bluuebunny/crossref_metadata_2025 huggingface dataset:
Scour depth prediction around bridge abutments: A comprehensive review of artificial intelligence and hybrid models
Authors: Murtaza Nadir , Khan Diyar , Rezzoug Aïssa , Khan Zaka Ullah , Benzougagh Brahim , Khedher Khaled Mohamed
Published: February 2025

Scouring around the bridge structure is a major concern of the globe. Therefore, a precise estimation of the scour depth is essential to minimize bridge failure and provide preventive measures. This review paper aims to analyze the critical review of various artificial intelligence (AI) techniques utilized in the literature to estimate bridge abutment scour depth including artificial neural networks (ANN), adaptive neuro-fuzzy inference systems (ANFIS), gene expression programming (GEP), support vector machines (SVM), and extreme learning machines (ELM). The predictive power of each technique was assessed in terms of different performance indicators, such as correlation coefficient (R), mean square error (MSE), predicted values, Taylor's diagram, sensitivity analysis, and violin plot. This review paper highlights that by comparing different AI techniques, ELM and GEP techniques have superior performance, especially in predicting scour depth and dealing with complex and large datasets. However, various limitations and proposed solutions have been reported for techniques, such as ANN, ANFIS, SVM, and group method of data handling (GMDH). The main challenges in the ANN, ANFIS, SVM, and GMDH techniques were overfitting and hyperparameter tuning. Based on the performance of each technique, the current review paper found the satisfactory performance of the ELM technique because of its computation speed and precise estimation capability. Moreover, the proposed solutions would be helpful to researchers working in the field of hydraulics engineering, particularly scouring around the bridge abutment.
Band engineering for large perpendicular magnetocrystalline anisotropy and low magnetic Gilbert damping constant by anion substitution at Fe/MgO interface
Authors: Apriati Y.-N. , Nawa K. , Nakamura K.
Published: February 2025

Large interfacial perpendicular magnetocrystalline anisotropy (iPMA) and low Gilbert magnetic damping constant (α) in magnetic tunnel junctions (MTJs) are desired to achieve higher storage density and lower standby power operations in magnetic random-access memory. This work theoretically investigates effects of nitrogen and fluoride anions (N-anion and F-anion) substitution on the MgO barrier interface of Fe/MgO/Fe MTJ for iPMA and α using first-principles calculations. We find that the N-anion substitution significantly enhances iPMA by four times and reduces α by 65% compared to the pristine Fe/MgO/Fe, indicating a guideline toward an MTJ with large iPMA and low α simultaneously. The mechanism is explained by a band realignment at the Fermi level (EF) where Fe d±1 (dxz,dyz) orbitals at the interface are pushed above and below EF but Fe d±2 (dxy, dx2−y2) orbitals remain at EF by the N-anion substitution.
Tunable sliding ferroelectricity in two-dimensional van der Waals RuX2 (X = Cl, Br, and I) multiferroic layers
Authors: Han Peng , Zhang Jingtong , Chen Xumin , Wang Jie
Published: February 2025

Two-dimensional (2D) van der Waals (vdW) materials offer vast potential for designing ferroelectrics with desired properties through simple layer stacking. Here, based on first principles, we demonstrate that the vdW layered crystals RuX2 (X = Cl, Br, and I) are a class of 2D multiferroic sliding ferroelectrics. The stacking of two magnetic RuX2 monolayers with the same orientation breaks the spatial inversion symmetry, resulting in a stable vertical polarization. In addition, the direction of polarization can be reversed through slight interlayer sliding, in which it only needs to overcome the small energy barrier of 7.16 meV. Among these layered crystals, the bilayer RuI2 not only possesses a remarkable sliding ferroelectricity of 0.49 pC/m but also exhibits stable long-range magnetic order due to its large magnetic anisotropy energy. When the RuI2 stack is increased to trilayers, the polarization significantly increases to 1.03 pC/m, which is much larger than that of its bilayer structure. Furthermore, the application of compressive strain results in a substantial increase in vertical polarization. This work provides an efficient method for designing 2D multiferroic sliding ferroelectric materials by stack engineering.
Preparation and simulation of high-frequency lead-free NBBT/epoxy 1–3 piezoelectric composites with high electromechanical coupling characteristics
Authors: Li Lin , Ma Jinpeng , Zhou Xun , Liu Yaqi , Tang Yanxue , Wang Feifei , Zhang Qiaozhen , Yue Qingwen , Lin Di , Luo Haosu , Zhao Xiangyong
Published: February 2025

In this article, we design and fabricate (1 − x)Na0.5Bi0.5TiO3-xBaTiO3 single-crystal/epoxy 1–3 piezoelectric composites (NBBT 1–3 composites) with high coefficients of electromechanical coupling and demonstrate their considerable potential for use in high-frequency ultrasonic devices. We conducted finite element simulations on samples of the NBBT 1–3 composite to optimize their dimensional parameters. We used the cut-and-fill method to prepare an array of the NBBT-based 1–3 composite with a spacing of 20 μm between elements. It exhibited an exceptionally high coefficient of electromechanical coupling kt of 80.8%, with measured resonant and antiresonant frequencies of 11.6 and 18.5 MHz, respectively. Lead-free NBBT 1–3 composites that can deliver excellent performance are highly promising for use in medical applications of high-frequency ultrasound, especially for the brain–computer interface and intravascular ultrasound imaging.
Realizing sub-6-nm-channel high-performance spin field-effect transistors in lateral Sc2CHO/Sc2CHF/Sc2CHO heterojunctions
Authors: Wang Shao-Xian , Kong Ya-Qi , Wang Ming-Lang , Wei Ming-Zhi , Wang Chuan-Kui , Zhang Guang-Ping
Published: February 2025

