bluuebunny/crossref_metadata_2025 huggingface dataset:
Deep learning architecture for sparse and noisy turbulent flow data
Authors: Sofos Filippos , Drikakis Dimitris , Kokkinakis Ioannis William
Published: March 2024

The success of deep learning models in fluid dynamics applications will depend on their ability to handle sparse and noisy data accurately. This paper concerns the development of a deep learning model for reconstructing turbulent flow images from low-resolution counterparts encompassing noise. The flow is incompressible through a symmetric, sudden expansion featuring bifurcation, instabilities, and turbulence. The deep learning model is based on convolutional neural networks, in a high-performance, lightweight architecture. The training is performed by finding correlations between high- and low-resolution two-dimensional images. The study also investigates how to remove noise from flow images after training the model with high-resolution and noisy images. In such flow images, the turbulent velocity field is represented by significant color variations. The model's peak signal-to-noise ratio is 45, one of the largest achieved for such problems. Fine-grained resolution can be achieved using sparse data at a fraction of the time required by large-eddy and direct numerical simulation methods. Considering its accuracy and lightweight architecture, the proposed model provides an alternative when repetitive experiments are complex and only a small amount of noisy data is available.
Nature and energetics of low-lying excited singlets/triplets and intersystem crossing rates in selone analogs of perylenediimide: A theoretical perspective
Authors: Tedy Annette Mariya , Manna Arun K.
Published: March 2024

The structural rigidity and chemical diversity of the highly fluorescent perylenediimide (PDI) provide wide opportunities for developing triplet photosensitizers with sufficiently increased energy efficiency. Remarkably high intersystem crossing (ISC) rates with a complete fluorescence turn-off reported recently for several thione analogs of PDI due to substantially large spin–orbit coupling garners huge attention to develop other potential analogs. Here, several selone analogs of PDI, denoted as mSe-PDIs (m = 1–4) with varied Se content and positions, are investigated to provide a comprehensive and comparative picture down the group-16 using density functional theory (DFT) and time-dependent DFT implementing optimally tuned range-separated hybrid in toluene dielectric. All mSe-PDIs are confirmed to be dynamically stable and also thermodynamically feasible to synthesize from their oxygen and thione congeners. The first excited-state singlet (S1) of mSe-PDI with relatively low Se-content (m = 1, 2) is of nπ* character with an expected fluorescence turn-off. Whereas, the ππ* nature of the S1 for 3Se-PDI and 4Se-PDI suggests a possible fluorescence turn-on in the absence of any other active nonradiative deactivation pathways. However, ∼4–6 orders greater ISC rates (∼1012–1014 s−1) than the fluorescence ones (∼108 s−1) for all mSe-PDIs signify highly efficient triplet harvest. Importantly, significantly higher ISC rates for these mSe-PDIs than their thione congeners render them efficient triplet photosensitizers.
Vapor compression and energy dissipation in a collapsing laser-induced bubble
Authors: Preso D. B. , Fuster D. , Sieber A. B. , Obreschkow D. , Farhat M.
Published: March 2024

The composition of the gaseous phase of cavitation bubbles and its role on the collapse remains to date poorly understood. In this work, experiments of single cavitation bubbles in aqueous ammonia serve as a novel approach to investigate the effect of the vapor contained in a bubble on its collapse. We find that the higher vapor pressure of more concentrated aqueous ammonia acts as a resistance to the collapse, reducing the total energy dissipation. In line with visual observation, acoustic measurements, and luminescence recordings, it is also observed that higher vapor pressures contribute to a more spherical collapse, likely hindering the growth of interface instabilities by decreasing the collapse velocities and accelerations. Remarkably, we evidence a strong difference between the effective damping and the energy of the shock emission, suggesting that the latter is not the dominant dissipation mechanism at collapse as predicted from classical correction models accounting for slightly compressible liquids. Furthermore, our results suggest that the vapor inside collapsing bubbles gets compressed, consistently with previous studies performed in the context of single bubble sonoluminescence, addressing the question about the ability of vapors to readily condense during a bubble collapse in similar regimes. These findings provide insight into the identification of the influence of the bubble content and the energy exchanges of the bubble with its surrounding media, eventually paving the way to a more efficient use of cavitation in engineering and biomedical applications.
Electronic and optical properties of pyrochlore Re2Ti2O7 (Re  = Sm and Eu) from first-principles
Authors: Liu Wan-Qi , Lu Hong-Ting , Li Yan-Lu , Zhao Xian , Wang Chun-Ming
Published: March 2024

Rare-earth titanate oxides are believed to be prospective functional materials for photocatalytic and photoluminescent applications because of their excellent optical properties and thermal stability of their physical properties. However, the relationships between optical properties and photoelectron trapping mechanisms are unclear. Herein, the structure, electronic, and optical properties of pyrochlore-structure Re2Ti2O7 (Re = Sm and Eu) were investigated using the first-principles approach with the Hubbard parameter U (GGA + U). The calculated bandgap is 2.5 eV for Sm2Ti2O7 and 2.4 eV for Eu2Ti2O7, which is in good agreement with the experimental observation. The results indicate that the strongly localized f states at the top of valence band are charge-trapping sites for photoexcitation of Re2Ti2O7, where electrons can absorb photon energy and transfer from the valence band to the conduction band, resulting in the photocatalytic and/or fluorescent effects in the visible and early UV regions. The important optical parameters, dielectric function ε(ω), refractive index n(ω), extinction coefficient k(ω), reflectivity R(ω), absorption coefficient I(ω), optical conductivity σ(ω), and electron energy-loss L(ω) were studied in detail, indicating that these optical parameters of Sm2Ti2O7 and Eu2Ti2O7 are insensitive to the ultra-violet (UV) radiation, but both Sm2Ti2O7 and Eu2Ti2O7 exhibit excellent optical properties in the visible and early UV regions. This work provides a clear understanding on the photoelectron trapping mechanism of pyrochlore-structure Re2Ti2O7, which will help to improve the photocatalytic and photoluminescent performance of Re2Ti2O7 and broaden their applications.
SiC-based high electron mobility transistor
Authors: Sazawa Hiroyuki , Nakajima Akira , Kuboya Shigeyuki , Umezawa Hitoshi , Kato Tomohisa , Tanaka Yasunori
Published: March 2024

