bluuebunny/crossref_metadata_2025 huggingface dataset:
Intermittency, bursty turbulence, and ion and electron phase-space holes formation in collisionless current-carrying plasmas
Authors: Chen Jian , Khrabrov Alexander V. , Kaganovich Igor D. , Li He-Ping
Published: April 2024

In the previous studies of nonlinear saturation of the Buneman instability caused by high electron drift velocity relative to ions, the phase-space holes and the plateau on the electron velocity distribution function were identified as features of the saturation stage of instability [notably in the paper by Omura et al., J. Geophys. Res. 108, 1197 (2003)]. We have performed a much longer simulation of the Buneman instability and observed a secondary instability. This secondary instability generates fast electron-acoustic waves. By analyzing the phase-space plot of ions and electrons, we show that the fast electron heating and the formation of the plateau of electron velocity distribution function are not due to the quasi-linear diffusion but due to the nonlinear interaction of ion- and electron-acoustic solitary waves (phase-space holes) by exchange of trapped electrons in each wave. We also report the details on the intermittent and bursty nature of turbulence driven by this instability.
Lead-free CsCu2I3 thin films prepared by one-step chemical vapor deposition method for ultraviolet photodetector
Authors: He Yi , Ou Kai , Zhang Wenting , Ni Yuxiang , Xia Yudong , Wang Hongyan
Published: April 2024

In recent years, inorganic lead-free perovskite materials have garnered attention for their non-toxicity, high carrier mobility, and strong light absorption capabilities, showing promising application prospects in photoelectric sensing. CsCu2I3 perovskite has been mentioned as one of the representatives and as a potential material for short-wavelength optoelectronic devices. This study employs a one-step chemical vapor deposition (CVD) process to fabricate CsCu2I3 thin films, which exhibit a vibrant yellow emission at 560 nm. Ultraviolet photodetectors utilizing CsCu2I3 films demonstrate an exceptional responsivity and a detectivity of 1.43 A/W and 1.15 × 1012 Jones (254 nm, 5 V bias), along with rapid response times (trise ≈ 50 ms, tdecay ≈ 70 ms). Moreover, this work examines the factors affecting device performance, including wavelength, operating voltage, and film thickness. It presents a straightforward, ecofriendly CVD method for producing lead-free perovskite films and optoelectronic devices, which has significant implications for the development of lead-free perovskite-based photoelectric technologies.
Absolute distance meter without dead zone based on free-running dual femtosecond lasers
Authors: Han Senmiao , Yang Linghui , Song Youjian , Niu Qiong , Shi Yanqing , Yu Hongyi , Hu Xinyuan , Zhu Jigui
Published: April 2024

Absolute distance measurements based on femtosecond lasers have been extensively studied for precision metrology and advanced manufacturing, with the advantages of traceability, high speed, and nanometer precision. However, in previous studies, the dual femtosecond laser ranging system showed limitations such as system complexity, lower integration, dead zone problems in single optical path detection, and high requirements for laser coherence. It is challenging to achieve a high degree of integration and large-scale continuous measurements using femtosecond lasers, ineluctably limiting practical applications in engineering fields. Here, based on the free-running dual femtosecond lasers and the nonlinear asynchronous optical sampling method, we design a highly integrated absolute distance meter. In particular, the dead zone problem is solved by the polarization multiplexing technique, and the digital control system and signal processing system are completed by the Field Programmable Gate Array (FPGA). The absolute distance meter enables rapid, continuous, and accurate measurements over a considerable range without dead zones, which paves a promising way for the integration, instrumentation, and industrial applications of femtosecond laser ranging systems.
Thermodynamics of reversible hydrogen storage: Does alkoxy-substitution of naphthalene yield functional advantages for LOHC systems?
Authors: Verevkin Sergey P. , Samarov Artemiy A. , Vostrikov Sergey V.
Published: April 2024

The reversible hydrogenation/dehydrogenation of aromatic molecules, known as liquid organic hydrogen carriers (LOHCs), is considered an attractive option for the safe storage and release of elemental hydrogen. The LOHC systems based on the alkoxy-naphthalene/alkoxy-decalin studied in this work can become potentially attractive from the point of view of the thermodynamic conditions of the reversible hydrogenation/dehydrogenation processes. This work reports the results of a complex experimental investigation of the thermochemical properties of the reactants of the LOHC systems. The enthalpies of formation were measured using high-precision combustion calorimetry, the enthalpies of vaporization and sublimation were derived from the vapor pressure–temperature dependencies measured using the transpiration method, and the melting temperatures and enthalpies of fusion were measured using the differential scanning calorimetry method. The liquid-phase enthalpies of formation of methoxy- and ethoxy-substituted naphthalenes and methoxy- and ethoxy-substituted decalins were derived and used for the thermodynamic analysis of hydrogenation/dehydrogenation reactions and transferhydrogenation reactions.
A modified weakly compressible smoothed particle hydrodynamics mixture model for accurate simulation of wave and porous structure interaction
Authors: Zhang Guibin , Tang Danling , Wen Hongjie , Chen Jianyun
Published: April 2024

