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2025
Abstract
Near the ends of their lives, supernova remnants (SNRs) enter a “radiative phase,” when efficient cooling of the postshock gas slows expansion. Understanding SNR evolution at this stage is crucial for estimating feedback in galaxies, as SNRs are expected to release energy and momentum into the interstellar medium near the ends of their lives. A standard prediction of SNR evolutionary models is that the onset of the radiative stage precipitates the formation of a dense shell behind the forward shock. In Paper I, we showed that such shell formation yields detectable nonthermal radiation from radio to γ-rays, most notably emission brightening by nearly 2 orders of magnitude. However, there remains no observational evidence for such brightening, suggesting that this standard prediction needs to be investigated. In this paper, we perform magnetohydrodynamic simulations of SNR evolution through the radiative stage, including cosmic rays (CRs) and magnetic fields to assess their dynamical roles. We find that both sources of nonthermal pressure impede shell formation, reducing shell densities by a factor of a few to more than an order of magnitude. We also use a self-consistent model of particle acceleration to estimate the nonthermal emission from these modified SNRs and demonstrate that, for reasonable CR acceleration efficiencies and magnetic field strengths, the nonthermal signatures of shell formation can all but disappear. We therefore conclude that the absence of observational signatures of shell formation represents strong evidence that nonthermal pressures from CRs and magnetic fields play a critical dynamical role in late-stage SNR evolution.- Book : 980(2)
- Pub. Date : 2025
- Page : pp.167-167
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2025
- Book : 181()
- Pub. Date : 2025
- Page : pp.105619-105619
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2025
ABSTRACTShrew moles (Uropsilus), belonging to subfamily Uropsilinae of family Talpidae, were predominantly found in Myanmar, Vietnam, Bhutan, and Southwestern China. However, the extent distribution range of species within Uropsilus remains unclear. In 2022, we collected 18 specimens of Uropsilus from the western mountains of Henan Province in central China. Based on the mitochondrial (CYT B) and nuclear (RAG1 + RAG2) genes, the phylogenetic relationships, divergence times, and species delimitation of Uropsilus were analyzed. The results showed that the genetic distance of CYT B between new species and other species of Uropsilus ranged from 8.44% to 18.23%; the new species was a distinct valid species and speciated in the early Pleistocene (2.16 Ma, 95% CI = 2.00–2.65) based on phylogenetic analyses. Morphologically, the new species was distinguishable from the other species of Uropsilus by its yellowish–brown dorsum and ash‐black venter, short tail, slender and curved zygomatic arch, upper inward‐curved I1, and lack of a gap between I1 and I2. The combined results of morphological and molecular phylogenetic analysis indicated that the samples from Henan Province represented a new species—Uropsilus funiushanensis sp. nov. The specimens collected from the mountainous area of western Henan Province and Shennongjia in Hubei Province were identified as the same species. We suggested the evolutionary mechanism of the dental formula of U. funiushanensis and U. soricilus groups should be explored in the future.- Book : 15(2)
- Pub. Date : 2025
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2025
Abstract
A recent experiment showed that a Cherenkov radiation
spectrum from thin radiators with a wavelength-dependent refractive
index could transform into quasi-monochromatic spectral
lines. Simulations based on the standard Geant4 toolkit could not
correctly describe the experimental results because Geant4 uses the
traditional Frank-Tamm theory developed for an ideal (infinitely
thick) radiator. Because of that, we endeavor to present a new way
of utilizing Cherenkov radiation using newly developed Geant4 models
and comparing simulation results with the experimental ones. Now,
one can analyze quasi-monochromatic Cherenkov spectral lines using
Geant4, which is a significant milestone for investigating the
possibilities of this technique. Also, this paper should be used as
a text to help people understand the Cherenkov process in Geant4 and
what one can expect from various models.- Book : 20(02)
- Pub. Date : 2025
- Page : pp.P02008-P02008
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2025
The density dependence of nuclear symmetry energy Esym(ρ) remains the most uncertain aspect of the equation of state (EOS) of supradense neutron-rich nucleonic matter. Utilizing an isospin-dependent parameterization of the nuclear EOS, we investigate the implications of the observational crustal fraction of the neutron star (NS) moment of inertia ΔI/I for the Esym(ρ). We find that symmetry energy parameters significantly influence the ΔI/I, while the EOS of symmetric nuclear matter has a negligible effect. In particular, an increase in the slope L and skewness Jsym of symmetry energy results in a larger ΔI/I, whereas an increase in the curvature Ksym leads to a reduction in ΔI/I. Moreover, the ΔI/I is shown to have the potential for setting a lower limit of symmetry energy at densities exceeding 3ρ0, particularly when L is constrained to values less than 60 MeV, thereby enhancing our understanding of supradense NS matter.- Book : 8(1)
- Pub. Date : 2025
- Page : pp.12-12
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2025
Abstract
Background
Treacher Collins syndrome (TCS, MIM #154500), a severe congenital disorder, predominantly involves dysplasia of craniofacial bones and is characterized by features such as downslanting palpebral fissures, lower eyelid colobomas, microtia, and other craniofacial anomalies. Despite its clinical importance, the underlying pathogenic mutations in TCS remain largely uncharacterized, representing a critical knowledge gap for researchers in the field.
