bluuebunny/crossref_metadata_2025 huggingface dataset:
Repartitioning the Hamiltonian in many-body second-order Brillouin–Wigner perturbation theory: Uncovering new size-consistent models
Authors: Dittmer Linus Bjarne , Head-Gordon Martin
Published: February 2025

Second-order Møller–Plesset perturbation theory is well-known as a computationally inexpensive approach to the electron correlation problem that is size-consistent with a size-consistent reference but fails to be regular. On the other hand, the less well-known many-body version of Brillouin–Wigner perturbation theory has the reverse properties: it is regular but fails to be size-consistent when used with the standard MP partitioning. Consequently, its widespread use remains limited. In this work, we analyze the ways in which it is possible to use alternative non-MP partitions of the Hamiltonian to yield variants of BW2 that are size-consistent as well as regular. We show that there is a vast space of such BW2 theories and also show that it is possible to define a repartitioned BW2 theory from the ground state density alone, which regenerates the exact correlation energy. We also provide a general recipe for deriving regular, size-consistent, and size-extensive partitions from physically meaningful components, and we apply the result to small model systems. The scope of these results appears to further set the stage for a revival of BW2 in quantum chemistry.
Effects of outer-layer porous cover sheet parameters on wind loads of double-layer flat roof systems
Authors: Cheng Hao , Shi Ruijie , Chen Bo
Published: February 2025

The double-layer roof system with porous cover sheets (DRSPCS) is widely used in large-scale projects, but existing literature and standards for determining wind loads on the DRSPCS are insufficient. This study conducts wind pressure measurements of the DRSPCS in flat roof buildings with three typical porosities (ϕ = 6.8%, 21.8%, and 36.8%) of the outer-layer porous cover sheets and cavity depths (H = 5, 15, and 25 mm) between the cover sheets and the inner-layer roof by wind tunnel tests. The effects of volume distortion in the scale model, ϕ and H on the wind loads of both outer-layer cover sheets and inner-layer roof are investigated. The results indicate that volume distortion minimally impacts the mean and standard deviation wind pressure coefficients, allowing it to be disregarded in wind tunnel scale model tests for the DRSPCS. Internal pressures within the cavity reduce the mean and peak net wind loads on the outer-layer cover sheets, and increasing H or decreasing ϕ reduces peak wind loads on the inner-layer roof but increases peak net wind loads on the outer-layer cover sheets. In various parameter scenarios of the DRSPCS, the most critical upward wind loads on the outer-layer cover sheets and inner-layer roof are approximately 0.15–0.50 and 0.70–0.95 of those on a single-layer roof with the same dimensions, respectively. Reduction and conversion factors are proposed for estimating wind loads on the DRSPCS based on similar single-layer roofs.
Unlocking high hole mobility in diamond over a wide temperature range via efficient shear strain
Authors: Sun Jianshi , Li Shouhang , Shao Cheng , Tong Zhen , An Meng , Yao Yuhang , Hu Yue , Zhu Xiongfei , Liu Yifan , Wang Renzong , Liu Xiangjun , Frauenheim Thomas
Published: February 2025

As a wide bandgap semiconductor, diamond holds both excellent electrical and thermal properties, making it highly promising in the electrical industry. However, its hole mobility is relatively low and dramatically decreases with increasing temperature, which severely limits further applications. Herein, we proposed that the hole mobility can be efficiently enhanced via slight compressive shear strain along the [100] direction, while the improvement via shear strain along the [111] direction is marginal. This impressive distinction is attributed to the deformation potential and the elastic compliance matrix. The shear strain breaks the symmetry of the crystalline structure and lifts the band degeneracy near the valence band edge, resulting in a significant suppression of interband electron–phonon scattering. Moreover, the hole mobility becomes less temperature-dependent due to the decrease of electron scatterings from high-frequency acoustic phonons. Remarkably, the in-plane hole mobility of diamond is increased by ∼800% at 800 K with a 2% compressive shear strain along the [100] direction. The efficient shear strain strategy can be further extended to other semiconductors with face-centered cubic geometry.
Dynamic drop penetration of vertically oriented fiber arrays
Authors: Rible Gene Patrick S. , Chakpuang Visalsaya , Holihan Aidan D. , Sebek Hannah P. , Osman Hannah H. , Brown Kyle R. , Wang Wei , Dickerson Andrew K.
Published: February 2025

This experimental work investigates the impact dynamics of drops on vertically oriented, three-dimensional-printed (3D-printed) fiber arrays with variations in packing density, fiber arrangement, and wettability. These fiber arrays are inspired by mammalian fur, and while not wholly representative of the entire morphological range of fur, they do reside within its spectrum. We define an aspect ratio, a modified fiber porosity relative to the drop size, that characterizes various impact regimes. Using energy conservation, we derive a model relating drop penetration depth in vertical fibers to the Weber number. In sparse fibers where the Ohnesorge number is less than 4×10−3, penetration depth scales linearly with the impact Weber number. In hydrophobic fibers, density reduces penetration depth when the contact angle is sufficiently high. Hydrophilic arrays have greater penetration than their hydrophobic counterparts due to capillarity, a result that contrasts the drop impact-initiated infiltration of horizontal fibers. Vertical capillary infiltration of the penetrated liquid is observed whenever the Bond number is less than 0.11. For hydrophilic fibers, we predict that higher density will promote drop penetration when the contact angle is sufficiently low. Complete infiltration by the drop is achieved at sufficient times regardless of drop impact velocity.
ABFML: A problem-oriented package for rapidly creating, screening, and optimizing new machine learning force fields
Authors: Geng Xingze , Gu Jianing , Qin Gaowu , Wang Lin-Wang , Meng Xiangying
Published: February 2025

