bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of the development of solar photovoltaic industry on the relationship between supply and demand of key minerals in China
Authors: Guo Qing , Wu Kaiyi
Published: May 2024

The importance of mineral resources cannot be ignored in the country's economic and social development and is of vital significance in securing China's continued economic and social prosperity. Against the backdrop of the country's active promotion of the clean energy industry, the booming development of the photovoltaic industry has triggered a growing demand for its key raw materials, especially important metallic minerals. Based on the system dynamics theory, the article uses Vensim to construct a photovoltaic cell-key metal mineral simulation model to analyze the development of China's photovoltaic industry in depth and focuses on its far-reaching impact on the supply and demand relationship of key minerals. The results of the study show that (1) China's photovoltaic cells show strong growth; (2) recycling and technology substitution can significantly reduce the risk of copper and aluminum supply and demand imbalance; and (3) technology substitution is more effective than recycling in reducing the supply and demand imbalance of copper and aluminum. Based on the above-mentioned findings, the article puts forward corresponding policy recommendations.
Electrical properties of bisphenol-A-free magnetoactive borosilicate polymers
Authors: Loo Xuyan , Nagaraju Bhavana , Pathivada Sai , Bartsch Alexander , Schratzenstaller Thomas , Sattler Robert , Monkman Gareth J.
Published: May 2024

The recent REACH regulations require the elimination of bisphenol-A and titanium dioxide from commercially available boron-based polymers. This has led to changes in some of the mechanical characteristics, which strongly influence the properties of magnetoactive borosilicate polymers. This work delivers results on the electrical properties and discusses some implications for future research using bisphenol-A and titanium-dioxide-free substitutes.
Effects of streamwise-elongated and spanwise-periodic surface roughness arrays on supersonic boundary-layer instability
Authors: Zheng Jianing , Wu Xuesong
Published: May 2024

We investigate the influence of streamwise-elongated and spanwise-periodic roughness arrays on the supersonic boundary-layer instability under the assumption of a high Reynolds number. The main focus is on the lower-branch viscous instability modes, and the spanwise spacing of the roughness arrays is taken to be comparable to the characteristic wavelength of the modes (which is on the triple-deck scale), so that most significant effects can be generated. The streamwise length scale of the elements is much greater than the spanwise length scale. The roughness height is determined by requiring the change of the wall shear to be O(1). The equations governing the nonlinear roughness-induced streaky flow are deduced from the standard triple-deck theory. These equations are parabolic in the streamwise direction and are solved using a streamwise marching method to characterize the evolution of streaky structures. The linear stability of the streaky flow is analyzed. By exploiting the asymptotic structure, the bi-global eigenvalue problem is reduced to a one-dimensional one, where the stability is found to be controlled by the spanwise-dependent wall shear. The reduced eigenvalue problem is solved numerically. The results show that roughness arrays inhibit instability modes with moderate frequencies but promote high-frequency modes. Roughness elements of greater height have stronger effects on the linear stability. The shape of roughness elements plays an important role. A significant feature, different from the subsonic case, is that fundamental and superharmonic resonance modes radiate sound waves spontaneously into the far field.
Reconstruction of turbulence characteristics from fluctuation reflectometry measurements in the nonlinear regime
Authors: Tretinnikov P. , Gusakov E. , Heuraux S.
Published: May 2024

The nonlinear theory of radial correlation reflectometry (RCR) predicts that the cross correlation function of a signal follows a Gaussian distribution with a cutoff separation, where the correlation length is determined by both the turbulence amplitude and its radial correlation length. In contrast, phase spectrum analysis provides information solely on the turbulence amplitude. This work describes the possibility of applying both signal analysis methods and demonstrates that turbulence amplitude and radial correlation length can be simultaneously measured using RCR diagnostics in the nonlinear regime.
A multi-physics correction of the shear-stress transport turbulence model for supersonic flows
Authors: Zeng Yu , Wang Hongbo , Xiong Dapeng , Yang Yixin , Sun Mingbo , Liu Weidong
Published: May 2024

Though the k–ω shear-stress transport (SST) turbulence model is widely used, it is developed based on incompressible flow and the analysis of simple flow characteristics such as boundary layer and free shear flows. Due to the lack of comprehensive consideration of important flow structures, such as shock wave and highly compressible zones, the k–ω SST turbulence model has inherent limitations in describing supersonic flows. A multi-physics improvement strategy is proposed to improve the prediction accuracy of the k–ω SST model for supersonic flows. This strategy leverages shock/turbulent boundary layer and shock/compressibility functions to accurately recognize areas with significant structures, enabling targeted improvement of the turbulence model. Five supersonic flow cases are tested and analyzed, and the results show that while the single-physics turbulence model can improve the prediction accuracy of flows with a single flow structure corresponding to the correction, its prediction ability is insufficient in other flows with different flow structures. In contrast, the multi-physics turbulence model exhibits good ability in flows with multiple flow structures, while also maintaining the performance of the single-physics turbulence model. The multi-physics turbulence model has higher accuracy and stronger universality, making it advantageous for modeling complex supersonic flows.
An innovative booster-assisted dynamically installed fish anchor and its installation characteristics considering the action of ocean currents
Authors: Zhang Biao , Fu Yong
Published: May 2024