In this study, a modified weakly compressible smoothed particle hydrodynamics (WCSPH) mixture model was developed to more accurately simulate the interaction between waves and porous structures. In this model, we enhanced the governing equations of the traditional WCSPH mixture model by introducing Darcy velocity, apparent density, and an adjustable smoothing length. This refinement ensures that the modified model effectively maintains the conservation of fluid volume in seepage simulations. Additionally, this paper proposes a permeable interface treatment technique that replaces traditional smoothed particle hydrodynamics interpolation with finite element shape function interpolation, significantly enhancing computational efficiency. At the same time, we also introduced and revised a particle shifting technique, which further increases the computational precision of the model. The modified WCSPH mixture model was then applied to simulate several physical experiments, including the dam-break wave propagation in a permeable dam, the attenuation of solitary waves on a permeable riverbed, the propagation of the solitary wave on a submerged porous structure, and the breaking process of waves passing through permeable breakwaters. Through comparison with the experimental data and other numerical results, the current model was comprehensively verified from various aspects, such as fluid volume conservation, wave evolution in and around the porous structure, and pressure distribution characteristics. The results confirm the excellent performance of the current model in simulating the interaction between waves and porous structures.
Effect of disturbing flow ring on hydrodynamic cavitation characteristics of self-excited oscillating cavitation used for RB degradation
Authors: Nie Songlin , Qin Tingting , Ji Hui , Ma Zhonghai , Yin Fanglong
Published: April 2024

This study developed an innovative structure known as the Disturbed flow Self-excited oscillating cavitator (DF-SEOC) to enhance cavitation performance and improve wastewater treatment efficiency. The DF-SEOC holds a distinct advantage due to its internal disturbing flow ring structure, which effectively blocks the fluid and enhances its performance. This unique design promotes multiple collisions within the cavitator, thereby significantly increasing the cavitation area. To optimize the DF-SEOC's performance, investigations into vapor volume fraction and negative pressure under different structural parameters were conducted to determine the optimal configuration. To achieve this optimization, an integration method combining computational fluid dynamics, surrogate modeling, Non-dominated Sorted Genetic Algorithm-II with Elite Strategies, and gray theory was proposed to search for the Pareto frontier solution. This comprehensive approach enabled the identification of optimal parameters for the DF-SEOC. Furthermore, the proposed optimization scheme was validated through simulation analysis and Rhodamine B degradation experiments, with a comparison against existing cavitators. The simulation results demonstrated that the optimized values of vapor volume fraction and negative pressure for the DF-SEOC increased by 9.71% and 1.71%, respectively, compared to existing cavitators. Additionally, the degradation experiments revealed that the DF-SEOC exhibited a 61.42% higher degradation capacity than existing cavitators.
Tin-oxo nanoclusters for extreme ultraviolet photoresists: Effects of ligands, counterions, and doping
Authors: Du Tingli , Yang Xiaowei , Zhao Yanyan , Han Pingping , Zhao Jijun , Zhou Si
Published: April 2024

The extreme ultraviolet (EUV) nanolithography technology is the keystone for developing the next-generation chips. As conventional chemically amplified resists are approaching the resolution limit, metal-containing photoresists, especially tin-oxo clusters, seize the opportunity to embrace this challenge owing to their small sizes, precise atomic structures, and strong EUV absorption. However, atomistic insights into the mechanism for regulating their photolithographic behavior are lacking. Herein, we systematically explored the effects of ligands, counterions, and endohedral doping on the photophysical properties of tin-oxo cage clusters by first-principles calculations combined with molecular dynamics simulations. Photoresists assembled by allyl-protected clusters with small-size OH− or Cl− counterions have a high absorption coefficient at the EUV wavelength of 13.5 nm and a low energy cost for ligand detachment and superior stability to ensure high sensitivity and strong etch resistance, respectively. The photoresist performance can further be improved by endohedral doping of the metal-oxo nanocage with Ag+ and Cd2+ ions, which exhibit superatomic characteristics and are likely to be synthesized in laboratory. These theoretical results provide useful guidance for modification of metal-oxo clusters for high-resolution EUV photolithography.
Self-assembly of chemical shakers
Authors: Qiao Liyan , Kapral Raymond
Published: April 2024

Chemical shakers are active particles with zero propulsion velocity whose activity derives from chemical reactions on portions of their surfaces. Although they do not move, except through Brownian motion, the nonequilibrium concentration and velocity fields that they generate endow them with properties that differ from their equilibrium counterparts. In particular, collections of such shakers can actively move, reorient, and self-assemble into various cluster states, which are the subject of this paper. Elongated chemical shakers constructed from linked catalytic and noncatalytic spheres are considered, and it is shown how hydrodynamic, chemotactic, and shape-dependent interactions give rise to various self-assembled shaker structures. The chemical forces responsible for cluster formation are described in terms of a model based on pair-wise additive contributions. The forms of the self-assembled structures can be varied by changing the chemostat concentrations that control the nonequilibrium state. The resulting structures and their manipulation through chemical means suggest ways to construct a class of active materials for applications.
Effect of length and attack angle of the splitter plates on circular cylinder piezoelectric water energy harvester
Authors: Shen Yu , Wang Jiasong , Wang Junlei , Zheng Hanxu , Lin Ke , Xu Haibo
Published: April 2024

