bluuebunny/crossref_metadata_2025 huggingface dataset:
Active polar ring polymer in shear flow—An analytical study
Authors: Winkler Roland G. , Singh Sunil P.
Published: August 2024

We theoretically study the conformational and dynamical properties of semiflexible active polar ring polymers under linear shear flow. A ring is described as a continuous semiflexible Gaussian polymer with a tangential active force of a constant density along its contour. The linear but non-Hermitian equation of motion is solved using an eigenfunction expansion, which yields activity-independent, but shear-rate-dependent, relaxation times and activity-dependent frequencies. As a consequence, the ring’s stationary-state properties are independent of activity, and its conformations and rheological properties are equal to those of a passive ring under shear. The presence of characteristic time scales by relaxation and the activity-dependent frequencies give rise to a particular dynamical behavior. A tank-treading-like motion emerges for long relaxation times and high activities, specifically for stiff rings. In the case of very flexible polymers, the relaxation behavior dominates over activity contributions suppressing tank-treading. Shear strongly affects the crossover from a tank-treading to a relaxation-dominated dynamics, and the ring polymer exhibits tumbling motion at high shear rates. This is reflected in the tumbling frequency, which displays two shear-rate dependent regimes, with an activity-dependent plateau at low shear rates followed by a power-law regime with increasing tumbling frequency for high shear rates.
Si1−x−yGeySnx alloy formation by Sn ion implantation and flash lamp annealing
Authors: Steuer O. , Michailow M. , Hübner R. , Pyszniak K. , Turek M. , Kentsch U. , Ganss F. , Khan M. M. , Rebohle L. , Zhou S. , Knoch J. , Helm M. , Cuniberti G. , Georgiev Y. M. , Prucnal S.
Published: August 2024

For many years, Si1−yGey alloys have been applied in the semiconductor industry due to the ability to adjust the performance of Si-based nanoelectronic devices. Following this alloying approach of group-IV semiconductors, adding tin (Sn) into the alloy appears as the obvious next step, which leads to additional possibilities for tailoring the material properties. Adding Sn enables effective bandgap and strain engineering and can improve the carrier mobilities, which makes Si1−x−yGeySnx alloys promising candidates for future opto- and nanoelectronics applications. The bottom-up approach for epitaxial growth of Si1−x−yGeySnx, e.g., by chemical vapor deposition and molecular beam epitaxy, allows tuning the material properties in the growth direction only; the realization of local material modifications to generate lateral heterostructures with such a bottom-up approach is extremely elaborate, since it would require the use of lithography, etching, and either selective epitaxy or epitaxy and chemical–mechanical polishing, giving rise to interface issues, non-planar substrates, etc. This article shows the possibility of fabricating Si1−x−yGeySnx alloys by Sn ion beam implantation into Si1−yGey layers followed by millisecond-range flash lamp annealing (FLA). The materials are investigated by Rutherford backscattering spectrometry, micro-Raman spectroscopy, x-ray diffraction, and transmission electron microscopy. The fabrication approach was adapted to ultra-thin Si1−yGey layers on silicon-on-insulator substrates. The results show the fabrication of single-crystalline Si1−x−yGeySnx with up to 2.3 at. % incorporated Sn without any indication of Sn segregation after recrystallization via FLA. Finally, we exhibit the possibility of implanting Sn locally in ultra-thin Si1−yGey films by masking unstructured regions on the chip, thus demonstrating the realization of vertical as well as lateral Si1−x−yGeySnx heterostructures by Sn ion implantation and flash lamp annealing.
The nonresonant sum-frequency generation response: The not-so-silent partner
Authors: Patterson James E.
Published: August 2024

Vibrational sum-frequency generation (VSFG) has become a powerful tool for investigating the molecular structure of surfaces and interfaces. One aspect of the technique that has been overlooked is the source and nature of the nonresonant contribution to the measured signal. If not properly accounted for, interaction between the resonant and nonresonant responses can lead to misinterpretation of the resonant signals. The nonresonant response itself also carries important information about the system under study. This Perspective reviews some of the experimental and post-processing techniques that have been developed to isolate the nonresonant response. The focus of such approaches has generally been on the resonant signal, meaning more can be done to learn about the nonresonant response. Some examples of information carried by the nonresonant response are also presented, again showing that there is more to do to understand this signal. The nonresonant sum-frequency generation response is an important component of VSFG measurement, and the VSFG community needs to learn to better understand what it is telling us about our samples.
First-principles investigation of pressure-induced structural, electronic, and thermoelectric properties in CoSb3−xAx compounds (A = Ge, Se, Te)
Authors: Mamani Gonzalo Fredy , Ramirez Rivera Victor José , Jeomar Piotrowski Maurício , Mamani Flores Efracio
Published: August 2024

