bluuebunny/crossref_metadata_2025 huggingface dataset:
Rossby waves with barotropic–baroclinic coherent structures and dynamics for the (2 + 1)-dimensional coupled cylindrical KP equations with variable coefficients
Authors: Yin Tianle , Du Yajun , Wang Weiqing , Pang Jing , Yan Zhenya
Published: September 2024

Starting from the classical quasi-geostrophic potential vorticity equation with equal depth two-layer fluid, the coupled cylindrical Kadomtsev–Petviashvili (KP) equations with variable coefficients for Rossby waves are studied. To be more general, the phase velocity is considered an indefinite integral about time and improves the analysis procedure. So the variable coefficients are obtained and some previous studies are reasonably explained. The cylindrical wave theory is therewith utilized to reduce the coupled cylindrical KP equations with variable coefficients, and based on the modified Hirota bilinear method, the lump solutions and interaction solutions are found. Through numerical simulations, the Rossby lump waves on both sides of the y axis move closer to the center, and their amplitude gradually decreases and tends to flatten with the generalized Rossby parameter growth. In the Rossby waves flow field, the dipole structures propagate to the east and lead to the appearance of the compress phenomenon during barotropic–baroclinic interaction. It is possibly useful for further theoretical research on atmospheric phenomena.
Saltbush seedlings (Atriplex spp.) shed border-like cells from closed-type root apical meristems
Authors: Gill Alison R. , Burton Rachel A.
Published: September 2024

Australian saltbush (Atriplex spp.) survive in exceptionally saline environments and are often used for pasture in semi-arid areas. To investigate the impact of salinity on saltbush root morphology and root exudates, three Australian native saltbush species (Atriplex nummularia, Atriplex amnicola, and Atriplex vesicaria) were grown in vitro in optimised sterile, semi-hydroponic systems in media supplemented with different concentrations of salt (NaCl). Histological stains and chromatographic techniques were used to characterise the root apical meristem (RAM) type and root exudate composition of the saltbush seedlings. We report that saltbush species have closed-type RAMs, which release border-like cells (BLCs). Monosaccharide content, including glucose and fructose, in the root mucilage of saltbush was found to be uniquely low, suggesting that saltbush may minimise carbon release in polysaccharides of root exudates. Root mucilage also contained notable levels of salt, plus increasing levels of unidentified compounds at peak salinity. Un-esterified homogalacturonan, xyloglucan, and arabinogalactan proteins between and on the surface of BLCs may aid intercellular adhesion. At the highest salinity levels, root cap morphology was altered but root:shoot ratio remained consistent. While questions remain about the identity of some components in saltbush root mucilage other than the key monosaccharides, this new information about root cap morphology and cell surface polysaccharides provides avenues for future research.
Transcription factor EGR2 alleviates autoimmune uveitis via activation of GDF15 to modulate the retinal microglial phenotype
Authors: Li Wanqian , He Siyuan , Tan Jun , Li Na , Zhao Chenyang , Wang Xiaotang , Zhang Zhi , Liu Jiangyi , Huang Jiaxing , Li Xingran , Zhou Qian , Hu Ke , Yang Peizeng , Hou Shengping
Published: September 2024

Uveitis is a vision-threatening disease primarily driven by a dysregulated immune response, with retinal microglia playing a pivotal role in its progression. Although the transcription factor EGR2 is known to be closely associated with uveitis, including Vogt–Koyanagi–Harada disease and Behcet’s disease, and is essential for maintaining the dynamic homeostasis of autoimmunity, its exact role in uveitis remains unclear. In this study, diminished EGR2 expression was observed in both retinal microglia from experimental autoimmune uveitis (EAU) mice and inflammation-induced human microglia cell line (HMC3). We constructed a mice model with conditional knockout of EGR2 in microglia and found that EGR2 deficiency resulted in increased intraocular inflammation. Meanwhile, EGR2 overexpression downregulated the expression of inflammatory cytokines as well as cell migration and proliferation in HMC3 cells. Next, RNA sequencing and ChIP-PCR results indicated that EGR2 directly bound to its downstream target growth differentiation factor 15 (GDF15) and further regulated GDF15 transcription. Furthermore, intravitreal injection of GDF15 recombinant protein was shown to ameliorate EAU progression in vivo. Meanwhile, knockdown of GDF15 reversed the phenotype of EGR2 overexpression–induced microglial inflammation in vitro. In summary, this study highlighted the protective role of the transcription factor EGR2 in AU by modulating the microglial phenotype. GFD15 was identified as a downstream target of EGR2, providing a unique target for uveitis treatment.
Determination of a small elliptical anomaly in electrical impedance tomography using minimal measurements
Authors: Chen Gaoming , Santosa Fadil , Titi Aseel
Published: September 2024

We consider the problem of determining a small elliptical conductivity anomaly in a unit disc from boundary measurements. The conductivity of the anomaly is assumed to be a small perturbation from the constant background. A measurement of voltage across two point-electrodes on the boundary through which a constant current is passed. We further assume the limiting case when the distance between two electrodes go to zero, creating a dipole field. We show that three such measurements suffice to locate the anomaly size and location inside the disc. Two further measurements are needed to obtain the aspect ratio and the orientation of the ellipse. The investigation includes the studies of the stability of the inverse problem and optimal experiment design.
Normalizing flow regularization for photoacoustic tomography
Authors: Wang Chao , Thiery Alexandre H
Published: September 2024

