bluuebunny/crossref_metadata_2025 huggingface dataset:
Controllable nonautonomous localized waves and dynamics for a quasi-1D Gross–Pitaevskii equation in Bose–Einstein condensations with attractive interaction
Authors: Wang Haotian , Yang Hujiang , Tian Ye , Liu Wenjun
Published: May 2024

This paper investigates dynamical behaviors and controllability of some nonautonomous localized waves based on the Gross–Pitaevskii equation with attractive interatomic interactions. Our approach is a relation constructed between the Gross–Pitaevskii equation and the standard nonlinear Schrödinger equation through a new self-similarity transformation which is to convert the exact solutions of the latter to the former’s. Subsequently, one can obtain the nonautonomous breather solutions and higher-order rogue wave solutions of the Gross–Pitaevskii equation. It has been shown that the nonautonomous localized waves can be controlled by the parameters within the self-similarity transformation, rather than relying solely on the nonlinear intensity, spectral parameters, and external potential. The control mechanism can induce an unusual number of loosely bound higher-order rogue waves. The asymptotic analysis of unusual loosely bound rogue waves shows that their essence is energy transfer among rogue waves. Numerical simulations test the dynamical stability of obtained localized wave solutions, which indicate that modifying the parameters in the self-similarity transformation can improve the stability of unstable localized waves and prolong their lifespan. We numerically confirm that the rogue wave controlled by the self-similarity transformation can be reproduced from a chaotic initial background field, hence anticipating the feasibility of its experimental observation, and propose an experimental method for observing these phenomena in Bose–Einstein condensates. The method presented in this paper can help to induce and observe new stable localized waves in some physical systems.
Detection of ion cyclotron emission by using an ion cyclotron range of frequency antennas-based diagnostic system in experimental advanced superconducting tokamak
Authors: Zhang Huapeng , Liu Lunan , Zhang Wei , Sun Xuan , Zhang Xinjun , Zhu Yubao , Zhu Guanghui , Qin Chengming , Zhang Kai , Yuan Shuai , Jiang Yuhao , Guo Yaoyao , Qiu Sichun , Wang Zhengshuyan , Li Liuxin , Zhu Yongxin , Qin Weijian , Zhang Jiadong , Xu Zelin
Published: May 2024

In the experimental advanced superconducting tokamak (EAST), a novel ion cyclotron range of frequency (ICRF) antenna-based diagnostic system is designed to measure ion cyclotron emission (ICE) driven by high-energy ions. The diagnostic system includes ICRF antenna straps, a three-tune impedance matching system, a coaxial switching system, a direct current block, and a data acquisition and storage system. Using the coaxial switching system, the ICRF antenna can be switched from the heating mode to the coupling mode between two discharges. In the 2023 EAST experiment campaign, core ICE was observed using the ICRF antenna-based diagnostic system during neutron beam injection heating, and the obtained results agreed well with the signal detected by the previous high-frequency B-dot probe-based diagnostic system.
Elucidating the formation mechanisms of the parasitic channel with buffer-free GaN/Si hetero-bonding structures
Authors: Shi Hangning , Ding Jiaxin , Qin Qingcheng , Yi Ailun , Sun Jialiang , Suga Tadatomo , Yi Juemin , Wang Jianfeng , Xu Ke , Zhou Min , Huang Kai , You Tiangui , Ou Xin
Published: May 2024

Driven by the increasing demand for 5G communication, GaN radio frequency (RF) device on Si technology has been flourishing attributable to the large size, low cost, and compatibility with complementary metal–oxide–semiconductor technology. However, a significant challenge is that a high-conductance parasitic channel forms at the interface between the III-N epitaxial layers and the Si substrate, leading to severe RF loss, which has been considerably impairing both the performance and advancement of RF GaN-on-Si technologies. Despite continuing controversies concerning the physical mechanisms engendering the parasitic channel, clarification is critically needed. Standing apart from traditional studies on RF loss in III-N epilayers grown on Si, this article comprehensively investigates the bonding interface of GaN thin film and Si(100) substrate realized via direct surface activated bonding and ion-cutting technologies. It was clearly determined that substantial diffusion of gallium (Ga) atoms into the Si substrate at the bonding interface occurred even at an annealing temperature as low as 350 °C. Subsequent high-temperature post-annealing at 800 °C intensified this diffusion, activating Ga atoms to form a p-type highly conductive parasitic channel. Simultaneously, it triggered Ga atoms aggregation and incited melt-back etching within the Si substrate at the interface. Contrasting with the conventional hetero-epitaxy, this study presents a compelling view based on the bonding technique. It conclusively elucidates the physical mechanisms of the formation of the primary source of RF loss—the p-type highly conductive parasitic channel.
Half-metal Mn2GeI2 monolayer with high Curie temperature and large perpendicular magnetic anisotropy
Authors: Luo Juncheng , Zhang Xi , Lan Mu , Xiang Gang
Published: May 2024