The enhancement of thermoelectric properties in CoSb3 through atom substitution and hydrostatic pressure application is a promising avenue. Herein, we conducted a comprehensive theoretical investigation into the structural, electronic, and thermoelectric characteristics of CoSb3−xAx (A = Ge, Se, Te; x = 0.125, 0.250) using density functional theory coupled with Boltzmann transport theory. By subjecting the system to pressures ranging from 0 to 20 GPa and substituting Sb atoms, we evaluated the enthalpy of formation to predict stability, with CoSb2.875Te0.125 exhibiting superior stability under 20 GPa. The bandgap of doped compounds is direct, ranging from 0.33 to 0.56 eV along the Γ point, and was calculated to elucidate electronic properties. Additionally, employing the Slack model, we computed lattice thermal conductivity based on elastic constants to provide a comprehensive analysis of thermoelectric efficiency. Remarkably, our study not only highlights the effect of hydrostatic pressure on structural and electronic properties but also reveals a beneficial impact on increasing ZT values to 2.77 for CoSb2.750Ge0.250 at 800 K and 20 GPa, indicating predominantly p-type behavior.
Spatial variability of mineral surface area and carbon sequestration potential at the farm scale – a case study
Authors: McNally Sam , Sharp Joanna , Jaksons Peter , Tregurtha Craig , Beare Mike , White Robyn
Published: August 2024

Context The ability of soils to contribute to greenhouse gas mitigation requires the stock of carbon to be increased in the long term. Studies have demonstrated the potential of soils to increase in carbon at global to regional scales, with soil mineral surface area a key factor to this potential. However, there is limited knowledge on the distribution of mineral surface area and whether the distribution of soil carbon sequestration potential varies at the farm scale. Aims The aim of this study was to evaluate the spatial variability in mineral surface area and sequestration potential of SOC at a farm scale. Methods We used a case study farm to apply existing published methodology and assess the spatial distribution of the mineral surface area, the maximum amount of stable carbon that a soil could hold, and the subsequent potential for soil carbon sequestration at the farm scale. A total of 200 samples were collected across the farm using a balance accepted sampling design prior to analysis for total carbon, mineral surface area, and sequestration potential. Key results Despite being in a localised area, the farm demonstrated that the distributions of mineral surface area and total carbon were related to variation in the underlying soil type. When data were examined spatially, there were areas within the farm that had greater potential to stabilise more carbon and also regions where there were greater carbon stocks. Conclusions The spatial distribution of SOC, mineral surface area, and potential to increase MAOC was well represented by the spatial distribution of soil type within a farm. This case study demonstrated areas within the farm that had potential to increase the MAOC fraction. Implications This case study offers an approach that would give farmers and land managers knowledge to improve the understanding of the carbon dynamics across their farm and to identify areas that have greater potential to contribute to greenhouse gas mitigation and the areas that would be more susceptible to soil carbon loss. Using this approach could allow targeted management practices to be applied to specific regions on-farm to either increase soil carbon or protect existing stocks.
Demography and environment modulate the effects of genetic diversity on extinction risk in a butterfly metapopulation
Authors: DiLeo Michelle F. , Nair Abhilash , Kardos Marty , Husby Arild , Saastamoinen Marjo
Published: August 2024

Linking genetic diversity to extinction is a common goal in genomic studies. Recently, a debate has arisen regarding the importance of genetic variation in conservation as some studies have failed to find associations between genome-wide genetic diversity and extinction risk. However, only rarely are genetic diversity and fitness measured together in the wild, and typically demographic history and environment are ignored. It is therefore difficult to infer whether a lack of an association is real or obscured by confounding factors. To address these shortcomings, we analyzed genetic data from 7,501 individuals with extinction data from 279 meadows and mortality of 1,742 larval nests in a butterfly metapopulation. We found a strong negative association between genetic diversity and extinction when considering only heterozygosity in models. However, this association disappeared when accounting for ecological covariates, suggesting a confounding between demography and genetics and a more complex role for heterozygosity in extinction risk. Modeling interactions between heterozygosity and demographic variables revealed that associations between extinction and heterozygosity were context-dependent. For example, extinction declined with increasing heterozygosity in large, but not currently small populations, although negative associations between heterozygosity, extinction, and mortality were detected in small populations with a recent history of decline. We conclude that low genetic diversity is an important predictor of extinction, predicting >25% increase in extinction beyond ecological factors in certain contexts. These results highlight that inferences about the importance of genetic diversity for population viability should not rely on genomic data alone but require investments in obtaining demographic and environmental data from natural populations.
m
6
A modification plays an integral role in mRNA stability and translation during pattern-triggered immunity
Authors: Chen Tianyuan , Greene George H. , Motley Jonathan , Mwimba Musoki , Luo Guan-Zheng , Xu Guoyong , Karapetyan Sargis , Xiang Yezi , Liu Chang , He Chuan , Dong Xinnian
Published: August 2024

Plants employ distinct mechanisms to respond to environmental changes. Modification of mRNA by
N
 6
-methyladenosine (m
6
A), known to affect the fate of mRNA, may be one such mechanism to reprogram mRNA processing and translatability upon stress. However, it is difficult to distinguish a direct role from a pleiotropic effect for this modification due to its prevalence in RNA. Through characterization of the transient knockdown-mutants of m
6
A writer components and mutants of specific m
6
A readers, we demonstrate the essential role that m
6
A plays in basal resistance and pattern-triggered immunity (PTI). A global m
6
A profiling of mock and PTI-induced
Arabidopsis
plants as well as formaldehyde fixation and cross-linking immunoprecipitation-sequencing of the m
6
A reader, EVOLUTIONARILY CONSERVED C-TERMINAL REGION2 (ECT2) showed that while dynamic changes in m
6
A modification and binding by ECT2 were detected upon PTI induction, most of the m
6
A sites and their association with ECT2 remained static. Interestingly, RNA degradation assay identified a dual role of m
6
A in stabilizing the overall transcriptome while facilitating rapid turnover of immune-induced mRNAs during PTI. Moreover, polysome profiling showed that m
6
A enhances immune-associated translation by binding to the ECT2/3/4 readers. We propose that m
6
A plays a positive role in plant immunity by destabilizing defense mRNAs while enhancing their translation efficiency to create a transient surge in the production of defense proteins.
Honorifics in child-directed speech
Authors: Hildebrandt Gwendolyn
Published: August 2024

