bluuebunny/crossref_metadata_2025 huggingface dataset:
Water wave diodes
Authors: Han Linkang , Ge Zixun , Liao Junke , Chen Huanyang
Published: February 2025

Seaports are crucial components of maritime transportation systems. However, the presence of water waves significantly affects the speed and stability of vessels passing through ports, reducing the port efficiency. Traditional methods of blocking waves are not feasible since they also impede vessel passage. Therefore, finding a solution that effectively mitigates water wave impact while allowing unhindered vessel passage is of paramount importance in maritime transportation. In this article, we introduce a gradient refractive index profile into water wave manipulation and design a novel waveguide isolator device. It functions similarly to an electrical diode, allowing water waves to pass in one direction while blocking them in the opposite direction. Moreover, its waveguide-like hollow structure enables it to block water waves without hindering the passage of vessels. We elucidate the wave-blocking mechanism through mode analysis and numerical simulations, and experimentally validated the device, observing a significant “water wave diode effect.” This effect effectively blocks water waves in one direction while allowing passage in the other. This is the first time that blocking water waves without hindering vessel passage has been realized in the experiment, showing great potential for applications in maritime ports and ocean freight transport.
Lagrangian characterization of induction and reaction timescales in a cellular gaseous detonation
Authors: Watanabe Hiroaki , Matsuo Akiko , Chinnayya Ashwin , Itouyama Noboru , Matsuoka Ken , Kasahara Jiro
Published: February 2025

A Lagrangian approach was proposed to analyze induction and reaction times in the cellular gaseous detonation. Two-dimensional simulations in an argon-diluted and non-diluted hydrogen-based mixtures were performed with detailed chemistry, along particle trajectories. The distribution of the induction and reaction times inside the cell was significantly different between the Eulerian and the Lagrangian perspectives, the latter showing non-monotonic behavior. Preferential thermodynamic paths laid along the Rankine–Hugoniot curve and behind transverse waves (TW). All particles were ignited within half and one cell cycle for the diluted and non-diluted mixture, respectively. The ignition mechanisms were not only one-dimensional, but also multi-dimensional, with ignition behind the TW being the most important, and collision of TW and triple points being secondary. A new topology inside the cell could be drawn, from the intersection of the ignition front with TW. TW appeared as phase waves in the (x,t) diagram. Comparison of H2O mass fraction between local and equilibrium values indicated that a local chemical disequilibrium remained (superequilibrium), due to TW. Equating the mean sonic plane with thermochemical equilibrium in the non-diluted case is not completely accurate. Furthermore, the characteristic time scales for chemical and hydrodynamic phenomena were compared. The diffusive phenomenon did not make any contribution in the mixtures tested. In comparison with the Zel'dovich–von Neumann–Döring model, a shorter average induction time was found in the non-diluted mixture, which is not in line with the results from previous Favre approaches. The average reaction time was also shorter in both mixtures.
A high-order immersed boundary method with ghost cells and flux reconstruction for inviscid flows
Authors: Shen Tong , Lian Yixuan , Cai Jinsheng , Liao Fei
Published: February 2025

We propose a high-order immersed boundary (IB) method for simulating inviscid flows using the flux reconstruction (FR) method, which offers the advantages of a compact stencil, high-order near-wall accuracy, and the ability to handle thin geometries and sharp corners. We utilize the FR method on a Cartesian grid to achieve a compact stencil, which enhances accuracy without requiring surrounding cell information, laying the foundation for future adaptive mesh refinement. Compared to the symmetry wall condition treatment, we combine the curvature corrected symmetry technique with the FR-based IB method to achieve a high-order accuracy near the wall boundary and utilize a third-order polynomial distribution to impose the boundary conditions. We extend the multi-valued ghost-cell method to the present approach to handle thin geometries and sharp corners in the ghost-cell-based IB method. The proposed method can be easily extended to three-dimensional cases. The numerical framework is validated through several two-dimensional simulations of inviscid flows. The approach is first demonstrated for a superposition of an isentropic vortex and a background flow problem with a Mach number of 0.2, which examines the order of accuracy without wall effects in the grid convergence study. Then, inviscid flow around a cylinder and flow through a channel with a bump are tested and compared to body-fitted simulations. Finally, flows around a National Advisory Committee for Aeronautics 0012 airfoil with zero and non-zero angles of attack are demonstrated to show the robustness for the thin geometry calculation. In particular, third-order accuracy is maintained in the near-wall region.
Flow instability caused by temperature boundary conditions in a model of Czochralski crystal growth
Authors: Grants I. , Pal J. , Tsiapkinis I. , Eckert S. , Gerbeth G. , Raebiger D. , Dadzis K.
Published: February 2025

A weakly turbulent buoyancy-driven flow is studied experimentally and numerically in a liquid metal cylinder with small height-to-diameter ratio. The cell represents a model of the Czochralski crystal growth process and includes heating at the bottom and non-uniform cooling at the top. Transition to a non-axisymmetric roll-like flow structure (wind) is observed experimentally under conditions, which still produce a nearly axisymmetric flow in the computations. It is shown that the contradiction can be explained by the flow sensitivity to temperature boundary conditions at the cell bottom. It is made of a massive copper disk to approximate isothermal temperature conditions. Due to a finite heat conductivity, the bottom is unable to sufficiently equalize the temperature over large distances. This deviation from isothermal conditions is amplified in a separate experiment by a thin heat barrier at the cell's bottom. In this case, the transition to wind is observed at a nearly ten times lower heat flux both in numerics and experiment. The transition then produces a very long-period flow oscillation as the wind erratically changes flow direction.
Response and stall mechanism for axial compressor under rotating inlet distortion
Authors: Ma Shuai , Wang Zhiqiang , Hu Jun
Published: February 2025