With the micro-miniaturization of offshore wireless sensors, signal lights, and other devices and the emergence of the problem of self-powering in the distant sea, how to harvest energy from low-speed currents has become a hot spot of research nowadays. To improve the energy output power and conversion efficiency of low-speed water flow, we propose a vertical cantilever beam circular cylinders fitted with a rigid splitter plate piezoelectric energy harvester (CSPPEH). In this paper, the influence of the length and the attack angle of the splitter plate on CSPPEH has been experimentally investigated. The vibration response mechanism involving the mutual transition between vortex-induced vibration and galloping was analyzed through particle image velocimetry flow field visualization. The experimental results indicate that the vibration and piezoelectric characteristics of the CSPPEH increase initially and then decrease with the length of the splitter plates (L/D = 0–2.4) at the attack angle of 0°, which can be explained by the theoretical model of the energy harvester. It is found that the optimal vibration and piezoelectric characteristics occur at a rigid splitter plate length of 1.40D with an attack angle of 90°. The maximum values for amplitude, vibration swing angle, voltage, power, and power density are 4.96D, 21.7°, 42.68 V, 910.81 μW, and 1.94 mW/cm3, respectively. Efficiency was up to 2.2% at 0.4D length and 90° attack angle of the splitter plate. Compared to the bare circular cylinder energy harvester, the output power and efficiency are significantly improved. The demonstration of continuous charging and discharging of capacitors and light emitting diode lights is performed to show the practicability of the designed CSPPEH. Overall, the present study enables the applications of CSPPEH for realizing self-powered wireless sensing and signal lights under low-water-speed environments.
Numerical analysis of microchannel heat sink performance using delta vortex generator
Authors: Raj Deepak Kumar , Datta Aparesh
Published: April 2024

The design of unique microsinks arises from the desire to provide efficient cooling at low pressure drop for a more compact miniaturized electronic equipment. Three-dimensional numerical investigations of heat transfer and fluid flow have been carried out with delta vortex generator (DVG) structures in the rectangular microchannel. A pair of delta vortex generators (DVGs) are placed symmetrically about the horizontal mid plane in rectangular microchannels. Performance variances are assessed on the basis of the average Nusselt number (Nu), friction factor (f), and thermal performance (TP) along with the thermal resistance (RT) and hydraulic resistance (RH) for the Reynolds number in the range of 93 to 746. The parametric variation has been carried out by altering geometric parameters such as the angle of DVGs with centerline (θ), the number of pair of DVGs (n), the length of DVGs (l), the distance of DVGs from the centerline (B), the position of DVGs from the inlet for first pair (L1), and the distance between the vortex generators (S). The objective is kept to maximize the TP, to minimize the value of thermal resistance, and to decrease the increase in the hydraulic resistance for the same geometrical variation. The highest thermal performance equal to 1.256 has been achieved with the combination of θ, n, l, B, S, and L1 equal to 45°, 3, 0.6 mm, 0.1 mm, 4.5 mm, and 5.334 mm, respectively. For the same geometrical parameters, a minimum thermal resistance equal to 0.98 K/W and a hydraulic resistance equal to 3.234 kPa-min/ml have been attained at Re about 745.66. By minimizing the thermal and hydraulic resistance of the microchannel with DVGs, it becomes possible that heat can be more effectively transferred across the interface and the desired cooling can be achieved with less power input. The implementation of DVGs enhances intermixing through the generation of longitudinal and transverse vortices, leading to a more evenly distributed temperature across the channel. This enhancement in the heat transfer reduces the thermal resistance. Additionally, the vortices generated by DVGs modify the velocity profile, thereby decreasing the pressure drop and the hydraulic resistance. The specific impact of longitudinal vortices on the enhancement of the heat transfer through adjustments in geometric parameters is thoroughly elucidated.
Merging of TM-polarized bound states in the continuum in leaky-mode photonic lattices
Authors: Lee Sun-Goo , Kim Seong-Han , Suk Hong Kee , Lee Wook-Jae
Published: April 2024

Optical eigenstates with a high quality (Q) factor provide substantial advantages for a broad spectrum of optical devices, particularly those demanding strong light–matter interactions. Recently, it has been demonstrated that ultrahigh-Q resonances can be realized in planar photonic structures by merging multiple bound states in the continuum (BICs) in the momentum space. Photonic lattices with thin-film geometry are known to support abundant TE-polarized and TM-polarized BICs. While prior research has explored the merging of TE-polarized BICs, this paper presents analytical and numerical results concerning the merging of TM-polarized BICs in laterally periodic one-dimensional photonic lattices. As the thickness of photonic lattices increases, TM-polarized accidental BICs descend along the dispersion curves and eventually merge at the upper edge of the second stop band. Employing coupled-mode analysis, we calculate the analytical merging thickness at which multiple TM-polarized BICs come together at the second-order Γ point. We confirm the merging of TM-polarized BICs through finite-element method simulations. Our results can be beneficial for achieving ultrahigh-Q resonances through the merging of BICs.
h-BN in the making: The surface chemistry of borazine on Rh(111)
Authors: Freiberger Eva Marie , Düll Fabian , Bachmann Phiona , Steinhauer Johann , Williams Federico J. , Steinrück Hans-Peter , Papp Christian
Published: April 2024