The fish anchor is an economically viable offshore foundation engineering technology that has been proposed in recent years. By fish anchor, we mean a fish-shaped dynamically installed anchor that can penetrate into the seabed through water by its own weight. However, the existing research studies seldom consider the hydrodynamic characteristics of its free fall installation, resulting in uncertainties regarding its underwater installation characteristics. Therefore, based on OpenFOAM, this study first investigated the directional stability of fish anchors during its underwater falling process through the static model analysis method and dynamic model analysis method. The findings indicated that the directional stability of fish anchors was insufficient, rendering them suitable only for release and installation at low heights (i.e., less than 4.2 times the anchor length) without marine environmental loads. Furthermore, the anchor inclination angle during installation is significant, thereby impacting its penetration depth and pull-out capacity in the seabed. To solve this problem, the concept of an innovative booster-assisted fish anchor is proposed, which can significantly enhance the directional stability of conventional fish anchors. Results show that the maximum installation height of the new booster-assisted fish anchor is increased by 2.4 times compared to the original design, thereby enhancing both the penetration speed and uplift capacity. Based on the findings, recommended installation and construction conditions are provided. Finally, a predictive formula for the installation height and verticality of the new booster-assisted fish anchor under current action is presented to offer guidance for engineering applications.
Ionic control of magnetism in all-solid-state CoOx/yttria-stabilized zirconia heterostructures
Authors: Ma Zheng , Tan Zhengwei , Quintana Alberto , Spasojevic Irena , López-Pintó Nicolau , Sánchez Florencio , Fina Ignasi , Herrero-Martín Javier , Menéndez Enric , Sort Jordi
Published: May 2024

Magneto-ionic gating, a procedure that enables the modulation of materials' magnetic properties by voltage-driven ion motion, offers alternative perspectives for emerging low-power magnetic storage and spintronic applications. Most previous studies in all-solid-state magneto-ionic systems have focused on the control of interfacial magnetism of ultrathin (i.e., 1–3 nm) magnetic films, taking advantage of an adjacent ionic conducting oxide, usually GdOx or HfOx, that transports functional ionic species (e.g., H+ or O2−). Here, we report on room-temperature OFF–ON ferromagnetism by solid-state magneto-ionics in relatively thick (25 nm) patterned CoOx films grown on an yttria-stabilized zirconia (YSZ) layer, which acts as a dielectric to hold electric field and as an O2− ion reservoir. Upon negatively biasing, O2− ions from the CoOx tend to migrate toward the YSZ gate electrode, leading to the gradual generation of magnetization (i.e., OFF-to-ON switching of a ferromagnetic state). X-ray absorption and magnetic circular dichroism studies reveal subtle changes in the electronic/chemical characteristics, responsible for the induced magnetoelectric effects in such all-oxide heterostructures. Recovery of the initial (virtually non-magnetic) state is achieved by application of a positive voltage. The study may guide future development of all-solid-state low-power CMOS-compatible magneto-ionic devices.
Ion migration effects during hydro-fracturing of deep high salinity coal seam
Authors: Ma Ruying , Yao Yanbin , Feng Dong , Wu Hao , Vandeginste Veerle , Wang Zefan , Zhang Xiaona
Published: May 2024

Hydraulic fracturing enables effective exploitation of deep coalbed methane. During the hydraulic fracturing process, high salinity flowback fluid is generated, and this poses a significant challenge for water treatment. Therefore, we investigate the effect of hydraulic fracturing on ion migration in deep coal seams and its underlying mechanisms. In this study, nuclear magnetic resonance, inductively coupled plasma mass spectrometry, scanning electron microscopy, and energy dispersive x-ray spectroscopy were utilized to systematically study the diffusion behavior of ions and its correlation with water imbibition. Our results show that imbibition equilibrium was reached before ion diffusion finished. Ion diffusion displays three linear stages followed by a plateau part, and the second segment is the fastest one. The water–coal interactions result in the diffusion of ions into solution, with the most significant increases in Ca2+, Mg2+, Na+, K+, Li+, Cu2+, V5+, Hg2+, Pb2+, B3+, Mo6+, Cr3+, Sn4+, Cd2+, Cs+, Sr2+, and Ba2+. The dissolution of calcite, sodium feldspar, and kaolinite are the main contributions for ion migration. In addition, these reactions not only cause the release of ions into the solution but also lead to the formation of secondary pore-fractures and secondary precipitation. The results of this work help to understand better the ion migration induced by the water–coal interaction and to evaluate the fluid properties in deep coal formations.
Optoelectronically controlled spin-valley filter and nonlocal switch based on an asymmetrical silicene magnetic superconducting heterostructure
Authors: Ma Shuo , Zhang Hongmei , Liu Jianjun , Liu De
Published: May 2024

