bluuebunny/crossref_metadata_2025 huggingface dataset:
Association between Clinical/Radiographic Characteristics and Histopathological Diagnoses of Periapical Granuloma and Cyst
Authors: Banomyong Danuchit , Arayasantiparb Raweewan , Sirakulwat Kanoknuch , Kasemsuwan Jane , Chirarom Nannaphat , Laopan Nithiporn , Lapthanasupkul Puangwan
Published: January 2023

Objective The aim of this study was to determine the association between clinical/radiographic characteristics and histopathological diagnoses of periapical granuloma and cyst obtained from the teeth treated with endodontic microsurgery.

Materials and Methods The clinical, radiographic (periapical and cone-beam computed tomography), and histopathological data were collected from patients' dental records of endodontic microsurgery on the teeth with periapical lesions. These lesions were histopathologically diagnosed as either granuloma or cyst, at the Endodontic Clinic, Faculty of Dentistry, Mahidol University, Bangkok, Thailand, from 2016 to 2021 according to inclusion and exclusion criteria. The data were analyzed using bivariate analysis and a multinomial logistic regression at a significance level of p-value less than 0.05.

Results A total of 83 patients (58 females and 25 males) with an average age of 45 to 49.5 years old met the criteria including 68 periapical granulomas (81.9%) and 15 periapical cysts (18.1%). A periapical lesion involving multiple teeth in a periapical radiograph was significantly associated with the histopathological diagnosis of periapical cyst (p < 0.05). Such periapical lesion was six times more likely to be periapical cyst than periapical granuloma.

Conclusions A significant factor for predicting periapical cyst from periapical granuloma was the presence of a periapical lesion with multiple-teeth involvement in a dental radiograph.
Antimicrobial and Anti-Inflammatory Oral Effects of Fermented Lingonberry Juice—A One-Year Prospective Human Intervention Study
Authors: Pärnänen Pirjo , Lomu Sari , Räisänen Ismo T. , Tervahartiala Taina , Sorsa Timo
Published: January 2023

Objectives A 1-year prospective human intervention study was performed to examine the anticaries, anti-inflammatory, antiproteolytic, and antimicrobial effects of fermented lingonberry juice (FLJ), used as a mouthwash for a period of 6 months, followed by a 6-month washout period.

Materials and Methods Twenty-five adults were recruited from private dental clinics in Helsinki and Joensuu (Finland). Standard oral examinations and sample gatherings were performed at base level, 6 months, and 1 year for oral Streptococcus mutans (S. mutans), Candida, and Lactobacilli levels, and active matrix metalloprotease-8 (aMMP-8) levels, and for decayed, missing, filled teeth (DMFT), decayed, missing filled surfaces (DMFS) and decayed surfaces (DS) indexes, and probing pocket depths (PPDs), bleeding on probing (BOP), and visible plaque index (VPI). FLJ was used by the participants once daily for 30 seconds for 6 months. FLJ contains 0.212% (w/v) polyphenols, 3% (w/ v) sugars, and contains no excipients. Ten milliliters of FLJ were equal to 1 dL of lingonberry juice.

Statistical Analysis Statistical analyses were performed with nonparametric Friedman's test and pairwise post-hoc analysis with Dunn-Bonferroni test, SPSS (version 27; IBM) and p < 0.05 was considered as statistically significant.

Results The levels of S. mutans and Candida counts, DS, BOP, and VPI decreased significantly (p < 0.05) during the FLJ period. Lactobacilli counts increased significantly, while there was also significant difference in aMMP-8 levels, DMFT, and DMFS between the three measurement points. PPDs were not affected.

