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2025
A major advance in rectal cancer was the evidence supporting short-course radiotherapy and long-course chemoradiotherapy. Both have been shown to improve local outcomes. Total neoadjuvant therapy (TNT) is the new kid on the block that provides further benefit of improving local responses as well as reducing systemic relapses, thus increasing overall survival. Details of the four key TNT trials are discussed. They pave the way for nonoperative management for patients who achieve clinical complete responses.- Book : ()
- Pub. Date : 2025
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2025
We study potential contribution of the heavy right-handed neutrino exchange in the process e+e−→W+W−. This process is sensitive to heavy neutrinos with masses larger than s. The Monte Carlo simulation of the studied process is performed assuming the seesaw type-I model, where heavy right-handed neutrinos (heavy neutral leptons, HNLs) are introduced in the leptonic sector. Within the Standard Model (SM), the process has a large cross section described by diagrams with s-channel Z/γ exchange and t-channel active neutrino exchange. Respectively, the t-channel right-handed neutrino exchange amplitude will interfere with these SM amplitudes. However, the angular distributions of the W boson production and decay are different for the right-handed neutrino and SM amplitudes. That can be used to evaluate potential HNL contribution using the extended likelihood method. The simulation of the e+e−→W+W− process is performed at the 1 TeV center-of-mass energy and polarization Pe+e− of (20%, −80%), which is a standard option for the future linear e+e− International Linear Collider. Both W bosons are reconstructed from two hadronic jets. Simulation of the SM background processes is also done. The beam-induced backgrounds and the initial state radiation effects are taken into account. The majority of background processes are effectively suppressed by the cuts on the invariant masses of two and four jets. Finally, we obtain upper limits on the mixing parameter |VeN|2 as a function of M(N).
Published by the American Physical Society
2025
- Book : 111(1)
- Pub. Date : 2025
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2025
- Book : ()
- Pub. Date : 2025
- Page : pp.170240-170240
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2025
Abstract
Environmental variation has long been considered a key driver of evolutionary change, predicted to shape different strategies, such as genetic specialization, plasticity, or bet-hedging to maintain fitness. However, little evidence is available with regards to how the periodicity of stressors may impact fitness across generations. To address this gap, I conducted a reciprocal split-brood experiment using the freshwater crustacean, Daphnia magna, and an ecologically relevant environmental stressor, ultraviolet radiation (UVR). I exposed one group to constant and another group to fluctuating UVR conditions. Despite receiving the same dose of UVR, the first experimental generation displayed significant treatment-by-genotype interactions with respect to survival and reproductive output, as well as a delayed reproductive maturity under fluctuating UVR conditions. In the following experimental generation individuals exposed to fluctuating UVR exhibited higher fitness than those in a constant UVR regime. The ancestral conditions, i.e., maternal environment, however affected the survival probability and reproductive output, but did not significantly influence the maturation date. Overall, I demonstrate that the delivery of a stressor, not just its intensity, can have profound fitness consequences across generations, with important implications for seasonal succession of genotype–phenotype patterns in natural environments.- Book : 15(1)
- Pub. Date : 2025
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2025
- Book : ()
- Pub. Date : 2025
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2025
Abstract
Maximizing the discovery potential of increasingly precise neutrino experiments will require an improved theoretical understanding of neutrino-nucleus cross sections over a wide range of energies. Low-energy interactions are needed to reconstruct the energies of astrophysical neutrinos from supernovae bursts and search for new physics using increasingly precise measurement of coherent elastic neutrino scattering. Higher-energy interactions involve a variety of reaction mechanisms including quasi-elastic scattering, resonance production, and deep inelastic scattering that must all be included to reliably predict cross sections for energies relevant to DUNE and other accelerator neutrino experiments. Refined nuclear interaction models in these energy regimes will also be valuable for other applications, such as measurements of reactor, solar, and atmospheric neutrinos. This manuscript discusses the theoretical status, challenges, required resources, and path forward for achieving precise predictions of neutrino-nucleus scattering and emphasizes the need for a coordinated theoretical effort involved lattice QCD, nuclear effective theories, phenomenological models of the transition region, and event generators.- Book : ()
- Pub. Date : 2025
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2025