In this work, nanoscale spin field-effect transistors (spin-FETs) based on lateral heterojunctions composed of two-dimensional (2D) ferromagnetic half-metallic Sc2CHO electrodes and nonmagnetic semiconductor Sc2CHF channel are theoretically designed. The channel lengths (Lc) for investigated nanoscale spin-FETs are shorter than 6 nm. The spin transport properties of these nanoscale spin-FETs are subsequently studied by using the nonequilibrium Green's function method in combination with density functional theory. Due to the strong electronic coupling at the interfaces between electrodes and channel, p-type Ohmic contacts are obtained for spin down. Calculations reveal that at very-low temperature, the spin injection efficiency can reach 100%, and the magnetoresistance ratio (MR) is generally larger than 109% for these nanoscale spin-FETs. Very-low subthreshold swing (SS) values below 60 mV/dec are found for spin-FETs with Lc≥ 4.05 nm, and the lowest SS value is 39 mV/dec for the spin-FET with Lc=5.75 nm. At room temperature, the values of MR exceed 106%, and the corresponding SS values are below 92 mV/dec with a minimum SS of 82 mV/dec, still demonstrating high performance for designed nanoscale spin-FETs. Our study provides valuable insights into the design of high-performance nanoscale spin-FET devices based on 2D MXenes.
Tailored slip length: Investigating the effect of solid–liquid interfacial tension
Authors: Pradhan Diva , Lee Jinseok , Prakash Ritesh , Chauhan Anuj , Lee Jinkee
Published: February 2025

By inducing non-zero fluid velocity on the surface wall, energy loss due to drag can be reduced due to slipperiness. The slippage due to molecular interactions is insignificant for most larger-scale applications. However, the presence of gas can potentially induce larger slippage that is related to solid–liquid interfacial tension. In the current work, we studied the influence of surface solid fraction (ϕs) and contact angle (θs) on slip length over micro-patterned surfaces. The surfaces have pillars with different ϕs fabricated by CO2 laser. The micro-pillars entrap air in between the structures, i.e., plastrons. The θs influences presence of additional gas over the solid surface due to interfacial tension. The slip length was calculated from shear stress measurements of the rheometer. The results show that the slip length dependence on ϕs follows the literature model for one-dimensional (1D) longitudinal grates (LG). Furthermore, a linear dependence of slip length on the cos(θs) was found, which has not been explored before for micro-patterned surfaces. Comparing experiment results with the predicted slip length shows an error of 6.9% (current correlation). The present study discusses the importance of surface's intrinsic energy on slip length for structured surfaces.
Advanced aerodynamic prediction software for versatile canard-controlled missile configurations
Authors: Theerthamalai P. , Mukesh R. , Praveenkumar M. , Prashanth M. , Rajput Arun , Krishna Mohan Rao R. , Hasan Inamul
Published: February 2025

The present research is aimed at the development of advanced aerodynamic prediction software for canard-controlled missile to handle versatile configurations. The prediction code has been developed for aerodynamic prediction for missile configurations based on analytical techniques and empirical relations. An equivalent angle of attack methodology has been used for the estimation of nonlinear behavior in aerodynamics. The code has the capability to handle arbitrary roll orientation including the interdigitated tail, dual control, and angle of attack up to 90°. Four papers were identified as references for validating the prediction method after a thorough review of the literature. The geometrical parameters of the missile from the reference paper are extracted and given as input to the prediction code to find the aerodynamic characteristics. The obtained data from the prediction code are compared with the experimental data from the reference paper. For all the cases, the basic characteristics have excellent validation. In most cases, the prediction deviation is within 1.0d on the longitudinal stability and within 15% of the normal force coefficient. There is a 20% difference in the tail control characteristics. The deviation in tail control effectiveness is within 20%. The deviation for canard control is within 30% and is primarily caused by the interaction of the canard vortex with the tail.
Weeds of the South-East
Authors: Richardson F. , Richardson R. , Shepherd R.
Published: February 2025

Weeds of the South-East is a comprehensive identification guide to weeds found in the South-East Region of Australia. This fourth edition has been updated to include recent changes in nomenclature, bringing all species and genus names in line with the current Australian Plant Census.