This paper describes the fabrication of a SiC-based high electron mobility transistor (HEMT). A single-crystal 3C–SiC layer was grown on a C-face 4H–SiC substrate, and 2D electron gas was induced at the 3C–SiC/4H–SiC heterointerface due to the unique polarization physics. The measured Hall mobility of the 2DEG was 586 cm2/V s at room temperature. Source, gate, and drain electrodes were fabricated on the 3C–SiC surface. The drain current for the fabricated SiC-HEMT was measured to be 47.5 mA/mm, and the transconductance was estimated to be 13.5 mS/mm.
Introduction to the Australian Fire Danger Rating System†
Authors: Hollis Jennifer J. , Matthews Stuart , Fox-Hughes Paul , Grootemaat Saskia , Heemstra Simon , Kenny Belinda J. , Sauvage Sam
Published: March 2024

Background Fire danger rating systems are used daily across Australia to support fire management operations and communications to the general public regarding potential fire danger. Aims In this paper, we introduce the Australian Fire Danger Rating System (AFDRS), providing a short historical account of fire danger rating in Australia as well as the requirements for an improved forecast system. Methods The AFDRS combines nationally consistent, spatially explicit fuel information with forecast weather and advanced fire behaviour models and knowledge to produce locally relevant ratings of fire behaviour potential. Key results A well-defined framework is essential for categorising and defining fire danger based on operational response, the potential for impact and observable characteristics of fire incidents. The AFDRS is modular, supporting continuous and incremental improvements and allowing upgrades to components in response to new science. Conclusions The AFDRS provides a new method to estimate fire danger based on the best available fire behaviour models, leading to potentially significant improvements in the way fire danger is calculated, forecast and interpreted. Implications The Australian Fire Danger Rating System was implemented in 2022, the most significant change to fire danger forecasting in Australia in more than 50 years.
Equity and modeling in sustainability science: Examples and opportunities throughout the process
Authors: Giang Amanda , Edwards Morgan R. , Fletcher Sarah M. , Gardner-Frolick Rivkah , Gryba Rowenna , Mathias Jean-Denis , Venier-Cambron Camille , Anderies John M. , Berglund Emily , Carley Sanya , Erickson Jacob Shimkus , Grubert Emily , Hadjimichael Antonia , Hill Jason , Mayfield Erin , Nock Destenie , Pikok Kimberly Kivvaq , Saari Rebecca K. , Samudio Lezcano Mateo , Siddiqi Afreen , Skerker Jennifer B. , Tessum Christopher W.
Published: March 2024

Equity is core to sustainability, but current interventions to enhance sustainability often fall short in adequately addressing this linkage. Models are important tools for informing action, and their development and use present opportunities to center equity in process and outcomes. This Perspective highlights progress in integrating equity into systems modeling in sustainability science, as well as key challenges, tensions, and future directions. We present a conceptual framework for equity in systems modeling, focused on its distributional, procedural, and recognitional dimensions. We discuss examples of how modelers engage with these different dimensions throughout the modeling process and from across a range of modeling approaches and topics, including water resources, energy systems, air quality, and conservation. Synthesizing across these examples, we identify significant advances in enhancing procedural and recognitional equity by reframing models as tools to explore pluralism in worldviews and knowledge systems; enabling models to better represent distributional inequity through new computational techniques and data sources; investigating the dynamics that can drive inequities by linking different modeling approaches; and developing more nuanced metrics for assessing equity outcomes. We also identify important future directions, such as an increased focus on using models to identify pathways to transform underlying conditions that lead to inequities and move toward desired futures. By looking at examples across the diverse fields within sustainability science, we argue that there are valuable opportunities for mutual learning on how to use models more effectively as tools to support sustainable and equitable futures.
Uncommon and nonpartisan: Antidemocratic attitudes in the American public
Authors: Holliday Derek E. , Iyengar Shanto , Lelkes Yphtach , Westwood Sean J.
Published: March 2024

Democratic regimes flourish only when there is broad acceptance of an extensive set of norms and values. In the United States, fundamental democratic norms have recently come under threat from prominent Republican officials. We investigate whether this antidemocratic posture has spread from the elite level to rank-and-file partisans. Exploiting data from a massive repeated cross-sectional and panel survey (

n

= 45,095 and 5,231 respectively), we find that overwhelming majorities of the public oppose violations of democratic norms, and virtually nobody supports partisan violence. This bipartisan consensus remains unchanged over time despite high levels of affective polarization and exposure to divisive elite rhetoric during the 2022 political campaign. Additionally, we find no evidence that elected officials’ practice of election denialism encourages their constituents to express antidemocratic attitudes. Overall, these results suggest that the clear and present threat to American democracy comes from unilateral actions by political elites that stand in contrast to the views of their constituents. In closing, we consider the implications of the stark disconnect between the behavior of Republican elites and the attitudes of Republican voters.
ERK signaling expands mammalian cortical radial glial cells and extends the neurogenic period
Authors: Sun Mengge , Gao Yanjing , Li Zhenmeiyu , Yang Lin , Liu Guoping , Xu Zhejun , Guo Rongliang , You Yan , Yang Zhengang
Published: March 2024

