bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Modified Frailty Index on Readmissions Following Surgery for NSCLC
Authors: Tamburini Nicola , Dolcetti Francesco , Fabbri Nicolò , Azzolina Danila , Greco Salvatore , Maniscalco Pio , Dolci Giampiero
Published: March 2024

Background Analyzing the risk factors that predict readmissions can potentially lead to more individualized patient care. The 11-factor modified frailty index is a valuable tool for predicting postoperative outcomes following surgery. The objective of this study is to determine whether the frailty index can effectively predict readmissions within 90 days after lung resection surgery in cancer patients within a single health care institution.

Methods Patients who underwent elective pulmonary resection for nonsmall cell lung cancer (NSCLC) between January 2012 and December 2020 were selected from the hospital's database. Patients who were readmitted after surgery were compared to those who were not, based on their data. Propensity score matching was employed to enhance sample homogeneity, and further analyses were conducted on this newly balanced sample.

Results A total of 439 patients, with an age range of 68 to 77 and a mean age of 72, were identified. Among them, 55 patients (12.5%) experienced unplanned readmissions within 90 days, with an average hospital stay of 29.4 days. Respiratory failure, pneumonia, and cardiac issues accounted for approximately 67% of these readmissions. After propensity score matching, it was evident that frail patients had a significantly higher risk of readmission. Additionally, frail patients had a higher incidence of postoperative complications and exhibited poorer survival outcomes with statistical significance.

Conclusion The 11-item modified frailty index is a reliable predictor of readmissions following pulmonary resection in NSCLC patients. Furthermore, it is significantly associated with both survival and postoperative complications.
Bone Bruise versus Fracture on MRI and the Relevance to Return to Play
Authors: Belair Jeffrey A. , Zoga Adam C.
Published: March 2024

We review the spectrum of acute osseous injuries in athletes, ranging from osseous contusion (bone bruise) injuries to nondisplaced cortical fractures. The basic biomechanical concepts, underlying histopathologic changes, and characteristic magnetic resonance imaging (MRI) features of acute osseous injuries are presented. Bone bruise injuries of varying severity are highlighted to showcase the breadth of imaging findings on MRI and methods for characterizing such lesions. We emphasize the importance of accurately assessing patterns of injury on MRI to communicate more effectively with team medical staff and recognize the implications on return to play. This article offers the foundational tools for approaching bone bruise injuries in elite athletes to add value to the diagnosis and treatment of this unique patient population.
Neural embeddings of urban big data reveal spatial structures in cities
Authors: Fan Chao , Yang Yang , Mostafavi Ali
Published: March 2024

Over decades, many cities have been expanded and functionally diversified by population activities, socio-demographics and attributes of the built environment. Urban expansion and development have led to the emergence of spatial structures of cities. Uncovering cities’ spatial structures is critical to understanding various urban phenomena such as segregation, equity of access, and sustainability. In this study, we propose using a neural embedding model—graph neural network (GNN)—that leverages the heterogeneous features of urban areas and their interactions captured by human mobility networks to obtain vector representations of these areas. Using large-scale high-resolution mobility data sets from millions of aggregated and anonymized mobile phone users in 16 metropolitan counties in the United States, we demonstrate that our embeddings encode complex relationships among features related to urban components (such as distribution of facilities) and population attributes and activities. The clustered representations of urban areas show the shared characteristics among urban areas in the same cluster. We show that embeddings generated by a model trained on a different county can capture 50% to 60% of the spatial structure in another county, allowing us to make cross-county comparisons and inferences. The findings reveal complex relationships among urban components in cities. Since the identified multifaceted spatial structures capture the combined effects of various mechanisms, such as segregation, disparate facility distribution, and human mobility, the findings could help identify the limitations of the current city structure to inform planning decisions and policies. Also, the model and findings set the stage for a variety of research in urban planning, engineering and social science through an integrated understanding of how the complex interactions between urban components and population activities and attributes shape the spatial structures in cities.
Does corporate digital transformation restrain ESG decoupling? Evidence from China
Authors: Chen Xiangyu , Wan Peng , Ma Zhefeng , Yang Yu
Published: March 2024

This paper empirically examines the efficacy of corporate digital transformation on a firm’s environmental, social, and governance (ESG) decoupling. Adopting the text analysis method and using a sample of Chinese A-share listed firms from 2010 to 2019, this paper finds that digital transformation can significantly alleviate ESG decoupling, and this relationship persists after robustness tests. Mechanism analysis reveals that digital transformation reduces ESG decoupling by improving information processing ability and relieving information asymmetry. The relationship between corporate digital transformation and ESG decoupling is stronger among companies in eastern China and firms that do not follow GRI guidance. The economic consequence analysis suggests that corporate digital transformation promotes firms’ high-quality development by reducing ESG decoupling. This study helps reveal corporate digital transformation’s empowering role and governance role in ESG decoupling and contributes to the growing literature on ESG decoupling and corporate digital transformation.
True or false? Linguistic and demographic factors influence veracity judgment of COVID-19 rumors
Authors: Fu Cun , Zhang Jinru , Kang Xin
Published: March 2024

