bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phase-restoring subpixel image registration: enhancing motion detection performance in Fourier-domain optical coherence tomography
Authors: Li Huakun , Tan Bingyao , Pandiyan Vimal Prabhu , Barathi Veluchamy Amutha , Sabesan Ramkumar , Schmetterer Leopold , Ling Tong 
Published: February 2025

Abstract
Phase-sensitive Fourier-domain optical coherence tomography (FD-OCT) enables in-vivo, label-free imaging of cellular movements with detection sensitivity down to the nanometer scale, and it is widely employed in emerging functional imaging modalities, such as optoretinography (ORG), Doppler OCT, and optical coherence elastography. However, when imaging tissue dynamics in vivo, inter-frame displacement introduces decorrelation noise that compromises motion detection performance, particularly in terms of sensitivity and accuracy. Here, we demonstrate that the displacement-related decorrelation noise in FD-OCT can be accurately corrected by restoring the initial sampling points using our proposed Phase-Restoring Subpixel Image Registration (PRESIR) method. Derived from a general FD-OCT model, the PRESIR method enables translational shifting of complex-valued OCT images over arbitrary displacements with subpixel precision, while accurately restoring phase components. Unlike conventional approaches that shift OCT images either in the spatial domain at the pixel level or in the spatial frequency domain for subpixel correction, our method reconstructs OCT images by correcting axial displacement in the spectral domain (k domain) and lateral displacement in the spatial frequency domain. We validated the PRESIR method through simulations, phantom experiments, and in-vivo ORG in both rodents and human subjects. Our approach significantly reduced decorrelation noise during the imaging of moving samples, achieving phase sensitivity close to the fundamental limit determined by the signal-to-noise ratio.
Thermoelectric properties of marcasite-type compounds MSb2 (M = Ta, Nb): a combined experimental and computational study
Authors: Sk Shamim , Sato Naoki , Mori Takao 
Published: February 2025

Abstract
Here, we investigate the thermoelectric properties of the marcasite-type compounds MSb2 (M = Ta, Nb) in the temperature range of 310–730 K. These compounds were synthesized by a solid-state reaction followed by the spark plasma sintering process. The Rietveld refinement method confirms the monoclinic phase with space group C2/m for both compounds. The observed values of Seebeck coefficients exhibit non-monotonic behaviour in the studied temperature range, with the maximum magnitude of −14.4 and −22.7 µV K−1 for TaSb2 and NbSb2, respectively at ∼444 K. The negative sign of S in the full temperature window signifies the n-type behaviour of these compounds. Both electrical and thermal conductivities show decreasing trends with increasing temperature. The experimentally observed thermoelectric properties are understood through the first-principles DFT and Boltzmann transport equation. A pseudogap in the density of states around the Fermi level characterizes the semimetallic behaviour of these compounds. The multi-band electron and hole pockets were found to be mainly responsible for the temperature dependence of transport properties. The experimental power factors are found to be ∼0.09 and ∼0.42 mW m−1 K−2 at 300 K for TaSb2 and NbSb2, respectively. We found that there is much room for improvement of power factor by tuning carrier concentration. The DFT-based calculations predict the maximum possible power factors at fairly high doping concentrations. The present study suggests that the combined DFT and Boltzmann transport theory are found to be reasonably good at explaining the experimental transport properties, and moderate power factors are predicted.
A ConvLSTM-based model for predicting thermal damage during laser interstitial thermal therapy
Authors: Gao Tingting , Liang Libin , Ding Hui , Zhang Chao , Wang Xiu , Hu Wenhan , Zhang Kai , Wang Guangzhi 
Published: February 2025

