bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of blue core discharge characteristics in a nonhomogeneous helicon plasma coupled by Nagoya III antenna and double-saddle antenna
Authors: Sun Meng , Yin Xianyi , Zhang Haibao
Published: January 2025

Coupled antennas are critical for the discharge characteristics of high-density helicon plasma. This paper compared the coupling effects of Nagoya III antenna and double-saddle antenna on the blue core discharge characteristics in a nonhomogeneous helicon plasma. Langmuir probe, Nikon D90 camera, intensified charge-coupled device camera, and optical emission spectrometer were used to characterize the plasma mode transition, discharge image, spatial distribution of plasma density, and electron temperature. The results showed that the Nagoya III antenna was more likely to excite the helicon plasma discharge. It can enter W mode discharge at 200 W and appear blue core phenomenon at about 500 W with a higher plasma density. The axis distribution of spectral line intensity indicated that Nagoya III antenna has a stronger coupling ionization effect. The radial distributions of the plasma density and electron temperature demonstrated the stronger electron-neutral collision frequency under the excitation of Nagoya III antenna. It can be contributed to the higher antenna coupling efficiency, which was calculated to around 93% for Nagoya III antenna after 300 W.
Temporal uniaxial crystal in a dispersion-modulated lattice model
Authors: Jin Meng-Cheng , Chen Ze-Guo , Lu Ming-Hui , Zhan Peng , Chen Yan-Feng
Published: January 2025

Time reflection and refraction, as temporal analogs to spatial phenomena, provide a degree of freedom for manipulating wave dynamics within the temporal domain. In this study, we investigate the dynamics of Gaussian wave packets at time interfaces within one-dimensional lattice models, providing insights into generalized temporal refraction and dispersion control. By redefining time reflection as temporal negative refraction, we propose a generalized temporal Snell's law based on the equivalent refractive index, which effectively predicts both temporal positive and negative refraction. Furthermore, we introduce a “temporal uniaxial crystal” by extending our investigation to a three-band model without symmetry constraints, characterized by double temporal positive and negative refraction. Our approach not only deepens the understanding of time refraction but also offers a versatile tool for studying complex wave behaviors in time-variant systems.
Using pretrained graph neural networks with token mixers as geometric featurizers for conformational dynamics
Authors: Pengmei Zihan , Lorpaiboon Chatipat , Guo Spencer C. , Weare Jonathan , Dinner Aaron R.
Published: January 2025

Identifying informative low-dimensional features that characterize dynamics in molecular simulations remains a challenge, often requiring extensive manual tuning and system-specific knowledge. Here, we introduce geom2vec, in which pretrained graph neural networks (GNNs) are used as universal geometric featurizers. By pretraining equivariant GNNs on a large dataset of molecular conformations with a self-supervised denoising objective, we obtain transferable structural representations that are useful for learning conformational dynamics without further fine-tuning. We show how the learned GNN representations can capture interpretable relationships between structural units (tokens) by combining them with expressive token mixers. Importantly, decoupling training the GNNs from training for downstream tasks enables analysis of larger molecular graphs (that can represent small proteins at all-atom resolution) with limited computational resources. In these ways, geom2vec eliminates the need for manual feature selection and increases the robustness of simulation analyses.
Wavelength-insensitive and fast photothermoelectric response in magnetic-Weyl-semimetal Co3Sn2S2 crystals
Authors: Jiang Hong-Tao , Yin Cheng-Hao , Cao Lin , Wen Qi-Xun , Sun Su-Tao , Zhou Jian , Yao Shu-Hua , Lv Yang-Yang , Chen Y. B. , Chen Yan-Feng
Published: January 2025

We systematically characterize the photothermoelectric (PTE) effect of pristine and Se-doped (4%, 8%, and 11%) Co3Sn2S2 crystals, a magnetic-Weyl-semimetal, on electromagnetic-wave wavelength and temperature. The photovoltages of these Co3Sn2S2 crystals are insensitive to the electromagnetic-wave wavelength, with 23% variance, in bands ranging from 444 to 1550 nm. Remarkably, the 4%-Se doped Co3Sn2S2 demonstrates the best PTE performance among these samples, yielding a 22.4 mV/W optical responsivity and a short response time (∼100 ms) under 1550 nm illumination. The photovoltage of Co3Sn2S2 nearly monotonically increased with increasing temperature. The theoretical analyses verify that the wavelength-insensitive PTE response of Co3Sn2S2 comes from the nearly same trend of its wavelength-dependent optical refractive index and extinction coefficient, and the best PTE performance of 4%-Se doped Co3Sn2S2 is attributed to the largest product of Seebeck coefficient and electrical conductivity. This work demonstrates that magnetic Weyl semimetals may be promising for infrared photodetection.
Interstellar spectroscopic detection of HC(S)NC and DC(S)NC
Authors: Trabelsi Tarek , El-Tohamy Maha F. , Mostafa Gamal A. E. , Francisco Joseph S.
Published: January 2025