Machine Learning Force Fields (MLFFs) require ongoing improvement and innovation to effectively address challenges across various domains. Developing MLFF models typically involves extensive screening, tuning, and iterative testing. However, existing packages based on a single mature descriptor or model are unsuitable for this process. Therefore, we developed a package named ABFML, based on PyTorch, which aims to promote MLFF innovation by providing developers with a rapid, efficient, and user-friendly tool for constructing, screening, and validating new force field models. Moreover, by leveraging standardized module operations and cutting-edge machine learning frameworks, developers can swiftly establish models. In addition, the platform can seamlessly transition to the graphics processing unit environments, enabling accelerated calculations and large-scale parallel simulations of molecular dynamics. In contrast to traditional from-scratch approaches for MLFF development, ABFML significantly lowers the barriers to developing force field models, thereby expediting innovation and application within the MLFF development domains.
Pressure field estimation of single-phase flows across a tube bundle using physics-informed neural networks
Authors: Rocha Douglas Martins , Lahr Brian Nicholas Alves Rondon , de Souza Leandro Franco , Ribatski Gherhardt
Published: February 2025

This paper presents a methodology for estimating the pressure field from experimental velocity fields using physics-informed neural networks (PINNs). The proposed model estimates pressures directly from raw velocity data, without requiring boundary conditions or regular meshes. Manufactured solutions for a lid-driven cavity problem were employed to evaluate the model's performance, demonstrating reasonable accuracy and minimal dependence on data refinement. Time-averaged vector velocity fields of single-phase flows across a tube bundle, obtained through spatial filter velocimetry, were applied to predict the pressure field from real experimental data. The results confirmed that convective effects dominate the momentum transport equations in tube bundles, and the effects of flow separations became more pronounced as the Reynolds number increases. While inherent uncertainties in the experimental data led to higher deviations compared to the manufactured solutions, data refinement and geometry had a minimal impact on the model's convergence. The proposed method highlights the high versatility of PINNs in pressure field estimation compared to traditional numerical methods, enhancing the extraction of information from experimental data and narrowing the gap between simulations and experiments.
A conceptual generalization of Taylor microscales with applications to isotropic and wall turbulence
Authors: Xiong Wei-Jian , Xu Jinglei , Wang Bing-Chen
Published: February 2025

Two new concepts of the Taylor microscale matrix (TMM) and Taylor microscale tensor (TMT) are proposed to extend the classical concept of Taylor microscale of isotropic turbulence to the general scenario of anisotropic turbulence. The first concept TMM is derived from the classical definition of two-point auto-correlation function, which has shortcomings for not being a tensor. The second concept TMT is proposed based on a new correlation function that rigorously maintains tensor properties. The three eigenvalues of TMM or TMT represent the general Taylor microscales (GTMs). When these three new general concepts, TMM, TMT, and GTM, are applied to homogeneous and isotropic turbulence, the classical Taylor microscale is automatically recovered. The proposed concepts can also be used for characterizing anisotropic turbulence. To demonstrate, direct numerical simulations (DNSs) of turbulent plane-channel flows of three Reynolds numbers are performed. The asymptotic near-wall behaviors of GTM are derived analytically and validated using DNS data. In the current literature, it is popular to study the orientation of turbulent flow structures qualitatively based on the isopleths of a two-point auto-correlation function. As a new advancement, a rigorous explanation of this popular approach is obtained based on the concept of GTM such that the characteristic inclination angle of flow structures (such as the mean angle of hairpin packets) can be precisely defined and computed. It is interesting to observe that in the outer layer, the mean streamwise spacing between two successive hairpin vortices in a hairpin packet is approximately twice the proposed GTM λT1(1).
Large-eddy simulations of Francis turbine flow control by radial jets
Authors: Lutchenko I. I. , Palkin E. V. , Hrebtov M. Yu , Mullyadzhanov R. I. , Alekseenko S. V.
Published: February 2025