For multi-shaft aero-engines, the downstream compressor inlet will be exposed to rotating inlet distortion once rotating stall occurs in the upstream fan or low-pressure compressor. In this paper, an experimental study is carried out on six axial compressors under rotating inlet distortion, aiming to clarify the effects of rotating inlet distortion and reveal the stall mechanism. The result under rotating inlet distortion shows that the rotational speed of distortion strongly affects the stability of the compressor. Within a certain band of distortion speeds, i.e., in the dangerous distortion speed band, the stability margin of the compressor decreases extremely severely. Comparing the results from the six compressors, it is discovered that the left boundary of the dangerous distortion speed bond coincides with the propagation speed of rotating stall, whereas the right boundary is associated with the distortion angle. When introduced rotating inlet distortion, flow separation is prone to occur in the high-load region, which consequently induces stall disturbance. The reason for the varying stability margin with the distortion speed is that the distortion zone at different speeds affects the spatiotemporal evolution of the stall disturbance. Within the dangerous distortion speed bond, the intensified effect of the distortion zone accelerates the evolution of stall disturbance into rotating stall. At the end of this paper, a model is proposed to explain the impact of distortion speed and distortion angle on compressor stall.
On the evaporation dynamics of Ouzo ternary mixture droplets
Authors: Wang Xiaoyu , Ye Xuemin , Yan Yaru , Li Chunxi
Published: February 2025

The evaporation of ternary mixed droplets (TMDs) is a complex multi-physical process involving the evaporation of different components, interactions, and surface phenomena. Understanding and simulating such a process is of great importance for many industrial applications and scientific research. In this study, a theoretical model for the evaporation dynamics of TMDs is developed, and the finite element method is used to simulate the dynamic evaporation of Ouzo TMDs on a heated substrate. The internal flow structure during the evaporation is analyzed, and the unique, spontaneous emulsification phenomenon, known as the “Ouzo effect,” is explored. The influence of substrate heating temperature and initial ethanol concentration on the evaporation characteristics of Ouzo TMDs is also examined. The results show that in the early stages of evaporation, the droplets exhibit a chaotic multi-vortex flow structure. As evaporation progresses, the internal flow becomes predominantly clockwise, while in the later stages, the flow direction reverses to counterclockwise. The highest liquid temperature is observed at the contact line, where ethanol evaporates more rapidly. The Ouzo effect first appears near the contact line and gradually spreads along the bottom of the droplet toward the interior, ultimately reaching the center. Both increasing the substrate heating temperature and the initial ethanol concentration accelerate the evaporation rate of the droplets. Higher substrate heating temperature not only accelerates both the evaporation and emulsification processes but also shortens the duration of the Ouzo effect. In contrast, a higher initial ethanol concentration delays the onset of the Ouzo effect and reduces its duration.
Identification of a central regulator of ginkgolide biosynthesis in
Ginkgo biloba
that integrates jasmonate and light signaling
Authors: Du Jinfa , Zhao Zhen , Jin Lingqi , Huang Lijin , Jin Dian , Zheng Xiaoyan , Wang Qiaolei , Xu Wenbo , Guo Huijun , Xing Xinyue , Alolga Raphael N. , Tran Lam-Son Phan , Herrera-Estrella Luis Rafael , Li Ping , Yin Xiaojian , Lu Xu
Published: February 2025

Ginkgolides are secondary metabolites unique to
Ginkgo biloba
with the potential to prevent and treat cardiovascular and cerebrovascular diseases. Although the biosynthetic pathways of ginkgolides have been partly uncovered, the mechanism regulating their biosynthesis is still largely unknown. Here, using multiomic and genetic analyses, we report the identification of a transcription factor, named ETHYLENE RESPONSE FACTOR ASSOCIATED WITH GINKGOLIDE BIOSYNTHESIS (GbEAG), as a critical regulator of ginkgolide biosynthesis.
GbEAG
is highly expressed in the roots of
G. biloba,
and its expression is significantly induced by methyl jasmonate (MeJA). Ginkgolide content was significantly increased in roots by overexpressing
GbEAG
using a “cut-dip-regeneration” system. GbEAG positively regulates ginkgolide biosynthesis by directly binding to the GCC-boxes in the promoter regions of genes involved in the biosynthesis of ginkgolides, such as
ISOPENTENYL DIPHOSPHATE ISOMERASE
(
GbIDI
) and
CYTOCHROME P450 7005C3
(
GbCYP7005C3
). GbEAG mediates the jasmonic acid (JA)-activated ginkgolide synthesis through its direct interaction with the JASMONATE ZINC-FINGER INFLORESCENCE MERISTEM DOMAIN 3 (GbJAZ3) repressor. Importantly, we also found that the central light-response regulator ELONGATED HYPOCOTYL 5 (GbHY5) mediates light induction of ginkgolide biosynthesis by binding to the G-box in the
GbEAG
promoter. Our findings provide mechanistic insights into the coordinated regulation of ginkgolide biosynthesis via JA and light signals, with GbEAG as a central regulator in
G. biloba,
and shed light on the potential to develop ginkgolide-rich varieties through molecular breeding and gene editing.
Activation-induced thrombospondin-4 works with thrombospondin-1 to build cytotoxic supramolecular attack particles
Authors: Cassioli Chiara , Capitani Nagaja , Staton Claire C. , Schirra Claudia , Finetti Francesca , Onnis Anna , Alawar Nadia , Tu Szu-Min , Lopresti Ludovica , Tatangelo Vanessa , Tangredi Carmela , Valvo Salvatore , Chang Hsin-Fang , Miccoli Annachiara , Compeer Ewoud B. , Nicholls Jemma , Blazar Bruce R. , Marotta Giuseppe , Wood Matthew J. A. , Trentin Livio , Patrussi Laura , Dustin Michael L. , Becherer Ute , Baldari Cosima T.
Published: February 2025