The detection of HC(S)CN in TMC-1 suggests that HC(S)NC may also exist. To aid in its possible detection, HC(S)NC and its deuterated isotopologue DC(S)NC were investigated via high-level ab initio methods, specifically CCSD(T) and CCSD(T)-F12. By utilizing multidimensional potential energy surfaces derived from explicitly correlated coupled-cluster calculations, we analyzed their geometrical parameters, vibrational frequencies, rotational constants, and a comprehensive set of spectroscopic constants generated via the vibrational second-order perturbation theory, vibrational self-consistent field, and vibrational configuration interaction theory(VCI) approaches. HC(S)NC is thermodynamically stable relative to the HCS + NC dissociation limit, with a predicted bond dissociation energy of 4.1 eV. The calculated vibrational frequencies are characterized by two bright modes that correspond to CN stretching. Finally, HC(S)NC shows a significant dipole moment, predicted to be 1.9 D, making its detection via rotational spectroscopy plausible.
Toward model-free temperature diagnostics of warm dense matter from multiple scattering angles
Authors: Bellenbaum H. M. , Bachmann B. , Kraus D. , Gawne Th. , Böhme M. P. , Döppner T. , Fletcher L. B. , MacDonald M. J. , Moldabekov Zh. A. , Preston T. R. , Vorberger J. , Dornheim T.
Published: January 2025

Warm dense matter plays an important role in astrophysical objects and technological applications, but the rigorous diagnostics of corresponding experiments is notoriously difficult. In this work, we present a model-free analysis of x-ray Thomson scattering (XRTS) measurements on isochorically heated graphite obtained at the Linac Coherent Light Source at multiple scattering angles. We demonstrate that the recent imaginary-time thermometry technique works for scattering data that have been measured in both forward and backward scattering geometry. This opens up the way toward a rigorous quantification of nonequilibrium effects in future experiments, where XRTS measurements are being obtained from multiple scattering angles from the same sample.
Dead-zone-free single-beam atomic magnetometer based on free-induction-decay of Rb atoms
Authors: Mehta Shrey , Samanta G. K. , Grewal Raghwinder Singh
Published: January 2025

Free-induction-decay (FID) magnetometers have evolved as simple magnetic sensors for sensitive detection of unknown magnetic fields. However, these magnetometers suffer from a fundamental problem known as a “dead zone,” making them insensitive to certain magnetic field directions. Here, we demonstrate a simple experimental scheme for the dead-zone-free operation of a FID atomic magnetometer. Using a single laser beam containing equal strength of linear- and circular-polarization components and amplitude modulation at a low-duty cycle, we have synchronously pumped the rubidium (87Rb) atoms with both first- and second-order frequency harmonics. Such a pumping scheme has enabled us to observe the free Larmor precession of atomic spins at a frequency of ΩL (orientation) and/or 2ΩL (alignment) in a single FID signal, depending on the direction of the external magnetic field. We observed that the amplitude of the FID signal does not go to zero for any magnetic field direction, proving the absence of dead zones in the magnetometer. The magnetometer has a sensitivity in the range of 3.2–8.4 pT/Hz in all directions. Our experimental scheme can be crucial in developing miniaturized atomic magnetometers for various practical applications, including geomagnetic applications.
Piezo-viscous flows of couple stress fluids in squeeze film in an annular circular discs
Authors: Velisoju Swathi , Murthy J. V. Ramana
Published: January 2025

Experimental evidence shows that for certain fluids, at high pressures, the viscosity of the fluid depends on pressure. Such fluids are referred to as piezo-viscous fluids. The present paper investigates the piezo-viscous dependence of coupled stress fluid flow between parallel annular disks. The study assumes an exponential change in viscosity with pressure and analytically approximates the pressure using a perturbation method, with the viscosity parameter as a small perturbation parameter. The results, which include the calculation and visual demonstration of squeeze film time, load-bearing capacity, and pressure over various viscosity-pressure characteristics, reveal a significant relationship between the increase in piezo-viscosity and the growth in pressure, response time, and bearing load. These findings have direct implications for practical applications in bearings, seals, and lubrication, where the control of viscosity and pressure is crucial for maintaining smooth operation and enhancing productivity.
Low-temperature buffer layer-assisted heteroepitaxial growth of γ-CuI thin films by pulsed laser deposition: Tailoring electrical properties
Authors: Chen Yang , Bar Michael S. , Selle Susanne , Splith Daniel , Lorenz Michael , Grundmann Marius , von Wenckstern Holger
Published: January 2025

As the first discovered p-type transparent conductive material, copper(I) iodide (CuI) is considered the most competitive p-type candidate in the field of transparent electronics. Herein, we introduced a low-temperature buffer-layer-assisted strategy to grow γ-CuI with significantly improved structural quality and electrical transport properties by pulsed laser deposition. By adjusting the growth temperature, we can manipulate the rotation domain structure, control the hole concentration Nh from 1014 to 1019 cm−3, and achieve mobility μh = 25 cm2 V−1 s−1 being similar to that of bulk CuI. Based on the temperature-dependent Hall-effect measurement, the ionization energy of a shallow acceptor of EI,S = 137 ± 8 meV and that of a deeper acceptor of EI,D = 262 ± 23 meV were determined. This grown strategy not only enables high-quality CuI film preparation, but also to tailor their electrical properties for integration with n-type semiconductors in transparent electronic circuits.
Quantitative analysis of leakage current in III-nitride micro-light-emitting diodes
Authors: Wong Matthew S. , Tak Tanay , Ni Andrea Y. , Nitta Kent , Gandrothula Srinivas , Kim JaeKwon , Cha NamGoo , Mishra Umesh K. , Speck James S. , DenBaars Steven P.
Published: January 2025