How are honorifics, which are socially meaningful and socially conditioned, acquired, when their appearance in
child-directed speech cannot replicate their use in adult-directed speech? In this paper, we conduct corpus and experimental
studies aimed at characterizing the use of honorifics in child-directed speech in Korean. We find that the addressee honorific
-yo is present at notable rates in child-directed speech, although the use of -yo in
child-directed utterances is rated less natural than its absence. We further find that while -yo is given lower
ratings for the presence of relevant social meanings when in child-directed speech compared to adult-directed speech, the use of
-yo in child-directed speech is still significantly associated with these meanings. This suggests that while
the presence of honorifics in child-directed speech is somewhat unexpected, such uses of honorifics nonetheless carry relevant
information about the social meaning of honorifics.
Judges’ reformulations in judicial interpretation in Chinese judgments
Authors: Zhang Liping , Zhang Tingting
Published: August 2024

In hybrid legal contexts in China, judges’ speech acts of reformulating rules serve to demonstrate their
ideological and linguistic preferences in law enforcement. A comparative analysis of judges’ reformulations in judgments in the
traditional (imperial) and contemporary periods in this study discloses a disparity in their speech style over time. Though judges
in the two periods both navigate between the ethical discourse and the legal discourse in the negotiation of meaning in law,
traditional judges are found to have reformulated rules from various sources, particularly those of Confucian classics, acting as more
of a constructive legal interpreter. In contrast, contemporary judges tend to reformulate rules of the codified law in a more
monologic style, thereby displaying greater respect for the autonomy of law in their reformulations. These differences are
interpreted from a socio-cultural standpoint.
Factors Influencing Patient Participation in Inpatient Forensic Psychiatric Care – A Mixed-Method Systematic Review
Authors: Vidaurrazaga Aras Valentina , Alexiou Eirini , Nilsson Thomas , Wolf Axel , Olausson Sepideh
Published: August 2024

In this systematic review, we aimed to identify facilitating or hindering factors for patient participation in inpatient forensic psychiatric care. Ten studies, qualitative ( n = 8), quantitative ( n = 1), and mixed method ( n = 1), were included. Findings were categorized using the European standard for minimum requirements for patient involvement in health care. We identified a supportive care relationship as an essential prerequisite for participation. This includes ensuring that patients feel trust, included in discussions, and seen as a person, beyond the index crime but with an understanding for their psychiatric illness. Patients’ transition phases through their illness and the forensic psychiatric care system initially appeared to negatively influence patient participation. However, as they approached their release from forensic psychiatric care, a positive shift in their willingness to participate in their care became evident. Factors such as stigmatization, safeguarding one’s own security, and the coercive forensic psychiatric care environment, were identified as factors significantly hindering patient participation. Moreover, patients perceived participation in care planning as confusing, as they felt excluded from influencing any care-related decisions. Staff, in contrast, were restrictive with information regarding patient care, which had additional negative effects on patients’ understanding of their situation. We conclude that future research is needed to examine clinical routines and strategies that may improve patient participation. Furthermore, more quantitative research is needed to examine the challenges for this specific patient population and environment. Future interventions should focus on improving the quality of relationships, information-sharing, and patient involvement in key elements of forensic psychiatric care.
AMPK activation induces RALDH+ tolerogenic dendritic cells by rewiring glucose and lipid metabolism
Authors: Brombacher Eline C. , Patente Thiago A. , van der Ham Alwin J. , Moll Tijmen J.A. , Otto Frank , Verheijen Fenne W.M. , Zaal Esther A. , de Ru Arnoud H. , Tjokrodirijo Rayman T.N. , Berkers Celia R. , van Veelen Peter A. , Guigas Bruno , Everts Bart
Published: August 2024