Rumors about COVID-19 have been prevalent around the world during the pandemic. Using a veracity judgment task, the present study investigates whether young adults (N = 112) demonstrated measurable differences in processing COVID-19 rumors during the pandemic. They were instructed to read a statement related to COVID-19 and then to evaluate whether it was true or false. We examine the influence of the content characteristics of the statement and the demographic variables on the reading times, the accuracy rates, and the response times of the veracity judgment. We found that the reading times of rumors were only influenced by the length of rumors. Participants spent more time reading a rumor when it was longer. The length of rumors also influenced the accuracy rates of the veracity judgment. Participants were less accurate when the rumor was longer. Furthermore, we found that participants were faster at correctly rejecting false rumors than at accepting true rumors. Importantly, we found a significant effect of family socioeconomic status (SES) on the accuracy rates for which participants from families with higher SES had higher accuracy rates of veracity judgment. Our results demonstrated that both content characteristics (i.e., length) and demographic variables (i.e., family SES) influenced the veracity judgment of COVID-19 rumors.
Transparent, flexible capacitor for ionotronic wearable technology
Authors: Shapiro Maura
Published: March 2024

Lithium chloride hydrogel enabled 99% transparency and efficiency energy storage in electrochemical capacitors.
Exploring alternative paradigms for piezoelectric energy harvesters
Authors: Thompson Avery
Published: March 2024

Designing piezoelectric generators as data collectors themselves, rather than as power for data collectors, could reduce their energy demand and increase their viability.
Optimum asymmetry for nanofabricated refractometric sensors at quasi-bound states in the continuum
Authors: Watanabe Keisuke , Iwanaga Masanobu
Published: March 2024

A symmetry-protected bound state in the continuum (BIC) is one of the bases for high-resolution photonic refractometric sensors that rely on spectral shifts. However, a trade-off exists between the quality (Q) factors and the resonance amplitudes when the asymmetries of the unit cell are changed, making it difficult to intuitively determine the optimal nanostructural geometry. In this study, we present a theoretical and experimental approach for identifying the asymmetry parameters of dielectric metasurfaces that yield the lowest limit of detection (LOD). Silicon-based metasurfaces with asymmetric pair-rod arrays are fabricated experimentally, and the minimum LOD is obtained under a critical coupling condition with equal radiative and nonradiative Q factors. The results agree well with the theoretical model derived from the temporal coupled-mode theory. We reveal that the LOD and the optimum asymmetry are significantly influenced by nonradiative losses in the nanostructure, emphasizing the importance of loss reduction in dielectric metasurfaces at quasi-BICs for high-performance refractometric sensors.
Dispersion and damping of magnetohydrodynamic modes in radiative plasmas
Authors: Sadiq Safeer , Mahmood Shahzad
Published: March 2024

The presented work introduces a theoretical model for radiative magnetohydrodynamics (RMHD) in the equilibrium diffusion limit, focusing on the dynamics of radiation energy. For small amplitude waves, the basic set of dynamic equations is perturbed to derive the dispersion relation for three fundamental modes: fast, intermediate, and slow magnetosonic waves in RMHD plasmas. The study reveals that both fast and slow magnetosonic waves exhibit dispersion and damping in RMHD plasma. It is also revealed that mode conversion between fast and slow RMHD waves occurs at specific values of the wavenumber and propagation angle. The investigation extends to exploring the influence of various parameters characterizing radiative plasma, such as radiation pressure, plasma beta, and radiation diffusivity, on the dispersion and damping of magnetosonic modes (both fast and slow) in RMHD plasma. The findings are elucidated through numerical illustrations. The proposed model finds application in scenarios involving optically thick regions within stars, specifically in their inner atmosphere and interior region. In these regions, the transport of radiation adheres to equilibrium diffusion, and radiation pressure and energy density reach magnitudes comparable to thermal energy and pressure.
S-band acoustoelectric amplifier in an InGaAs-AlScN-SiC architecture
Authors: Hackett L. , Du X. , Miller M. , Smith B. , Santillan S. , Montoya J. , Reyna R. , Arterburn S. , Weatherred S. , Friedmann T. A. , Olsson R. H. , Eichenfield M.
Published: March 2024

Here, we report on an acoustoelectric slab waveguide heterostructure for phonon amplification using a thin Al0.58Sc0.42N film grown directly on a 4H-SiC substrate with an ultra-thin In0.53Ga0.47As epitaxial film heterogeneously integrated onto the surface of the Al0.58Sc0.42N. The aluminum scandium nitride film grown directly on silicon carbide enables a thin (∼850 nm thick) piezoelectric film to be deposited on a thermally conductive bulk substrate (370 W/m K for 4H-SiC); the high thermal conductivity of the substrate, large mobility of the semiconductor (∼7000 cm2/V s), and low carrier concentration (∼5 × 1015 cm−3) yield low self-heating. A Sezawa mode with optimal overlap between the peak of its evanescent electric field and the semiconductor charge carriers is supported. The high velocity of the heterostructure materials allows us to operate the Sezawa mode amplifier at 3.05 GHz, demonstrating a gain of 500 dB/cm (40 dB in 800 μm). Additionally, a terminal end-to-end radio frequency gain of 7.7 dB and a nonreciprocal transmission of 52.6 dB are achieved with a dissipated DC power of 2.3 mW. The power added efficiency and acoustic noise figure are also characterized.
1D graphene nanoribbons-mediated defect engineering in 2D MXene for high-performance supercapacitors
Authors: Mahajan Parika , Sardana Sagar , Mahajan Aman
Published: March 2024