The electrical characteristics under forward- and reverse-bias conditions of III-nitride blue and green micro-light-emitting diodes (μLEDs) are analyzed. A fitting model is proposed to determine the contributions of reverse leakage current and the effectiveness of sidewall treatments. Moreover, the forward-bias currents of the μLEDs are examined using the extracted ideality factor to examine the impacts of sidewall defects. The results show that sidewall treatments are highly effective for suppression of leakage currents. From the efficiency perspective, higher wall-plug efficiency (WPE) than external quantum efficiency (EQE) is observed when the operating voltage is lower than the photon voltage in both blue and green 20 × 20 μm2 devices. This enhancement of the WPE over the EQE is due to the suppression of Shockley–Read–Hall (SRH) nonradiative recombination. These observations indicate that μLEDs with sidewall treatments not only improve optical performance but also further enhance the electrical performance of devices by suppressing the leakage current paths due to SRH nonradiative recombination processes.
Electrochemical reduction for modulating spin state of nickel: A pathway to improved water and seawater oxidation
Authors: Shuai Yu , Liu Shucheng , Zhang Tao , Liu Yi
Published: January 2025

Understanding the electronic structure of catalysts is crucial for analyzing electrocatalyst behavior. Here, we present a straightforward method to modify the electronic configuration of active sites in nickel-iron-niobium layered double hydroxides (NiFeNb-LDHs) via electrochemical reduction (ER), uncovering key factors that enhance oxygen evolution reaction (OER) activity. The results indicate that ER-NiFeNb-LDHs display excellent OER performance and long-term stability over 60 h in various electrolytes (271.99 mV@50 mA cm−2 in 1M KOH and 280.56 mV@50 mA cm−2 in 1M KOH +0.5M NaCl). Furthermore, the cell voltage of the two-electrode electrolyzer ER-NiFeNb-LDHs ǁ Pt/C achieves a current density of 50 mA cm−2 at an ultra-low voltage of 1.58 V, significantly outperforming the commercial RuO2ǁPt/C. X-ray absorption spectroscopy, magnetic characterization, and density functional theory calculations reveal that the unsaturated coordination environment created by ER modifies the electronic state distribution between eg and t2g orbitals, effectively lowering the spin state of nickel and enhancing its OER activity.
Nanopore evaporation prediction model with a complete explanation of the equivalent evaporation coefficient
Authors: Zhao Pengsheng , Xia Guodong , Li Ran
Published: January 2025

Evaporation from nanoporous membranes is an emerging and efficient thermal management strategy for microelectronic devices, and its mechanism has been extensively studied. It has been found that there are many factors that affect the evaporation rate, such as porosity and meniscus. In this paper, the equivalent evaporation coefficient is introduced to account for all these factors to transform the nanopore evaporation into one-dimensional plane evaporation so that the evaporation flux from any nanopore configuration can be simply solved. Theoretical analysis and modeling are performed, and direct simulation Monte Carlo (DSMC) method is used to verify the reliability of the model. The proposed equivalent evaporation coefficient incorporates the meniscus shape, nanopore transmissivity, nanopore porosity, and the intrinsic evaporation coefficient with solid physical sounds. The overall accuracy of our model is excellent, with 94.5% of simulated data being predicted within 5%. The physical meaning of the equivalent evaporation coefficient presented in this paper is clear and comprehensive, which significantly facilitates engineering application.
Highly deformable flapping membrane wings suppress the leading edge vortex in hover to perform better
Authors: Gehrke Alexander , Mulleners Karen
Published: January 2025

Airborne insects generate a leading edge vortex when they flap their wings. This coherent vortex is a low-pressure region that enhances the lift of flapping wings compared to fixed wings. Insect wings are thin membranes strengthened by a system of veins that does not allow large wing deformations. Bat wings are thin compliant skin membranes stretched between their limbs, hand, and body that show larger deformations during flapping wing flight. This study examines the role of the leading edge vortex on highly deformable membrane wings that passively change shape under fluid dynamic loading maintaining a positive camber throughout the hover cycle. Our experiments reveal that unsteady wing deformations suppress the formation of a coherent leading edge vortex as flexibility increases. At lift and energy optimal aeroelastic conditions, there is no more leading edge vortex. Instead, vorticity accumulates in a bound shear layer covering the wing’s upper surface from the leading to the trailing edge. Despite the absence of a leading edge vortex, the optimal deformable membrane wings demonstrate enhanced lift and energy efficiency compared to their rigid counterparts. It is possible that small bats rely on this mechanism for efficient hovering. We relate the force production on the wings with their deformation through scaling analyses. Additionally, we identify the geometric angles at the leading and trailing edges as observable indicators of the flow state and use them to map out the transitions of the flow topology and their aerodynamic performance for a wide range of aeroelastic conditions.
Majority and minority language elementary school children with and without reading difficulties in a regular foreign
language and an immersion program
Authors: Steinlen Anja , Piske Thorsten
Published: January 2025