Beautifully illustrated, this guide is for anyone interested in the identification of pest plants and the preservation of our native flora. It is an essential tool for community land and bush care organisations, local and state government weed officers and advisers, rangers, agronomists, agriculturists, survey and identification botanists, horticulturists, landscapers and gardeners.
Increasing plant density increased rice (Oryza sativa) yield but decreased lodging resistance when grown under wheat (Triticum aestivum) straw using unmanned aerial seeding technology
Authors: Hu Qun , Zhu Haibin , Gu Yuankun , Wei Haiyan , Zhang Hongcheng
Published: February 2025

Context Unmanned aerial seeding (UAS) of rice (Oryza sativa) has inherent advantages, but may not achieve a high and stable yield when extensive stubble is returned. Aims This study aimed to determine the optimal planting density for achieving high yield and lodging resistance in UAS rice. Methods The experiment evaluated yield and lodging of two rice varieties (conventional japonica and hybrid indica–japonica) at four planting densities 105 (D1), 150 (D2), 195 (D3), and 240 (D4) seedlings m−2 for conventional japonica; 45 (D1), 82.5 (D2), 120 (D3), and 157.5 (D4) seedlings m−2 for hybrid indica–japonica). Key results Our results showed that yield initially increased and then decreased with increasing density, and the highest yield was obtained under treatment D3. Increasing planting density increased the proportion of main stem panicles and the effective panicles, but decreased the number of grains per panicle, seed setting rate, and 1000-grain weight. The population growth rate was lower in seeding-jointing and heading-maturity stages for treatments D1 and D2, higher in seeding-jointing stage for treatment D4 but insufficient in subsequent stages, while treatment D3 had higher population growth rate throughout the whole growth stage, especially in heading-maturity stages, ultimately achieving high yield. Densification led to a reduction in plant height and ear length, as well as slender internodes and thinner base wall. Conclusions A planting density of 195 seedlings m−2 was optimal for conventional japonica rice, and 120 seedlings m−2 for indica–japonica. Implications Achieving high yield of UAS rice can be facilitated by increasing planting density, but may compromise lodging resistance.
Weakening AMOC reduces ocean carbon uptake and increases the social cost of carbon
Authors: Schaumann Felix , Alastrué de Asenjo Eduardo
Published: February 2025

A weakening of the Atlantic Meridional Overturning Circulation (AMOC) has been found to be globally beneficial by economic assessments. This result emerges because AMOC weakening would cool the Northern Hemisphere, thereby reducing expected climate damages and decreasing estimates of the global social cost of carbon dioxide (SCC). There are, however, many other impacts of AMOC weakening that are not yet taken into account. Here, we add a second impact channel by quantifying the effects of AMOC weakening on ocean carbon uptake, using biogeochemically-only coupled freshwater hosing simulations in the Max Planck Institute Earth System Model. Our simulations reveal an approximately linear relationship between AMOC strength and carbon uptake reductions, constituting a carbon cycle feedback that leads to higher atmospheric CO
2
concentrations and stronger global warming. This AMOC carbon feedback, when incorporated into an integrated climate-economy model, leads to additional economic damages of several trillion US dollars and raises the SCC by about 1%. The SCC increase is similar in magnitude, but of opposite sign, to the SCC effect of Northern Hemisphere cooling. While there are many other potentially relevant economic impact channels, the AMOC carbon feedback alone could thus flip the consequences of AMOC weakening into a net cost to society.
RBM10 loss promotes metastases by aberrant splicing of cytoskeletal and extracellular matrix mRNAs
Authors: Krishnamoorthy Gnana P. , Glover Anthony R. , Untch Brian R. , Sigcha-Coello Nickole , Xu Bin , Vukel Dina , Liu Yi , Tiedje Vera , Pineda Jose Mario Bello , Berman Katherine , Tamarapu Prasanna P. , Acuña-Ruiz Adrian , Saqcena Mahesh , de Stanchina Elisa , Boucai Laura , Ghossein Ronald A. , Knauf Jeffrey A. , Abdel-Wahab Omar , Bradley Robert K. , Fagin James A.
Published: February 2025

RBM10 modulates transcriptome-wide cassette exon splicing. Loss-of-function RBM10 mutations are enriched in thyroid cancers with distant metastases. Analysis of transcriptomes and genes mis-spliced by RBM10 loss showed pro-migratory and RHO/RAC signaling signatures. RBM10 loss increases cell velocity. Cytoskeletal and ECM transcripts subject to exon inclusion events included vinculin (VCL), tenascin C (TNC), and CD44. Knockdown of the VCL exon inclusion transcript in RBM10-null cells reduced cell velocity, whereas knockdown of TNC and CD44 exon inclusion isoforms reduced invasiveness. RAC1-GTP levels were increased in RBM10-null cells. Mouse HrasG12V/Rbm1OKO thyrocytes develop metastases that are reversed by RBM10 expression or by combined knockdown of VCL, CD44, and TNC inclusion isoforms. Thus, RBM10 loss generates exon inclusion in transcripts regulating ECM–cytoskeletal interactions, leading to RAC1 activation and metastatic competency. Moreover, a CRISPR-Cas9 screen for synthetic lethality with RBM10 loss identified NFκB effectors as central to viability, providing a therapeutic target for these lethal thyroid cancers.
Splicing factor RBM10 loss fuels thyroid cancer metastasis
Authors: Coughlin Kevin , Wan Ledong
Published: February 2025

In this issue of JEM, Krishnamoorthy et al. (https://doi.org/10.1084/jem.20241029) identify the loss of the splicing factor RBM10 as a driver of metastasis in thyroid cancer through the regulation of RNA splicing. The synthetic lethal interaction between NF-κB and RBM10 loss reveals a potential therapeutic vulnerability.
Simultaneous estimation of electrical conductivity and permittivity in quantitative thermoacoustic tomography
Authors: Sahlström Teemu , Lahivaara Timo , Tarvainen Tanja
Published: February 2025