Carbon-based supercapacitors have been extensively explored by the virtue of their exceptional performance in terms of charge-storage capacity, electrical conductivity, and good stability. However, the rush to find potential approaches for increasing their specific capacitance and specific energy without adversely affecting the specific power is still exciting. Herein, we synthesized hierarchically structured carbon-based composites based on 2D MXene sheets with an interconnected conductive porous network of 1D graphene nanoribbons (GNRs). Synergistic effects arising due to the defect engineering of 2D MXene sheets with 1D GNRs led to high surface-area, effective ion-transport, and improved structural robustness of the composite electrodes, thereby enhancing the specific capacitance along with specific energy of device while preserving its specific power. The electrochemical studies revealed that the composites with 1 wt.% GNRs (GMX-B) outperformed when the composition of GNRs was varied from 0.5 to 1.5 wt. % in MXene (GMX-A, GMX-B, and GMX-C). In comparison to pristine MXene and pristine GNRs, GMX-B exhibited ∼2.54 and ∼2.74 folded higher capacitance of 238.96 F/g at 0.6 A/g current density, respectively, a higher capacitance retention of 72.16% for a scan rate from 10–140 mV/s as well as a good cyclic stability of 85.11% over 10 000 charge/discharge cycles. Furthermore, GMX-B electrode achieved a high specific energy of 4.066 Wh/Kg while maintaining a specific power of 210.640 W/Kg as compared to pristine MXene (1.597 Wh/Kg at 211.989 W/Kg) and pristine GNRs (1.482 Wh/Kg at 211.089 W/Kg). Thus, we anticipated that the use of hierarchically engineered 1D/2D carbon-based composites with considerable improvement in its interfacial properties holds great potential to achieve high-performing energy-storage devices.
Impact of flow intermittency on heat transfer enhancement in serpentine channels
Authors: Xiong Guanqing , Wang Zhaoguang
Published: March 2024

With liquid cold plates being widely applied in industries such as battery energy storage systems, advanced heat transfer enhancement technologies are urgently needed to efficiently dissipate the ever-increasing heat load. The present work numerically and experimentally explores the potential of flow intermittency in a laminar serpentine channel for thermal performance improvement. The numerical analysis shows that the dynamic Dean vortex evolution induced by the intermittent mainstream disrupts the thermal boundary layer more effectively than the steady-flow vortices and enhances local Nusselt number at the U-turns by 117% maximally. Such secondary vortices are transported intermittently to the straight segments, resulting in a 55% increase in the area-averaged heat transfer by promoting mainstream-boundary flow mixing. The optimization of the flow intermittency profile is achieved by matching the pulse-on and deceleration stage durations with the characteristic times of secondary vortex growth and transport. The numerical results are qualitatively validated by the experimental measurement conducted in a water bath. The current study novelly demonstrates the design concept of enhancing heat transfer in curved channels by actively controlling the intermittent flow and proposes the design criteria for the intermittency profile to achieve optimal performance.
Asymmetrical positioning of cell organelles reflects the cell chirality of mouse myoblast cells
Authors: Hachem Zeina , Hadrian Courtney , Aldbaisi Lina , Alkaabi Muslim , Wan Leo Q. , Fan Jie
Published: March 2024

Cell chirality is crucial for the chiral morphogenesis of biological tissues, yet its underlying mechanism remains unclear. Cell organelle polarization along multiple axes in a cell body, namely, apical–basal, front–rear, and left–right, is known to direct cell behavior such as orientation, rotation, and migration. Among these axes, the left–right bias holds significant sway in determining the chiral directionality of these behaviors. Normally, mouse myoblast (C2C12) cells exhibit a strong counterclockwise chirality on a ring-shaped micropattern, whereas they display a clockwise dominant chirality under Latrunculin A treatment. To investigate the relationship between multicellular chirality and organelle positioning in single cells, we studied the left–right positioning of cell organelles under distinct cell chirality in single cells via micropatterning technique, fluorescent microscopy, and imaging analysis. We found that on a “T”-shaped micropattern, a C2C12 cell adopts a triangular shape, with its nucleus–centrosome axis pointing toward the top-right direction of the “T.” Several other organelles, including the Golgi apparatus, lysosomes, actin filaments, and microtubules, showed a preference to polarize on one side of the axis, indicating the universality of the left–right asymmetrical organelle positioning. Interestingly, upon reversing cell chirality with Latrunculin A, the organelles correspondingly reversed their left–right positioning bias, as suggested by the consistently biased metabolism and contractile properties at the leading edge. This left–right asymmetry in organelle positioning may help predict cell migration direction and serve as a potential marker for identifying cell chirality in biological models.
Inverse design method of thermal devices with thermal Hall effect
Authors: Sato Yuki , Deguchi Teppei , Nomura Tsuyoshi , Dede Ercan M. , Kawamoto Atsushi
Published: March 2024

