bluuebunny/crossref_metadata_2025 huggingface dataset:
Cracks at shallow nanoindentation depths in titanium diboride hard thin coatings used in AFM nanoindentation
Authors: Bhattacharyya Arnab S.
Published: May 2024

Hard coatings like Titanium diboride (TiB2) on silicon substrates which are used for interconnects. micro-electro-mechanical devices and metallurgical protective coatings were analyzed based on shallow depths of nanoindentation penetration. The change in the nature of the contact from Hertzian to Pyramidal both in loading as well as unloading modes were examined. Features like ductile fracture, linear unloading, and the creation of electrical conduction paths were analyzed. These high-precision features are influenced by the thickness and crystalline nature of the films and are significant for device fabrication.
Distribution of Money on Connected Graphs with Multiple Banks
Authors: Lanchier Nicolas , Reed Stephanie
Published: May 2024

This paper studies an interacting particle system of interest in econophysics inspired from a model introduced in the physics literature. The original model consists of the customers of a single bank characterized by their capital, and the dynamics consists of monetary transactions in which a random individual x gives one coin to another random individual y, the transaction being canceled when x is in debt and there are no more coins in the bank. Using a combination of numerical simulations and heuristic arguments, physicists conjectured that the distribution of money (the random number of coins owned by a given individual) at equilibrium converges to an asymmetric Laplace distribution in the large population limit when the money temperature is large. We prove and extend this conjecture to a more general model including multiple banks and interactions among customers across banks. More importantly, we assume that customers are located on a general undirected connected graph (as opposed to the complete graph in the original model) where neighbors are interpreted as business partners, and transactions occur along the edges, thus modeling the flow of money across a social network. We first derive an exact expression for the distribution of money for all population sizes and money temperatures, then prove its convergence to an asymmetric Laplace distribution in the large population limit.
Untangling the Derogenes varicus species complex in Scandinavian waters and the Arctic: description of Derogenes abba n. sp. (Trematoda, Derogenidae) from Hippoglossoides platessoides and new host records for D. varicus (Müller, 1784) sensu stricto
Authors: Bouguerche Chahinez , Huston Daniel C. , Karlsbakk Egil , Ahmed Mohammed , Holovachov Oleksandr
Published: May 2024

Several studies have shown that the euryxenic trematode Derogenes varicus (Müller, 1784) represents a species complex. Four lineages have been designated (DV1–4) with the DV1 clade corresponding to D. varicus sensu stricto. Herein, we investigate newly collected specimens of D. varicus sensu lato from Scandinavian and Arctic waters using integrative taxonomy. The trematodes were collected from Melanogrammus aeglefinus, Eutrigla gurnardus, Trachinus draco, and Merluccius merluccius off the Atlantic coast of Sweden and from Hippoglossoides platessoides from Arctic Svalbard. 28S sequences of derogenids from Sweden were identical to D. varicus sensu stricto, confirming its euryxeny. The 28S sequences of Derogenes sp. from H. platessoides were identical to Derogenes DV2 and differed from D. varicus sensu stricto by 3% and from Derogenes DV3 by 2%. The 28S sequence divergences of Derogenes sp. from H. platessoides with D. ruber and D. lacustris were 3 and 10%, respectively. ITS2 and cox1 divergences between Derogenes sp. from H. platessoides and other Derogenes species/lineages were at levels of interspecific differences. The species from H. platessoides is described here as D. abba n. sp. We also examined the type material of Progonus muelleri (Levinsen, 1881), the type and only species of the genus Progonus, with redescription and designations of paralectotypes. Based on specimens from Theodor Odhner’s collections at the Swedish Museum of Natural History, SMNH, Stockholm, we provide novel morphological and anatomical data for D. varicus sensu lato species complex. Lastly, we investigated Arthur Looss’s “lost collection” of Trematodes at the SMNH and characterised a putative species Derogenes sp. “limula”.
Radiologic Outcomes after Operative Management of Traumatic Spine Fractures: Stand-Alone Posterior Stabilization versus Combined Anteroposterior Approach
Authors: Mulhem Ali , Omran Ziad , Hammersen Stefanie , Kantelhardt Sven Rainer
Published: May 2024

Background Previous research emphasizes correcting deformities resulting from spine fractures by restoring sagittal alignment and vertebral height. This study aims to compare radiologic outcomes, including sagittal index (SI) and loss of vertebral body height (LVBH), between stand-alone posterior stabilization (group I) and the posteroanterior/combined approach (group II) in the operative management of traumatic thoracic or lumbar spine fractures.

Methods In this retrospective single-center study, all patients with traumatic spine fractures (T1–L5) undergoing surgical stabilization between January 1, 2015, and May 31, 2021, were included. Two spine surgeons independently assessed imaging, recording the SI and LVBH values at baseline, after each surgical intervention, and during follow-up (at least 3 months posttreatment). The mean SI and LVBH values between the assessing surgeons were utilized. Linear mixed-effects regression models, adjusted to baseline values, compared the SI and the LVBH values between the two groups.