Proper regularization is crucial in inverse problems to achieve high-quality reconstruction, even with an ill-conditioned measurement system. This is particularly true for three-dimensional photoacoustic tomography (PAT), which is computationally demanding and requires rapid scanning, often leading to incomplete measurements. Deep neural networks, known for their efficiency in handling big data, are anticipated to be adept at extracting underlying information from images sharing certain characteristics, such as specific types of natural or medical images. We introduce a normalizing flow-based regularization (NFR) method designed to reconstruct images from incomplete and noisy measurements. The method involves training a normalizing flow network to understand the statistical distribution of sample images by mapping them to Gaussian distributions. This well-trained network then acts as a regularization tool within a Bayesian inversion framework. Additionally, we explore the concept of adaptive regularization selection, providing theoretical proof of its admissibility. A significant challenge in three-dimensional image training is the extensive memory and computation requirements. We address this by training the normalizing flow model using only small-size images and applying a patch-based model for reconstructing larger images. Our approach is model-independent, allowing the reuse of a well-trained network as regularization for various imaging systems. Moreover, as a data-driven prior, NFR effectively leverages the available dataset information, outperforming artificial priors. This advantage is demonstrated through numerical simulations of three-dimensional PAT under various conditions of sparsity, noise levels, and limited-view scenarios.
A high-performance compact WR-4 orthomode transducer for wideband communications
Authors: Zhang Xiaojian , Yang Hao , Zhou Ren , He Yue , Huang Kun , Cen Jina , Tian Yaoling , Jiang Jun
Published: September 2024

This paper presents the design, fabrication and performance evaluation of a compact orthomode transducer (OMT) optimized for wideband communications. The OMT developed in this work features a circular waveguide as its common port, ensuring direct compatibility with receivers such as horn antennas, meanwhile enabling dual-polarization capabilities. The operational frequency spectrum of the OMT spans the entire WR-4 band (170 GHz–260 GHz), achieving reflection coefficients surpassing 20 dB and port isolation better than 60 dB, as validated through electromagnetic simulations. To evaluate performance of the fabricated OMT in a practical dual-polarization system, the OMT is utilized as the feed source for a horn antenna to realize a dual-polarized horn antenna system. The results demonstrate that the antenna incorporating the OMT exhibits superior performance, with average reflection coefficients close to 25 dB and port isolation exceeding 40 dB for overall operational band. These results indicate that the OMT developed in this work successfully meets the demanding requirements for polarization multiplexing in wideband dual-polarized receiver systems.
Explanation of puzzling FQHE at the filling fraction 3/4 in a band-hole 2D system in GaAs
Authors: Jacak J E
Published: September 2024

A recent experiment revealed an unexpected FQHE at filling fraction 3/4 in a GaAs 2D hole system, which contradicts the composite fermion model prediction and the observation of a compressible Hall metal-type state in a twin 2D electron system in GaAs at the same filling fraction 3/4 at almost same other conditions. This finding challenges conventional effective single-quasiparticle model for FQHE exposing its limitations. We explain this experimental observation within a multiparticle approach based on a topological cyclotron commensurability criterion. This allows to generalize Laughlin function for filling fractions from the complete FQHE hierarchy including observable FQHE states at even denominator fractions. The topological multiparticle approach helps to decipher a structure of composite fermions and provides their generalization for so-called enigmatic states including even denominator filling fractions, and also for quantum fractional Hall-type behavior in Chern topological insulators without a magnetic field.
A novel rehabilitation action recognition approach using AF-LiteFormer from millimeter wave radar
Authors: Yi Jiangang , Zou Hongfeng , Yuan Rui , Gao Jun , Fu Shiyu
Published: September 2024

Rehabilitation action recognition is a hot research topic in the medical field, which serves as the foundation for achieving remote healthcare, unsupervised exercise, intelligent home healthcare, and possesses extensive application value. Currently, vision-based action recognition methods are susceptible to limitations imposed by factors such as range of motion and environmental lighting during human motion capture. Due to its ability to effectively protect patient privacy and its immunity to lighting conditions, this paper proposed a millimeter-wave radar-based rehabilitation action recognition system, AF-LiteFormer. Firstly, EfficientFormerV2 is employed as the baseline, then a Lite-MSLA-FFN block-and-layer is designed to replace MHSA in EfficientFormerV2, which improves the diversity of attention and reduces computational complexity. Meanwhile, a Lite-Subsample block-and-layer is designed to replace the dual-path downsampling part that composed of attention downsampling and stride attention to realize global modeling and multi-scale learning. Secondly, the iterative attention feature fusion mechanism is introduced to learn rich feature representation for improving the recognition accuracy of rehabilitation actions. Finally, the effectiveness of the AF-LiteFormer model is validated on a self-collected rehabilitation action dataset and a publicly available micro-Doppler dataset. Experimental results show that the overall performance of the AF-LiteFormer model is better than the state-of-the-art models, the recognition accuracy of rehabilitation actions is as high as 99.7%, and it has strong generalization ability.
An iterative learning-based integrated motion planning and control method for autonomous patrolling of unmanned surface vehicles
Authors: Tang Yun , Wu Fei , Gong Xinle , Chen Chao , Liu Hongliang , Ma Jie , Qin Yi , Pu Huayan , Luo Jun
Published: September 2024