Results
To address this, we performed mutation screening on a familial TCS case (trio) and 11 sporadic cases from a Chinese population. We identified 11 mutations predominantly localized to the central repeat domain (CRD) and the C-terminal domain (CTD, including the nuclear localization sequence) of TCOF1. The de novo frameshift mutation identified in the trio led to TCOF1 truncation, disrupting the central repeat domain crucial for binding transcriptional factors. Immunoprecipitation assays revealed that this pathogenic mutation attenuates the interaction between TCOF1 and transcription-related proteins, such as Pol II. Furthermore, cellular luciferase assays demonstrated that the mutation compromises the nuclear localization capability of TCOF1.
Conclusions
Our findings establish TCOF1 as the primary pathogenic gene in this Chinese TCS cohort, with mutations predominantly in the CRD and CTD, thereby expanding the known mutation spectrum of TCS and informing its prevention strategies.
- Book : 20(1)
- Pub. Date : 2025
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2025
A novel polarization conversion radome based on dielectric-embedded metamaterial elements is proposed to decrease the size of antenna profiles. This radome is composed of two kinds of interlaced dielectric-embedded metamaterial elements to realize the polarization conversion and beam deflection. The structures and characteristics of two types of dielectric-embedded metamaterial elements have been studied and analyzed. By selecting an appropriate dielectric material and applying periodic boundary conditions to optimize these two kinds of dielectric-embedded metamaterial elements, the radome made up of these metamaterial elements eventually is mounted atop a square horn antenna. Simulation results indicate that the antenna radome enables the horn antenna to achieve polarization conversion and beam deflection at the operating frequency. The maximum beam deflection angle can be 29° within a gain reduction of 1 dB, while the axial ratio remains below 1.5 dB and the reflection coefficient continuously remains below −22 dB. Moreover, the power-handling capacity of each metamaterial element within the radome is above 60 kW.- Book : 15(2)
- Pub. Date : 2025
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2025
- Book : 37(2)
- Pub. Date : 2025
- Page : pp.497-497
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2025
Traditional antitumor methods of special treatment for malignant neoplasms are open surgery, chemo- and radiation therapy, and, in recent years, immunotherapy. At the same time, they are associated with a number of unfavorable factors (primarily during the surgical stage of special treatment), such as long periods of patients’ hospital stay and subsequent recovery. One of the main goals of technological and medical research in the field of combating malignant neoplasms is to significantly reduce local, regional and systemic side effects compared with traditional methods of treatment and provide additional therapeutic opportunities in cases where traditional methods are ineffective. Not so long ago, relatively new methods of antitumor treatment have been introduced into clinical practice, such as radiofrequency, laser, microwave and cryoablation, and high-intensity focused ultrasound (HIFU), which is currently being intensively improved as a non-invasive method of treating a number of primary as well as recurrent solid tumors and metastatic diseases. The article presents in a quite brief form the stages of HIFU method formation, methodological aspects and physical foundations of HIFU therapy, as well as very positive results already achieved in clinical application of this method for the treatment of malignant tumors.- Book : 105(4)
- Pub. Date : 2025
- Page : pp.224-231
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2025
- Book : ()
- Pub. Date : 2025
- Page :
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