Efficient thermal management is important for both performance and efficiency improvements of thermal devices. For designing reasonable materials and structures of such devices, various design methods were proposed where the material thermal conductivity tensors were positive definite and symmetric based on the physical requirements. Here, we propose an inverse design method for thermal devices considering the thermal Hall effect, which makes the material thermal conductivity tensor asymmetric. Enlarging the design space consisting of the symmetric constitutive tensors to that of the asymmetric ones, there is a possibility of improving the theoretical performance limit of thermal devices. We formulate an inverse problem based on the free material optimization formalism, parameterizing the design space so that the physically available property could be naturally satisfied. Several numerical experiments are provided to show the validity and the utility of the proposed method.
A novel digital intermediate frequency module for hyperspectral microwave radiometers based on the parallel fast Fourier transform algorithm
Authors: Gong Xun , Tong Ling , Gao Bo , Wang Peicheng , Gao Xinyi
Published: March 2024

Microwave radiometers, possessing all-day and all-weather operational capabilities, are extensively utilized in the exploration of planetary atmospheres and surfaces. The potential of the hyperspectral detection technology to enhance the precision and resolution of microwave radiometer detection has made it a crucial research focus. This paper introduces an intermediate frequency (IF) module for hyperspectral microwave radiometers. The IF module is constructed with two 6.4 gigabit samples per second sampling-rate analog-to-digital converter (ADC) chips and a Xilinx Virtex-7 field programmable gate array. By implementing a parallel fast Fourier transform algorithm and a pipeline architecture, the IF module can efficiently process all ADC sampling data in real-time, generating 512 channels of output for each ADC. The test results, including linearity, sensitivity, and flatness, are presented and thoroughly analyzed for the IF module. Furthermore, the module is interfaced with the radio frequency front-end of the microwave radiometer to measure hot and cold calibration sources and assess its sensitivity. When combined with a suitable front-end receiver, the IF module can form a radiometer system suitable for various applications of microwave remote sensing.
Reducing the time-step errors in diffusion Monte Carlo
Authors: Anderson Tyler A. , Per Manolo C. , Umrigar C. J.
Published: March 2024

We modify the reweighting factor of the projector used in diffusion Monte Carlo to reduce the time-step error of the total energy. Furthermore, we present a reweighting scheme that has the desirable feature that it is exactly size-consistent, i.e., the energy of a system containing widely separated fragments is the same as the sum of the energies of the individual fragments. The practical utility of the latter improvement is that it reduces the time-step error of the binding energies of some weakly interacting systems.
Opto-electrochemical variation with gel polymer electrolytes in transparent electrochemical capacitors for ionotronics
Authors: Kumar Chandini , Sebastian Arun K. , Markapudi Prasutha Rani , Beg Mustehsan , Sundaram Senthilarasu , Hussain Amir , Manjakkal Libu
Published: March 2024

Advanced flexible ionotronic devices have found excellent applications in the next generation of electronic skin (e-skin) development for smart wearables, robotics, and prosthesis. In this work, we developed transparent ionotronic-based flexible electrochemical capacitors using gel electrolytes and indium tin oxide (ITO) based transparent flexible electrodes. Different gel electrolytes were prepared using various salts, including NaCl, KCl, and LiCl in a 1:1 ratio with a polyvinyl alcohol (PVA) solution and compared its electrochemical performances. The interaction between gel electrolytes and ITO electrodes was investigated through the development of transparent electrochemical capacitors (TEC). The stable and consistent supply of ions was provided by the gel, which is essential for the charge storage and discharge within the TEC. The total charge contribution of the developed TECs is found from the diffusion-controlled mechanism and is measured to be 4.59 mC cm−2 for a LiCl/PVA-based gel. The prepared TEC with LiCl/PVA gel electrolyte exhibited a specific capacitance of 6.61 mF cm−2 at 10 μA cm−2. The prepared electrolyte shows a transparency of 99% at 550 nm and the fabricated TEC using LiCl/PVA gel exhibited a direct bandgap of 5.34 eV. The primary benefits of such ionotronic-based TEC development point to its potential future applications in the manufacturing of transparent batteries, electrochromic energy storage devices, ionotronic-based sensors, and photoelectrochemical energy storage devices.
Study on the effects of Si-doping in molecular beam heteroepitaxial β-Ga2O3 films
Authors: Zhan Jiali , Wu Ying , Zeng Xiaohong , Feng Boyuan , He Minghao , He Gaohang , Ding Sunan
Published: March 2024

β-Ga2O3, an emerging wide bandgap semiconductor material, holds significant potential for various applications. However, challenges persist in improving the crystal quality and achieving controllable doping of β-Ga2O3. In particular, the relationship between these factors and the mechanisms behind them are not fully understood. Molecular beam epitaxy (MBE) is viewed as one of the most sophisticated techniques for growing high-quality crystalline films. It also provides a platform for studying the effects of doping and defects in heteroepitaxial β-Ga2O3. In our study, we tackled the issue of Si source passivation during the MBE growth of Si-doped β-Ga2O3. We did this by using an electron beam vaporize module, a departure from the traditional Si effusion cell. Our research extensively explores the correlation between Si doping concentration and film properties. These properties include microstructure, morphology, defects, carrier conductivity, and mobility. The results from these investigations are mutually supportive and indicate that a high density of defects in heteroepitaxial β-Ga2O3 is the primary reason for the challenges in controllable doping and conductivity. These insights are valuable for the ongoing development and enhancement of β-Ga2O3-based device techniques.
Field-free switching in perpendicular Ta/CoFeB/MgO multilayers achieved by annealing temperature gradient
Authors: Wang Shuanghai , Dai Xingze , He Kun , Wang Jin , Zhang Xiaolong , Guo Qixun , Feng Guanqun , Xu Yongkang , Deng Yafeng , Liu Ruobai , Du Jun , Wang Yong-Lei , Wang Chao , Xu Yongbing , He Liang
Published: March 2024