Borazine is a well-established precursor molecule for the growth of hexagonal boron nitride (h-BN) via chemical vapor deposition on metal substrates. To understand the formation of the h-BN/Rh(111) moiré from borazine on a molecular level, we investigated the low-temperature adsorption and thermally induced on-surface reaction of borazine on Rh(111) in situ using synchrotron radiation-based high-resolution x-ray photoelectron spectroscopy (XPS), temperature-programmed XPS, and near-edge x-ray absorption fine structure measurements. We find that borazine adsorbs mainly as an intact molecule and have identified a flat-lying adsorption geometry. Borazine multilayers are observed to desorb below 200 K. Starting at about 300 K, dehydrogenation of the remaining borazine and borazine fragments takes place, and disordered boron nitride starts to grow. Above 600 K, the formation of the h-BN sets in. Finally, at 1100 K, the conversion to h-BN is complete. The h-BN formed by deposition and post-annealing was compared to the h-BN grown by an established procedure, proving the successful preparation of the desired two-dimensional material.
Improvements of readout signal integrity in mid-infrared superconducting nanowire single-photon detectors
Authors: Patel Sahil R. , Colangelo Marco , Beyer Andrew D. , Taylor Gregor G. , Allmaras Jason P. , Bumble Bruce , Wollman Emma E. , Shaw Matthew D. , Berggren Karl K. , Korzh Boris
Published: April 2024

Superconducting nanowire single-photon detectors (SNSPDs) in the mid-infrared (MIR) have the potential to open up numerous opportunities in fields such as exoplanet searches, direct dark matter detection, physical chemistry, and remote sensing. One challenge in pushing SNSPD sensitivity to the MIR is a decrease in the signal-to-noise ratio (SNR) of the readout signal, as the critical currents become increasingly smaller. We overcome this trade-off with a device architecture that employs impedance matching tapers and superconducting nanowire avalanche photodetectors to demonstrate increased SNR while maintaining saturated internal detection efficiency at 7.4 μm and approaching saturation at 10.6 μm. This work provides a platform for pushing SNSPD sensitivity to longer wavelengths while enabling the scalability to large arrays.
Water wave interaction with ice-sheet of variable geometry in the presence of uniform current
Authors: Aggarwal Akshita , Barman Koushik Kanti , Martha Subash Chandra , Tsai Chia-Cheng
Published: April 2024

We propose an asymptotic method to solve the problem of flexural-gravity wave scattering by an ice sheet of variable geometry in the presence of uniform currents. The significance of the article resides in the development of first and second-order solutions via the use of asymptotic expansion and the Fourier transform technique. We consider two different shape functions for the plate geometry, namely, Gaussian and Gaussian oscillatory. For both shape functions, the first and second-order solutions result in a major impact of depth Froude numbers in hydrodynamic coefficients, emphasizing the crucial function of the higher-order solutions in understanding the current responsiveness. We also observe the occurrence of Bragg resonance for the Gaussian oscillatory shape. The depth Froude number alters the frequency of wave components that are most reflected, and wave action conservation causes a rise in the energy of reflected waves. The depth Froude numbers can induce a unique minimum in reflection coefficient, which is close to 0. An examination of plate deflection reveals that the elevation amplitude is substantially higher near the point where there is a peak of elastic plate's shape. The pressure exerted by the plate is also concentrated near this point, highlighting the significance of the elastic plate's shape. The collective numerical observations for both shapes provide insight into resonance phenomena, the role of plate shape, and the intricate relationship between wave characteristics and varying plate properties. The findings from this study could assist geologists and marine engineers in designing and managing ice sheets, ports, and harbor infrastructure.
Experimental investigation of boundary layer transition by wall-mounted elements
Authors: Park Jongyeol , Hwang Wontae , Rhee Shin Hyung
Published: April 2024

In model tests with low Reynolds numbers (Re), wall-mounted elements are used for promoting boundary layer transition, which aims to imitate the turbulent flow around the full-scale subjects with high Reynolds numbers. Ship model test results are obtained for model-scale ship flow for Re of 105 to 106, and these results are extrapolated to full-scale ship flow for Re of 108–109. However, only global measurement data have been used to enforce a brute force approach, ignoring relaminarization, overstimulation, and parasitic drag in local flow features. To address these problems, the freestream velocity within the boundary layer around the wall-mounted elements was investigated in this study. Different size two-dimensional (2D) cylindrical rods and various configurations of an array of three-dimensional (3D) cylinders were considered. The effects of wall-mounted elements were analyzed based on the roughness Reynolds number and spanwise wavenumber, calculated based on the height in the wall normal direction and the spacing between the 3D cylinders, respectively. The range of roughness Reynolds number for promoting a transition to turbulence without overstimulation was identified as 30–118 for 2D cylindrical rods and 262–1268 for arrays of 3D cylinders.
Resonant plasmonic terahertz photomixing using interdigital graphene micro-nanoribbon arrays
Authors: Ryzhii V. , Ryzhii M. , Tang C. , Otsuji T. , Shur M. S.
Published: April 2024

We analyze the generation of the terahertz (THz) radiation in photomixers using the interdigital graphene micro-nanoribbon (GMNR) array excited by modulated light or ultrashort radiation pulses. Replacing the standard metal electrodes by the GMNR array enables in the twofold advantages: an increase in the carrier generation efficiency due to the GMNR optical transparence and the possibility of the resonant excitation of plasmonic oscillations. The latter might lead to especially strong increase in the efficiency of the conversion of the optical signals into the THz radiation if the plasmonic oscillation quality factor is reasonably large.
Modeling of memory effects in nanofluidic diodes
Authors: Cervera Javier , Portillo Sergio , Ramirez Patricio , Mafe Salvador
Published: April 2024