Abstract

Objective. Accurate prediction of thermal damage extent is essential for effective and precise thermal therapy, especially in brain laser interstitial thermal therapy (LITT). Immediate postoperative contrast-enhanced T1-weighted imaging (CE-T1WI) is the primary method for clinically assessing in vivo thermal damage after image-guided LITT. CE-T1WI reveals a hyperintense enhancing rim surrounding the target lesion, which serves as a key radiological marker for evaluating the thermal damage extent. Although widely used in clinical practice, traditional thermal damage models rely on empirical parameters from in vitro experiments, which can lead to inaccurate predictions of thermal damage in vivo. Additionally, these models predict only two tissue states (damaged or undamaged), failing to capture three tissue states observed on post-CE-T1WI images, highlighting the need for improved thermal damage prediction methods. Approach. This study proposes a novel convolutional long short-term memory-based model that utilizes intraoperative temperature distribution history data measured by magnetic resonance temperature imaging (MRTI) during LITT to predict the enhancing rim on post-CE-T1WI images. This method was implemented and evaluated on retrospective data from 56 patients underwent brain LITT. Main results. The proposed model effectively predicts the enhancing rim on postoperative images, achieving an average dice similarity coefficient of 0.82 (

±

0.063) on the test dataset. Furthermore, it generates real-time predicted thermal damage area variation trends that closely resemble those of the traditional thermal damage model, suggesting potential for real-time prediction of thermal damage extent. Significance. This method could provide a valuable tool for visualizing and assessing intraoperative thermal damage extent.
Insights into the crystallization, topographical, and tribological properties of sustainable PEO-mica based triboelectric nanogenerators
Authors: Johnson Aliesha D , Barri Nima , Salari Meysam , Mohseni Taromsari Sara , Rastegardoost Mohammad M , Filleter Tobin , Saadatnia Zia , Naguib Hani E 
Published: February 2025

Abstract
Contact electrification is the primary mechanism dictating electron transfer and surface charge density for triboelectric nanogenerators (TENGs), making intrinsic material and physical surface properties key parameters for the interfacial charge transfer phenomena. Surface properties are governed by the morphological and textural microstructural features, including tribological interactions, topographical profiling, surface roughness, and real contact area. Therefore, understanding surface morphological effects on the triboelectric performance aids development towards adapting and optimizing surface properties. Particularly, in polymer-based composites TENGs, the surface morphology relies on polymer crystallization and interactions with reinforcing additives. This comprehensive study evaluated the effects of isothermal crystallization and the incorporation and dispersibility of raw and few-layer exfoliated muscovite mica fillers, insightfully realizing and tuning polyethylene oxide’s intrinsic properties and semi-crystalline microstructure. The full material characterization presented dramatic variations in polymer growth kinetics, chain dynamics, lamellae profiling, surface roughness, and work functions, allowing the development of a constructive triboelectric surface microstructural design guide. The crystallization temperature of 65 °C with raw mica demonstrated the greatest dielectric properties and triboelectric performance resulting in a peak-to-peak voltage, peak-to-peak current density, transferred charge density, and power density of respectively, 488 V, 45.5 mA m−2, 152 μC m−2, and 24.0 W m−2 at a load resistance of 6 MΩ. The TENG device demonstrated stable long-term voltage outputs over the duration of 12 000 contact-separation cycles and successfully self-powered natural resource environmental monitoring sensors.
Large-scale tuning of exciton binding energy and reconfiguration in van der Waals heterostructures
Authors: Chen Yingda , Lou Wenkai , Yang Wen , Chang Kai 
Published: February 2025

Abstract
We present an explicit framework for large-scale, in-situ control of exciton binding energy and ground-state reconfiguration in arbitrary multi-layer van der Waals heterostructures through screening effects induced by unbiased electrode gates. This method enables a reduction in exciton binding energy by up to an order of magnitude and facilitates zero-field reconfiguration of intralayer excitons. Furthermore, by applying a weak in-plane electric field, enhanced by the electrode screening, we achieve efficient intralayer-interlayer exciton reconfiguration. This approach significantly lowers the required critical field strength—by an order of magnitude compared to conventional out-of-plane fields—due to enhanced electron–hole dissociation. Our findings open new avenues for the flexible and efficient control of excitonic devices.
Perfect Fluid Kantowski-Sachs and Bianchi Type-III Spacetimes and Their ConcircularSymmetry in f(T) theory of gravity
Authors: Ali Ahmad Tawfik , Khan Suhail , Shah Syed Majid 
Published: February 2025