Current flowing through heavy metals generates spin current by the spin Hall effect (SHE), and spin current exerts a torque on the adjacent magnetic layer, thereby switching the magnetization direction of the magnetic layer. Normally, an external magnetic field must be used to break symmetry in the response to the SHE torque, to realize deterministic switching. However, the presence of magnetic fields increases the difficulty in integrating spintronic devices with complementary metal-oxide-semiconductor. Thus, field-free spin–orbit torque switching has been a research hotspot. Here, symmetry-breaking has been realized by tilting the sample during the annealing process, resulting in a non-uniform diffusion of Ta atoms in the samples along the temperature gradient (x-direction), which was confirmed by transmission electron microscope mapping. As a result, the sample has demonstrated deterministic switching, in the absence of an external magnetic field, with a switching ratio of up to 88% and the critical current density of 1.5 × 107 A/cm2. Tilting annealing is a simple approach to achieve field-free switching.
Integration of low-thermal-budget In2O3 NMOS inverter and GaN HEMT for power electronics
Authors: Kumar Mritunjay , Yuvaraja Saravanan , Xiao Na , Rajbhar Manoj Kumar , Mainali Ganesh , Khandelwal Vishal , Tang Xiao , Li Xiaohang
Published: March 2024

Herein, we demonstrated an “interposer”-style integration of In2O3 FET-based gate-driver circuitry wire bonded to an AlGaN/GaN high electron mobility transistor (HEMT) device grown on a GaN-on-Si substrate, and its feasibility for power electronics was discussed. The normally-on AlGaN/GaN HEMT exhibited a threshold voltage of −2.8 V, with a maximum drain current density of 265 mA/mm. The device also showed good off-state performance, such as a high ON/OFF ratio (Ion/Ioff) of ∼1010 with a breakdown voltage of ∼445 V and an off-state leakage current of ∼10−12 A. The low-temperature processed In2O3 driver circuitry exhibited a high gain of ∼64 and a maximum operating frequency of 2 kHz. The temperature-dependent study of the voltage transfer characteristics (VTC) of In2O3 driver circuitry exhibited stable operation up to 125 °C. An integrated In2O3 driver circuitry with GaN HEMT was demonstrated, marked by a 50 mA/mm drain current for circuit response of one cycle during the ON state. These results pave the way for future monolithic integration of oxide semiconductor-based gate-driver circuitry with power switches for energy-efficient integrated circuits.
Exploring challenges and potential for a commercially viable piezoelectric energy harvesting system—Can Energy-as-Data concept thrive?
Authors: Bai Yang
Published: March 2024

Over the past two decades, piezoelectric energy harvesting systems have undergone extensive research, spanning from materials to devices and electronics. Recently, there has been a notable introduction of the term “self-powered sensors,” which essentially refers to conventional, older passive sensors, associated with piezoelectric (or triboelectric) nanogenerators. Unfortunately, neither approach has yet yielded a successful market example. The primary challenge seems to lie in the intermittent nature of ambient kinetic energy input to these harvesters, despite the high output power density of piezoelectric energy harvesters. This article emphasizes the concept of Energy-as-Data, holding promise for a potentially brighter future for commercializable piezoelectric energy harvesting systems. The key advantage offered by this concept is the substantial extension of battery life through the optimization of data acquisition protocols. This involves transitioning from the traditional passive sensing mode with a high sampling rate to an extremely low duty cycle. This transition allows the harvested energy, accumulated in an energy storage unit over a specific interval, to be translated into critical information regarding kinetic environmental changes during that period. The article also discusses the broader context that necessitates the Energy-as-Data concept, establishing it as one of the few viable pathways to cultivate specialized markets for piezoelectric energy harvesting.
Spatiotemporal theory of a gyrotron based on a three-mirror cavity
Authors: Novak E. M. , Savilov A. V.
Published: March 2024

We present the quasi-analytical spatiotemporal theory of the resonant traveling-wave tube scheme of a gyrotron based on the transverse amplifications of the operating wave and on the use of a remote delayed feedback. The main idea is to implement a system with a dense spectrum of eigenmodes, which makes it possible to smoothly adjust the generation frequency by switching from mode to mode when the operating magnetic field changes. On the basis of a simple 2D three-mirror model, we show the possibility of achieving the stable single-frequency generation regime in this system if the excess of the operating current above the starting threshold is not too high. The mechanism of loss of stability of the single-frequency generation with an increase in operating current is also described.
Cracking process and microstructural characteristics of granite under heating–cooling alternations
Authors: Long Kun , Wei Qike , Peng Kang , Wu Yang , Luo Song , Cheng Yugang , Li Lei
Published: March 2024