Two-dimensional (2D) intrinsic ferromagnetic (FM) materials with high Curie temperatures (Tc), large perpendicular magnetic anisotropy (PMA), and large spin polarization are desirable for atomically thin spintronic devices. Herein, we propose a 2D intrinsic FM material Mn2GeI2 monolayer with thermodynamical stability and outstanding FM properties using first-principles calculations. Our calculations show that Mn2GeI2 monolayer is a half-metal with a spin gap of 1.76 eV, which ensures 100% spin polarization ratio at the Fermi level. Importantly, Mn2GeI2 monolayer has a large PMA energy of 2.90 meV and a high Tc of 648 K, ideal for practical applications at room temperature. Further in-depth investigation of microscopic coupling in the Mn2GeI2 monolayer reveals that the robust ferromagnetism mainly resulted from the synthetic effect of Ruderman–Kittel–Kasuya–Yosida exchange interaction between the Mn ion layers and superexchange interaction within the Mn ion layers. Our results give insights into the structure and electronic and magnetic properties of Mn2GeI2 monolayer and provide a promising candidate for 2D spintronic devices.
Presheath-like structures and effusive particle losses for biased probes at and near I–V electron saturation
Authors: Scheiner Brett
Published: May 2024

A theory for presheath-like structures near probes biased at and above the plasma potential is developed for collisionless plasmas with an electron-neutral mean free path on the order of the chamber scale. The theory predicts presheath-like perturbations to the plasma that result from the free streaming of electrons and an effusion loss process from the chamber at the electrode. For these situations, a loss-cone-like velocity distribution function for electrons is predicted where the loss angle of the depletion region corresponds to the angular size of the electrode at a specified distance. The angle of the loss cone becomes 180° at the sheath edge. In comparison with a previous collisional electron presheath model that required electrons satisfy a Bohm criterion at the sheath edge [Scheiner et al., Phys. Plasmas 22, 123520 (2015)], the present work suggests that no such condition is needed for collisionless low pressure plasmas in the ≲10 mTorr range. The theory predicts the generation of a density depletion of roughly 0.5ne and an electron velocity moment of tens of percent of the electron thermal speed by the sheath edge in a presheath with a potential drop of less than Ti/e. The range of this presheath perturbation is determined by the electrode geometry instead of the collisional mean free path. These predictions are tested against previously published particle in cell simulations and are found to be in good agreement.
Spin-wave self-imaging: Experimental and numerical demonstration of caustic and Talbot-like diffraction patterns
Authors: Makartsou Uladzislau , Gołębiewski Mateusz , Guzowska Urszula , Stognij Alexander , Gieniusz Ryszard , Krawczyk Maciej
Published: May 2024

Extending the scope of the self-imaging phenomenon, traditionally associated with linear optics, to the domain of magnonics, this study presents the experimental demonstration and numerical analysis of spin-wave (SW) self-imaging in an in-plane magnetized yttrium iron garnet film. We explore this phenomenon using a setup in which a plane SW passes through a diffraction grating, and the resulting interference pattern is detected using Brillouin light scattering. We have varied the frequencies of the source dynamic magnetic field to discern the influence of the anisotropic dispersion relation and the caustic effect on the analyzed phenomenon. We found that at low frequencies and diffraction fields, the caustics determine the interference pattern. However, at large distances from the grating, when the waves of high diffraction order and number of slits contribute to the interference pattern, the self-imaging phenomenon and Talbot-like patterns are formed. This methodological approach not only sheds light on the behavior of SW interference under different conditions but also enhances our understanding of the SW self-imaging process in both isotropic and anisotropic media.
Superconductivity with a high upper critical field in an equiatomic high-entropy alloy Sc–V–Ti–Hf–Nb
Authors: Jangid S. , Meena P. K. , Kushwaha R. K. , Srivastava S. , Manna P. , Mishra P. , Sharma S. , Singh R. P.
Published: May 2024

High-entropy alloy (HEA) superconductors have attracted significant attention due to their exceptional low-temperature mechanical and superconducting properties. We report the synthesis and thorough characterization of an equiatomic HEA superconductor with the composition Sc0.20V0.20Ti0.20Hf0.20Nb0.20, crystallizing in a body-centered cubic crystal structure (Im3m¯). Our investigation, using magnetization, transport, and heat capacity measurements, reveals the presence of weakly coupled, fully gapped superconductivity with a transition temperature of 4.17(3) K and the upper critical field exceeding the Pauli paramagnetic limit. The metallic nature, combined with a high upper critical field, positions it as a promising candidate for applications in superconducting devices.
From Liouville to Landauer: Electron transport and the bath assumptions made along the way
Authors: Bialas David , Jorn Ryan
Published: May 2024

A generalized quantum master equation approach is introduced to describe electron transfer in molecular junctions that spans both the off-resonant (tunneling) and resonant (hopping) transport regimes. The model builds on prior insights from scattering theory but is not limited to a certain parameter range with regard to the strength of the molecule–electrode coupling. The framework is used to study the simplest case of energy and charge transfer between the molecule and the electrodes for a single site noninteracting Anderson model in the limit of symmetric and asymmetric coupling between the molecule and the electrodes. In the limit of elastic transport, the Landauer result is recovered for the current by invoking a single active electron Ansatz and a binary collision approximation for the memory kernel. Inelastic transport is considered by allowing the excitation of electron–hole pairs in the electrodes in tandem with charge transport. In the case of low bias voltages where the Fermi levels of the electrodes remain below the molecular state, it is shown that the current arises from tunneling and the molecule remains neutral. However, once the threshold is reached for aligning the fermi level of one electrode with the molecular orbital, a small amount of charge transfer occurs with a negligible amount of hopping current. While inelasticity in the current has a minimal impact on the shape of the current–voltage curve in the case of symmetric electrode coupling, the results for a slight asymmetry in coupling demonstrate complete charge transfer and a significant drop in current. These results provide encouraging confirmation that the framework can describe charge transport across a wide range of electrode–molecule coupling and provide a unique perspective for developing new master equation treatments for energy and charge transport in molecular junctions. An extension of this work to account for inelastic scattering from electron–vibrational coupling at the molecule is straightforward and will be the subject of subsequent work.
Self-starting and performance improvement of a Darrieus type wind turbine using the plasma actuator
Authors: Zare Chavoshi Majid , Ebrahimi Abbas
Published: May 2024

