bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical-pump–terahertz-probe spectroscopy in high magnetic fields with kHz single-shot detection
Authors: Dastrup Blake S. , Miedaner Peter R. , Zhang Zhuquan , Nelson Keith A.
Published: March 2024

We demonstrate optical pump–THz probe (OPTP) spectroscopy with a variable external magnetic field (0–9 T), in which the time-dependent THz signal is measured by echelon-based single-shot detection at a repetition rate of 1 kHz. The method reduces data acquisition times by more than an order of magnitude compared to conventional electro-optic sampling using a scanning delay stage. The approach illustrates the wide applicability of the single-shot measurement approach to non-equilibrium systems that are studied through OPTP spectroscopy, especially in cases where parameters such as magnetic field strength (B) or other experimental parameters are varied. We demonstrate the capabilities of our measurement by performing cyclotron resonance experiments in bulk silicon, where we observe B-field-dependent carrier relaxation and distinct relaxation rates for different carrier types. We use a pair of economical linear array detectors to measure 500 time points on each shot, offering an equivalent performance to camera-based detection with possibilities for higher repetition rates.
Chiral photon emission from a chiral–achiral perovskite heterostructure
Authors: Hu Yang , Chen Ruiwen , Pendse Saloni , Taniguchi Takashi , Watanabe Kenji , Jiang Jie , Zhang Lifu , Jia Ru , Palermo Edmund F. , Wertz Esther , Shi Jian
Published: March 2024

Chiral semiconductors have been recently suggested as the basic building blocks for the design of chiral optoelectronic and electronic devices for chiral emission and spintronics. Herein, we report that through the formation of a chiral/achiral heterostructure, one can develop a chiral system that integrates the merits of both chiral and achiral components for developing a demanded chiral emitter. In the R-(+)-(or S-(−)-)1-(1-naphthyl)-ethylammonium lead bromide/CsPbBr3 heterostructure, we show that the photoluminescence of CsPbBr3 carries a degree of circular polarization of around 1% at room temperature. It is explained that such chiral emission is enabled through the chiral self-trapped exitonic absorption of R-(+)- (or S-(−)-)1-(1-naphthyl)-ethylammonium lead bromide. This work may provide an alternative way to generate bright circularly polarized light from achiral materials, which has potential applications in spintronics, biosensing, and signal encryption.
3D cylindrical BGK model of electron phase-space holes with finite velocity and polarization drift
Authors: Gauthier Gaëtan , Chust Thomas , Le Contel Olivier , Savoini Philippe
Published: March 2024

Nonlinear kinetic structures, called electron phase-space holes (EHs), are regularly observed in space and experimental magnetized plasmas. The existence of EHs is conditioned and varies according to the ambient magnetic field and the parameters of the electron beam(s) that may generate them. The objective of this paper is to extend the 3D Bernstein–Greene–Kruskal model with cylindrical geometry developed by L.-J. Chen et al. [“Bernstein–Greene–Kruskal solitary waves in three-dimensional magnetized plasma,” Phys. Rev. E 69, 055401 (2004)] and L.-J. Chen et al., [“On the width-amplitude inequality of electron phase space holes,” J. Geophys. Res. 110, A09211 (2005)] to include simultaneously finite effects due to (i) the strength of the ambient magnetic field B0, by modifying the Poisson equation with a term derived from the electron polarization current, and (ii) the drift velocity ue of the background plasma electrons with respect to the EH, by considering velocity-shifted Maxwellian distributions for the boundary conditions. This allows us to more realistically determine the distributions of trapped and passing particles forming the EHs, as well as the width-amplitude relationships for their existence.
Intelligent computing for electromagnetohydrodynamic bioconvection flow of micropolar nanofluid with thermal radiation and stratification: Levenberg–Marquardt backpropagation algorithm
Authors: Khan Zeeshan , Alfwzan Wafa F. , Ali Aatif , Innab Nisreen , Zuhra Samina , Islam Saeed , Asamoah Joshua Kiddy K.
Published: March 2024

The Levenberg–Marquardt (LM) backpropagation optimization algorithm, an artificial neural network algorithm, is used in this study to perform integrated numerical computing to evaluate the electromagnetohydrodynamic bioconvection flow of micropolar nanofluid with thermal radiation and stratification. The model is then reduced to a collection of boundary value problems, which are solved with the help of a numerical technique and the proposed scheme, i.e., the LM algorithm, which is an iterative approach to determine the minimum of a nonlinear function defined as the sum of squares. As a blend of the steepest descent and the Gauss–Newton method, it has become a typical approach for nonlinear least-squares problems. Furthermore, the stability and consistency of the algorithm are ensured. For validation purposes, the results are also compared with those of previous research and the MATLAB bvp4c solver. Neural networking is also utilized for velocity, temperature, and concentration profile mapping from input to output. These findings demonstrate the accuracy of forecasts and optimizations produced by artificial neural networks. The performance of the bvp4c solver, which is used to reduce the mean square error, is used to generalize a dataset. The artificial neural network-based LM backpropagation optimization algorithm operates using data based on the ratio of testing (13%), validation (17%), and training (70%). This stochastic computing work presents an activation log-sigmoid function based LM backpropagation optimization algorithm, in which tens of neurons and hidden and output layers are used for solving the learning language model. The overlapping of the results and the small computed absolute errors, which range from 10−3 to 10−10 and from 106 to 108 for each model class, indicate the accuracy of the artificial neural network-based LM backpropagation optimization algorithm. Furthermore, each model case’s regression performance is evaluated as if it were an ideal model. In addition, function fitness and histogram are used to validate the dependability of the algorithm. Numerical approaches and artificial neural networks are an excellent combination for fluid dynamics, and this could lead to new advancements in many domains. The findings of this research could contribute to the optimization of fluid systems, resulting in increased efficiency and production across various technical domains.
Particle-in-cell/Monte Carlo collision simulation on gap breakdown characteristics of under the conditions of hot-electrode and high-temperature gas medium in low-voltage circuit breaker chamber
Authors: Wang Lijun , Hu Runze , Chen Zhuo , Wang Zhiwei
Published: March 2024

