bluuebunny/crossref_metadata_2025 huggingface dataset:
Bifurcation and stability analysis of within host HIV dynamics with multiple infections and intracellular delay
Authors: Prakash Surya , Umrao Anuj Kumar , Srivastava Prashant K.
Published: January 2025

Human immunodeficiency virus (HIV) manifests multiple infections in CD4+ T cells, by binding its envelope proteins to CD4 receptors. Understanding these biological processes is crucial for effective interventions against HIV/AIDS. Here, we propose a mathematical model that accounts for the multiple infections of CD4+ T cells and an intracellular delay in the dynamics of HIV infection. We study the model system and establish the conditions under which the disease-free equilibrium point and the endemic equilibrium point are locally and globally asymptotically stable. We further provide the conditions under which these equilibrium points undergo forward or backward transcritical bifurcations for the autonomous model and Hopf bifurcation for both the delay model and autonomous models. Our simulation results show that an increase in the rate of multiple infections of CD4+ T cells stabilizes the endemic equilibrium point through Hopf bifurcation. However, in the presence of an intracellular delay, the model system evinces three types of stability scenarios at the endemic equilibrium point—instability switch, stability switch, and stability invariance and is demonstrated using bi-parameter diagrams. One of the novel aspects of this study is exhibiting all these interesting nonlinear dynamical results within a single model incorporating a single time delay.
Low-temperature on-site in situ high-pressure ultrafast pump–probe spectroscopy instrument
Authors: Hasaien Jiazila , Shan P. F. , Zhou F. R. , Zhao Jimin
Published: January 2025

We design and construct an ultrafast optical spectroscopy instrument that integrates both on-site in situ high-pressure technique and low-temperature tuning capability. Conventional related instruments rely on off-site tuning and calibration of the high pressure. Recently, we have developed an on-site in situ technique, which has the advantage of removing repositioning fluctuation. That instrument only works at room temperature, which greatly hampers its application to the investigation of correlated quantum materials. Here, we further integrate low temperature functioning to this instrument, by overcoming enormous technical challenges. We demonstrate on-site in situ high-pressure ultrafast spectroscopy under a tunable temperature, from liquid-helium to above-room temperatures. During the pressure and temperature tuning process, the sample neither moves nor rotates, allowing for reliable systematic pressure- and temperature-dependence data acquisition. Ultrafast dynamics under 10–60 GPa at 130 K, as well as 40–300 K at 15 GPa, is achieved. Increasing and decreasing pressure within 5–40 GPa range at 79 K has also been achieved. The precisions are 0.1 GPa and 0.1 K. Significantly, temperature-induced pressure drifting is overcome by our double-pneumatic membrane technique. Our low temperature on-site in situ system enables precise pressure and temperature control, opening the door for reliable investigation of ultrafast dynamics of excited quantum states, especially phase transitions in correlated materials, driven by both pressure and temperature.
Electronic role of biosemiconductors with C=O bonds
Authors: Fukuhara Mikio , Yokotsuka Tomonori , Samoto Tetsuo , Saito Chika , Fujima Nobuhisa , Hashida Toshiyuki
Published: January 2025

In this study, the electrical conducting properties of six types of biomaterials, comprising cellulose and chitosan derived from terrestrial plants and marine products, respectively, were investigated using electron spin resonance (ESR) and Schottky junction characteristics. Kenaf, chitosan, conifer, and RCH2OH (R = C11H17O9) exhibited ESR spectra showing unpaired electrons at 295 K, demonstrating rectifying effects at room temperature. In contrast, RCOONa (C12H17O11Na) and α-chitin, which did not exhibit observable ESR spectra, showed ohmic conduction behavior. The ESR g value was used to determine the organic radical species, suggesting that electrons originate from the glycosidic C1–O1•–C4 radical in cellulose and the aminyl N•–H radical in chitosan. RCOONa and α-chitin, which possess C=O bonds, suppress electron-induced effects and consequently inhibit the transport of free radicals, resulting in ohmic conduction.
The topology of a chaotic attractor in the Kuramoto–Sivashinsky equation
Authors: Abadie Marie , Beck Pierre , Parker Jeremy P. , Schneider Tobias M.
Published: January 2025

The Birman–Williams theorem gives a connection between the collection of unstable periodic orbits (UPOs) contained within a chaotic attractor and the topology of that attractor, for three-dimensional systems. In certain cases, the fractal dimension of a chaotic attractor in a partial differential equation (PDE) is less than three, even though that attractor is embedded within an infinite-dimensional space. Here, we study the Kuramoto–Sivashinsky PDE at the onset of chaos. We use two different dimensionality-reduction techniques—proper orthogonal decomposition and an autoencoder neural network—to find two different mappings of the chaotic attractor into three dimensions. By finding the image of the attractor’s UPOs in these reduced spaces and examining their linking numbers, we construct templates for the branched manifold, which encodes the topological properties of the attractor. The templates obtained using two different dimensionality reduction methods are equivalent. The organization of the periodic orbits is identical and consistent symbolic sequences for low-period UPOs are derived. While this is not a formal mathematical proof, this agreement is strong evidence that the dimensional reduction is robust, in this case, and that an accurate topological characterization of the chaotic attractor of the chaotic PDE has been achieved.
Resistive flexible pressure sensor based on AgNWs–MXENE sponge for robot skin
Authors: Wang Xiaoli , Liu Shuai , Kang Weidong , Zhang Yanan , Kou Hairong
Published: January 2025