Results In all, 71 patients (42 men), with the median age of 38 years (interquartile range [IQR]: 28–54) and median follow-up of 4 months (IQR: 3–17), were included. Thirty-two patients were in group I and 39 patients were in group II. Forty fractures included the thoracolumbar junction (T12 or L1), 15 affected the thoracic spine, and 14 the lumbar spine. The regression model revealed superior sagittal alignment in group II, with an adjusted mean difference for SI of –4.24 (95% confidence interval [CI]: –7.13 to –1.36; p = 0.004), and enhanced restoration of vertebral body height with an adjusted mean difference for LVBH of 0.11 in the combined approach (95% CI: 0.02–0.20; p = 0.02). Nine postoperative complications occurred in the entire cohort (4 in group I and 5 in group II).

Conclusions Combined posteroanterior stabilization for spine fractures improves deformities by enhancing sagittal alignment and increasing vertebral body height, with acceptable morbidity compared with the stand-alone posterior approach.
Deucravacitinib Induces Proteasomal Degradation of YAP1 in Human Glioblastoma Cells
Authors: Wang Shaonan , Sun Min , Su Yajuan , Xu Zhou , Li Ang , He Weiwei
Published: May 2024

Deucravacitinib is a selective allosteric inhibitor of tyrosine kinase 2 (TYK2) recently approved by the FDA for the treatment of plaque psoriasis. We discovered that this compound induces proteasomal degradation of YAP1, the downstream effector of the Hippo signaling pathway, in human glioblastoma (GBM) cells (U-87 MG). This degradation is independent of the canonical Hippo pathway, which offers clues to alternative mechanisms for YAP1 regulation.
Role of Ga68 Prostate-Specific Membrane Antigen Positron Emission Tomography-Computed Tomography in Prostate Cancer Imaging
Authors: Amalachandran Jaykanth , Sivathapandi Thangalakshmi , Gunasekaran Gopinathraj
Published: May 2024

The introduction of prostate-specific membrane antigen (PSMA) in clinical practice has revolutionized the evaluation of biochemical recurrence (BCR) of prostate cancer after curative-intent treatment. The high expression of this glycoprotein in prostate cancer cells makes PSMA imaging superior to the current conventional staging methods, namely bone scanning and computed tomography. The high capability of PSMA imaging for identifying very small previously undetected lesions has been widely demonstrated in the literature, leading to a rethinking of patient management by treating physicians. The usual and predictable patterns of spread in prostate cancer are still more prevalent, such as spread to pelvic lymph nodes and bone metastasis, but different patterns of disease spread are becoming more commonly recognized with higher reliability because PSMA imaging allows the detection of more usual and unusual lesions than conventional imaging. The expanding use of PSMA positron emission tomography (PET) has also revealed PSMA ligand uptake in diverse nonprostatic diseases, which raised questions about the specificity of this imaging modality. It is important for the reading physician to recognize and understand the usual disease spread, the most prevalent unusual sites of relapse, and the nonprostatic conditions which are PSMA avid not only to heighten the relevancy of reports but also to improve imaging consultancy in multispecialty oncologic practice. This article aims to brief the role of PSMA PET in the initial staging of multitude of clinical scenarios, BCR, castration-resistant prostate cancer, usual and unusual patterns of recurrence and metastatic spread diagnosed with PSMA PET, normal variants, pitfalls, and nonprostatic disorders showing PSMA expression.
Valley splitting by extended zone effective mass approximation incorporating strain in silicon
Authors: Noborisaka Jinichiro , Hayashi Toshiaki , Fujiwara Akira , Nishiguchi Katsuhiko
Published: May 2024

We propose a main mechanism of large valley splitting experimentally observed at the interface of buried oxide (BOX)/silicon-on-insulator (SOI) structures. Silicon metal-oxide-semiconductor field effect transistors fabricated on a SIMOX (001) substrate, which is a kind of the SOI substrate, that is annealed at high temperatures for a long time are known to exhibit large valley splitting, but the origin of this splitting has long been unknown. Extended zone effective-mass approximation predicts that strain significantly affects valley splitting. In this study, we analyzed valley splitting based on this theory and found that the shear strain along [110] of approximately 5% near the BOX interface is a promising source for large valley splitting.
Control of seizure-like dynamics in neuronal populations with excitability adaptation related to ketogenic diet
Authors: Eydam Sebastian , Franović Igor , Kang Louis
Published: May 2024

We consider a heterogeneous, globally coupled population of excitatory quadratic integrate-and-fire neurons with excitability adaptation due to a metabolic feedback associated with ketogenic diet, a form of therapy for epilepsy. Bifurcation analysis of a three-dimensional mean-field system derived in the framework of next-generation neural mass models allows us to explain the scenarios and suggest control strategies for the transitions between the neurophysiologically desired asynchronous states and the synchronous, seizure-like states featuring collective oscillations. We reveal two qualitatively different scenarios for the onset of synchrony. For weaker couplings, a bistability region between the lower- and the higher-activity asynchronous states unfolds from the cusp point, and the collective oscillations emerge via a supercritical Hopf bifurcation. For stronger couplings, one finds seven co-dimension two bifurcation points, including pairs of Bogdanov–Takens and generalized Hopf points, such that both lower- and higher-activity asynchronous states undergo transitions to collective oscillations, with hysteresis and jump-like behavior observed in vicinity of subcritical Hopf bifurcations. We demonstrate three control mechanisms for switching between asynchronous and synchronous states, involving parametric perturbation of the adenosine triphosphate (ATP) production rate, external stimulation currents, or pulse-like ATP shocks, and indicate a potential therapeutic advantage of hysteretic scenarios.
On formation, annihilation, and evolution of potential wells, and nonlinear phenomena of multi-magnet energy sink system
Authors: Gao Mingyuan , Wang Yuan , Wang Ping
Published: May 2024