The gas composition inside the low-voltage circuit breaker (LVCB) chamber and the residual plasma in the post-arc stage affect the breakdown process, which in turn affects the breaking capacity of LVCBs. In this paper, the back-arc breakdown and post-arc re-breakdown phenomena occurring inside the LVCB chamber are categorized as the breakdown in the case of high-temperature gas gap of hot electrodes, for which a particle-in-cell/Monte Carlo collision simulation model has been established, which takes into account the effects of high-temperature gas components, cathode electron thermal emission, electron collision ionization, and other effects, and simulation studies have been conducted. The simulation results show that the gap breakdown is mainly caused by the high-temperature hot free background gas and the cathode thermal electron emission. A plasma sheath layer is formed at the cathode during the breakdown process, and the electric field strength in the sheath layer is higher than that in other regions. With the development of the streamer to the cathode, the thickness of the sheath layer becomes narrower and the electric field strength increases, and finally, a discharge plasma channel is formed in the gap.
Wave packet dynamics and control in excited states of molecular nitrogen
Authors: Fushitani Mizuho , Fujise Hikaru , Hishikawa Akiyoshi , You Daehyun , Saito Shu , Luo Yu , Ueda Kiyoshi , Ibrahim Heide , Légaré Francois , Pratt Stephen T. , Eng-Johnsson Per , Mauritsson Johan , Olofsson Anna , Peschel Jasper , Simpson Emma R. , Carpeggiani Paolo Antonio , Ertel Dominik , Maroju Praveen Kumar , Moioli Matteo , Sansone Giuseppe , Shah Ronak , Csizmadia Tamás , Dumergue Mathieu , Nandiga Gopalakrishna Harshitha , Kühn Sergei , Callegari Carlo , Danailov Miltcho , Demidovich Alexander , Raimondi Lorenzo , Zangrando Marco , De Ninno Giovanni , Di Fraia Michele , Giannessi Luca , Plekan Oksana , Rebernik Ribic Primoz , Prince Kevin C.
Published: March 2024

Wave packet interferometry with vacuum ultraviolet light has been used to probe a complex region of the electronic spectrum of molecular nitrogen, N2. Wave packets of Rydberg and valence states were excited by using double pulses of vacuum ultraviolet (VUV), free-electron-laser (FEL) light. These wave packets were composed of contributions from multiple electronic states with a moderate principal quantum number (n ∼ 4–9) and a range of vibrational and rotational quantum numbers. The phase relationship of the two FEL pulses varied in time, but as demonstrated previously, a shot-by-shot analysis allows the spectra to be sorted according to the phase between the two pulses. The wave packets were probed by angle-resolved photoionization using an infrared pulse with a variable delay after the pair of excitation pulses. The photoelectron branching fractions and angular distributions display oscillations that depend on both the time delays and the relative phases of the VUV pulses. The combination of frequency, time delay, and phase selection provides significant control over the ionization process and ultimately improves the ability to analyze and assign complex molecular spectra.
Machine-learning-assisted modeling of alloy ordering phenomena at the electronic scale through electronegativity
Authors: Zhao Dingqi , Jin Xi , Qiao Junwei , Zhang Yong , Liaw Peter K.
Published: March 2024

Many studies attribute the excellent properties of high-entropy alloys to the ordering-phenomena. It can be known from density functional theory that the macroscopic properties of the system can be described by the electron density. Electronegativity is related to electron density, and models describing ordering can be established based on electronegativity scales through machine learning. In this study, a large dataset was established and predicted the ordered state corresponding to the alloy composition. The accuracy of the model on the test set was 94%. Furthermore, this study used different methods to explain the machine learning model and learned more model information.
Quantum cascade lasers as broadband sources via strong RF modulation
Authors: Cargioli A. , Piciocchi D. , Bertrand M. , Maulini R. , Blaser S. , Gresch T. , Muller A. , Scalari G. , Faist J.
Published: March 2024

In this work, we demonstrate that in a regime of strong modulation, by generating pulses of the length of the order of a few cavity lifetimes (hundreds of ps), a broadband quantum cascade laser can be driven to lase on a bandwidth (250 cm−1) limited by the gain. In addition, the amplitude noise of the radiation was shown to be limited by the detector. A laser linewidth study has been performed under different operating conditions, finding values spanning from 20 to 800 MHz, indicating a trade-off between emission bandwidth, amplitude stability, and coherence. The pulsed intensity of the output arises from the gain switching dynamics of the laser, while the self-seeded nature of the emission is responsible for the low amplitude noise and the relatively narrow linewidth of the individual spectral lines of the multimode emission.
Surface depression recognition of spring plate based on feature construction and improved AdaBoost algorithm
Authors: Xu Kai , Zhang HuiFang , Wang ZhenXi , Yuan Yongliang
Published: March 2024