Cytotoxic attack particles released by CTLs and NK cells include diverse phospholipid membrane and glycoprotein encapsulated entities that contribute to target cell killing. Supramolecular attack particles (SMAPs) are one type of particle characterized by a cytotoxic core enriched in granzymes and perforin surrounded by a proteinaceous shell including thrombospondin (TSP)-1. TSP-4 was also detected in bulk analysis of SMAPs released by CTLs; however, it has not been investigated whether TSP-4 contributes to distinct SMAP types or the same SMAP type as TSP-1 and, if in the same type of SMAP, whether TSP-4 and TSP-1 cooperate or compete. Here, we observed that TSP-4 expression increased upon CD8
+
T cell activation while, surprisingly, TSP-1 was down-regulated. Correlative Light and Electron Microscopy and Stimulated Emission Depletion microscopy localized TSP-4 and TSP-1 in SMAP-containing multicore granules. Superresolution dSTORM revealed that TSP-4 and TSP-1 are usually enriched in the same SMAPs while particles with single-positive shells are rare. Retention Using Selective Hooks assays showed that TSP-4 localizes to the lytic granules faster than TSP-1 and promotes its accumulation therein. TSP-4 contributed to direct CTL-mediated killing, as previously shown for TSP-1. TSP-4 and TSP-1 were both required for latent SMAP-mediated cell killing, in which released SMAPs kill targets after removal of the CTLs. Of note, we found that chronic lymphocytic leukemia (CLL) cell culture supernatants suppressed expression of TSP-4 in CTL and latent SMAP-mediated killing. These results identify TSP-4 as a functionally important component of SMAPs and suggest that SMAPs may be targeted for immune suppression by CLL.
Variable transduction of thyroid hormone signaling in structures of the mouse brain
Authors: Sinkó Richárd , Salas-Lucia Federico , Mohácsik Petra , Halmos Emese , Wittmann Gábor , Egri Péter , Bocco Barbara M. L. C. , Batistuzzo Alice , Fonseca Tatiana L. , Fekete Csaba , Bianco Antonio C. , Gereben Balázs
Published: February 2025

L-thyroxine (L-T4) monotherapy is the standard treatment for hypothyroidism, administered daily to normalize TSH levels. Once absorbed, T4 is converted to T3 to alleviate most symptoms. However, this treatment abnormally elevates plasma T4 levels in over 50% of patients. Using L-T4-treated Thyroid Hormone (TH) Action Indicator mice, which express a T3-regulated luciferase (Luc) reporter, we examined whether these T4 elevations disrupt TH signaling. Hypothyroid mice exhibited reduced Luc expression across brain regions, and L-T4 treatment failed to restore T3 signaling uniformly. There was also variability in the activity of type 2 deiodinase (D2), the enzyme that generates most brain T3. Intracerebroventricular T4 administration achieved higher elevation of Luc expression in the mediobasal hypothalamus compared to the cortex, and studies on cultured cortical astrocytes and hypothalamic tanycytes revealed cell-type-specific responses to T4. In tanycytes, exposure to T4 sustained D2 activity, leading to progressive T3 signaling, whereas in astrocytes, T4 exposure triggered a drop in D2 activity, limiting T3 production through a ubiquitin-dependent, self-limiting mechanism. The sustained D2 activity in tanycytes was linked to rapid deubiquitination by USP33, as confirmed using a ubiquitin-specific protease (USP) pan-inhibitor and USP33 knockout mice. In conclusion, the brain’s response to L-T4 treatment is heterogeneous, influenced by cell-specific regulation of D2-mediated T3 production. While cortical astrocytes exhibit limited T3 signaling due to D2 ubiquitination, tanycytes coexpressing USP33 amplify T3 signaling by rescuing ubiquitinated D2 from proteasomal degradation. These findings provide mechanistic insights into the limitations of L-T4 therapy and highlight the need for tailored approaches to managing hypothyroidism.
Impact of
APOE
,
Klotho,
and sex on cognitive decline with aging
Authors: Shibata Kengo , Chen Cheng , Tai Xin You , Manohar Sanjay G. , Husain Masud
Published: February 2025