The minimization of maritime patrol durations and the optimization of patrol trajectories are still a prevailing challenge for autonomous navigation of unmanned surface vehicles (USVs). In this paper, we propose an integrated trajectory planning and control method to achieve time-optimal autonomous patrol of USVs by a data-efficient iterative learning-based predictive control algorithm. We build the optimization problem of the algorithm by introducing a local cost and a local safe constraint set for closed-loop efficient data-driven learning. To guarantee recursive feasibility, stability and convergence properties of the optimization algorithm at each iteration, the local cost and the local constraint set are designed and update iteratively using the historical vehicle states at previous iterations as a dataset. Different from traditional optimization methods, the proposed method does not require a reference path. The cost function of the optimization method decreases monotonically and converge to obtain a time-optimal control law for trajectory planning and tracking of USVs only after several iterations. The proposed approach is validated on the robotic operation system in typical maritime patrol scenarios. The results show that the proposed method implement a 5% reduction of patrol time, fewer lateral track errors, and smoother trajectories compared to the traditional MPC algorithm under water flow conditions. In addition, Enhancements in patrol operation efficiency of USVs are achieved by the algorithm, even under the constraints of varied patrol paths, attesting to its versatility.
Research on power metering method for nonlinear loads in power system based on improved S-transform
Authors: Li Long , Li Rui , Qu Guang
Published: September 2024

Traditional power metering algorithms are no longer suitable for new power systems to address the issue of distorted voltage and current waveforms caused by a growing number of nonlinear loads in modern power systems. The paper proposes a power-metering algorithm based on an Improved Stockwell Transform (IST). Based on the Stockwell transform, several parameters that can control the Gaussian window are introduced to improve the flexibility of the Gaussian window. Additionally, the inequality constraint based on the energy concentration measure is used to optimally select the best window parameters, enhancing the time–frequency domain analysis capability of the IST. The study uses IST to decompose and reconstruct the voltage and current fundamental characteristic signals and distortion characteristic signals in the power system. This provides good time resolution at low frequencies and good frequency-domain resolution at high frequencies. Power metering based on unsteady voltage and current is achieved by calculating the resulting fundamental and harmonic powers, respectively. The simulation results demonstrate that the IST-based power metering method has a higher level of accuracy than the existing metering methods.
Suppression of the interference fading in heterodyne Φ-OTDR with fast signal synthesis algorithm
Authors: Xu Deyu , Yu Feihong , Liu Shuaiqi , Gu Huaxin , Chen Xingwei , Zhang Jingming , Mu Qi , Yang Xiongji , Zhang Haifeng , Shao Liyang
Published: September 2024

With the increasing diversity of application scenarios, there is a growing demand for distributed acoustic sensing (DAS) systems to monitor the environment without false alarms. In DAS system based on phase-sensitive optical time-domain reflectometry (Φ-OTDR), interference fading significantly lead to a large number of false alarms in the system, which affecting the system’s monitoring capability. Before the phase demodulation process, Φ-OTDR system generally requires additional time for interference fading suppression. Therefore, the rapid acquisition of a fading-free signal before phase demodulation benefits the use of Φ-OTDR in real-time demanding scenarios. In this paper, based on the time-domain stitching and complex-field moving average, a fast signal synthesis (FSS) algorithm is proposed, enabling the quick synthesis of signals while maintaining fading suppression performance. Experimental results show that the signal intensity obtained by FSS algorithm fluctuates within 27 dB, while the intensity of the conventional denoising algorithm fluctuates more than 50 dB. Meanwhile, this method is more rapid than the rotated-vector-sum (RVS) algorithm, and the time consumption of signal synthesis is only 26.58% of that of the RVS algorithm. FSS algorithm provides a new and faster way to synthesize signals for interference fading suppression. Benefiting from this, FSS algorithm further improves the real-time performance of the Φ-OTDR system.
Heteroatom doped graphitic carbon nanotubes as freestanding anodes for advanced potassium-ion batteries
Authors: Liu Jiaqi , Wu Hanfeng , Tang Jiping , Jiang Le , Wang Zhenhan , Yuan Yongjun , Bai Wangfeng , Shi Xiaowei , Wu Shiting
Published: September 2024