Machine learning has introduced novel solutions for the surface quality inspection of spring plates. Hence, an improved method was proposed based on logistic regression and AdaBoost (LR-RBAdaBoost) for recognizing surface depressions in spring plates. In order to obtain the measured attributes for spring plates, feature construction methods were adopted. Then, logistic regression was used to analyze and rank the attributes of the spring plate and the filter method was used for the feature selection process. To improve the predicted performance of AdaBoost, RBAdaBoost was proposed in this paper, which is used in the issue of recognition of surface defects in spring steel plates. The effectiveness and sophistication of LR-RBAdaBoost are validated on a real spring steel plate sampling dataset. The results show that the accuracy of LR-RBAdaBoost is 0.968 and f1-score is 0.967, which can be better than the results of only using AdaBoost, random forest, and CatBoost. Furthermore, the results prove that the research has a certain reference value for the recognition of spring plate as well.
Microstructural changes in GaN and AlN under 950 MeV Au swift heavy ion irradiation
Authors: Mahfuz Mahjabin , Reza Farshid , Liu Xingyu , Chu Rongming , Lang Maik , Snure Michael , Wang Xing , Jin Miaomiao
Published: March 2024

The radiation hardness of GaN-based devices is a critical metric for applications in extreme environments. This study investigates the structural changes in GaN and AlN induced by swift heavy ion (SHI) irradiation, characteristic of space radiation environments. A multilayered GaN/AlN structure is exposed to 950 MeV Au ions at fluences of 1×1012 and 8×1012 ions/cm2. Subsequent post-irradiation characterization, including transmission electron microscopy and energy-dispersive x-ray spectroscopy, reveal no apparent amorphization across the entire sample. Notably, significant nanometer-sized cavities are observed in both GaN and AlN. The cavities in GaN exhibit an increase in number density and diameter with increasing SHI irradiation, with the average diameter progressing from 1.80 to 2.10 nm. In contrast, cavities in AlN appear considerably smaller. Molecular dynamics simulations, coupled with the inelastic thermal spike model, reproduce the presence of cavities in GaN and no cavities in the AlN structure. This difference is attributed to the faster heat dissipation and stronger bonding in AlN. Considering the overlapping of ion impacts at high fluences, simulations confirm the enlargement of cavity size in GaN. These findings contribute to a mechanistic understanding of the contrast in ion–matter interactions and induced microstructures between AlN and GaN under extreme ionizing radiation conditions. This disparity could potentially impact electronic performance through the formation of defect traps and interfacial strain fields.
Magnonic notch filter based on spin wave caustic beams
Authors: Swyt Mitchell S. , Compton Lia , Reyes-Almanza Arturo , Romero César L. Ordóñez , Pirruccio Giuseppe , Liu H. J. Jason , Buchanan Kristen S.
Published: March 2024

Here, we study a magnonic crystal made of low-damping yttrium iron garnet that utilizes pseudo-caustic spin wave beams generated from subwavelength square well features arranged in a two-dimensional array. The lattice symmetry and the angle between the caustic beam propagation direction and the applied magnetic field were tailored to optimize the interaction of spin waves with the engineered defects. A prominent, narrow 3 MHz feature with large rejection efficiency is observed in the spin wave transmission spectrum that could be useful as a narrowband notch filter, and time- and space-resolved Brillouin light scattering (BLS) measurements suggest that both caustic interference and edge effects may contribute to this notch feature. Furthermore, the BLS measurements show that caustics are generated efficiently at the laser ablated wells, and by tuning the frequency by 30 MHz, the caustic beam angles and, hence, the details of how the spin wave caustics hit the ablated wells change sufficiently to add and remove caustic beams, which can be used to create additional device functionality. The generation and conversion of caustic beams show promise for applications that require directional energy transport and for magnonic devices.
Behavior of small water droplets in a highly viscous flow in a converging and diverging channel
Authors: Shayunusov D. , Eskin D. , Zeng H. , Nikrityuk P. A.
Published: March 2024

Understanding the evolution of water droplets moving in a highly viscous bulk flow (e.g., bitumen) has attracted increasing attention in the context of numerous separation technologies due to various issues relating to the environment (re-use of water) and engineering failures (corrosion of pipelines). With this in mind, the main objectives of this work are to explore the dynamics of water droplets with a diameter of seven micrometers, moving in highly viscous bitumen flowing through a smoothly converging and diverging 11-micron channel using three-dimensional (3D) and two-dimensional (2D) droplet-resolved simulations and to adjust an existing population balance model (PBM) to predict geometry-driven coalescence for different flow rates. The Eulerian–Eulerian (EE) method coupled with a new PBM is used to predict the behavior of water droplets with a diameter of 7 μm. Numerical simulations were carried out for various capillary numbers (0.1<Ca<3) and compared with the volume of fluid method combined with the level-set function (CLSVOF). Adaptive mesh refinement (up to six levels) was used in 3D and 2D CLSVOF simulations, producing interface cells measuring up to 30 nm. Good agreement was observed between EE-PBM and CLSVOF models. For comparison, we show the results of 2D CLSVOF simulations. This new PBM model can be used to predict water–oil separation in new cascade-formed geometries to enhance the coalescence of water droplets in highly viscous bulk flows.
The droplet race: Optimization of a wettability gradient surface
Authors: Koyeerath Graham Danny , Favennec Yann , Auvity Bruno , Josset Christophe
Published: March 2024