The effects of apolipoprotein E (
APOE
) and
Klotho
genes, both implicated in aging, on human cognition as a function of sex and age are yet to be definitively established. Here, we showed in the largest cohort studied to date (
N
= 320,861) that
APOE
homozygous ε4 carriers had a greater decline in cognition with aging compared to ε3 carriers (ε3/ε4 and ε3/ε3) as well as smaller hippocampi and amygdala (
N
= 29,510). Critically, sex and age differentially affected the decline in cognition. Younger (40 to 50 y) female homozygous ε4 carriers showed a cognitive advantage over female ε3 carriers, but this advantage was not present in males. By contrast,
Klotho-VS
heterozygosity did not affect cognition or brain volume, regardless of
APOE
genotype, sex, or age. These cognitive trajectories with aging demonstrate clear sex-dependent antagonistic pleiotropy effects of
APOE
ε4, but no effects of
Klotho
genotype on cognition and brain volume.
The creation of new academic knowledge spaces through the repatriated self-translation of foreign-language
texts
Authors: Wang Binhua , Sun Yifeng
Published: February 2025

This article examines the repatriated self-translation of a historical monograph, The Fifteenth Year of
Wan-li, by the migrant Chinese-American historian Ray Huang from his English manuscript 1587, a Year of No
Significance. Through an archival analysis of the process of self-translation and publication, it is shown that the
monograph’s innovative content, style, and perspectives on history studies, as well as its re-contextualisation within the Chinese
context and culture, contributed to the unprecedented popularity of the self-translated monograph in China. Through a comparative
intertextual analysis of the English–Chinese parallel corpus of the monograph, we observe how the self-translator made a
number of non-obligatory shifts and employed distinct strategies to return the monograph from the foreign-language text back to
Chinese. This study provides evidence of the agency and latitude of academic self-translators in interpreting the original work
and in adapting, revising, and rewriting the target text. It also reveals how migrant academics create new knowledge spaces
through implicit translation in their foreign-language texts and (re)create new knowledge spaces through repatriated
self-translation for their native academic community.
Manipulation and trapping of magnetic skyrmions with domain walls in chiral magnetic thin films
Authors: Leask P
Published: February 2025

In this article we use chiral domain walls to manipulate and trap magnetic skyrmion quasi-particles in chiral magnetic materials such as ultrathin Co/Pt films. The magnetic skyrmions can be orientated such that their interaction with domain walls is repulsive, allowing for them to be stored between domain walls. In certain orientations, the skyrmion can be absorbed into the domain wall, forming a domain wall kink. In other orientations, it can absorbed to form a kink-antikink domain wall with zero topological charge. The magnetic skyrmion can even be orientated in such a way that it remains trapped but creates a topological defect-antidefect pair in one of the walls. By altering the phases of one of the chiral domain walls, one can erase or store the magnetic skyrmion as an isolated soliton or as a domain wall skyrmion/antiskyrmion. This adds a valuable asset to an ever growing toolbox of spintronic nano-devices.
Improved CKF Collaborative Positioning Algorithm Between UAVs Based on UWB/IMU
Authors: Lv Yunzhu , Liu Songlin , Dai Jun , Li Jianglong , Liu Yang
Published: February 2025

Addressing the challenges of position information solution among multiple Unmanned Aerial Vehicles (UAVs) and the issue of low relative navigation accuracy, an improved collaborative localization algorithm based on the Cubature Kalman Filter (CKF) is proposed. It utilizes a tightly coupled approach to construct a relative ranging model equipped with Ultra-Wideband (UWB) and Inertial Measurement Unit (IMU) sensors, enabling the correction of self-navigation information. The cosine similarity function is utilized to determine the reliability of the observations, and the observation noise matrix is adaptively adjusted based on the new interest vector from each iteration, thereby refining the positioning trajectory for collaborative navigation. Simulation experiments results demonstrate that the improved CKF collaborative localization algorithm significantly enhances the relative positioning accuracy between UAVs, effectively reduces the maximum relative positioning error, and exhibits strong anti-interference capabilities. It is more suitable for indoor multi-UAV and multi-sensor collaborative localization.
RF-CPO-SVR algorithm for indoor localization based on wifi fingerprints
Authors: Wang Yanchun , Xue Chuanlong , Xia Ying , Sun Shaoye , Liu Mengmeng
Published: February 2025

With the rapid development of wireless communication technology, WiFi indoor positioning has become an important method for achieving indoor localization. Achieving high accuracy in WiFi positioning is a challenging issue. To enhance the accuracy of positioning systems, this paper proposes a WiFi indoor positioning algorithm that uses the random forest (RF) algorithm for access point (AP) selection and the Crested Porcupine Optimizer (CPO) algorithm to optimize support vector regression (SVR), referred to as RF-CPO-SVR. The RF algorithm selects APs by evaluating the feature importance of each AP, reducing the negative impact of redundant and unstable APs on the performance of the positioning system. After AP selection, the CPO algorithm is used to optimize the hyperparameters of SVR, further improving the system’s performance. Comprehensive tests of the proposed RF-CPO-SVR algorithm were conducted on public datasets, and the results show that 90% of the positioning accuracy is within 4 m, with an average positioning error of 2.1082 m. Experimental results demonstrate that the RF-CPO-SVR algorithm outperforms traditional positioning methods and existing classical optimization algorithms, improving positioning accuracy by 23.5%, 27.4%, and 24.7% compared to particle swarm optimization-SVR, GA-SVR, and K nearest neighbors, respectively.
Comparative analysis of Y2O3 and Al2O3 interfacial layers in modulating the electrical properties of ZrO2 and HfO2 on Ge
Authors: Lee Woohui , Shin Hyungchul , Chae Jinwoong , Lee Jehoon , Eom Deokjoon , Oh Joohee , Kim Hyoungsub
Published: February 2025

