bluuebunny/crossref_metadata_2025 huggingface dataset:
(C6H15N3)1.3(NH4)1.5H1.5In3SnS8: a layered metal sulfide based on supertetrahedral T2 clusters with photoelectric response and ion exchange properties
Authors: Yang Lu , Wen Xin , Yang Tian , Hu Qian-Qian , Liu Jia-Ting , Yin Hai-Yan , Ablez Abdusalam , Feng Mei-Ling , Huang Xiao-Ying
Published: March 2024

A new layered metal sulfide composed of interlinking supertetrahedral T2 clusters as secondary building units is synthesized and structurally studied, which shows photoelectric response and ion exchange properties after activation.
Enhancing capacitive deionization for water desalination: the role of activated carbon in contaminant removal
Authors: Wang Xuan , Shan Shuya , Zhang Yaoli , Shi Sheldon Q. , Xia Changlei
Published: March 2024

The desalination of saline water is of great importance in water-stressed areas.
Solvent-modulated assembly of peptide and cerium functionalized gigantic {Mo120Ce6}2 dimers for high-efficiency photocatalytic oxidation
Authors: Zhou Dexiang , Li Bingbing , Zhao Qixin , Tang Xinyu , Lan Tingya , Su Heyang , Yang Guoping , Xuan Weimin
Published: March 2024

Two gigantic peptide and cerium functionalized {Mo120Ce6}2 dimers have been constructed via a solvent-modulated assembly and applied for effective photocatalytic aerobic oxidation of sulfides to sulfoxides.
An integrated carbonized wood-based gas-diffusion electrode for high-current-density CO electrosynthesis in flow cells
Authors: Tao Huanhuan , Chang Huaiyu , Wang Fang , Zhang Zhengguo , Min Shixiong
Published: March 2024

An integrated carbonized wood-based gas-diffusion electrode embedded with reconstructed Ag nanoparticles is developed, exhibiting activity and selectivity towards the CO2RR.
Construction of brick/mortar-like graphene/thermoset composites with highly anisotropic thermal conductivity and strong electromagnetic interference shielding performance
Authors: Yao Zhenhao , Song Jianan , Lu Yin , Yang Rui , Zhang Yuan , Zhang Kan
Published: March 2024

A new fabricating strategy has been successfully employed to prepare brick/mortar-like graphene/thermoset composites with highly anisotropic thermal conductivity and excellent electromagnetic interference shielding performance.
Modulated spontaneous and stimulated emission in luminescent films using one-dimensional photonic crystal filters
Authors: Guo Xu , Zou Deyue , Guo Xiaoyang , Lv Ying , Wang Tienan , Wang Yunjun , Liu Xingyuan
Published: March 2024

Spontaneous and stimulated emission properties of luminescent films can be modulated by the intrinsic defect mode of one-dimensional photonic crystals (1DPCs) filters when separating the defect layer from the luminescent layer.
In situ transmission electron microscopy (TEM) study on the structural evolution behavior of nano Sn sheets under a thermal field
Authors: Zhou Xia , Zhang Junwei , Li Hongli , Ma Cong , Zhao Yiqun , Zhang Hong , Peng Yong
Published: March 2024

The pure Sn nanosheets were produced into nanospheres under the action of in-situ thermal field, and a heating experiment conducted on Sn and Cu interface samples, thereby elucidating the limitation of pure Sn as a solder material.
TeV pion bumps in the gamma-ray spectra of flaring blazars
Authors: Petropoulou M. , Mastichiadis A. , Vasilopoulos G. , Paneque D. , Becerra González J. , Zanias F.
Published: March 2024

Context.Very high-energy (VHE,E > 100 GeV) observations of the blazar Mrk 501 with MAGIC in 2014 provided evidence for an unusual narrow spectral feature at about 3 TeV during an extreme X-ray flaring activity. The one-zone synchrotron-self Compton scenario, widely used in blazar broadband spectral modeling, fails to explain the narrow TeV component.

Aims.Motivated by this rare observation, we propose an alternative model for the production of narrow features in the VHE spectra of flaring blazars. These spectral features may result from the decay of neutral pions (π0bumps) that are in turn produced via interactions of protons (of tens of TeV energy) with energetic photons, whose density increases during hard X-ray flares.

Methods.We explored the conditions needed for the emergence of narrowπ0bumps in VHE blazar spectra during X-ray flares reaching synchrotron energies ∼100 keV using time-dependent radiative transfer calculations. We focused on high-synchrotron peaked (HSP) blazars, which comprise the majority of VHE-detected extragalactic sources.

Results.We find that synchrotron-dominated flares with peak energies ≳100 keV can be ideal periods for the search ofπ0bumps in the VHE spectra of HSP blazars. The flaring region is optically thin to photopion production, its energy content is dominated by the relativistic proton population, and the inferred jet power is highly super-Eddington. Application of the model to the spectral energy distribution of Mrk 501 on MJD 56857.98 shows that the VHE spectrum of the flare is described well by the sum of a synchrotron self-Compton (SSC) component and a distinctπ0bump centered at 3 TeV. Spectral fitting of simulated SSC+π0spectra for the Cherenkov Telescope Array (CTA) show that aπ0bump could be detected at a 5σsignificance level with a 30-min exposure.