Droplet behavior influenced by wettability distribution is a pertinent field of research with applications in lab-on-a-chip and heat transfer devices among others. Some have proposed patterned surfaces with controlled variation of wettability to orient the direction of the droplet motion or to increase its velocity. These patterns are arrived upon with experience and knowledge of this phenomenon. In this research paper, the authors used a mathematical approach to the physical problem by using a gradient based optimizer for maximizing droplet velocity. Given some initial conditions, the optimizer marches toward the optimum wettability distribution profile. The droplet motion is modeled in two dimensions (i.e., on the xy-plane), on a plate having a wettability distribution in one dimension (i.e., along the x axis). The single component pseudopotential model allows for the quantification of the wettability distribution as a distribution of a pseudodensity of the solid nodes of the flat plate. Starting with several monotonous analytical profiles, a quadratic convex profile allows us to reach the maximum mean velocity for the threshold droplet displacement. Different sets of initial profiles, length of the plate (L), and diameter of the droplet (D) are tested. For smaller L/D ratio, the optimal wettability distributions exhibit non-trivial features: profiles can be non-monotonous, and wettability gradient could be locally null. With the increase in the L/D ratio, these specificities tend to be less prominent and optimal profiles converge to the quadratic convex one. The main innovation and significance of the paper is that mathematical optimization algorithms have been used conjointly with a multiphase lattice Boltzmann model solver to address for the first time the droplet race defined as: “what is the best wettability profile in order for a droplet to reach a desired location as quickly as possible?”
Dissipative stabilization of high-dimensional GHZ states for neutral atoms
Authors: Zhao Yue , Yang Yu-Qing , Li Weibin , Shao Xiao-Qiang
Published: March 2024

High-dimensional quantum entanglement characterizes the entanglement of quantum systems within a larger Hilbert space, introducing more intricate and complex correlations among the entangled particles' states. The high-dimensional Greenberger–Horne–Zeilinger (GHZ) state, symbolic of this type of entanglement, is of significant importance in various quantum information processing applications. This study proposes integrating a neutral atom platform with quantum reservoir engineering to generate a high-dimensional GHZ state deterministically. Leveraging the advantages of neutral atoms in a modified unconventional Rydberg pumping mechanism, combined with controlled dissipation, we achieve a three-dimensional GHZ state with a fidelity surpassing 99% through multiple pump and dissipation cycles. This innovative approach paves the way for experimentally feasible, deterministic preparation of high-dimensional GHZ states in Rydberg atom systems, thereby advancing the capabilities of quantum information processing.
A physics-guided machine learning framework for real-time dynamic wake prediction of wind turbines
Authors: Li Baoliang , Ge Mingwei , Li Xintao , Liu Yongqian
Published: March 2024

Efficient and accurate prediction of the wind turbine dynamic wake is crucial for active wake control and load assessment in wind farms. This paper proposes a real-time dynamic wake prediction model for wind turbines based on a physics-guided neural network. The model can predict the instantaneous dynamic wake field under various operating conditions using only the inflow wind speed as input. The model utilizes Taylor's frozen-flow hypothesis and a steady-state wake model to convert instantaneous inflow wind speed and turbine parameters into neural network input features. A deep convolutional neural network then maps these features to desired wake field snapshots, enabling dynamic wake predictions for wind turbines. To train the model, we generated approximately 255 000 instantaneous flow field snapshots of single-turbine wakes using the large eddy simulation, covering different thrust coefficients and yaw angles. The model was trained using the supervised learning method and verified on the test set. The results indicate that the model can effectively predict the dynamic wake characteristics, including the dynamic wake meandering and the wake deflection of the yawed turbines. The model can also assess both the instantaneous wake velocity and the instantaneous wake center of a wind turbine. At a thrust coefficient of 0.75, the root mean square error for the predicted instantaneous wake velocity is around 6.53%, while the Pearson correlation coefficient for the predicted instantaneous wake center can reach 0.624. Furthermore, once the model is trained, its prediction accuracy does not decrease with the increase in the time span.
Optimizing unconventional gas extraction: The role of fracture roughness
Authors: Wang Yapeng , Zhang Yongli , Yang Xinle , Dong Jinling , Ma Yulin
Published: March 2024

In unconventional reservoir engineering, such as coalbed methane and shale gas extraction, fracture behavior is pivotal in gas accumulation, migration, and extraction, acting as a primary channel for gas flow. Current research inadequately addresses the quantitative impact of fracture roughness on gas extraction. In this study, we introduce a novel interdisciplinary model that quantitatively characterizes shale fracture roughness and correlates it with shale permeability. This model comprehensively considers factors affecting shale extraction, including fracture roughness, in situ stress, reservoir deformation, and adsorption-desorption dynamics. It provides a thorough analysis of how fracture roughness influences gas seepage, extraction efficiency, and reservoir stability under various physical conditions. Our validated findings reveal that fracture roughness significantly affects shale permeability, stress responses, and displacement. As the fracture roughness coefficient χ increases from 0.2 to 1.0, the maximum reduction in gas pressure within the hydraulically fractured region is 4.7%, while the maximum increase in reservoir stress is 2.8%. In shale reservoirs near extraction well, particularly in hydraulically fractured zones, the maximum decrease in shale gas pressure is 11.1%, and the maximum increase in stress is 3.2%, which offer a groundbreaking approach for optimizing extraction rates and ensuring project safety in the industry.
Formation and propagation characteristics of a weak shock wave in maglev tube
Authors: Wang Kai-Wen , Xiong Xiao-Hui , Wen Chih-Yung , Chen Guang , Liang Xi-Feng , Huang Hua-Kun , Wang Jia-Bin
Published: March 2024