This paper investigates the formation, annihilation, and evolution mechanisms of potential energy wells in nonlinear energy sink systems. The nonlinear energy sink system is composed of multiple inner and outer magnets. Two multi-magnet energy sink (MES) architectures are designed: a single-magnet vibrator and a double-magnet vibrator. Multi-stable (bi-, tri-, quad-, penta-, hexa-, and hepta-stable) mechanisms are elaborated by the Poincaré section and bifurcation diagram concerning the magnet length, the link length, and the MES configuration. The results show that the change in the internal structural parameters of the MES system will generate different types of bifurcations (i.e., saddle-node, subcritical, and super pitchfork bifurcations) and phase trajectories and have rich nonlinear response behaviors in the low frequency and wide frequency range, which can be used for damping and vibration reduction of engineering structures, vibration control, and energy source of the microgrid.
Mitigation of microwave crosstalk with parameterized single-qubit gate in superconducting quantum circuits
Authors: Yang Z. H. , Wang Ruixia , Wang Z. T. , Zhao Peng , Huang Kaixuan , Xu Kai , Tian Ye , Yu H. F. , Zhao S. P.
Published: May 2024

In superconducting qubit systems, microwave crosstalk among the qubit control lines is a prominent source of errors for gate operations, particularly when implemented simultaneously in a multiqubit system. In this work, we present an experimental study of crosstalk mitigation for the case of single-qubit gate operation, which involves the universal U3 gate decomposition into two Xπ/2 gates and three virtual Z gates. We demonstrate that by optimizing the virtual Z gate parameters, the crosstalk can be effectively mitigated, with the single-qubit gate fidelity recovered to the level comparable to that in the absence of crosstalk.
Compositionally complex carbide ceramics: A perspective on irradiation damage
Authors: Trinh Lanh , Wang Fei , Bawane Kaustubh , Hattar Khalid , Hua Zilong , Malakkal Linu , He Lingfeng , Wadle Luke , Lu Yongfeng , Cui Bai
Published: May 2024

Extensive experimental and computational studies have demonstrated outstanding physical and chemical properties of the novel materials of compositionally complex carbides (CCCs), enabling their promising applications in advanced fission and fusion energy systems. This perspective provides a comprehensive overview of radiation damage behavior reported in the literature to understand the fundamental mechanisms related to the impact of multi-principal metal components on phase stability, irradiation-induced defect clusters, irradiation hardening, and thermal conductivity of compositionally complex carbides. Several future research directions are recommended to critically evaluate the feasibility of designing and developing new ceramic materials for extreme environments using the transformative “multi-principal component” concept. Compared to the existing materials for nuclear applications including stainless steels, nickel alloys, ZrC, SiC, and potentially high-entropy alloys, as well as certain other compositionally complex ceramic families. CCCs appear to be more resistant to amorphization, growth of irradiation defect clusters, and void swelling.
Ca(CF3SO3)2 all-in-one modification on CsPbI3 all-inorganic perovskite solar cells for improved performance and stability
Authors: Chang Binbin , Yuan Yuqi , Hou Linsong , Wang Wanjiang , Lin Ping , Wang Peng , Wu Xiaoping , Yu Xuegong , Xu Lingbo , Cui Can
Published: May 2024

Due to the low tolerance factor, the black-phase CsPbI3 could easily transform into the photovoltaic-inactive yellow phase under the pressure of moisture, restricting the performance and stability of corresponding solar cells. Here, Ca(CF3SO3)2 is introduced into CsPbI3 to solve this problem. The Ca2+ cations could interact with I− ions to inhibit ion migration and prevent the collapse of the perovskite structure, while the CF3SO3− anions anchoring on the crystal surface could provide hydrophobicity. Ca(CF3SO3)2 introduction, thus, increases the intrinsic and extrinsic stability of black-phase CsPbI3 simultaneously. The interaction between Ca(CF3SO3)2 and perovskite precursors retards the crystallization process and facilitates the growth of high-quality films with reduced non-radiative recombination. Moreover, the CF3SO3− anions on the surface induce p-type doping and modify the energy level alignment with the hole transport layer. Benefiting from the Ca(CF3SO3)2 introduction, the CsPbI3 all-inorganic perovskite solar cells exhibit improved power conversion efficiency (PCE) from 14.76% to 16.50%. In addition, the unencapsulated device with Ca(CF3SO3)2 retains 81% of its original PCE after storage in air for 500 h, outperforming that of the control device (65%).
Intermittency, an inevitable feature for faster convergence of large eddy simulations
Authors: Bock Marcel , Yassin Khaled , Kassem Hassan , Theron Johannes , Lukassen Laura J. , Peinke Joachim
Published: May 2024