Conclusions.A harder VHEγ-ray spectrum than the usual SSC prediction or, more occasionally, a distinct narrow bump at VHE energies during hard X-ray flares, can be suggestive of a relativistic hadronic component in blazar jets that otherwise would remain hidden. The production of narrow features or spectral hardenings due toπ0decay in the VHE spectra of blazars is testable with the advent of CTA.
ARTPOL: Analytical ray-tracing method for spectro-polarimetric properties of accretion disks around Kerr black holes
Authors: Loktev Vladislav , Veledina Alexandra , Poutanen Juri , Nättilä Joonas , Suleimanov Valery F.
Published: March 2024

Spectro-polarimetric signatures of accretion disks in X-ray binaries and active galactic nuclei contain information on the masses and spins of their central black holes, as well as the geometry of matter in proximity to the compact objects. This information can be extracted by means of X-ray polarimetry. In this work, we present a fast analytical ray-tracing technique for polarized light (ARTPOL) that helps us to obtain the spinning black hole parameters from the observed properties. This technique can replace the otherwise time-consuming numerical ray-tracing calculations for any optically thick or geometrically thin accretion flow. For the purposes of illustration, we considered a standard optically thick, geometrically thin accretion disk in the equatorial plane of the Kerr black hole. We show that ARTPOL proves accurate for dimensionless spin parameter a ≤ 0.94 with a speed that is over four orders of magnitude faster than direct ray-tracing calculations. This approach opens up broader prospects for direct fittings of the spectro-polarimetric data from the Imaging X-ray Polarimetry Explorer.
Cyclotron line formation in the radiative shock of an accreting magnetized neutron star
Authors: Loudas Nick , Kylafis Nikolaos D. , Trümper Joachim
Published: March 2024

Context. Magnetic neutron stars (NSs) often exhibit a cyclotron resonant scattering feature (CRSF) in their X-ray spectra. Accretion onto their magnetic poles is responsible for the emergence of X-rays, but the site of the CRSF formation is still a puzzle. A promising candidate for high-luminosity sources has always been the radiative shock in the accretion column. Nevertheless, no quantitative calculations of spectral formation at the radiative shock have been performed so far.

Aims. It is well accepted that, in the accretion column of a high-luminosity, accreting magnetic NS, a radiative shock is formed. Here, we aim to explore the scenario where the shock is the site of the cyclotron-line formation. We studied spectral formation at the radiative shock and the emergent spectral shape across a wide range of the parameter space and determined which parameters hold an important role in shaping a prominent CRSF.

Methods. We developed a Monte Carlo (MC) code based on the forced first collision numerical scheme to conduct radiation transfer simulations at the radiative shock. The seed photons were due to bremsstrahlung and were emitted in the post-shock region. We properly treated bulk-motion Comptonization in the pre-shock region, thermal Comptonization in the post-shock region, and resonant Compton scattering in both regions. We adopted a fully relativistic scheme for the interaction between radiation and electrons, employing an appropriate polarization-averaged differential cross-section. As a result, we calculated the angle- and energy-dependent emergent X-ray spectrum from the radiative shock, focusing on both the CRSF and the X-ray continuum, under diverse conditions. The accretion column was characterized by cylindrical symmetry, and the radiative shock was treated as a mathematical discontinuity.

Results. We find that a power law, hard X-ray continuum, and a CRSF are naturally produced by the first-order Fermi energization as the photons criss-cross the shock. The depth and the width of the CRSF depend mainly on the transverse optical depth and the post-shock temperature. We show that the cyclotron-line energy centroid is shifted by ∼(20 − 30)% to lower energies compared to the classical cyclotron energy; this is due to the Doppler boosting between the shock reference frame and the bulk-motion frame. We demonstrate that a “bump” feature arises in the right wing of the CRSF due to the up-scattering of photons by the accreting plasma and extends to higher energies for larger optical depths and post-shock temperatures.

Conclusions. We conclude that resonant Compton scattering of photons by electrons in a radiative shock is efficient in producing a power-law X-ray continuum with a high-energy cutoff accompanied by a prominent CRSF. The implications of the Doppler effect on the centroid of the emergent absorption feature must be considered if an accurate determination of the magnetic field strength is desired.
Evolution of coronal mass ejections with and without sheaths from the inner to the outer heliosphere: Statistical investigation for 1975 to 2022
Authors: Larrodera C. , Temmer M.
Published: March 2024

Aims. This study covers a thorough statistical investigation of the evolution of interplanetary coronal mass ejections (ICMEs) with and without sheaths through a broad heliocentric distance and temporal range. The analysis treats the sheath and magnetic obstacle (MO) separately in order to gain more insight on their physical properties. In detail, we aim to unravel different characteristics of these structures occurring over the inner and outer heliosphere.

Methods. The method is based on a large statistical sample of ICMEs probed over different distances in the heliosphere. For this, information about detection times for the sheath and MO from 13 individual ICME catalogs was collected and crosschecked. The time information was then combined into a main catalog that was used as the basis for the statistical investigation. The data analysis based on this catalog covers a large number of spacecraft missions, enabling in situ solar wind measurements from 1975 to 2022. This allowed us to study the differences between solar cycles.