The propagation of the weak shock wave (WSW) to the tunnel exits and their radiation as micro-pressure waves (MPWs) may cause sonic booms or structural resonance of buildings, posing potential hazards to humans, animals, and buildings in the exit's environment. The characteristics of the WSW and sonic booms of a maglev train/tube coupling model were studied based on the two-dimensional axisymmetric unsteady Reynolds average Navier–Stokes turbulence model. In the later stage of a MPW, the formation mechanism, geometry, and kinematic characteristics of compressible vortex rings (CVRs) were systematically analyzed. The inertial effect causes the initial wavefront to gradually transition from a Gaussian-shape waveform to a triangular waveform during its propagation, eventually coalescing into a WSW. The overpressure, density jump, and shock Mach number at the WSW location all increase with the increasing train speed, while the WSW thickness decreases accordingly. The formation distance of the WSW is inversely proportional to the amplitude of the initial wavefront gradient, and the WSW directly causes the occurrence of the exit sonic boom. The MPW amplitude has significant directionality with a largest value in the axial direction. Within the speed range of 450–700 km/h, the sound pressure level of the MPW exceeds the hearing threshold and even reaches the feeling threshold. The evolution of CVRs includes primary CVR, secondary CVR, and Kelvin–Helmholtz vortices. Primary CVR has the greatest impact on the axial MPW among them. The occurrence of CVRs will cause a second small noise level other than the sonic boom.
Acid molecule-assisted high-quality SnO2 transport layer for perovskite solar cells
Authors: Tan Junwei , Ren Guanhua , Han Wenbin , Deng Yanyu , Li Zhuowei , Liu Chunyu , Guo Wenbin
Published: March 2024

The SnO2 electron transport layer (ETL) serves a critical role in perovskite solar cells. However, the oxygen vacancy defects and excess hydroxyl (–OH) groups in SnO2 always lead to degradation of device performance. Herein, we introduce iminodiacetic acid (IDA) to modify the SnO2 ETL, yielding three key advantages: (1) IDA can neutralize excess –OH groups and passivate the defects in SnO2, diminishing the decomposition of perovskite layer; (2) the IDA-modified SnO2 exhibits superior electron conductivity and film quality, while providing improved energy level alignment with the perovskite layer; and (3) the IDA-modified SnO2 owns superior surface wetting properties that facilitates a more effective perovskite crystallization. Ultimately, the devices based on IDA-modified SnO2 obtain a champion efficiency of 24.02% and enhanced stability.
High-fidelity correspondence imaging in complex media with varying thresholds and 1-bit compressive sensing
Authors: Xu Zhihan , Song Qian , Chen Wen
Published: March 2024

Here, we report high-fidelity correspondence imaging (CI) in complex media. By introducing varying thresholds to binarize single-pixel light intensities recorded in complex media, dynamic scaling factors can be eliminated. Then, the binarized light intensities and illumination patterns can be fed into a modified 1-bit compressive sensing algorithm to realize high-fidelity object reconstruction. The proposed method can implement object reconstruction with high fidelity in complex media without extra temporal carriers. It is experimentally verified that the method can effectively eliminate dynamic scaling factors and realize high-fidelity object reconstruction in complex media where conventional CI methods could fail. Experimental results demonstrate that the proposed method broadens a potential application of CI in complex media, e.g., turbid water, biological tissues, and dynamic smoke.
Interactions between elementary waves and weak discontinuity in two-layer blood flow through artery
Authors: Mondal Rakib , Minhajul  , Raja Sekhar T.
Published: March 2024

Blood flow through arterial circulation can be characterized by fluid transport in flexible tubes and modeled mathematically using the conservation of mass and momentum. A one-dimensional model for two-layer blood flow with different blood velocities and the same constant density in each layer derived from the Euler equations of gas dynamics by taking the vertical average across each layer. This work presents interactions of elementary waves with a weak discontinuity for the quasilinear 3 × 3 system of conservation laws governing the two-layer blood flow in arteries. Exploiting elementary waves as a single-parameter curve, we study the Riemann solution uniquely and consequently establish the condition on initial data for the existence of a solution to the Riemann problem. Furthermore, we discuss the evolution of weak discontinuity waves and subsequently derive their amplitudes; in what follows, we investigate the interactions of weak discontinuity with contact discontinuity and shocks. Finally, a series of numerical tests have been performed to understand the impact of shock strength and the initial data on the amplitudes of reflected and transmitted waves and the jumps in shock acceleration.
Optimization of multi-staged Tesla valve using response surface methodology
Authors: Li Pengju , Liu Yinghan , Wen Qingguo , Zhang Zhengkai , Ma Yawen , Zhu Jianwei
Published: March 2024