We investigate the effects of the circularly polarized light (CPL) and the electric field (EF) on the nonlocal transport in a silicene-based antiferromagnet/superconductor/ferromagnet (AF/S/F) asymmetrical junction. For case I (II), the CPL and the EF are applied simultaneously in the antiferromagnetic (ferromagnetic) region, whereas in the ferromagnetic (antiferromagnetic) region, only a constant EF is considered. The spin-valley-resolved conductance can be turned on or off by adjusting the CPL or the EF. The AF/S/F junction can be manipulated as a spin-locked valley filter for case I, while for case II, it can be used not only as a valley-locked spin filter but also as a nonlocal switch between two pure nonlocal processes. Such interesting nonlocal switch effect can be effectively controlled by reversing the direction of the incident energy axis, the handedness of the CPL, or the direction of the EF. These findings may open an avenue to the design and manufacture of the spintronic and valleytronic devices based on the asymmetrical silicene magnetic superconducting heterostructure.
Simulation of light propagation in medium with an ultrasonically induced refractive index gradient
Authors: Harada Y. , Ishikawa M. , Kuroda Y. , Matsukawa M. , Koyama D.
Published: May 2024

Modulation of the refractive index in a medium by external stimuli enables fast and reversible control of light propagation. This technology for controlling light has led to new discoveries in a wide range of research fields from physics to life sciences and has played a major role in the development of photonics devices. In this article, we focus on ultrasound as an external stimulus and have devised a method to control the refractive index of a medium using ultrasound. Our research group has previously discovered that a giant refractive-index gradient (Δn on the order of 10−2) was induced when water was irradiated with high-frequency (100 MHz range), high-intensity (on the order of MPa) ultrasound. Here, we report ray-tracing simulations in a medium with a refractive-index gradient induced by ultrasonic radiation. A numerical model of the refractive-index gradient was developed based on the experimental data, and ray-tracing simulations were performed using the Euler–Lagrange equation. The ray-tracing simulation results were close numerically to the profiles of the laser beam observed in the experiment when the laser beam was incident on the refractive-index-gradient medium.
Thermo-hydraulic performance evaluation of heat transfer tubes with different configuration forms
Authors: Liao Wenling , Jing Zhengbiao
Published: May 2024

Fluid mixing induced by changes in tube direction is an effective method to enhance the heat transfer performance of heat transfer tubes. This study proposes three types of configuration forms for heat transfer tubes that improve their thermo-hydraulic performance, named cases 1, 2, and 3. Case 1 is distributed on the same plane and has the following configuration form: horizontal to vertical upward to horizontal to vertical downward to horizontal. Cases 2 and 3 transform the front and rear tubes into two parallel planes through the middle horizontal tube, with a 180° difference at the outlet direction. The thermo-hydraulic performance of heat transfer tubes with different configuration forms is evaluated by quantitative comparison of the Nusselt number (Nu), friction coefficient (f), and performance evaluation criterion (PEC), within a Reynolds number range of 5000–40 000. The distribution results of velocity, streamline, turbulent kinetic energy, skin friction coefficient, and so on are analyzed to reveal the underlying mechanisms of difference in the thermo-hydraulic performance of heat transfer tubes with different configurations. The results show that the thermo-hydraulic performance of heat transfer tubes with different configurations is better than that of a straight tube due to induced fluid mixing within the tube. In addition, case 1 rather than cases 2 and 3 has a more significant influence on the thermo-hydraulic performance of heat transfer tubes, especially at high Reynolds numbers, and the maximum PEC of case 1 exceeds cases 2 and 3 by 6% and 8.5%, respectively. Furthermore, the decrease in connection length of case 1 improves the heat transfer performance, which is more pronounced at high Reynolds numbers. These research findings serve as a valuable reference for designing heat transfer tube configurations to enhance heat transfer efficiency.
Experimental study on evaluating hydrodynamic performance of a novel submerged floating tunnel
Authors: Wu Zhiwen , Meng Xiangzhang , Xie Canrong , Qin Yinghong , Garg Ankit , Mei Guoxiong
Published: May 2024

A submerged floating tunnel (SFT) is susceptible to significant vibrational responses when subjected to intricate and challenging conditions of the deep-water ocean environment. This is primarily due to the inherent attributes of large flexibility and lower damping exhibited by flexible components of an SFT. To the best of the authors' knowledge, a majority of the current SFT concepts do not completely satisfy the motion-limit values mandated by the relevant standards. In this study, a novel SFT concept is introduced to bolster its vibration suppression capacity through the optimization of the superstructure and substructure by using a three-tube structure and a rigid truss structure, respectively. To evaluate the efficacy of the novel SFT, a comprehensive series of experiments are conducted in a wave-current flume to scrutinize the vibration suppression performance of this novel SFT configuration, juxtaposed against conventional design concepts. The insights are revealed based on a comparative analysis in both the time and frequency domains, encompassing a range of key parameters, and by performing a sensitivity analysis specific to the present model. The results show that the superposition effect of wave and current coupling has a lower impact on the motion response of the proposed SFT with higher mooring stiffness. Despite the increase in cable tension (1–2 times) for the proposed SFT design, the corresponding vibration suppression performance is found to improve by 3–9 times. This experimental investigation holds profound theoretical and engineering significance, as it contributes pivotal knowledge to the field of vibration suppression for the SFT.
Lift tailoring on unsteady airfoils with leading-edge vortex shedding using an inverse aerodynamic approach
Authors: Suresh Babu Arun Vishnu , Narsipur Shreyas , Gopalarathnam Ashok
Published: May 2024