With the rapid development of electronic devices, flexible pressure sensors have been widely used in many fields such as robot skin and wearable devices. However, designing a flexible pressure sensor with high sensitivity, a wide detection range, and easy preparation remains a formidable challenge. In this study, high-elastic sponge is selected as the base material, and silver nanowires (AgNWs) and two-dimensional transition metal carbides (MXENEs) are used as conductive materials. At the same time, AgNWs and PI tape are used as the electrode layer and encapsulation layer, respectively. A resistive flexible pressure sensor based on AgNWs–MXENE sponge is successfully prepared using sandwich encapsulation, and a series of performance tests and practical application tests are carried out on it. The test results show that the sensor has a wide detection range (0–1000 kPa). When the concentration of AgNWs–MXENE is 6%, the sensitivity of the prepared sensor reaches the highest value. Under the pressure of 0–2 kPa, it has a high sensitivity of 0.4901 kPa−1, as well as good response time (100 ms), good stability, and repeatability. It can also accurately detect the tiny and large pressures generated by activities such as pressing, making sounds, swallowing, and bending. This is of great significance for the accurate operation of robots, the functional optimization of wearable devices, and the improvement of the accuracy of health monitoring, and it has broad application prospects in the fields of robot skin, wearable electronic devices, health monitoring, and human–machine interaction.
Robust operation optimization model for building integrated energy system with demand response mechanism and weighting of consumption responsibility
Authors: Zhang Lihui , Cao Qiangnan , Li Songrui
Published: January 2025

The integrated energy systems (IESs) in buildings locally supply energy to users and reduce the different types of energy loss during transmission. IESs are inexpensive and highly reliable. However, IESs must simultaneously meet the demands of multiple load types, consider the thermal inertia of energy transmission, meet user comfort requirements, and manage source and load uncertainties. We established a robust operational optimization model for building IESs considering multiple internal and external factors, such as the integrated demand response mechanism, user comfort, and consumption responsibility weighting. We also introduced information gap decision theory. We simulated and analyzed a demonstration project of a building IES, drawing the following conclusions: (1) The operating cost of the system was 32.66% lower in the system with than without the integrated demand response mechanism. (2) For the thermal inertia of buildings, a larger user comfort index or a larger equivalent thermal resistance led to a smaller user-side heating/cooling load demand. (3) The operating cost was 6.27% lower for the system with than without consumption responsibility weighting. (4) The operating cost of the system using the information gap decision theory to solve the operation optimization model was 10.61% higher than that obtained using the traditional fuzzy chance constraints theory, but the information gap decision theory was more flexible and indicative of operator risk appetite. This study provides guidance for promoting low-carbon operations, the green transformation of building integrated energy systems, and guiding operator energy supply strategies.
Investigations on the performance and wake dynamics of a tidal stream turbine under different yaw-offset conditions
Authors: Ji Renwei , Zheng Jinhai , Xue Mi-an , Sun Ke , Ye Yonglin , Zhu Renqing , Fernandez-Rodriguez E. , Zhang Yuquan
Published: January 2025

The misalignment between flow and rotor can significantly alter the efficiency of the tidal stream turbine (TST), and therefore, it is vital to predict the flow in the tidal field and the performance of the TST under yaw-offset conditions. First, this paper implements a high-precision Lagrangian dynamic sub-grid-scale model based on the large-eddy simulation (LES) method. A classical computational fluid dynamics benchmark case is selected to validate the accuracy of the dynamic LES (DLES) method. The results indicate that the newly implemented dynamic LES method exhibits reduced dissipation and effectively captures the local effects of non-uniform flow fields, including vortex structures. Second, an efficient high-fidelity numerical method (AL-DLES) for forecasting the TST wake is presented by integrating an actuator line (AL) code with the aforementioned DLES method based on the Lagrangian framework. After comparing the experimental results, it was discovered that the newly developed AL-DLES coupling approach, which addresses the issues of challenging turbine meshing, rapid wake dissipation, and insufficient flow field fidelity in previous methods, can accurately simulate the forces acting on the TST while also capturing detailed characteristics of the flow field. Furthermore, the study will be extended to investigate the TST wake dynamics under various yaw-offset conditions, exploring the mechanisms of instability evolution in wake meandering. Meanwhile, the latest third-generation (Ωnew) vortex identification program is implemented and successfully applied to the wake vortex visualization of the TST under yaw-offset conditions. Through a comparative analysis of three distinct vortex identification approaches, it was demonstrated that the Ωnew method exhibits superior accuracy in capturing the vortex system located behind the rotor, eliminating the need for manual threshold selection. In addition, it is capable of simultaneously capturing both strong and weak vortices, which is a vital aspect for future wake research.
Analysis of noise source in a centrifugal pump based on vortex sound theory
Authors: Xu Siyuan , Gong Wuqi
Published: January 2025