The multi-stage Tesla valve (MSTV), which consists of multiple identical TVs in series, enhances the effectiveness of the TV. To further improve the performance of the MSTV, an improved MSTV has been proposed by designing each arch channel in the typical MSTV as two separate arch channels: the inner arch channel and the outer arch channel. Response surface methodology is used to optimize the improved MSTV, with the maximum mass flow rate in forward flow and the minimum mass flow rate in reverse flow as two optimization objectives. The non-dominated sorting genetic algorithm is employed to obtain the Pareto solution set, resulting in the optimized design for the improved MSTV (named short-baffle improved MSTV). Theoretical simulations and experimental research are conducted on a typical MSTV, an improved MSTV, and a short-baffle improved MSTV, and their flow resistance ratios (FRRs) are obtained. The FRR of the short-baffle improved MSTV has improved by an average of 8.70% compared to that of typical MSTV. At low inlet pressures, the increase in FRR is approximately 1.4% higher than that at high inlet pressures. The research results indicate that the FRR of the shot-baffle improved MSTV is greater than that of a typical MSTV, and to some extent, the performance of an MSTV is enhanced under low inlet pressure.
Comparatively poorer body condition of south-east Indian Ocean pygmy blue whales on their southern migration
Authors: Russell Grace , Jolliffe Capri , Elsdon Brodie , Christiansen Fredrik , Colefax Andrew , Cagnazzi Daniele
Published: March 2024

The south-east Indian Ocean population of pygmy blue whales (Balaenoptera musculus brevicauda) forages in habitats between temperate foraging grounds off southern Australia and breeding grounds in Indonesian waters. With the opportunity to forage during migration, limited seasonal variation in body condition would be expected. However, increasing numbers of individuals in poor body condition with prominent spinal columns and other features of emaciation have been sighted during their southern migration. This study aimed to measure the morphology and body condition (relative body volume to body length) of pygmy blue whales during their northbound and southbound migration. Unmanned aerial vehicles were used to obtain images of 42 pygmy blue whales (one calf, five juveniles and 36 adults, including one lactating female) in 2021 and 2022. The body lengths ranged from 15.32 to 24.32 m, and the mean relative head length, length to blowhole, width of eyes, fluke width and length of peduncle were 21.8, 18.1, 12.8, 22.9 and 21.3% respectively. There was a significant decrease in body condition of 15.3% between north and southern migrating adult whales. Given the importance of body condition for reproductive success, understanding if this loss is due to natural seasonal variation, or habitat or prey disturbance from environmental environmental or anthropogenic sources, has implications for the future management of the species.
Collective neural network behavior in a dynamically driven disordered system of superconducting loops
Authors: Goteti Uday S. , Cybart Shane A. , Dynes Robert C.
Published: March 2024

Collective properties of complex systems composed of many interacting components such as neurons in our brain can be modeled by artificial networks based on disordered systems. We show that a disordered neural network of superconducting loops with Josephson junctions can exhibit computational properties like categorization and associative memory in the time evolution of its state in response to information from external excitations. Superconducting loops can trap multiples of fluxons in many discrete memory configurations defined by the local free energy minima in the configuration space of all possible states. A memory state can be updated by exciting the Josephson junctions to fire or allow the movement of fluxons through the network as the current through them surpasses their critical current thresholds. Simulations performed with a lumped element circuit model of a 4-loop network show that information written through excitations is translated into stable states of trapped flux and their time evolution. Experimental implementation on a high-Tc superconductor YBCO-based 4-loop network shows dynamically stable flux flow in each pathway characterized by the correlations between junction firing statistics. Neural network behavior is observed as energy barriers separating state categories in simulations in response to multiple excitations, and experimentally as junction responses characterizing different flux flow patterns in the network. The state categories that produce these patterns have different temporal stabilities relative to each other and the excitations. This provides strong evidence for time-dependent (short-to-long-term) memories, that are dependent on the geometrical and junction parameters of the loops, as described with a network model.
A diterpene synthase from the sandfly
Lutzomyia longipalpis
produces the pheromone sobralene
Authors: Ducker Charles , Baines Cameron , Guy Jennifer , Euzébio Goulart Santana Antônio , Pickett John A. , Oldham Neil J.
Published: March 2024

The phlebotomine sandfly,
Lutzomyia longipalpis
, a major vector of the
Leishmania
parasite, uses terpene pheromones to attract conspecifics for mating. Examination of the
L. longipalpis
genome revealed a putative terpene synthase (TPS), which—upon heterologous expression in, and purification from,
Escherichia coli
—yielded a functional enzyme. The TPS, termed
Ll
TPS, converted geranyl diphosphate (GPP) into a mixture of monoterpenes with low efficiency, of which β-ocimene was the major product. (
E,E
)-farnesyl diphosphate (FPP) principally produced small amounts of (
E
)-β-farnesene, while (
Z,E
)- and (
Z,Z
)-FPP yielded a mixture of bisabolene isomers. None of these mono- and sesquiterpenes are known volatiles of
L. longipalpis
. Notably, however, when provided with (
E,E,E
)-geranylgeranyl diphosphate (GGPP),
Ll
TPS gave sobralene as its major product. This diterpene pheromone is released by certain chemotypes of
L. longipalpis
, in particular those found in the Ceará state of Brazil. Minor diterpene components were also seen as products of the enzyme that matched those seen in a sandfly pheromone extract.
975 nm multimode semiconductor lasers with high-order Bragg diffraction gratings
Authors: Liu Zhenwu , Zhong Li , Liu Suping , Ma Xiaoyu
Published: March 2024