Owing to its higher earth element reserve and similar chemical properties to lithium, potassium ion batteries (PIBs) have been regarded as a potential alternative to lithium-ion batteries. And considering the relatively larger ionic radius of potassium, available electrode materials need to be equipped with enough space for volume expansion during charge–discharge cycles, thus graphitic carbon nanomaterials with adjustable layer spacing gradually come into researcher’s version. Here with copper nanowires serving as growth template and organic polyvinyl pyrrolidone (PVP) providing carbon source, freestanding and ultra-light graphitic carbon nanotube (GCNT) aerogels were simply assembled and annealed, which were directly used as anodes of PIBs. Annealing parameters (temperature and atmosphere) were adapted to regulate the lattice order and interlayer spacing of GCNTs, and N, O heteroatoms derived from PVP were directly doped into the carbon lattice during thermal annealing, to optimize and enhance the cycle capacity and rate performance of GCNT anodes. The electrochemical potassium storage mechanism of GCNTs was also quantitatively analyzed. Most of the potassium ions are reversibly stored by squeezing into and escaping from the carbon lattice, and simultaneously oxygen-containing functional groups with different chemical states also offer active redox sites and dedicate partial capacity. Therefore, our assembled GCNTs with large lumen are expected to sandwich-like load with active substances efficiently, further constructing next-generation PIBs with excellent performance.
Non-radiative recombination centres in InGaN/GaN nanowires revealed by statistical analysis of cathodoluminescence intensity maps and electron microscopy
Authors: Quach Anh My Nhat , Rochat Névine , Rouvière Jean-Luc , Napierala Jérôme , Daudin Bruno
Published: September 2024

The methodology of statistical analysis of cathodoluminescence (CL) intensity mappings on ensembles of several hundreds of InGaN/GaN nanowires (NWs) used to quantify non-radiative recombination centres (NRCs) was validated on InGaN/GaN NWs exhibiting spatially homogeneous cathodoluminescence at the scale of single NWs. Cathodoluminescence intensity variations obeying Poisson’s statistics were assigned to the presence of randomly incorporated point defects acting as NRCs. Additionally, another type of NRCs, namely extended defects leading to spatially inhomogeneous cathodoluminescence intensity at the scale of single InGaN/GaN NWs are revealed by high resolution scanning transmission electron microscopy, geometrical phase analysis and two-beam diffraction conditions techniques. Such defects are responsible for deviations from Poisson’s statistics, allowing one to achieve a rapid evaluation of the crystallographic and optical properties of several hundreds of NWs in a single cathodoluminescence intensity mapping experiment.
Real-time delivered dose assessment in carbon ion therapy of moving targets
Authors: Galeone C , Steinsberger T , Donetti M , Martire M C , Milian F M , Sacchi R , Vignati A , Volz L , Durante M , Giordanengo S , Graeff C
Published: September 2024

Objective. Real-time adaptive particle therapy is being investigated as a means to maximize the treatment delivery accuracy. To react to dosimetric errors, a system for fast and reliable verification of the agreement between planned and delivered doses is essential. This study presents a clinically feasible, real-time 4D-dose reconstruction system, synchronized with the treatment delivery and motion of the patient, which can provide the necessary feedback on the quality of the delivery. Approach. A GPU-based analytical dose engine capable of millisecond dose calculation for carbon ion therapy has been developed and interfaced with the next generation of the dose delivery system (DDS) in use at Centro Nazionale di Adroterapia Oncologica (CNAO). The system receives the spot parameters and the motion information of the patient during the treatment and performs the reconstruction of the planned and delivered 4D-doses. After each iso-energy layer, the results are displayed on a graphical user interface by the end of the spill pause of the synchrotron, permitting verification against the reference dose. The framework has been verified experimentally at CNAO for a lung cancer case based on a virtual phantom 4DCT. The patient’s motion was mimicked by a moving Ionization Chamber (IC) 2D-array. Main
results. For the investigated static and 4D-optimized treatment delivery cases, real-time dose reconstruction was achieved with an average pencil beam dose calculation speed up to more than one order of magnitude smaller than the spot delivery. The reconstructed doses have been benchmarked against offline log-file based dose reconstruction with the TRiP98 treatment planning system, as well as QA measurements with the IC 2D-array, where an average gamma-index passing rate (3%/3 mm) of 99.8% and 98.3%, respectively, were achieved. Significance. This work provides the first real-time 4D-dose reconstruction engine for carbon ion therapy. The framework integration with the CNAO DDS paves the way for a swift transition to the clinics.
Influence of the magnetic field on the emission of hot electrons and ions from ablative plasma produced from a disc-coil target irradiated by the 3rd harmonic of the PALS iodine laser
Authors: Pisarczyk T , Renner O , Rusiniak Z , Dudzak R , Domanski J , Rafalak W , Chodukowski T , Badziak J , Krupka M , Singh S , Tchórz P , Rosinski M , Krasa J , Agraval S , Klir D , Cikhardt J , Zaras-Szydłowska A , Dostal J , Ettel D , Vlachos C , Ehret M , Bradford P W , Marchenko H , Gajdos P , Szymanski M , Jelinek S , Miklaszewski R , Batani D , Batani K , Santos J , Ospina-Bohórquez V , Volpe L , Borodziuk S , Krus M , Juha L
Published: September 2024