Nanofluidic diodes and ionic solutions find application in electrochemical circuits for information processing, controlled release, and signal conversion in hybrid devices. Here, we describe a physical model that accounts for the memory effects observed in conical nanopores in terms of the driving signal and ionic solution characteristics. The concepts invoked describe the device operation on the basis of the electrical interaction between the pore surface charges and the nanoconfined ionic solution. The physical insights provided can explain the experimental dependence of the nanofluidic tunability on the amplitude and frequency of the driving signal, the ionic concentration, and the solution pH. The model should also be useful for the design of electrochemical circuits based on ionic conduction in asymmetric memristors.
First-principles calculations of defects and electron–phonon interactions: Seminal contributions of Audrius Alkauskas to the understanding of recombination processes
Authors: Zhang Xie , Turiansky Mark E. , Razinkovas Lukas , Maciaszek Marek , Broqvist Peter , Yan Qimin , Lyons John L. , Dreyer Cyrus E. , Wickramaratne Darshana , Gali Ádám , Pasquarello Alfredo , Van de Walle Chris G.
Published: April 2024

First-principles calculations of defects and electron–phonon interactions play a critical role in the design and optimization of materials for electronic and optoelectronic devices. The late Audrius Alkauskas made seminal contributions to developing rigorous first-principles methodologies for the computation of defects and electron–phonon interactions, especially in the context of understanding the fundamental mechanisms of carrier recombination in semiconductors. Alkauskas was also a pioneer in the field of quantum defects, helping to build a first-principles understanding of the prototype nitrogen-vacancy center in diamond, as well as identifying novel defects. Here, we describe the important contributions made by Alkauskas and his collaborators and outline fruitful research directions that Alkauskas would have been keen to pursue. Audrius Alkauskas’ scientific achievements and insights highlighted in this article will inspire and guide future developments and advances in the field.
Super-bit-resolution enabled by noise-tolerant temporal single pixel imaging
Authors: Keyaki Ryota , Fukatsu Susumu
Published: April 2024

Super-bit-resolution implies the survival of data that could have been lost beyond the digitizing bit resolution. This yet unexplored ability to beat the bit threshold of output readings has been achieved by making temporal ghost imaging (TGI) virtually noiseless. To this end, acquired immunity against self-inflicting noise was granted by implementing orthogonalized illumination in one-time readout TGI as a temporal analog of single pixel imaging. The results have greater impacts on metrology and signal processing, not limited to (T)GI.
Electric field-induced nonreciprocal spin current due to chiral phonons in chiral-structure superconductors
Authors: Yao Dapeng , Matsuo Mamoru , Yokoyama Takehito
Published: April 2024

A recent experiment [Nakajima, et al., Nature 613, 479 (2023)] has reported a pair of oppositely polarized spins under an alternating electric current in a superconductor with a chiral structure. However, these behaviors cannot be explained by the conventional Edelstein effect and require a new mechanism. In this Letter, we propose a mechanism of spin current generation under an external electric field due to chiral phonons in a chiral-structure superconductor based on the Bogoliubov de Gennes and the Boltzmann equations. In our mechanism, chiral phonons are induced by electric field due to inversion symmetry breaking and electron–phonon interaction. They work as an effective Zeeman field and hence spin-polarize Bogoliubov quasiparticles in the superconductor. As a result, the spin current carried by the quasiparticles flows along the screw axis and shows a quadratic dependence on the electric field at the low-field range, leading to a nonreciprocal spin transport. The spin current also shows a nonmonotonic temperature dependence, reaching its maximum at around the superconducting transition temperature.
Particle levitation tensiometry (PLT) for probing interfaces of liquid–liquid phase separation systems (LLPSs)
Authors: Wu Diwen , Wang Siquan , Li Lei , Meng Si , Qi Cheng , Kong Tiantian , Liu Zhou
Published: April 2024

We introduce a particle levitation tensiometry to accurately quantify ultra-low interfacial tensions in liquid–liquid phase separation (LLPS) systems, crucial for understanding the structure and dynamics of membrane-less organelles in biological cells. Our technique uses non-reactive spherical microparticles to balance gravitational and interfacial forces, providing precise, repeatable, and reliable measurements across a wide range of LLPS systems, including aqueous two-phase systems, coacervates, and immiscible oil–oil systems. By adjusting the Bond number through variations in the bead size and density, our method allows for accurate interfacial tension measurements across values as low as 0.37 μN/m with minimal deviation and efficiently detects substantial variations in interfacial tensions with changes in compositions, concentrations, and ionic strengths; for instance, it recorded a change from 7.34 μN/m at a polyelectrolyte concentration of 0.002 M to 8.26 μN/m at 0.003 M. Our findings offer insights into the dynamics of LLPS and open pathways for applications in fields where accurate interfacial tension measurement is crucial, enhancing our understanding of cellular processes and enabling practical applications in drug delivery, adhesives, and coatings.
Examining the effect of moisture thresholds on post-fire water-repellent soil: a large-scale modelling approach applied to the Upper Arroyo Seco watershed, California, USA
Authors: Pradhan Nawa Raj , Floyd Ian
Published: April 2024