The molecular basis for cortical expansion during evolution remains largely unknown. Here, we report that fibroblast growth factor (FGF)-extracellular signal-regulated kinase (ERK) signaling promotes the self-renewal and expansion of cortical radial glial (RG) cells. Furthermore, FGF-ERK signaling induces
bone morphogenic protein 7
(
Bmp7
) expression in cortical RG cells, which increases the length of the neurogenic period. We demonstrate that ERK signaling and Sonic Hedgehog (SHH) signaling mutually inhibit each other in cortical RG cells. We provide evidence that ERK signaling is elevated in cortical RG cells during development and evolution. We propose that the expansion of the mammalian cortex, notably in human, is driven by the ERK-BMP7-GLI3R signaling pathway in cortical RG cells, which participates in a positive feedback loop through antagonizing SHH signaling. We also propose that the relatively short cortical neurogenic period in mice is partly due to mouse cortical RG cells receiving higher SHH signaling that antagonizes ERK signaling.
Cip1, a CDK regulator, determines heterothallic mating or homothallic selfing in a protist
Authors: Ma Yang , Yan Guanxiong , Zhang Jing , Xiong Jie , Miao Wei
Published: March 2024

Mating type (sex) plays a crucial role in regulating sexual reproduction in most extant eukaryotes. One of the functions of mating types is ensuring self-incompatibility to some extent, thereby promoting genetic diversity. However, heterothallic mating is not always the best mating strategy. For example, in low-density populations or specific environments, such as parasitic ones, species may need to increase the ratio of potential mating partners. Consequently, many species allow homothallic selfing (i.e., self-fertility or intraclonal mating). Throughout the extensive evolutionary history of species, changes in environmental conditions have influenced mating strategies back and forth. However, the mechanisms through which mating-type recognition regulates sexual reproduction and the dynamics of mating strategy throughout evolution remain poorly understood. In this study, we show that the Cip1 protein is responsible for coupling sexual reproduction initiation to mating-type recognition in the protozoal eukaryote
Tetrahymena thermophila
. Deletion of the Cip1 protein leads to the loss of the selfing-avoidance function of mating-type recognition, resulting in selfing without mating-type recognition. Further experiments revealed that Cip1 is a regulatory subunit of the Cdk19–Cyc9 complex, which controls the initiation of sexual reproduction. These results reveal a mechanism that regulates the choice between mating and selfing. This mechanism also contributes to the debate about the ancestral state of sexual reproduction.
The phospholipids cardiolipin and phosphatidylethanolamine differentially regulate MDC biogenesis
Authors: Xiao Tianyao , English Alyssa M. , Wilson Zachary N. , Maschek J.Alan. , Cox James E. , Hughes Adam L.
Published: March 2024

Cells utilize multiple mechanisms to maintain mitochondrial homeostasis. We recently characterized a pathway that remodels mitochondria in response to metabolic alterations and protein overload stress. This remodeling occurs via the formation of large membranous structures from the mitochondrial outer membrane called mitochondrial-derived compartments (MDCs), which are eventually released from mitochondria and degraded. Here, we conducted a microscopy-based screen in budding yeast to identify factors that regulate MDC formation. We found that two phospholipids, cardiolipin (CL) and phosphatidylethanolamine (PE), differentially regulate MDC biogenesis. CL depletion impairs MDC biogenesis, whereas blocking mitochondrial PE production leads to constitutive MDC formation. Additionally, in response to metabolic MDC activators, cellular and mitochondrial PE declines, and overexpressing mitochondrial PE synthesis enzymes suppress MDC biogenesis. Altogether, our data indicate a requirement for CL in MDC biogenesis and suggest that PE depletion may stimulate MDC formation downstream of MDC-inducing metabolic stress.
Competitive fungal commensalism mitigates candidiasis pathology
Authors: Sekeresova Kralova Jarmila , Donic Catalina , Dassa Bareket , Livyatan Ilana , Jansen Paul Mathias , Ben-Dor Shifra , Fidel Lena , Trzebanski Sébastien , Narunsky-Haziza Lian , Asraf Omer , Brenner Ori , Dafni Hagit , Jona Ghil , Boura-Halfon Sigalit , Stettner Noa , Segal Eran , Brunke Sascha , Pilpel Yitzhak , Straussman Ravid , Zeevi David , Bacher Petra , Hube Bernhard , Shlezinger Neta , Jung Steffen
Published: March 2024