This study compares the effects of ultrathin Y2O3 and Al2O3 interfacial layers on the electrical properties of ZrO2 and HfO2 dielectrics deposited on Ge substrates, specifically examining the ZrO2/Y2O3, ZrO2/Al2O3, HfO2/Y2O3, and HfO2/Al2O3 stacked structures. Reductions in both interface trap density (D
it) and leakage current were observed after five cycles of the atomic layer deposition (ALD) process for Y2O3 and Al2O3 interfacial layers. Compared with Y2O3, the Al2O3 interfacial layer was more effective in reducing the leakage current and decreasing the effective bulk trap density (N
trap). However, this also leads to an increase in the capacitance-equivalent oxide thickness, which could be a potential drawback. The observed electrical properties are closely linked to the distinct interfacial reactions of Y2O3 and Al2O3 with Ge during ALD, resulting in similar reductions in D
it. However, the formation of a thick Al2O3 interfacial layer was more efficient in suppressing Ge out-diffusion than Y2O3, which contributed to the reduction in both the leakage current and N
trap.
Theoretical method and experimental verification for solving two/three component phononic crystals based on comsol partial differential equation module
Authors: Qian Denghui , Liu Zhenqiao , Zhang Shengke , He Feiyang
Published: February 2025

In order to reduce the low frequency vibration and noise of ships, the phononic crystal structure is used to control the vibration and noise of ships. Based on three-dimensional spatial elastic wave theory and plane wave expansion method, combined with the differential equation module of finite element software, the band structure and transport characteristics of phononic crystal structure can be accurately solved. The correctness and feasibility of this method are verified by comparison with the simulation results of solid mechanics module of finite element software, which provides a new idea for solving phononic crystal structure. It lays a solid foundation for further study of phononic crystal structure. At the same time, this paper studies a new phononic crystal sandwich plate structure, which is applied to the vibration and noise reduction of ships. The theoretical method and experiment are used to study the structure, which proves that the structure has good vibration and noise reduction performance, and further explains the correctness and feasibility of the theoretical method. Based on this calculation method, it can be used to study the effect of the geometrical parameters and material parameters of phononic crystal structure on the band gap. By adjusting these parameters reasonably, the ship can achieve a good effect of vibration and noise reduction.
Acoustic metasurface constructed by Helmholtz-like resonators with embedded necks of gradient cross-section
Authors: Chen Jung-San , Wang Wei-Chun , Tsai I-Yu , Liao Yu-Sheng , Luo Xiang-Cheng
Published: February 2025

This study proposes a compact acoustic metasurface consisting of Helmholtz-like resonators arranged in series/parallel. Unlike the traditional design equipped with uniform necks, the proposed necks possess gradient cross-section in a 2D plane. The geometric parameters of the present structure are designed and optimized by using a particle swarm optimization algorithm (PSO). This structure exhibits excellent sound absorption below 200 Hz with a deep subwavelength thickness. Adjusting the neck length is effective in altering the absorption peak frequency. A structure with resonators in series yields approximately 80%–90% absorption at 129 Hz, while the one with resonators in parallel yields almost the same absorption coefficient, but the absorption peak frequency is increased by 15%. Theoretical and numerical finite-element-method predictions match well with experimental results.
Prolongation structures of the super mixed derivative nonlinear Schrödinger equation
Authors: Su Huajie , Yu Yuanyuan , Guo Jiafeng , Yan Zhaowen
Published: February 2025

In this paper, we investigate the super mixed derivative nonlinear Schrödinger (super MDNLS) equation by means of fermionic prolongation structure approach. Based upon representations of the prolongation algebra, we present the Lax representation and the Bäcklund transformation of the super MDNLS equation.
Soliton, breather and double-layer structures formation of ion acoustic waves in weakly magnetized non-thermal plasmas
Authors: Majee Debakinandan , Biswas Akash
Published: February 2025

The dynamics of the obliquely propagating weakly nonlinear ion acoustic waves are investigated in a collisionless weakly magnetized plasmas in the context of the Cairns distributed non-thermal electrons. A three-dimensional Korteweg de-Vries (KdV) equation, colloquially known as the Laedke-Spatschek (LS) equation, has been shown to describe the dynamics of the nonlinear wave. Analytical solutions depending on the physical parameters predict solitary, periodic and breather like structures. Interestingly, at a critical value of the non-thermal parameter, the dynamics is found to be governed by a modified LS equation which is conditionally Painlevé integrable. Exact analytical solution with the help of Bäcklund transformation reveals that the modified LS equation supports a double-layer, sawtooth-like periodic and breather-like structures. The results are discussed in the context of astrophysical observations in the auroral region.
Investigation on the temporal evolution of the Druyvesteyn distribution function between sheath and presheath region in material processing plasmas
Authors: Tiwari Pawan K , Kumar Ravindra , Lee Yeon Soo
Published: February 2025