In this paper, we present a physics-informed approach to tailor the lift profile of an unsteady airfoil through the execution of an appropriate maneuver. In previous research, a low-order aerodynamic model based on the unsteady thin airfoil theory was developed for predicting the flowfield and loads on airfoils undergoing arbitrary motions. The theory was phenomenologically augmented using the concept of leading edge suction parameter (LESP) to incorporate the capability to predict intermittent leading edge vortex (LEV) shedding. The criticality of LESP was used to predict the onset and termination of LEV shedding and thus model the effect of LEVs on the flowfield and loads for a prescribed motion. In the current work, an inverse aerodynamic formulation is developed based on this framework for tackling the inverse problem: to obtain the motion kinematics required for generating a prescribed lift profile for an airfoil operating in the dynamic-stall regime. The LEV-modeling capability of the aerodynamic model enables the motion-design algorithm to take into account the effect of complex phenomena, such as dynamic stall and LEV shedding, which are not taken into account in previous research approaches. Several case studies are presented to demonstrate various scenarios such as lift tracking using pitching and heaving motions, lift cancellation during unsteady motion, and the generation of a given lift profile using two equivalent motions. The kinematic profiles generated by the inverse formulation are also simulated using a high-fidelity unsteady computational fluid dynamics solver to validate the predictions.
Electrohydrodynamic deformation of a compound droplet in an alternating current and direct current superposed electric field
Authors: Mohanty Bikash , Bandopadhyay Aditya
Published: May 2024

In this study of a compound droplet subjected to alternating current (AC) and direct current (DC) superposed (AC/DC) electric fields, both core and shell deformations oscillate, albeit with reduced amplitude compared to solely alternating current electric fields. As surface tension relaxes, periodic cyclic deformation ensues, with mean deformation amplifying alongside electric field amplitude. Concurrently, normal and tangential Maxwell stresses escalate with amplitude, thus augmenting interfacial surface velocities. Manipulating the offset ratio of alternating and direct current superposed electric field modulates mean deformations. Across low frequencies, stable deformation remains constant, yet a delayed onset characterizes higher frequencies. The presence of a core affects the electrohydrodynamics of the compound droplet and shell deformation, thereby mitigating phase differences between cyclic deformations. Contrasting alternating current (AC)—only fields, alternating current and direct current superposed (AC/DC) electric field scenarios exhibit heightened surface charge densities and prompter stable deformation onset. Furthermore, the direct current component magnifies mean deformations while harmonizing phase disparities between core and shell deformations. This study illuminates the intricate interplay between alternating current and direct current fields on compound droplet behavior, offering profound insight with broad implications for applications necessitating precise deformations under electric fields.
Aerodynamics of a flapping wing with stroke deviation in forward flight
Authors: Chen Zengshuang , Xie Yuxin , Zhang Yang , Li Li , Meng Xueguang
Published: May 2024

In this paper, we numerically studied the effect of stroke deviation on the aerodynamic performance of the three-dimensional flapping wing in forward flight at a low Reynolds number. Six deviation motion patterns with different stroke deviation amplitudes were investigated. The results show that the distinct patterns exert a substantial influence on the aerodynamic forces of the flapping wing, with a more pronounced effect at higher values of deviation amplitude. For most patterns, stroke deviation enhances either lift or thrust performance unilaterally. The maximum lift and thrust of the wing with deviation motion can be 37% and 35% larger than that of the wing without deviation motion. A detailed analysis of typical flow characteristics underscores the pivotal role of deviation motion in aerodynamic force generation. Finally, two artificially created innovative deviation motion patterns are proposed, which exhibit an exceptional capacity to augment thrust by up to 123% or enhance comprehensive aerodynamic performance significantly. These findings establish a theoretical foundation for designing high-performance flapping-wing micro-air vehicles.
Flapping dynamics of a flexible membrane attached to the leading edge of a forward-facing step
Authors: Liu Zhiwei , Wang Hanfeng , Li Jiaxuan , Li Huan , Zhao Chongyu
Published: May 2024