Experimental and theoretical study of plasma processes affected by strong laser generated magnetic fields is reported. The PALS laser system operating at 3 ω (438.5 nm) delivered intensities up to 1 × 1016 W cm−2 on targets. By using a special target system consisting of a Cu foil connected to a sub-mm coil, magnetic fields up to the level of 10 T were generated. This is 1.4 times higher than the field generated with a 1.315 mm (1 ω) laser beam at a comparable intensity. We found that these fields were sufficiently strong to modify plasma blow-off from the foil which resulted in the changed expansion dynamics and increased energy of hot electrons (HE) by 20%–40% compared to the plasma unaffected by the magnetic field. To obtain complementary experimental data, a complex diagnostic system was used enabling the visualization of the plasma expansion process both in visible light (3-frame composite interferometry) and in the soft x-ray region (4-frame pinhole x-ray camera) together with measurements of the HE parameters using two-dimensional imaging of the Kα line emission from the Cu target and electron spectroscopy. Experimental data obtained from the angular distribution of electron energy spectra were used for three-dimensional (3D3V) numerical PIC simulations using a modified EPOCH code. By including interactions between ions, protons, hot and thermal electrons in forward and backward propagating particles, the effects of the magnetic field on the flux of HE were visualized and compared with the experiment. The PIC simulation confirmed that the interaction of the HE flux with the magnetic field generated by the target-coil system leads to an increased flux energy. However, this increase is accompanied by increased complexity of the spatial structure and heterogeneity of the flux as well as its angular divergence.
Exact results of the one-dimensional repulsive Hubbard model
Authors: Luo Jia-Jia , Pu Han , Guan Xi-Wen
Published: September 2024

We present analytical results of the fundamental properties of the one-dimensional (1D) Hubbard model with a repulsive interaction. The new model results with arbitrary external fields include: (I) using the exact solutions of the Bethe ansatz equations of the Hubbard model, we first rigorously calculate the gapless spin and charge excitations, exhibiting exotic features of fractionalized spinons and holons. We then investigate the gapped excitations in terms of the spin string and the

k
−
Λ

string bound states at arbitrary driving fields, showing subtle differences in spin magnons and charge

η

-pair excitations. (II) For a high-density and high spin magnetization region, i.e. near the quadruple critical point, we further analytically obtain the thermodynamic properties, dimensionless ratios and scaling functions near quantum phase transitions. (III) Importantly, we give the general scaling functions at quantum criticality for arbitrary filling and interaction strength. These can directly apply to other integrable models. (IV) Based on the fractional excitations and the scaling laws, the spin-incoherent Luttinger liquid (SILL) with only the charge propagation mode is elucidated by the asymptotic of the two-point correlation functions with the help of conformal field theory. We also, for the first time, obtain the analytical results of the thermodynamics for the SILL. (V) Finally, to capture deeper insights into the Mott insulator and interaction-driven criticality, we further study the double occupancy and propose its associated contact and contact susceptibilities, through which an adiabatic cooling scheme based upon quantum criticality is proposed. In this scenario, we build up general relations among arbitrary external- and internal-potential-driven quantum phase transitions, providing a comprehensive understanding of quantum criticality. Our methods offer rich perspectives of quantum integrability and offer promising guidance for future experiments with interacting electrons and ultracold atoms, both with and without a lattice.
Optimizing CuInSe2 solar cells with kesterite-based upper absorber and back surface field layers for enhanced efficiency: a numerical study
Authors: Belkacem Izzeddine , Bensmaine Souhila , Belarbi Mousaab , Merzouk Chams El Hayat
Published: September 2024

This study explores the performance enhancement of an innovative multi-layer solar cell structure using the SCAPS-1D (Solar Cell Capacitance Simulator in One Dimension) software. We aim to improve the efficiency of a solar cell structure comprising ZnO/ZnSe/CZTSe/ CuInSe2/CZTSSe/Mo by incorporating CZTSe as the upper absorber layer, CuInSe2 as the main absorber layer, and CZTSSe as a back surface field layer. Initially, we compare the performance of three different configurations by analyzing their J–V characteristics. For the best performing structure, we further examine the external quantum efficiency spectrum. We then evaluate various window (ZnO, ZnMgO, SnO2, Zn2SnO4) and buffer (ZnSe, ZrS2, SnS2, In2S3) materials, identifying ZnO and ZrS2 as the most effective for achieving high current density and efficiency. Through detailed simulations, we determine the optimal thicknesses for CZTSSe (0.2 µm), CZTSe (0.4 µm), and CuInSe2 (3.2 µm). Additionally, by optimizing the acceptor density to 1020 cm−3, we significantly enhance the performance of both CZTSe and CZTSSe layers. Temperature management is shown to be crucial, with the highest efficiency observed at 300 K. As a result of these optimizations, the solar cell structure achieves a remarkable efficiency of 35.38%. Furthermore, we compare our results with existing literature to highlight the advancements made in this study. These findings underscore the importance of material selection and structural optimization in developing high-efficiency solar cells and provide a framework for future advancements in photovoltaic technology.
Dielectric modulated TFET on SELBOX substrate as a label-free biosensor applications: analytical modeling study and sensitivity analysis
Authors: Singh Ashish Kumar , Kumar Ramesh , Jit Satyabrata
Published: September 2024