In Germany, the number of bilingual elementary schools, in which subjects are taught in a foreign language (FL),
is on the rise. While previous research highlights advantages for typically developing students in such programs, little is known
about at-risk learners, including those with reading difficulties (RD), affecting 5–10% of all German school children. This
exploratory study investigates FL English abilities in 359 Year 4 elementary school students by comparing minority (L2) and
majority language (L1) students with and without RD in a partial immersion (IM) and a regular (EFL) program. Students with RD
(n = 95) were identified through a standardized German reading test and cognitive tests. Results showed no
impact of language background on English tests, but teaching program was identified as a significant predictor, with IM students
outperforming EFL peers, irrespective of RD. These preliminary findings indicate that students with RD may benefit from IM
programs, possibly due to increased literacy activities.
The semantic change of faqare (‘vertebra’, ‘unit’)
as a numeral classifier in Persian
Authors: Soltani Reza , Janda Laura A.
Published: January 2025

This article deals with an ongoing semantic change in which
Persian faqare (‘vertebra’, or ‘unit’) is transitioning from a
specific numeral classifier to a general numeral classifier in the grammatical
construction Num + faqare + NP. In this transition the
connections to the prototypical meanings of faqare are being
weakened. This marks a late phase in the life cycle of a radial category, when
the category is eroding, leading to productivity in the range of fillers for the
NP slot. This late phase of radial categories has received little attention in
the scholarly literature. We cite corpus data showing that a variety of factors
contribute to the productive extension of faqare, including:
context; the presence of prototypical collocates with faqare
adjacent to the construction; and register, where mismatches produce humorous
effects.
Bridging gaps and leveraging opportunities for One Health: Feedback from the 8th World One Health Congress
Authors: Caron Alexandre , Garine-Wichatitsky Michel de , Figuié Muriel , Meunier Julie , Mugabe Prisca , Zinsstag Jakob
Published: January 2025

We attended the 8th WOHC between the 20th and 23rd of September 2024 in Cape Town, South Africa and we provide here our feedback with a specific perspective on the policy implications. The One Health approach still needs to go beyond diseases and to embrace a truly holistic definition of health in both its pathogenic and salutogenic components. This broader definition of health should be applied to all human groups with more equity and inclusivity, to non-human animals, as sentient beings, and to ecosystems and the environment in a more integrated way.

One Health impact statement

Given our multidisciplinary expertise and varied interests, we hope to have grasped the quintessence of the 8th World One Health congress in Cape Town in September 2024 and may therefore be able to provide a fair impression, albeit necessarily biased and personal. Our reflections below will be guided by the One Health High Level Expert Panel (OHHLEP) foundational principles of the new One Health definition (Mettenleiter
et al
.,
2023
).
CRISPR/Cas genome editing: Innovations and impacts on animal protein production
Authors: Rocha Maximiano Mariana , Franco Octávio Luiz
Published: January 2025

Food security has become an urgent global challenge as global population growth and climate change intensify. Livestock production systems must adapt to meet the growing demand for high-quality animal protein while minimizing environmental impacts. CRISPR/Cas genome editing has emerged as a transformative technology, enabling precise genetic modifications that enhance productivity, improve disease resistance, and promote animal welfare. In this context, this review aims to provide a comprehensive analysis of the current advancements in CRISPR/Cas genome editing tools for animal protein production, while addressing the challenges and future prospects of applying genome editing in livestock farming. Several studies have targeted genes associated with meat production, milk improvement, disease susceptibility, and animal welfare. The results have shown success in developing edited animals that increase meat production and milk quality and make animals more resilient to various infections, thereby reducing the economic losses associated with disease outbreaks. However, this advance still faces challenges, including technical, regulatory and ethical issues, and public acceptance. Even so, some of these edited animals are in the advanced stages of the regulatory approval process in some countries, including cattle with heat tolerance, pigs with resistance against PRRS-virus, and some fish that present an increase in meat production. In this context, this review consolidates current knowledge on CRISPR/Cas applications in animal protein production, highlights significant achievements, and addresses challenges related to the regulatory landscape, public perception, and ethical concerns. Furthermore, it emphasizes the importance of adaptable regulatory frameworks to ensure the responsible and sustainable advancement of genome editing in livestock.
A sensing material-free and simple readout MEMS sensor for detecting helium
Authors: Mohaidat Sulaiman , Okour Mohammad , Alsaleem Fadi
Published: January 2025

In this work, we report a method that enables a standard electrostatic microelectromechanical system (MEMS) device to perform complex sensing functionalities, such as detecting the presence of helium without a sensing material or a conditioning circuit. Helium is a noble, odorless, non-reactive gas that is very challenging to detect. It is used in critical applications such as storing nuclear fuel waste inside a dry cask. In these applications, its leakage from the dry cask may indicate the cask’s safe operation’s degradation. A departure from the common practice of exciting the MEMS around its mechanical resonance, the method is based on exciting the MEMS around its electrical resonance circuit. This method shows that the tiny difference between the air dielectric constant (1.000 59) and helium (1.000 067) corresponding to only a few Femtofarad level capacitances produces a 25 mV difference without a conditioning circuit. Simulation results confirmed those findings and explored the sensor response at different operation conditions. This method eliminates the need for a heated microstructure and the need for absorption material. This method is not limited to gas sensing. It can be applied to other sensing mechanisms, such as acceleration and pressure measurements, and eliminate the complex circuit to read small capacitance in these applications.
Focal beam position and shape manipulation enabled by polarization and plasmonic metasurfaces
Authors: Chang Chin-Kai , Lee Da
Published: January 2025