Although various structural modifications of the impeller and volute are employed to suppress flow-induced noise, few such modifications focus on the relationship between the generation and the variation of flow and noise. Herein, the spatiotemporal evolution of vortex structure and noise source in impeller and volute is investigated by vortex sound theory and spectral proper orthogonal decomposition (sPOD). The results show that the tip leakage vortex (TLV) formed near the blade leading edge is a significant noise source. As the TLV develops into a passage vortex, the strength of noise source gradually decreases. Within the passage, the noise source at 90% span attenuates because of the interaction between shed vortices, whereas the noise at 50% span is due to the spatial interaction of noise source. Furthermore, the variation of entropy production correlates with noise source. In the near-tongue region, the dominant rotation frequency and second blade passing frequency (2BPF) are obtained by sPOD, which reveals that the jet wake is extracted at 2BPF and flow patterns featuring strip-like structures appear. Correspondingly, the noise source forms a multiscale dotted distribution near the blade trailing edge (BTE). In comparison with original BTE, the wavy BTE effectively suppresses the multiscale pattern of noise source generated from the BTE at rotation frequency and 2BPF, with a decrease in about 20.75% and 8.35% in the total energy of the two leading modes. However, the characteristics of noise source near the tongue remain unchanged. These findings provide meaningful insights into the noise reduction of centrifugal pump.
Prediction of radiation belt relativistic electron phase space density using artificial neural networks
Authors: San Wen , Zou Zhengyang , Yuan Qitong , Hu Jiahui , Zhu Beiqing
Published: January 2025

Relativistic electrons (>1 MeV) saturating Earth's outer radiation belt is widely regarded as a vital risk to human astronomical activities. In the present work, we construct an artificial neural network model to predict the relativistic electron phase space density (PSD) at μ = 1000 MeV/G (the first adiabatic invariant) with K = 0.08 G1/2RE and K = 0.17 G1/2RE (the second adiabatic invariant) at L* (the third adiabatic invariant) ranging from 2.0 to 5.5, based on Van Allen Probe-A observations from 2012 to 2019. The historical values of the solar wind, geomagnetic indices, and the last orbital observations of the electron PSD are all adopted as inputs. Within the core region of relativistic electrons (L* = 3.0–5.5), the model achieves good performance, with overall root mean square errors of 0.1328 and 0.1342, prediction efficiencies of 0.9918 and 0.9916, and Pearson correlation coefficients of 0.9959 and 0.9958 for K = 0.08 G1/2RE and K = 0.17 G1/2RE, respectively. Statistical analysis revealed that 99.9% of the samples present an observation-prediction difference of less than one order of magnitude, 99% present a difference of less than 0.5 order, and 90% present a difference of less than 0.2 order. Furthermore, predictions can accurately reproduce the temporal evolution of the electron PSD during both quiet times and active conditions with no noticeable errors. The current model will aid in further analyzing the competition between the sources and losses of radiation belt particles and contribute to developing a future space weather catastrophe warning system.
A semi-analytical model of multiple multi-stage fractured horizontal well interference with non-uniform simulated reservoir volume in shale gas reservoirs
Authors: Xu Youjie , Meng Zhan , Xiang Zuping , Liang Hongbin
Published: January 2025

The heterogeneous simulation zones will be caused by large-scale horizontal wells volume fracturing. The multiple multi-stage fractured horizontal wells interference has been observed in shale gas reservoirs. The adjacent well production and injection have obvious influence on test well wellbore pressure. The aim of this work is to establish a semi-analytical mathematical model of multiple multi-stage fractured horizontal wells interference with non-uniform simulated reservoir volume. The mathematical model is solved by coupling reservoirs and fracture and sub-zone interface model. This model solution is in agreement with numerical solution, and the calculation efficiency is higher than numerical solution. The result shows that adjacent well production leads to upturned pressure derivative curves and adjacent well injection leads to concave pressure derivative curves. Other vital parameters (such as fracture location, sub-region permeability, and width) have obvious influence on wellbore pressure and derivative curves. This can provide guides for fracturing optimization and optimal carbon dioxide injection rate.
Oscillations of a water droplet on a horizontally vibrating substrate
Authors: Ng King L. , Carnevale Luís H. , Klamka Michał , Deuar Piotr , Bobinski Tomasz , Theodorakis Panagiotis E.
Published: January 2025

Deformed droplets are ubiquitous in various industrial applications, such as inkjet printing, lab-on-a-chip devices, and spray cooling and can fundamentally affect the involved applications both favorably and unfavorably. Here, we employ many-body dissipative particle dynamics to investigate the oscillations of water droplets on a harmonically and horizontally vibrating, solid substrate. Three distinct scenarios of oscillations as a response to the substrate vibrations have been identified. The first scenario reflects a common situation where the droplet can follow the substrate vibrations. In the other two scenarios, favored in the case of hydrophilic substrates, droplet oscillations generate high shear rates that ultimately lead to droplet breakup. Leveraging our simulation model, the properties of the droplet and the mechanisms related to the oscillations are analyzed with a molecular-level resolution, while results are also put in the perspective of experiment. Our study suggests that the three scenarios can be distinguished by the contact-surface velocity of the oscillating droplet, with threshold velocities influenced by the substrate's wettability. Moreover, the mean magnitude of the particle velocity at the contact surface plays a key role in determining the three oscillation phases, suggesting that the capillary number of the oscillating droplet governs the phase behavior. Thus, our approach aims to optimize droplet oscillations and deformations on solid substrates, which have direct implications for technological applications.
Analyzing the effects of internal heating and chemical reactions in a porous layer due to a vertical oblique magnetic field and gravity modulation
Authors: Bixapathi Sapavat , Babu A. Benerji
Published: January 2025