Gaussian and intermittent synthetically generated turbulences are investigated as initial conditions for high-resolution numerical simulations. Turbulent fields, namely the Mann and the intermittent Time-mapped Mann model, are injected into large eddy simulations, and subsequently their convergences are investigated. In addition to the usual one-point and two-point characterizations, the higher moments of the velocity increments are addressed to grasp the intermittency. Here, we show that independent of the initial conditions, the evolving turbulence converges to a common state, which is well represented by the classical intermittent turbulence of Kolmogorov. The findings reveal that if the intermittency parameters of the inflow field are adjusted to those of the common state, the convergence behavior is much faster.
Optically detected magnetic resonance study of thermal effects due to absorbing environment around nitrogen-vacancy-nanodiamond powders
Authors: Jani Mona , Orzechowska Zuzanna , Mrózek Mariusz , Mitura-Nowak Marzena , Gawlik Wojciech , Wojciechowski Adam M.
Published: May 2024

We implanted Fe+ ions in nanodiamond (ND) powder containing negatively charged nitrogen-vacancy (NV−) centers and studied their Raman spectra and optically detected magnetic resonance (ODMR) in various applied magnetic fields with green light (532 nm) excitation. In Raman spectra, we observed a blue shift of the NV− peak associated with the conversion of the electronic sp3 configuration to the disordered sp2 one typical for the carbon/graphite structure. In the ODMR spectra, we observed a red shift of the resonance position caused by local heating by an absorptive environment that recovers after annealing. To reveal the red shift mechanism in ODMR, we created a controlled absorptive environment around ND by adding iron-based Fe2O3 and graphitic sp2 powders to the ND suspension. This admixture caused a substantial increase in the observed shift proportional to the applied laser power, corresponding to an increase in the local temperature by 150–180 K. This surprisingly large shift is absent in non-irradiated NV-ND powders, is associated only with the modification of the local temperature by the absorptive environment of NV-NDs, and can be studied using ODMR signals of NV−.
Primary breakup of a jet coupled with vortex-induced string cavitation in a fuel injector nozzle
Authors: Guan Wei , Huang Yunlong , He Zhixia , Guo Genmiao , Wang Chuqiao , Thévenin Dominique
Published: May 2024

Fuel jet primary breakup strongly depends on the in-nozzle cavitation phenomena found in the high-pressure fuel injector nozzle. Nevertheless, limited attention has been paid to the mechanism of fuel jet primary breakup induced by in-nozzle vortex-induced string-type cavitation. This study involves simulations of in-nozzle string cavitating flow and simultaneously near-nozzle jet primary breakup process using large eddy simulation and volume of fluid, aiming at revealing the effects of string cavitation on jet primary breakup. The numerical results are in good agreement with experimental data in terms of string cavitation intensity, interfacial topology of jet, and spray spreading angle. The numerical investigations indicate that the external surface of the jet experiences Kelvin–Helmholtz instabilities, which results in the development of circumferential and axial surface waves at the fuel film surface. Subsequently, the fuel film surface undergoes progressive wrinkling, resulting in its breakup into multiple ligaments and large droplets. On the internal side of the jet, back-suction of air caused by negative pressure and its interaction with cavitation vapor at the core of the jet lead to the collapse of vapor bubbles. The resulting pressure waves and micro-jets facilitate the detachment of liquid sheets from the internal surface of the jet. Analysis of the enstrophy transport equation indicates that the driving mechanism behind string cavitation jet breakup further downstream is the baroclinic torque term, which is responsible for the generation of a cascade of smaller vortical structures. This effect dominates over vortex stretching and dilatation terms.
Modeling microgel swelling: Influence of chain finite extensibility
Authors: Brito Mariano E. , Holm Christian
Published: May 2024

Microgels exhibit the ability to undergo reversible swelling in response to shifts in environmental factors that include variations in temperature, concentration, and pH. While several models have been put forward to elucidate specific aspects of microgel swelling and its impact on bulk behavior, a consistent theoretical description that chains throughout the microscopic degrees of freedom with suspension properties and deepens into the full implications of swelling remains a challenge yet to be met. In this work, we extend the mean-field swelling model of microgels from Denton and Tang [J. Chem. Phys. 145, 164901 (2016)] to include the finite extensibility of the polymer chains. The elastic contribution to swelling in the original work is formulated for Gaussian chains. By using the Langevin chain model, we modify this elastic contribution in order to account for finite extensibility effects, which become prominent for microgels containing highly charged polyelectrolytes and short polymer chains. We assess the performance of both elastic models, namely for Gaussian and Langevin chains, comparing against coarse-grained bead–spring simulations of ionic microgels with explicit electrostatic interactions. We examine the applicability scope of the models under a variation of parameters, such as ionization degree, microgel concentration, and salt concentration. The models are also tested against experimental results. This work broadens the applicability of the microgel swelling model toward a more realistic description, which brings advantages when describing the suspensions of nanogels and weak-polyelectrolyte micro-/nanogels.
A large-scale filament-free planar plume generated by an argon plasma jet in a gas-confined barrier discharge geometry
Authors: Chen Mo , Dong Xiupin , Wu Kaiyue , Ran Junxia , Jia Pengying , Wu Jiacun , Li Xuechen
Published: May 2024