Dendritic cell (DC) activation and function are underpinned by profound changes in cellular metabolism. Several studies indicate that the ability of DCs to promote tolerance is dependent on catabolic metabolism. Yet the contribution of AMP-activated kinase (AMPK), a central energy sensor promoting catabolism, to DC tolerogenicity remains unknown. Here, we show that AMPK activation renders human monocyte-derived DCs tolerogenic as evidenced by an enhanced ability to drive differentiation of regulatory T cells, a process dependent on increased RALDH activity. This is accompanied by several metabolic changes, including increased breakdown of glycerophospholipids, enhanced mitochondrial fission–dependent fatty acid oxidation, and upregulated glucose catabolism. This metabolic rewiring is functionally important as we found interference with these metabolic processes to reduce to various degrees AMPK-induced RALDH activity as well as the tolerogenic capacity of moDCs. Altogether, our findings reveal a key role for AMPK signaling in shaping DC tolerogenicity and suggest AMPK as a target to direct DC-driven tolerogenic responses in therapeutic settings.
Gate Tunable Labyrinth Domain Structures in a van der Waals Itinerant Ferromagnet Cr7Te8
Authors: Meng 孟 Kui 奎 , Li 李 Zeya 泽亚 , Shen 申 Yicheng 艺成 , Bi 毕 Xiangyu 翔宇 , Rao 饶 Junhao 俊豪 , Qian 钱 Yuting 玉婷 , Gao 高 Zhansheng 战胜 , Chen 陈 Peng 朋 , Qiu 邱 Caiyu 彩玉 , Qin 秦 Feng 峰 , Wu 吴 Jinxiong 金雄 , Luo 罗 Feng 锋 , Huang 黄 Junwei 俊伟 , Yuan 袁 Hongtao 洪涛
Published: August 2024

Manipulating magnetic domain structure plays a key role in advanced spintronics devices. Theoretical rationale is that the labyrinthine domain structure, normally appearing in ferromagnetic thin films with strong magnetic anisotropy, shows a great potential to increase data storage density for designing magnetic nonvolatile memory and logic devices. However, an electrical control of labyrinthine domain structure remains elusive. Here, we demonstrate the gate-driven evolution of labyrinthine domain structures in an itinerant ferromagnet Cr7Te8. By combining electric transport measurements and micromagnetic finite difference simulations, we find that the hysteresis loop of anomalous Hall effect in Cr7Te8 samples shows distinct features corresponding to the generation of labyrinthine domain structures. The labyrinthine domain structures are found to be electrically tunable via Li-electrolyte gating, and such gate-driven evolution in Cr7Te8 originates from the reduction of the magnetic anisotropic energy with gating, revealed by our micromagnetic simulations. Our results on the gate control of anomalous Hall effect in an itinerant magnetic material provide an opportunity to understand the formation and evolution of labyrinthine domain structures, paving a new route towards electric-field driven spintronics.
Microscopic Magnetism of Nickel-Based Infinite-Layer Superconducting Parent Compounds RNiO2 (R = La, Nd): A μSR Study
Authors: Wu 吴 Qiong 琼 , Fu 付 Ying 盈 , Wang 王 Le 乐 , Zhou 周 Xuefeng 雪峰 , Wang 王 Shanmin 善民 , Zhu 朱 Zihao 子浩 , Chen 陈 Kaiwen 锴文 , Jiang 姜 Chengyu 程予 , Shiroka Toni , Hillier Adrian D. , Mei 梅 Jia-Wei 佳伟 , Shu 殳 Lei 蕾
Published: August 2024

By using muon spin relaxation (μSR) measurements, we perform a comparative study of the microscopic magnetism in the parent compounds of infinite-layer nickelate superconductors RNiO2 (R = La, Nd). In either compound, the zero-field μSR spectra down to the lowest measured temperature reveal no long-range magnetic order. In LaNiO2, short-range spin correlations appear below T = 150 K, and spins fully freeze below T ∼ 10 K. NdNiO2 exhibits a more complex spin dynamics driven by the Nd 4f and Ni 3d electron spin fluctuations. Further, it shows features suggesting the proximity to a spin-glass state occurring below T = 5 K. In both compounds, the spin behavior with temperature is further confirmed by longitudinal-field μSR measurements. These results provide new insight into the magnetism of the parent compounds of the superconducting nickelates, crucial to understanding the microscopic origin of their superconductivity.
Impact of nanosilver surface electronic distributions on serum protein interactions and hemocompatibility
Authors: Rivero Paula S , Pistonesi Denise B , Belén Federico , Centurión M Eugenia , Benedini Luciano A , Rauschemberger M Belén , Messina Paula V
Published: August 2024

The translation of silver-based nanotechnology ‘from bench to bedside’ requires a deep understanding of the molecular aspects of its biological action, which remains controversial at low concentrations and non-spherical morphologies. Here, we present a hemocompatibility approach based on the effect of the distinctive electronic charge distribution in silver nanoparticles (nanosilver) on blood components. According to spectroscopic, volumetric, microscopic, dynamic light scattering measurements, pro-coagulant activity tests, and cellular inspection, we determine that at extremely low nanosilver concentrations (0.125–2.5 μg ml−1), there is a relevant interaction effect on the serum albumin and red blood cells (RBCs). This explanation has its origin in the surface charge distribution of nanosilver particles and their electron-mediated energy transfer mechanism. Prism-shaped nanoparticles, with anisotropic charge distributions, act at the surface level, generating a compaction of the native protein molecule. In contrast, the spherical nanosilver particle, by exhibiting isotropic surface charge, generates a polar environment comparable to the solvent. Both morphologies induce aggregation at NPs/bovine serum albumin ≈ 0.044 molar ratio values without altering the coagulation cascade tests; however, the spherical-shaped nanosilver exerts a negative impact on RBCs. Overall, our results suggest that the electron distributions of nanosilver particles, even at extremely low concentrations, are a critical factor influencing the molecular structure of blood proteins’ and RBCs’ membranes. Isotropic forms of nanosilver should be considered with caution, as they are not always the least harmful.
A family of integrable maps associated with the Volterra lattice
Authors: Hone A N W , Roberts J A G , Vanhaecke P
Published: August 2024