The flapping dynamics of a flexible membrane (FM) and its effect on the flow fields over and pressure fluctuations on a forward-facing step (FFS) have been investigated experimentally. The two-dimensional FM with 40 mm in length and 0.15 mm in thickness was vertically attached to the leading edge of a FFS with 40 mm in height. The deformation of the flapping FM was recorded by a high-speed camera. Velocity data in the vertical central plane and the pressure fluctuations on the step surface were measured by planar particle image velocimetry and pressure sensors, respectively. The results demonstrate that as the dimensionless bending rigidity (γ) of the FM decreases, the FM displayed two distinct modes, i.e., the bending mode and the flapping mode. In the bending mode, the bent FM is similar to a curved barrier, which elevates the shear layer and delays the reattachment of separation flow. In the flapping mode, the amplitude of the FM increases with the decrease in γ, which in turn effects the scale of flapping-induced vortices (FIVs). In proper orthogonal decomposition analysis, the results reveal a transition in the dominant flow structure from large-scale separation to FIVs with reducing γ. The FIVs significantly affect the pressure distribution on the step surface of the FFS, and the range where the coherent contribution dominates expands with the decreasing γ.
Particle traps constructed on the insulator of conductive slip rings for surface flashover mitigation under particle adhesion
Authors: Yang Yang , Mu Haibao , Yao Yitong , Li He , Niu Guangqian , Liu Chengshan , Qian Zhiyuan
Published: May 2024

The generation of abrasive particles is an unavoidable consequence of sliding electrical contact wear in conductive slip rings (SRs). The adhesion of abrasive particles to the insulators may lead to a decrease in flashover voltage, posing a risk to satellite power transmission. In this paper, the effect of abrasive particles on flashover is first studied. Surface abrasive particles can distort the surface electric field of the dielectric, absorb scattered electrons, and then re-emit them, thereby accelerating the development and formation of secondary electron avalanches. Flashover test results indicate that surface abrasive particles lead to a significant reduction in flashover voltage. To mitigate the impact of particle adhesion on flashover, a method of constructing particle traps on the surface of insulators is proposed. The location and structural parameters of the particle trap are further optimized and determined. The flashover test results using planar dielectric samples and SR insulator samples both demonstrate that the optimized particle trap can significantly improve the flashover voltage. The dielectric maintains high electrical strength even when particles are trapped in particle traps. The physical details of the impact of particles on flashover and the effect of particle traps are analyzed utilizing an electron movement simulation, corroborating the experiment from a microscopic aspect.
Mean azimuthal flow of puff in pipe flow
Authors: Chen Cheng , Tao Jianjun , Xu Aiguo
Published: May 2024

The mean azimuthal flow of puff, a key structure of the subcritical transition in pipe flow, is studied numerically and theoretically in this Letter. It is revealed that the mean azimuthal velocities (MAVs) are governed by the least stable azimuthal modes at the far downstream and upstream, respectively. At the upstream near-wall region, the statistical period between the direction reversals of the area-averaged MAV becomes longer with the increase in the Reynolds number (Re), illustrating the same trend as the lifetime of puffs. At Re = 2300, the puff splitting is found to be inhibited when MAV is suppressed, and the facilitating mechanism of MAV on the puff splitting is explained in terms of the enhancement effect of MAV on the downstream disturbance kinetic energy: it elongates the central high-kinetic-energy region of puff, whose extended downstream part may grow further to generate a new puff.
Investigation on self-rectifying properties of Pt/HfO2/Ti with rivet-like structure based on ALD conformal technology
Authors: Wang Kexiang , Lu Jie , Xiang Zeyang , Li Ranping , Wang Zixuan , Jin Huilin , Jiang Ran
Published: May 2024

This work explores an architecture for nonvolatile resistive random-access memory (RRAM) systems. The study proposes a self-rectifying RRAM device utilizing a two-terminal 1R selector that harmonizes the gate control efficacy of transistors with the inherent simplicity of diode structures. A rivet-like HfO2-based RRAM array is meticulously constructed through atomic layer deposition (ALD), aiming to enhance device performance and retention stability. The conformal fabrication technique of ALD method is critical in achieving uniform coverage of isolation layers and precise electrode placement, which is instrumental in the fabrication of high-performance memory cells. Empirical analyses indicate significant improvements in rectification and ON/OFF ratios compared to existing RRAM models, bolstered by compatibility with established CMOS processes. It reveals that these advances are conducive to scalable, high-density memory integration, positioning the RRAM as a viable contender for future computational applications that require high efficiency and neuromorphic computing capabilities.
YdbH and YnbE form an intermembrane bridge to maintain lipid homeostasis in the outer membrane of
Escherichia coli
Authors: Kumar Sujeet , Davis Rebecca M. , Ruiz Natividad
Published: May 2024

The outer membrane (OM) of didermic gram-negative bacteria is essential for growth, maintenance of cellular integrity, and innate resistance to many antimicrobials. Its asymmetric lipid distribution, with phospholipids in the inner leaflet and lipopolysaccharides (LPS) in the outer leaflet, is required for these functions. Lpt proteins form a transenvelope bridge that transports newly synthesized LPS from the inner membrane (IM) to OM, but how the bulk of phospholipids are transported between these membranes is poorly understood. Recently, three members of the AsmA-like protein family, TamB, YhdP, and YdbH, were shown to be functionally redundant and were proposed to transport phospholipids between IM and OM in
Escherichia coli
. These proteins belong to the repeating β-groove superfamily, which includes eukaryotic lipid-transfer proteins that mediate phospholipid transport between organelles at contact sites. Here, we show that the IM-anchored YdbH protein interacts with the OM lipoprotein YnbE to form a functional protein bridge between the IM and OM in
E. coli
. Based on AlphaFold-Multimer predictions, genetic data, and in vivo site-directed cross-linking, we propose that YnbE interacts with YdbH through β-strand augmentation to extend the continuous hydrophobic β-groove of YdbH that is thought to shield acyl chains of phospholipids as they travel through the aqueous intermembrane periplasmic compartment. Our data also suggest that the periplasmic protein YdbL prevents extensive amyloid-like multimerization of YnbE in cells. We, therefore, propose that YdbL has a chaperone-like function that prevents uncontrolled runaway multimerization of YnbE to ensure the proper formation of the YdbH-YnbE intermembrane bridge.
Threshold current density for diffusion-controlled stability of electrolytic surface nanobubbles
Authors: Zhang Yixin , Zhu Xiaojue , Wood Jeffery A. , Lohse Detlef
Published: May 2024