Francis turbine operation often experiences part load conditions, at which precessing vortex core (PVC) and double-helix structures can occur, limiting the stable operation range. The study investigates the mitigation of these flow instabilities in a Francis turbine air model by implementing radial jet injection. This approach is based on linear stability analysis and its adjoint formulation, revealing sensitive flow areas. Manipulating these zones can significantly impact instability dynamics. We perform large-eddy simulation of turbulent swirling flow in the Francis turbine model and employ radial injection through 12 circularly distributed holes on the runner crown tip with an injection flow rate of 2% of the inlet flow rate. A comparison with experimental data and a convergence study demonstrated good agreement in velocity fields and pulsation characteristics. Flow control was conducted for a wide range of hole positions and different angles between radial jets and the base flow. Spectral analysis of wall-pressure fluctuations revealed an optimal hole position, coinciding with the experimental results. However, flow control in simulations was less effective, reducing pressure pulsations of azimuthal flow modes m = 0, 1, 2 × 64, 33, and 17%, accordingly. Variation of the jet angle orientation demonstrated the highest pressure variance suppression for 90°. In pressure variance contours, PVC diminishing was observed near the runner crown, but that was amplified downstream.
Thermal drones are highly effective for detecting elusive Bennett’s tree kangaroos (Dendrolagus bennettianus) in Australia’s tropical rainforests
Authors: Norris Emmeline Bernadette Barrett , Larson Johan
Published: February 2025

Tree kangaroos (Dendrolagus spp.) are poorly studied owing to their elusive arboreal nature, which makes detection difficult using traditional methods such as spotlighting and hand-held thermal cameras. This note documents the first successful detection of Bennett’s tree kangaroos (D. bennettianus) using thermal drones in tropical rainforest at Cape Tribulation, Australia. In less than an hour, six individuals were observed across 17 ha. The method proved minimally invasive and highly effective in rainforest environments despite dense vegetation and high temperatures, demonstrating both the unexpected abundance of this species and the utility of thermal drones for monitoring tropical arboreal fauna.
Engineering drive–selection balance for localized population suppression with neutral dynamics
Authors: Willis Katie , Burt Austin
Published: February 2025

While the release of sterile males has been highly successful in suppressing some pest populations, it is impractical for many species due to the males disappearing after a single generation, necessitating large, repeated releases to maintain sufficient impact. Synthetic gene drives promise more efficient approaches since they can increase in frequency from rare, yet this also allows them to spread across a landscape, which may not always be desired. Between these two extremes are selectively neutral genetic constructs which persist at the frequency they are released, offering the potential for efficient suppression that remains localized. One way to achieve this would be to have perfect balance, at all construct frequencies, between gene drive increasing frequency and selection decreasing it. Here, we describe a way to closely approximate this balance using a toxin–antidote genetic construct that causes recessive lethality or sterility, encodes a genomic editor that makes dominant lethal or sterile edits in the genome, and provides protection against the action or consequences of the editing. Computer modeling shows that this design can be 100-fold more efficient than sterile males, increasing to 1,000-fold when released alongside a genetic booster. We describe designs for CRISPR-based molecular construction, including options that avoid using recoded genes as antidotes.
Spatial propagation of temperate phages within and among biofilms
Authors: Winans James B. , Zeng Lanying , Nadell Carey D.
Published: February 2025

Bacteria form groups composed of cells and a secreted polymeric matrix that controls their spatial organization. These groups—termed biofilms—can act as refuges from environmental disturbances and from biotic threats, including phages. Despite the ubiquity of temperate phages and bacterial biofilms, live propagation of temperate phages within biofilms has not been characterized on cellular spatial scales. Here, we leverage several approaches to track temperate phages and distinguish between lytic and lysogenic host infections. We determine that lysogeny within
Escherichia coli
biofilms initially occurs within a predictable region of cell group packing architecture on the biofilm periphery. Because lysogens are generally found on the periphery of large cell groups, where lytic viral infections also reduce local biofilm structural integrity, lysogens are predisposed to disperse into the passing liquid and are overrepresented in downstream biofilms formed from the dispersal pool of the original biofilm-phage system. Comparing our results with those for virulent phages reveals that temperate phages have unique advantages in propagating over long spatial and time scales within and among bacterial biofilms.
A place of their own
Authors: Maia Rita Bueno , Lopes Alexandra
Published: February 2025

This article explores the uses of translation in the production and dissemination of knowledge by Portuguese-speaking exiles in nineteenth-century Paris. The discussion focuses on two key figures: Caetano Lopes de Moura (Bahia, 1780 — Paris, 1860), a Brazilian physician who translated from French into Portuguese historical sources on Brazil available in France, as well as medical and geographical books; and the Viscount of Santarém (Lisbon, 1791 — Paris, 1856), who edited Portuguese-language manuscripts, rewriting them in modern Portuguese, and published works on history, geography, and cartography on Portugal and Lusophone Africa in Portuguese, and self-translated these works into French. Arguably, these translations produced by two very different intellectuals created new forms of scholarship in exile. On the one hand, they changed the landscape of Portuguese scientific language by importing alien concepts and thus creating an experience of foreignisation. On the other hand, the collaborative work involved in translating historical and geographical source texts into (modern) Portuguese led to the formation of a network of displaced intellectuals, thus creating new spaces for translation, the production of knowledge and collaboration.
Mechanisms underlying the distinct K+ dependencies of periodic paralysis
Authors: Foy Brent D. , Dupont Chris , Walker Phillip V. , Denman Kirsten , Engisch Kathrin L. , Rich Mark M.
Published: February 2025