In this work, the inverse problem of quantitative thermoacoustic tomography is studied. In quantitative thermoacoustic tomography, dielectric parameters of an imaged target are estimated from an absorbed energy density induced by an externally introduced electromagnetic excitation. In this work, simultaneous estimation of electrical conductivity and permittivity is considered. We approach this problem in the framework of Bayesian inverse problems. The dielectric parameters are estimated by computing maximum a posteriori estimates, and the reliability of the estimates is studied using the Laplace's approximation. The forward model to describe electromagnetic wave propagation is based on a vectorial Maxwell's equation, that is numerically approximated using a finite element method with edge elements. The proposed methodology is evaluated using numerical simulations utilising one or two electromagnetic excitations at multiple excitation frequencies. The results show that the electrical conductivity and permittivity can be simultaneously estimated in quantitative thermoacoustic tomography. However, the problem can suffer from non-uniqueness, which could be overcome using multiple electromagnetic excitations.
Fundamental physical constants, operation of physical phenomena and entropy increase
Authors: Trachenko Kostya
Published: February 2025

Approaching the problem of understanding fundamental physical constants (FPCs) started with discussing the role these constants play in high-energy nuclear physics and astrophysics. Condensed matter physics was relatively unexplored in this regard. More recently, it was realised that FPCs set lower or upper bounds on key condensed matter properties. Here, we discuss a wider role played by FPCs in condensed matter physics: at given environmental conditions, FPCs set the observability and operation of entire physical effects and phenomena. We discuss structural and superconducting phase transitions and transitions between different states of matter. We also discuss metastable states, transitions between them, chemical reactions and their products. An interesting byproduct of this discussion is that the order of magnitude of the transition temperature can be calculated from FPCs. We show that the new states emerging as a result of various transitions increase the phase space and entropy. Were FPCs to take different values, these transitions would become inoperative at our environmental conditions and the new states due to these transitions would not emerge. This suggests that the current values of FPCs, by enabling various transitions and reactions which give rise to new states, promote entropy increase. We conjecture that entropy increase is a selection principle for FPCs considered to be variable in earlier discussions.
A Novel Two-Stage Fault Detection and Tracking Method of Hot-Melt Extrusion Process Based on Data-Driven Techniques
Authors: Zhang Mingjie , Chen Zhuyun , Deng Xu , Jin Gang
Published: February 2025

In the hot-melt extrusion (HME) process, process parameters play a crucial role in determining the quality of the extruded products. Abnormal processing parameters can lead to degraded product performance and quality inconsistencies. Therefore, real-time monitoring of the HME process is vital for maintaining product quality and consistency. However, most existing detection methods are limited in their application due to their material-specific nature. Moreover, when processing parameters vary only slightly, the corresponding changes in detection signals may not be significant, making it challenging to differentiate between normal and abnormal data. To address these challenges, this paper proposes a novel two-stage fault detection and tracking method for the HME process based on data-driven techniques. Firstly, comprehensive material detection is achieved by collecting and analyzing five types of data: near-infrared (NIR), Raman, ultrasound, melt pressure, and current. A GMV-KPCA anomaly detection model is then constructed to effectively identify four different abnormal conditions. T² and SPE statistical contribution maps are calculated to perform data dimensionality reduction and feature extraction. Subsequently, a CTRB-SVM anomaly localization model is developed. This model uses the extracted features as input and learns the mapping relationship between the five types of data and various abnormal situations to accurately locate the cause of the anomalies. Finally, experiments are conducted using HME process equipment to validate the proposed method. The experimental results demonstrate that the proposed two-stage fault detection and tracking method effectively identifies various faults and exhibits superior recognition performance compared to state-of-the-art methods. This method provides a robust solution for real-time monitoring and quality control in the HME process.
The impact of cross-layer movement on epidemic spreading in time-varying multiplex networks
Authors: Zeng Lang , Han Lilei
Published: February 2025

In the context of real-world multiplex networks, the movement of individuals across different layers introduced interlayer coupling, which signiﬁcantly affected diffusion processes within each layer. Additionally, the relationships among individuals undergo changes over time. Despite the abundant literature on the dynamics of propagation in complex networks, the impact of interlayer transitions (or interlayer jumps, interlayer shifts) on the spread of epidemics in activity-driven time-varying multiplex networks remains a relatively unexplored area. In this study, we introduced a time-varying two-layer network model that incorporated a subset of nodes known as inter-layer travelers, allowing them to move between different layers. We developed a theoretical framework based on the quenched mean-ﬁeld approximation, which yielded precise estimations of epidemic thresholds and ﬁnal states in both layers. Our ﬁndings indicated that the hopping behavior of interlayer travelers and the time-varying nature of the network impeded the disease transmission process. Furthermore, stronger heterogeneity in the individual activities could promote epidemic spread. However, the hopping behavior of interlayer travelers enhanced epidemic transmission in sub-networks with lower node activity heterogeneity while inhibiting it in sub-networks with higher node activity heterogeneity. Additionally, stronger contact capacity of nodes promoted disease spread, and interlayer traveler hopping promoted epidemic spreading in the sparse layer while suppressing it in the dense layer. Notably, an enhanced positive correlation between activities in the two layers can greatly suppress the spreading dynamics, suggesting a practical and effective approach to controlling epidemics in the real world.
Machine Learning Prediction and Experimental Validation of Microhardness in High-Entropy Alloy Reinforced Aluminium Composite
Authors: A Saravana Sundar , Radhika N.
Published: February 2025