Results. All the structures under study (sheath, MO with and without sheath) show the biggest increase in size together with the largest decrease in density at a distance of ∼0.75 AU. At 1 AU, we found different sizes for MOs with and without a sheath, with the former being larger. Up to 1 AU, the upstream solar wind shows the strongest pileup close to the interface with the sheath. For larger distances, the pileup region seems to shift, and it recedes from that interface further into the upstream solar wind. This might refer to a change in the sheath formation mechanism (driven versus non-driven) with heliocentric distance, suggesting the relevance of the CME propagation and the expansion behavior in the outer heliosphere. A comparison to previous studies showed inconsistencies over the solar cycle, which makes more detailed studies necessary in order to fully understand the evolution of ICME structures.
Eccentric binaries: Periastron events and tidal heating
Authors: Koenigsberger G. , Estrella-Trujillo D.
Published: March 2024

Context. Binary stars cannot be fully understood without assessing the interaction effects between the two components and the impact of these effects on observational diagnostics. Periastron brightening events, also known as the heartbeat phenomenon, are a clear manifestation of this type of interaction.

Aims. We aim to explore the role of tidal shear energy dissipation in stars undergoing periastron brightening events.

Methods. We performed a computation from first principles that uses a quasi-hydrodynamic Lagrangian scheme to simultaneously solve the orbital motion and the equations of motion of a 3D grid of volume elements covering the inner, rigidly rotating “core” of a tidally perturbed star. The equations of motion include the gravitational acceleration of both stars, the centrifugal, Coriolis, gas pressure accelerations, and viscous coupling between volume elements. The method is illustrated for a grid of model binary systems with a 10 M⊙ primary that is perturbed by a 6.97 M⊙ companion in eccentric orbits (e = 0 − 0.7). The model is then applied to the heartbeat star MACHO 80.7443.1718.

Results. We find an increase by factors ∼10−6–10−3 in tidal shear energy dissipation at periastron, consistent with the majority of observed heartbeat stars. The magnitude of the periastron effect correlates with the degree of departure from synchronicity: stars rotating much faster or much slower than the synchronous rate at periastron present the strongest effect. We confirm that for eccentricities ≤0.3, pseudo-synchronization occurs for 0.8 < ω/Ωave < 1, where Ωave is the average orbital angular velocity. The minimum energy rotation rate (pseudo-synchronism) for e = 0.5 and 0.7 occurs for 1.0 < ω/Ωave < 1.15. The tidal shear energy dissipation model reproduces from first principles the ∼23% maximum brightness enhancement at periastron of MACHO 80.7443.1718.

Conclusions. Our results suggest that the magnitude and shape of the heartbeat signal may serve as diagnostics for the internal stellar rotation and turbulent viscosity values.
The influence of holding time on the microstructure and properties of TLP joints of Q355 steel
Authors: Huang Bensheng , Pu Chengyang , Ju Chunyan , Peng Leizhen , Shen Guoqu , Wu Yanqiu
Published: March 2024

Using BNi as the interlayer material, transient liquid phase diffusion welding experiments were conducted on Q355 steel at a welding temperature of 1050 °C under different holding times (10, 15, 20, 25 min). The welded joint microstructure, element diffusion migration, and phase composition were analyzed by using modern analytical testing instruments such as optical microscope (OM), scanning electron microscope (SEM), and energy dispersive spectrometer (EDS). The mechanical properties of the joint were tested and analyzed by using a microhardness tester, universal testing machine, and impact testing machine. The electrochemical corrosion property of the welded joint was analyzed and studied by using an electrochemical workstation. The results showed that under the conditions of 1050 °C and 6 MPa pressure, the Q355 steel TLP welded joint with better property could be obtained with a 20-min holding time. With the increase of holding time, the width of the bonding interface layer increased first and then decreased, and the microstructure tended to be more uniform. The shear strength gradually increased, reaching a maximum of 496.7 MPa (25 min), but the impact toughness increased first and then decreased, with a maximum of 250.61 J/cm2 (20 min). The corrosion resistance of the joint also improved first and then weakened.
Comparative study on grinding kinetics behavior of vanadium-titanium magnetite ore before and after microwave pretreatment
Authors: Wang Junpeng , Jiang Tao
Published: March 2024

Vanadium-titanium magnetite underwent closed circuit crushing before and after microwave pretreatment. Subsequently, batch grinding tests were conducted on the crushed products, with varying grinding times. Ultimately, the m-order grinding kinetics model of the ore was established both before and after microwave pretreatment. The results show that microwave pretreatment causes a significant increase in the number of micro-cracks on the ore's surface. Moreover, the specific surface area and pore volume of the ore increase by 17.29% and 40.98% respectively. These changes result in a reduction in the mechanical properties of the ore. During the grinding tests, the number of micro-cracks is found to be the primary factor influencing the grinding speed in the initial stage. However, as the grinding progresses, the grinding probability becomes the main factor affecting the grinding speed. The coarse particle size of the microwave-treated ore exhibits a significantly higher grinding speed than the untreated ore. Conversely, the grinding speed of fine particle size ore change slightly. The application of microwave-assisted grinding for vanadium-titanium magnetite proves advantageous in improving the particle size composition of the grinding product. Consequently, this can lead to enhanced separation efficiency and concentrate quality.
Innovative B-PA binder for enhanced cold pelletization: a sustainable strategy for utilizing iron-containing dust and sludge
Authors: Li Guangshi , Xie Wenyu , Zhuang Qingyun , Pang Zhongya , Sun Chenteng , Geng Shuhua , Zou Xingli , Lu Xionggang
Published: March 2024