Patients with periodic paralysis have attacks of weakness precipitated by depolarization of muscle. Each form of periodic paralysis is associated with unique changes in serum K+ during attacks of weakness. In hypokalemic periodic paralysis (hypoKPP), the mutation-induced gating pore current causes weakness associated with low serum K+. In hyperkalemic periodic paralysis (hyperKPP), mutations increase a non-inactivating Na+ current (Na persistent or NaP), which causes weakness associated with elevation of extracellular K+. In Andersen–Tawil syndrome, mutations causing loss of Kir channel function cause weakness associated with either low or high K+. We developed a computer model to address two questions: (1) What mechanisms are responsible for the distinct K+ dependencies of muscle depolarization-induced weakness in the three forms of periodic paralysis? (2) Why does extracellular K+ become elevated during attacks of weakness in hyperKPP, reduced in hypoKPP, and both elevated and reduced in Andersen–Tawil syndrome? We experimentally tested the model assumptions about resting potential in normal K+ solution in hyperKPP and hypoKPP. Recreating the distinct K+ dependence of all three forms of periodic paralysis required including the K+ and voltage dependence of current through Kir channels, the extracellular K+ and intracellular Na+ dependence of the Na/K ATPase activity, and the distinct voltage dependencies of the gating pore current and NaP. A key factor determining whether muscle would depolarize was the direction of small net K+ and net Na+ fluxes, which altered ion concentrations over hours. Our findings may aid in development of novel therapy for diseases with dysregulation of muscle excitability.
FAT3 provides a flicker of light
Authors: Short Ben
Published: February 2025

JGP study (Avilés et al. https://doi.org/10.1085/jgp.202413642) reveals that visual perception of high-frequency flickers requires signaling by the tissue polarity protein FAT3 in retinal bipolar cells.
Final report to the CCT on key comparison CCT-K8 - comparison of local realisations of dew-point temperature of humid gas in the range 30 °C to 95 °C
Authors: Gallegos J G , Mitter H , Abe H , Bell S , Benyon R , Carroll P , Choi B I , Deschermeier R , Ebert V , Fernicola V , Wang L , Meyer C , Smorgon D , Vicente T
Published: February 2025

Main text

The report summarises the results of the CCT-K8 key comparison in the field of humidity. The main target of this comparison was to obtain the degree of equivalence (DoE) between realizations of local scales of dew point temperature of humid gas (air), in the range from 30 °C to 95 °C, among the participating national metrology institutes. The report gives details of the scheme, procedure and analysis of the comparison. The overall results display a very good agreement of the nine participating laboratories. The results show excellent agreement between the realized scales with no detected outliers. The performance of the travelling standards was excellent and can be attributed to the intensive preconditioning and selection of the platinum resistance thermometers, prior to their integration into the measuring head assembly, that led to insignificant drift. In the conclusion, some lessons learned are reported that could be beneficial for future key comparisons.

The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the NIST, USA and the BIPM in 60Co gamma radiation
Authors: Kessler C , Burns D , Minniti R
Published: February 2025

Main text

A new key comparison of the standards for air kerma of the National Institute of Standards and Technology (NIST), USA, and the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in October 2023. The comparison result, based on the calibration coefficients for two transfer chambers and expressed as a ratio of the NIST and the BIPM standards for air kerma, is 1.0044 with a combined standard uncertainty of 3.4 parts in 103. The result agrees within the uncertainties with the indirect comparison carried out in 2011, when updated with the changes implemented to the standards at each laboratory. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Aero-engine remaining useful life prediction using a TCN prognostic model enhanced with dual-dimensional fusion attention
Authors: Xiong Yuxing , Guo Bin , Dian Songyi
Published: February 2025

Remaining useful life (RUL) prediction is an essential technique in the prognostics and health management of aero-engines, crucial for ensuring reliability and safety. Recently, data-driven methods have achieved notable progress in aero-engine RUL prediction. However, they often neglect the impact of dimensional information and the coupling information between dimensions, failing to meet the requirements of long-term prediction tasks for aero-engines. This paper presents a prognostic model for aero-engine RUL prediction, utilizing a temporal convolutional network (TCN) enhanced by dual-dimensional fusion attention to tackle these challenges. Initially, the feature attention module is employed to weight the data from various engine sensors, thereby emphasizing key features. Subsequently, the TCN learns the temporal dependencies from the weighted input data. Additionally, a dual-dimension fusion attention module is designed to account for interactions between different dimensional data of the engine. This module extracts features from various sensors and time steps through parallel sub-structures and captures the coupling information between dimensions using an attention fusion unit, achieving inter-dimensional correlation of aero-engine data. Finally, the proposed model’s effectiveness was verified using the widely recognized C-MAPSS dataset. The results demonstrate that it outperforms state-of-the-art methods in aero-engine RUL prediction accuracy, confirming its superiority.
Silicon nanowire-based ammonia gas sensor with enhanced response at elevated humidity levels
Authors: Sultan M T , Fakhri E , Powroznik P , Manolescu A , Jakubik W , Kazmierczak-Balata A , Svavarsson H G
Published: February 2025

