bluuebunny/crossref_metadata_2025 huggingface dataset:
Interpreting tensor basis neural networks with symbolic transcendental Reynolds stress models for transonic axial compressor flows
Authors: Ji Ziqi , Lu Haomin , Duan Penghao , Du Gang
Published: February 2025

Transonic axial compressor flows exhibit complex turbulence structures that pose significant challenges for traditional turbulence models. In recent years, neural network-based turbulence models have demonstrated promising results in simulating these intricate flows. However, these models often lack interpretability, a crucial aspect of understanding the underlying physical mechanisms. Symbolic regression, capable of training highly interpretable turbulence models, offers a potential solution to elucidate the mechanisms underpinning neural network-based turbulence models. In this study, we employ evolutionary symbolic regression to interpret tensor basis neural networks (TBNNs) and develop explicit transcendental Reynolds stress models (ETRSM) for transonic axial compressor flows. Our symbolic regression turbulence models are trained on the inputs and outputs of a pre-trained TBNN. We introduce a method that independently predicts coefficients for each tensor basis, significantly reducing computational costs and enhancing the rationality of the prediction process. We develop six symbolic regression models: three transcendental and three algebraic. Through rigorous computational fluid dynamics (CFD) simulations, the transcendental models demonstrate an exceptional ability to interpret the TBNN, while the algebraic models show limited success. The symbolic regression ETRSM, characterized by high interpretability and transferability, effectively interprets the pre-trained TBNN and achieves comparable accuracy to TBNN-based turbulence models in simulating the complex turbulence flows in transonic axial compressors. These results underscore the potential of symbolic regression turbulence models for simulating industry-level CFD problems and highlight the importance of incorporating additional features in training such models. Furthermore, the method separates the prediction of individual tensor basis coefficients, significantly reducing computational costs.
Systematic investigation of anomalous Hall effect in Fe–Pt composition-spread epitaxial films for magnetic sensor application
Authors: Patel Akhilesh Kumar , Toyama Ryo , Masuda Keisuke , Simalaotao Kodchakorn , Nakatani Tomoya , Miura Yoshio , Sakuraba Yuya
Published: February 2025

Magnetic field sensors based on the anomalous Hall effect (AHE) require a magnetic thin film with high anomalous Hall resistivity (ρyxA) and moderate perpendicular uniaxial magnetic anisotropy (Ku) to achieve both a large linear sensitivity and a dynamic range (DR) adaptable for various applications. In this study, we fabricate Fe1−xPtx(0≤x≤1) composition-spread epitaxial thin films and systematically investigate the composition dependence of the AHE, aiming to achieve high sensitivity for the magnetic field sensors. We also explore the underlying physical mechanism of the AHE in the Fe–Pt binary system. Structural analysis reveals the [001]-oriented epitaxial growth, featuring distinct phases of A2-Fe, L12-Fe3Pt, L10-FePt, and L12-FePt3 as increasing x along with their mixed-phases, except for the Pt-rich region. Among the entire Fe1−xPtx, an off-stoichiometric Fe-rich composition Fe0.70Pt0.30 exhibits the highest ρyxA of 4.5 μΩ cm with a linear response to the external magnetic field and a DR of 600 mT, yielding a high sensitivity of 8 μΩ cm/T. The DR can be tuned in a wide range from 600 to 1400 mT by changing the Fe:Pt composition ratio, which is attributed to the variation in Ku and magnetization in the Fe–Pt binary alloy system. The anomalous Hall conductivity (AHC) shows an oscillatory variation with composition x, with the largest AHC of 1261 S/cm observed for Fe0.70Pt0.30. The theoretical calculation of the AHC for A2-Fe and L12-Fe3Pt, including the analysis of the density of states for the off-stoichiometric compositions, suggests that the overall variation in AHC with x can be mostly explained by an intrinsic mechanism and the electron doping effect introduced by Pt addition. Theoretical analysis supports that the highest sensitivity obtained in Fe0.70Pt0.30 originates from the large intrinsic AHC (1759 S/cm) predicted for L12-Fe3Pt.
Diagnosis of focal spots at relativistic intensity utilizing coherent radiation from laser-driven flying electron sheets
Authors: Xu Shirui , Pan Zhuo , Gao Ying , Zhao Jiarui , Chen Shiyou , Mei Zhusong , Chen Xun , Peng Ziyang , Liu Xuan , Liang Yulan , Xu Tianqi , Song Tan , Wu Qingfan , Zhang Yujia , Liu Zhipeng , Zhang Zihao , Chen Haoran , Han Qihang , Shen Jundong , Hua Chenghao , Zhu Kun , Zhao Yanying , Lin Chen , Yan Xueqing , Ma Wenjun
Published: February 2025

Experimental validation of laser intensity is particularly important for the study of fundamental physics at extremely high intensities. However, reliable diagnosis of the focal spot and peak intensity faces huge challenges. In this work, we demonstrate for the first time that the coherent radiation farfield patterns from laser–foil interactions can serve as an in situ, real-time, and easy-to-implement diagnostic for an ultraintense laser focus. The laser-driven electron sheets, curved by the spatially varying laser field and leaving the targets at nearly the speed of light, produce doughnut-shaped patterns depending on the shapes of the focal spot and the absolute laser intensities. Assisted by particle-in-cell simulations, we can achieve measurements of the intensity and the focal spot, and provide immediate feedback to optimize the focal spots for extremely high intensity.
The weak form of the phase-field model for grain growth and its application in numerical simulation
Authors: Xie Li , Cai Dan
Published: February 2025