A large amount of iron dust and sludge is produced in the process of iron and steel metallurgy, and its efficient utilization has important economic value and environmental significance. In this study, a method of cold-bonded aggregate is used to co-process stainless steel pickling sludge (SSPS) and gravity dust (GD). The preparation process parameters of cold-bonded pellet are optimized. The role mechanism of the binder on cold-bonded aggregates is studied, and a new type of composite binder, bentonite-plant asphalt (B-PA), is invented. The optimal ratio of bentonite to plant asphalt is determined to be 3:1. The metallurgical performance of B-PA agglomerates is tested, with results showing an RDI+3.15 at 93.6%, a RI at 79.3%, an RSI at 14.2%, a DI at 4.01%, and a thermal cracking temperature reaching 721 °C. The microstructure of the agglomerates after performance testing is characterized using XRD and SEM. This cold-bonding pelletization technology is expected to be widely used in the efficient comprehensive utilization of metallurgical dust in the future, which is of great significance for reducing costs, increasing efficiency, and promoting green environmental protection in the steel industry.
Influence of thickness scaling on the electronic structure and optical properties of oxygen deficient BaBiO3-δ thin films grown on SrTiO3-buffered Si(001) substrate
Authors: Ahmed I. , Korytov M. , Sergeant S. , Nuytten T. , Conard T. , De Gendt S. , Merckling C.
Published: March 2024

BaBiO3 has attracted a lot of research attention since it was discovered as the parent compound for the high-Tc superconducting BaPbxBi1–xO3 and Ba1–xKxBiO3. In its pure state, BaBiO3 is an insulator due to the presence of a breathing distortion of the BiO6 octahedra. The distortion is attributed to the valency of Bi in the compound being charge-ordered in the form of Bi3+ and Bi5+ along the lattice, resulting in alternating expanded or contracted BiO6 octahedra. The interaction between the electronic properties and the thickness of the thin film is crucial to study. We conducted a thorough study to investigate the effect of the thickness reduction of BaBiO3-δ grown on SrTiO3-buffered Si substrates on the optical properties as well as the Bi electronic structure of the thin films. We conclude that modifications in the valency of Bi in the ultra-thin film regime result in an optically conducting layer.
Dielectric multilayers impact on radiation-induced charge accumulation in highly sensitive oxide field effect transistors
Authors: Bordoni Camilla , Ciavatti Andrea , Cortinhal Mariana , Pereira Maria , Cramer Tobias , Barquinha Pedro , Fraboni Beatrice
Published: March 2024

Radiation dosimetry is crucial in many fields where the exposure to ionizing radiation must be precisely controlled to avoid health and environmental safety issues. Among solid state detectors, we recently demonstrated that Radiation sensitive OXide Field Effect Transistors (ROXFETs) are excellent candidates for personal dosimetry thanks to their fast response and high sensitivity to x rays. These transistors use indium–gallium–zinc oxide as a semiconductor, combined with a dielectric based on high-permittivity and high-atomic number materials. Here, we present a study on the ROXFET gate dielectric fabricated by atomic layer deposition, where we compare single- and multi-layer structures to determine the best-performing configuration. All the devices show stable operational parameters and high reproducibility among different detectors. We identified an optimized bi-layer dielectric structure made of tantalum oxide and aluminum oxide, which demonstrated a sensitivity of (63 ± 2) V/Gy, an order of magnitude larger than previously reported values. To explain our findings, we propose a model identifying the relevant charge accumulation and recombination processes leading to the large observed transistor threshold voltage shift under ionizing radiation, i.e., of the parameter that directly defines the sensitivity of the device.
A numerical study on the hydrodynamics of a swimming crocodile model
Authors: He Junxuan , Feng Chuangxin , Kuang Le , Han Lulu , Jia Wenzhen , Bai Honglei , Jiang Jianping
Published: March 2024

Aiming to uncover the propulsion mechanisms underlying a cruising crocodile, we conduct computational fluid dynamics (CFD) simulations on the flow around a simplified three-dimensional model of the Crocodylus siamensis. The locomotion of the crocodile model is realized through undulating its body and tail, mimicking a crocodile-like swimming pattern. At a cruising speed of U∞ = 0.5 m/s (corresponding to a Reynolds number Re = 9.95 × 105 based on U∞ and the body length L), the hydrodynamics of the crocodile model are investigated, taking into account effects of the undulation parameters (i.e., amplitude A and frequency f). The normalized undulation parameters cover broad ranges of 0.6 ≤ A* = A/W ≤ 1.0 and 0.25 ≤ f * = fW/U∞ ≤ 0.625, where W is the body width. The CFD simulations are conducted in ANSYS Fluent, with the SST k–ω turbulence model and user-defined functions for dynamic mesh being used. Numerical results reveal that A* and f * render profound effects on the hydrodynamic performance of the crocodile model. The time-mean axial force coefficient (CA¯) and power coefficient (C¯Power) exhibit rapid growth with increasing A* and/or f *, while the root mean square lateral force coefficient (Cy,rms) is more dependent on f * than on A*. It is further found that, irrespective of A*, CA¯ and C¯Power can be well scaled with Strouhal number St (= 2fA/U∞) or St2(1 − U∞/c). Furthermore, distinct flow patterns are observed in the wake of the crocodile model undulating at different St, corresponding to the drag, transition (or cruising), and thrust type swimming, respectively. Discussion is made on the wake flow structures and their connections to the generation of the hydrodynamic forces. The findings from this work contribute to the understanding of the propulsion mechanisms of the swimming crocodile, meaningful for the design of efficient biomimetic amphibious robots.
Dual analysis of stability in plane Poiseuille channel flow with uniform vertical crossflow
Authors: Kumar D. L. Shivaraj , Basavaraj M. S.
Published: March 2024