The mycobiota are a critical part of the gut microbiome, but host–fungal interactions and specific functional contributions of commensal fungi to host fitness remain incompletely understood. Here, we report the identification of a new fungal commensal, Kazachstania heterogenica var. weizmannii, isolated from murine intestines. K. weizmannii exposure prevented Candida albicans colonization and significantly reduced the commensal C. albicans burden in colonized animals. Following immunosuppression of C. albicans colonized mice, competitive fungal commensalism thereby mitigated fatal candidiasis. Metagenome analysis revealed K. heterogenica or K. weizmannii presence among human commensals. Our results reveal competitive fungal commensalism within the intestinal microbiota, independent of bacteria and immune responses, that could bear potential therapeutic value for the management of C. albicans–mediated diseases.
One in, one out: Commensal fungus protects against infection
Authors: Drummond Rebecca A.
Published: March 2024

Gut-resident fungi have a broad influence over health and disease. In this issue of JEM, Sekeresova Kralova et al. (https://doi.org/10.1084/jem.20231686) identify a commensal yeast that displaced fungal pathogen Candida albicans and protected against subsequent invasive infections that originate from the gut.
Pulsed voltage cold atmospheric plasma jet and gold nanoparticles enhance cytotoxic anticancer effect
Authors: Schweigert I , Biryukov M , Polyakova A , Krychkova N , Gorbunova E , Epanchintseva A , Pyshnaya I , Zakrevsky Dm , Milakhina E , Koval O
Published: March 2024

Efficient and biologically safe mode of cold atmospheric plasma jet (CAPJ) is crucial for the development of CAPJ-based anticancer therapy. In the experiment and numerical simulations, by changing the pulse duration of a positive-pulsed (PP) voltage, we found the optimal CAPJ modes with a regular streamer propagation and a maximum discharge current at a temperature

T
<

42 ∘C. These CAPJs substantially suppressed the viability of cancer cells. To enhance a cytotoxic effect of CAPJ treatment, gold nanoparticles (NPs) were added to the cells before and after the CAPJ exposure. Combination of CAPJ, generated with the PP voltage, and gold NPs decreased the viability of NCI-H23 epithelial-like lung adenocarcinoma, A549 lung adenocarcinoma, BrCCh4e-134 breast adenocarcinoma and uMel1 uveal melanoma cells. Polyethylene glycol-modified NPs with attached fluorescent labels were used to visualize the uptake of NPs. We demonstrated that NPs efficiently entered the cells when were added to the cells just before CAPJ exposure or up to two hours afterwards. The efficiency of NPs penetration into cells positively correlated with the induced cytotoxic effect: it was maximal when NPs was added to cells right before or immediately after CAPJ exposure. Summarizing, the treatment with optimal CAPJ modes in combination with modified NPs, bearing the cancer-addressed molecules and therapeutics may be the next strategy of strengthening the CAPJ-based antitumor approaches.
Signatures of quantum phases in a dissipative system
Authors: Joshi Rohan , Mondal Saikat , Bandyopadhyay Souvik , Bhattacharjee Sourav , Agarwala Adhip
Published: March 2024

Lindbladian formalism, as tuned to dissipative and open systems, has been all-pervasive to interpret non-equilibrium steady states of quantum many-body systems. We study the fate of free fermionic and superconducting phases in a dissipative one-dimensional Kitaev model—where the bath acts both as a source and a sink of fermionic particles with different coupling rates. As a function of these two couplings, we investigate the steady state, its entanglement content, and its approach from varying initial states. Interestingly, we find that the steady state phase diagram retains decipherable signatures of ground state critical physics. We also show that early-time fidelity is a useful marker to find a subclass of phase transitions in such situations. Moreover, we show that the survival of critical signatures at late-times, strongly depend on the thermal nature of the steady state. This connection hints at a correspondence between quantum observables and classical magnetism in the steady state of such systems. Our work uncovers interesting connections between dissipative quantum many-body systems, thermalization of a classical spin and many-body quantum critical phenomena.
A polynomial model with line-of-sight constraints for Lagrangian particle tracking under interface refraction
Authors: Zeng Xin , Qu Hao , He Chuangxin , Liu Yingzheng , Gan Lian
Published: March 2024

This paper introduces an improvement of the ‘shake-the-box (STB)’ (Schanz, Gesemann, and Schröder, Exp. Fluids 57.5, 2016) technique using the polynomial calibration model and the line-of-sight constraints (LOSC) to overcome the refractive interface issues in Lagrangian particle tracking (LPT) measurement. The method (named LOSC-LPT) draws inspiration from the two-plane polynomial camera calibration in tomographic particle image velocimetry (Worth, Nickels, Thesis, 2010) and the STB-based open-source Lagrangian particle tracking (OpenLPT) framework (Tan, Salibindla, Masuk, and Ni, Exp. Fluids 61.2, 2019). The LOSC-LPT introduces polynomial mapping functions into STB calibration in conditions involving gas–solid–liquid interfaces at container walls exhibiting large refractive index variations, which facilitates the realization of particle stereo matching, three-dimensional (3D) triangulation, iterative particle reconstruction, and further refinement of 3D particle position by shaking the LOS. Performance evaluation based on synthetic noise-free images with a particle image density of 0.05 particle per pixel in the presence of refractive interfaces demonstrates that LOSC-LPT can detect a higher number of particles and exhibits lower position uncertainty in the reconstructed particles, resulting in higher accuracy and robustness than that achieved with OpenLPT. In the application to an elliptical jet flow in an octagonal tank with refractive interfaces, the use of polynomial mapping results in smaller errors (mean calibration error <0.1 px) and thus more long trajectories identified by LOSC-LPT (13 000) compared with OpenLPT (4500) which uses the pinhole Tsai model (mean calibration error >1.0 px). Moreover, 3D flow-field reconstructions demonstrate that the LOSC-LPT framework can recover a more accurate 3D Eulerian flow field and capture more complete coherent structures in the flow, and thus holds great potential for widespread application in 3D experimental fluid measurements.
A digital twin library of mechanical transmission system for the application of small sample fault diagnosis problem
Authors: Meng Xianglong , Hu Tianliang , Li Jinfeng , Zhang Yan , Ma Songhua
Published: March 2024