The 975 nm multimode diode lasers with high-order surface Bragg diffraction gratings have been simulated and calculated using the 2D finite difference time domain (FDTD) algorithm and the scattering matrix method (SMM). The periods and etch depth of the grating parameters have been optimized. A board area laser diode (BA-LD) with high-order diffraction gratings has been designed and fabricated. At output powers up to 10.5 W, the measured spectral width of full width at half maximum (FWHM) is less than 0.5 nm. The results demonstrate that the designed high-order surface gratings can effectively narrow the spectral width of multimode semiconductor lasers at high output power.
Emission and capture characteristics of deep hole trap in n-GaN by optical deep level transient spectroscopy
Authors: Sui Jin , Chen Jiaxiang , Qu Haolan , Zhang Yu , Lu Xing , Zou Xinbo
Published: March 2024

Emission and capture characteristics of a deep hole trap (H1) in n-GaN Schottky barrier diodes (SBDs) have been investigated by optical deep level transient spectroscopy (ODLTS). Activation energy (E
emi) and capture cross-section (σ
p) of H1 are determined to be 0.75 eV and 4.67 × 10−15 cm2, respectively. Distribution of apparent trap concentration in space charge region is demonstrated. Temperature-enhanced emission process is revealed by decrease of emission time constant. Electric-field-boosted trap emission kinetics are analyzed by the Poole−Frenkel emission (PFE) model. In addition, H1 shows point defect capture properties and temperature-enhanced capture kinetics. Taking both hole capture and emission processes into account during laser beam incidence, H1 features a trap concentration of 2.67 × 1015 cm−3. The method and obtained results may facilitate understanding of minority carrier trap properties in wide bandgap semiconductor material and can be applied for device reliability assessment.
Control of temperature dependent viscosity for manufacturing of Bi-doped active fiber
Authors: Duan Rui , Chen Jingfei , Ke Hao , Wei Tianxia , Zhang Ke , Li Xueliang , Feng Xu , Zheng Qiuju , He Zhixue , Qiu Jianrong , Zhou Shifeng
Published: March 2024

Bi-activated photonic materials are promising for various applications in high-capacity telecommunication, tunable laser, and advanced bioimaging and sensing. Although various Bi-doped material candidates have been explored, manufacturing of Bi heavily doped fiber with excellent optical activity remains a long-standing challenge. Herein, a novel viscosity evolutional behavior mediated strategy for manufacturing of Bi-doped active fiber with high dopant solubility is proposed. The intrinsic relation among the evolution of Bi, reaction temperature and viscosity of the glass system is established. Importantly, the effective avenue to prevent the undesired deactivation of Bi during fiber drawing by tuning the temperature dependent viscosity evolution is built. By applying the strategy, for the first time we demonstrate the success in fabrication of heavily doped Bi active fiber. Furthermore, the principal fiber amplifier device is constructed and broadband optical signal amplification is realized. Our findings indicate the effectiveness of the proposed temperature dependent viscosity mediated strategy for developing novel photonic active fiber, and they also demonstrate the great potential for application in the next-generation high-capacity telecommunication system.
Complexity of patients with mental healthcare needs cared for by mental health clinical pharmacist practitioners in Veterans Affairs
Authors: Jasuja Guneet K , Reisman Joel I , Miller Donald R , Ansara Elayne D , Chiulli Dana L , Moore Tera , Ourth Heather L , Tran Michael H , Smith Eric G , Morreale Anthony P , McCullough Megan M
Published: March 2024

Purpose

The complexity of patients with mental healthcare needs cared for by clinical pharmacists is not well delineated. We evaluated the complexity of patients with schizophrenia, bipolar disorder, and major depressive disorder (MDD) in Veterans Affairs (VA) cared for by mental health clinical pharmacist practitioners (MH CPPs).

Methods

Patients at 42 VA sites with schizophrenia, bipolar disorder, or MDD in 2016 through 2019 were classified by MH CPP visits into those with 2 or more visits (“ongoing MH CPP care”), those with 1 visit (“consultative MH CPP care”), and those with no visits (“no MH CPP care”). Patient complexity for each condition was defined by medication regimen and service utilization.

Results

For schizophrenia, more patients in ongoing MH CPP care were complex than those with no MH CPP care, based on all measures examined: the number of primary medications (15.3% vs 8.1%), inpatient (13.7% vs 9.1%) and outpatient (42.6% vs 29.7%) utilization, and receipt of long-acting injectable antipsychotics (36.7% vs 25.8%) and clozapine (20.5% vs 9.5%). For bipolar disorder, more patients receiving ongoing or consultative MH CPP care were complex than those with no MH CPP care based on the number of primary medications (27.9% vs 30.5% vs 17.7%) and overlapping mood stabilizers (10.1% vs 11.6% vs 6.2%). For MDD, more patients receiving ongoing or consultative MH CPP care were complex based on the number of primary medications (36.8% vs 35.5% vs 29.2%) and augmentation of antidepressants (56.1% vs 54.4% vs 47.0%) than patients without MH CPP care. All comparisons were significant (P < 0.01).

Conclusion

MH CPPs provide care for complex patients with schizophrenia, bipolar disorder, and MDD in VA.
Risks of glaucoma among individuals with psoriasis: a population-based cohort study
Authors: Li Shu-Hao , Cheng Chun-Yu
Published: March 2024

Background

Psoriasis is a chronic systemic disorder with ocular involvement.