Abstract
The aim of this research is to classify Kantowski-Sachs (KS) and Bianchi type-III spacetimes through concircular vector fields in $f(T)$ gravity theory. In order to achieve our goal we first obtained field equations for KS and Bianchi type-III spacetimes with perfect fluid as source in $f(T)$ theory of gravity and then obtained the concircular symmetry equations. All these equations are solved simultaneously to obtain the vector field components. The whole process enabled us to obtain particular form of the metric functions and conformal factors. It has been found that perfect fluid KS and Bianchi type-III spacetimes allow concircular vector fields of 4-, 5-, 6-, 7- and 15-dimensions in $f(T)$ gravity theory. The torsion scalar $T$, fluid pressure and energy density are all computed in each case. It has been shown that in all cases except one case pressure and density are constants. It has been observed that pressure and density are linked as $p\,=\,-\rho$ in all the cases except two case, indicating that these spacetime metrics may represent a vacuum universe or a universe with dark energy.	In one case $p\,=\,\rho$, means that the spacetime has an ordinary matter and in other case the pressure of the fluid and density are functions of the cosmic time $t$. By choosing particular values of the constants in this case, an equation of state $p\,=\,-\rho$ can be achieved.
High gain SIW integrated reconfigurable MIMO antenna in THz regime
Authors: Kulshreshtha Mayuri , Bhattacharya Rajarshi 
Published: February 2025

Abstract
A new design of a reconfigurable multiple input multiple output (MIMO) antenna with dual-band/triple-band response is presented in this article. The graphene strips are placed above the decoupling structure near the ports to create additional resonance. Graphene changes the surface current arrangement, resulting in a reconfigurable antenna response. The proposed antenna without graphene strip resonates at resonating bands (1.66–1.81 THz), and (4.11–4.69 THz) with impedance bandwidths of 8.7%, and 13.06% respectively. The proposed antenna with graphene strip resonates at (1.62–1.77 THz), (2.55–2.70 THz), and (4.16–4.79 THz) frequencies with impedance bandwidth of 4.73%, 5.7%, and 14.12% respectively. The designed antenna offers high gain (9.6 dBi) with maximum efficiency (70%). The area of the proposed antenna is 100 × 80 μm2. The proposed structure shows excellent diversity performance including ECC, DG, TARC, and channel capacity loss across all operating bands.
Influence of spread of the Josephson junction parameters on the radiation characteristics of active Josephson antennas
Authors: Galin M A , Shereshevsky I A , Vdovicheva N K , Kurin V V 
Published: February 2025

Abstract
The influence of spread of the Josephson junction parameters on the emission spectrum and on radiation power of the active Josephson antenna has been analyzed using direct numerical simulation. Active Josephson antennas represent superwavelength open systems with a large number of Josephson junctions radiating into open space. Critical currents and normal resistances of junctions have been considered as parameters with the spreads. It has been shown that the spread of parameters does not distort a general form of spectrum consisting from a narrow monochromatic line and a wide pedestal underneath. The dependence of the power in this line on the spread of parameters at different number of junctions in the antenna has been studied. It has been shown that the radiation power generally decreases with the increase of the spread and the greater the number of junctions in the array the less the rate of this decrease.
Phosphor-converted laser-based solid-state lighting device in transmission mode using transparent conducting oxide substrate.
Authors: Soni Aayushi , mulaveesala Ravibabu , Dubey Satish Kumar , Mehta Dalip Singh 
Published: February 2025