Over the past few years, plasmonic metasurfaces (PMs) have shown significant potential for the manipulation of the focal beam shape and position. However, traditional hole-type PMs have lower optical transmission (<5%) and lack design freedom because most areas are opaque. Herein, we propose an island-type PM design that achieves high optical transmission (approximately 50%), while allowing the focal position to be controlled via incident polarization. This PM exhibits the geometric phase characteristics of anisotropic nano-ellipses, and an additional phase shift is induced by varying the nano-ellipse rotation angles. The metasurface can achieve phase modulation via a spatial nano-ellipse arrangement and enables focus at the desired location under specific incident polarization handedness. Moreover, the number of radial multiplexing in this PM can be increased to provide multiple focal points to endow the metasurface with an extended focal depth (12.2 times the incident wavelength). The PM performance was demonstrated through simulations and experiments. The proposed metasurface has a highly versatile design and has significant and diverse applications across multiple optical fields.
A simple plan strategy to optimize the biological effective dose delivered in robotic radiosurgery of vestibular schwannomas
Authors: Moutsatsos A , Pantelis E
Published: January 2025

Using the concept of biologically effective dose (BED), the effect of sublethal DNA damage repair (SLR) on the bio-efficacy of prolonged radiotherapy treatments can be quantified (BEDSLR). Such treatments, lasting more than 20 min, are typically encountered in stereotactic radiosurgery (SRS) applications using the CyberKnife (CK) and Gamma knife systems. Evaluating the plan data from 45 Vestibular Schwannoma (VS) cases treated with single fraction CK-SRS, this work demonstrates a statistically significant correlation between the marginal BEDSLR delivered to the target (m-BEDSLR) and the ratio of the mean collimator size weighted by the fraction of total beams delivered with each collimator (

w
m

Cs

), to the tumor volume (Tv). The correlation between m-BEDSLR and

w
m

Cs

Tv

datasets was mathematically expressed by the power function

m
−

BE

D

SLR

=
85.21

 

(

±
1.7
%

)

⋅

(

w
m

C
s

T
v

)

(

0.05
±
7
%

)

 

enabling continuous m-BEDSLR predictions. Using this formula, a specific range of m-BEDSLR levels can a priori be targeted during treatment planning through proper selection of collimator size(s) for a given tumor volume. Inversely, for a selected set of collimators, the optimization range of m-BEDSLR can be determined assuming that all beams are delivered with the smallest and largest collimator size. For single collimator cases or when the relative usage of each collimator size is known or estimated, a specific m-BEDSLR level can be predicted within 3% uncertainty. The proposed equation is valid for the fixed CK collimators and a physical dose prescription (D
pr) of 13 Gy. For alternate D
pr in the range of 11–14 Gy, a linear relationship was found between relative changes of m-BEDSLR(D
pr) and D
pr with respect to m-BEDSLR(13 Gy) and 13 Gy, respectively. The proposed methodology is simple and easy to implement in the clinical setting allowing for optimization of the treatment’s bio-effectiveness, in terms of the delivered BED, during treatment planning.
PhysioEx: a new Python library for explainable sleep staging through deep learning
Authors: Gagliardi Guido , Luca Alfeo Antonio , Cimino Mario G C A , Valenza Gaetano , De Vos Maarten
Published: January 2025

Objective. Sleep staging is a crucial task in clinical and research contexts for diagnosing and understanding sleep disorders. This work introduces PhysioEx (Physiological Signal Explainer), a Python library designed to support the analysis of sleep stages using deep learning (DL) and Explainable AI (XAI). Approach. PhysioEx provides an extensible and modular API for standardizing and automating the sleep staging pipeline, covering data preprocessing, model training, testing, fine-tuning, and explainability. It supports both low-resource devices and high-performance computing clusters and includes pretrained models based on the Sleep Heart Health Study dataset. These models support single-channel EEG and multichannel EEG-EOG-EMG configurations and are easily adaptable to custom datasets. PhysioEx also features a command-line interface toolbox allowing users to streamline the model development and deployment. The library offers a range of XAI post-hoc methods to explain model decisions and align them with expert knowledge. Main results. PhysioEx benchmark state-of-the-art sleep staging models in a standard pipeline. Enabling a fair comparison between them both on the training source and out-of-domain sources. Its XAI techniques provide insights into DL-based sleep staging by linking model decisions to human-understandable concepts, such as American Academy of Sleep Medicine-defined rules. Significance. PhysioEx addresses the need for a standardized and accessible platform for sleep staging analysis, combining DL and XAI. By supporting modular workflows and explainable insights, it bridges the gap between machine learning models and clinical expertise. PhysioEx is publicly available and installable via pip6

6

https://pypi.org/project/physioex/.