Recently Gubbiotti, Joshi, Tran and Viallet classified birational maps in four dimensions admitting two invariants (first integrals) with a particular degree structure, by considering recurrences of fourth order with a certain symmetry. The last three of the maps so obtained were shown to be Liouville integrable, in the sense of admitting a non-degenerate Poisson bracket with two first integrals in involution. Here we show how the first of these three Liouville integrable maps corresponds to genus 2 solutions of the infinite Volterra lattice, being the g = 2 case of a family of maps associated with the Stieltjes continued fraction expansion of a certain function on a hyperelliptic curve of genus

g
⩾
1

. The continued fraction method provides explicit Hankel determinant formulae for tau functions of the solutions, together with an algebro-geometric description via a Lax representation for each member of the family, associating it with an algebraic completely integrable system. In particular, in the elliptic case (g = 1), as a byproduct we obtain Hankel determinant expressions for the solutions of the Somos-5 recurrence, but different to those previously derived by Chang, Hu and Xin. By applying contraction to the Stieltjes fraction, we recover integrable maps associated with Jacobi continued fractions on hyperelliptic curves, that one of us considered previously, as well as the Miura-type transformation between the Volterra and Toda lattices.
The Euler non-mixing made easy
Authors: Khesin Boris
Published: August 2024

The non-transitivity without extra constraints in the Euler equation in any dimension is almost evident and can be derived, e.g. from Morse theory.
Thermoelectric properties of

Sn

2

SSe

via band engineering with Ge alloying
Authors: Kaur Baljinder , Khandy Shakeel Ahmad , Dhiman Shobhna , Albaqami Munirah D , Kaur Kulwinder
Published: August 2024

The thermoelectric properties of

Sn

2

SSe

are investigated via band engineering using Ge alloying. In this work, the electronic and thermoelectric properties of

Sn

2

SSe

doped with Ge at different concentrations (x=0, 0.25, 0.5, 0.75, and 1) are investigated using density functional theory and Boltzmann transport theory. At 300K, the Seebeck coefficient and electrical conductivity are enhanced with Ge alloying from −960μV/K to −1535 μV/K and from 3.4 × 105 S/cm to 4.1 × 105 S/cm respectively. However, the lowest value of lattice thermal conductivity is observed at 700 K which is 2.7W/mK. At x = 1, A remarkably high ZT value 1.7 is achieved at 700 K for

Sn

2
(
1
−
x
)

Ge

2
(
x
)

SSe

. The high ZT value is 1.8 times greater than pure compound.
Novel grayscale image encryption based on 4D fractional-order hyperchaotic system, 2D Henon map and knight tour algorithm
Authors: Ullah Saeed , Liu Xinge , Waheed Adil , Zhang Shuailei , Li Shan
Published: August 2024

With the increasing frequency of data exchange, the security of transmitted information, especially images, has become paramount. This paper proposes a novel algorithm for encrypting grayscale images of any dimension by using a proposed fractional-order (FO) 4D hyperchaotic system, 2D Henon chaotic map permutation, and the knight tour algorithm. Initially, chaotic sequences are generated by utilizing the proposed FO 4D hyperchaotic system, which are later employed to rearrange and shuffle the entire image pixels to bolster the efficacy of image encryption. To introduce an additional layer of diffusion, 2D Henon chaotic map permutation is used. Furthermore, the knight tour algorithm is applied by starting from a chosen point and executing specified rounds on the scrambled image to increase the encryption’s robustness. The resultant image encryption algorithm undergoes thorough testing and evaluation. It exhibits high sensitivity to the encryption key and boasts a larger key space, rendering it more resistant to brute-force attacks. The proposed algorithm demonstrates an approximate correlation of 0 between adjacent pixels. Further, encryption of a grayscale image of size 256 × 256 takes approximately 0.4 seconds, rendering it more suitable for cryptographic purposes.
Entropy generation in newtonian vs non-newtonian nanofluid flow under vibration
Authors: Mishra Santosh Kumar , Mishra Alka , Singh Pushpendra
Published: August 2024

Numerical investigation into the effects of vibration on heat transfer and entropy generation in Newtonian and Non-Newtonian nanofluid flows through pipes reveals enhanced heat transfer via intensified fluid agitation and improved particle dispersion. Thermal entropy generation analysis shows reduced irreversibility in vibrated flow, indicating improved flow mixing. Vibration enhances heat transfer by intensifying fluid agitation and promoting particle dispersion near the wall, resulting in a significantly more uniform temperature distribution along the pipe, approximately 100 times more than steady-state flow. This study underscores vibration’s potential to optimize heat transfer and reduce entropy generation in nanofluid systems, emphasizing velocity and rheological impacts. Comparison of vibrated flow to steady-state flow for Newtonian and non-Newtonian fluids reveals significant improvements under vibration, particularly at lower Reynolds numbers where non-Newtonian fluids exhibit pronounced effects. Future research directions include exploring thermal radiation’s impact on entropy generation, analyzing different nanofluid compositions, and investigating varied boundary conditions and geometries to advance understanding in this field. This study provides valuable insights into the complex interplay among vibration, fluid dynamics, and heat transfer in nanofluid flows. Its findings have practical implications for optimizing thermal management systems in diverse engineering applications.
Simulations of the optical diffraction patterns produced by the pressure field of a clinical shock wave source
Authors: García-Ramírez Fernando E , Loske Achim M , Avila Remy
Published: August 2024