The manuscript proposes a ferroelectric heterojunction TFET (BG-FE-HJ-STFET) on SELBOX substrates with a back gate to create an ultra-sensitive label-free biosensor with dielectric modulation for the detection of neutral and charged biomolecules. Within the proposed device, four cavities have been carved out for the biomolecules’ immobilization under the front and rear gate dielectrics. By using a ferroelectric (FE) material as a gate stack, the low gate voltage is increased to be more effective by causing a negative capacitance phenomenon. The response of the proposed biosensor to four impartial biomolecules with different dielectric constants: protein (k = 8), biotin (k = 2.63), 3-Aminopropyl-triethoxysilane (APTES) (k = 3.57), and streptavidin (k = 0.1) has been investigated. Deoxyribonucleic acid (DNA), a charged biomolecule, is also examined for the dielectric constant of k = 6 concerning both charge (negative and positive) densities. The device is simulated with the commercially available SILVACO ATLASTM TCAD tool. The performance analysis relies on several figures of merit (FOMs) such as DC/RF and sensitivity (including drain current, I

ON

/I

OFF
ratio, and subthreshold swing) for both neutral and charged biomolecules. The optimized cavity structure demonstrates a notable sensitivity in drain current (2.7 × 108) and a significant I

ON

/I

OFF
sensitivity (1.42 × 1011). One of the main problems with current biosensors is the difficulty and expense of production in the nanoscale realm.
Analysis of 11B + 13,14C scattering and 13C(11B, 10B)14C reaction data at E
lab(11B) = 45 MeV using energy dependent optical model systematics for carbon isotopes
Authors: Mezhevych S Yu , Ponkratenko O A , Rudchik A T , Keeley N , Kemper K W , Rudchik A A , Rusek K , Uleshchenko V V , Stepanenko Yu M , Koshchiy E I , Shyrma Yu O
Published: September 2024

Existing data for 11B + 13,14C elastic and inelastic scattering at E
lab(11B) = 45 MeV, as well as new data for the 13C(11B, 10B)14C reaction for transitions populating the ground state of 14C and the ground plus first four excited states of 10B, were analysed using the coupled-channels (CC) and coupled-reaction-channels (CRC) methods. A recently proposed energy dependent optical model (OM) potential for carbon isotopes, consisting of Woods-Saxon (WS) volume real and WS volume plus surface imaginary components, applied successfully to OM analyses of scattering from mid-mass (A > 27) and heavy target nuclei, was used to generate the distorted waves in the entrance and exit channels. The data analysed in this work cover the whole angular range, enabling the most important reaction mechanisms leading to the production of nuclei in the exit reaction channels to be established. For these light boron + carbon systems, a reasonable fit to both scattering and reaction data over the full angular range required some modification of the parameters of the OM potential extracted from the energy-dependent carbon systematics: omission of the surface imaginary part and a slight increase in the radius of the real part. Inclusion of a sufficient number of inelastic channels in a CC analysis of the 11B + 13,14C elastic scattering was shown to be important at mid-range scattering angles, while for the 13C(11B, 10B)14C reaction inclusion of two-step neutron transfers via low-lying excited states of 11B was required to give good overall agreement between the CRC calculations and the data. We suggest the analytical form of the global carbon OM potential may benefit from an additional parameterization of the radius of the real part and the depth of the surface imaginary part, dependent on the target mass number, to give better applicability to the analysis of scattering from light target nuclei.
(Ti,W)C Morphology prediction & (Ti,W)C/Ni Interface bonding characteristics analysis based on first principles and experimental verification
Authors: Yao Fangping , Yu Senhao , Li Jinhua , Pan Wenpeng
Published: September 2024

In order to ensure the feasibility of preparing (Ti,W)C composite ceramic reinforced Ni-based coating by laser cladding, the first principle was used to caculate the electronic structure of (Ti,W)C and predict its morphology. The interface bonding properties of (Ti,W)C/Ni were analyzed through interface construction, and the temperature conditions for in situ formation of (Ti,W)C composite ceramics were obtained through thermodynamic analysis. The in situ preparation of (Ti,W)C/Ni composite coatings was conducted through cladding experiment. The microstructure of the coating was detected by SEM, and the crystal morphology and element composition were analyzed to verify the accuracy of (Ti,W)C morphology prediction. The microhardness of the coating was measured by Vickers hardness tester. The results show that (Ti,W)C composite ceramics can be prepared in situ by laser cladding, and its morphology is hexagon-like. The interface of (Ti,W)C and Ni matrix is well combined, and there are no obvious porosity, cracks and other defects. The (Ti,W)C grains in the coating are fine and uniform.
Design and investigation of indium tin oxide-based transparent broadband microwave absorbers
Authors: Pan Ze-Yu , Wu Hai-Bin , Tian Ye , Lv Bo
Published: September 2024

This paper presents the design of a novel wideband transparent microwave absorber based on indium tin oxide (ITO). The absorber adopts a multilayer structure, with the top layer composed of a nested square structure made of ITO material, an intermediate dielectric layer of polyvinyl chloride (PVC), and a bottom layer of polyethylene terephthalate (PET) coated with ITO as the reflector. By optimizing structural parameters such as the thickness of the ITO film and the dimensions of the spacer layer, efficient broadband microwave absorption exceeding 90% is achieved within the frequency range of 2.43 to 5.67 GHz, while simultaneously meeting requirements for optical transparency and broadband performance. Simulation experiments and theoretical analyses demonstrate excellent polarization and incident angle stability of the absorber structure. Finally, samples are fabricated using screen printing technology, and free-space testing results are consistent with simulation predictions, validating the feasibility of the design.
A compact low-profile substrate integrated waveguide wearable filtenna for 5G communication
Authors: Kumar Abhijeet , Sriwas S K , Kumar Mahendra , Bharti Archana
Published: September 2024