Grain growth is a fundamental process in materials science, influencing the mechanical and physical properties of polycrystalline materials, including electrical conductivity, thermal conductivity, and corrosion resistance. This study focuses on the classical phase-field model for grain growth, systematically deriving its weak form to facilitate numerical implementation in finite element software. The weak form transforms complex partial differential equations into integral forms suitable for numerical solutions, eliminating the need for custom code development and enabling seamless multi-physics coupling. Numerical simulations were conducted in two-dimensional and three-dimensional settings to validate the model’s feasibility and accuracy. The results demonstrate the consistency of grain growth behavior with classical theories, revealing dynamic grain boundary migration and topological changes. This work not only provides a flexible and efficient framework for phase-field simulations but also offers a practical reference for implementing other phase-field models in finite element methods, paving the way for future advancements in materials science.
Translocation of a rehabilitated juvenile platypus (Ornithorhynchus anatinus)
Authors: Thomas Jessica L.
Published: February 2025

The success of rehabilitated juvenile animals after release is poorly studied. This study monitored the behaviour and habitat use of a juvenile male platypus (Ornithorhynchus anatinus) found in poor body condition on a driveway and rehabilitated, before undergoing an inter-catchment translocation. Radio telemetry tracked his movements and resting locations for 18 days during which he used more vegetation for shelter than burrows. After 8 days in the creek near the release site, he travelled through drains into a swamp, potentially displaced by resident platypuses, where the signal was lost. The results demonstrate significant challenges in post-release survival, including burrow creation. This case highlights the importance of monitoring animals after release.
Integrative morphological, mitogenomic and phylogenetic analyses reveal new vent-dwelling scallop species
Authors: Lin Yi-Tao , Peng Ying-Bei , Chen Chong , Xu Ting , Qiu Jian-Wen
Published: February 2025

Delectopecten is a small genus of the family Pectinidae (Bivalvia: Pectinida) that remains poorly studied in terms of both morphology and phylogeny. Here, we describe the first member of this genus from deep-sea hydrothermal vent ecosystems, D. thermus sp. nov., based on morphological investigations and molecular analyses of a specimen collected from the Higashi–Ensei vent field (962-m depth) in the northern Okinawa Trough. Morphologically, this new species resembles D. vancouverensis and D. gelatinosus in shell size, shape, auricle size and sculpture. However, D. thermus sp. nov. can be distinguished from its congeneric species (including 9 extant and 12 fossil species) by its unequal auricles (the anterior one being larger than the posterior), inwardly recurved anterior auricle of the left valve and a large byssal notch angle of ~90°. Comparisons of genetic sequences from three mitochondrial and three nuclear gene fragments supported the placement of the new species in the genus Delectopecten. Further phylogenetic analyses using these gene markers support that Delectopecten is monophyletic and positioned as an early diverging clade of the family Pectinidae. Additionally, the mitogenome of D. thermus sp. nov. was assembled and annotated, a first for its genus – revealing significant divergences in gene order compared to other pectinids. The 16S rRNA amplicon analysis of the gill tissue indicated that this vent-dwelling scallop does not exhibit symbiosis with chemosynthetic bacteria. A key to all known species of Delectopecten is provided to aid the identification of species in this understudied genus. ZooBank: urn:lsid:zoobank.org:pub:D3D5D4AD-EE39-49F0-9782-12A5D6752A67
Identification of FSH-regulated and estrous stage–specific transcriptional networks in mouse ovaries
Authors: Walters Kathryn , Baldwin Amber , Liu Zhenghui , Larsen Mark , Mukherjee Neelanjan , Kumar T. Rajendra
Published: February 2025

Follicle-stimulating hormone (FSH) acts by binding to FSHRs expressed on ovarian granulosa cells and produces estradiol. FSH is essential for female fertility because mice lacking FSH (
Fshb KO
) are anestrous and infertile. Although several in vitro cell culture and ex vivo approaches combined with pharmacological hormone treatment were used to identify FSH-regulated genes, how FSH orchestrates ovarian gene networks in vivo has not been investigated. Whether FSH-regulated genes display estrous stage–specific expression changes has also not been studied. Here, we functionally rescued
Fshb
null mice with a gonadotrope-targeted
HFSHB
transgene and performed RNA-Seq analysis on ovarian RNAs obtained from FSH-intact (
WT
), FSH-deficient (
Fshb KO
), and FSH-rescue (

HFSHB
+

rescue) mice. By comparing
WT
vs.
Fshb KO
and
Fshb KO
vs.