This study introduces a novel approach for the prediction and experimental validation of microhardness in High Entropy Alloy (HEA) reinforced Aluminium composites using advanced Machine Learning (ML) techniques. For the first time, five ML models, including XGBoost, Stacking Regressor, Quantile Random Forest, Gaussian Process, and Sparse Polynomial Regression were employed to predict the microhardness of Al/HEA composites. The models were trained using an 80:20 train-test split, with hyperparameters optimized via random search and cross-validation. Among the models, XGBoost delivered the highest accuracy, with an R² value of 0.91, and predicted a microhardness of 177 HV. To validate these predictions experimentally, LM13 aluminium alloy was selected as the matrix material, reinforced with HEA (AlTiVZrCrMo) synthesized through stir casting route. Scanning Electron Microscopy (SEM) analysis confirmed uniform reinforcement distribution, contributing to an experimental microhardness of 168 HV, a 45% improvement over the base alloy. The minimal 5.8% deviation between predicted and experimental values demonstrates the effectiveness of ML in predicting material properties, significantly reducing the need for extensive experimental work.
FePt Small-grain Film with Au Doping for High Density Perpendicular Magnetic Recording Media
Authors: Zhang Li , Huang Zhicheng , Liu Caiyan , Lu Xikun , Xu Che , Li Chen
Published: February 2025

In this study, we focused on a FePtAu-C small-grain film specifically designed for very-high density perpendicular magnetic recording media, surpassing 1 Tbits/in2 density. The film layer had a composition of Fe47Pt43Au10-C40% with 7.2 nm thickness. It was deposited onto a silicon substrate with one 12nm thick magnesium oxide sandwich-layer at 560oC temperature. Notably, the film exhibited a perpendicular coercivity of 39 kOe. Based on transmission electron microscopy (TEM) analysis, the film small-grain size was determined to be approximately 8.2±1.6 nm. Furthermore, our investigation revealed that the grain size of magnesium oxide sandwich-layer was about 12 nm, which was larger than that of FePt. As a consequence, the FePt small-grains were not directly influenced by magnesium oxide small-grains beneath them. Moreover, a more in-depth examination using high-resolution TEM imaging demonstrated outstanding L10 ordering within the thin-film, corroborated by texture examination conducted via X-ray diffraction (XRD). It is noteworthy that magnesium oxide sandwich-layer exhibited a polycrystalline structure, while the FePt growing on top of magnesium oxide occurred in an epitaxial manner.
An ultra-high sensitivity methane gas sensor based on the vernier effect with cryptophane-A film deposited in the photonic crystal fiber
Authors: Zhou Di , Li Kaifeng , Zhang Sa , Li Shuguang
Published: February 2025

Methane gas, due to its high flammability, is convenient for people’s daily lives, but its flammability poses safety hazards. Methane tends to explode when mixed with air. Therefore, it is particularly important to be able to effectively detect methane gas concentrations. A new methane gas sensor is presented in this paper. It is extremely sensitive to the reaction of methane gas. It consists of two fiber Sagnac interferometer (SI) loops, which utilize the vernier effect. The two fiber SI loops remain parallel. The optical fiber structure of the effective sensing in the sensing SI loop and the effective sensing in the reference SI loop are the same. Both of them adopt the polarization-maintaining photonic crystal fiber (PM-PCF) designed in this paper. However, the sensing SI loop uses a two-step filling technique to block small air holes and an immersion technique to deposit methane gas sensitive film on large air holes in PM-PCF. The sensing capability of the methane gas sensor was evaluated utilizing the finite element method (FEM). The numerical simulation results show that under the condition of the concentration of methane gas in the environment is 0-3.5%, the average sensitivity of two parallel Sagnac loops is 260.86 nm/%. Compared with other fiber optic methane gas sensors, the sensitivity of the sensor designed by this scheme is significantly improved, which provides a valuable reference and direction for the development of new methods and the design of ultra-sensitive methane gas sensors.
A Study on the Radiation Effects on Flexible GaInP/GaAs/InGaAs Triple-Junction Solar Cells Using Photoluminescence Measurements
Authors: Aierken Abuduwayiti , Li Meng , Hamzawy Sameh , Bi Jinshun , Zhang Shuyi , Wang Tingbao , Liu Xuefei , Ma Teng
Published: February 2025

Herein, the photoluminescence (PL) measurements were used to study and investigate the degradation behavior of flexible GaInP/GaAs/InGaAs inverted metamorphic triple-junction (IMM3J) photovoltaics (PV) under 1 MeV electron irradiation. The changes in PL intensity with varying electron irradiation fluence enabled the acquisition of effective minority carrier lifetimes (τeff) for top GaInP, middle GaAs, and bottom InGaAs subcells under different irradiation conditions. Comparing the changes of τeff before and after the electron irradiation, it was found that the τeff of the InGaAs bottom subcell deteriorates most severely with increasing electron irradiation fluence. Based on the degradation behaviour of the solar cell output characteristics, it was confirmed that the overall performance degradation of the flexible GaInP/GaAs/InGaAs IMM3J solar cell is mainly due to the degradation of the current density of the InGaAs bottom subcell.
Fluctuation-driven synergy, redundancy, signal to noise ratio and error correction in protein allostery
Authors: Erman Burak
Published: February 2025