Timely and accurate fault diagnosis of transmission systems is crucial to ensuring the systems’ reliability, safety, and economic viability. However, intelligent fault diagnosis algorithms require a lot of labeled data for training, which may not be available and accessible, especially for many critical devices. This hinders the application of some excellent diagnosis methods in real industry. Digital twin (DT), as an advanced cyber-physical integration method, can be utilized to generate rich fidelity data with virtual models to overcome the dilemma of insufficient data, especially for the small sample problem. We propose the DT library to model the mechanical transmission system with various faults for the data augmentation of the small sample problem. In the library, common components in mechanical transmission systems are modular and digitalized into several differential equations. They can compose a mechanical transmission system digital twin (TSDT) and be injected with various faults to simulate the transmission signal, and even replace the physical experimental platform. The simulation data is used as a pre-training dataset, which can be imported into the transfer learning method for the fault diagnosis. After several verifications, it can be concluded that the simulation data from TSDT is effective in transfer ability and fault feature learning, which significantly improves fault recognition accuracy in the small sample problem.
Multilayer modeling framework for analyzing thermo-mechanical properties and responses of twisted and coiled polymer actuators
Authors: Gao Zhiwen , Guo Juanjuan , Zhang Yuhao , Zhou Zhiwen , Zhang Cennan , Li Hua , Chen Bin , Wang Jizeng
Published: March 2024

The twisted and coiled polymer actuator (TCPA) has a complex multi-scale structure consisting of crystalline micro-fibrils and an amorphous matrix at the micro-scale, which are organized into a macro-scale fiber. When the polymer fiber undergoes twisting and coiling, its mechanical and thermal properties become variable. In this study, we developed a multi-layer modeling framework capable of accurately predicting the effective mechanical and thermal properties, as well as the thermo-mechanical responses of the TCPA. Our numerical results demonstrate that the effective mechanical and thermal properties of the TCPA are influenced by the radius and twisting angle of the polymer fiber. By analyzing the precise mechanical and thermal properties, the numerical calculated driving responses exhibit good agreement with experimental data. We also examined the influence of initial helical radius, helical pitch and fiber radius on the driving responses of the TCPA. The proposed numerical model can be further utilized to optimize the driving responses of the TCPA by adjusting geometric parameters and the twisting angle of the polymer fiber.
FEA and CFD analysis and optimization of tube in tube heat exchanger for various cases
Authors: Shah Abhijeet , Wasnik Ankit , Patil Ajinkya
Published: March 2024

This research describes the use of advanced simulation techniques to investigate use of different materials for a tube-in-tube heat exchanger. Finite Element Analysis (FEA) and Computational Fluid Dynamics (CFD) simulations are employed to simulate thermal aspects and optimize the heat exchanger design. The objective is to identify the best-Suitable material combination considering both design and thermal considerations. The findings of this research contribute to the development of more efficient heat exchanger designs.
Leveraging the strain transfer at the interface between self-composite CoFe2O4 embedded in pre-sintered Na0.5Bi0.5TiO3 ceramics matrix for the enhancement of magnetoelectric voltage coefficient
Authors: Dharsini P M Priya , Priya Bhadra , Nandakumar K , Sundarakannan B
Published: March 2024

Magnetoelectric particulate composite (100-x) NBT- xCFO(sc) (x = 5,15,25,35) were prepared from pre-sintered NBT and self-composite CFO(sc) by solid-state reaction route. XRD, SEM, and Raman studies confirm the biphasic composite formation without diffusion at the interfaces. Unsaturated ferroelectric loops and enhanced ferromagnetic properties are evidenced. ME coefficient value is enhanced to 25.1 mV cm−1 Oe in the N65SC35 composite which is the greatest among the reported values in the literature of NBT-CFO composites. The enhancement is due to the effective strain transfer at the interfaces of the composites. This is explained by a simple dimensionless quantity, degree of interface. This quantity is defined using the interface length of ferroelectric-ferromagnetic phases and the weighted average grain size which corroborates the enhancement of the ME coefficient.
Numerical study on spark characteristics and evolution of plasma jet igniter
Authors: Kong Defu , Ye Taohon , Xia Weidon , Chen Xianhui , Liu Baolin
Published: March 2024

In this paper, a compressible spark plasma simulation model with fully coupled electromagnetic, flow, and thermal multi-physics process is developed based on COMSOL, and the evolution of spark properties during the spark plasma development of embedded plasma jet igniter is investigated by combining high-speed ICCD experimental data. The results show that in the early stage of spark plasma discharge, strong electric field distortion occurs in the near cathode electrode area, current density and temperature rise sharply, which develop close to each other and subsequently form spark plasma discharge channels; during the discharge development period, under the continuous Joule heat deposition, the plasma channel temperature rises and volume expands, and the plasma high pressure channel formed has obvious ‘shockwave-like’ pressure interrupted surface with the surrounding environment, and the ‘shockwave-like’ pressure interrupted surface propagates and reflects in the igniter cavity, driving the plasma cluster to move outward. The energy is gradually dissipated as the spark cluster rolls outside the igniter cavity sucking in the surrounding cold air. The energy loss of the spark plasma comes mainly from the heat exchange with the surrounding environment and the partial stay in the igniter cavity of the ignition plasma cluster that fails to participate in the ignition.
Hybrid Si-Au plasmonic sensor on the end-facet of a dual-core optical fiber enhanced by hotspots: a theoretical study
Authors: Mahani Fatemeh Fouladi , Mokhtari Arash , Berini Pierre
Published: March 2024