Understanding the stability mechanism of surface micro/nanobubbles adhered to gas-evolving electrodes is essential for improving the efficiency of water electrolysis, which is known to be hindered by the bubble coverage on electrodes. Using molecular simulations, the diffusion-controlled evolution of single electrolytic nanobubbles on wettability-patterned nanoelectrodes is investigated. These nanoelectrodes feature hydrophobic islands as preferential nucleation sites and allow the growth of nanobubbles in the pinning mode. In these simulations, a threshold current density distinguishing stable nanobubbles from unstable nanobubbles is found. When the current density remains below the threshold value, nucleated nanobubbles grow to their equilibrium states, maintaining their nanoscopic size. However, for the current density above the threshold value, nanobubbles undergo unlimited growth and can eventually detach due to buoyancy. Increasing the pinning length of nanobubbles increases the degree of nanobubble instability. By connecting the current density with the local gas oversaturation, an extension of the stability theory for surface nanobubbles [Lohse and Zhang,
Phys. Rev. E
91
, 031003(R) (2015)] accurately predicts the nanobubble behavior found in molecular simulations, including equilibrium contact angles and the threshold current density. For larger systems that are not accessible to molecular simulations, continuum numerical simulations with the finite difference method combined with the immersed boundary method are performed, again demonstrating good agreement between numerics and theories.
Myxococcus xanthus
encapsulin cargo protein EncD is a flavin-binding protein with ferric reductase activity
Authors: Eren Elif , Watts Norman R. , Conway James F. , Wingfield Paul T.
Published: May 2024

Encapsulins are protein nanocompartments that regulate cellular metabolism in several bacteria and archaea.
Myxococcus xanthus
encapsulins protect the bacterial cells against oxidative stress by sequestering cytosolic iron. These encapsulins are formed by the shell protein EncA and three cargo proteins: EncB, EncC, and EncD. EncB and EncC form rotationally symmetric decamers with ferroxidase centers (FOCs) that oxidize Fe
+2
to Fe
+3
for iron storage in mineral form. However, the structure and function of the third cargo protein, EncD, have yet to be determined. Here, we report the x-ray crystal structure of EncD in complex with flavin mononucleotide. EncD forms an α-helical hairpin arranged as an antiparallel dimer, but unlike other flavin-binding proteins, it has no β-sheet, showing that EncD and its homologs represent a unique class of bacterial flavin-binding proteins. The cryo-EM structure of EncA-EncD encapsulins confirms that EncD binds to the interior of the EncA shell via its C-terminal targeting peptide. With only 100 amino acids, the EncD α-helical dimer forms the smallest flavin-binding domain observed to date. Unlike EncB and EncC, EncD lacks a FOC, and our biochemical results show that EncD instead is a NAD(P)H-dependent ferric reductase, indicating that the
M. xanthus
encapsulins act as an integrated system for iron homeostasis. Overall, this work contributes to our understanding of bacterial metabolism and could lead to the development of technologies for iron biomineralization and the production of iron-containing materials for the treatment of various diseases associated with oxidative stress.
Design rules for controlling active topological defects
Authors: Shankar Suraj , Scharrer Luca V. D. , Bowick Mark J. , Marchetti M. Cristina
Published: May 2024

Topological defects play a central role in the physics of many materials, including magnets, superconductors, and liquid crystals. In active fluids, defects become autonomous particles that spontaneously propel from internal active stresses and drive chaotic flows stirring the fluid. The intimate connection between defect textures and active flow suggests that properties of active materials can be engineered by controlling defects, but design principles for their spatiotemporal control remain elusive. Here, we propose a symmetry-based additive strategy for using elementary activity patterns, as active topological tweezers, to create, move, and braid such defects. By combining theory and simulations, we demonstrate how, at the collective level, spatial activity gradients act like electric fields which, when strong enough, induce an inverted topological polarization of defects, akin to a negative susceptibility dielectric. We harness this feature in a dynamic setting to collectively pattern and transport interacting active defects. Our work establishes an additive framework to sculpt flows and manipulate active defects in both space and time, paving the way to design programmable active and living materials for transport, memory, and logic.
Proverbs in Extended Conceptual Metaphor Theory
Authors: Kövecses Zoltán
Published: May 2024