In this paper, we investigate the effect of uniform vertical crossflow on the plane Poiseuille channel flow. The derivation and linearization of the Navier–Stokes equations are performed to enable numerical solution through the fourth-order Orr–Sommerfeld equation. The Chebyshev collocation method is employed for this purpose. A dual approach is employed to examine the basic velocity profile, involving both reference velocity analysis (z = 0) and maximum streamwise velocity analysis (z = zmax). The two approaches provide distinct perspectives on the flow and may yield different stability predictions, depending on the values of the parameters used. Modal analysis is conducted to comprehend the asymptotic behavior of the system, achieved through the plotting of eigenspectrum, neutral stability curves, and growth rate curves for disturbances. Accurate values of critical triplets are obtained, aligning with the existing literature. The non-modal analysis is performed to understand the short-term behavior of the system, aided by pseudospectra, evolutionary patterns of energy amplification of the disturbances G(t) over time, and delineation of regions, indicating stability, potential instability, and instability. The collective results from both analyses reveal that the crossflow serves as a dual agent, contributing to both the stabilization and destabilization of the system.
Disorder-induced non-linear growth of fingers in immiscible two-phase flow in porous media
Authors: Sinha Santanu , Méheust Yves , Fyhn Hursanay , Roy Subhadeep , Hansen Alex
Published: March 2024

Immiscible two-phase flow in porous media produces different types of patterns depending on the capillary number Ca and viscosity ratio M. At high Ca, viscous instability of the fluid–fluid interface occurs when the displaced fluid is the more viscous, and leads to viscous fingering, which is believed to exhibit the same growth behavior as the viscously-unstable fingers observed in Hele–Shaw cells by Saffman and Taylor [“The penetration of a fluid into a porous medium or Hele–Shaw cell containing a more viscous liquid,” Proc. R. Soc. London 245, 312 (1958)], or as diffusion-limited aggregates (DLA). In such Laplacian growth processes, the interface velocity depends linearly on the local gradient of the physical field that drives the growth process (for two-phase flow, the pressure field). However, a non-linear power-law dependence between the flow rate and the global pressure drop, reminiscent of what has also been observed for steady-state two-phase flow in porous media, was evidenced experimentally for the growth of viscously-unstable drainage fingers in two-dimensional porous media, 20 years ago. Here, we revisit this flow regime using dynamic pore-network modeling and explore the non-linearity in the growth properties. We characterize the previously unstudied dependencies of the statistical finger width and non-linear growth law's exponent on Ca, and discuss quantitatively, based on theoretical arguments, how disorder in the capillary barriers controls the growth process' non-linearity, and why the flow regime crosses over to Laplacian growth at sufficiently high Ca. In addition, the statistical properties of the fingering patterns are compared to those of Saffman–Taylor fingers, DLA growth patterns, and the results from the aforementioned previous experimental study.
Elastin recoil is driven by the hydrophobic effect
Authors: Jamhawi Nour M. , Koder Ronald L. , Wittebort Richard J.
Published: March 2024

Elastin is an extracellular matrix material found in all vertebrates. Its reversible elasticity, robustness, and low stiffness are essential for the function of arteries, lungs, and skin. It is among the most resilient elastic materials known: During a human lifetime, arterial elastin undergoes in excess of 2 × 10
9
stretching/contracting cycles without replacement, and slow oxidative hardening has been identified as a limiting factor on human lifespan. For over 50 y, the mechanism of entropic recoil has been controversial. Herein, we report a combined NMR and thermomechanical study that establishes the hydrophobic effect as the primary driver of elastin function. Water ordering at the solvent:protein interface was observed as a function of stretch using double quantum
2
H NMR, and the most extensive thermodynamic analysis performed to date was obtained by measuring elastin length and volume as a function of force and temperature in normal water, heavy water and with cosolvents. When stretched, elastin’s heat capacity increases, water is ordered proportional to the degree of stretching, the internal energy decreases, and heat is released in excess of the work performed. These properties show that recoil in elastin under physiological conditions is primarily driven by the hydrophobic effect rather than by configurational entropy as is the case for rubber. Consistent with this conclusion are decreases in the thermodynamic signatures when cosolvents that alter the hydrophobic effect are introduced. We propose that hydrophobic effect-driven recoil, as opposed to a configurational entropy mechanism where hardening from crystallization can occur, is the origin of elastin’s unusual resilience.
The awkward rhetoric of Spanish liberalism
Authors: Rosales José María
Published: March 2024