Today, shock waves are used to treat a wide variety of ailments. Consequently, there is a need to develop efficient methodologies for comparing and evaluating the pressure fields generated by different equipment. Hydrophones are commonly utilized for accurate pressure measurements although they can be damaged by pitting due to acoustic cavitation. Furthermore, the range of measurement is limited by the position of the device. Optical methods have also been proposed since the presence of a disturbing device in the wave propagation medium is not necessary, and they provide a broader registering field. Nevertheless, these methods do not provide accurate measurements compared with those obtained with polyvinylidene difluoride or fiber-optic hydrophones. Herein, an optical method for shock wave characterization based on diffraction analysis, that can lead to more precise results, is proposed. The phase fluctuations of a light wave produced when it traverses the shock wave pressure field are calculated. The diffraction patterns produced by this perturbed wave at an observation plane at different propagation distances are presented. Considering the state of the art of high-speed cameras, we conclude that an experimental setup, based on the results reported here, can contribute to the evaluation and comparison of shock wave generators for medical applications.
Four-wheel steering vehicle trajectory tracking control based on PSO optimized MPC
Authors: Li Shaohua , Yang Zekun , Li Baolu
Published: August 2024

In order to address the difficulty induced by controller parameter uncertainty in trajectory tracking control of four-wheel steering vehicles(4WS), a trajectory tracking control method for unmanned vehicles based on particle swarm optimization (PSO) is proposed to improve the robustness of the controller. The approach involves the use of model predictive control (MPC) for implementing trajectory tracking control for the unmanned vehicle. Iterative optimization is conducted by utilizing the integral time absolute error (ITAE) as the objective function, which involves multiplying the time integral of lateral deviation and yaw rate deviation. This process ultimately determines the optimized MPC weight matrix parameters. Co-simulation using CarSim/Simulink reveals a remarkable reduction of 46.1% in the maximum longitudinal error, and the optimization proves effective across various vehicle speed conditions. Experimental results validate the effectiveness of the proposed control strategy, with the 4WS control strategy yielding a maximum longitudinal error of 0.28 meters, affirming that the overall controller design successfully accomplishes its intended objectives.
Vortex superlattice induced second-order topological mid-gap states in first-order topological insulators and superconductors
Authors: He Jing , Yan Yu , Wu Ya-Jie
Published: August 2024

Topological defects such as vortex and dislocations, support zero-energy localized states as a reflection of the bulk topology, in first-order topological insulators and superconductors. Furthermore, emergent first-order topological mid-gap states have been discovered driven by the magnetic vortex superlattice. However, whether the higher-order topological mid-gap states would emerge from the first-order topological insulators and superconductors with the vortex superlattice remains elusive. In this work, we propose vortex superlattice could induce second-order topological mid-gap states with staggered lattice spacings for vortices in first-order topological insulators and superconductors. These higher-order topological mid-gap states originate from the staggered tunneling between vortex-induced bound states and the emergent π flux on vortex superlattices, as an intrinsic exhibition of the interplay between vortices and bulk topology for the first-order topological states. Our work uncovers higher-topological characteristics of topological-defect superlattice in first-order topological states, and develops a controllable environment for the creation and exploration of higher-order topological states.
Characterization of interface states and investigation of possible current conduction mechanisms in the Pt, Au, Cu/n-InP Schottky diodes
Authors: Kim Hogyoung
Published: August 2024

Based on the capacitance/conductance–voltage (C/G–V) and current–voltage (I–V) methods, the interface characteristics and the current conduction mechanisms of Pt/n-InP Schottky contacts were studied in detail. The interface states strongly affected the values of capacitance in the depletion region. From Terman, G–V, and forward I–V methods, the interface state density (D
it) was found to range from mid-1012 to mid-1013 eV−1cm−2. The forward current characteristics was not elucidated by the thermionic emission (TE) model assisted by tunneling via the interfacial layer. Rather, the spatially distributed inhomogeneous barrier could interpret the forward current characteristics. Trap-assisted tunneling involving phosphorous vacancy (VP)-related defects was observed to be dominant in the case of the reverse current characteristics. The comparison of Pt metal contact with Cu and Au contacts revealed that Pt contact has the highest D
it among three contacts.
Statistical properties of ideal photons in a two-dimensional dye-filled spherical cap cavity
Authors: Cheng 成 Ze 泽
Published: August 2024