In the chapter, I provide an account of metaphorical proverbs within the new framework of extended conceptual metaphor
theory, or ECMT, for short (Kövecses 2020). I rely especially on the multilevel and
contextualist aspects of this view. I argue that ECMT can account for why many proverbs are widespread in the world’s languages; why,
at the same time, many proverbs can also exhibit cultural differences; and why proverbs can have very specific meanings in particular
discourse situations. Finally, I show that context plays a very different role in metaphorical proverbs than in non-proverbial uses of
metaphor.
Metonymic layers in proverbs
Authors: Brdar Mario , Brdar-Szabó Rita , Zayniev Daler
Published: May 2024

Metonymy can be manifest at several levels in proverbs. In this chapter, we identify five such metonymic layers. We first
examine whole proverbs as instances of the specific-for-generic metonymy. Secondly, proverbs can be seen as
indirect speech acts in which an element of a speech act scenario can stand metonymically for the whole of the associated
illocutionary category. Proverbs can also appear in reduced form, and the part that is retained is capable of metonymically evoking
the whole. A phrase within a proverb can occasionally be interpreted as an instance of the metonymy participant for event.
Finally, a part of a proverb can receive a non-event metonymic interpretation that may even happen systematically, as in the case of
weather proverbs.
Contradiction in proverbs
Authors: Lemghari El Mustapha
Published: May 2024

Contradiction in proverbs has been noted over centuries. As a culture-specific phenomenon, contradiction is an important
research topic for Conceptual Metaphor Theory. It must be asked why given proverbs contradict. The likely answer is that they express
opposite meanings. Granted the metaphoricity of proverbs’ meanings, contradictory proverbs must be assumed to be motivated via
opposite metaphors. This hypothesis is workable, but with the proviso that the metaphorical conceptualisations concerned are not
standard conceptual metaphors but rather stereotypical metaphors – a kind of metaphors that emerge from stereotypes, that is,
stereotypical thoughts that speakers within a speech community attach to concepts.
Living is movement
Authors: Sekyi-Baidoo Yaw
Published: May 2024

Proverbs, sayings, metaphors, and symbolism represent connections between physical experiences, their cognitive
engagements and language, which becomes both a storage place and a promoter of this symbiosis. Departing from the universal life
is a journey conventional metaphor, the study examines the representation of the connection between movement and living and how
they are reflected in Akan philosophical values. Guided by Johnson’s schema theory, Lakoff and Johnson’s Conceptual Metaphor theory,
and Lakoff and Turner’s (1989) Great Chain Metaphor Theory, the study discusses the
living is movement schema and component conceptual metaphors in Akan proverbs. It also examines related orientational
metaphors including ‘success is up/away’ and security is in/within in the proverbs, linking all these cognitive
representations of movement to the Akan philosophy of ‘life and its living’.
Corpus-based Translation of Private Legal Documents
Authors: Giampieri Patrizia
Published: May 2024

Legal translation is hallmarked by peculiarities revolving around language intricacies, particular formulae, and system-specificity issues. At present, there is a spectrum of legal corpora dedicated to court-related topics and legislation, but there is no corpus composed of private legal documents such as contracts and agreements. This book wishes to bridge this gap by providing English-Italian comparable corpora related to the domain of (general) terms and conditions of service, together with a model for their use in the translation classroom. It offers a novel contribution to the scientific community as it makes corpora of private legal documents available for consultation. In addition, it shows that legal corpora built by following rigorous methods can become reliable tools in translator training and, most likely, in translation practice. This book is for students in Translation Studies, professional translators, researchers and scholars in legal language and legal translation, as well as legal practitioners and lawyers.
How does dyslexia impact second language acquisition?
Authors: Venagli Ilaria , Kupisch Tanja
Published: May 2024

This study compares the self-perception of first (L1) and second (L2) language competence and
dyslexia awareness in two groups of dyslexic students, one German and one Italian, learning English as a second
language. Based on a survey, we investigate the relationship between students’ self-perception of their L1 and L2
competence, and how perceived L1 competence, L2 learning motivation, time of dyslexia diagnosis, and typological
similarity between L1 and L2 modulate their perceived L2 competence. The findings indicate that L1 and L2
self-perception are interdependent, and that high motivation for language learning predicts better self-perception of
L2 competence. Differences emerged between the two groups’ perceived L2 competence and motivation for language
learning. Moreover, while students themselves are aware of the implications associated with dyslexia, they perceive a
lack thereof amongst their teachers and peers, leading to negative emotions, such as shame, lack of self-esteem, and
motivation to engage in foreign language learning.
Early phonological acquisition in multi-accent contexts
Authors: Sim Jasper Hong , Post Brechtje
Published: May 2024