This article explores the ideological controversies around Spanish liberalism through the story of the Citizens
party – from its rise in 2006 through 2023, after a sequence of electoral defeats that almost certified its demise. Born as a
regional party in Catalonia with an anti-nationalist platform focused on linguistic policies, in national politics it fostered a
liberal agenda. The article examines Citizens’ politics of language hiding the party’s liberal identity because of its association
to right-wing outlooks. At its founding documents there was an amalgam of liberal and social democratic constitutional values
inspiring the party’s political approach. No earnest question was made of their difficult accommodation, given their disparity at
the policy level. In 2017 an internal debate arouse, and from 2019 a number of electoral setbacks accelerated it. By then the
liberal language legitimizing its passage from regional into a national party had lost its civic appeal.
Excitation and ionization of OCS molecules in strong UV and NIR laser fields
Authors: Shi 师 Huijun 慧军 , Liu 刘 Yang 洋 , Sun 孙 Tian 添 , Lv 吕 Hang 航 , Xu 徐 Haifeng 海峰
Published: March 2024

Rydberg state excitation (RSE) is a highly non-linear physical phenomenon that is induced by the ionization of atoms or molecules in strong femtosecond laser fields. Here we observe that both parent and fragments (S, C, OC) of the tri-atomic molecule carbonyl sulfide (OCS) can survive strong 800 nm or 400 nm laser fields in high Rydberg states. The dependence of parent and fragment RSE yields on laser intensity and ellipticity is investigated in both laser fields, and the results are compared with those for strong-field ionization. Distinctly different tendencies for laser intensity and ellipticity are observed for fragment RSE compared with the corresponding ions. The mechanisms of RSE and strong-field ionization of OCS molecules in different laser fields are discussed based on the experimental results. Our study sheds some light on the strong-field excitation and ionization of molecules irradiated by femtosecond NIR and UV laser fields.
Upgrade of the ATLAS Level-0 TGC Endcap Muon Trigger for HL-LHC
Authors: Kawamoto C. ,   the ATLAS collaboration
Published: March 2024

The Level-0 endcap muon trigger system for the ATLAS experiment at the HL-LHC, which performs a fast muon reconstruction using the Thin Gap Chamber (TGC), is being developed to cope with more than three times higher luminosity environment and achieve a better performance. The efficiency in the high-p
T region was found to be 9% higher than the current system. The TGC hit signals digitized at the frontend electronics are sent to the backend, and muon candidates are reconstructed using the hits. Then, the candidates are combined with information from other detectors to refine transverse momentum (p
T) reconstruction and reduce fake trigger candidates. The precise online estimation of p
T allows us to apply highly efficient trigger condition to select events that contains muons with high p
T.
The Sector Logic (SL) is responsible for the online fast reconstruction in the L0 Muon Trigger system, and the algorithms are implemented in a large-scale modern FPGA on the SL. Each step of the reconstruction algorithms is first implemented as individual modules, and all trigger algorithms run sequentially as a chain in a combined firmware. The trigger algorithms are being tested on the prototype trigger board, the SL. The resource usage of the FPGA is reasonable and the trigger latency is within the acceptable limit.
Study of cosmogenic activation in 76Ge enriched germanium detectors during fabrication and transportation above ground
Authors: Nie Qiyuan , Zeng Zhi , Ma Hao , Yang Litao , Yue Qian , Cheng Jianping
Published: March 2024

Rare event search experiments using germanium detectors are
operated in underground laboratories to minimize the background
induced by cosmic rays. However, the cosmogenic activation in
germanium crystals on the ground during fabrication and
transportation generates long half-life radionuclides and
contributes a considerable background. We simulated the production
rates of cosmogenic radionuclides in germanium and calculated the
specific activities of cosmogenic radionuclides according to the
scheduled fabrication and transportation processes of 76Ge
enriched germanium detectors. The impact of cosmogenic background in
germanium crystals for the next generation CDEX experiment was
assessed with the scheduled exposure history above ground.
From design and construction to operation of the APPLE undulator at TPS
Authors: Chung Ting-Yi , Chang Cheng-Hsing , Chen Hsiung , Chen Hui-Huang , Hwang Ching-Shiang
Published: March 2024

The APPLE type of Elliptically Polarized Undulator (EPU) not
only serves as a crucial circularly polarized light source in
existing accelerator facilities but also acts as a standard light
source for soft X-rays at the Taiwan Photon Source (TPS). Up to the
present, we have autonomously designed, constructed, and operated
various EPU configurations. The experience gleaned from the
construction of various designs and the choice of material will be
outlined in this paper. We also elaborate upon the actions taken to
address the adverse effects on the magnetic fields due to the
characteristics of non-identical magnets and mechanical
deformation. In particular, a method for correction of discrepancies
in the magnetic field of the EPU with operation in numerous phase
modes employing iron shims is described. In addition, we also
discuss the adverse effects on the storage ring that must be dealt
with for stable operation of the EPU at the TPS and optimization of
the magnetic field during the laboratory construction phase. This
paper will further explain management issues related to the
susceptibility of the EPU to radiation damage. The comprehensive
experience related to the EPU at the TPS, from design and
construction to operation will be presented in this paper.
The multi-sightline compact D-D neutron spectrometers based on CLYC7-scintillator for beam ion anisotropy study in LHD
Authors: Liao L.Y. , Ogawa K. , Isobe M. , Sangaroon S. , Kawamoto Y. , Zhong G.Q. , Fan T.S.
Published: March 2024