The stability of a vertical oblique magnetic field is investigated both theoretically and numerically, considering the effects of internal heat and chemical reaction under gravity modulation. The experimental setup comprises two opposite plates held at different uniform temperatures and solute concentrations, with the other two plates being permeable. A meticulous stability analysis of a porous medium under the influence of a uniform vertical oblique magnetic field is executed using the Darcy–Lapwood–Brinkman model. For linear stability analysis, normal mode techniques are employed to solve the resulting eigenvalue problem. Subsequently, the critical thermal Rayleigh number, without gravity modulation, is determined for the steady flow regime. The finding results indicate that increasing the magnetic field inclination increases the critical thermal Rayleigh number, signifying increased stability. A nonlinear Ginzburg–Landau equation is derived in the weakly nonlinear analysis using the regular asymptotic perturbation method, based on the assumption of a small modulation amplitude. The effects of gravity modulation on heat and mass transfer are examined through the Nusselt and Sherwood numbers. Additionally, the impact of various parameters on heat and mass transfer is analyzed and presented graphically. The findings show that increasing the Chandrasekhar number decreases the stability of system, thus stabilizing the flow.
Viscous dissipation upon water droplet impact on an oil layer atop water pool
Authors: Lee Donghoon , Kim Ildoo , Lee Jinkee
Published: January 2025

The impact of a droplet onto another liquid is already a complex problem in which many forces are involved, but the problem becomes even more complex when an additional liquid layer is introduced. In this study, we report our investigation of the impact of water droplet on a thin oil layer (∼1 mm) atop water pool. As expected, the oil layer acts as a damper to the impact kinetic energy of the droplet, and the damping is greater as the viscosity of oil increases. We find that the damped energy is associated with the drainage of oil outward from the thin oil layer at the point of impact, i.e., viscous dissipation. To rationalize this observation, we introduce an analytical model that approximates the amount of viscous dissipation based on the volume displacement of oil by impact, defined by the cavity growth rate. Here, we introduce a parameter called the oil layer volume conservation factor and validate the equation indirectly, as the calculated values of this factor fall within the range of experimental values.
Dialogic markers in Ask an Expert webpages on environmental discourse
Authors: Pascual Daniel
Published: January 2025

Scholars and scientists increasingly promote collaboration, accessibility and information sharing through digital
media. One such communicative scenario for scientific dissemination is Ask an Expert practices, where specialised
knowledge of societal relevance is exchanged between expert and non-expert users. Focusing on the discourse of climate change and
environmental sustainability, this paper analyses a corpus of 80 texts from the Ask an Expert webpage of the
MIT Climate Portal by looking into dialogic mechanisms shaping the interaction among users. Insights are
gained into interactional metadiscourse categories, specifically attitude and engagement markers, which characterise experts’
knowledge construction and scientific dissemination in Ask an Expert texts to cater for the needs and
expectations of the general public in the field of environmental sciences.
Quantum curvature fluctuations and the cosmological constant in a single plaquette quantum gravity model
Authors: Blitz Samuel , Majid Shahn
Published: January 2025

Understanding the microscopic behavior of spacetime, in particular quantum uncertainty in the Ricci scalar, is critical for developing a theory of quantum gravity and perhaps solving the cosmological constant problem. To test this, we compute this quantity for a simple but exact discrete quantum gravity model based on a single plaquette of spacetime. Our results confirm initial speculations of Wheeler from 1955 in finding a UV divergence in the quantum uncertainty. We further show that this behavior is stable under renormalization, but potentially unstable with the introduction of a cosmological constant, suggesting that a bare cosmological constant is ruled out.
Study on high-frequency quasi-periodic oscillations in rotating black bounce spacetime
Authors: Yang Shining , Lu Jianbo , Yu Xinping , Xu Jingyang
Published: January 2025