, making it a valuable tool for researchers and practitioners in sleep medicine.
Plasma constraints on the millicharged dark matter
Authors: Medvedev Mikhail V. , Loeb Abraham
Published: January 2025

Dark matter particles were suggested to have an electric charge smaller than the
elementary charge unit e. The behavior of such a medium is similar to a collisionless plasma. In
this paper, we set new stringent constraints on the charge and mass of the millicharged dark
matter particle based on observational data on the Bullet X-ray Cluster.
Large field polynomial inflation in Palatini f(R,ϕ) gravity
Authors: Bostan Nilay , Karahan Canan , Sargın Ozan
Published: January 2025

In this paper, we employ the Palatini formalism to investigate the dynamics of large-field inflation using a renormalizable polynomial inflaton potential in the context of f(R,ϕ) gravity. Assuming instant reheating, we make a comparative analysis of large-field polynomial inflation (PI). We first consider the minimal and non-minimal coupling of inflaton in R gravity, and then we continue with the minimally and non-minimally coupled inflaton in f(R,ϕ) gravity. We scan the parameter space for the inflationary predictions (n

s
and r) consistent with the Planck and BICEP/Keck 2018 results as well as the sensitivity forecast of the future CMB-S4 and depict the compliant regions in the ϕ
0-β plane where ϕ
0 and β are two parameters of polynomial inflation model which control the saddle point of the potential and the flatness in the vicinity of this point respectively. We find that a substantial portion of the parameter space aligns with the observational data.
Constraining the history of reheating with the NANOGrav 15-year data
Authors: Maity Suvashis , Bhaumik Nilanjandev , Haque Md Riajul , Maity Debaprasad , Sriramkumar L.
Published: January 2025

Over the last few years, primordial black holes (PBHs) have emerged
as a strong candidate for cold dark matter.
A significant number of PBHs are produced when the strength of the primordial
scalar power spectrum is enhanced on small scales (compared to the COBE
normalized values on large scales).
Such primordial spectra also inevitably lead to strong amplification of the
scalar-induced, secondary gravitational waves (GWs) at higher frequencies.
The recent detection of the stochastic GW background (SGWB)
by the pulsar timing arrays (PTAs) has opened up the possibility of directly
probing the very early universe.
Different studies have shown that, when PBHs are assumed to have been formed
during the epoch of radiation domination, the mechanism for the amplification
of the scalar-induced GWs that is required to explain the PTA data can
overproduce the PBHs over some ranges of masses.
In this work, we assume a specific functional form for the primordial scalar
power spectrum and examine the production of PBHs and the scalar-induced secondary
GWs during the phase of reheating, which precedes the standard epoch of radiation
domination.
Specifically, we account for the uncertainties in the conditions for the
formation of PBHs and ensure that the extent of PBHs produced remains within
the observational bounds.
We find that the scalar-induced SGWB generated during a phase of reheating with
a steeper equation of state (than that of radiation) fit the NANOGrav 15-year
data with a stronger Bayesian evidence than the astrophysical scenario involving
GWs produced by merging supermassive binary black holes.
Study of the muon component in the core-corona model using CONEX 3D
Authors: Botti Ana Martina , Goos Isabel Astrid , Perlin Matias , Pierog Tanguy
Published: January 2025

The discrepancy between models and data regarding the muon content in air showers generated by ultra-high energy cosmic rays still needs to be solved. The CONEX simulation framework provides a flexible tool to assess the impact of different interaction properties and thus address the muon puzzle. In this work, we present the multidimensional extension of CONEX and show its performance compared to CORSIKA by discussing muon-related air-shower features for three experiments: KASCADE, IceTop, and the Pierre Auger Observatory. We also implement an effective version of the core-corona model to demonstrate the impact of the core effect, as observed at the LHC, on the muon content in air showers produced by ultra-high energy cosmic rays. At a primary energy of E
0 = 1019 eV, we obtain an increase of 15% to 20% in the muon content.
Transition behavior between Q-switched mode-locked pulses and noise-like pulses in a thulium doped fiber laser
Authors: Liu Yang , Zhang Peng , Fan Yunlong , Wu Tong , Yu Hao , Tong Shoufeng
Published: January 2025

Noise-like pulses (NLPs) are one of the important phenomena in mode-locked fiber lasers. The formation and evolution of NLPs are important components of nonlinear dynamics. A transition behavior between Q-switched mode-locked (QSML) pulses and NLPs in a figure-9 fiber laser by a nonlinear amplifying loop mirror is firstly reported. At a pump power of 1.817 W, the transition behavior was observed. The shape of the envelope of this transition behavior is similar to that of the shape of the envelope of Q-switched, and the variation of pulse duration with power conforms to the features of QSML. Meanwhile, the autocorrelation curve of the transition behavior partially conforms to the features of NLPs. By increasing the pump power or adjusting the polarization state of the cavity, the transition behavior remains stable. Pure was obtained by additionally adding 50 m single-mode fiber in the cavity. The evolution of transition behavior may facilitate potential contributions to enrich the understanding of the nonlinear dynamics in passively mode-locked lasers.
Analysis of output characteristics of LD end-pumped 2.94 μm continuous-wave Er:YAG laser
Authors: Zhong Yuantian , Zhao Baoyin , Tan Jiahai , Li Dongfang , Dang Bo , Ma Haining , Gao Ming , Lü Hong , Tan Nan
Published: January 2025