Abstract
Laser excitation of phosphorescent material (inorganic phosphor) to produce super-bright white light leads to thermal quenching. This article presents an innovative thermal heat reduction scheme that addresses the issue of phosphor heating. This study demonstrates a transparent conducting oxide film on a glass substrate under three conditions: low laser power with a heat sink, high laser power, and increased glass thickness. The characteristics of produced white light are examined in detail, and a thermal equivalent circuit is devised. Indium-tin oxide (ITO) film mitigates thermal and color instability issues, along with the flickering of a light source in transmission mode. Owing to the elevated conductivity of ITO film, it functions as a heat sink, absorbing thermal energy from the phosphor (luminescent material). It disperses to the underlying glass substrate via diffusion and into the ambient air more effectively than a conventional glass substrate. It is more economical than utilizing diamond, gold, or sapphire substrates. This work is expected to boost the applications of transmissive laser lighting. Experimental results of laser-based solid-state lighting (LBSSL) devices in transmission mode are presented utilizing indium-tin-oxide coated glass (ITOG). We observed substantial heat conduction through ITOG and reduced thermal quenching of the photoluminescent spectrum compared to standard glass.
Temperature-controlled metasurface terahertz wave modulator based on high-temperature magnetron-sputtered strontium titanate
Authors: Zhang Yong Gang , Zhang Xing Yu , Li Zhen Hua , Liang Lan Ju , Yan Xin , Yao Hai Yun , Wang Zi Qun , Hu Xiao Fei , Shi Zhao Yang , Huai Fei , Wu Jin Tao , Wang Qing Yi , Chen Yong Zhen 
Published: February 2025

Abstract
In this study, a series of temperature-controlled terahertz (THz) wave modulators based on a combination of magnetron-sputtered strontium titanate (STO) thin films and metasurfaces have been proposed. As the sputtering temperature increased from 25 to 600°C, the STO thin films exhibited an evolution from amorphous to polycrystalline states and thus different dielectric responses were observed in the THz band. Differences in the performance of the THz wave modulators such as differences in the variation trends of the amplitude and frequency of the resonance peaks as a function of the heating temperature were observed in the THz transmission spectra. The variation in the permittivity as a function of heating also exhibited different trends for the as-deposited STO films and fabricated modulators when the sputtering temperature was increased. Although a maximum amplitude modulation depth of 29.8% was obtained for the modulator with STO sputtered at 25°C, the frequency-shift exhibited nearly no regular variation on heating. On the contrary, amplitude as well as frequency modulations were achieved for the THz wave when the sputtering temperature of STO for the modulator exceeded 200°C. This study presents a high-temperature sputtering method for fabricating STO temperature-controlled modulators that can provide simultaneous modulation of amplitude and frequency of THz waves.
Flexible regulation for broadband of flexural wave by solid-liquid reconfigurable metastructure
Authors: Nan Xulei , Li Lixia 
Published: February 2025

Abstract
Metastructures have shown good application prospects in wavefront manipulation. By studying the reconfigurable characteristics of metastructure, the great potential of metastructures in the multi-functional flexible control of flexural waves can be revealed. In this paper, a broadband flexible reconfigurable elastic solid–liquid-type metastructure is proposed. By filling cylindrical cavities with different volumes of liquid, the flexural wave band structure of the solid–liquid metastructure unit cell is regulated. Based on the functional relationship between the flexural wave frequency dispersion curve and the phase, the 0–2π accurate phase change of the flexural wave over a broadband range is realized. The design of subwavelength elastic metastructure based on the generalized Snell’s law realizes the specified angular refraction of flexural waves over a wide range of frequencies without the need to remanufacture the metastructure. In addition, based on the bandgap properties of metamaterials, a metastructure for bidirectional selective transmission of flexural waves is designed. Finally, by changing the height of the liquid surface, the multiple functions of the solid–liquid reconfigurable metastructure in beam focusing and the phenomenon of generating non-diffracting Bessel beam are demonstrated. And when focusing the beam, we find a phenomenon, which uses a fixed phase profile to achieve flexural wave focusing at different frequencies. The reconfigurable solid–liquid type metastructure proposed in this paper provide a modulation for the active regulating of elastic flexural waves within a wide range of frequency, and provides a new idea for the development of reconfigurable elastic metastructure.
Isolation enhancement and RCS reduction MIMO antenna using polarization conversion metasurface
Authors: Li Yujun , Tang Ziyue , Zhang Di , Chen Qiang , Zhu Zhenbo , Huang Min , Cheng Houyuan 
Published: February 2025