We propose an efficient hybrid Si-Au sensor on the end-facet of a dual-core single-mode optical fiber. The design incorporates slanted Si grating couplers on the two cores, interconnected by a plasmonic waveguide bearing subwavelength corrugations. The corrugations enhance the surface sensitivity by creating regions of strongly enhanced fields - plasmonic hotspots. Unlike conventional Si waveguide grating couplers, we employ slanted slits for unidirectional coupling/decoupling between TM-polarized core light and surface plasmon polaritons. Our structure results in about 3% core-to-core (TM-to-TM) coupling efficiency, while also providing high bulk and surface sensitivities of about 1000 nm RIU−1 and 1.66 nm nm−1, respectively. The sensor can be interrogated remotely in a transmission arrangement. The sensing medium can be probed by dipping the fiber tip directly therein. Potential applications include remote sensing, brain studies, or in-vivo biosensing.
Semi-analytical modeling of electro-strictive behavior in dielectric elastomer tube actuators
Authors: Askari-Sedeh Mahdi , Baghani Mostafa
Published: March 2024

Dielectric elastomer tube actuators (DETAs) facilitate versatile soft robotic motions when activated by electric fields. However, optimizing their performance necessitates understanding complex deformation behaviors under different electrical loading patterns. While prior analytical models provide valuable insights, many rely on assumptions like infinite-length and uniform conditions, limiting their ability to capture experimentally-observed nonuniform deformations. This paper presents a semi-analytical approach permitting both radial and longitudinal electrostatic effects by modeling a dielectric tube of effectively infinite-length. It also incorporates the crucial compression-torsion behavior for soft actuator designs. We validate the model against finite element simulations, achieving excellent agreement. Our efficient technique successfully predicts intricate deformation phenomena in DETAs under combined electrical, mechanical, and geometric effects. Results show the model effectively captures axial and twisting deformations, overcoming limitations of linear twist angle assumptions. This analytical framework offers a powerful tool for optimizing next-generation soft actuators across diverse cutting-edge engineering and robotic applications.
Label-free biosensor on chip (BoC) based on localized surface plasmon resonance for monitoring temperature and blood hemoglobin concentration
Authors: Mondal Sujoy , Mohsin Abu S M , Bhuian Mohammed Belal Hossain , Mosaddequr Rahman Md , Rahad Rummanur
Published: March 2024

On-chip localized surface plasmon resonance (LSPR) biosensor on chip (BoC) is a type of label-free biosensor that utilizes the plasmonic resonances of metal nanostructures to detect changes in the refractive index of the local environment. This results in changes in the intensity and wavelength of the surface plasmon resonance, which can be used to quantify the presence and concentration of biomolecules such as proteins, nucleic acids, and cells. In this paper, we propose a novel on-chip device with a microfluidic channel that contains the biological fluid under test. We have obtained sharp resonance peaks in the wavelength range between 700–800 nm with a sensitivity of 509 nm R−1IU−1 which is good compared to other on-chip devices. The main advantage of our design is the less complex manufacturing process compared to other BoCs. Our design consists of a central cavity that is surrounded by silver and consists of rectangular pillar-shaped silver particles placed in the cavity. Two very promising applications of this device are label-free temperature sensing and blood hemoglobin (Hb) concentration sensing with a resolution of 0.222 nm/°C for temperature and 1. 34 nm/(g/dL) for Hb. However, it can be used for any kind of sensing application that involves refractive index changes as the sensing platform.
Investigating the performance of perovskite solar cell with tin oxide as electron transport layer by SCAPS-1D device simulation
Authors: Nair R Sharuvindan , Pakhuruddin Mohd Zamir
Published: March 2024

Electron transport layer (ETL) is one of the most essential layers in determining photovoltaic (PV) performance of perovskite solar cells (PSCs). The role of the ETL is to facilitate the charge collection in the device. Studies have shown that the use of tin oxide (SnO2) as ETL could improve the efficiency and stability of PSCs while reducing their degradation. In this work, the Solar Cell Capacitance Simulator (SCAPS-1D) is utilized to investigate the performance of PSCs with SnO2 as the ETL. The device is composed of FTO (Contact)/SnO2 (ETL)/CH3NH3PbI3 (Perovskite)/Cu2O (HTL)/Au (Contact). The effects of thickness, dopant concentration, and defect density of the SnO2 ETL on the performance of PSCs have been investigated. From the results, the optimum parameters for the SnO2 ETL have been identified at thickness of 10 nm, dopant concentration of 1 ×1017 cm−3 and defect density of 1 ×1014 cm−3. With the optimized parameters, the final performance of the PSC demonstrates power conversion efficiency (PCE) of 18.31%.
Non-differentiable kernel-based approximation of memory-dependent derivative for drug delivery applications
Authors: Khalaf M , Elsaid A , Hammad S F , Zahra W K
Published: March 2024