Ammonia (NH3) is a corrosive and toxic gas to which exposure can cause serious health problems and even death. Elevated levels of it in exhaled breath can serve as a biomarker for various diseases. Consequently, monitoring NH3 in the ambient air and for medical diagnostics is important for public health and safety. However, developing NH3 gas sensors that function effectively in high humidity conditions, such as those found in human breath, has proven challenging. In this study, we present a simple and cost-effective NH3 gas-sensor based on a structure of interconnected silicon nanwires (SiNWs), fabricated with metal-assisted chemical etching. Two different versions were made and compared; SiNWs, with and without germanium nanoparticles. The sensing mechanism is attributed to the formation of a hole accumulation layer in the air, whose width decreases upon exposure to NH3. It was also observed that bundling of individual nanowires enhances the sensor’s response time, down to approximately 70 s, which is an order of magnitude faster response than that of similar SiNW structures reported in the literature.
Ultra-fast terahertz optical switch based on metal vanadium dioxide
Authors: Zhu Jun , Pan Zhe , Xiong Jiayuan , Wu Xuehua
Published: February 2025

The performance of optical switches in optical systems is often constrained by the material’s limited response speed and tunable range. In this study, we propose a novel terahertz optical switch based on vanadium dioxide (VO2) to address these challenges. The switch is composed of a VO2 layer, a dielectric spacer, and a gold plasmonic film. The ultrafast insulator-to-metal phase transition of the VO2 layer facilitates precise modulation of the coupling between surface plasmon modes and incident electromagnetic waves. Through comprehensive time-domain and frequency-domain analyses, the ultrafast response time of VO2 was experimentally validated. The results demonstrate near-perfect absorption (99.99%) and an exceptionally high modulation depth of absorption efficiency (99.92%) during the phase transition. Furthermore, the reflectivity of the switch dramatically changes from −0.38 dB to −23.3 dB, achieving a switching ratio of 22.92 dB. These findings highlight the potential of VO2-based optical switches for advanced terahertz optical communication and signal processing applications.
Uncertainty quantification of a collisional-radiative model for hydrogen plasmas
Authors: Bruno Domenico
Published: February 2025

A collisional-radiative model for the Balmer emission from low-temperature Hydrogen plasma is studied. The model is based on the most accurate cross sections available for the relevant processes. An uncertainty quantification study based on Polynomial Chaos expansion is performed for ionizing and recombining plasmas with conditions typical of the tandem discharge used in Neutral Beam sources for magnetically confined fusion reactors. Results show that uncertainties in the model results larger than a factor of 5 are obtained, much larger than the typical uncertainty in the measurements. The approach, however, allows to identify few processes that have the largest role in propagating the uncertainties and where increased accuracy has the largest impact.
Refractive-index sensing based on terahertz cavity-modal confinement of Bragg metal grating structure
Authors: You Borwen , Hsieh Che-Chu , Lin Yen-Shan , Lu Pin-Jung , Tsai Hung-Yi , Yu Liang-Cheng , Chang Shiun-Yun , Wu Yuan-Chi , Liang Zhe-Quan
Published: February 2025

Integrated sensing platforms, which possess active layers of local electric-field oscillation in the terahertz (THz) frequency, can sensitively detect analytes via electromagnetic (EM) wave guidance, resonance, and spatial confinement in the system of THz time-domain spectroscopy. A Bragg grating structure of periodically perforated metal slits (PPMSs) is presented here as an active layer to generate the local electric-field oscillation of metal-cavity EM wave resonance that is coupled from 0.1–1 THz metal surface waves along the wavelength-scaled segments of metal slabs. The cavity modal confinement property, which is characterized from device transmittance or loss spectra, leads to the distribution of the metal-cavity wave resonance over a 35-pitch length and a 0.1–0.2 mm metal thickness of PPMSs. These two distribution dimensions of metal-cavity wave resonance represent longitudinal and transverse confinement performances, respectively. The PPMS-THz waves specified by 2D spatial confinement can realize the functional integration of a dielectric superstrate component and a sample adsorbing layer to adjust the dispersion responsivity and concentration of analytes, respectively. A refractive-index sensing application of glucose is presented by this integrated scheme for a molecular density range of 0–24 μg mm−2 and a resolution density of 1.6 μg mm−2. The PPMS-based THz integrated sensing platform facilitates the developments of specific test papers and relevant molecular surface modification to target molecules.
Gravitational Faraday-Cartan effect beyond gravitomagnetism due to dark matter intrinsic spin
Authors: Barriga Francisco , Izaurieta Fernando , Lepe Samuel , Meza Paola , Muñoz Jethzael , Quinzacara Cristian , Valdivia Omar
Published: February 2025

We show that the spin of dark matter induces a gravitational analog of the electromagnetic Faraday effect, where the polarization of gravitational waves undergoes a rotation as they propagate through a dark matter halo with a non-vanishing axial hypermomentum. An expression for the gravitational rotation angle is provided, which is analogous to the Faraday rotation in optics, and evaluate its significance in astrophysical settings. Although the effect is expected to be small under current observational constraints, we discuss its potential importance in the early universe.