Although the popularity of Darrieus-type vertical axis wind turbines is growing for small-scale electricity generation, these turbines have severe challenges in self-starting. This paper proposes a flow control method, namely, the plasma actuator, to solve the self-starting problem besides enhancing the turbine performance. The Darrieus turbine is numerically investigated using a pressure-based finite volume method to solve the unsteady Reynolds-averaged Navier–Stokes and the γ–Reθt transitional model equations. Simulation of the blade rotation is performed using the sliding mesh technique accompanied by the turbine equation of motion to enable the blade rotational degree of freedom. Furthermore, the body forces associated with the plasma actuator are determined by calibrating the Shyy plasma model parameters. The plasma actuator is assessed at both the constant and free rotational speeds. The constant rotational speed results in plasma off condition show negative torque generation for tip speed ratios lower than 1.5, known as the origin of turbine self-starting challenges. The plasma actuator improves the negative torque by 128% in the tip speed ratio of 0.5 and turns it positive. Also, at larger tip speed ratios, it reduces the negative torque generation and enhances the turbine power production by up to 260%. Furthermore, the plasma actuator in free rotational speed improves the tip speed ratio increment by up to 8%, reducing the total time of turbine self-starting.
Inerter-controlled topological interface states in locally resonant lattices with beyond-nearest neighbor coupling
Authors: Cajić Milan , Karličić Danilo , Adhikari Sondipon
Published: May 2024

This paper explores the emergence of topological interface states in one-dimensional locally resonant lattices incorporating inerters in both nearest neighbor (NN) and beyond-nearest neighbor (BNN) coupling. The investigation focuses on the unique wave propagation characteristics of these lattices, particularly the presence and behavior of interface states. The non-trivial topological behavior due to broken inversion symmetry within the unit cell of the locally resonant lattice is comprehensively investigated in the presence of inerters in NN and BNN coupling. The emerging interface states in the supercell analysis exhibit specific spatial and frequency localization properties due to inerter-based BNN interactions. Additionally, the study demonstrates the ability of inerter elements with weak inertance to control the frequency of interface states while maintaining the fundamental topological properties of the lattice. The identified topological interface states in lattices with BNN coupling present an opportunity for designing diverse devices, such as waveguides, filters, sensors, and energy harvesting systems. Overall, this research enhances our comprehension of topological phenomena in inerter-based locally resonant lattices with BNN interactions and introduces possibilities for creating robust and versatile devices based on topologically protected edge/interface states.
Characteristics and mechanism of the shift in condition- and time-dependent spray patterns induced by oxygenated fuel addition
Authors: Zhang Huidong , Liu Wenchuan , Lu Yiyu , Tang Jiren
Published: May 2024

As renewable energy sources, ethanol and butanol are usually added to fuels to reduce the fossil fuel consumption and soot emissions. Gasoline direct injection with multi-hole injectors provides accurate plume control, enabling ejection toward the desired location, while spray pattern shift leads to deviation in the injection direction. The spray shift needs to be modulated to realize the desired spray pattern, which is complicated by oxygenated fuel addition. To illustrate the shift induced by oxygenated fuel addition, numerical simulations and experimental studies were performed. The macroscopic and microscopic characteristics of the spray under various operating conditions were obtained via the diffuse backlight illumination and phase Doppler anemometry methods and the simulation of the internal three-phase flow. Moreover, typical single-component and binary fuels were employed to define the general envelope of the multi-component nature for auxiliary analysis. The shift in condition- and time-dependent spray patterns under both flashing and non-flashing conditions were illustrated. The spray morphologies were characterized by rectangular- and trapezoid-like trends. The addition of oxygenated fuels resulted in a smoother trend due to the change of the vapor pressure and surface tension of the mixed fuel. Moreover, it resulted in the variation of the critical width, which is crucial for the spray pattern shift. Additionally, the correlation between the critical width and ambient pressure was obtained. For the non-flashing spray, the internal flow and jet instabilities both influenced the spray width, and the correlation between gas ingestion and turbulence characteristics was obtained. This study aimed to provide guidance for better utilization of oxygenated fuels.
Enhancement of electromechanical response in curved antiferroelectric AgNbO3 ceramics by flexoelectric effect
Authors: Zhang Liqiang , He Xiang , Zheng Zewei , Wang Lu , Chen Chen , Yi Zhiguo
Published: May 2024