This study explores the relationship between residue fluctuations and molecular communication in proteins, emphasizing the role of these dynamics in allosteric regulation. We employ computational tools including the Gaussian Network Model, mutual information, and interaction information, to analyze how stochastic interactions among residues contribute to functional interactions while also introducing noise. Our approach is based on the postulate that residues experience continuous stochastic bombardment from impulses generated by their neighbors, forming a complex network characterized by small-world scaling topology. By mapping these interactions through the Kirchhoff matrix framework, we demonstrate how conserved correlations enhance signaling pathways and provide stability against noise-like fluctuations. Notably, we highlight the importance of selecting relevant eigenvalues to optimize the signal-to-noise ratio in our analyses, a topic that has yet to be thoroughly investigated in the context of residue fluctuations. This work underscores the significance of viewing proteins as adaptive information processing systems, and emphasizes the fundamental mechanisms of biological information processing. The basic idea of this paper is the following: Given two interacting residues on an allosteric path, what are the contributions of the remaining residues on this interaction. This naturally leads to the concept of synergy, redundancy and noise in proteins, which we analyze in detail for three proteins CheY, Tyrosine Phosphatase and β-Lactoglobulin.
Unveiling the role of high-order anharmonicity in thermal expansion: a first-principles perspective
Authors: Zhang Tianxu , Zhou Kun , Li Yingjian , Yi Chenhao , Faizan Muhammad , Fu Yuhao , Wang Xinjiang , Zhang Lijun
Published: February 2025

Thermal expansion is crucial for various industrial processes and is increasingly the focus of research endeavors aimed at improving material performance. However, it is the continuous advancements in first-principles calculations that have enabled researchers to understand the microscopic origins of thermal expansion. In this study, we propose a coefficient of thermal expansion (CTE) calculation scheme based on self-consistent phonon theory, incorporating fourth-order anharmonicity. We selected four structures (Si, CaZrF6, SrTiO3, NaBr) to investigate high-order anharmonicity's impact on their CTEs, based on bonding types. The results indicate that our method goes beyond the second-order quasi-harmonic approximation and thirdorder perturbation theory, aligning closely with experimental data. Furthermore, we observed that an increase in the ionicity of the structures leads to a more pronounced influence of high-order anharmonicity on CTE, with this effect primarily manifesting in variations of the Grüneisen parameter. Our research provides a theoretical foundation for accurately predicting and regulating the thermal expansion behavior of materials.
GraphSleepFormer: A multi-modal graph neural network for sleep staging in OSA patients
Authors: Wang Chen , Jiang Xiuquan , Lv Chengyan , Meng Qi , Zhao Pengcheng , Yan Di , Chao Feng , Xu Fangzhou , Lu Shanshan , Jung Tzyy-Ping , Leng Jiancai
Published: February 2025

Objective. Obstructive sleep apnea (OSA) is a prevalent sleep disorder. Accurate sleep staging is one of the prerequisites in the study of sleep-related disorders and the evaluation of sleep quality. We introduce a novel GraphSleepFormer (GSF) network designed to effectively capture global dependencies and node characteristics in graph-structured data. Approach. The network incorporates centrality coding and spatial coding into its architecture. It employs adaptive learning of adjacency matrices for spatial encoding between channels located on the head, thereby encoding graph structure information to enhance the model's representation and understanding of spatial relationships. Centrality encoding integrates the degree matrix into node features, assigning varying degrees of attention to different channels. Ablation experiments demonstrate the effectiveness of these encoding methods. The Shapley Additive Explanations (SHAP) method was employed to evaluate the contribution of each channel in sleep staging, highlighting the necessity of using multimodal data. Main results. We trained our model on overnight polysomnography data collected from 28 OSA patients in a clinical setting and achieved an overall Accuracy of 80.10%. GSF achieved performance comparable to state-of-the-art methods on two subsets of the ISRUC database. Significance. The GSF Accurately identifies sleep periods, providing a critical basis for diagnosing and treating OSA, thereby contributing to advancements in sleep medicine.
Helium plasma-induced surface modifications of unirradiated and pre-ion irradiated tungsten at LHD divertor leg position
Authors: Zhao Mingzhong , Masuzaki Suguru , Tokitani Masayuki , Yajima Miyuki , Kobayashi Makoto , Yabuuchi Kiyohiro , Oya Yasuhisa , Sakamoto Ryuichi
Published: February 2025