Background Post-fire studies show that water repellency is limited by moisture conditions, but no existing study has examined this limiting effect at a watershed scale. Aims This study aimed to identify the soil moisture threshold value at which wildfire-induced hydrophobic condition transitions back to hydrophilic condition at a watershed scale. Methods The effect of moisture thresholds on post-fire water-repellent soil and hydrological variables including infiltration, runoff volume and peak flow are examined, using the post-wildfire hydrological model of the upper Arroyo Seco watershed, California, following the August 2009 Station Fire. Key results As the moisture threshold value increased from wilting point towards field capacity, the wildfire’s impact on runoff was greatest near the wilting point, and decreased sharply as the threshold increased. The percentage error in peak flow exponentially decreased as the moisture threshold increased and the corresponding Nash–Sutcliffe efficiency increased. Soil moisture threshold values >0.2 m3/m3 were significantly less sensitive to Nash–Sutcliffe efficiency, infiltration depth and percentage error in peak flow and runoff volume. Conclusion At the soil moisture threshold value of 0.25 m3/m3, transition from hydrophobic to hydrophilic conditions occurred. Identification of this watershed-scale soil moisture threshold value allows inclusion of the wildfire-induced hydrophobic transition back to hydrophilic condition in post-fire hydrological modelling of watersheds.
Neuromorphic one-shot learning utilizing a phase-transition material
Authors: Galloni Alessandro R. , Yuan Yifan , Zhu Minning , Yu Haoming , Bisht Ravindra S. , Wu Chung-Tse Michael , Grienberger Christine , Ramanathan Shriram , Milstein Aaron D.
Published: April 2024

Design of hardware based on biological principles of neuronal computation and plasticity in the brain is a leading approach to realizing energy- and sample-efficient AI and learning machines. An important factor in selection of the hardware building blocks is the identification of candidate materials with physical properties suitable to emulate the large dynamic ranges and varied timescales of neuronal signaling. Previous work has shown that the all-or-none spiking behavior of neurons can be mimicked by threshold switches utilizing material phase transitions. Here, we demonstrate that devices based on a prototypical metal-insulator-transition material, vanadium dioxide (VO2), can be dynamically controlled to access a continuum of intermediate resistance states. Furthermore, the timescale of their intrinsic relaxation can be configured to match a range of biologically relevant timescales from milliseconds to seconds. We exploit these device properties to emulate three aspects of neuronal analog computation: fast (~1 ms) spiking in a neuronal soma compartment, slow (~100 ms) spiking in a dendritic compartment, and ultraslow (~1 s) biochemical signaling involved in temporal credit assignment for a recently discovered biological mechanism of one-shot learning. Simulations show that an artificial neural network using properties of VO2devices to control an agent navigating a spatial environment can learn an efficient path to a reward in up to fourfold fewer trials than standard methods. The phase relaxations described in our study may be engineered in a variety of materials and can be controlled by thermal, electrical, or optical stimuli, suggesting further opportunities to emulate biological learning in neuromorphic hardware.
What one genus of showy moths can say about migration, adaptation, and wing pattern
Authors: Zhang Jing , Cong Qian , Shen Jinhui , Song Leina , Hallwachs Winnie , Janzen Daniel H. , Sourakov Andrei , Grishin Nick V.
Published: April 2024

The Ornate Moth,
Utetheisa ornatrix
, has served as a model species in chemical ecology studies for decades. Like in the widely publicized stories of the Monarch and other milkweed butterflies, the Ornate Moth and its relatives are tropical insects colonizing whole continents assisted by their chemical defenses. With the recent advances in genomic techniques and evo-devo research, it is becoming a model for studies in other areas, from wing pattern development to phylogeography, from toxicology to epigenetics. We used a genomic approach to learn about
Utetheisa’s
evolution, detoxification, dispersal abilities, and wing pattern diversity. We present an evolutionary genomic analysis of the worldwide genus
Utetheisa
, then focusing on
U. ornatrix
. Our reference genome of
U. ornatrix
reveals gene duplications in the regions possibly associated with detoxification abilities, which allows them to feed on toxic food plants. Finally, comparative genomic analysis of over 100
U. ornatrix
specimens from the museum with apparent differences in wing patterns suggest the potential roles of
cortex
and
lim3
genes in wing pattern formation of Lepidoptera and the utility of museum-preserved collection specimens for wing pattern research.
Live-attenuated virus vaccine defective in RNAi suppression induces rapid protection in neonatal and adult mice lacking mature B and T cells
Authors: Chen Gang , Han Qingxia , Li Wan-Xiang , Hai Rong , Ding Shou-Wei
Published: April 2024

Global control of infectious diseases depends on the continuous development and deployment of diverse vaccination strategies. Currently available live-attenuated and killed virus vaccines typically take a week or longer to activate specific protection by the adaptive immunity. The mosquito-transmitted Nodamura virus (NoV) is attenuated in mice by mutations that prevent expression of the B2 viral suppressor of RNA interference (VSR) and consequently, drastically enhance in vivo production of the virus-targeting small-interfering RNAs. We reported recently that 2 d after immunization with live-attenuated VSR-disabled NoV (NoVΔB2), neonatal mice become fully protected against lethal NoV challenge and develop no detectable infection. Using

Rag1
−/−

mice that produce no mature B and T lymphocytes as a model, here we examined the hypothesis that adaptive immunity is dispensable for the RNAi-based protective immunity activated by NoVΔB2 immunization. We show that immunization of both neonatal and adult

Rag1
−/−

mice with live but not killed NoVΔB2 induces full protection against NoV challenge at 2 or 14 d postimmunization. Moreover, NoVΔB2-induced protective antiviral immunity is virus-specific and remains effective in adult