Although memory-dependent derivative (MDD) has recently been the subject of extensive study, only one numerical approximation has been reported in the literature. Hence, this study introduces a novel approximation for MDD. Moreover, a new form of the kernel function is presented. The convergence order of our approximation is

O

h

3
−
S

,
0
<
S
<
1

, where

(
1
−
S
)

is the exponent of the kernel function. The proposed approach is used to numerically solve the memory-dependent advection-diffusion problem, and the numerical scheme's stability and convergence are discussed. Also, memory-based models have been described to study drug delivery and its diffusion from multi-layer capsules/tablets. These models are based on the fractional derivative and the MDD to solve the paradox of the unphysical feature of the infinite propagation speed of the published Fickian-based models. The theoretical analysis is validated with numerical examples by investigating the convergence order that is

3
−
S

in time. To illustrate the validity and efficiency of the proposed models, profiles of concentration and drug mass are compared with the observed in vivo data. It is observed to be highly accurate and compatible with the in vivo data when compared with Fick's model.
Testing the one-way steering with any bipartite entangled state: a numerical simulation with electrons on liquid Helium
Authors: Li Yu-Fen , Feng Xia-Ning , He Sui-Rong , Wei L F
Published: March 2024

Quantum entanglement is one of the basic features of the quantum system, and it can be divided into three kinds: non-steering, one-way steering, and multi-way steering. The multi-way steering is mutual for the bipartite system, i.e., Alice can steer Bob and Bob can also steer Alice. While one-way steering is asymmetrical, it provides various potential applications for quantum information processing. The existence of one-way steering has been experimentally tested with certain specific bipartite entangled states, typically such as the optical Werner states. Here we show that any bipartite entangled state can be experimentally determined to be one-way steering or not by testing the relevant linear steering inequality. By constructing the proper unitary operations, we show that the required joint projective measurement can be performed for the tests. Specifically, we demonstrate the experimental feasibility of the proposal with a typical solid-state experimental platform, i.e., electrons trapped on liquid Helium, by applying the electron trap and microwave driving techniques.
Experimental investigation on cross-beam energy transfer between P-polarized lasers at 45-deg incidence
Authors: Kang Ning , Lei Anle , Xu Guoxiao , Liu Huiya , Zhou Shenlei , Xie Zhiyong , An Honghai , Zhou Xichen , Fang Zhiheng , Wang Wei
Published: March 2024

In this paper, we report the first experimental results on cross-beam energy transfer (CBET) at the Shengguang-II laser facility, in which two p-polarized laser beams irradiated planar targets at 45-deg incidence orthogonally. Frequency shifts of 0 and 0.06% were added between the two beams to investigate the relation of CBET to the degree of frequency shift. Enhancement of scattering was observed in the two-beam configuration with respect to the sum of the two single-beam configurations, indicating CBET was developed by the interaction of the two beams in the cases both with and without the frequency shift. When time delays were added between the seed and the pump pulses, scatter from the seed was enhanced, which further confirmed the existence of CBET in the experiments. The amplifications of the seed light by CBET with and without the frequency shift were sequentially ∼3.3 and ∼2.0 when the two beams were synchronized, and the energy loss due to CBET within the full aperture of the final optics of the pump to the total laser energy was ∼4% with the frequency shift. Calculations suggest that a more than 0.2% frequency shift may be needed to mitigate CBET under experimental laser-plasma conditions.
Thermal management by manipulating electromagnetic parameters
Authors: Wang 王 Yun 云 , Liang 梁 Di-Fei 迪飞 , Han 韩 Tian-Cheng 天成 , Deng 邓 Long-Jiang 龙江
Published: March 2024

Electromagnetic absorbing materials may convert electromagnetic energy into heat energy and dissipate it. However, in a high-power electromagnetic radiation environment, the temperature of the absorbing material rises significantly and even burns. It becomes critical to ensure electromagnetic absorption performance while minimizing temperature rise. Here, we systematically study the coupling mechanism between the electromagnetic field and the temperature field when the absorbing material is irradiated by electromagnetic waves. We find out the influence of the constitutive parameters of the absorbing materials (including uniform and non-uniform) on the temperature distribution. Finally, through a smart design, we achieve better absorption and lower temperature simultaneously. The accuracy of the model is affirmed as simulation results aligned with theoretical analysis. This work provides a new avenue to control the temperature distribution of absorbing materials.
Shape-influenced non-reciprocal transport of magnetic skyrmions in nanoscale channel
Authors: Chen 陈 Jie-Yao 杰尧 , Luo 罗 Jia 佳 , Hu 胡 Geng-Xin 更新 , Wang 王 Jun-Lin 君林 , Li 李 Guan-Qi 冠祺 , Chen 陈 Zhen-Dong 振东 , Lu 陆 Xian-Yang 显扬 , Zhao 赵 Guo-Ping 国平 , Liu 刘 Yuan 远 , Wu 吴 Jing 竞 , Xu 徐 Yong-Bing 永兵
Published: March 2024