Three compact neutron emission spectrometers (CNESs) based
on the novel inorganic scintillator Cs2LiYCl6:Ce with 99% 
7Li-enrichment (CLYC7) were newly installed in different lines
of sight in the Large Helical Device (LHD) to study the anisotropy
of the velocity distribution of the beam ions. Neutron energy
spectra measurements using multi-sightline CNESs were performed
under neutral-beam (NB)-heated deuterium plasma. A significant
Doppler shift of the deuterium-deuterium (D-D) neutron energy
induced by different NB heating and different lines of sight was
observed. The measured peak neutron energies were nearly consistent
with those calculated by the simple two-body kinematics of the D-D
reaction using the tangency radii of CNESs and NBs. These results
demonstrated the capabilities of the CNESs for neutron energy
spectra measurements and the study of fast-ion physics in magnetic
confinement fusion research.
Search algorithm on strongly regular graph by lackadaisical quantum walk
Authors: Peng Fangjie , Li Meng , Sun Xiaoming
Published: March 2024

Quantum walk is a widely used method in designing quantum algorithms. In this article, we consider the lackadaisical discrete-time quantum walk (DTQW) on strongly regular graphs (SRG). When there is a single marked vertex in a SRG, we prove that lackadaisical DTQW can find the marked vertex with asymptotic success probability 1, with a quadratic speedup compared to classical random walk. This paper deals with any parameter family of SRG and argues that, by adding self-loops with proper weights, the asymptotic success probability can reach 1. The running time and asymptotic success probability matches the result of continuous-time quantum walk, and improves the result of DTQW.
Bioreactor-based stem cell therapy for liver fibrosis
Authors: Yan Mengchao , Yao Jia , Xie Ye , Jiang Pan , Yan Jun , Li Xun
Published: March 2024

Stem cell therapy, achieved using mesenchymal stem cells (MSCs), has been highlighted for the treatment of liver fibrosis. Infusion into the circulatory system is a traditional application of MSCs; however, this approach is limited by phenotypic drift, stem cell senescence, and vascular embolism. Maintaining the therapeutic phenotype of MSCs while avoiding adverse infusion-related reactions is the key to developing next-generation stem cell therapy technologies. Here, we propose a bioreactor-based MSCs therapy to avoid cell infusion. In this scheme, 5% liver fibrosis serum was used to induce the therapeutic phenotype of MSCs, and a fluid bioreactor carrying a co-culture system of hepatocytes and MSCs was constructed to produce the therapeutic medium. In a rat model of liver fibrosis, the therapeutic medium derived from the bioreactor significantly alleviated liver fibrosis. Therapeutic mechanisms include immune regulation, inhibition of hepatic stellate cell activation, establishment of hepatocyte homeostasis, and recovery of liver stem cell subsets. Overall, the bioreactor-based stem cell therapy (scheme) described here represents a promising new strategy for the treatment of liver fibrosis and will be beneficial for the development of ‘cell-free’ stem cell therapy.
Quasi-Periodic Traveling Waves on an Infinitely Deep Perfect Fluid Under Gravity
Authors: Feola Roberto , Giuliani Filippo
Published: March 2024

We consider the gravity water waves system with a periodic one-dimensional interface in infinite depth and we establish the existence and the linear stability of small amplitude, quasi-periodic in time, traveling waves. This provides the first existence result of quasi-periodic water waves solutions bifurcating from a completely resonant elliptic fixed point. The proof is based on a Nash–Moser scheme, Birkhoff normal form methods and pseudo differential calculus techniques. We deal with the combined problems of small divisors and the fully-nonlinear nature of the equations.

The lack of parameters, like the capillarity or the depth of the ocean, demands a refined nonlinear bifurcation analysis involving several nontrivial resonant wave interactions, as the well-known “Benjamin-Feir resonances”. We develop a novel normal form approach to deal with that. Moreover, by making full use of the Hamiltonian structure, we are able to provide the existence of a wide class of solutions which are free from restrictions of parity in the time and space variables.
Rapid fiber-detection technique by artificial intelligence in phase-contrast microscope images of simulated atmospheric samples
Authors: Yamamoto Takashi , Iwasaki Kazuharu , Iida Yukiko , Yuki Ken-ichi , Nakaji Fumihiro , Yamashiro Hayato , Toyoguchi Toshiyuki , Terazono Atsushi
Published: March 2024

Since the manufacture, import, and use of asbestos products have been completely abolished in Japan, the main cause of asbestos emissions into the atmosphere is the demolition and removal of buildings built with asbestos-containing materials. To detect and correct asbestos emissions from inappropriate demolition and removal operations at an early stage, a rapid method to measure atmospheric asbestos fibers is required. The current rapid measurement method is a combination of short-term atmospheric sampling and phase-contrast microscopy counting. However, visual counting takes a considerable amount of time and is not sufficiently fast. Using artificial intelligence (AI) to analyze microscope images to detect fibers may greatly reduce the time required for counting. Therefore, in this study, we investigated the use of AI image analysis for detecting fibers in phase-contrast microscope images. A series of simulated atmospheric samples prepared from standard samples of amosite and chrysotile were observed using a phase-contrast microscope. Images were captured, and training datasets were created from the counting results of expert analysts. We adopted 2 types of AI models—an instance segmentation model, namely the mask region-based convolutional neural network (Mask R-CNN), and a semantic segmentation model, namely the multi-level aggregation network (MA-Net)—that were trained to detect asbestos fibers. The accuracy of fiber detection achieved with the Mask R-CNN model was 57% for recall and 46% for precision, whereas the accuracy achieved with the MA-Net model was 95% for recall and 91% for precision. Therefore, satisfactory results were obtained with the MA-Net model. The time required for fiber detection was less than 1 s per image in both AI models, which was faster than the time required for counting by an expert analyst.
Tackling reference bias in genotyping by using founder sequences with PanVC 3
Authors: Norri Tuukka , Mäkinen Veli
Published: March 2024

Overcoming reference bias and calling insertions and deletions are major challenges in genotyping. We present PanVC 3, a set of software that can be utilized as part of various variant calling workflows. We show that, by incorporating known genetic variants to a set of founder sequences to which reads are aligned, reference bias is reduced and precision of calling insertions and deletions is improved.