HFSHB
+

rescue ovarian gene expression datasets, we identified FSH-responsive genes in vivo. Cross interrogation of these datasets further allowed us to identify several transcription factors (TFs) and RNA-binding proteins specific to FSH-regulated genes. In an independent set of experiments, we performed RNA-Seq analysis on ovarian RNAs from mice in diestrous (DE), proestrous (PE), and estrous (E) and identified estrous stage–specific ovarian gene expression patterns. Interestingly, many of the FSH-regulated TFs themselves were estrous-stage specifically expressed. We found that ESR2 and GATA6, two known FSH-responsive TFs, and their target genes are reciprocally regulated with distinct patterns of expression in estrous stages. Together, our in vivo models and RNA-Seq analyses identify FSH-regulated ovarian genes in specific estrous stages that are under transcriptional and posttranscriptional control.
Thermoelastic twisting–assisted crystal jumping based on a self-healing molecular crystal
Authors: Wang Zhihua , Cheng Puxin , Han Wenqing , Shi Rongchao , Xu Jian , Zheng Yongshen , Xu Jialiang , Bu Xian-He
Published: February 2025

Adaptive crystals have attracted significant attention from solid-state chemists and crystal engineers for their promising applications in memories, capacitors, sensors, and actuators. Among them, thermosalient crystals are particularly favored thanks to their efficient energy conversions and rapid responses. However, the mechanisms for the mechanical responses of thermosalient crystals remain largely unclear. Herein we demonstrate that thermosalient effects of molecular crystals could be driven by thermoelastic twisting behaviors. The crystal, based on a model compound with rigid dibenzothiophene sulfone planes and flexible ethoxy chains, can spontaneously self-heal from mechanical fractures. Upon heating, the crystal undergoes remarkable thermosalient behaviors driven by a distinctive left- or right-handed twisting. This thermoelastic twisting converts thermal energy into elastic potential energy, which is further released as kinetic energy upon untwisting to drive the crystal jump. Our demonstration on thermoelastic twisting–induced crystal jumping offers a different perspective on the origins of thermosalient crystals and could provide inspiration for future engineering and application of dynamic molecular crystals.
Human-animal bonds and mental health: Examining the roles of bond strength, interactions, and attachment security
Authors: Orlando Elizabeth M. , Chin Brian N.
Published: February 2025

This study examines how human-animal bonds and interactions impact human mental health. We hypothesized that stronger and more secure human-pet bonds and more frequent interactions would improve mental health, and that more frequent human-pet interactions would correlate with stronger and more secure human-pet bonds. We conducted a secondary analysis of data from 1028 US adults with pets who completed questionnaires assessing bond strength, pet interactions, and depression symptoms. Our results indicated that higher pet attachment anxiety was the only significant predictor of prevalent depression symptoms. Additionally, more frequent interactions with pets (e.g., affection, play) were linked to stronger and more secure bonds. Participants owning both cats and dogs reported more depression symptoms than those who owned cats or dogs only but pet type did not influence bond strength, security, or interaction frequency. These findings highlight attachment anxiety as a key characteristic of human-pet relationships that underlie their impact on mental health. Future research should explore whether fostering a more secure human-pet bond by increasing the frequency of pleasant human-pet interactions and whether human mental health can be improved by fostering a more secure bond with pets.
Diatomic molecule in the polar trap
Authors: Yaremko Yurij , Przybylska Maria , Maciejewski Andrzej J
Published: February 2025

We discuss the trapping of heteronuclear diatomic molecules prepared in their electronic and vibrational ground states. We tune and shape the trapping potential for bosonic polar molecules in superpositions of rotational states by dressing rotational excitations with a static sextupole electric field. The translational motion of a molecule is treated classically. We examine the Hamiltonian which governs the center of mass dynamics. The effective potential has a global minimum that provides the trapping ability of this trap. The first term of its Taylor series expansion, corresponding to the quadratic Stark shifts, results in the integrable potential. In terms of cylindrical coordinates the center of mass Hamiltonian splits into axial and radial parts. Corresponding trajectories are parameterized by elliptic functions. At low electric fields, the non-approximated Hamiltonian is treated as a small perturbation of the mentioned integrable system described by Kolmogorov–Arnold–Moser theory. The applicability of this approximation is discussed and illustrated using the Poincaré cross-section method. We present results of numerical simulations illustrating the trapping and confinement of a polar molecule in the trap.
Tar destruction using non-thermal plasma technology—a critical review
Authors: Pathak Ram Mohan , Jayanarasimhan Ananthanarasimhan , Rao Lakshminarayana
Published: February 2025

Tar, a by-product of gasification, is a complex mixture of high molecular weight hydrocarbons that can cause significant damage to downstream equipment and reduce the efficiency of gas utilization. Effective tar destruction is therefore essential for producing clean syngas. Non-thermal plasmas (NTP’s) technology offers a promising solution for gas cleaning by effectively destroying tar. This review explores various plasma sources and experimental approaches for using NTP’s in tar destruction. It evaluates the performance of different plasma sources on the destruction of toluene and naphthalene, the most prevalent tar compounds in gasifier product gas, and discusses the chemical mechanisms and modeling approaches involved in their destruction. The most common modeling approach includes reaction kinetics, demonstrating how chemical reactions occur and behave in the NTP’s system. This approach, known as the plasma global model, simplifies plasma modeling by focusing on reaction rates to predict the production and loss of species without needing to model plasma’s bulk properties. The works that investigated plasma-catalysis for tar destruction were considered. A comparison of literature works reveals that the best performance for naphthalene destruction is achieved by corona plasma and reverse vortex flow gliding arc reactors, with the destruction efficiency