The energy distribution of particles in a gaseous system is primarily understood by the Maxwell–Boltzmann distribution function. However, in the case of partially ionized discharge plasmas which provide a unique attribute in the event of material processing, a Druyvesteyn distribution function rather than a Maxwellian function becomes a key contributor in understanding the electron energy distribution functions. Alteration in the distribution function from Maxwellian to Druyvesteyn is evident in the presence of external forces on the plasma particles, especially when electrons are heated by the electric field. In the present work, we study the time evolution of the Druyvesteyn distribution function in the presence of the external electric field. We found a rapid departure in nature from its equilibrium form and observed that the effusion process of electrons in the sheath regions can be controlled by applying the external electric field. The longitudinal current density increases with time, which is contrary to the case of the transverse current density. It indicates that the unidirectional flow reaching saturation with time is a collimated yield of the electrons. Also, electron energy reaches saturation and the distribution function shrinks with time, which indicates a monochromatic (monoenergetic) yield of electrons. Moreover, collimation and monochromatism can be controlled by the external electric field. Such control is quite desirable in material processing. On the application side, the methodology can be harnessed to generate plasma plume which has a potential application in the creation of biomedical plasma apparatuses.
Wide binary evaporation by dark solitons: implications from the GAIA catalog
Authors: Qiu Qiming , Gao Yu , Tian Haijun , Wang Kechen , Wang Zihang , Yang Xiangming
Published: February 2025

An analytic calculation is given for binary star evaporation under the tidal perturbation
from randomly distributed, spatially extended dark objects. In particular, the Milky Way's wide
binary star population is susceptible to such disruption from dark matter solitons of comparable
and larger sizes. We identify high-probability `halo-like' wide binaries in GAIA EDR3 with
separations larger than 0.1 parsec. Survival of the farthest-separated candidates will provide a
novel gravitational probe to dark matter in the form of solitons. In the case of dilute axion-like
boson stars, the observational sensitivity extends into the axion mass range ma
∼
10-17 -10-15eV.
Outline on selected properties of densified veneers and the produced plywood
Authors: Manea Emilia-Adela Salca , Bekhta Pavlo
Published: February 2025

Wood densification is one of the methods used to modify its properties to create a material with an increased density and implicitly improved properties. Generally, densification is applied to low-density and fast-growing wood species. Lower pressures and temperatures are applied for shorter time spans to densify veneers when compared to solid wood. Along with their increased strength, hardness, and durability, densified veneers present an attractive dark colour, a smooth surface, improved gloss, and higher thermal conductivity. There is a special interest in densified veneers for plywood production. These products present increased dimensional stability, higher strength properties, and a pleasant appearance having various applications. The present paper revises selected properties of densified veneers made of black alder wood species and the mechanical properties of plywood when produced from them.
The influence of impact loading on microstructure and texture of copper single crystals of nominally stable orientations
Authors: Puchlerska Sandra , Paul Henryk , Mania Izabela
Published: February 2025

In this study, single-crystal samples of pure copper with stable orientations – Br (110)[112] and G(110)[001] – were impact-loaded in a channel die, with the punch driven by explosive energy, to achieve a strain rate of 4 × 105 s−1. Microstructural characterization was conducted on samples deformed up to 60%, using optical microscopy and SEM across a wide range of scales. Texture evolution was analysed through X-ray diffraction and SEM/EBSD. Both orientations exhibited highly unstable behaviour due to deformation twinning and the development of plastic flow instabilities in the form of deformation bands. In G(110)[001]-oriented crystals, twinning occurred on two planes, while in Br(1-10)[112]-oriented crystals, twinning occurred on all four {111} planes, which are highly favoured for slip activity during deformation. The formation of plastic flow instabilities in narrow regions resulted from the dominance of a single slip system in selected regions of the Br-oriented crystal, or a pair of highly favoured slip systems in the G orientation.
Inelastic buckling of reinforcing bars - constitutive model for monotonic compression
Authors: Korentz J
Published: February 2025

Reinforced concrete structures can be subjected to plastic deformation as a result of seismic actions or exceptional loads. In this case, inelastic buckling of the compressed reinforcement bars may occur. According to the provisions of the EC2 standard, bar buckling is not taken into account in the ultimate limit state check; the same physical models are used for both tension and compression bars. The models of compression bars known in the literature, which take into account inelastic buckling, reproduce their behaviour in a limited range of mechanical properties of steel or require a large amount of data. This paper proposes a new, simple, four-linear model of the behaviour of compression reinforcing bars taking into account inelastic buckling. The proposed model shows satisfactory agreement with experimental results. It can be applied to model the behaviour of steel bars with different mechanical properties in the analysis of the plastic hinge behaviour of reinforced concrete elements.
Evaluation of Theories and Methodologies: Relativistic Physics vs. the Dynamic Universe — With Remarks from Physics and Reality 2024 and Cosmology on Small Scales 2024 Conferences
Authors: Styrman Avril
Published: February 2025

In the classical ideal, a physical theory provides understandable dynamic explanations and yields novel predictions of phenomena. Relativistic Physics (RP), namely the special and general theories of relativity and relativistic cosmology, does not meet the classical ideal. This discrepancy has been addressed by transforming the classical ideal into a ‘relativistic methodology’, where it is accepted that nature is not fully understandable, predictions are prioritized over dynamic explanations, new phenomena may be accommodated in an orderly fashion with the aid of additional hypotheses, and anomalous data may be disregarded. Relativistic methodology and the enduring confidence in RP stem from tradition, where physicists who have learned to conceptualize reality through RP see it as the only alternative. The greatest 20th-century philosophers of science —Karl Popper, Thomas Kuhn, Imre Lakatos and Paul Feyerabend— have taught us that to fully understand a theory’s weaknesses, it must be juxtaposed with an alternate theory, and that its replacement requires a superior theory. Here, RP is confronted with Tuomo Suntola’s Dynamic Universe (DU). Suntola claims that DU matches or surpasses RP’s predictive accuracy for several central phenomena from the terrestrial to the largest cosmological scales, while adhering to the classical ideal and cohering with quantum mechanics. If this claim withstands scrutiny, DU deserves further attention from physicists, philosophers and funding institutions.
A Framework for Free Will within a Quantum Universe
Authors: Pulga Alessandra
Published: February 2025