Within the framework of quantum statistical mechanics, we have proposed an exact analytical solution to the problem of Bose–Einstein condensation (BEC) of harmonically trapped two-dimensional (2D) ideal photons. We utilize this analytical solution to investigate the statistical properties of ideal photons in a 2D dye-filled spherical cap cavity. The results of numerical calculation of the analytical solution agree completely with the foregoing experimental results in the BEC of harmonically trapped 2D ideal photons. The analytical expressions of the critical temperature and the condensate fraction are derived in the thermodynamic limit. It is found that the 2D critical photon number is larger than the one-dimensional (1D) critical photon number by two orders of magnitude. The spectral radiance of a 2D spherical cap cavity has a sharp peak at the frequency of the cavity cutoff when the photon number exceeds the critical value determined by a temperature.
Fast nonlinear scattering of runaway electron beams through resonant interactions with plasma waves
Authors: Lin Kang Hye , Dae Yoon Young , Cho Myung-Hoon , Yun Gunsu S.
Published: August 2024

The resonant interaction between a runaway electron (RE) beam and a reactor-grade background plasma is investigated through two-dimensional particle-in-cell simulations, employing a simplified model of the system. The temporal evolutions of the electron momentum distribution function for two separate initial beam energies (1 and 10 MeV) are tracked, revealing the occurrence of plasma wave growth concomitant with pitch angle scattering or momentum distribution diffusion within the RE beam. Notably, we identify and confirm the dependence of the dominant resonance condition on the initial kinetic energy of the RE beam. Furthermore, we quantify the effect of particle-wave interactions on the RE momentum distribution diffusion by assessing the average kinetic energy flux from the RE distribution function.
Line optimization of multi-beam sonar sounding technology in ocean surveying and mapping
Authors: Li Mengjia , Zhou Zien , Lyu Shaowei , Liang Mengxuan , Gao Zixuan , Xia Chengming
Published: August 2024

In this paper, the problem of line optimization existing in the practical application of multi-beam sonar-sounding technology is studied. Firstly, by analyzing the working principle of multi-beam sonar, the multi-beam coverage width model and the overlap rate model between adjacent strips are established considering the slope of seabed terrain. Then, a more general parameterized multi-beam coverage width formula with an adjustable azimuth angle of the line is derived under three-dimensional space coordinates. Then, the minimum total line length is defined as the objective function, and the constraint conditions of overlap rate and complete coverage are added to establish the mathematical model of line planning. Then, an iterative algorithm is designed to quickly determine the line spacing, and an improved particle swarm optimization algorithm, including a trigonometric function change learning factor, is used to search for the optimal line layout. Finally, the simulation results show that the optimized scheme can reduce the total line length by 2% compared with the unoptimized line layout, which verifies the effectiveness of the established model and algorithm. This study provides a theoretical basis for navigation planning and shipboard system optimization of multi-beam sonar survey. Subsequent work taking into account the influence of complex sea conditions, efforts were made to expand the model’s applicability.
Evaluation of sodium hyaluronate-based composite hydrogels for prevention of nasal adhesions
Authors: Padalhin Andrew , Ryu Hyun Seok , Yoo Seung Hyeon , Abueva Celine , Seo Hwee Hyon , Park So Young , Min Jun Won , Chung Phil-Sang , Woo Seung Hoon
Published: August 2024

During the healing process after intra-nasal surgery, the growth and repair of damaged tissues can result in the development of postoperative adhesions. Various techniques have been devised to minimize the occurrence of postoperative adhesions which include insertion of stents in the middle meatus, application of removable nasal packing, and utilizing biodegradable materials with antiadhesive properties. This study assesses the efficacy of two sodium hyaluronate (SH)–based freeze-dried hydrogel composites in preventing postoperative nasal adhesions, comparing them with commonly used biodegradable materials in nasal surgery. The freeze-dried hydrogels, sodium hyaluronate and collagen 1(SH-COL1) and sodium hyaluronate, carboxymethyl cellulose, and collagen 1 (SH-CMC-COL1), were evaluated for their ability to reduce bleeding time, promote wound healing, and minimize fibrous tissue formation. Results showed that SH-CMC-COL1 significantly reduced bleeding time compared to both biodegradable polyurethane foam and SH-COL1. Both SH-COL1 and SH-CMC-COL1 exhibited enhanced wound healing effects, as indicated by significantly greater wound size reduction after two weeks compared to the control. Histological analyses revealed significant differences in re-epithelialization and blood vessel count among all tested materials, suggesting variable initial wound tissue response. Although all treatment groups had more epithelial growth, with X-SCC having higher blood vessel count at 7 d post treatment, all treatment groups did not differ in all histomorphometric parameters by day 14. However, the long-term application of SH-COL1 demonstrated a notable advantage in reducing nasal adhesion formation compared to all other tested materials. This indicates the potential of SH–based hydrogels, particularly SH-COL1, in mitigating postoperative complications associated with nasal surgery. These findings underscore the versatility and efficacy of SH–based freeze-dried hydrogel composites for the management of short-term and long-term nasal bleeding with an anti-adhesion effect. Further research is warranted to optimize their clinical use, particularly in understanding the inflammatory factors influencing tissue adhesions and assessing material performance under conditions mimicking clinical settings. Such insights will be crucial for refining therapeutic approaches and optimizing biomaterial design, ultimately improving patient outcomes in nasal surgery.
Estimating effects of monsoon flooding on household water access
Authors: Broyles Lauren M T , Pakhtigian Emily L , Mejia Alfonso
Published: August 2024