Importantly, this effect is distinct from the known gravitational Faraday rotation in gravitomagnetism, where the geometry of general relativity is split into a background and a low-frequency gravitomagnetic perturbation. In that framework, the polarization of an electromagnetic wave (or a high-frequency GW perturbation) rotates relative to the background geometry. In contrast, this gravitational Faraday-Cartan effect arises from a non-vanishing dark matter axial hypermomentum that breaks the parallel transport of GW polarization, without invoking any gravitomagnetic approximation. Notably, it only rotates gravitational wave polarization without affecting the electromagnetic wave one.
Electrochemical control of photoelectric performance in WS2/WSe2 van der Waals heterostructures device
Authors: Wang Linghan , Wang Qinsheng
Published: February 2025

Electrochemical intercalation is an effective method for modulating the physical properties of materials, extensively utilized in optimizing device performance in two-dimensional materials. However, research about the modulation on the optoelectronic performance is still lacking. Here, we demonstrate using lithium-ion intercalation to modulate the optoelectronic performance of WS2/WSe2 heterojunction. We observe a significant increase of device conductivity (approximately 50x) after lithium-ion intercalation. At the same time, the peak responsivity increases by 8 times and can be modulated from 8 mA/W to -6 mA/W, accompanied with a reversal of photocurrent direction. No phase transitions are observed throughout the intercalation process by Raman spectroscopy. The variations in photocurrent response are attributed to the injection of free charge carriers and the corresponding alterations in the band structure. Our work paves the way for modulating the optoelectronic performance of two-dimensional materials with electrochemical intercalation.
Enhanced energy storage properties of lead-free BNT-based ceramics by introducing Na0.7La0.1NbO3
Authors: Wang H , Li E Z
Published: February 2025

High energy density ceramic materials play an important role in pulse systems. In this study, (1-x)(0.70Bi0.5Na0.5TiO3-0.30BiFeO3)-xNa0.7La0.1NbO3 (x = 0, 0.08, 0.16, and 0.24) (BNT-BFO-xNLN) ceramics were prepared using the traditional solid-state method. The crystal structure, microstructure, ferroelectricity, dielectric properties, energy storage density, and pulse charge-discharge performance of BNT-BFO-xNLN ceramics were systematically investigated. All BNT-BFO-xNLN ceramics exhibited a pure perovskite structure, indicating the successful incorporation of NLN into the BNT-BFO lattice. With the introduction of NLN, the P-E hysteresis loops of BNT-BFO ceramics gradually transformed from a saturated state to a slender state due to the relaxation dielectric peak shifting to room temperature. BNT-BFO-0.16NLN ceramics revealed superior energy storage properties (W
rec = 4.17 J/cm3, η = 79.2%) under an electric field of 300 kV/cm. Additionally, BNT-BFO-0.16NLN ceramic exhibited a current density (C
D) of 164.0 A/cm2 and a power density (P
D) of 13.1 MW/cm3, making it a potential material for pulse system energy storage.
Numerical simulation of 50mm thick Q420 steel plate welding with multi-layer and multi-pass welding process
Authors: Sun Xuejun , Yao Jianzhong , Mao Congbing , Wei Jiacheng
Published: February 2025

This study uses finite element software to simulate and analyze a multi-layer, multi-pass (seven layers and twenty-two passes) welding technique applied to V-groove butt weld for 50mm thick Q420 steel plates. The simulation accurately depicts the temperature distribution during the welding process using a double ellipsoid heat source model. Temperatures gradually increase along each weld pass trajectory until reaching peak values exceeding 2000°C at specific points, while the underlying base metal reaches temperatures as high as 300°C. By examining metallic phases’ spatial allocation and compositional characteristics alongside thermal distribution after extensive welding simulations, these findings provide valuable insights for optimizing multi-layer, multi-pass welding procedures related to Q420 steel plates.
Synthesis and properties of non-phosphorus and nitrogen-free epoxy succinic acid copolymer
Authors: Yan M F , Liu Z , Li H H , Gao Y H , Liu Z F
Published: February 2025

A ternary polymer was synthesized from, itaconic acid (IA), hydroxyethylene acrylate (HEA) and epoxysuccinic acid (ESA). The optimal synthesis conditions were screened based on dispersion property and scale inhibition performance evaluations. The scale inhibition efficiency was evaluated using static methods, and the performance of dispersing was evaluated by testing the dispersion of Fe2O3. The results suggested that with a molar proportion of reaction raw materials (ESA/IA/HEA) of 3:3:1, an initiator dosage of 5%, polymerization temperature of 90°C, and polymerization time of 4 h, the polymer had the greatest dispersion property and scale inhibition performance. A biodegradability results showed that, on the 28th day, the biodegradation rate reached 78.5%. The ternary polymer was a phosphorus-free and non-nitrogen agent. The polymer provided great scale inhibition and dispersion performance with good biodegradability.
New alternative equivalent phantom materials developed for radiotherapy applications
Authors: Samson D O , Zuber S H , Shukri A , Aziz M Z A , Biodun A D , Fadzil M S A , Yahya N A , Buba A D A
Published: February 2025