We have proposed the design and synthesis of a compact, low-profile, flexible substrate integrated waveguide (SIW) wearable filtering antenna (filtenna) for 5 G communication, along with two parasitic resonator patches. We initially used a half-mode rectangular-shaped substrate-integrated (HMRSI) cavity as a resonating patch to minimize circuit size. The HMRSI cavity is located in close proximity to two parasitic truncated corner patches that serve as both the radiator and the final stage resonators, thereby optimizing filtering performance and expanding the operating bandwidth. The interaction of the parasitic patches with the HMRSI cavity produces one radiation null at the upper band-edges, while the corner truncation and notching on the parasitic patches with defected ground creates the other, enhancing the roll-off rate. Typical filter synthesis technology guides the design of the antenna. We have manufactured and measured an optimized prototype. The proposed flexible filtenna demonstrates excellent out-of-band selectivity, and its measurement aligns well with simulated ones, achieving an 8.2% fractional bandwidth (FBW), a maximum realized gain of 6.1 dBi, and a flat passband gain response. The proposed filtenna has also studied the human body and achieved a low specific absorption rate (SAR), which enables it to be an on-body wearable filtenna.
Impossibility of rips and cosmological singularities in a universe merging with baby universes
Authors: Trivedi Oem , Khlopov Maxim
Published: September 2024

Understanding the late-time acceleration of the universe and its subtleties is one of the
biggest mysteries in cosmology. A lot of different approaches have been put forward to deal with
this, ranging from the conventional cosmological constant to various models of dark energy and
beyond. Recently one very interesting approach to explaining the late time acceleration has been
put forward, where the expansion of the universe is driven by mergers with other “baby”
universes and has been shown to be quite viable as well from the point of view of recent
observational data. So in this work we examine the possibility of various rip scenarios and other
future cosmological singularities in such “multiversal” scenario, probing such singularities for
the first time in a multi universe scenario. We examine two models of such a baby universe merging
cosmology, and show that remarkably no rip scenario or future cosmological singularity is possible
in such models.
The glow of axion quark nugget dark matter. Part I. Large scale structures
Authors: Majidi Fereshteh , Liang Xunyu , Waerbeke Ludovic Van , Zhitnitsky Ariel , Sekatchev Michael , Sommer Julian S. , Dolag Klaus , Castro Tiago
Published: September 2024

Axion quark nuggets (AQN) are hypothetical, macroscopically large objects with a mass greater than a few grams and sub-micrometer size, formed during the quark-hadron transition. Originating from the axion field, they offer a possible resolution of the similarity between visible and dark components of the Universe, i.e. ΩDM∼ Ωvisibleand observed matter-antimatter asymmetry. These composite objects behave as cold dark matter, interacting with ordinary matter and resulting in pervasive electromagnetic radiation throughout the Universe. This work aims to predict the electromagnetic signature in large-scale structures from this AQN-baryon interaction, accounting for thermal and non-thermal radiations. We useMagneticumhydrodynamical simulations to describe the realistic distribution and dynamics of gas and dark matter at cosmological scales. We construct a light cone encompassing a 1.4 square degree area on the sky, extending up to redshiftz= 5.4, and we calculate the electromagnetic signature across a wide range of frequencies from radio, starting atν∼ 1  GHz, up to a few keV X-ray energies. We find that the AQNs electromagnetic signature is characterized by global (monopole) and fluctuation signals. The amplitude of both signals strongly depends on the average nugget mass and the ionization level of the baryonic environment, allowing us to identify a most optimistic scenario and a minimal configuration. The signal of our most optimistic scenario is often near the sensitivity limit of existing instruments, such as FIRAS in theν= [100-500]  GHz range and the South Pole Telescope for high-resolutionℓ> 4000 atν= 95  GHz. Fluctuations in the Extra-galactic Background Light caused by the axion quark nuggets in the most optimistic scenario can also be tested with space-based imagers Euclid and James Webb Space Telescope. In general, our minimal configuration is still out of reach of existing instruments, but future experiments might be able to pose some constraints. We conclude that the axion quark nuggets model represents a viable model for dark matter, which does not violate the canons of cosmology nor existing observations. A reanalysis of existing data sets could provide some evidence of axion quark nuggets if our most optimistic configuration is correct. The best chances for testing the model reside in 1) ultra-deep infrared and optical surveys, 2) future experiments to probe the frequency spectrum of the cosmic microwave background, and 3) low-frequency (1  GHz <ν< 100   GHz) and high-resolution (ℓ≳ 104) observations.
Plasma electron density profile tomography for EAST based on integrated data analysis
Authors: Liu Zijie , Huang Yao , Wu Muquan , Luo Zhengping , Wang Yuehang , Wu Kai , Chen Dalong , Huang Jia , Wang Shouxin , Lian Hui , Zhang Tao , Yuan Qiping , Xiao Bingjia , Li Jiangang ,   the EAST Team
Published: September 2024