Understanding helium (He) plasma-induced tungsten (W) surface modifications, and the effect of irradiation defects on He plasma-induced W surface modifications under a real divertor environment are important for the operation of fusion reactors. In this study, two iron (Fe) ions pre-irradiated W samples with dislocation loops and voids, and two unirradiated W samples were exposed to He plasma at a divertor leg position of the Large Helical Device (LHD). The gross erosion rate are 1.0×1020 atoms m-2 s-1, 1.0×1020 atoms m-2 s-1, 9.3×1019 atoms m-2 s-1, 7.4×1019 atoms m-2 s-1 for W9, W10, W11, W12, respectively. The surface of each sample after the exposure was different at the strike point and the two regions on either side of the strike point, the scrape-off layer (SOL) region and the private region. The typical He plasma-induced structures at the SOL region were stripe structure, sawtooth structure, and no undulating structure, which are collectively called He-structures in the present study. At the strike point, the typical He plasma-induced structure was dense W protrusions. At the private flux region, the typical He plasma-induced structures are semi-formed He-structures. The formations of these structures were depended on the grain orientation. And pinholes were observed on these structures. No significant difference in the He plasma-induced structures was found between the pre-irradiated W and the unirradiated W. The formations of no undulating structure and stripe structure were discussed based on the observed semi-formed He-structures.
A metasurface-loaded low-scattering struts for sidelobe reduction in front-fed reflector antenna
Authors: Zhang Haozhi , Wang Zheng , He Yingran
Published: February 2025

A metasurface-loaded low-scattering strut has been proposed to reduce the radiation side lobe levels (SLLs) of front-fed reflector antennas. The H-shaped metasurface unit cells help to reduce the radar cross section (RCS) of metallic feed-support struts and finally reduce the SLLs. Compared to the metallic strut, the designed low-scattering strut reduced the forward RCS by 8.8 dB and the total RCS by 4.2 dB at 2.78 GHz. The technique is implemented in a 2 m S-band reflector antenna, and the SLL of the reflector antenna with the low-scattering struts is reduced by 4.0 dB compared to the reflector antenna with metallic struts. The reason for the significant SLL reduction in the reflector antenna utilizing low-scattering struts is explained. The simulation shows that, at 2.78 GHz, the SLL is lower than -21.8 dB. The result proves that the low-scattering strut design can be used to reduce the SLL on the front-fed reflector antenna.
Structural design and analysis of a robot joint integrated with brake
Authors: Cai Nianyu , Ju Hehua , Yang Yang
Published: February 2025

This paper proposes a novel robot joint with an integrated braking mechanism to enhance motion accuracy and flexibility. This joint design eliminates the need for additional bearings to support the motion shaft, resulting in lower cost and improved dynamic performance. A new dual-encoder installation method is employed in the design, which shortens the joint’s axial length and increases the radius of the optical grating without changing the joint’s outer diameter. Additionally, a newly designed electromagnetic brake is fully integrated within the joint, further improving compactness. Based on this design, finite element simulation is used to confirm the reliability of the joint’s support components and brake. Finally, a robotic joint experimental platform is constructed. The experimental results demonstrate that the joint exhibits excellent kinematic performance.
Study on the influence of oil-gas pressure difference on diaphragm in diaphragm compressor
Authors: Li Fengyu , Liu Xiaoming , Liu Zhilong , Yu Yang
Published: February 2025

As one of the main components of hydrogen refueling stations, the diaphragm hydrogen compressor is an important equipment supporting the development of hydrogen energy in China. Currently, the diaphragm hydrogen compressor is facing a significant demand for improving reliability. The diaphragm is one of the vulnerable parts in diaphragm hydrogen compressors, mainly affected by the difference between hydraulic oil pressure and hydrogen pressure, which deforms and compresses hydrogen gas to achieve the operation of diaphragm hydrogen compressors. This study selected the oil gas pressure difference as the independent variable and conducted simulation research on the variation laws of equivalent stress and axial deformation of the diaphragm.
Climate benefits of Amazon secondary forests – recent advances and research needs
Authors: Baker Jessica C.A. , Adami Marcos , Silva-Junior Celso H. L. , Sadeck Luis , Smith Callum , Heinrich Viola , Barlow Jos , Ferreira Joice , Cassol Henrique , Anderson Liana O. , von Randow Celso , Argles Arthur P. K. , von Randow Rita , Elias Fernando , Aragao Luiz E.O.C , Sitch Stephen , Spracklen Dominick V
Published: February 2025

A quarter of the deforested Amazon has regrown as secondary tropical forest and yet the climatic importance of these complex regenerating landscapes is only beginning to be recognised. Advances in satellite remote-sensing have transformed our ability to detect and map changes in forest cover, while detailed ground-based measurements from permanent monitoring plots and eddy-covariance flux towers are providing new insights into the role of secondary forests in the climate system. This review summarises how progress in data availability on Amazonian secondary forests has led to better understanding of their influence on global, regional and local climate through carbon and non-carbon climate benefits. We discuss the climate implications of secondary forest disturbance and the progress in representing forest regrowth in climate models. Much remains to be learned about how secondary forests function and interact with climate, how these processes change with forest age, and the resilience of secondary forest ecosystems faced with increasing anthropogenic disturbance. Secondary forests face numerous threats: half of secondary forests in the Brazilian legal Amazon were 11 years old or younger in 2023. On average, 1–2% of Amazon secondary forests burn each year, threatening the permanence of sequestered carbon. The forests that burn are predominantly young (in 2023, 55% of burned secondary forests were <6 years old, <4% were over 30 years old). In the context of legally binding international climate treaties and a rapidly changing political backdrop, we discuss the opportunities and challenges of encouraging tropical forest restoration to mitigate anthropogenic climate change. Amazon secondary forests could make a valuable contribution to Brazil’s Nationally Determined Contribution provided there are robust systems in place to ensure permanence. We consider how to improve communication between scientists and decision-makers and identify pressing areas of future research.
Precipitation leads the long-term vegetation increase in the conterminous United States drylands
Authors: Chang Yuhe , Winkler Alexander , Noori Amirhossein , Knyazikhin Yuri , Myneni Ranga
Published: February 2025