Abstract. Quantifying environmental radiation dose rates is an essential step in age calculation using trapped charge dating methods. A means of rapid dose rate estimation would therefore be useful for a variety of reasons, especially in contexts where rapid equivalent dose estimates are available. For instance, for informing sampling strategy, providing initial age estimates, or supporting portable luminescence studies. However, high-precision methods often used for calculating dose rates are typically time consuming and expensive and are impractical for such ‘range-finder’ applications. Portable X-ray fluorescence (pXRF) offers a rapid means of measuring the Potassium (K) concentration of sediment, although the other radionuclides typically used to calculate dose rates (Uranium (U) and Thorium (Th)) fall beneath its detection limits at the quantities at which they are usually present in sediments. In this study, we investigate whether pXRF measurements of K concentration alone can be used to accurately estimate total environmental dose rates. A large, global training dataset of 1473 radionuclide samples is used to generate a set of linear relationships between (1) K concentration and external beta dose rate; (2) external beta and gamma dose rates; and (3) external gamma and alpha dose rates. We test the utility of these relationships by measuring the K contents of 67 sediment samples with independent high-precision radionuclide data from a variety of contexts using pXRF. The resulting K concentrations are then converted to external dose rate estimates using the training equations. A simplified set of attenuation parameters are used to correct infinite matrix dose rate estimates, and these are combined with cosmic ray and internal contributions to rapidly calculate total environmental dose rates for a range of theoretical, common luminescence dating scenarios (such as 180–250 μm quartz that has undergone etching). Results show that pXRF can accurately measure K concentrations in a laboratory setting. The training equations can predict external beta dose rates accurately based on K content alone, whilst external alpha dose rates are predicted less accurately. In combination, total estimated dose rates show good agreement with their counterparts calculated from high-precision methods, with 68–98 % of our results lying within ±20 % of unity depending on the scenario. We report better agreement for scenarios where alpha contributions are assumed to be negligible (e.g., in the case of etched, coarse-grained quartz or potassium feldspar). The use of simplified attenuation factors to correct estimated infinite matrix dose rates does not contribute significantly to resulting scatter, with uncertainties mostly resulting from the training equations. This study serves as a proof of concept that pXRF measurements, along with a set of linear equations and a simplified correction procedure, can be used to rapidly calculate range-finder environmental dose rates.
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- Pub. Date : 2025
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2025
Following our previous work on hybrid quantum states in the Russo-Susskind-Thorlacius model, we study its most interesting solution representing a completely regular spacetime with the structure of causal diamond, containing an apparent horizon and radiation at infinity. Adapting recent computations of radiation entropy in terms of the entropy of entanglement, we find that this entropy follows a Page curve. This confirms our previous result [], which was obtained by directly calculating the thermodynamic entropy of radiation at infinity. We also investigate the presence of a possible island in these systems and find that it does not seem to play a role in contributing to the generalized black hole entropy.
Published by the American Physical Society
2025
- Book : 111(2)
- Pub. Date : 2025
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2025
- Book : ()
- Pub. Date : 2025
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2025
Sea fog significantly impacts marine activities, ecosystems, and radiation balance. We analyzed the decadal variation characteristics of sea fog frequency (SFF) over the northwestern Pacific and investigated the roles of the Pacific decadal oscillation (PDO) and sea surface temperature (SST) warming in driving these changes. The results show that SFF experienced a significant and sudden decadal increase around 1978 (up by 12.9%) and a prominent decadal decrease around 1999 (down by 7.8%). The sudden increase in SFF around 1978 was closely related to the PDO. A positive PDO phase induced unusual anticyclonic circulation and southerly winds over the northwestern Pacific, enhancing low-level atmospheric stability and moisture supply, thus facilitating sea fog formation. Nevertheless, the decrease in SFF around 1999 was related to SST warming in the north Pacific. The rise in sea temperatures weakened the SST front south of the foggy region, reducing the cooling and condensation of warm air necessary for sea fog formation. This study enhances the understanding of the decadal variability mechanism of SFF over the northwestern Pacific regulated by large-scale circulation systems and provides a reference for future sea fog forecasting work.- Book : 16(2)
- Pub. Date : 2025
- Page : pp.130-130
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