AgNbO3 is a typical antiferroelectric ceramic with weak ferroelectricity at room temperature. Due to this feature, AgNbO3 has received a lot of attention in electromechanical applications, but most of these studies have focused on the doping of other elements in AgNbO3. In this study, curved AgNbO3 ceramics were fabricated using a gravity-driven annealing process, and the field-induced strains were investigated. The curved ceramic exhibited a significantly higher field-induced nominal strain compared to a flat ceramic. Experimental results revealed that the curved AgNbO3 sample exhibited a maximum nominal strain of 1.22%, significantly surpassing the theoretical value of 0.13%. Analysis of various characterizations confirmed the presence of flexoelectricity, and flexoelectricity played an important role in the ultrahigh electromechanical response of curved AgNbO3 ceramics. Additionally, we demonstrated that curved AgNbO3 ceramics can enhance the flexoelectric coefficient. These findings suggest that curved antiferroelectric ceramics can enhance their displacement output, meeting the requirements for applications in large-strain actuators.
The key role of methylenediammonium and tetrahydrotriazinium in the phase stability of FAPbI3
Authors: Feng Xiangxiang , Li Yunhao , Long Mengqiu , Cai Mengqiu , Liu Biao , Yang Junliang
Published: May 2024

Formamidinium lead triiodide (FAPbI3) is the prime candidate for single-junction perovskite solar cells, despite the metastability of the phase. To improve its ambient-phase stability and produce world-record photoelectric conversion efficiencies, methylenediammonium (MDA) has been used as an additive in FAPbI3. However, the exact function and role of MDA are still uncertain. The MDA doping may exist in the perovskite lattice in either the original structure or the THTZ-H (tetrahydrotriazinium) structure. In this research, the effects of the MDA and THTZ-H doping FAPbI3 perovskite on its stability are explored by first-principles calculations. Both MDA and THTZ-H doping can improve the stability of FAPbI3 perovskite from a structural perspective due to lattice strain and stronger H–I bonds. However, the doping mechanisms differ significantly in terms of electronic properties. The MDA doping acts by the traditional passivation mechanism. It can eliminate the iodine interstitial defect states that trap charge carriers and inhibit iodine interstitial defect migration. The THTZ-H cation can directly contribute to the band edge construction in the FAPbI3 bulk. Electron delocalization in the π-conjugated ring structure lowered the frontier orbital separation of the THTZ-H organic molecule and enabled orbital overlap with the inorganic moiety. The in-depth understanding of the mechanism of improving stability in this study would facilitate the application of FAPbI3 perovskite optoelectronic devices.
ℏ
4 quantum corrections to semiclassical transmission probabilities
Authors: Pollak Eli , Upadhyayula Sameernandan
Published: May 2024

The combination of vibrational perturbation theory with the replacement of the harmonic oscillator quantization condition along the reaction coordinate with an imaginary action to be used in the uniform semiclassical approximation for the transmission probability has been shown in recent years to be a practical method for obtaining thermal reaction rates. To date, this theory has been developed systematically only up to second order in perturbation theory. Although it gives the correct leading order term in an ℏ2 expansion, its accuracy at lower temperatures, where tunneling becomes important, is not clear. In this paper, we develop the theory to fourth order in the action. This demands developing the quantum perturbation theory up to sixth order. Remarkably, we find that the fourth order theory gives the correct ℏ4 term in the expansion of the exact thermal rate. The relative magnitude of the fourth order correction as compared to the second order term objectively indicates the accuracy of the second order theory. We also extend the previous modified second order theory to the fourth order case, creating an ℏ2 modified potential for this purpose. The resulting theory is tested on the standard examples—symmetric and asymmetric Eckart potentials and a Gaussian potential. The modified fourth order theory is remarkably accurate for the asymmetric Eckart potential.
Can Generative AI improve social science?
Authors: Bail Christopher A.
Published: May 2024

Generative AI that can produce realistic text, images, and other human-like outputs is currently transforming many different industries. Yet it is not yet known how such tools might influence social science research. I argue Generative AI has the potential to improve survey research, online experiments, automated content analyses, agent-based models, and other techniques commonly used to study human behavior. In the second section of this article, I discuss the many limitations of Generative AI. I examine how bias in the data used to train these tools can negatively impact social science research—as well as a range of other challenges related to ethics, replication, environmental impact, and the proliferation of low-quality research. I conclude by arguing that social scientists can address many of these limitations by creating open-source infrastructure for research on human behavior. Such infrastructure is not only necessary to ensure broad access to high-quality research tools, I argue, but also because the progress of AI will require deeper understanding of the social forces that guide human behavior.
Copper(II) coordination to the intrinsically disordered region of SARS-CoV-2 Nsp1
Authors: Morales Maryann , Yang Moon Young , Goddard William A. , Gray Harry B. , Winkler Jay R.
Published: May 2024

The intrinsically disordered C-terminal peptide region of severe acute respiratory syndrome coronavirus 2 nonstructural protein-1 (Nsp1-CT) inhibits host protein synthesis by blocking messenger RNA (mRNA) access to the 40S ribosome entrance tunnel. Aqueous copper(II) ions bind to the disordered peptide with micromolar affinity, creating a possible strategy to restore protein synthesis during host infection. Electron paramagnetic resonance (EPR) and tryptophan fluorescence measurements on a 10-residue model of the disordered protein region (Nsp1-CT
10
), combined with advanced quantum mechanics calculations, suggest that the peptide binds to copper(II) as a multidentate ligand. Two optimized computational models of the copper(II)-peptide complexes were derived: One corresponding to pH 6.5 and the other describing the complex at pH 7.5 to 8.5. Simulated EPR spectra based on the calculated model structures are in good agreement with experimental spectra.
Modeling and reduction of high frequency scatter noise at LIGO Livingston
Authors: Soni Siddharth , Glanzer Jane , Effler Anamaria , Frolov Valera , González Gabriela , Pele Arnaud , Schofield Robert
Published: May 2024