(

η
d

)

of 99% and 99.8% at concentrations of 5 g m−3 and 10.3 g m−3, respectively. For toluene, the gliding arc discharge and rotating gliding arc combined with the catalyst demonstrate the highest efficiency, achieving 99% and 99.9% destruction at 22.9 g m−3 and 4 g m−3, respectively. The synergy between plasma and catalysts offers key benefits, including higher energy efficiency, faster reactions, and lower operating temperatures compared to traditional thermal methods. The review suggests that NTP’s technology shows strong potential for removing biomass tar from gasification. It could be a promising solution for biomass tar cracking and upgrading product gas in real gasification applications. Several pilot and small-scale plasma plants have been developed, but the technology is still emerging and faces various technical and economic challenges.
Recent progress in non-equilibrium structure and dynamics of connected active agents
Authors: Zhang Yanfang , Tian Wen-de
Published: February 2025

Active agents, which convert energy into directed motion, are inherently non-equilibrium systems. Inspired by living organisms and polymer physics, connected active agents with various topologies have recently garnered significant attention. These agents have positional degrees of freedom with well-defined topologies, while activity introduces extra degrees of freedom. The intricate interplay of activity, elasticity, noise, and conformational degrees of freedom gives rise to novel non-equilibrium behaviors in chain-like structures. This review categorizes active agents into three types based on their alignment mechanisms: Active Brownian agents, Vicsek-type agents, and self-aligning agents. It further provides the results when these agents are connected through different topological structures in two-dimensional spaces, at interfaces, in three-dimensional environments, and under confinement. The goal is to shed light on the fundamental physics that govern their non-equilibrium behavior at the level of individual chains and to highlight potential research directions. These findings hold significant potential for advancing the design of metamaterials and swarm robotics.
Preparation of aggregation-free ZnPc-doped nanophotosensitizers for highly efficient photodynamic therapy
Authors: Zhang Yafei , Bo Bingyang , Qin Jinglei , Liu Bei , Peng Hong-Shang
Published: February 2025

Zinc phthalocyanine (ZnPc), a promising second-generation photosensitizer, suffers from decreased quantum yield of singlet oxygen due to poor water solubility and prone-to-aggregation nature in both physiological environment and solid matrix. To address this issue, in this work we reported a simple ligand-assisted reprecipitation method to prepare aggregation-free ZnPc-doped nanoparticles (NPs). Specifically, a short-chain ligand hexylamine was introduced to coordinate with ZnPc during reprecipitation, so that to alleviate ZnPc aggregation in the polymeric nanomatrix. As a consequence, the as-prepared ZnPc-loaded NPs with an optimal loading content of 4 wt.% acquired a high singlet oxygen quantum yield (ΦΔ) of 0.5, which was comparable to that of ZnPc monomer (ΦΔ = 0.55). Moreover, 10 wt.% ZnPc-loaded NPs could still retain a singlet oxygen quantum yield of 0.38. Taking advantage of the aggregation-free nano-photosensitizers (NPSs), efficient photodynamic therapy effect was achieved on HeLa cells upon 660 nm photo-irradiation with an ultra-low light dose (1.8 J cm−2). This study not only presented a high efficient ZnPc-based NPS, but also proposed a new strategy to reduce the aggregation of metal complex in solid matrix through ligand coordination.
Development of fluorine-free fluorescent coatings with carbon dots and silica for superhydrophobic aluminum alloy surfaces
Authors: Peng Huaqiao , Li Wenyan , Liu Xueqi , Li Tao , Liu Xiwen , Li Zhi , Liu Yourui , Shi Tao
Published: February 2025

Superhydrophobic surfaces attract increasing attention, and they have been widely studied because of their excellent anti-icing, anti-corrosion, self-cleaning, and oil–water separation properties. In this study, a robust hierarchical structure was prepared on an Al-alloy substrate by spraying a mixture of epoxy resin (EP), hydrophobic SiO2, and styrene-ethylene-butyrene-styrene (SEBS) to realize superhydrophobicity. In addition, carbon dots (CDs) with fluorescence were incorporated to detect micro-coating damage in practical applications. The as-prepared superhydrophobic surface of EP-Si@CDs exhibited a high water contact angle of ∼165.2° and a low sliding angle of ∼7.6°, in addition to good non-wettabilities toward common liquid droplets. The superhydrophobic EP-Si@CDs surface was characterized using scanning electron and laser scanning confocal microscopy, energy-dispersive x-ray and x-ray photoelectron spectroscopy to investigate its structure and chemical composition. Meanwhile, superhydrophobic EP-Si@CDs displayed good durability, with the contact angle remaining at >150° and the sliding angle remaining at <10° after dragging for 280 cm under a mass of 100 g. Owing to the incorporation of the CDs, EP-Si@CDs emitted a bright yellow fluorescence under ultraviolet light, which could be used to detect micro damage. EP-Si@CDs exhibited excellent anti-icing and self-cleaning performances, and the related mechanisms were investigated in detail.
Evaluation of the spatial resolution of the peeled-off Gafchromic EBT2 film irradiated with different doses of low-energy alpha particles from 241Am
Authors: Mohamed Amal , Ghaith M S , El Ghazaly M , Kelany Nermeen A , Ibrahim Manar A , El-Naggar Hala I , Al-Sayed A
Published: February 2025