Skyrmions, with their vortex-like structures and inherent topological protection, play a pivotal role in developing innovative low-power memory and logic devices. The efficient generation and control of skyrmions in geometrically confined systems are crucial for the development of skyrmion-based spintronic devices. In this study, we focus on investigating the non-reciprocal transport behavior of skyrmions and their interactions with boundaries of various shapes. The shape of the notch structure in the nanotrack significantly affects the dynamic behavior of magnetic skyrmions. Through micromagnetic simulation, the non-reciprocal transport properties of skyrmions in nanowires with different notch structures are investigated in this work.
FPGA and computer-vision-based atom tracking technology for scanning probe microscopy
Authors: Yu 俞 Feng-Du 风度 , Liu 刘 Li 利 , Wang 王 Su-Ke 肃珂 , Zhang 张 Xin-Biao 新彪 , Lei 雷 Le 乐 , Huang 黄 Yuan-Zhi 远志 , Ma 马 Rui-Song 瑞松 , Huan 郇 Qing 庆
Published: March 2024

Atom tracking technology enhanced with innovative algorithms has been implemented in this study, utilizing a comprehensive suite of controllers and software independently developed domestically. Leveraging an on-board field-programmable gate array (FPGA) with a core frequency of 100 MHz, our system facilitates reading and writing operations across 16 channels, performing discrete incremental proportional-integral-derivative (PID) calculations within 3.4 microseconds. Building upon this foundation, gradient and extremum algorithms are further integrated, incorporating circular and spiral scanning modes with a horizontal movement accuracy of 0.38 pm. This integration enhances the real-time performance and significantly increases the accuracy of atom tracking. Atom tracking achieves an equivalent precision of at least 142 pm on a highly oriented pyrolytic graphite (HOPG) surface under room temperature atmospheric conditions. Through applying computer vision and image processing algorithms, atom tracking can be used when scanning a large area. The techniques primarily consist of two algorithms: the region of interest (ROI)-based feature matching algorithm, which achieves 97.92% accuracy, and the feature description-based matching algorithm, with an impressive 99.99% accuracy. Both implementation approaches have been tested for scanner drift measurements, and these technologies are scalable and applicable in various domains of scanning probe microscopy with broad application prospects in the field of nanoengineering.
ρ-meson longitudinal leading-twist distribution amplitude revisited and the D→ρ semileptonic decay*
Authors: Zhong 钟 Tao 涛 , Dai 代 Ya-Hong 亚红 , Fu 付 Hai-Bing 海冰
Published: March 2024

Motivated by our previous study [Phys. Rev. D 104(1), 016021 (2021)] on the pionic leading-twist distribution amplitude (DA), we revisit the ρ-meson leading-twist longitudinal DA

in this study. A model proposed by Chang based on the Dyson-Schwinger equations is adopted to describe the behavior of

. However, the ξ-moments of

are calculated with the QCD sum rules in the framework of the background field theory. The sum rule formulas for these moments are improved. More accurate values for the first five nonzero ξ-moments at the typical scale

are given, e.g., at

,

,

,

,

, and

. By fitting these values with the least squares method, the DSE model for

is determined. By taking the left-handed current light-cone sum rule approach, we obtain the transition form factor in the large recoil region, i.e.,

,

, and

, and the ratio

,

. After extrapolating with a rapidly converging series based on

-expansion, we present the

-independent decay width for the semileptonic decays

. Finally, the branching fractions are

,

,

, and

.
Preliminary analyses of the dynamics and thermodynamics of rotating regular black holes*
Authors: Yang 杨 Hao 昊 , Yu 余 Chang-Jiang 长江 , Miao 缪 Yan-Gang 炎刚
Published: March 2024

We investigate the dynamic and thermodynamic laws governing rotating regular black holes. By analyzing dynamic properties, i.e., the interaction between scalar particles and rotating regular black holes, we establish the criteria that determine whether such black holes satisfy the laws of thermodynamics. In addition, we provide the general form of conserved quantities related to rotating regular black holes, including the relevant flows associated with neutral scalar particles. Meanwhile, we reexamine the relationship between the third law of thermodynamics and weak cosmic censorship conjecture for rotating regular black holes. Based on the abovementioned criteria, we discuss the laws of thermodynamics for three models of rotating regular black holes: Rotating Hayward black holes, Kerr black-bounce solutions, and loop quantum gravity black holes. Our findings indicate that none of the three models satisfies the first law of thermodynamics. In particular, the first and third models fail to comply with the three laws of thermodynamics, whereas the second model satisfies only the second and third laws of thermodynamics. Finally, we attempt to rescue the laws of thermodynamics by modifying entropy or extending the phase space. However, the two scenarios cannot ensure the three laws of thermodynamics in the three models, which reveals an unusual property of rotating regular black holes.
Impacts of gravitational-wave background from supermassive black hole binaries on the detection of compact binaries by LISA*
Authors: Huang 黄 Fan 帆 , Bi 毕 Yan-Chen 研晨 , Cao 曹 Zhoujian 周键 , Huang 黄 Qing-Guo 庆国
Published: March 2024

In the frequency band of the Laser Interferometer Space Antenna (LISA), extensive research has been conducted on the impact of foreground confusion noise generated by galactic binaries within the Milky Way Galaxy. Additionally, recent evidence of a stochastic signal, announced by the NANOGrav, EPTA, PPTA, CPTA, and InPTA, indicates that the stochastic gravitational-wave background (SGWB) generated by supermassive black hole binaries (SMBHBs) can contribute strong background noise within the LISA band. Given the presence of such strong noise, it is expected to have significant impacts on LISA's scientific missions. In this study, we investigate the impacts of the SGWB generated by SMBHBs on the detection of individual massive black hole binaries, verified galactic binaries, and extreme mass ratio inspirals in the context of LISA. We find it essential to resolve and eliminate the excess noise from the SGWB to guarantee the success of LISA's missions.