Availability and implementation

PanVC 3 and its source code are freely available at https://github.com/tsnorri/panvc3 and at https://anaconda.org/tsnorri/panvc3 under the MIT licence. The experiment scripts are available at https://github.com/algbio/panvc3-experiments.
Node-degree aware edge sampling mitigates inflated classification performance in biomedical random walk-based graph representation learning
Authors: Cappelletti Luca , Rekerle Lauren , Fontana Tommaso , Hansen Peter , Casiraghi Elena , Ravanmehr Vida , Mungall Christopher J , Yang Jeremy J , Spranger Leonard , Karlebach Guy , Caufield J Harry , Carmody Leigh , Coleman Ben , Oprea Tudor I , Reese Justin , Valentini Giorgio , Robinson Peter N
Published: March 2024

Motivation

Graph representation learning is a family of related approaches that learn low-dimensional vector representations of nodes and other graph elements called embeddings. Embeddings approximate characteristics of the graph and can be used for a variety of machine-learning tasks such as novel edge prediction. For many biomedical applications, partial knowledge exists about positive edges that represent relationships between pairs of entities, but little to no knowledge is available about negative edges that represent the explicit lack of a relationship between two nodes. For this reason, classification procedures are forced to assume that the vast majority of unlabeled edges are negative. Existing approaches to sampling negative edges for training and evaluating classifiers do so by uniformly sampling pairs of nodes.

Results

We show here that this sampling strategy typically leads to sets of positive and negative examples with imbalanced node degree distributions. Using representative heterogeneous biomedical knowledge graph and random walk-based graph machine learning, we show that this strategy substantially impacts classification performance. If users of graph machine-learning models apply the models to prioritize examples that are drawn from approximately the same distribution as the positive examples are, then performance of models as estimated in the validation phase may be artificially inflated. We present a degree-aware node sampling approach that mitigates this effect and is simple to implement.

Availability and implementation

Our code and data are publicly available at https://github.com/monarch-initiative/negativeExampleSelection.
Cross-context behavioural correlations and signals of aggression in females of a livebearing fish
Authors: Kolluru Gita R , Akky Yasmine J , Weissman Alana , Poore Hilary , Weiner Dana , Earley Ryan L
Published: March 2024

Behaviours can be adaptively correlated with each other and with other aspects of phenotype. We investigated behaviour across foraging, mating, and risk contexts in females of the poeciliid fish, Girardinus metallicus. We quantified relationships between these behaviours and aggression signals, body size, and reproductive output. Behaviours describing aggression and boldness, some of which were repeatable, were correlated in females. Aggression was signalled by the darkening of a black spot on the extended dorsal fin or by fin flaring. Spot darkening occurred during intra- and intersexual interactions and was positively correlated with interfemale aggression and negatively correlated with the time females spent following males, suggesting that it is an honest indicator of motivational state. In contrast, fin flaring was directed only at females and occurred more frequently in the foraging context. Larger females had fewer offspring and received fewer courtship displays, possibly because they were more aggressive to males. In contrast to studies of males, we found a negative relationship between rank order of boldness and aggression, consistent with either a trade-off or with selection favouring the negative relationship. Our results highlight the importance of studying females in model systems to uncover novel patterns and potentially meaningful departures from what is typically seen in males.
Morphological divergence of domatia in ant-free populations of the widespread Neotropical myrmecophyte Miconia tococa (Melastomataceae)
Authors: Bartimachi Alessandra , Pimenta Thais B , Telles Francismeire J , Vieira-Neto Ernane H M , Cardoso João C F , Vasconcelos Heraldo L , Costa Alan N
Published: March 2024

Co-evolving organisms experience multiple selection pressures that may lead to trait mismatches among different populations and sites. In defensive ant–plant mutualisms, host plants (myrmecophytes) produce specialized shelters (domatia) to harbour specialized ant-partners in exchange for protection against enemies. Although populations of myrmecophytes without ants occur in some locations, there are no records of changes in domatia morphology—at the population level—due to the absence of symbiotic ants. We conducted broad-scale samplings of Miconia tococa (Melastomataceae) populations across the Brazilian Cerrado and a 2-year transplant experiment to test whether domatia morphology changes when symbiotic ants are naturally absent. Domatia were 33.9% smaller in ant-free populations than in ant-inhabited populations. Transplants revealed that host plants from ant-inhabited sites still developed larger domatia than those from ant-free sites, even in the absence of ant-partners. These findings point to a change of M. tococa traits associated with biotic defences where symbiotic ants are absent. What may have begun as a plastic adjustment to ant-free environments appears to have been transformed into fixed (genetic) interpopulation differences over time, indicating a potential local destabilization of the mutualism or a mechanism to stabilize the interaction at the landscape scale.