In the current study, the edge spread function, the spatial resolution (σ), and the response of Gafchromic EBT2 film to low-energy alpha particle doses were investigated. The Gafchromic EBT2 films were peeled-off to permit the 4 MeV alpha particles to reach the active layer. The peeled-off Gafchromic EBT2 films were irradiated with different doses of 4 MeV alpha particles from 241Am, where a razor blade was kept in close contact with the active layer in the middle of the alpha particles beam to produce two distinct halves (edges). The measured edge spread function (ESF) for different color channels as well as the weighted and unweighted gray images were fitted using the error function and thereafter differentiated to produce the line spread function (LSF). The blue channel exhibits an anomalous response to the 4 MeV alpha particle dose, leading to a dynamic range reduction of the peeled-off Gafchromic EBT2 film. The pixel values of red and green channels decrease by increasing alpha particle doses, with a descending sensitivity at higher doses. The pixel values of weighted and unweighted gray images decrease with the increase in alpha particle doses but with lower sensitivity. The spatial resolution of the peeled-off Gafchromic EBT2 film is independent of the 4 MeV alpha particle doses for red, green color channels, and weighted and unweighted gray images; the spatial resolution is close to that of single-color channels but with less contrast and visibility. The average spatial resolution, within the same channel, in terms of 1σ (standard deviation), amounts to (21.9 ± 1.5), (19.5 ± 1.4), (19.4 ± 1.3), and (19.4 ± 1.3) μm for red and green channels, weighted and unweighted gray images, respectively. Finally, the LSF peak was found to be proportional to the associated absorbed dosage. This can be utilized for forecasting the alpha-particle absorbed dose within the boundaries of the current study.
Silica/magnetite core-shell nanostructures as pH-dependent quartz crystal microbalance sensors for nickel ion detection in aqueous solutions
Authors: M Saad Almontaser Ballah , El-Mehalmey Worood A , El-Sherif Rabab , Salem Mohamed Shaker
Published: February 2025

Herein, we report the controlled formation of silica/magnetite core–shell nanostructures and their potential utilization as sensors for the real-time detection of nickel ions with different concentrations in aqueous solutions. Nickel ions were presented in this work as example of contaminants. When coupled with quartz crystal microbalance (QCM) technology, the prepared core–shell nanostructures were found to exhibit high sensitivity and a prompt response toward the presence of nickel ions in an aqueous environment. The robust structure of the silica core and the increased surface area provided by the magnetite shell enhance the adsorption of metal ions. The pH of the solution was found to have a strong impact on the sensing performance of the core–shell structure. Optimal sensor performance was observed at neutral pH, demonstrating the potential of this system for continuous environmental monitoring of nickel ions pollutants.
Effective description of the quantum damped harmonic oscillator: revisiting the Bateman dual system
Authors: Javier Valdez C R , Hernandez-Hernandez H , Chacón-Acosta G
Published: February 2025

In this work, we present a quantization scheme for the damped harmonic oscillator (QDHO) using a framework known as momentous quantum mechanics. Our method relies on a semiclassical dynamical system derived from an extended classical Hamiltonian, where the phase-space variables are given by expectation values of observables and quantum dispersions. The significance of our study lies in its potential to serve as a foundational basis for the effective description of open quantum systems (OQS), and the description of dissipation in quantum mechanics. By employing the Bateman’s dual model as the initial classical framework, and undergoing quantization, we demonstrate that our description aligns exceptionally well with the well-established Lindblad master equation for the QDHO. Furthermore, the robust formulation of our approach suggests a broad applicability in the context of OQS, extending implementations into more general systems, making it a versatile and powerful tool to study diverse phenomena.
Polarization and Interstellar Extinction Towards the Open Star Cluster NGC 6633
Authors: Topasna G. A. , Kirk N. E. , Kaltcheva N. T.
Published: February 2025

We present optical polarization data of 110 stars in the direction of NGC 6633. From multi-wavelength BVRI measurements of 64 of these stars we obtained a wavelength of maximum polarization that yielded an estimate of total-to-selective extinction ratio R

V
 = 3.18 ± 0.04 over the observed region. The distribution of the polarization position angles overall reveals a fairly uniform Galactic magnetic field. The fractional V-band polarization of the cluster’s members is between 0.8% and 1.4%, clearly above the 0.5% average value measured for the nearby field stars in the sample. We analyze the V-band polarization and maximum polarization as a function of color excess and extinction based on dust maps, Gaia, and uvbyβ photometry to discuss the polarization efficiency. The interpretation depends on the set of color excess or extinction data used, but for the majority of stars the polarization is confined below the empirical p
max ∼ 9%E(B − V) upper limit for the maximum polarization. On average, the normalized Stokes parameters show a slight offset of the foreground and background stars in comparison to the cluster’s members, but a significant overlap for many stars along the line of sight is present. We discuss a comparison of our optical polarization measurements to the Planck data in the context of the interpretation that the dust causing the infrared emission is also responsible for the optical polarization. We suggest that the polarization we measure for stars at the cluster’s distance around 400 pc is due to foreground dust between 100 and 350 pc and that multiple clouds along the line of sight could be the reason for some of the variations we observe.
The Synchronization of Time for VLBI Observations
Authors: Liu Lei , Zhang Juan , Ma Maoli , Zheng Weimin
Published: February 2025