The sensitivity of aLIGO detectors is adversely affected by the presence of noise caused by light scattering. Low frequency seismic disturbances can create higher frequency scattering noise adversely impacting the frequency band in which we detect gravitational waves. In this paper, we analyze instances of a type of scattered light noise we call ‘Fast Scatter’ that is produced by motion at frequencies greater than 1 Hz, to locate surfaces in the detector that may be responsible for the noise. We model the phase noise to better understand the relationship between increases in seismic noise near the site and the resulting Fast Scatter observed. We find that mechanical damping of the arm cavity baffles led to a significant reduction of this noise in recent data. For a similar degree of seismic motion in the 1–

3
 

Hz

range, the rate of noise transients is reduced by a factor of ~50.
E. Coli inactivation by humidified air barrier discharge plasmas and the chemical stability of amino acids
Authors: Wang Zhishang , Liang Xinlei , Dou Di , Wang Yiming , Wu Jiang , Ni Weiyuan , Zhang Tao , Yang Dong , Meng Xiangyu , Liu Dongping
Published: May 2024

In this study, we use atmospheric air dielectric barrier discharge (DBD) plasma to inactivate E. coli (E. coli) by changing the air humidity levels. In order to analyze the inactivation process of E. coli during the humidified air DBD plasma treatment, we analyze the byproducts of 12 representational amino acids and compare their chemical stability. The experimental results show that the E. coli surface density (CFU cm−2) on a steel disc decreased significantly when the air humidity was increased from 20% to 60%, and humidified air DBD plasma at 60% humidity is very effective in inactivating E. coli. A consistently potent deactivation effect on E. coli can be seen in plasma afterglow treatment experiments over a storage time of two minutes, indicating that plasma-activated long-lived reactive oxygen and nitrogen species play a crucial role in controlling the E. coli inactivation. Compared to the low humidity (20%) condition, the concentration of reactive species produced by the plasma at high humidity (60%) increased 2-fold for 2-hydroxyterephthalic acid and 5-fold for hydrogen peroxide while ozone production was halved. Amino acid experiments showed that amino acids may be oxidized, hydroxylated and nitroxylated by reactive species. The reduction of amino acids by air DBD plasma was even more pronounced at high air humidity compared to low air humidity. Our analysis indicates that the significant inactivation of E. coli by humified air DBD plasma is related to the chemical instability of amino acids.
Medical staff dose estimation during pediatric cardiac interventional procedures
Authors: Roberto Maryanna Regina , Leite Luiz M A , Cruz Arícia R P , Khoury Helen , de Barros Vinícius S M , Neves Juliana R , Cartaxo Jéssica M , Ubeda Carlos , Asfora Viviane K
Published: May 2024

The purpose of this study is to evaluate the occupational doses (eye lens, extremities and whole body) in paediatric cardiac interventional and diagnostic catheterization procedures performed in a paediatric reference hospital located in Recife, Pernambuco. For eye lens dosimetry, the results show that the left eye receives a higher dose than the right eye, and there is a small difference between the doses received during diagnostic (D) and therapeutic (T) procedures. The extrapolated annual values for the most exposed eye are close to the annual limit. For doses to the hands, it was observed that in a significant number of procedures (37 out of 45 therapeutic procedures, or 82%) at least one hand of the physician was exposed to the primary beam. During diagnostic procedures, the physician’s hand was in the radiation field in 11 of the 17 catheterization procedures (65%). This resulted in a 10-fold increase in dose to the hands. The results underscore the need for optimization of radiation safety and continued efforts to engage staff in a radiation safety culture.
A meta transfer learning method for gearbox fault diagnosis with limited data
Authors: She Daoming , Yang Zhichao , Duan Yudan , Yan Xiaoan , Chen Jin , Li Yaoming
Published: May 2024

Intelligent diagnosis of mechanical faults is an important means to guarantee the safe maintenance of equipment. Cross domain diagnosis may lack sufficient measurement data as support, and this bottleneck is particularly prominent in high-end manufacturing. This paper presents a few-shot fault diagnosis methodology based on meta transfer learning for gearbox. To be specific, firstly, the subtasks for transfer diagnosis are constructed, and then joint distribution adaptation is conducted to align the two domain distributions; secondly, through adaptive manifold regularization, the data of target working condition is further utilized to explore the potential geometric structure of the data distribution. Meta stochastic gradient descent is explored to dynamically adjust the model’s parameter based on the obtained task information to obtain better generalization performance, ultimately to achieve transfer diagnosis of gearbox faults with few samples. The effectiveness of the approach is supported by the experimental datasets of the gearbox.
A mechanical manipulated electromechanical coupling design with stretchable electret film: mechanical sensing, energy harvesting, and actuation
Authors: Tian Zheng , Li Yifan , Li Yanyu , Han Wenwen , Ji Hui , Zhang Shuwen , Xu Minglong
Published: May 2024