Many children acquire the sound system of their language(s) in multi-accent environments. Yet, the
variation and inconsistencies that exist in the linguistic input to these children and the effects of variable input
on early phonological development remain relatively underexplored and underrepresented in the field of language
acquisition. This chapter provides an overview of the growing body of work that examines early phonological
acquisition in diverse contexts. It first describes the monolingual and bilingual contexts in which the phonetic and
phonological properties of adult input can be particularly variable, followed by the different types of input
variability. The implications of variable input on phonological development in children are then discussed, before
some recommendations for researching early phonological acquisition.
Diagnosing speech sound disorder in bilingual Vietnamese-English-speaking children
Authors: Margetson Kate , McLeod Sharynne , Verdon Sarah
Published: May 2024

Multilingual children suspected of having speech sound disorders (SSD) are often only assessed in
English due to challenges facing speech-language pathologists (SLPs) such as inadequate resources, lack of access to
multilingual SLPs or interpreters, and limited SLP knowledge and skill in assessing unfamiliar languages. This paper
describes the speech profiles and diagnostic decision-making for four bilingual Vietnamese-English speaking children
aged 4–6 years. When using English-only assessment all children were diagnosed with SSD. When assessed in English and
Vietnamese, only two children were diagnosed with SSD. Many mismatches could be explained by cross-linguistic transfer
and ambient phonology. These different diagnostic outcomes demonstrate that direct speech assessment in home
language(s) and English is essential for accurate diagnosis of SSD in multilingual children.
Speech and language assessment of multilingual children in Hungary
Authors: Bunta Ferenc , Fürész-Mayernik Melinda , Bóna Judit , Navracsics Judit , Bátyi Szilvia , Parapatics Andrea
Published: May 2024

For over 100 years, Hungary has consisted of predominantly Hungarian-speaking individuals with
98.9% claiming Hungarian as their native language in 2001. On the latest census in 2011, less than 7% of people living
in Hungary identified themselves as belonging to a minority ethnic group. However, in recent years, Hungary has
experienced an increase in immigrants whose home language is other than Hungarian. The educational system and
speech-language pathology practices have not caught up with the reality of having non-Hungarian-speaking immigrants
entering public schools. In this paper, we review the literature on the growing issue of how Hungarian society and its
educational system are grappling with accommodating immigrants whose home language may be other than Hungarian.
Dynamic assessment in phonology
Authors: Kehoe Margaret , Matrat Mélodie
Published: May 2024

Dynamic assessment (DA) is an approach strongly recommended for bilingual children since it
measures children’s learning capacities and not their static knowledge. It has been widely applied to the assessment
of children’s lexical, morphosyntactic, and narrative abilities but minimally so to children’s phonological abilities;
however, its application to phonology has existed for many years in the form of stimulability testing. This chapter
reviews the notion of stimulability and how it has been integrated into DA approaches to phonological production,
primarily in English. The authors describe two French DAs of phonology, which manipulate linguistic environment and
cue levels, and target structures that are late acquired in French speech sound development. The chapter presents
preliminary data on them with French-speaking monolingual and bilingual children.
A revised Natural Growth Theory of Acquisition
Authors: Dziubalska-Kołaczyk Katarzyna , Wrembel Magdalena
Published: May 2024

Different theories have been put forward to model bilingual acquisition, yet only few assume a
multilingual perspective. In this chapter, the authors aim to briefly overview relevant theoretical approaches to
L2/L3 acquisition and offer a revised version of a new framework, which can account for the complexity of the
acquisition process. In this theory, the authors want to modify and extend the explanatory potential offered by
classic natural phonology with the epistemological support from complex systems and with inductive support from the
data. The assumptions of the Natural Growth Theory of Acquisition are further developed based on principled
explanations and inductive data-driven accounts. In this contribution, selected data from studies on third language
phonology (L3 phonology) are reinterpreted for this purpose.
More than spelling accuracy
Authors: Bahr Ruth Huntley , Silliman Elaine R. , Conover Laura
Published: May 2024

Spelling is a linguistic process that integrates phonological, orthographic, and morphological
knowledge into novel word forms. Regardless of language, students learn to identify meaningful sound/letter
combinations as they learn how to spell. However, most spelling investigations only consider overall word accuracy and
not the nature and number of linguistic features in error. This chapter illustrates the utility of a linguistic
scoring procedure in documenting the nature of misspelling patterns longitudinally in two groups of students from
grades 1–7 that varied by spelling ability. Quantitative and qualitative analyses of misspellings demonstrate how
general word knowledge develops into specific word knowledge for spelling. This type of fine-grained linguistic
analysis is useful in studying spelling skill in any alphabetic or alphasyllabary language.
Phonological transfer in oral and written production among adult L2 learners of Swedish
Authors: Zetterholm Elisabeth
Published: May 2024

A foreign accent is usually inevitable among adult second language (L2) learners. The speaker’s
first language (L1) can often be identified based on transfer of linguistic features from L1 to L2. Misspellings in
texts written by adolescents in their L2 are traced to the phonology in participants L1s and explained as transfer
(Andersson, 1981). The aim of this study is to investigate whether a
relationship between oral and written production (in L2) can be found among adult L2 learners of Swedish. A dictation
exercise shows misspellings in texts that can be related to accented speech and phonology in the participants’ L1s.
Results are of interest and relevance for didactic development in the teaching of Swedish as a second language.