For some space radio telescopes, the orbit determination accuracy is not high enough, the time synchronization accuracy provided by the satellite platforms is low, and GNSS devices are not available. As a result, a traditional method that relies on GNSS devices to obtain an initial clock offset followed by performing correlation with the calibration source may fail to obtain fringes. Moreover, a brutal force search across the 2D clock offset and fringe rate search plane is computationally expensive. In light of these challenges, we propose a novel time synchronization method that utilizes the spacecraft’s telemetry tone signal. This method employs frequency polynomials derived from Doppler tracking for fringe rotation during the correlation process. By aligning the frequency of the target station precisely with that of the reference station, it is only necessary to split the clock offset search range into multiple time windows, perform correlation for each window, and identify the window with the highest signal-to-noise ratio (SNR). The precise clock offset is determined by combining the residual delay with the initial offset. To validate the method, we observe the Tianwen-1 telemetry signal with the 4.5 m small telescope in the Tianma campus of Shanghai Astronomical Observatory and 40 m telescope in Kunming. The results demonstrate that our method can accurately determine clock offset for a time range as wide as  ±10 ms, with an SNR slightly higher than that achieved with the delay model. This method is suitable for wide-range time synchronization for space Very Long Baseline Interferometry observations, especially in scenarios involving small antennas with low sensitivity and poor orbit determination accuracy.
A Changeable Frequency Control Strategy Coordinated with Black Start for Photovoltaic Station Integrated with Energy Storage
Authors: Ke Song , Yang Jun , Peng Xiaotao , Chen Lei , Liang Jifeng , Yu Tengkai , Liao Fei
Published: February 2025

To enable Photovoltaic (PV) a controllable unit for frequency regulation and black start in power system, a grid-forming frequency control strategy is designed for PV station integrated with storage (ES). This paper proposed a frequency control strategy for PV and ES is developed based on virtual synchronous generator (VSG) control. Then, a small signal modeling of PV-ES control system is deduced with stability analysis. The simulation results reveal the feasibility and effectiveness of the proposed control method of PV and ES integration in frequency response.
Accelerated adiabatic dynamics of two level system of Dirac particle
Authors: Setiawan Iwan , Ekawita Riska , Sugihakim Ryan , Eka Gunara Bobby
Published: February 2025

We study a scheme to accelerate adiabatic quantum dynamics of Dirac particle. This scheme using the strategy of combining two opposite ideas: infinitely-large time-magnification factor (𝛼̅) and infinitely-small growth rate (𝜖) of adiabatic parameter. The accelerated adiabatic state is obtained by obtaining the regularization term and driving potential. We introduce the proposed method to the system of two level systems of Dirac particle by using a (1 + 1) dimension time dependent Dirac equation and obtained the regularization term. By tuning the driving magnetic field, this method to be able to accelerate adiabatic dynamics of electron as a Dirac particle in the ground state that considered as a two level system. This acceleration will preserve the ground state of the wave function from initial to the final time.
Numerical Study of Thermodynamic Properties of Screened Kratzer-Eckart Potential with External Magnetic Field
Authors: Nur Setyanto Firda , Wibawa B.S.H. , Suparmi A. , Cari C. , Lestari D.
Published: February 2025

Attempts to understand the behaviour of various quantum systems are still become interest for many researchers in recent years. While experimentation is too complicated to be done, analytical mathematical approach is become a reliable choice. This approach is using potential functions or models as representations of the real quantum system, such as physical force interactions within a molecule. In this study, the new combination model of screened Kratzer and screened Eckart potentials is investigated under the non-relativistic quantum mechanics framework. These potentials are well-suited for modelling atomic interactions in diatomic molecules. The primary objective is to examine how these interactions are affected by the presence of external magnetic fields. Using a specific form of the Schro dinger equation, both the energy eigenfunction and the wave function have been derived. The Nikiforov-Uvarov Functional Analysis (NUFA) method was employed for this derivation. Additionally, several thermodynamic properties were obtained from the energy equation using numerical methods. Selected diatomic molecule data were used in the computations to demonstrate the effect of the magnetic field. A detailed analysis was performed through graphical representations, revealing that an increase in the magnetic field or the associated Aharonov-Bohm (AB) flux enhances and splits the energy spectra. The effects on thermodynamic properties vary across different molecules and conditions, but overall, the magnetic field increases the thermodynamic properties of the molecules.
Modification of the working electrode using Silver Nanoparticle (AgNP) doping to enhance the efficiency of Dye-Sensitized Solar Cells (DSSC)
Authors: Dwi Apriliani Putri Tasya , Nurosyid Fahru , Iriani Yofentina , Suryana Risa
Published: February 2025