Large-scale plumes in a plasma jet are desirable for fast processing of materials with large surface, which are normally composed of discharge filaments. A filamentary plume may cause nonuniform treatment or even damage to vulnerable samples. In this Letter, an argon plasma jet in a gas-confined barrier discharge geometry is proposed to generate a large-scale filament-free plume. Results indicate that the filament-free plume can only be sustained in a relatively low voltage amplitude (Vp), which transits to the filamentary plume with increasing Vp. There is only one negative discharge per voltage cycle for the filament-free plume, while both positive and negative discharges for the filamentary plume. Fast photography reveals that the negative discharge is diffuse, originating from the propagation of a negative streamer. On the contrary, the positive discharges are filamentary. Optical emission spectroscopy indicates that the filament-free plume has lower electron density, electron excitation temperature, and molecular vibrational temperature compared to the filamentary plume, while gas temperature keeps at a low value with varying Vp.
Temperature-dependent characterization of full tensor properties of [111]c poled Mn-doped 28PIN-43PMN-29PT single crystals
Authors: Xiao Ailing , Tang Liguo , Xu Guisheng , Wu Kechen , Luo Wenyu
Published: May 2024

The temperature-dependent characterization of full tensor properties of single-domain relaxor-based single crystals (SCs) is important for understanding the influence of temperature on the properties of their multidomain SCs. However, no relevant results have been published because characterization is difficult to achieve using the traditional electric resonance method. In this Letter, the temperature-dependent elastic and piezoelectric properties of single-domain [111]c poled Mn-doped 28Pb(In1/2Nb1/2)O3-43Pb(Mg1/3Nb2/3)O3-29PbTiO3 SCs were investigated in the range of 20–80 °C by resonant ultrasound spectroscopy (RUS) using a rectangular parallelepiped sample. The temperature-dependent dielectric constants were calculated from the measured capacitances of the sample. The results are self-consistent because they were obtained from the same sample. The elastic constants obtained using the ultrasonic pulse-echo method agree closely with those obtained using RUS. Moreover, the experimental results of electric impedance spectrum agree closely with those simulated using the material constants characterized herein, indicating that the characterization is reliable.
Advanced conductors could double power flows on the grid
Authors: Kramer David
Published: May 2024

Widespread reconductoring of the US transmission system could ease bottlenecks that are preventing renewable energy sources from hooking up to power grids.
Characteristic BOLD signals are detectable in white matter of the spinal cord at rest and after a stimulus
Authors: Sengupta Anirban , Mishra Arabinda , Wang Feng , Chen Li Min , Gore John C.
Published: May 2024

We report the reliable detection of reproducible patterns of blood-oxygenation-level-dependent (BOLD) MRI signals within the white matter (WM) of the spinal cord during a task and in a resting state. Previous functional MRI studies have shown that BOLD signals are robustly detectable not only in gray matter (GM) in the brain but also in cerebral WM as well as the GM within the spinal cord, but similar signals in WM of the spinal cord have been overlooked. In this study, we detected BOLD signals in the WM of the spinal cord in squirrel monkeys and studied their relationships with the locations and functions of ascending and descending WM tracts. Tactile sensory stimulus –evoked BOLD signal changes were detected in the ascending tracts of the spinal cord using a general-linear model. Power spectral analysis confirmed that the amplitude at the fundamental frequency of the response to a periodic stimulus was significantly higher in the ascending tracts than the descending ones. Independent component analysis of resting-state signals identified coherent fluctuations from eight WM hubs which correspond closely to the known anatomical locations of the major WM tracts. Resting-state analyses showed that the WM hubs exhibited correlated signal fluctuations across spinal cord segments in reproducible patterns that correspond well with the known neurobiological functions of WM tracts in the spinal cord. Overall, these findings provide evidence of a functional organization of intraspinal WM tracts and confirm that they produce hemodynamic responses similar to GM both at baseline and under stimulus conditions.
AMPK regulates phagophore-to-autophagosome maturation
Authors: Barnaba Carlo , Broadbent David G. , Kaminsky Emily G. , Perez Gloria I. , Schmidt Jens C.
Published: May 2024

Autophagy is an important metabolic pathway that can non-selectively recycle cellular material or lead to targeted degradation of protein aggregates or damaged organelles. Autophagosome formation starts with autophagy factors accumulating on lipid vesicles containing ATG9. These phagophores attach to donor membranes, expand via ATG2-mediated lipid transfer, capture cargo, and mature into autophagosomes, ultimately fusing with lysosomes for their degradation. Autophagy can be activated by nutrient stress, for example, by a reduction in the cellular levels of amino acids. In contrast, how autophagy is regulated by low cellular ATP levels via the AMP-activated protein kinase (AMPK), an important therapeutic target, is less clear. Using live-cell imaging and an automated image analysis pipeline, we systematically dissect how nutrient starvation regulates autophagosome biogenesis. We demonstrate that glucose starvation downregulates autophagosome maturation by AMPK-mediated inhibition of phagophore tethering to donor membrane. Our results clarify AMPKs regulatory role in autophagy and highlight its potential as a therapeutic target to reduce autophagy.
Research on online monitoring method for time-varying tension in transmission lines based on operational modal response
Authors: Liu Zhicheng , Zhao Long , Wen Guanru , Wang Jingyao , Wang Jiameng , Huang Xinbo
Published: May 2024