Advancements in neuroscience make the question of free will more pressing. Between physicalist positions, which largely deny free will, and libertarian views, which reject determinism, quantum mechanics initially appeared to offer a middle ground. Even though it was thought to depict a probabilistic reality allowing some degree of freedom in choices, quantum mechanics remains deterministic, albeit with stochastic results. This paper proposes an alternative where quantum mechanics still supports free will as the possibility to do otherwise within a physicalist framework. Through the manyworlds interpretation, I show how the principle of alternative possibilities can be maintained, even when both our decision-making processes and the external world follow physical laws.
The application and development prospects of extracellular vesicles in oral administration
Authors: Li Weiqun , Dong Ming-Jie , Shi Zhaoqing , Dai Haibing , Lu Shanming , Wu Huibin , Zhang Fan , Lu Guihong , Yu Jianbo
Published: February 2025

Extracellular vesicles (EVs) are nanoscale phospholipid-based particles secreted by cells and are essential mediators responsible for intercellular signal communication. The rapid development of EV nanotechnology has brought unprecedented opportunities for nanomedicine. Among various administration methods, oral administration is the most convenient and simplest. However, most drugs (peptides, small molecule drugs, nucleic acids, and therapeutic proteins) greatly reduce their oral bioavailability due to the harsh gastrointestinal environment. Notably, some EVs have been shown to cross biological barriers, including the gastrointestinal tract. The distinctive biological properties of EVs make them a promising natural carrier for oral drug delivery. This review introduces the characteristics of EVs, covering their classification, production methods, and therapeutic efficacy in oral administration. Additionally, we explore the potential roles of EVs in disease prevention and treatment, as well as their future prospects in pharmaceutical applications. This comprehensive overview aims to provide insights into the application of EVs in oral drug delivery, highlighting their advantages, current progress, and the challenges that need to be overcome for successful clinical translation.
Three-dimensional cell culture-derived extracellular vesicles loaded alginate/hyaluronic acid composite scaffold as an optimal therapy for cartilage defect regeneration
Authors: Zhang Wanting , Li Shuyi , Peng Yingying , Deng Zhujie , Li Quanjiang , Tian Rui , Kuang Xiubin , Kang Yuyi , Sun Ronghui , Huang Chen , Yuan Zhengqiang
Published: February 2025

Osteoarthritis (OA) is a chronic musculoskeletal disease characterized by joint inflammation and progressive degeneration of articular cartilage. Currently a definitive cure for OA remains to be a challenge due to the very low self-repair capacity of cartilage, thus development of more effective therapies is needed for cartilage repair. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have shown great potential as therapeutic agents for stimulating regeneration of articular cartilage. However, a standardized protocol is still lacking for manufacturing of highly active EVs for clinical applications. This study aimed to investigate the efficient production of highly active EVs by 3-dimensional (3D) MSC culture, verify the reparative efficacy of EVs on cartilage defect and elucidate the repair mechanisms. Umbilical cord MSCs were embedded in alginate to form MSC spheroids for 3D culture in human platelet lysate (hPL)-containing medium, which produced 3D culture-derived EVs (3D-EVs) with a significantly improved yield. The 3D-EVs expressed higher level of VEGF, and appeared superior to two-dimensional (2D) monolayer MSC culture-derived EVs (2D-EVs) to improve migration and proliferation in MSCs and inflammatory chondrocytes, and to suppress expression of cartilage-degrading factors. Importantly, the 3D-EVs and sodium alginate (SA)-hyaluronic acid (HA) composite hydrogel (3D-EVs/SA-HA) demonstrated significantly improved therapeutic efficacy than 2D-EVs/SA-HA hydrogel for repair of cartilage defect in vivo. The underlying mechanisms are associated with the concomitant upregulation of type II collagen and cartilage synthesis and downregulation of MMP13 in cartilage tissues. Collectively, these data showed that highly active MSC EVs could be efficiently manufactured by 3D cell culture with hPL-containing medium, and these EVs were superior to 2D-EVs for the repair of articular cartilage defect.
Enabling boosting abrasion resistance of titanium alloy matrix via B4C particles doping micro arc oxidation coating strategy
Authors: Chen Xiaowen , Luo Han , Zhang Defen , Tang Song , Luo Bin , Yang Junwei , Xie Wanlin
Published: February 2025