Considering self-saturation effect and thermal effect, a detailed theoretical analysis of the output characteristics of the 2.94 μm continuous-wave (CW) Er:YAG laser with a 10 mm long 50 at.% Er:YAG crystal end-pumped by a 976 nm LD is carried out by solving transient rate equations and heat conduction equations. It is shown that there is a minimum pump power threshold of 0.27 W for the 2.94 μm CW Er:YAG laser. The main factor which limits the significant increase of pump power is the thermal damage risk of the crystal’s pump end-face coating. To minimize the risk, the CW operating temperature of the pump end-face coating is set to be no higher than 200 °C, and therefore the value of the pump beam waist radius is limited to 40 μm ⩽ w
0 ⩽ 490 μm. Within the range, a maximum 2.94 μm CW laser output power of 4.03 W is achieved with a pump beam waist radius of 100 μm. By bonding a 2.5 mm long YAG crystal at the pump-end of the Er:YAG crystal, the CW operating temperature of the pump end-face coating is reduced to the room temperature of 20 °C. Under this condition, the limiting factor for a substantial increase of pump power is the thermal damage risk induced by large interior thermal stress of the Er:YAG crystal. Assuming the interior thermal stress of the CW operating Er:YAG crystal is less than 341 MPa according to the material characteristics, the pump power can be increased by increasing the pump beam waist radius. When the beam waist radius is 430 μm, a maximum 2.94 μm CW laser output power of 38.7 W is obtained. Compared with the unbonded condition, the output power level of the 2.94 μm CW Er:YAG laser is promoted.
Access and sustainment of ELMy H-mode operation for ITER pre-fusion power operation plasmas using JINTRAC
Authors: Tholerus E. , Garzotti L. , Parail V. , Baranov Y. , Bonnin X. , Corrigan G. , Eriksson F. , Farina D. , Figini L. , Harting D.M. , Kim S.H. , Koechl F. , Loarte A. , Militello Asp E. , Nordman H. , Pinches S.D. , Polevoi A.R. , Strand P.
Published: January 2025

In the initial stages of ITER operation, ELM mitigation systems need to be commissioned. This requires controlled flat-top operation in type-I ELMy H-mode regimes. Hydrogen or helium plasma discharges are used exclusively in these stages to ensure negligible production of neutrons from fusion reactions. With the expected higher L–H power threshold of hydrogen and helium plasmas compared to corresponding D and D/T plasmas, it is uncertain whether available auxiliary power systems are sufficient to operate in stable type-I ELMy H-mode. This has been investigated using integrated core and edge/SOL/divertor modelling with JINTRAC. Assuming that the L–H power threshold is well captured by the Martin08 scaling law, the presented simulations have found that 30 MW of ECRH power is likely required for the investigated hydrogen plasma scenarios, rather than the originally planned 20 MW in the 2016 Staged Approach ITER Baseline. However, past experiments have shown that a small helium fraction (∼10%) can considerably reduce the hydrogen plasma L–H power threshold. Assuming that these results extrapolate to ITER operation regimes, the 7.5 MA/2.65 T hydrogen plasma scenario is likely to access stable type-I ELMy H-mode operation also at 20 MW of ECRH.
Influence of thermal buoyancy on heat transfer in spacer-filled channels for Membrane Distillation
Authors: Ciofalo M , Cancilla N , Cipollina A , Tamburini A , Micale G
Published: January 2025

Numerical results are discussed for the flow in a horizontal plane channel filled with a novel sphere-rod spacer and exchanging heat from both the top and the bottom sides. Direct Numerical Simulations (DNS) are compared with RANS ones based on different turbulence models in the Reynolds number range 100∼2000. Preliminary comparisons for non-buoyant flow show that models using wall functions perform poorly, grossly overpredicting Nusselt numbers, while ω-based models resolving the viscous-conductive sublayer all yield satisfactory results. In the presence of buoyancy, simulations using either DNS or the k-ω model yield a thermal asymmetry between top and bottom wall, confirmed by experiments and related to the stable or unstable thermal stratification occurring in the lower and upper layers of the channel. The asymmetry, large at low Re, becomes negligible for Re≥1000. The Spalart-Allmaras model yields satisfactory results in the absence of buoyancy but grossly overpredicts Nu in buoyant flows.
Thermal conductivity enhancement in carbon black composite PCM for thermal energy storage
Authors: Mishra Amit Kumar , Ribezzo Alessandro , Morciano Matteo , Bergamasco Luca , Campagnoli Elena , Giaretto Valter , Fasano Matteo , Chiavazzo Eliodoro
Published: January 2025

Phase Change Materials (PCMs) hold significant potential for developing next-generation energy storage technologies due to their cability to reversibly store and release thermal energy with energy density through isothermal phase transition. This work explores improving the heat conduction and thermophysical properties of PCMs, tackling issues such as low thermal conductivity, which can result in longer charge and discharge times. We demonstrated that the thermal conductivity of lauric acid-based PCM (LA-PCM) loaded with carbon black nanoparticles (CBNP) can be significantly enhanced. The PCM loading with 5 wt.% CBNP nanoparticles had an approximately 50% enhancement in thermal conductivity. Additionally, 25 wt.% of turmeric powder (Curcuma) significantly improved shape stability and stopped material leakage across the solid-liquid phase transition of composite PCM. The enhanced thermal conductivity of the composite PCM can be attributed to the development of interconnected percolation networks of CBNP particles with low thermal resistance during the freezing (solidification) of the PCM that provides a more effective phonon transport path. Sustainable energy materials (composite PCMs) with better thermal properties, shape stability, and low cast would be beneficial for practical application suitability and effective energy storage applications.
Investigating the Impact of Water-Glycol Mixture Ratios as Heat Transfer Fluid on the Performance of a Rotary Magnetic Refrigerator
Authors: Bocanegra J A , Scarpa F , Tagliafico L
Published: January 2025