Rag1
−/−

mice 42 and 90 d after a single-shot immunization. We conclude that immunization with the live-attenuated VSR-disabled RNA virus vaccine activates rapid and long-lasting protective immunity against lethal challenges by a distinct mechanism independent of the adaptive immunity mediated by B and T cells. Future studies are warranted to determine whether additional animal and human viruses attenuated by VSR inactivation induce similar protective immunity in healthy and adaptive immunity-compromised individuals.
Observations on the biology of Rhabdochona kidderi texensis, a parasite of North American cichlids
Authors: Moravec F. , Huffman D.G.
Published: April 2024

An examination of a sample of benthic invertebrates collected from the Upper San Marcos River in southwestern Texas, USA in September 1999 revealed that the nymph of the ephemeropteran Tricorythodes curvatus served as natural intermediate host of the nematode Rhabdochona kidderi texensis (Nematoda: Rhabdochonidae), an intestinal parasite mainly of the Rio Grande perch (Cichlasoma cyanoguttatum) in this locality; the prevalence of the parasite's third- and fourth-stage larvae in mayflies was 6.8% with the intensity of 1–2 larvae per nymph. Live R. kidderi texensis eggs collected from nematodes recovered from C. cyanoguttatum in Texas were transported to the Czech Republic, where they were used to experimentally infect nymphs of the palaearctic mayfly species Paraleptophlebia submarginata; the development of infective third- and fourth-stage larvae in this experimental intermediate host was completed after approximately 10 days at 19°C. Infected nymphs were fed to aquarium-reared fishes, four Cichlasoma nigrofasciatum and one Oreochromis niloticus, of which only three of the former became infected. The last (fourth) moult of a male nematode was observed in C. nigrofasciatum 23 days p.i. and adult males and gravid females with not fully mature (non-embryonated) eggs in uteri on days 40 and 51 p.i. The prepatent period of R. kidderi texensis is approximately two months.
Toxocara in the mouse: a model for parasite-altered host behaviour?
Authors: Holland C.V. , Cox D.M.
Published: April 2024

The objective of this paper is to critically evaluate the significance of parasite-altered host behaviour in the Toxocara mouse model particularly in the light of the Manipulation Hypothesis. Murine behaviours were examined in both outbred and inbred strains of mice infected with different doses of Toxocara canis ova. Behaviours investigated included activity, exploration, response to novelty, anxiety, learning, memory and social behaviour. Subsequent modifications to the behaviour of infected mice were investigated with respect to dose administered and larval accumulation in the brain. There was substantial variation in the number of larvae recovered from brains of individual mice, which received similar doses of Toxocara ova. Furthermore, the numbers of larvae recovered at different doses differed significantly between an outbred and inbred strain of mouse. Alterations in infected host behaviour occurred and were related to the number of larvae recovered from the brain. For social behaviour in outbred mice, a high infection in the brain reduced levels of aggressive behaviour and increased levels of flight and defensive behaviours. In contrast, outbred mice with a low infection in the brain displayed a greater level of risk behaviour in respect of predator odour and the light/dark box compared to control or high infection mice. Post-infection, outbred mice were more immobile whereas inbred mice showed reduced immobility and increased digging and climbing. Impaired learning ability was observed in outbred mice with moderate and high levels of infection in the brain compared to control and low infection mice. Toxocara infection has an impact upon a diverse range of murine behaviours with little evidence for a specific and hence an adaptive alteration. Many of the effects on murine host behaviour by Toxocara are likely to be pathological side effects of infection rather than as a consequence of adaptive host-manipulation. Observed changes in murine behaviour may be relevant to human toxocariasis.
Dominant negative OTULIN-related autoinflammatory syndrome
Authors: Davidson Sophia , Shibata Yuri , Collard Sophie , Zheng Hongyu , Kong Klara , Sun June M. , Laohamonthonkul Pawat , Cerra Anthony , Kratina Tobias ,   CIRCA,   AADRY, Li Margaret W.Y. , Russell Carolyn , van Beek Anna , Kirk Edwin P. , Walsh Rebecca , Alqanatish Jubran , Almojali Abdullah , Alsuwairi Wafaa , Alrasheed Abdulrahman , Lalaoui Najoua , Gray Paul E. , Komander David , Masters Seth L.
Published: April 2024

OTU deubiquitinase with linear linkage specificity (OTULIN) regulates inflammation and cell death by deubiquitinating linear ubiquitin chains generated by the linear ubiquitin chain assembly complex (LUBAC). Biallelic loss-of-function mutations causes OTULIN-related autoinflammatory syndrome (ORAS), while OTULIN haploinsuffiency has not been associated with spontaneous inflammation. However, herein, we identify two patients with the heterozygous mutation p.Cys129Ser in OTULIN. Consistent with ORAS, we observed accumulation of linear ubiquitin chains, increased sensitivity to TNF-induced death, and dysregulation of inflammatory signaling in patient cells. While the C129S mutation did not affect OTULIN protein stability or binding capacity to LUBAC and linear ubiquitin chains, it did ablate OTULIN deubiquitinase activity. Loss of activity facilitated the accumulation of autoubiquitin chains on LUBAC. Altered ubiquitination of LUBAC inhibits its recruitment to the TNF receptor signaling complex, promoting TNF-induced cell death and disease pathology. By reporting the first dominant negative mutation driving ORAS, this study expands our clinical understanding of OTULIN-associated pathology.
Pressure-Tunable Large Anomalous Hall Effect in Ferromagnetic Metal LiMn6Sn6
Authors: Gao 高 Lingling 玲玲 , Lai 赖 Junwen 俊文 , Chen 陈 Dong 栋 , Pei 裴 Cuiying 翠颖 , Wang 王 Qi 琦 , Zhao 赵 Yi 毅 , Li 李 Changhua 昌华 , Cao 曹 Weizheng 渭征 , Wu 吴 Juefei 珏霏 , Chen 陈 Yulin 宇林 , Chen 陈 Xingqiu 星秋 , Sun 孙 Yan 岩 , Felser Claudia , Qi 齐 Yanpeng 彦鹏
Published: April 2024