Titanium alloy is recognized as the future metal due to its remarkable advantages, including high strength, lightweight properties, and corrosion resistance. Meanwhile, there are a series of technical challenges hindering its development, such as poor abrasion resistance. Herein, we propose a direct strategy by combining micro arc oxidation (MAO) technology with B4C particles doping that can effectively ameliorate the contact mechanics at the interface and regulate the microporous structure of the MAO coating. Exhilaratingly, compared to the titanium alloy and undoped samples, the modified B4C-doped alloy (B0.9) exhibited high hardness of 706.2 HV (increased by 121.9% and 15.8%, respectively) and low friction coefficient of 0.3435 (ameliorated by 40.6% and 39.6%, respectively). Utilizing in x-ray diffraction, scanning electron microscopy, and Image Pro Plus analysis, we found that B0.9 exhibited lower surface porosity and average pore size (8.7% and 3.0 μm, respectively), which are attributed to the regulation of the microporous structure. Specifically, B4C particles are successfully incorporated into the MAO coating by mechanical stirring and electrophoresis, filling the surface micropores and resulting in a denser and more uniform coating. This study emphasizes the compatibility between B4C doping and MAO technology, which effectively provides guidance for the inadequate abrasion resistance of titanium alloy.
Enhancement of tribological properties by fabricating gradient structure and MoS2 coating on the surface of 06Cr19Ni9 stainless steel
Authors: Li Dongwei , Li Jiahao , Huang Qisheng , Liu Zixi , Chen Mingchao , Xiao Jinrui
Published: February 2025

Stainless steel is extensively used in civil engineering and mechanical industries due to its superior corrosion resistance and mechanical performance. Nevertheless, its surface is prone to wear, which can compromise component functionality and introduce safety concerns. The present study developed a composite structure consisting of a gradient microstructure layer combined with a pure MoS2 coating on the surface of 06Cr19Ni9 stainless steel. The fabrication process involved ultrasonic shot peening using α-Al2O3 particles, followed by thermal spraying. Fretting friction and wear using the ball-on-disc method demonstrated a notable improvement in tribological performance. The composite structure achieved a remarkably low friction coefficient of 0.16 under a normal load of 15 N representing a 74.19% reduction compared to a mechanically polished sample. However, when subjected to a higher normal load of 50 N, the friction coefficient increased significantly. Despite a relatively higher wear rate, the composite structure effectively safeguarded the metal matrix from substantial wear during testing. The enhanced tribological properties were primarily attributed to the synergistic interaction between the gradient microstructure layer and the MoS2 coating. These findings underscore the potential of this composite structure to significantly improve the wear resistance and extend the operational life of 06Cr19Ni9 stainless steel.
Magnetically shielded high-resolution visual stimulation for OPM-MEG applications
Authors: Anders P , Brickwedde M , Voigt J , Grent-‘t-Jong T , Krüger P , Haueisen J , Uhlhaas P J , Sander T
Published: February 2025

Many magnetoencephalography (MEG) experiments require visual stimulation (VS) inside a magnetically shielded room (MSR). For conventional MEG utilizing superconducting quantum interference devices (SQUIDs), the participant’s head must stay within the semi-spherical surface of a cryogenic storage Dewar. This design allows to have many SQUID sensors as close as possible to the head in order to achieve good signal quality. Because Dewars have very restricted mobility, VS is usually realized using a projector outside of the MSR, some optical elements and a back-projection screen in the line of sight of the participant.

Recently, the feasibility of MEG using optically pumped magnetometers (OPMs) was demonstrated. These sensors can be attached directly to the head because they operate near room temperature. OPM-MEG therefore offers more experimental freedom including different postures, movements or hyperscanning, creating the need for a more flexible kind of VS setup.

In this paper, we present a compact, high-resolution VS setup which is enclosed by a portable magnetic shield with an opening for the projection. The VS setup is based on a single-board computer which acts as experiment control device to create visual stimuli, process inputs, log participant activity and set off trigger signals. This setup supports the new possibilities of OPM-MEG and can be easily installed into any MSR. We investigate if the shielded VS inside the MSR generates distortion signals above the noise floor of the OPMs. We also show that visual cortex activity can be evoked with our setup and recorded with a custom-made OPM-MEG cap. By applying two well-established visual stimulation paradigms, we demonstrate the ability of our setup to elicit brain activity in different frequency ranges.
All-printed WO3 films on an Ag-interdigitated electrode derived from aqueous screen-printable inks for room-temperature ammonia gas detection
Authors: Praveen Lakkimsetti Lakshmi , Singh Nitesh Pratap , Vardhan Robbi Vivek , Mandal Saumen
Published: February 2025

In this work, all-printed tungsten oxide (WO3) sensors were fabricated from nanoparticle-based screen-printable inks, where the WO3 nanopowders were hydrothermally synthesized with various HCl concentrations to give enhanced room-temperature detection of ammonia (NH3) gas. The monoclinic phase of WC powders (calcined WO3) with square nanoplate-like morphology and porosities was identified from x-ray diffraction, field-emission scanning electron microscopy and Brunauer–Emmett–Teller surface area analysis. The silver precursor ink-derived interdigitated electrodes were found to be crystalline with an average finger width and Ag film thickness of 1 ± 0.4 mm and 3.8 ± 0.5 µm, respectively. The formulated WO3 inks with hydroxyethyl cellulose showed a thixotropic fluid-like behavior and exhibited a viscosity of ∼9 × 104 mPa s, which is a key requirement for screen printing. Rheological study of the formulated WC inks revealed a thixotropic nature, with all WC inks showing a viscosity of 85 ± 3 Pa s and a recovery rate of 80% in the recovery stage. This work explains the role of pH in hydrothermally synthesis of WO3 by correlating the gas-sensing characteristics of the screen-printed sensors fabricated from formulated inks, where the WC-15 gas sensor showed a maximum gas response of ∼340 towards 100 ppm of NH3 gas. This facile and cost-effective method for fabricating chemiresistive gas sensors could pave the way for the development of flexible and printable devices for ppb-level detection of NH3 gas and its monitoring.