This study investigates the dynamical effects of particles orbiting a celestial body in rotating Simpson-Visser (RSV) spacetime. The results show that, compared to Kerr and rotating regular black holes, the innermost stable circular orbit (ISCO) of an RSV wormhole is closer to the central object. Using high-frequency quasi-periodic oscillation (HFQPO) data from microquasars and $\chi^2$ analysis, we constrain the spin of microquasars and the regularization parameter $l$ in RSV spacetime based on four HFQPO models and their variants, and evaluate the models using the Akaike Information Criterion and Bayes factor. Calculations indicate that $\mathrm{ER}_0$, $\mathrm{ER}_1$, $\mathrm{ER}_2$, $\mathrm{RP}_0$, $\mathrm{RP}_2$, and $\mathrm{WD}$ models have the same support by observational data as the best model $\mathrm{TD}$. Other models considered in this paper have less or no support from observational data. Concretely, for cases of $\mathrm{ER}_0$ and $\mathrm{RP}_0$ models, the observational constraints on RSV regularization parameter are respectively: $l^* = 0.908_{-0.073}^{+0.086}$ and $l^* <0.314$ at $68 \%$ confidence level, which correspond to the regular or the Kerr ($l^*=0$) BH. For $\mathrm{ER}_1$, $\mathrm{ER}_2$, $\mathrm{RP}_2$, $\mathrm{TD}$, and $\mathrm{WD}$ models, the observational data suggest that RSV objects should be the traversable wormhole, e.g. we have the limits: $l^* =1.850 \pm 0.036$, $l^* =4.964 \pm 0.046$, etc.
Magnetically maneuverable micromixer using acoustically excited bubbles
Authors: Chai Lin , Kim Daegeun , Chung Sang Kug , Lee Kang Yong
Published: January 2025

This paper proposes a new type of magnetically actuated micromixer that rotates using acoustically excited bubbles to enhance the mixing performance for not only micro total analysis systems (μTAS) but also targeted drug delivery technologies. The micromixer is capable of being transported to a desired location at various microstructures using magnetic actuation. It can also increase mixing efficiency in viscous environments through minimally invasive process based on acoustically excited bubbles. The micromixer consists of four microtubes containing bubbles and a magnetic liquid metal that can be controlled by magnetic force. High-speed images are used to measure the maximum flow velocity of the microstreaming induced by an acoustically excited bubble in the microtubes of varying lengths and under different acoustic frequencies. When the bubbles of the micromixer are excited acoustically, the micromixer is rotated with microstreaming from the bubbles, and the rotating speed increases as acoustic frequencies approach the bubble’s natural frequency. To investigate the mixing performance, the micromixer mixes a safranin solution in an aqueous medium or a mixture of water and glycerin. The mixing index is then calculated using an image analysis program. The micromixer achieves complete mixing within 40 s, whereas natural diffusion without the micromixer takes considerably longer. The transportation of the micromixer through magnetic actuation is demonstrated and quantified by means of a neodymium magnet placed under a microchannel. As a proof of concept, we experimentally demonstrate the mobility of the proposed micromixer through magnetic actuation and its drug-mixing functionality, which is driven by acoustically excited bubbles in a Y-shaped microchannel.
Bistable liquid shutter operated by DEW actuation for multifunctional miniature cameras
Authors: Park Sanghyun , Chung Sang Kug , Lee Jeongmin
Published: January 2025

To overcome the limitations of conventional mechanical optical elements, liquid-based optical devices such as a lens, prism, iris, and shutter have been proposed and studied since the 2000s. Among these liquid-based devices, various liquid shutter concepts have been presented to attenuate or block incident light in optical switching and imaging systems. To broaden the application of liquid shutters, further exploration of diverse designs optimized from a microfluidic perspective is required to ensure stable performance under vibrational environment. This paper presents a novel bistable liquid shutter operated by dielectrowetting actuation for high-performance and multifunctional camera modules. The opening and closing of the liquid shutter are achieved by controlling the position of an opaque droplet in a microfluidic channel with a dielectrowetting actuator. First, we developed a dielectrowetting actuator for droplet manipulation and a barrier structure for defining a boundary of the manipulation. To achieve bistable operation of where electrical power is only consumed during the opening and closing operations, barrier structures were designed in consideration of Laplace pressure. Second, a liquid shutter device was fabricated through photolithography, thin film deposition, liquid injection, assembly, and packaging. Especially, dry film resists (DFRs) were used to construct the designed barrier structures of various shapes (solid and dotted patterned barriers) and thicknesses (60, 90, and 120 μm) within the microfluidic channel, providing different Laplace pressures. Third, we investigated a liquid crystal as the subject of dielectrowetting actuation and as a light absorber. Next, the response and operational stability of the fabricated liquid shutter device were evaluated by adjusting the design specification, driving signal, and vibrational condition. The proposed liquid shutter features a compact design (∼180 μm in channel height) for miniaturization and operates with low power consumption. These results are expected to contribute to the design of future liquid shutters and similar liquid-based optical devices for multifunctional camera modules with reliable performance.
Study of proton-induced excitation functions on natGe up to 60 MeV
Authors: Anees Ahmed Arshiya , Misiak Ryszard , Mietelski Jerzy W , Brudecki Kamil , Marczewska Barbara
Published: January 2025

The cross sections for the production of medically significant radioisotopes, including 68Ge, 69Ge, 66Ga, 67Ga, 72As and various radioimpurities produced in pure germanium crystal irradiated with 60 MeV protons, were measured. The experiment utilized germanium targets with natural isotopic composition. Irradiation of the targets was performed using a proton beam from the AIC-144 accelerator at the Institute of Nuclear Physics, Polish Academy of Sciences, Krakow. Gamma spectroscopy was conducted with high-purity germanium detectors to measure the gamma-ray emissions from the irradiated targets. This enabled the determination of reaction cross-sections of the produced radionuclides. Additionally, our results were compared with existing literature and TALYS data to validate our findings. Generally, our experimental results align with previous studies, although discrepancies were observed in certain aspects. Specifically, nuclear model calculations and some literature data indicate slightly higher values compared to our findings.
Revisiting airflow resistivity measurement of fibrous porous materials via impedance and transmission loss tubes in the mid-frequency region
Authors: Pandey S , Jena D P
Published: January 2025