Objectives

To evaluate the risk of glaucoma among patients with psoriasis.

Methods

Participants in this cohort study were selected based on Chang Gung Research Database from 1 January 2003 to 31 December 2012. Follow-up ended on 31 December 2017. The participants in the control group were matched with the psoriasis group by sex, age and index date with a 4 : 1 ratio. The hazard ratios of glaucoma were estimated using Cox regression analysis. We also evaluated the relationship between the risk of glaucoma and systemic therapies as well as phototherapy and topical corticosteroid in patients with psoriasis.

Results

In total, 6682 patients with psoriasis and 26 728 matched controls were enrolled. The study population was composed mainly of males accounting for 64.2% (21 445/33 410) of the study population. The psoriasis group had higher incidence rates than the control group for glaucoma (adjusted hazard ratio 1.405, 95% confidence interval, 1.051–1.879). Patients with psoriasis receiving psoralen–ultraviolet A (PUVA) therapy for > 200 sessions had an increased risk of glaucoma.

Conclusions

Patients with psoriasis had an increased risk of glaucoma. Long-term PUVA therapy raised the risk of glaucoma in people with psoriasis.
Extensive calcinosis cutis complicating radiotherapy
Authors: Ryan Sarah , Kravvas Georgios , Wilson James M , Bunker Christopher B
Published: March 2024

Dystrophic calcinosis cutis is a rare late sequela of radiotherapy, and can cause a significant impact on quality of life. Management of the condition can be challenging. However, we achieved effective symptomatic relief with injection of triamcinolone.
Tofacitinib ameliorates skin inflammation in a patient with severe autosomal recessive congenital ichthyosis
Authors: Lin Yu-Chen , Hong Yi-Kai , Aala Wilson Jr F , Hitomi Kiyotaka , Akiyama Masashi , McGrath John A , Hsu Chao-Kai
Published: March 2024

Autosomal recessive congenital ichthyosis (ARCI) is a genetically heterogeneous disorder with aberrant skin scaling and increased transepidermal water loss (TEWL). Current treatments for ARCI are limited and suboptimal. We present the case of a 27-year-old man with ARCI resulting from a homozygous missense variant in TGM1. RNA-sequencing of lesional skin revealed aberrant Janus kinase–signal transducer and activator of transcription signalling, providing a rationale for innovative treatment with a Janus kinase inhibitor. We prescribed oral tofacitinib (11 mg daily) for 26 weeks. Rapid improvements in erythema and fissuring occurred within the first month. Sustained reductions in 5-D itch scale and Dermatology Life Quality Index scores were also observed. TEWL decreased for the first 10 weeks but increased thereafter. Tofacitinib downregulated inflammatory genes and pathways, while enhancing skin barrier markers. Moreover, transglutaminase 1 distribution was normalized although enzymatic activity remained deficient. This study suggests that oral tofacitinib may be a useful therapy to consider for patients with ARCI.
Secukinumab therapy for paediatric patients with various phenotypes of congenital ichthyosis
Authors: Albela Henrietta , Ting Ingrid Pao Lin , Lee Tyan Shin , Ooi Deirdre , Leong Kin Fon
Published: March 2024

This case series demonstrates that secukinumab therapy for paediatric patients with congenital ichthyosis is safe and has variable efficacy, similar to results from clinical trials in adults. A good response is seen in patients with the erythrodermic phenotypes, namely congenital ichthyosiform erythroderma and Netherton syndrome, with a minor response seen in lamellar ichthyosis phenotypes. Clinical data are overall lacking for the paediatric population, and this study adds some insights to the existing research.
Increased Risk of New-Onset Parkinson’s Disease Following a Diagnosis of Retinal Vascular Occlusion: A 14-Year Cohort Study
Authors: Kim Seung Hoon , Park Minah , Jeong Sung Hoon
Published: March 2024

Background

Although the role of the vascular component in the pathophysiology of Parkinson’s disease is widely accepted and retinal vascular abnormalities are commonly observed in Parkinson’s disease patients, evidence connecting retinal vascular disorders with the risk of developing Parkinson’s disease is limited. We aimed to investigate the association between retinal vascular occlusion (RVO) and the risk of developing Parkinson’s disease in people over 60 years using a nationwide cohort.

Methods

From the 14-year South Korean National Health Insurance Service-Senior cohort, 11 210 incident RVO patients and 11 210 propensity scores, risk-matched controls were included. The incidence of Parkinson’s disease was estimated with a Poisson regression. A Cox proportional hazards regression model was used to investigate the associations between RVO and the risk of Parkinson’s disease.

Results

The incidence of Parkinson’s disease was 664.4 cases per 100 000 person-years (95% confidence interval [CI], 599.7–736.0) in the RVO cohort. Individuals with RVO had an increased incidence of Parkinson’s disease (hazard ratio [HR], 1.28; 95% CI: 1.10–1.49). Increased PD risk was predominantly observed in retinal artery occlusion patients (HR, 1.53; 95% CI: 1.11–2.12), male patients (HR, 1.67; 95% CI: 1.29–2.17), and 5 years after diagnosis (HR, 1.46; 95% CI: 1.10–1.93).

Conclusions

Our findings suggest that a common pathophysiological pathway, such as vasculature changes, may exist between RVO and Parkinson’s disease. RVO may be one of the risk factors associated with future development of Parkinson’s disease. The nature of this association warrants further investigation.