Studying the damage correlation mechanism of rocks subjected to heating–cooling alternations is of important significance for deeply understanding the permeability increase mechanism of reservoirs during heat extraction from hot dry rocks and assessing the reservoir stability. By carrying out the uniaxial compression test, Brazilian splitting test, nuclear magnetic resonance test, and scanning electron microscopy test on granite after heating–cooling alternations, the evolution laws of physical and mechanical properties as well as the microstructures of granite were studied. In addition, the multi-scale response characteristics and the damage correlation mechanism of granite after heating–cooling alternations were analyzed. Research results show that, when the heat treatment temperature rises to 600 °C, the physical and mechanical parameters, including the wave velocity, strength, and elastic modulus, reduce abruptly. The heat treatment temperature exerts more significant influences on the physical and mechanical properties of the granite than the heating–cooling alternation cycles. Both the temperature and alternation cycles are beneficial to the microcrack development and propagation, while the temperature more significantly affects the development degree of microcracks. Under the external load, the microscopic defects in the granite after heating–cooling alternations guide the propagation of macrocracks and cause more serious damage to the microstructures in the granite, exhibiting more complex failure modes. The results provide a theoretical basis for fracturing technology and stability evaluation of high-temperature reservoirs.
Phase-space evolution of quasiparticle excitations in electron gas
Authors: Akbari-Moghanjoughi M.
Published: March 2024

In this research, we use the dual lengthscale quasiparticle model for collective quantum excitations in electron gas to study the time evolution of the Wigner function. The linearized time-dependent Schrödinger–Poisson system for quasiparticles is used to study the dynamics of initial known stationary and damped solutions in an electron gas with arbitrary degree of degeneracy. The self-consistent potential in the Schrödinger–Poisson model is treated in a quite different manner in this analysis due to the effective coupling of the electrostatic field to the electron density, which leads to a modified Wigner function. It is shown that the modified Wigner function in the absence of external potential evolves similar to the system of free particles, a feature of collective quantum excitations which is quite analogous to freely evolving classical system of particles in the center of mass frame in the absence of external forces. The time evolution of the modified Wigner function reveals a grinding effect on large-amplitude density structures present at initial states, which is a characteristic feature of the Landau damping in plasmas. It is further shown that linear phase-space dynamics of spill-out electrons (damped quasiparticles) can be described similar to free quasiparticles with imaginary momentum. The later predicts the surface electron tunneling via the collective excitations of spill-out electrons at the half-space boundary, which is closely related to the Heisenberg's uncertainty principle. Current research can have applications in plasmonics and related fields.
A perturbation approach to study the shock wave propagation in a non-ideal magnetogasdynamics under isothermal condition
Authors: Yadav Shalini , Singh Deepika , Arora Rajan
Published: March 2024

The main goal of this paper is to obtain a global solution to the problem of imploding strong cylindrical shock waves (SWs) collapsing at the axis of symmetry in a non-ideal gas under the influence of an axial magnetic field using the perturbation series technique. This global solution is valid for the entire flow field up to the instant of collapse. Guderley's asymptotic solution, which is only applicable in the neighborhood of the axis of implosion, is properly reproduced by this global solution. Guderley's local self-similar solution allows for the determination of the first dominant similarity exponent only; however, this approach also enables the identification of additional, less dominant similarity exponents along with the corresponding amplitudes. Additionally, the computed values of the similarity exponents have been compared with the results drawn from Guderley's approach. The profiles of fluid variables and shock trajectory are shown graphically for different values of the non-ideal parameter, adiabatic index, and shock Cowling number. The “Mathematica” software has been used to do all numerical computations.
Flow control by dielectric barrier discharge plasma actuators for a rectangular jet with inlet disturbance
Authors: Lee Keunseob , Kikuchi Satoshi
Published: March 2024

Direct numerical simulations were performed to examine the control mechanism of a plasma actuator using a dielectric barrier discharge in a rectangular jet with an inlet disturbance. The nozzle has a ratio of 75–10 mm, while the Reynolds number is 3300, and the peak frequency near the nozzle exit is 55 Hz. The jet is controlled by the actuators with conditions of 55 Hz burst frequency, 10% duty ratio, and π phase difference between the upper and lower actuators. The flow field spreads downstream more than that without control. Moreover, the controlling mechanism generates a vortex by inducing flow from the actuator, which grows in size by merging with other vortices generated upstream. Furthermore, the induced flows generate vortices on the upper and lower shear layers that grow in opposite phases of π, and these vortices cause upward and downward flow, respectively, thereby accelerating the spread of the jet. The vortex generated by the induced flow can grow due to its low-streamwise velocity. This occurs regardless of the inlet disturbance because the streakline from the induced flow moves downward near the nozzle surface, causing a rapid decrease in the streamwise velocity after the actuator is stopped. Thus, the actuator's control effect can be explained by the momentary change in the location of the streaklines around it.
Peristaltic transport of viscoelastic fluid in curved ducts with ciliated walls
Authors: Abbasi Aamar , Danish Sherjeel , Farooq Waseh , Khan M. Ijaz , Akermi Mehdi , Hejazi Hala A
Published: March 2024