Airflow resistivity (AFR) is one of the most significant parameters of any given fibrous porous material for predicting the corresponding acoustical performance. In this experimental research, the AFR is first measured via the ISO 9053 method and then the results are compared with indirect measurements via an impedance tube (IT) and transmission loss (TL) tube following ASTM E1050 and ASTM E2611, respectively. The indirect measurements are carried out up to the duct cut-off frequencies, i.e. 300–4500 Hz, to demonstrate that AFR can be evaluated within an error of

⩽

2.5% even in the mid-frequency (

∼

1–2 kHz) region, superseding the limits of the ultra-low-frequency (2–100 Hz) region as mentioned in the previous literature. From the present experimental studies, it is also revealed that the AFR calculated via IT measurement is somewhat ambiguous since there are periodic peaks and valleys due to the resonance of the air cavity used in the measurement. In contrast, the AFR calculated via the TL tube is even, particularly in the mid-frequency (

∼

1–2 kHz) regime, making it more reliable for AFR estimations.
A parametrization algorithm to compute lower dimensional elliptic tori in Hamiltonian systems
Authors: Caracciolo Chiara , Figueras Jordi-Lluís , Haro Alex
Published: January 2025

We present an algorithm for the construction of lower dimensional elliptic tori in parametric Hamiltonian systems by means of the parametrization method with the tangent and normal frequencies being prescribed. This requires that the Hamiltonian system has as many parameters as the dimension of the normal dynamics, and the algorithm must adjust these parameters. We illustrate the methodology with an implementation of the algorithm computing 2–dimensional elliptic tori in a system of 4 coupled anharmonic oscillators (4 degrees of freedom).
A novel dielectric elastomer with low modulus and fast response
Authors: Wang Qinqin , Shuai Changgeng , Yang Xue , Wu Weibin , Lu Gang
Published: January 2025

Dielectric elastomers (DEs) are highly valued in massive fields of actuators and sensors due to their unique advantages of large actuation strain, fast response speed, high energy density and excellent elasticity. The challenge of balancing the elastic modulus, actuation strain and response speed of DE actuators to stably enhance the actuation performance remains a major issue. In this work, a novel DE was prepared by employing polyurethane acrylate (CN9021) as a crosslinker, n-butyl acrylate as a base monomer and 2-ethylhexyl acrylate (2-EHA) as a functional flexible monomer via a UV curing method. The swelling test indicates a reduction of crosslinking density with the increment of 2-EHA concentration in EHA films. As a consequence, the elastic modulus displays a notable decline while the dielectric constant slightly rises, leading to an enhancement of the actuation sensitivity. More specifically, the elastic modulus of our fabricated EHA-1 is only one-third of the commercial VHB-4910. The developed DEs achieve an actuation strain of nearly 150% with low viscoelasticity and mechanical loss resulting in high response speed and broad operating frequency range to the input dynamic voltages. All these actuation performances are superior to VHB-4910. This work provides a promising strategy for developing DEs with balanced performance and superior actuation characteristics.
Testing the robustness of the BAO determination in the presence of massive neutrinos
Authors: Nadal-Matosas Adriana , Gil-Marín Héctor , Verde Licia
Published: January 2025

We study the robustness of the Baryon Acoustic Oscillation (BAO) feature in the large-scale structure in the presence of massive neutrinos. In the standard BAO analysis pipeline a reference cosmological model is assumed to boost the BAO peak through the so-called reconstruction technique and in the modelling of the BAO feature to extract the cosmological information. State-of-the art spectroscopic BAO measurements, such as the Dark Energy Spectroscopic Instrument claim an aggregate precision of 0.52% on the BAO scale, with a systematic error of 0.1% associated to the assumption of a reference cosmology when measuring and analyzing the BAO feature. While the systematic effect induced by this arbitrary choice of fiducial cosmology has been studied for a wide range of ΛCDM-like models, it has not yet been tested for reference cosmologies with massive neutrinos with the precision afforded by next generation surveys. In this context, we employ the Quijote high-resolution dark-matter simulations with haloes above a mass of M ∼ 2×1013
h
-1
M
⊙, with different values for the total sum of neutrinos masses, ∑mν
[eV] = 0, 0.1, 0,2, 0.4 to study and quantify the impact of the pipeline's built-in assumption of massless neutrinos on the measurement of the BAO signal, with a special focus on the BAO reconstruction technique. We determine that any additional systematic bias introduced by the assumption of massless neutrinos is no greater than 0.1% (0.2%) for the isotropic (anisotropic) measurement. We expect these conclusions also hold for galaxies provided that neutrino properties do not alter the galaxy-halo connection.
Modified Masses and Parallaxes of the Close Visual Triple System HD 2893
Authors: Masda Suhail , Al-Wardat Mashhoor , Aljboor Hussam , Benchi L. R. , Yassin Mariam I. , Aldywailah Reem , Pramod Punnya
Published: January 2025