Drylands, encompassing over 40% of the conterminous United States (CONUS), are crucial to the global carbon cycle and highly susceptible to climate change. However, Earth system models offer conflicting projections of future drought and vegetation activity in North America, and in-depth analyses of the long-term changes in greenness and its relationship with underlying climate drivers, considering both spatial and temporal variations at the ecosystem scale, are lacking. This study analyzes 20-year (2001-2020) MODIS NDVI observations to assess greening trends in CONUS drylands and their relationship with climate drivers at 1km spatial resolution. Results indicate a large scale and systematic greening trend, particularly in the northern Great Plains (NGP) region. Using an empirical linear attribution approach and Empirical Orthogonal Function (EOF) analysis, we uncover varied relationships between greenness trends and climate drivers, particularly highlighting the dominant role of increased precipitation in driving the observed greening. Trend analysis reveals that while rain use efficiency (RUE) remains stable in most areas, increases in the NGP region suggest potential CO2 fertilization effects, while decreases in southern states correlate with rising temperatures. We also develop an efficiency-based model featuring RUE which successfully reproduces historical NDVI, re-confirming the dominant influence of precipitation in local greenness interannual variability. However, CMIP6 projections for 2021-2040 under the “Regional Rivalry” scenario (SSP370) paint a worrying picture, with projected browning in the NGP region and states near the 42°N latitude, contrasting recent greening trends. This potential reversal underscores the vulnerability of these ecosystems to future climate change, highlighting the need to consider both historical trends and future climate projections when assessing the resilience of drylands ecosystems. Overall, our work re-emphasizes the significance of water availability to drylands vegetation growth and contributes to a more comprehensive understanding of carbon-water cycling in arid and semi-arid regions.
Expectation values of conserved charges in Integrable Quantum Field Theories out of thermal equilibrium
Authors: Mazzoni Michele , Travaglino Riccardo , Castro-Alvaredo Olalla A
Published: February 2025

In this work we present a computation of the averages of conserved charge densities and currents of (1+1)-dimensional Integrable Quantum Field Theories in Generalised Gibbs Ensembles. Our approach is based on the quasi-particle description provided by the Thermodynamic Bethe Ansatz combined with the principles of Generalised Hydrodynamics, and we focus on Non-Equilibrium Steady State averages. When considering the ultraviolet (i.e. high temperature) limit of such averages, we recover the famous result by Bernard and Doyon (2012) for the energy current and density in Conformal Field Theories, and we extend it to conserved quantities with spin $s > 1$. We show that their averages are proportional to $T_L^{s+1}\pm T_R^{s+1}$, with $T_L$, $T_R$ the temperatures of two asymptotic thermal reservoirs. The same power law is obtained when considering some non-thermal generalised Gibbs states. In Conformal Field Theory, the power law is a consequence of the transformation properties of conserved charge operators, while the proportionality coefficient depends on the spin of the operator and on the central charge of the theory. We present an exact analytic expression for this coefficient in the case of a massive free fermion. At equilibrium, proportionality of spin-$s$ density averages to $T^{s+1}$ can be thought of as a generalisation of Stefan-Boltzmann's law, which states that the energy per unit surface area radiated by a black body scales as $T^4$.
High-Strength Concrete Enhancement Using Fine Metakaolin and Palm Oil Fuel Ash: A Comprehensive Study
Authors: Che Rahim N A N , Ismail M H , Abu Bakar M N R , George A F
Published: February 2025

The increased use of high-strength concrete in construction leads to significant carbon dioxide (CO2) emissions due to extensive cement manufacturing. To mitigate this, additives like fine metakaolin and palm oil fuel ash can enhance concrete performance and reduce the carbon footprint. In Stage 1, cement was partially replaced with 10%, 20%, and 30% FMK to find the optimal amount for further testing in Stage 2. The best-performing FMK mix was then combined with varying percentages of POFA (5%, 10%, and 15%) as cement replacement. Tests for slump, water absorption, compressive strength, flexural strength, and SEM analysis were conducted on concrete samples containing FMK and POFA. Initially, the FMK and POFA improved the concrete workability, but it declined with 20% to 30% FMK in Stage 1 and 20% FMK with 10% to 15% of POFA in Stage 2. The small particle sizes of FMK and POFA acted as fillers, reducing water absorption. The 20M5P mix demonstrated the highest compressive and flexural strengths and the lowest water absorption compared to the control sample and other mixes. Scanning electron microscopy analysis confirmed that FMK and POFA promoted a pozzolanic reaction involving alumina oxide, silica oxide, and calcium oxide with calcium hydroxide from cement, enhancing the hardening process of the concrete.