Magnetic refrigeration offers an eco-friendly and sustainable alternative for cooling applications. The selection of an appropriate working fluid is critical for heat removal and regeneration efficiency in Active Magnetic Regenerators (AMRs). This study evaluates various working fluids, focusing on water mixed with an antifreeze agent, glycol, to extend the temperature range and prevent corrosion. The thermophysical properties of such mixtures differ from pure water, influencing the refrigerator’s performance. A parametric investigation using a numerical model of a rotative magnetic refrigerator was conducted to analyze the effects of varying the water-glycol mixture ratios. The study systematically varied operational parameters, such as rotation frequency and mass flowrate, to determine optimal performance conditions. Results indicate that the performance, measured by the Coefficient of Performance (COP), cooling load, and efficiency, declines with increasing glycol content, particularly at lower temperature spans. Increased viscosity in the mixture necessitates higher pumping power and torque for optimal operation, affecting the optimal rotational frequency. This study underscores the importance of balancing the mixture composition to enhance temperature range while minimizing negative impacts on performance, advocating for mixtures with lower glycol content.
Urban Building Energy Modeling for Self-Sufficiency Scenarios with solar technologies in Turin, Italy
Authors: Usta Yasemin , Montazeri Ahad , Mutani Guglielmina
Published: January 2025

Understanding the complexities of building energy dynamics is crucial as it offers a pathway to reducing energy consumption and associated emissions. By using Urban Building Energy Modeling (UBEM), this work aims to drive sustainable urban development, by integrating renewable energy sources in district heating networks. This study focuses on UBEM as an effective scale for analyzing buildings within their specific characteristics that influence their consumptions and limit their production from renewables. The analysis focuses on utilizing solar thermal collectors (STC) for space heating consumption in residential buildings connected to the district heating network. The aim is to allow the integration of renewables into district heating network by testing lower supply temperatures. The validated model is used to analyze the potential self-sufficiency achieved through STC production for all residential buildings in three analyzed zones. The results indicate the potential of achieving self-sufficiency using STCs with different inlet and outlet temperatures; a self-sufficiency of 24% with 90°C and 21% with 105°C supply temperatures in March while for October it could only reach 9% and 7% respectively. The results of this work are crucial for optimizing solar energy production and to explore a distributed production system for individual and collective self-consumption strategies, offering insights into sustainable energy scenarios and policies.
Multiphase boiling models of propane in a horizontal pipe: application of CFD techniques
Authors: Giunti Lorenzo , Gigliotti Federico , Giacomelli Francesco , Talluri Lorenzo , Milazzo Adriano
Published: January 2025

This paper investigates the capabilities of CFD models, available in the commercial software Ansys, used in the study of the propane evaporation heat transfer coefficient trend. In particular, the flow in a horizontal pipe, at various average vapor qualities, has been considered. The scheme adopted in the definition of the problem is based on the Eulerian multiphase approach and RPI-CHF wall heat partitioning. A preliminary benchmark assessment, essential for validating the mathematical model, has been conducted with reference to boiling water in vertical pipes. The prediction is in consistent agreement with experimental results if a modification in some of the fundamental parameters is made. The validation has to be regarded as a propaedeutic study for future research related to more complex geometries, such as channels between corrugated plates of compact heat exchangers.
Unitary branching rules for the general linear Lie superalgebra
Authors: Gould Mark D , Zhang Yang
Published: January 2025

In terms of highest weights, we establish branching rules for finite dimensional unitary simple modules of the general linear Lie superalgebra

gl

m

|

n

. Our proof uses the Howe duality for

gl

m

|

n

, as well as branching rules for Kac modules. Moreover, we derive the branching rules of type 2 unitary simple

gl

m

|

n

-modules, which are dual to the aforementioned unitary modules.
Dunkl symplectic algebra in generalized Calogero models
Authors: Hakobyan Tigran
Published: January 2025

We study the properties of the symplectic

s
p
(
2
N
)

algebra deformed using Dunkl operators, which describe the dynamical symmetry of the generalized N-particle quantum Calogero model. It contains a symmetry subalgebra formed by the deformed unitary generators as well as the (nondeformed)

s
l
(
2
,
R
)

conformal subalgebra. An explicit relation among the deformed symplectic generators is derived. Based on the matching between the Casimir elements of the conformal spin and Dunkl angular momentum algebras, the independent wavefunctions of the both the standard and generalized Calogero models, expressed in terms of the deformed spherical harmonics, are classified according to infinite-dimensional lowest-state

s
l
(
2
,
R
)

multiplets. Meanwhile, any polynomial integral of motion of the (generalized) Calogero-Moser model generates a finite-dimensional highest-state conformal multiplet with descendants expressed via the Weyl-ordered product in quantum field theory.