We present the essential stellar parameters of the close visual triple system HD 2893 using Al-Wardat's method for analyzing binary and multiple star systems in conjunction with Kurucz's model atmospheres. This method accurately computes the spectrophotometric stellar masses through a combined synthetic spectral energy distribution approach that compares the results with observed data. The vigorous approach uses spectroscopic, photometric, and dynamical analysis to yield precise results. The method implements Gaia DR3 measurements and other measurements like those of Hipparcos and 2MASS All-Sky Catalog as a guide for the best fit between the synthetic spectra and observed photometry. The analysis gives precise spectrophotometric stellar masses for the system being

M

Sph

A

=

1.20
±
0.07

M

⊙

,

M

Sph

B

=

1.09
±
0.06

M

⊙

, and

M

Sph

C

=

0.46
±
0.01

M

⊙

. It shows that the three components are main sequence stars with an estimated age of around 1.0 Gyr. When integrated with the dynamical analysis, a new dynamical parallax for the system is obtained, π
dyn = 13.8528 ± 0.20 mas. Additionally, the discussion covers the formation and evolution of the triple system.
Amorphization and siliconization of silicon carbide as a first wall material
Authors: De Aritra , Guterl Jerome , Bergstrom Zachary , Abrams Tyler , Sinclair Gregory , Elder John David , Rudakov Dmitry
Published: January 2025

The understanding and prediction of silicon carbide (SiC) material evolution exposed to SOL plasma conditions is of prime interest because SiC represents a promising main chamber wall plasma-facing material for next-step fusion devices (low hydrogenic diffusion, good mechanical and thermal properties under neutron irradiation). Gross and net Si erosion rates from SiC surfaces in contact with a well-diagnosed L-mode plasma in the DIII-D tokamak have been simulated and the surface concentrations of impurities have been tracked as a function of time. Coupled simulation of surface model and impurity transport demonstrates amorphization of crystalline SiC exposed to L-mode plasma due to the accumulation of displacement damages under ion irradiation. This affects the lifetime of SiC plasma facing components. Surface evolution is tightly coupled to impurity transport in the plasma and therefore needs to be integrated with impurity transport simulations to effectively predict Si erosion rates and sub-surface concentrations as a function of time. The simulation workflow couples a semi-analytical surface model to the impurity transport code GITR. The surface model is a homogeneous mixed-material model that tracks physical & chemical sputtering and reflection of impurities. Gross erosion is primarily influenced by the background plasma parameters and redeposition patterns are mainly influenced by the prompt redeposition due to the gyro-orbits of impurity ions. Although crystalline form of SiC is preferable for fusion wall applications because of resistance to neutron irradiation, this work indicates that crystalline SiC will undergo amorphization under D plasma contact with implications of higher sputtering and fuel retention. These results direct us to explore the effects of amorphization on crystalline SiC and further the physics basis of SiC usage as first wall material for fusion environments.
A construction of random bigraphs and their application to error correction codes*
Authors: Jadav Hareshkumar , Gupta Ashita , Singh Ranveer
Published: January 2025

Recently, it has been shown that almost every (c, d)-bigraph is ‘almost’ Ramanujan. Marcus, Spielman, and Srivastava also demonstrated the existence of infinite sequence of (c, d)-bigraphs that are Ramanujan for all

c
,
d
⩾
3

. In this article, we give a construction of an infinite sequence of random (c, d)-biregular graphs

G
k

,
k
=
1
,
2
,
…
,
∞

, where

G

k
+
1

can be constructed from Gk
in constant time. Experimental results show that they tend to be Ramanujan graphs in very few iterations. Additionally, we use this sequence of random (c, d)-biregular graphs as an error-correcting code proposed by Sipser and Spielman. Experimental results suggest that our graphs, when combined with a bit-flipping algorithm, can successfully correct a significant fraction of errors.
On-detector power distribution for CMS-HGCAL: a busbar-based approach
Authors: Antoszczuk P. , Noy M. , Caregari S. , Almeida J. , Schmidt I. ,   the CMS collaboration
Published: January 2025

An on-detector power distribution scheme for the High Granularity Calorimeter (HGCAL) Phase-2 upgrade of CMS is under development. This scheme is based on a heavy-copper flexible printed circuit board (FPC), allowing for an efficient use of the tight integration space, with minimal insulation overhead, excellent electrical and thermal performance and simplified integration, when compared with a wired solution. This work introduces the technology, how it allows the HGCAL challenges to be overcome, and the characterization studies. Prototypes testing are presented to validate the concept and quantify the manufacturability, electrical performance, and safety of the proposed solution.
Development of a 10-bit ultra-low power SAR ADC with programmable threshold in 130 nm CMOS technology
Authors: Prus Patryk , Firlej Mirosław , Fiutowski Tomasz , Idzik Marek , Moroń Jakub , Świentek Krzysztof
Published: January 2025