This paper reported an eco-friendly natural-based composite phantom equivalent to human body tissues prepared by mangrove wood, soy proteins, sodium hydroxide, and three different amounts of itaconic acid polyamidoamine-epichlorohydrin. The probability of photon interactions was comprehensively analyzed using Monte Carlo code EGSnrc PEGS4 simulation in the 0.001-70.0 MeV range and compared with those of water and solid water phantoms. The results showed that the obtained radiation attenuation factors had similar parameters to those of water and other commercially available equivalent materials with χ
2 values (DSF15:SPC15:SPI15 = 0.064:0.099:0.075). Moreover, for the fractional probability of photon interactions computations, no significant difference for Compton scattering interaction was observed for water and solid water phantoms in the selected energies range, demonstrating the consistency of the constructed phantoms. Development of mangrove wood-based tissue equivalent materials under the conditions (DSF/SPC/SPI/NaOH/IA-PAE = 3.0:3.0:1.2:1.0:1.5, 150 kgcm−2, 180°C, 18 min) could be conducive as potential application in radiotherapy.
Reliability tests of the SFP+ transceivers and the TGC readout board for the ATLAS experiment at HL-LHC
Authors: Hashimoto D. , Horii Y. , Ishino M. , Kondo S. , Kurashige H. , Maeda J. , Maeno R. , Makita A. , Morimoto H. , Nagasaka R. , Narukawa Y. , Ohsumi Y. , Okumura Y. , Tomoto M. , Wada A.
Published: February 2025

Results are presented for reliability tests of the SFP+ transceivers and the readout board of Thin Gap Chambers (TGC) for the ATLAS experiment at HL-LHC. The radiation tolerance was evaluated for the SFP+ transceivers from Broadcom and FS and the TGC frontend board with gamma ray irradiation up to 𝒪(100) Gy at the Cobalt-60 facility of Nagoya University. An accelerated aging test was also performed for the SFP+ transceivers with the Kintex-7 evaluation board integrated in the temperature chamber.
Reusable verification components for High-Energy Physics readout ASICs
Authors: Lupi M. , Esposito S. , Llopart-Cudie X. , Pulli A. , Scarfì S. , Kharwadkar N.
Published: February 2025

Verification is a critical aspect of designing front-end (FE) readout ASICs for
High-Energy Physics (HEP) experiments. These ASICs share several similar functional features,
resulting in similar verification objectives, which can be addressed using comparable verification
strategies. This contribution presents a set of re-usable verification components for addressing
common verification tasks, such as clock generation, reset handling, configuration, as well as hit
and fault injections. The components were developed as part of the CHIPS initiative and they have
been successfully used in the verification of multiple HEP ASICs.
Triple GEM detectors for the Phase-2 upgrade of the CMS experiment at the LHC
Authors: Buonsante M. , Pellecchia A. , Radogna R. ,   the CMS collaboration
Published: February 2025

The High-Luminosity LHC (HL-LHC) will increase proton-proton collision rates to 5–7.5 times the nominal LHC luminosity, with an expected number of 140–200 pp-interactions per bunch crossing (Pile-up or PU). To maintain the performance of muon triggering and reconstruction under high background, the forward part of the Muon spectrometer of the CMS experiment will be upgraded with Gas Electron Multiplier (GEM) and improved Resistive Plate Chamber (iRPC) detectors. A first GEM station (GE1/1) was installed during Long Shutdown 2 (LS2, 2019–2021) while second and third stations (GE2/1 and ME0) will be installed in the third Long Shutdown (LS3, 2026–2028) and during the Run 4 technical stops. GE1/1, considered an early Phase-2 upgrade, will reduce the p
T
threshold by combining GEM and Cathode Strip Chamber (CSC) hits in the forward muon system at twice the LHC design luminosity (2 × 1034/cm2 s, 50 PU). The commissioning of the GE1/1 detector has been completed during Run 3 in 2022 and 2023. Most chambers are operating stably with an efficiency higher than 95%. Demonstration of the combined CSC-GEM trigger will take place in 2024. The first GE2/1 detectors were installed in the LHC 2023–24 technical stop and the ME0 detector is entering the production phase in 2024. This presentation discusses the commissioning and early performance of GE1/1, together with the lessons learnt which were used to improve the detector and electronics design for GE2/1 and ME0. We also present the R&D performed to optimize the ME0 detector for its high-rate environment, together with the performance measurements of the first stack of ME0 detectors for standalone muon segment reconstruction.
Expert projections on the development and application of bioenergy with carbon capture and storage technologies
Authors: Heimann Tobias , Wähling Lara-Sophie , Honkomp Tomke , Delzeit Ruth , Pirrone Alessandra , Schier Franziska , Weimar Holger
Published: February 2025