Plasma electron density is a crucial parameter in plasma studies. Accurately inverting the plasma electron density profile is vital for plasma control experiments and the investigation of plasma physical mechanisms. This paper proposes an integrated data analysis (IDA) method based on Bayesian inference, which integrates polarimetric interferometry, hydrogen cyanide laser interferometer, and microwave reflectometer diagnostics for inverting the plasma electron density profile. To enhance inversion accuracy, a Gaussian prior probability of the non-stationary hyperparameter is used. This prior probability effectively simulates situations where there is a large plasma electron density gradient in the pedestal, especially under the condition of high-confinement mode discharge. Compared to the use of Gaussian prior probability for the stationary hyperparameter, the proposed IDA method based on the non-stationary hyperparameter prior probability achieves higher inversion accuracy.
How motility affects Ising transitions
Authors: Ray Chandraniva Guha , Mukherjee Indranil , Mohanty P K
Published: September 2024

We study a lattice gas (LG) model of hard-core particles on a square lattice experiencing nearest neighbour attraction J. Each particle has an internal orientation, independent of the others, that point towards one of the four nearest neighbour and it can move to the neighbouring site along that direction with the usual metropolis rate if the target site is vacant. The internal orientation of the particle can also change to any of the other three with a constant rate

ω
.

The dynamics of the model in

ω
→
∞

reduces to that of the LG which exhibits a phase separation transition at particle density

ρ
=

1
2

and temperature

T
=
1
,

when the strength of attraction J crosses a threshold value

ln
⁡
(
1
+

2

)
.

This transition belongs to Ising universality class (IUC). For any finite

ω
>
0
,

the particles can be considered as attractive run-and-tumble particles (RTPs) in two dimensions with motility

ω

−
1

.

We find that RTPs also exhibit a phase separation transition, but the critical interaction required is

J
c

(
ω
)

which increases monotonically with increased motility

ω

−
1

.

It appears that the transition belongs to IUC. Surprisingly, in these models, motility impedes cluster formation process necessitating higher interaction to stabilize microscopic clusters. Moreover, MIPS like phases are not found when J = 0.
Laying the foundations for negative emissions technologies: insights from a workshop
Authors: Shorey Patrick , Arwa Grace Awuor , Schell Kristen R , Abdulla Ahmed
Published: September 2024

Pre-empting the worst consequences of climate change requires both mitigation of emissions from the global energy system and carbon dioxide removal through negative emissions technologies. Despite their nascence, negative emissions technologies are being incorporated into nationally determined contributions to achieve ambitious targets. It is therefore urgent to build a scaffolding that enables their expansion. Here, we report results from a workshop that brought together 34 prominent stakeholders, including scientists, engineers, energy system analysts, economists, experts in public policy, and policy makers. Participants discussed the likely cost and performance of these technologies; elucidated the opportunities and risks facing deployment; and envisioned how nations might build the necessary scaffolding for expansion. The majority narrative is that negative emissions technologies will have a bridging role in decarbonizing existing assets. Different models of deployment were proposed. Reaching the scale of deployment necessary to meet emissions targets is lengthy and expensive. Financial and regulatory risks are seen as greater barriers to deployment at scale than technological risk. Greater certainty regarding carbon pricing, production tax credits, and support for geological characterization and trunkline construction could reduce the former. Critical to expansion is a large-scale increase in low-carbon power production; the implementation of regulatory frameworks that remove uncertainty surrounding investment decisions; and prudent societal engagement.
Highly inhomogeneous interactions between background climate and urban warming across typical local climate zones in heatwave and non-heatwave days
Authors: Kong Jing , Zhao Yongling , Gao Kai , Strebel Dominik , Carmeliet Jan , Lei Chengwang
Published: September 2024

Urban heat island (UHI) in conjunction with heatwave (HW) leads to exacerbation of thermal stress in urban areas. Prior research on UHI and HW has predominantly concentrated on examining the thermal conditions at the surface and near-surface, with few investigations extending to the radiative and dynamical interactions of UHI and HW, particularly with a focus on the inhomogeneities across local climate zones (LCZs). Here, we analyse the temperature disparity between HW and non-HW conditions across LCZs in the Sydney area by quantifying the contributions of individual radiative and dynamical processes using the coupled surface-atmosphere climate feedback-response analysis method (CFRAM). Three moist HW events in 2017, 2019, and 2020 are simulated using the Weather Research and Forecasting (WRF) model coupled with the single-layer urban canopy model (SLUCM). It is found that the maximum surface and 900 hPa temperature difference between HW and non-HW days may reach up to 10 K, with the increased net solar radiation during HWs being comparable to the typical level of anthropogenic heat flux in urban areas. It is also found that the reduction of clouds, the presence of vapour, and the increase of sensible heat contribute to the warming effect to various degrees, with the contribution of clouds being the most dominant. Conversely, the generation of dry convection and the increase of latent heat flux lead to cooling effects, with the latter being more dominant and capable of causing up to 10 K surface temperature difference between LCZ1 (compact high-rise) and LCZ9 (sparsely built). The differences in the contributions of climate feedback processes across different LCZs become more evident during more severe and humid HWs. These findings underscore the necessity of implementing LCZ-tailored heat mitigation strategies.