Electrical and mechanical energy converts around the nature, and electromechanical coupling effect is applied in various conditions such as mechanical sensing, electrical actuation, and self-powering. During the energy type conversion, electromechanical parameters are among the key issues, such as enlarging the sensitivity and range of mechanical sensing, and energy harvesting efficiency. In this work, a mechanical manipulated approach with stretchable electret is proposed to continuously manipulate the electromechanical parameters. An electromechanical coupling demonstration with pre-stretched electret films and non-contact electrodes are applied, verifying high and regulable electromechanical coupling parameters, and it is advantaged from large deformable and overload permissible capability. This mechanical manipulation approach proposes a new possibility on simplifying the structural and mechanical design of various electromechanical devices, and further enhancing the general applicability with certain geometry and material with ultra-high and tunable electromechanical coupling parameters.
Fröhlich resonance splitting in hybrid GaN nanowire-Ag nanoparticle structures
Authors: Pozina Galia , Girshova Elizaveta I , Abrikossova Natalia , Hemmingsson Carl , Lähderanta Erkki , Kaliteevski Mikhail
Published: May 2024

Plasmonic nanoparticles (NPs) have attracted significant attention due to their unique optical properties and broad optoelectronic and photonic applications. We investigate modifications of emission in hybrid structures formed by 60 nm silver NPs and GaN planar nanowires (NWs). Bare GaN NWs exhibit photoluminescence (PL) spectra dominated by broad bands peaking at ∼3.44 eV and ∼3.33 eV, attributed to basal plane stacking faults. In hybrids, two new narrow PL lines appear at 3.36 and 3.31 eV, resulting in PL enhancement at these energies. While the 3.36 eV line in hybrid structures can be explained using the Fröhlich resonance approximation based on the electric dipole concept, the appearance of two features at 3.36 and 3.31 eV indicates the splitting of resonance lines. This phenomenon is explained in framework of theoretical model based on the interaction of the dipole with its charge image, taking into account the quadrupole moment of the silver sphere and the quadrupole field of the charge image. A good agreement is obtained between the calculated Fröhlich resonance frequencies and the experimental PL lines in hybrid structures.
Quantum control of classical motion: piston dynamics in a Rabi-coupled Bose–Einstein condensate
Authors: Li Jing , Sherman E Ya , Ruschhaupt Andreas
Published: May 2024

We develop a model and explore the dynamics of a hybrid classical-quantum system consisting of a classical piston and a self-interacting pseudospin 1/2 Bose–Einstein condensate with a time-dependent Rabi coupling. We investigate the mechanical work produced by the piston moving as a result of the quantum pressure of the condensate. The time-dependent Rabi field redistributes the condensate density between the spin components and, as a result, causes a time-dependent pressure acting on the piston. Correspondingly, the motion of the piston produces quantum evolution of the condensate mass- and spin density profiles. We show how by optimised design of the time-dependent direction of the Rabi field based on a quasi-stationary quantum pressure approximation, one can control both the position and velocity of the piston.
Manipulation of band gap in 1T-TiSe2 via rubidium deposition
Authors: Ou 欧 Yi 仪 , Chen 陈 Lei 磊 , Xin 信 Zi-Ming 子鸣 , Ren 任 Yu-Jing 宇靖 , Yuan 袁 Peng-Hao 鹏浩 , Wang 王 Zheng-Guo 政国 , Zhu 朱 Yu 玉 , Chen 陈 Jing-Zhi 景芝 , Zhang 张 Yan 焱
Published: May 2024

The 1T-TiSe2 is a two-dimensional charge-density-wave (CDW) material that attracts great interest. A small band gap locates at the Fermi level separating the Ti d-bands and Se p-bands, which makes 1T-TiSe2 a promising candidate for realizing excitonic condensation. Here, we studied the band gap in 1T-TiSe2 using angle-resolved photoemission spectroscopy (ARPES). Instead of only focusing on the in-plane band dispersions, we obtained the detailed band dispersions of both conduction and valance bands along the out-of-plane direction. We found that the conduction and valance bands split into multiple sub-bands in the CDW state due to band folding. As a result, the band gap between the Ti d-bands and Se p-bands reduces to ∼25 meV and becomes a direct gap in the CDW state. More intriguingly, such band gap can be further reduced by the rubidium deposition. The band structure becomes semimetallic in the rubidium-doped sample. Meanwhile, exotic gapless behaviors were observed at the p–d band crossing. Our result characterized the band gap of 1T-TiSe2 in three-dimensional Brillouin zone with unpreceded precision. It also suggests a closing of band gap or a potential band inversion in 1T-TiSe2 driven by rubidium deposition.
Iterative reconstruction methods and the resolution principle for fast-ion loss detector measurements
Authors: S. Schmidt Bo , Galdon-Quíroga Joaquín , Rueda-Rueda José , Poley-Sanjuán Jesús , García-Muñoz Manuel , Järleblad Henrik , C.G. Reman Bernard , Rud Mads , Valentini Andrea , Salewski Mirko , Upgrade Team the ASDEX , Tokamak Exploitation Team the EUROfusion
Published: May 2024