Bioenergy with carbon capture and storage (BECCS) is a crucial element in most modelling studies on emission pathways of the Intergovernmental Panel on Climate Change to limit global warming. BECCS can substitute fossil fuels in energy production and reduce CO2 emissions, while using biomass for energy production can have feedback effects on land use, agricultural and forest products markets, as well as biodiversity and water resources. To assess the former pros and cons of BECCS deployment, interdisciplinary model approaches require detailed estimates of technological information related to BECCS production technologies. Current estimates of the cost structure and capture potential of BECCS vary widely due to the absence of large-scale production. To obtain more precise estimates, a global online expert survey (N = 32) was conducted including questions on the regional development potential and biomass use of BECCS, as well as the future operating costs, capture potential, and scalability in different application sectors. In general, the experts consider the implementation of BECCS in Europe and North America to be very promising and regard BECCS application in the liquid biofuel industry and thermal power generation as very likely. The results show significant differences depending on whether the experts work in the Global North or the Global South. Thus, the findings underline the importance of including experts from the Global South in discussions on carbon dioxide removal methods. Regarding technical estimates, the operating costs of BECCS in thermal power generation were estimated in the range of 100–200 USD/tCO2, while the CO2 capture potential was estimated to be 50–200 MtCO2yr−1 by 2030, with cost-efficiency gains of 20% by 2050 due to technological progress. Whereas the individuals’ experts provided more precise estimates, the overall distribution of estimates reflected the wide range of estimates found in the literature. For the cost shares within BECCS, it was difficult to obtain consistent estimates. However, due to very few current alternative estimates, the results are an important step for modelling the production sector of BECCS in interdisciplinary models that analyse cross-dimensional trade-offs and long-term sustainability.
Shorter growing seasons may moderate climate change effects on crop water demands
Authors: Abatzoglou John T , Parker Lauren E , Viers Joshua H , Medellín-Azuara Josue , Escriva-Bou Alvar , Huntington Justin L , Williams Emily L , Rajagopalan Kitri
Published: February 2025

Rising evaporative demand (ETo) with a warming climate contributes to diminished water availability in water-stressed agricultural regions globally. While increased ETo typically necessitates increased irrigation, we explore how crop phenological response can moderate this challenge. Focusing on five key agricultural crops in California’s San Joaquin Valley (SJV), we employ coupled water balance and phenology models to project crop water demands as a function of increased ETo and changing phenology. All crops exhibited accelerated growth from a shortened growing season with warming. The shortened crop maturation period partially to fully offset increased crop water demands due to rising ETo, with the largest phenological influence for annual crops such as tomato and corn. By contrast, models that do not account for phenological changes showed increased irrigation demands of approximately 3.5%–4.5% per °C of global warming primarily due to increased ETo. Integration with dynamic phenological models for the five key crops across the extent of agricultural land in the SJV showed a 1.6% decrease in irrigation needs under a 2 °C warming scenario. While phenological change alongside plant physiological responses to increased atmospheric CO2 may help buffer the impact of climate change on crop irrigation demand, decreased crop yields with a shorter growing season and continued reliance of groundwater reserves for agricultural water use and reduced spring snowpack will threaten coupled agricultural and water security in the region.
A novel approach to rapidly tracking whole-farm methane emissions
Authors: Chen Huilin , Vinković Katarina , Sun Chu , Peters Wouter , Hensen Arjan , van der Gon Hugo Denier , van Zanten Margreet , van den Bulk Pim , Velzeboer Ilona , van der Zee Tim
Published: February 2025

Enteric fermentation and manure from livestock farming are major sources of methane (CH4) emissions and have a large potential for emissions reduction. However, there is a lack of effective methods for evaluating future emissions reduction efforts, especially at the farm scale. We developed a rapid analysis method to evaluate CH4 emissions from a large number of dairy cow farms in the Netherlands based on single-transect mobile van measurements of CH4 concentrations downwind of farms located between 80 and 750 m from the road. Methane emissions from 51 dairy cow farms were determined on four campaign days within a total of 7 measurement hours between November 2017 and November 2018 using an inverse Gaussian approach combined with two different wind datasets and their composite. We found a range of moderate to high correlation (R
2: minimum 0.42, maximum 0.86) between the estimated CH4 emission rates for 11–16 farms on each measurement day and the number of animal units (AUs, 1 AU equals 500 kg of animal weight) across four individual days. The whole-farm CH4 emission factors (including both enteric fermentation and manure) for the four separate campaign days were estimated using the slope between the CH4 emission rates derived from the composite of two distinct wind datasets and the number of AUs. Daily emission factors for the four campaign days were estimated to be in the range of 0.18–0.50 kgCH4/d/AU. From the dataset, averaged over each of the four campaign days, we derived an estimate of the whole-farm CH4 emission factor, with a 95% confidence interval of 0.47 [0.13–0.81] kgCH4/d/AU. Our results demonstrate that CH4 emissions from a large number of dairy cow farms can be rapidly estimated, providing an independent way to evaluate country-specific emission factors and a potential way to monitor future emission reductions.