Abstract
An isolation enhancement and radar cross section (RCS) reduction multiple input multiple output (MIMO) antenna is proposed with the simple rectangular polarization conversion metasurface (PCM). The distance between the compact antenna elements is only 0.19λ. In order to enhance antenna isolation and reduce RCS, PCM unit and its image are loaded in the middle area, floor area and patch area of the antenna. The PCM not only weakens the coupling field between the ports, enhances the isolation of the antenna, but also affects the propagation of the incoming wave reflection wave and reduces the RCS of the antenna. Loading PCM to solve both coupling and scattering problems is an innovation in this paper. The relative size of the antenna is1.27 × 0.64 × 0.07λ
0
3, the working band is 4.28 GHz to 9.48 GHz, the relative bandwidth is 75.58%, and the isolation is increased to more than 16 dB. Other MIMO diversity parameters, such as envelope correlation coefficient (ECC), diversity gain (DG), mean effective gain (MEG), total active reflection coefficient (TARC), and channel capacity loss (CCL) are calculated and determined within the limits. The monostatic RCS reduction frequency band includes the in-band 6 GHz to 9.48 GHz and out-of-band 9.48 GHz to 22 GHz of the antenna, and the total relative bandwidth reaches 114.29%. In this paper, the metasurface improves the performance of antenna mutual coupling and scattering, and realizes the integrated design of metasurface antenna radiation and scattering, which is of great significance for antenna design.
Vibrational properties and lattice thermal conductivity of bulk and monolayer ZrS2 at finite temperatures
Authors: Li Wei , Xue Feng-ning , Zhao Peng-bo , Lu Yong 
Published: February 2025

Abstract
The traditional three-phonon scattering approach cannot adequately reflect the anharmonic phonon properties of the ZrS2 system due to its strong intrinsic anharmonicity. In this study, the vibrational properties and lattice thermal conductivity of both bulk and monolayer ZrS2 were investigated using large-scale machine learning force field molecular dynamics simulations and the anharmonic phonon approach, where all orders of anharmonic interactions between phonons caused by temperature were considered. At finite temperatures, the predicted Raman-active in-plane E
g
mode of the bulk phase ZrS2 decreases, while the inter-plane A1g
mode shifts to the blue, in agreement with experimental observations. Due to the competition between the chemical bond ionicity and phonon anharmonicity, the vibrational stiffness and frequency of the A1g
mode in monolayer ZrS2 exhibit inverse temperature-dependent behavior compared to the bulk phase. Phonon linewidths and scattering rates increase significantly with temperature, indicating stronger anharmonic interactions in ZrS2. The lattice thermal conductivity of bulk ZrS2 is significantly reduced when anharmonic phonon scattering beyond three-phonon processes is considered, with an average value of 1.91 ± 0.08 Wm−1K−1 at 300 K, which aligns with experimental results. Acoustic phonon modes dominate heat transport, with the lifetime of the TA mode being particularly temperature-sensitive. Monolayer ZrS2 exhibits enhanced lattice thermal conductivity, more than twice that of the bulk, due to the reduced unit cell volume and increased phonon lifetimes.
Sub-nanosecond threshold switching dynamics in GeTe4 ovonic threshold switching selector devices
Authors: Panneerselvam Sakthikumaran , Khan Salman , Manivannan Anbarasu 
Published: February 2025

Abstract
The threshold switching (TS) dynamics of Ovonic Threshold Switching (OTS) selector devices play a pivotal role in the programming speeds of Phase Change Random Access Memory (PCRAM) and Selector Only Memory (SOM). The TS phenomenon in amorphous selector devices rapidly reduces the initial high-resistance state to a low-resistance state within nanoseconds. In this work, we present a detailed experimental study of the time-resolved transient threshold switching characteristics of GeTe4 OTS devices, including measurements of delay time and holding voltage. The voltage-dependent delay time analysis reveals an exponential decrease in the delay time for the increase in the applied voltage above the threshold voltage. Moreover, the delay time rapidly decreased by an order for 10% increase over the steady-state threshold voltage. Furthermore, the lowest delay time of approximately 300 picoseconds was observed for the input voltage of 1.8 V, i.e. 50% higher than the steady state threshold voltage. These experimental findings on sub-nanosecond threshold switching dynamics in GeTe4 OTS devices pave the way for the development of high-speed PCRAM and SOM devices.