Recently, giant intrinsic anomalous Hall effect (AHE) has been observed in the materials with kagome lattice. Here, we systematically investigate the influence of high pressure on the AHE in the ferromagnet LiMn6Sn6 with clean Mn kagome lattice. Our in situ high-pressure Raman spectroscopy indicates that the crystal structure of LiMn6Sn6 maintains a hexagonal phase under high pressures up to 8.51 GPa. The anomalous Hall conductivity (AHC)

σ

x
y

A

remains around 150 Ω−1⋅cm−1, dominated by the intrinsic mechanism. Combined with theoretical calculations, our results indicate that the stable AHE under pressure in LiMn6Sn6 originates from the robust electronic and magnetic structure.
Magneto-transport in the monolayer MoS2 material system for high-performance field-effect transistor applications
Authors: Mandia Anup Kumar , Kumar Rohit , Lee Seung-Cheol , Bhattacharjee Satadeep , Muralidharan Bhaskaran
Published: April 2024

Electronic transport in monolayer MoS2 is significantly constrained by several extrinsic factors despite showing good prospects as a transistor channel material. Our paper aims to unveil the underlying mechanisms of the electrical and magneto-transport in monolayer MoS2. In order to quantitatively interpret the magneto-transport behavior of monolayer MoS2 on different substrate materials, identify the underlying bottlenecks, and provide guidelines for subsequent improvements, we present a deep analysis of the magneto-transport properties in the diffusive limit. Our calculations are performed on suspended monolayer MoS2 and MoS2 on different substrate materials taking into account remote impurity and the intrinsic and extrinsic phonon scattering mechanisms. We calculate the crucial transport parameters such as the Hall mobility, the conductivity tensor elements, the Hall factor, and the magnetoresistance over a wide range of temperatures, carrier concentrations, and magnetic fields. The Hall factor being a key quantity for calculating the carrier concentration and drift mobility, we show that for suspended monolayer MoS2 at room temperature, the Hall factor value is around 1.43 for magnetic fields ranging from 0.001 to 1 Tesla, which deviates significantly from the usual value of unity. In contrast, the Hall factor for various substrates approaches the ideal value of unity and remains stable in response to the magnetic field and temperature. We also show that the MoS2 over an Al2O3 substrate is a good choice for the Hall effect detector. Moreover, the magnetoresistance increases with an increase in magnetic field strength for smaller magnetic fields before reaching saturation at higher magnetic fields. The presented theoretical model quantitatively captures the scaling of mobility and various magnetoresistance coefficients with temperature, carrier densities, and magnetic fields.
Antibacterial efficacy of Rumex dentatus leaf extract-enriched zinc oxide and iron doped zinc nanoparticles: a comparative study
Authors: Shakeel Sohail , Nur Omer , Sultana Kishwar , Razaq Aamir , Mustafa Elfatih
Published: April 2024

In the current investigation, zinc oxide (ZnO) nanoparticles and Fe-doped ZnO nanoparticles were sustainably synthesized utilizing an extract derived from the Rumex dentatus plant through a green synthesis approach. The Scanning electron microscope (SEM), X-ray diffraction (XRD), Energy-dispersive x-ray spectroscopy (EDX), Ultra-violet visible spectroscopy (UV–vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and Thermogravimetric analysis (TGA) techniques were used to examine the compositional, morphological, optical, and thermal properties of both samples. The doping of iron into ZnO NPs has significantly influenced their properties. The analysis firmly established that both ZnO NPs and Fe-doped ZnO NPs have hexagonal wurtzite structures and spherical shapes by XRD and SEM. The EDX analysis suggests that iron atoms have been successfully integrated into the ZnO lattice. The change in color observed during the reaction indicated the formation of nanoparticles. The UV–vis peaks at 364 nm and 314 nm confirmed the presence of ZnO NPs and Fe-doped ZnO NPs, respectively. The band gap of ZnO NPs by Fe dopant displayed a narrowing effect. This indicates that adding iron ions to ZnO NPs offers a control band gap. The thermal study TGA revealed that Fe-doped ZnO NPs remain stable when heated up to 600 °C. The antibacterial efficacy of ZnO NPs and Fe-doped ZnO NPs was evaluated against several bacterial strains. The evaluation is based on the zone of inhibition (ZOI). Both samples exhibited excellent antibacterial properties as compared to conventional pharmaceutical agents. These results suggest that synthesizing nanoparticles through plant-based methods is a promising approach to creating versatile and environmentally friendly biomedical products.