This study investigated the effects of silver nanoparticles (AgNPs) doping concentrations of 0%, 5%, and 10% on the photoanode to enhance the performance efficiency of Dye-Sensitized Solar Cells (DSSC). Silver nanoparticles (AgNP) were synthesized from silver nitrate solution (AgNO3) with a green synthesis method using andrographis paniculata (Sambiloto) leaf extract, which acts as a bio-reductor. Andrographis paniculata leaves were chosen due to their andrographolide content, which serves as an effective bio-reductor. The AgNPs were incorporated in TiO2, functioning as the working electrode. The dye utilized was Ruthenium Complex N719, with Platinum (Pt) as the counter electrode. Both the photoanode and counter electrodes were deposited on the substrates using the spin coating method. Scanning Electron Microscope (SEM) tests revealed morphological photoanode. Additionally, Ultraviolet-Visible (Uv-Vis) spectroscopy indicated absorbance and band gap energy values. Specifically, the bandgap energies were 3.284, 3.271 eV, and 3.250 eV for Ag doping concentrations of 0%, 5%, and 10%, respectively. This study found that Ag doping at a 5% concentration significantly enhanced efficiency compared to 0%, where the highest efficiency was achieved by this sample. Nevertheless, Ag doping with 10% concentration caused a decrease in efficiency due to particle agglomeration. These findings were corroborated by I-V Meter characterization, which measured the photovoltaic performance. The efficiency values were 0.097%, 0.798%, and 0.367% for doping concentrations of 0%, 5%, and 10%, respectively. The results suggest that an optimal doping concentration of AgNP can significantly improve the efficiency of DSSC.
A Multi-Criteria Decision Support System for Prioritizing Road Maintenance: Integrating AHP and TOPSIS with a Focus on Low-Volume Roads
Authors: Chaipetch Pawarotorn , Amprayn Chisanu , Pawan Paijit , Ratanavaraha Vatanavongs
Published: February 2025

The Department of Rural Roads (DRR) in Thailand manages an extensive network of over 48,974 kilometers of roads. Traditionally, budget allocation for road maintenance has been primarily based on traffic volume and the International Roughness Index (IRI), often neglecting low-volume roads crucial for rural connectivity and development. To address this limitation, a decision support system (DSS) was developed, integrating the Analytical Hierarchy Process (AHP) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). AHP facilitated the determination of the relative weights of economic, engineering, environmental, and social factors in road maintenance decisions. Subsequently, TOPSIS was employed to rank and prioritize road sections for maintenance based on their performance across these criteria. The DSS was evaluated using data from 724.124 kilometers of road and a budget of 4,078 million baht. The evaluation revealed that while prioritizing Benefit-Cost (B/C) Analysis resulted in a greater reduction in IRI, it often overlooked low-volume roads. In contrast, the AHP-TOPSIS method offered a more balanced approach, allocating the budget across diverse road categories and strategic objectives. The findings underscore the value of the AHP-TOPSIS-based DSS as a tool for road maintenance prioritization, particularly for agencies tasked with managing extensive road networks with varying traffic volumes and strategic importance.
The Evolution of the CJEU Case Law on Data Retention
Authors: Kosta Eleni
Published: February 2025

In the European Union, legislative efforts to regulate data retention in 2006 via the Data Retention Directive were subsequently thwarted by the ruling of the Court of Justice of the European Union (CJEU) in the Digital Rights Ireland case. The CJEU received thereafter numerous questions on data retention on the basis of Article 15(1) of the ePrivacy Directive. In Tele2 Sverige, the CJEU linked the issue of data retention with the subsequent access to these data by law enforcement authorities, introducing key safeguards for such access, an approach that the CJEU consistently followed in its subsequent case law on data retention. Chapter 2, through a critical examination of the rich case law of the CJEU, distils the requirements and safeguards introduced by the CJEU in relation to various types of data and for specific purposes. It concludes that the European legislator can rely on these as the basis for a new legislative framework, which covers both the data retention obligations on providers and the safeguards on the access to the retained data.
Data Retention and the Judicial Parameters of Mass Surveillance in EU Law
Authors: Mitsilegas Valsamis
Published: February 2025

Chapter 3 will focus on the evolution of the CJEU case law on data retention, by providing a step-by-step analysis of how the Court of Justice of the European Union has developed parameters to mass surveillance in the face of pressure by Member States. Litigation has been ongoing in view of the reluctance of Member States to accept the limits placed by the Court to mass surveillance based on indiscriminate, generalised data retention. The Court’s annulment of the Data Retention Directive has been followed by repeated references by national courts on the compatibility of national data retention schemes, in the absence of an EU instrument on data retention, with EU law including the Charter of Fundamental Rights. The key features of this judicial evolution will be analysed in the Court’s attempt to protect fundamental rights in the face of considerable pressure by the executive to limit protection on security grounds. The chapter focuses on landmark judgments of the CJEU including Digital Rights Ireland, Tele2 Sverige, and La Quadrature du Net, and subsequent case law, and assess the extent to which the evolution of the Court’s case law continues to provide effective fundamental rights safeguards against mass surveillance. The chapter highlights the significance of the CJEU persistence in upholding fundamental rights by setting limits to mass surveillance, while highlighting the contested nature of the relationship between security and fundamental rights protection in the field of data retention.
Data Retention in Ireland
Authors: McIntyre TJ
Published: February 2025