Fast-ion loss detectors (FILDs) are crucial for analyzing fast-ion dynamics in magnetically confined fusion plasmas. A core challenge is to derive an accurate ion velocity distribution, requiring treatment of thousands of remapped camera frames for a full discharge. The ill-posed nature of this task necessitates regularization with a well-chosen regularization parameter and computationally efficient methods. In this work, we introduce the ‘resolution principle,’ a novel criterion for selecting the optimal regularization parameter, providing a distinction between genuine features and artefacts smaller than the diagnostic resolution in the reconstruction, thereby preventing misinterpretations. This principle, coupled with three iterative reconstruction techniques—Kaczmarz’s method, coordinate descent, and Cimmino’s method—demonstrates enhanced reconstruction capabilities compared to conventional methods like Tikhonov regularization. Utilizing these techniques allows rapid processing of measurements from full discharges, removing the computational bottleneck and facilitating between-discharge reconstructions. By reconstructing 6000 camera frames from an ELMy H-mode discharge at ASDEX Upgrade, we capture the temporal evolution of gyroradii and pitch angles, unveiling a direct correlation between pitch-angle behavior and changes in the toroidal magnetic field for a specific subset of lost ions accelerated by edge-localized modes (ELMs) to energies approximately twice that of the injection energy.
A computer vision approach for satellite-driven wind nowcasting over complex terrains
Authors: Alves Décio , Mendonça Fábio , Mostafa Sheikh Shanawaz , Morgado-Dias Fernando
Published: May 2024

Accurate wind speed and direction nowcasting in regions with complex terrains remains a challenge, and critical for applications like aviation. This study proposes a new methodology by harnessing Convolutional Neural Networks and Long Short-Term Memory models with satellite imagery to address wind predictions in a complex terrain, centered on Madeira International Airport, Portugal, using satellite data as input. Results demonstrated adeptness in capturing wind transitions, pinpointing shifts up to two hours ahead, with errors of 1.74 m s−1 and 30.98° for wind speed and direction, respectively. Highlighting its aptitude in capturing the intricate atmospheric dynamics of such areas, the study reinforces the viability of computer vision for remote sites where conventional monitoring is either inefficient or expensive. With the widespread availability of satellite imagery and extensive satellite coverage, this method presents a scalable approach for worldwide applications.
Introduction
Authors: Williams Abiodun
Published: May 2024

On December 17, 1996, the General Assembly of the United Nations (UN) appointed Kofi Annan as the seventh Secretary-General of the UN. He was the first black African and the first UN staff member to lead the organization. Of the Secretaries-General of the UN, Annan was the best prepared and, in his impact on the organization, the most transformational. Annan’s global leadership cut across all his roles, including as a diplomat, mediator, administrator, and norm entrepreneur. While his contributions necessarily reflected his time in office, his values, personality, and experiences also shaped the content and style of his Secretary-Generalship. The decade from 1997 to 2006 during which he led the UN was defined by globalization. Globalization was making collective responses to global problems more necessary though not automatically easier to achieve. Annan’s tenure coincided with the “unipolar moment” during which world affairs were dominated by a single superpower, the US. Therefore, managing US–UN relations was critically important. But he had to work with the US while not alienating the other UN members. Annan was an internationalist who sought to strengthen the rules, norms, and system of global cooperation. He believed that the UN had a vital role to play in finding solutions to the problems facing humanity.
Parsnp 2.0: scalable core-genome alignment for massive microbial datasets
Authors: Kille Bryce , Nute Michael G , Huang Victor , Kim Eddie , Phillippy Adam M , Treangen Todd J
Published: May 2024

Motivation

Since 2016, the number of microbial species with available reference genomes in NCBI has more than tripled. Multiple genome alignment, the process of identifying nucleotides across multiple genomes which share a common ancestor, is used as the input to numerous downstream comparative analysis methods. Parsnp is one of the few multiple genome alignment methods able to scale to the current era of genomic data; however, there has been no major release since its initial release in 2014.

Results

To address this gap, we developed Parsnp v2, which significantly improves on its original release. Parsnp v2 provides users with more control over executions of the program, allowing Parsnp to be better tailored for different use-cases. We introduce a partitioning option to Parsnp, which allows the input to be broken up into multiple parallel alignment processes which are then combined into a final alignment. The partitioning option can reduce memory usage by over 4× and reduce runtime by over 2×, all while maintaining a precise core-genome alignment. The partitioning workflow is also less susceptible to complications caused by assembly artifacts and minor variation, as alignment anchors only need to be conserved within their partition and not across the entire input set. We highlight the performance on datasets involving thousands of bacterial and viral genomes.

Availability and implementation

Parsnp v2 is available at https://github.com/marbl/parsnp.
Updated European guidelines for clinical management of familial adenomatous polyposis (FAP), MUTYH-associated polyposis (MAP), gastric adenocarcinoma, proximal polyposis of the stomach (GAPPS) and other rare adenomatous polyposis syndromes: a joint EHTG-ESCP revision
Authors: Zaffaroni Gloria , Mannucci Alessandro , Koskenvuo Laura , de Lacy Borja , Maffioli Anna , Bisseling Tanya , Half Elizabeth , Cavestro Giulia Martina , Valle Laura , Ryan Neil , Aretz Stefan , Brown Karen , Buttitta Francesco , Carneiro Fatima , Claber Oonagh , Blanco-Colino Ruth , Collard Maxime , Crosbie Emma , Cunha Miguel , Doulias Triantafyllos , Fleming Christina , Heinrich Henriette , Hüneburg Robert , Metras Julie , Nagtegaal Iris , Negoi Ionut , Nielsen Maartje , Pellino Gianluca , Ricciardiello Luigi , Sagir Abdurrahman , Sánchez-Guillén Luis , Seppälä Toni T , Siersema Peter , Striebeck Benedikt , Sampson Julian R , Latchford Andrew , Parc Yann , Burn John , Möslein Gabriela
Published: May 2024

Background

Hereditary adenomatous polyposis syndromes, including familial adenomatous polyposis and other rare adenomatous polyposis syndromes, increase the lifetime risk of colorectal and other cancers.