The cumulative overload of conductor tension under severe weather conditions is an important cause of accelerated fatigue fracture of transmission lines. Traditional tension measurement methods require the replacement of ball head hanging rings, which poses safety risks. In this paper, a method for monitoring conductor tension based on acceleration data under operating conditions is proposed. Firstly, a modal order extraction based method for identifying the modal frequencies of conductor operation is proposed, and then the time-varying tension of the conductor is estimated based on the instantaneous modal frequencies. Since this method directly installs sensors on the conductor, there is a certain error in the obtained intrinsic characteristic data of the conductor. Therefore, a modal correction method is used to remove the influence of the sensors. The accuracy of modal identification, modal correction, and tension identification methods is verified through finite element models. Based on the above methods, a monitoring system for conductor tension status is designed, and the feasibility of this system is verified through experiments. Finally, the vibration data obtained from the field engineering pilot test is successfully used for conductor tension analysis. The results show that the proposed method can effectively identify time-varying tension and provide a new approach for monitoring the status of transmission line conductors.
An object detection method for catenary component images based on improved Faster R-CNN
Authors: Wu Changdong , He Xu , Wu Yanliang
Published: May 2024

Catenary components are an important part of electrified railways. Especially for catenary support devices, there are various types of components with significant differences in scale. According to statistical data, there is a high risk of failure for the catenary support device components during the operation of the catenary system. Therefore, in order to ensure the safe operation of the railways, it is critical to accurately locate and recognize the components in the catenary images. In this paper, we propose an improved method based on faster region-based convolutional neural networks (Faster R-CNN) framework to realize the detection and extraction of the components on the catenary support devices. Firstly, the anchor box parameters are reset using the K-means clustering method, which greatly improves the localization precision of the predicted box. Secondly, scaled exponential linear units activation function is introduced to improve the algorithm performance. Moreover, ResNet-34, the backbone of Faster R-CNN, is optimized. We design a transition structure for multi-scale filter combination convolution to avoid missing feature information and eliminate some redundant convolution structures. This modification substantially enhances the capability of the model to recognize a wide variety of component types. Finally, we conduct some control experiments comparing with single shot multibox detector and you only look once (YOLO) series (YOLOv3, YOLOv5 and YOLOv7) models. They are faster but less accurate, especially for small objects. The results show that the proposed method has better detection performance, achieving a mean average precision of 96.50% and running at 17.79 frames per second. In addition, our model has the highest average recall of 69.27%, which is 2.66% higher than the original model.
Zinc oxide nanoparticles encapsulated in alginate beads: a promising and recyclable adsorbent for simultaneous uptake of toxic metals
Authors: Çevik Tuğba Nur , Kivilcimdan Moral Çiğdem
Published: May 2024

Heavy metal toxicity is a known problem and various methods are used for treatment. Adsorption has some advantages and it would be promising if environmentally friendly and cheap materials were utilized. Alginate and zinc oxide nanoparticles were selected and composite alginate beads were used for the removal of mixed metals from aqueous solutions. Batch and column experiments were conducted to determine some parameters’ effects and the adsorbent’s real application potential. According to the batch experiments, zinc oxide nanoparticles to alginate ratio of 0.5 g g−1, and pH levels nearby to the neutral range led to better metal removals. 0.5 ml min−1 of flow rate supplied better metal removal efficiencies in columns, with the highest treatment as 86% of Pb2+. Acid treatment can be successfully applied for the regeneration of the adsorbent, at least three times only with a 4% reduction in the adsorption efficiency. Heavy metal uptake was compatible with the pseudo 2nd order model indicating chemisorption as a dominant mechanism. Also, the intraparticle diffusion model illustrated adsorption might govern more than one step. The Langmuir model had the best fit and suggested monolayer covering for Pb2+, 76.3 mg g−1. Alginate-based nanocomposite beads were useful for mixed metal removal and could be used.
Continuous monitoring methods of cerebral compliance and compensatory reserve: a scoping review of human literature
Authors: Islam Abrar , Froese Logan , Bergmann Tobias , Gomez Alwyn , Sainbhi Amanjyot Singh , Vakitbilir Nuray , Stein Kevin Y , Marquez Izabella , Ibrahim Younis , Zeiler Frederick A
Published: May 2024