The transport of complex rheological fluids in physiological ducts is often facilitated by the dynamic phenomenon of peristalsis. Additionally, peristaltic transport assisted by cilia plays a significant role in various natural processes such as respiration, circulation, locomotion, and reproduction. This study focuses on magnetically induced flow bounded by non-uniform curved walls, motivated by the importance of peristalsis and micro-organism motility. To characterize the complex rheology of the fluid liner, a viscoelastic model described by the constitutive equation of Jeffrey's fluid is employed. The flow problem is mathematically formulated using curvilinear coordinates. Subsequently, linear transformations and scaling factors are applied to convert the equations into dimensionless form, while considering biotic restrictions such as creeping transport and long wavelength to reduce dependent variables. By utilizing the stream function and cross-differentiation, a fourth-order equation is obtained and numerically approximated using the shooting method. The effects of various parameters on the flow are illustrated through graphs, and a physical interpretation of the graphical results is provided. It is observed that ciliated walls of the channel enhance the velocity and pumping, while trapping phenomena are more pronounced in a non-uniform channel compared to a uniform channel.
Empirical test of the Kelvin relation in thermoelectric nanostructures
Authors: Panthi Hari Prasad , Dhawan Ruchika , Edwards Hal , Lee Mark
Published: March 2024

Thermoelectric (TE) nanostructures with dimensions of ∼100 nm can show substantially better TE properties compared to the same material in the bulk form due to charge and heat transport effects specific to the nanometer scale. However, TE physics in nanostructures is still described using the Kelvin relation (KR) Π = αT, where Π is the Peltier coefficient, α the thermopower, and T the absolute temperature, even though derivation of the KR uses a local equilibrium assumption (LEA) applicable to macroscopic systems. It is unclear whether nanostructures with nanostructures with dimensions on the order of an inelastic mean free path satisfy a LEA under any nonzero temperature gradient. Here, we present an experimental test of the KR on a TE system consisting of doped silicon-based nanostructures with dimensions comparable to the phonon–phonon and electron–phonon mean-free-paths. Such nanostructures are small enough that true local thermodynamic equilibrium may not exist when a thermal gradient is applied. The KR is tested by measuring the ratio Π/α under various applied temperature differences and comparing it to the average T. Results show relative deviations from the KR of |(Π/α)/T − 1| ≤ 2.2%, within measurement uncertainty. This suggests that a complete local equilibrium among all degrees of freedom may be unnecessary for the KR to be valid but could be replaced by a weaker condition of local equilibrium among only charge carriers.
Stability analysis of synchronization in long-range temporal networks using theory of dichotomy
Authors: Rakshit Sarbendu , Majhi Soumen , Ghosh Dibakar
Published: March 2024

Most of the previous studies on the stability analysis of synchronization in static or time-varying networks are based on the master stability function approach, which is a semi-analytical concept. The necessary and sufficient conditions for synchronization in time-varying networks are challenging problems since the last few years. We focus on the stability analysis of synchronization in time-varying networks, particularly long-range networks. The use of dichotomy theory to derive sufficient conditions for synchronization in this context is an interesting approach. The incorporation of long-range interactions adds complexity and might lead to larger regions of synchronization, providing valuable insights into the dynamics of such networks. Analyzing the co-action of the time-varying nature in the network topology and long-range interactions is a relevant and challenging task, especially when the network is not synchronized. This work appears to explore the interplay between these factors and their impact on synchronization. Additionally, the numerical study considering long-range connections governed by a power-law within the framework of an Erdös–Rényi random network is a practical way to validate and test the analytical results. It is good to see that we are exploring the effects of varying parameters such as rewiring probability, coupling strength, and power-law exponent on the synchronization state.
Elucidating genotype × environment interactions for grain iron and zinc content in a subset of pearl millet (Pennisetum glaucum) recombinant inbred lines
Authors: Singhal Tripti , Satyavathi C. Tara , Singh S. P. , Sankar Mukesh , M. Mallik , R. Thribhuvan , Yadav Sunaina , Bharadwaj C.
Published: March 2024

Context Micronutrient enrichment of pearl millet (Pennisetum glaucum (L.) R.Br.), an important food source in arid and semi-arid Asia and Africa, can be achieved by using stable genotypes with high iron and zinc content in breeding programs. Aims We aimed to identify stable expression of high grain iron and zinc content in pearl millet lines across environments. Methods In total, 29 genotypes comprising 25 recombinant inbred lines (RILs), two parental lines and two checks were grown and examined from 2014 to 2016 in diverse environments. Best performing genotypes were identified through genotype + genotype × environment interaction (GGE) biplot and additive main-effects and multiplicative interaction (AMMI) model analysis. Key results Analysis of variance showed highly significant (P < 0.01) variations. The GGE biplot accounted for 87.26% (principal component 1, PC1) and 9.64% (PC2) of variation for iron, and 87.04% (PC1) and 6.35% (PC2) for zinc. On the basis of Gollob’s F validation test, three interaction PCs were significant for both traits. After 1000 validations, the real root-mean-square predictive difference was computed for model diagnosis. The GGE biplot indicated two winning RILs (G4, G11) across environments, whereas AMMI model analysis determined 10 RILs for iron (G12, G23, G24, G7, G15, G13, G25, G11, G4, G22) for seven for zinc (G14, G15, G4, G7, G11, G4, G26) as best performers. The most stable RILs across environments were G12 for iron and G14 for zinc. Conclusions High iron and zinc lines with consistent performance across environments were identified and can be used in the development of biofortified hybrids. Implications The findings suggest that AMMI and GGE, as powerful and straightforward techniques, may be useful in selecting better performing genotypes.
SRF transcriptionally regulates the oligodendrocyte cytoskeleton during CNS myelination
Authors: Iram Tal , Garcia Miguel A. , Amand Jérémy , Kaur Achint , Atkins Micaiah , Iyer Manasi , Lam Mable , Ambiel Nicholas , Jorgens Danielle M. , Keller Andreas , Wyss-Coray Tony , Kern Fabian , Zuchero J. Bradley
Published: March 2024