Methods

A team of 38 experts convened to update the 2008 European recommendations for the clinical management of patients with adenomatous polyposis syndromes. Additionally, other rare monogenic adenomatous polyposis syndromes were reviewed and added. Eighty-nine clinically relevant questions were answered after a systematic review of the existing literature with grading of the evidence according to Grading of Recommendations, Assessment, Development, and Evaluation methodology. Two levels of consensus were identified: consensus threshold (≥67% of voting guideline committee members voting either ‘Strongly agree’ or ‘Agree’ during the Delphi rounds) and high threshold (consensus ≥ 80%).

Results

One hundred and forty statements reached a high level of consensus concerning the management of hereditary adenomatous polyposis syndromes.

Conclusion

These updated guidelines provide current, comprehensive, and evidence-based practical recommendations for the management of surveillance and treatment of familial adenomatous polyposis patients, encompassing additionally MUTYH-associated polyposis, gastric adenocarcinoma and proximal polyposis of the stomach and other recently identified polyposis syndromes based on pathogenic variants in other genes than APC or MUTYH. Due to the rarity of these diseases, patients should be managed at specialized centres.
Pathological response to neoadjuvant chemoradiotherapy for oesophageal squamous cell carcinoma in Eastern versus Western countries: meta-analysis
Authors: Gao Xing , Overtoom Hidde C G , Eyck Ben M , Huang Shi-Han , Nieboer Daan , van der Sluis Pieter C , Lagarde Sjoerd M , Wijnhoven Bas P L , Chao Yin-Kai , van Lanschot Jan J B
Published: May 2024

Objective

Locally advanced oesophageal squamous cell carcinoma can be treated with neoadjuvant chemoradiotherapy or chemotherapy followed by oesophagectomy. Discrepancies in pathological response rates have been reported between studies from Eastern versus Western countries. The aim of this study was to compare the pathological response to neoadjuvant chemoradiotherapy in Eastern versus Western countries.

Methods

Databases were searched until November 2022 for studies reporting pCR rates after neoadjuvant chemoradiotherapy for oesophageal squamous cell carcinoma. Multi-level meta-analyses were performed to pool pCR rates separately for cohorts from studies performed in centres in the Sinosphere (East) or in Europe and the Anglosphere (West).

Results

For neoadjuvant chemoradiotherapy, 51 Eastern cohorts (5636 patients) and 20 Western cohorts (3039 patients) were included. Studies from Eastern countries included more men, younger patients, more proximal tumours, and more cT4 and cN+ disease. Patients in the West were more often treated with high-dose radiotherapy, whereas patients in the East were more often treated with a platinum + fluoropyrimidine regimen. The pooled pCR rate after neoadjuvant chemoradiotherapy was 31.7% (95% c.i. 29.5% to 34.1%) in Eastern cohorts versus 40.4% (95% c.i. 35.0% to 45.9%) in Western cohorts (fixed-effect P = 0.003). For cohorts with similar cTNM stages, pooled pCR rates for the East and the West were 32.5% and 41.9% respectively (fixed-effect P = 0.003).

Conclusion

The pathological response to neoadjuvant chemoradiotherapy is less favourable in patients treated in Eastern countries compared with Western countries. Despite efforts to investigate accounting factors, the discrepancy in pCR rate cannot be entirely explained by differences in patient, tumour, or treatment characteristics.
Optimal scheduling of flexible grid-side resources and auxiliary service cost allocation model considering renewable-energy penetration
Authors: Bai Bin , Xiao Yanli , Zhao Rui , Ju Xin , Liu Shangke
Published: May 2024

Renewable energy has penetrated power grid enterprises on a large scale. Due to the intermittency and volatility of renewable energy generation, it is necessary to build new flexible grid-side resources to ensure the safe and stable operation of the power grid, which will cause great pressure on cost allocation for power grid enterprises. This article considers four types of flexible grid-side resources and constructs a dual-level configuration optimization model for flexible grid-side resources under the penetration of renewable energy. Based on the configuration results, the cost scale of flexible grid-side resources is estimated and an improved ancillary service cost allocation model based on the Shapley value method is proposed to smooth the allocation of ancillary service costs in the cost of flexible grid-side resources between the two main bodies of renewable energy and load. The calculation results show that, when the penetration rate of renewable-energy power is 30% and 35%, respectively, the cost of flexible grid-side resources is 9.606 billion yuan and 21.518 billion yuan, respectively. The proportion of ancillary service costs allocated to load is relatively high—about five times that of the ancillary service costs allocated to renewable energy—and the higher the penetration rate of renewable energy, the higher the proportion of ancillary service costs allocated to renewable energy.
Associations Between Antiretroviral Regimen and Changes in Blood Pressure: Results From the D2EFT Study
Authors: Nyein Phyo Pyae , Petoumenos Kathy , Borok Margaret , Eriobu Nnakelu , Kumarasamy Nagalingeswaran , Avihingsanon Anchalee , Azwa Iskandar , Dao Sounkalo , Cisse Mohamed , Dharan Nila J , Hanson Josh , Matthews Gail V
Published: May 2024

In this randomized controlled study, individuals taking dolutegravir+darunavir/ritonavir had greater increases in systolic and diastolic blood pressure than those taking 2 nucleoside reverse-transcriptase inhibitors+darunavir/ritonavir at week-48. The difference remained significant after controlling for confounding factors, including weight gain.