The importance of climate in water resources management is well recognized, but less is known about how climate affects water access at the household level. Understanding this is crucial for identifying vulnerable households, reducing health and well-being risks, and finding equitable solutions. Using difference-in-differences regression analyses and relying on temporal variation in interview timing from multiple, cross-sectional surveys, we examine the effects of monsoon riverine flooding on household water access among 34 000 households in Bangladesh in 2011 and 2014. We compare water access, a combined measure of both water source and time for collection, among households living in flood-affected and non-flood-affected districts before and after monsoon flooding events. We find that households in monsoon flood-affected districts surveyed after the flooding had between 2.27 and 4.42 times higher odds of experiencing low water access. Separating geographically, we find that while households in coastal districts have lower water access than those in non-coastal districts, monsoon flood exposure is a stronger predictor of low water access in non-coastal districts. Non-coastal districts were particularly burdened in 2014, when households affected by monsoon flooding had 4.71 times higher odds of low water access. We also find that household wealth is a consistent predictor of household water access. Overall, our results show that monsoon flooding is associated with a higher prevalence of low water access; socioeconomically vulnerable households are especially burdened.
Analyzing the evanescent field ratio of ridge waveguide based on different material platforms for sensing applications
Authors: Butt Muhammad Ali
Published: August 2024

In this study, a comprehensive numerical investigation focusing on a ridge waveguide composed of various material platforms is undertaken, including silicon-on-insulator (SOI), silicon nitride (SiN), and SU-8 polymer. In the realm of photonic sensing devices, the evanescent field assumes paramount significance in facilitating light-matter interactions. The primary objective of this study is to furnish a comparative analysis discerning the suitability of these material platforms for sensing applications. The findings reveal distinct characteristics among the different material platforms. SOI emerges as a standout contender, exhibiting an augmented evanescent field ratio that substantially enhances light-matter interaction. Following closely, SiN-based waveguides demonstrate commendable performance in this regard. Conversely, SU-8 polymer waveguides, characterized by larger dimensions, present limitations in evanescent field confinement, resulting in the lowest sensitivity among the materials investigated. Hence, the selection of the appropriate material platform and waveguide type emerges as a critical consideration in the design phase of photonic sensors. This decision significantly influences the sensor’s performance and efficacy in real-world applications.
Effects of boron on microstructure, wear and corrosion properties of external magnetic field assisted laser metal deposition coatings
Authors: Qi Kang , Jiang Long
Published: August 2024

Coatings with different boron content were prepared by magnetic field-assisted Co-based laser metal deposition on 300 M ultra-high strength steel. The effects of boron content on the magnetic properties, mechanical properties, friction and wear properties, and corrosion resistance of the coating were investigated. The research results indicate that adding 6 wt% of boron to cobalt alloy in a 35 mT alternating magnetic field is beneficial for refining the microstructure, which can improve the mechanical properties of the coating. This research also discusses the effect of boron content on the wear and corrosion resistance of the coating. The results show that adding boron content enhances the magnetostrictive effect, and reduces the elastic modulus of the laser metal deposition coating while ensuring its hardness, thereby improving the wear and corrosion resistance of the laser metal deposition layer. The hardness of the coating can reach 1215 HV. The friction coefficient and corrosion current density of the coating are reduced by 26.9% and 60.2% respectively compared with the substrate. This work can help promote the application of laser metal deposition technology, reduce costs, and ensure performance.
Microstructure and mechanical property improvement of concurrent wire-powder feeding laser melting deposition Ti-6Al-4V via TiC addition
Authors: Wang Chenyang , Xing Fei , Liu Xiangyu , Bian Hongyou , Liu Weijun
Published: August 2024

Wire-feed laser metal deposition (LMD-W) offers a high deposition rate and low cost, making it an effective solution for reducing costs and enhancing efficiency in manufacturing large-scale titanium aerospace components. Currently, the material used for LMD-W is typically a single alloy wire, which limits the flexibility and functionality of manufacturing composite materials. This work employed a novel concurrent wire-powder feeding laser metal deposition (LMD-WP) process to manufacture TiC/Ti-6Al-4V composite. In the LMD-WP method, Ti-6Al-4V wire was fed laterally, while TiC particles were delivered coaxially. Only 1.0 wt% TiC particles were added to prevent excessive TiC, which could cause stress concentration and increase crack sensitivity. The microstructure and mechanical properties of Ti-6Al-4V alloy and TiC/Ti-6Al-4V composite were investigated. The results indicate that with coaxial TiC particle addition, the α-Ti in TiC/Ti-6Al-4V is noticeably refined. Additionally, in situ TiC acts as heterogeneous nucleation sites, restricting α-Ti growth and reducing its aspect ratio. Furthermore, TiC particles weakened the α-Ti texture in the (0001) and (11–20) directions. Moreover, adding TiC particles significantly enhanced tensile strength, with the yield strength reaching 950 MPa and the ultimate tensile strength reaching 1048 MPa. Compared to Ti-6Al-4V alloy fabricated by LMD-W, this represents an increase of 11.25% and 10.72%, respectively. The improvement in tensile properties is principally ascribed to grain boundary strengthening, Orowan strengthening and dislocation density strengthening. This work introduces an innovative approach and abundant data for the additive manufacturing of TiC/Ti-6Al-4V composite with high efficiency and low cost.