Myelination of neuronal axons is essential for nervous system development. Myelination requires dramatic cytoskeletal dynamics in oligodendrocytes, but how actin is regulated during myelination is poorly understood. We recently identified serum response factor (SRF)—a transcription factor known to regulate expression of actin and actin regulators in other cell types—as a critical driver of myelination in the aged brain. Yet, a major gap remains in understanding the mechanistic role of SRF in oligodendrocyte lineage cells. Here, we show that SRF is required cell autonomously in oligodendrocytes for myelination during development. Combining ChIP-seq with RNA-seq identifies SRF-target genes in oligodendrocyte precursor cells and oligodendrocytes that include actin and other key cytoskeletal genes. Accordingly, SRF knockout oligodendrocytes exhibit dramatically reduced actin filament levels early in differentiation, consistent with its role in actin-dependent myelin sheath initiation. Surprisingly, oligodendrocyte-restricted loss of SRF results in upregulation of gene signatures associated with aging and neurodegenerative diseases. Together, our findings identify SRF as a transcriptional regulator that controls the expression of cytoskeletal genes required in oligodendrocytes for myelination. This study identifies an essential pathway regulating oligodendrocyte biology with high relevance to brain development, aging, and disease.
Neuronal IL-17 controls
Caenorhabditis elegans
developmental diapause through CEP-1/p53
Authors: Godthi Abhishiktha , Min Sehee , Das Srijit , Cruz-Corchado Johnny , Deonarine Andrew , Misel-Wuchter Kara , Issuree Priya D. , Prahlad Veena
Published: March 2024

During metazoan development, how cell division and metabolic programs are coordinated with nutrient availability remains unclear. Here, we show that nutrient availability signaled by the neuronal cytokine, ILC-17.1, switches
Caenorhabditis elegans
development between reproductive growth and dormancy by controlling the activity of the tumor suppressor p53 ortholog, CEP-1. Specifically, upon food availability, ILC-17.1 signaling by amphid neurons promotes glucose utilization and suppresses CEP-1/p53 to allow growth. In the absence of ILC-17.1, CEP-1/p53 is activated, up-regulates cell-cycle inhibitors, decreases phosphofructokinase and cytochrome C expression, and causes larvae to arrest as stress-resistant, quiescent dauers. We propose a model whereby ILC-17.1 signaling links nutrient availability and energy metabolism to cell cycle progression through CEP-1/p53. These studies describe ancestral functions of IL-17 s and the p53 family of proteins and are relevant to our understanding of neuroimmune mechanisms in cancer. They also reveal a DNA damage–independent function of CEP-1/p53 in invertebrate development and support the existence of a previously undescribed
C. elegans
dauer pathway.
East Asian summer monsoon delivers large abundances of very short-lived organic chlorine substances to the lower stratosphere
Authors: Pan Laura L. , Atlas Elliot L. , Honomichl Shawn B. , Smith Warren P. , Kinnison Douglas E. , Solomon Susan , Santee Michelle L. , Saiz-Lopez Alfonso , Laube Johannes C. , Wang Bin , Ueyama Rei , Bresch James F. , Hornbrook Rebecca S. , Apel Eric C. , Hills Alan J. , Treadaway Victoria , Smith Katie , Schauffler Sue , Donnelly Stephen , Hendershot Roger , Lueb Richard , Campos Teresa , Viciani Silvia , D’Amato Francesco , Bianchini Giovanni , Barucci Marco , Podolske James R. , Iraci Laura T. , Gurganus Colin , Bui Paul , Dean-Day Jonathan M. , Millán Luis , Ryoo Ju-Mee , Barletta Barbara , Koo Ja-Ho , Kim Joowan , Liang Qing , Randel William J. , Thornberry Troy , Newman Paul A.
Published: March 2024

Deep convection in the Asian summer monsoon is a significant transport process for lifting pollutants from the planetary boundary layer to the tropopause level. This process enables efficient injection into the stratosphere of reactive species such as chlorinated very short-lived substances (Cl-VSLSs) that deplete ozone. Past studies of convective transport associated with the Asian summer monsoon have focused mostly on the south Asian summer monsoon. Airborne observations reported in this work identify the East Asian summer monsoon convection as an effective transport pathway that carried record-breaking levels of ozone-depleting Cl-VSLSs (mean organic chlorine from these VSLSs ~500 ppt) to the base of the stratosphere. These unique observations show total organic chlorine from VSLSs in the lower stratosphere over the Asian monsoon tropopause to be more than twice that previously reported over the tropical tropopause. Considering the recently observed increase in Cl-VSLS emissions and the ongoing strengthening of the East Asian summer monsoon under global warming, our results highlight that a reevaluation of the contribution of Cl-VSLS injection via the Asian monsoon to the total stratospheric chlorine budget is warranted.