classifications and disagreements on the number of genera and species within the family. Furthermore, due to this disjunct intercontinental distribution and the lack of detailed study across its wide range, this family merits further study to clarify its distributional pattern. Maximum likelihood and Bayesian phylogenetic reconstructions were based on a concatenated sequence dataset for 17 plastid loci and one nuclear locus, which were generated from 106 ingroup and six outgroup taxa from three families. Phylogenetic analyses support that Onocleaceae is composed of four main clades, and Pentarhizidium was recovered as the first branching lineages in Onocleaceae. Molecular dating and ancestral area reconstruction analyses suggest that the stem group of Onocleaceae originated in Late Cretaceous, with subsequent diversification and establishment of the genera Matteuccia, Onoclea, Onocleopsis, and Pentarhizidium during the Paleogene and Neogene. The ancestors of Matteuccia, Onoclea, and Onocleopsis could have migrated to North America via the Beringian land bridge or North Atlantic land bridge which suggests that the diversification of Matteuccia + Onoclea + Onocleopsis closely aligns with the Paleocene-Eocene Thermal Maximum (PETM). In addition, these results suggest that Onocleaceae species diversity peaks during the late Neogene to Quaternary. Studies such as this enhance our understanding of the mechanisms and climatic conditions shaping disjunct distribution in ferns and lycophytes of eastern Asia, North America, and Mexico and contribute to a growing body of evidence from other taxa, to advance our understanding of the origins and migration of plants across continents.- Book : 14(4)
- Pub. Date : 2025
- Page : pp.510-510
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2025
Abstract
Stochastic fluctuations in the spin frequency ν of a rotation-powered pulsar affect how accurately one measures the power-law braking index, npl, defined through $\dot{\nu }=K\nu ^{n_{\rm pl}}$, and can lead to measurements of anomalous braking indices, with $\vert n \vert = \vert \nu \ddot{\nu }/ \dot{\nu }^{2} \vert \gg 1$, where the overdot symbolizes a derivative with respect to time. Previous studies show that the variance of the measured n obeys the predictive, falsifiable formula $\langle n^{2} \rangle = n_{\rm pl}^{2}+\sigma ^{2}_{\ddot{\nu }}\nu ^{2}\gamma _{\ddot{\nu }}^{-2}\dot{\nu }^{-4}T_{\rm obs}^{-1}$ for $\dot{K}=0$, where $\sigma _{\ddot{\nu }}$ is the timing noise amplitude, $\gamma _{\ddot{\nu }}^{-1}$ is a stellar damping time-scale, and Tobs is the total observing time. Here we combine this formula with a hierarchical Bayesian scheme to infer the population-level distribution of npl for a pulsar population of size M. The scheme is validated using synthetic data to quantify its accuracy systematically and prepare for its future application to real, astronomical data. For a plausible test population with M = 100 and injected npl values drawn from a population-level Gaussian with mean μpl = 4 and standard deviation σpl = 0.5, intermediate between electromagnetic braking and mass quadrupole gravitational radiation reaction, the Bayesian scheme infers $\mu _{\rm pl}=3.89^{+0.24}_{-0.23}$ and $\sigma _{\rm pl}=0.43^{+0.21}_{-0.14}$. The M = 100 per-pulsar posteriors for npl and $\sigma ^{2}_{\ddot{\nu }}\gamma _{\ddot{\nu }}^{-2}$ contain 87 % and 69 %, respectively, of the injected values within their 90 % credible intervals. Comparable accuracy is achieved for (i) population sizes spanning the range 50 ≤ M ≤ 300, with fractional errors ranging from 2 % to 6 % for μpl, and 12 % to 54 % for σpl, and (ii) wide priors satisfying μpl ≤ 103 and σpl ≤ 102, which accommodate plausible spin-down mechanisms with $\dot{K}\ne 0$ and $\vert \dot{K} / K \vert \gg \vert \dot{\nu }/\nu \vert$. The Bayesian scheme generalizes readily to other plausible astrophysical situations, such as pulsar populations with bimodal npl distributions.- Book : ()
- Pub. Date : 2025
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2025
Abstract
For designing high-field electromagnets, the Lorentz force on coils needs to be computed in order to design suitable support structures, and the inductance should be computed to evaluate the stored energy and dynamics. Also, the magnetic field and its variation inside the conductor is of interest for computing stress and strain, and due to superconducting quench limits. For these force, inductance, energy, and internal field calculations, the coils cannot be naively approximated as infinitesimally thin filaments due to divergences when the source and evaluation points coincide, so more computationally demanding calculations are usually required, resolving the finite cross-section of the conductors. Here, we present a new alternative method that enables the internal magnetic field vector, self-force, and self-inductance to be computed rapidly and accurately within a 1D filament model. The method is applicable to coils for which the curve center-line can have general noncircular shape, as long as the conductor width is small compared to the radius of curvature. This paper extends a previous calculation for circular-cross-section conductors [Hurwitz et al, IEEE Trans. Magnetics (2024)] to consider the case of rectangular cross-section. The reduced model is derived by rigorous analysis of the singularity, regularizing the filament integrals such that they match the true high-dimensional integrals at high coil aspect ratio. The new filament model exactly recovers analytic results for a circular coil, and is shown to accurately reproduce full finite-cross-section calculations for a non-planar coil of a stellarator magnetic fusion device. Due to the efficiency of the model here, it is well suited for use inside design optimization.- Book : ()
- Pub. Date : 2025
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