Chapter 10 examines the development of data retention in Ireland following the CJEU judgments in Digital Rights Ireland and Tele2 Sverige. It describes how the Irish State continued to enforce national data retention law for six years after Tele2 Sverige confirmed its illegality, attempted to re-litigate the legality of indiscriminate data retention before the national courts, and reformed domestic law only when forced to act by the CJEU decision in Garda Síochána. It assesses how national oversight mechanisms largely failed to address this illegality and argues that the data retention saga has highlighted significant weaknesses in the criminal justice system, the ‘designated judge’ model of supervising surveillance, and the accountability of the executive to parliament.
Data Retention Amid the Erosion of the Constitutional Order
Authors: Brewczyńska Magdalena
Published: February 2025

Chapter 12 explores the rule of law crisis Poland has been facing since the victory of the PiS party in the 2015 elections. Despite heavy criticism from both national and international experts and expert bodies on democracy, many controversial legislative reforms have been passed, considerably undermining the principle of the rule of law. In these circumstances, the regulatory developments and uncontested practices concerning the retention of telecommunication data, which date back to the governments of other political forces preceding PiS, might have passed unheeded. Their significance may seem limited in light of the Pegasus scandal and the gravity of the dismantlement of the constitutional order in areas such as the judiciary, freedom of expression, or protection of the rights of minorities. Yet, this contribution shows that the discussion on data retention, albeit overshadowed by many other severe abuses of power, is not trivial and that the concerns it raises show their true colours exactly when democracy and the rule of law are in danger.
Data Retention and Law Enforcement in the Netherlands
Authors: van der Ham Marc , Baars Esther
Published: February 2025

The Netherlands presently lacks a general legal data retention obligation. Chapter 14 chronicles the implementation of the Data Retention Directive into domestic law and explains why its national implementation in the Netherlands was suspended following the Digital Rights Ireland ruling in a case initiated by Privacy First cs in summary proceedings at the District Court of The Hague. It examines subsequent legal initiatives aimed at reinstating a general data retention obligation to benefit law enforcement in investigating and prosecution serious crimes and addressing challenges related to Carrier-Grade NAT technology for associating specific IP addresses with specific users. Additionally, it briefly analyses the policy stance of the Netherlands in the ongoing EU data retention debate.
Regulating Access
Authors: Newell Bryce Clayton
Published: February 2025

In contrast to legislative efforts to regulate data retention in the European Union, legislation in the United States has focused on regulating access to communications data (including metadata and subscriber/user information) without any overarching data retention requirements. In the US, there is no broad data retention law at the federal level. Instead, decisions about data retention are largely left to private companies, and where legislation does exist it is targeted very narrowly (for example, banking information). The primary purpose of this short chapter is to summarize the US approach to regulating access to, rather than retention of, communications data. The chapter seeks to provide an overview of the US approach for scholars and professionals who may be more expert in the European context, and it includes some brief comparisons to the data retention jurisprudence of the CJEU on data retention.
Passenger Name Records
Authors: Haitsma Lucas M , Gstrein Oskar J , Winter Heinrich
Published: February 2025

Chapter 23 examines whether the PNR Directive—lately in the centre of the judgment Ligue des droits humains—is as such compatible with the rights to privacy and data protection. In this judgment from 21 June 2022, the Court of Justice of the European Union (CJEU) introduced several measures seeking to align the Passenger Name Record (PNR) Directive with these fundamental rights. This includes more precise definitions of various provisions, effectively reducing the scope of the Directive, as well as the length of the data retention period. The judges also impose several safeguards pertaining to the collection, processing, and retention activities, notification of passengers, automated processing, and the non-automated review of positive matches. This chapter considers these measures introduced by the CJEU in light of established data retention case law. Furthermore, it examines whether the PNR Directive remains fit for the purposes of combating serious crime and terrorism. In conclusion, we argue that the CJEU aims to introduce several commendable measures to ensure compatibility with fundamental rights, yet seemingly ignores a more fundamental concern: in its current form the PNR system as such appears unfit for the purpose of combating serious crime and terrorism.
Data Retention and Automated Processing of Personal Data
Authors: Vavoula Niovi
Published: February 2025

The case law of the Court of Justice of the European Union (CJEU) on data retention has revealed numerous disproportionate practices at the national level concerning the processing of personal data. One such practice, examined in La Quadrature du Net ‘I’, concerns automated analysis of telecommunications metadata, where the CJEU has proclaimed a series of necessary safeguards that must apply. Chapter 24 aims to examine the CJEU’s approach on automated processing of personal data by examining the standards in that judgment and how these were informed and subsequently further developed by the relevant case law on the automated processing of Passenger Name Records (PNR) data. It thus critically assesses the judgments within the broader jurisprudence on automated processing of personal data, examines the potential applicability of the safeguards in other contexts and positions the case law in light of the LED and the AI Act.