Objective. Continuous monitoring of cerebrospinal compliance (CC)/ cerebrospinal compensatory reserve (CCR) is crucial for timely interventions and preventing more substantial deterioration in the context of acute neural injury, as it enables the early detection of abnormalities in intracranial pressure (ICP). However, to date, the literature on continuous CC/CCR monitoring is scattered and occasionally challenging to consolidate. Approach. We subsequently conducted a systematic scoping review of the human literature to highlight the available continuous CC/CCR monitoring methods. Main results. This systematic review incorporated a total number of 76 studies, covering diverse patient types and focusing on three primary continuous CC or CCR monitoring metrics and methods—Moving Pearson’s correlation between ICP pulse amplitude waveform and ICP, referred to as RAP, the Spiegelberg Compliance Monitor, changes in cerebral blood flow velocity with respect to the alternation of ICP measured through transcranial doppler (TCD), changes in centroid metric, high frequency centroid (HFC) or higher harmonics centroid (HHC), and the P2/P1 ratio which are the distinct peaks of ICP pulse wave. The majority of the studies in this review encompassed RAP metric analysis (n = 43), followed by Spiegelberg Compliance Monitor (n = 11), TCD studies (n = 9), studies on the HFC/HHC (n = 5), and studies on the P2/P1 ratio studies (n = 6). These studies predominantly involved acute traumatic neural injury (i.e. Traumatic Brain Injury) patients and those with hydrocephalus. RAP is the most extensively studied of the five focused methods and exhibits diverse applications. However, most papers lack clarification on its clinical applicability, a circumstance that is similarly observed for the other methods. Significance. Future directions involve exploring RAP patterns and identifying characteristics and artifacts, investigating neuroimaging correlations with continuous CC/CCR and integrating machine learning, holding promise for simplifying CC/CCR determination. These approaches should aim to enhance the precision and accuracy of the metric, making it applicable in clinical practice.
Fast ion confinement in the presence of core magnetic islands in Wendelstein 7-X
Authors: Lazerson Samuel A , Geiger Joachim , Kulla David , LeViness Alexandra , Bozhenkov Sergey , Killer Carsten , Ogawa Kunihiro , Isobe Mitsutaka , McNeely Paul , Rust Norbert , Hartmann Dirk ,   the W7-X Team
Published: May 2024

The effect of magnetic islands in the core region of Wendelstein 7-X (W7-X) on fast ion confinement is explored through simulations with the BEAMS3D code. A magnetic configuration where the

n

/

m
=
5

/

5

island chain is shifted to

r

/

a
∼
0.7

allows the exploration of core island physics in W7-X. The control coil system on W7-X allows the tuning of the island size either increasing the island width or decreasing it. A coupling of the BEAMS3D code to the FIELDLINES code provides a versatile mechanism for incorporating magnetic islands and stochastic regions into the BEAMS3D code. Collisionless simulations suggest that the presence of core islands degrade the confinement of passing particles in the region of the island chain. Full neutral beam simulations of W7-X show a similar behavior with confinement decreasing as the island width is increased. Comparisons between a vacuum magnetic field and low beta HINT2 simulation are made showing similar fast ion behavior. Measurements of lost fast ions in W7-X confirm this trend with the control coil suppressed island configuration showing lower losses than that with no control coils applied. Simulations of fast ion wall loads are performed suggesting no drastic change in loss pattern and a slight reduction in losses with minimized islands.
Delocalization and higher-order topology in a nonlinear elastic lattice
Authors: Yi Jianlin , Chen Chang Qing
Published: May 2024

Topological elastic waves provide novel and robust ways for manipulating mechanical energy transfer and information transmission, with potential applications in vibration control, analog computation, and more. Recently discovered higher-order topological insulators (HOTIs) with multidimensional and hierarchical edge states can further expand the capabilities of topological elastic waves. However, the effects of nonlinearity on elastic HOTIs remain elusive. In this paper, we propose a nonlinear elastic higher-order topological Kagome lattice. After briefly reviewing its linear properties, we explore the effects of nonlinearity on the higher-order band topology and topological states. To do this, we have developed a method to calculate approximate nonlinear modes in order to identify the bulk polarization and probe the higher-order topological phase in the nonlinear lattice. We find that nonlinearity induces unusual delocalization of topological corner states, band crossing, and higher-order topological phase transition. The delocalization reveals that intracell hardening nonlinearity leads to direct delocalization of topological corner states while intracell softening nonlinearity first enhances and then reduces localization. The nonlinear higher-order topological phase is amplitude dependent, and we demonstrate a transition from a trivial to a non-trivial phase, enabling amplitude induced topological corner and edge states. Additionally, this phase transition corresponds to the closing and reopening of the bandgap, accompanied by an unusual band crossing. By examining the band topology before and after the band crossing, we find that the bulk polarization becomes quantized with respect to amplitude and can predict higher-order topological phases in nonlinear lattices. The obtained results are expected to be beneficial for the development of tunable and robust elastic wave devices.
Novel vacancy-ordered RbKGeCl6 and RbKGeBr6 double perovskites for optoelectronic and thermoelectric applications: an ab-initio DFT study
Authors: Pingak Redi Kristian , Harbi Amine , Moutaabbid M , Nitti Fidelis , Sianturi Hery L , Johannes Albert Z , Hauwali Nikodemus U J
Published: May 2024