The design and simulation results of an ultra-low power, fast 10-bit Successive Approximation Register (SAR) Analog-to-Digital Converter (ADC) in CMOS 130 nm technology are presented. This ADC is an extension of an experimentally verified 10-bit SAR ADC (INL, DNL < 0.5 LSB, ENOB > 9.5), working up to 50 MSps and consuming 680 μW at 40 MSps. The goal of the present work was to add a programmable threshold for the processed input signal, to stop the conversion and thus greatly reduce power consumption in case the signal is below the threshold. The new ADC works up to around 40 MSps and consumes around 350 μW at 40 MSps for low particle occupancy.
Advancement of 3D biofabrication in repairing and regeneration of cartilage defects
Authors: Zheng Zenghui , Yu Dongmei , Wang Haoyu , Wu Hao , Tang Zhen , Wu Qi , Cao Pengfei , Chen Zhiyuan , Huang Hai , Li Xiaokang , Liu Chaozong , Guo Zheng
Published: January 2025

Three-dimensional (3D) bioprinting, an additive manufacturing technology, fabricates biomimetic tissues that possess natural structure and function. It involves precise deposition of bioinks, including cells, and bioactive factors, on basis of computer-aided 3D models. Articular cartilage injuries, a common orthopedic issue. Current repair methods, for instance microfracture procedure (MF), autologous chondrocyte implantation (ACI), and osteochondral autologous transfer surgery have been applied in clinical practice. However, each procedure has inherent limitation. For instance, MF surgery associates with increased subchondral cyst formation and brittle subchondral bone. ACI procedure involves two surgeries, and associate with potential risks infection and delamination of the regenerated cartilage. In addition, chondrocyte implantation’s efficacy depends on the patient’s weight, joint pathology, gender-related histological changes of cartilage, and hormonal influences that affect treatment and prognosis. So far, it is a still a grand challenge for achieving a clinical satisfactory in repairing and regeneration of cartilage defects using conditional strategies. 3D biofabrication provide a potential to fabricate biomimetic articular cartilage construct that has shown promise in specific cartilage repair and regeneration of patients. This review reported the techniques of 3D bioprinting applied for cartilage repair, and analyzed their respective merits and demerits, and limitations in clinical application. A summary of commonly used bioinks has been provided, along with an outlook on the challenges and prospects faced by 3D bioprinting in the application of cartilage tissue repair. It provided an overall review of current development and promising application of 3D biofabrication technology in articular cartilage repair.
New era towards autonomous additive manufacturing: a review of recent trends and future perspectives
Authors: Fan Haolin , Liu Chenshu , Bian Shijie , Ma Changyu , Huang Junlin , Liu Xuan , Doyle Marshall , Lu Thomas , Chow Edward , Chen Lianyi , Fuh Jerry Ying Hsi , Lu Wen Feng , Li Bingbing
Published: January 2025

The additive manufacturing (AM) landscape has significantly transformed in alignment with Industry 4.0 principles, primarily driven by the integration of artificial intelligence (AI) and digital twins (DT). However, current intelligent AM (IAM) systems face limitations such as fragmented AI tool usage and suboptimal human-machine interaction. This paper reviews existing IAM solutions, emphasizing control, monitoring, process autonomy, and end-to-end integration, and identifies key limitations, such as the absence of a high-level controller for global decision-making. To address these gaps, we propose a transition from IAM to autonomous AM, featuring a hierarchical framework with four integrated layers: knowledge, generative solution, operational, and cognitive. In the cognitive layer, AI agents notably enable machines to independently observe, analyze, plan, and execute operations that traditionally require human intervention. These capabilities streamline production processes and expand the possibilities for innovation, particularly in sectors like in-space manufacturing. Additionally, this paper discusses the role of AI in self-optimization and lifelong learning, positing that the future of AM will be characterized by a symbiotic relationship between human expertise and advanced autonomy, fostering a more adaptive, resilient manufacturing ecosystem.
Deep(er) reconstruction of imaging Cherenkov detectors with swin transformers and normalizing flow models
Authors: Fanelli C , Giroux J , Stevens J
Published: January 2025

Imaging Cherenkov detectors are crucial for particle identification (PID) in nuclear and particle physics experiments. Fast reconstruction algorithms are essential for near real-time alignment, calibration, data quality control, and efficient analysis. At the future electron–ion collider (EIC), the ePIC detector will feature a dual Ring Imaging Cherenkov (RICH) detector in the hadron direction, a Detector of Internally Reflected Cherenkov (DIRC) in the barrel, and a proximity focus RICH in the electron direction. This paper focuses on the DIRC detector, which presents complex hit patterns and is also used for PID of pions and kaons in the experiment at JLab. We present Deep(er)RICH, an extension of the seminal DeepRICH work, offering improved and faster PID compared to traditional methods and, for the first time, fast and accurate simulation. This advancement addresses a major bottleneck in Cherenkov detector simulations involving photon tracking through complex optical elements. Our results leverage advancements in Vision Transformers, specifically hierarchical Swin Transformer and normalizing flows. These methods enable direct learning from real data and the reconstruction of complex topologies. We conclude by discussing the implications and future extensions of this work, which can offer capabilities for PID for multiple cutting-edge experiments like the future EIC.