The present study examines the key characteristics of new vacancy-ordered halide double perovskites, RbKGeCl6 and RbKGeBr6, encompassing the elastic, structural, mechanical, optoelectronic, and thermoelectric properties. The Density Functional Theory (DFT) was employed to perform the calculation of the properties, facilitating the evaluation of their potential applications in optoelectronic and thermoelectric devices. The DFT calculation was conducted using the Quantum Espresso package alongside the thermo_pw tool and the BoltzTraP codes. The results revealed that the two proposed compounds possess both chemical and mechanical stability with optimized lattice constants recorded at 10.14 Å and 10.72 Å for RbKGeCl6 and RbKGeBr6, respectively. The evaluation of the elastic properties of the materials suggested reasonably high mechanical moduli of the materials. Based on the calculated electronic properties, the materials are classified as direct gap semiconductors, with energy gap values of 2.11 eV for RbKGeCl6 and 0.80 eV for RbKGeBr6 using the GGA-PBE functional. Furthermore, the use of the SCAN approximation yields more reliable energy gap of 2.51 eV and 1.08 eV for the respective compounds. The materials exhibited a high absorption coefficient and a significantly low reflectivity within the visible-ultraviolet energy spectrum. These findings strongly suggest the promising properties of the materials under study for optoelectronic applications. Furthermore, the calculated thermoelectric properties of the materials, particularly the figure of merit, revealed the materials’ potential use as thermoelectric materials. The calculated figure of merit values of RbKGeCl6 and RbKGeBr6 were found to range from 0.73 to 0.75, respectively, between 300 K and 800 K. Despite being lower, these values are comparable to those of some well-established materials including SiGe alloys (0.95), Bi2Te3 (≈0.90), and PbTe (≈0.80).
Ultrafast active plasmonic switch based on the broadband high absorption of monolayer graphene with high modulation depth
Authors: Najafgholinezhad Samira , Pourmahyabadi Maryam
Published: May 2024

Optical switches based on plasmonic nanostructures are of great interest due to their high speed performance. To improve the broadband switching performance, a plasmonic design based on metal-insulator-metal (MIM) structure and monolayer graphene (as an active layer) is proposed. In this scheme, the light absorption of the monolayer graphene and the optical bandwidth are increased due to magnetic dipole resonance and magnetic coupling effect. The numerical simulation results of the proposed structure reveal that high absorption is achieved at the wavelength of 1.55 ‌μm which is 67% and 93% for the monolayer graphene and the whole structure, respectively. This structure has a high absorption modulation depth which can be reached nearly 100% around the interband transition position in a wide wavelength range from 1 μm to 2.5 ‌‌‌‌‌μm. Also, regarding its short response time of 10 fs, this structure can be used as an ultrafast switch. In addition, the equivalent circuit model of the structure is derived from the transmission line model (TLM) that its results are in a very good agreement with the numerical simulation results.
A two-dimensional chaotic model and its application in image encryption
Authors: Lei RongQing , Liu LingFeng
Published: May 2024

In this paper, we propose a rule that follows a time-varying delay construction method and construct a time-varying delay scheme based on it. This construction scheme is also combined with a polynomial to obtain a novel two-dimensional chaotic model. Both mathematical analysis and experimental results show that the model satisfies the chaos condition. Good experimental results have been achieved in complexity analysis, information entropy analysis, and Auto-correlation analysis, and have certain competitiveness. The obtained chaotic model is also applied to the image encryption algorithm. The experimental results show that the encryption algorithm has high security and can effectively resist noise attacks, shear attacks, differential attacks.
Closed-form asymptotic solution for the transport of chlorine concentration in composite pipes
Authors: Mubaraki Ali M , Nuruddeen Rahmatullah Ibrahim , Gómez-Aguilar J F
Published: May 2024

Recently, some researchers have revisited the analysis of chlorine transportation in cylindrical pipes by deploying a coupling between the Laplace transform method and the complex analysis’ residue approach for inverting complex integrals. This method yielded interesting results after the incorporation of root-finding numerical schemes. Thus, away from incorporating numerical tools, the present study makes consideration of the same formulation of chlorine transport in a single-layered pipe and further extends it to the case of a bi-layered pipe using the hybrid of the Laplace transform method and the asymptotic approximations method. The need for asymptotic approximations for the modified Bessel functions, which arise in the reduced ordinary differential equations, necessitates the quest for closed-form analytical solutions, which are largely considered benchmark solutions for numerical investigations. Moreover, the obtained closed-form asymptotic solutions have been examined graphically; where it was observed that both the radial diffusion coefficient η and the spatial radial variable are contributory in the transport of chorine concentration in the media.
Attention-guided graph structure learning network for EEG-enabled auditory attention detection
Authors: Zeng Xianzhang , Cai Siqi , Xie Longhan
Published: May 2024

Objective: Decoding auditory attention from brain signals is essential for the development of neuro-steered hearing aids. This study aims to overcome the challenges of extracting discriminative feature representations from electroencephalography (EEG) signals for auditory attention detection (AAD) tasks, particularly focusing on the intrinsic relationships between different EEG channels. Approach: We propose a novel attention-guided graph structure learning network, AGSLnet, which leverages potential relationships between EEG channels to improve AAD performance. Specifically, AGSLnet is designed to dynamically capture latent relationships between channels and construct a graph structure of EEG signals. Main result: We evaluated AGSLnet on two publicly available AAD datasets and demonstrated its superiority and robustness over state-of-the-art models. Visualization of the graph structure trained by AGSLnet supports previous neuroscience findings, enhancing our understanding of the underlying neural mechanisms. Significance: This study presents a novel approach for examining brain functional connections, improving AAD performance in low-latency settings, and supporting the development of neuro-steered hearing aids.