Conclusions The specially formulated FLJ may have a positive decreasing effect on S. mutans, and Candida counts as well as decrease low-grade inflammation and proteolytic burden in the oral mucosa and periodontal tissues. The beneficial effects to the oral cavity of FLJ mouthwash may be useful among patients with oral diseases, such as dental caries, periodontitis and candidosis.
A method for loading magneto-optical trap in an ultrahigh vacuum environment
Authors: Bhardwaj Kavish , Sarkar Sourabh , Ram S. P. , Tiwari V. B. , Mishra S. R.
Published: January 2023

We have developed a method that enables loading a magneto-optical trap (MOT) in an ultrahigh vacuum environment. Nearly 1.0 × 108 atoms of 87Rb are trapped in the MOT at ∼2.0×10−10 Torr base pressure in the chamber. After the MOT loading, we have successfully demonstrated the working of a quadrupole magnetic trap in this chamber with a lifetime of ∼15 s.
Head-on collision between two-counter-propagating electron acoustic soliton and double layer in an unmagnetized plasma
Authors: Akter Shahrina , Hafez M. G.
Published: January 2023

The head-on collision between two-counter-propagating electron acoustic solitons and double layers (DLs) in an unmagnetized collisionless multi-species plasma consisting of inertial cold electron fluid and (α, q)-distributed hot electrons and positrons has been analyzed with the stationary background of massive positive ions. For nonlinear analysis of colliding wave phenomena, the coupled Korteweg–de Vries equation (KdVE), modified KdVE (mKdVE), and standard Gardner equation have been derived by adopting the extended Poincaré–Lighthill–Kuo technique. The effect of non-dimensional parameters on the collisional KdV, mKdV, and Gardner solitons (GSs) and DLs has been examined in detail by considering the limiting cases of (α, q)-distributions. It is found that the plasma model supports (i) the compressive and rarefactive collisional KdV solitons and GSs, (ii) only compressive mKdV solitons, and (iii) only rarefactive collisional DLs. The rarefactive collisional solitons are more affected by nonextensivity and the increase of the temperature of electrons than their compressive counterpart, whereas the rarefactive collisional DLs only existed in the presence of nonthermality.
Nonlinear photonic disclination states
Authors: Ren Boquan , Wang Hongguang , Kartashov Yaroslav V. , Li Yongdong , Zhang Yiqi
Published: January 2023

Higher-order topological insulators are unusual materials that can support topologically protected states, whose dimensionality is lower than the dimensionality of the structure at least by 2. Among the most intriguing examples of such states are zero-dimensional corner modes existing in two-dimensional higher-order insulators. In contrast to corner states, recently discovered disclination states also belong to the class of higher-order topological states but are bound to the boundary of the disclination defect of the higher-order topological insulator and can be predicted using the bulk-disclination correspondence principle. Here, we present the first example of the nonlinear photonic disclination state bifurcating from its linear counterpart in the disclination lattice with a pentagonal or heptagonal core. We show that nonlinearity allows us to tune the location of the disclination states in the bandgap and notably affects their shapes. The structure of the disclination lattice is crucial for the stability of these nonlinear topological states: for example, disclination states are stable in the heptagonal lattice and are unstable nearly in the entire gap of the pentagonal lattice. Nonlinear disclination states reported here are thresholdless and can be excited even at low powers. Nonlinear zero-energy states coexisting in these structures with disclination states are also studied. Our results suggest that disclination lattices can be used in the design of various nonlinear topological functional devices, while disclination states supported by them may play an important role in applications, where strong field confinement together with topological protection are important, such as the design of topological lasers and enhancement of generation of high harmonics.
Scale-resolving simulations of the flow in a nuclear fuel bundle with a channel spacer grid using partially averaged Navier–Stokes and large-eddy simulation
Authors: Matozinhos Camila F. , Hassan Yassin
Published: January 2023

The objective of this study is to evaluate the capabilities of the Partially Averaged Navier–Stokes (PANS) method in simulations of the flow through a rod bundle representative of a nuclear fuel assembly with a channel-type spacer grid. In the PANS bridging turbulence model, filters can be applied to obtain any level of resolution from Reynolds Averaged Navier–Stokes (RANS) to Direct Numerical Simulation (DNS). The closure model is sensitive to the length-scale cutoff by means of unresolved to total kinetic energy ratio (fk) and unresolved to total dissipation ratio (fε). Simulations are conducted to study the effect of the cutoff of length scale on the results obtained for flow statistics at selected locations in the domain. The results obtained with different PANS filters are compared with Unsteady RANS (URANS), Large Eddy Simulation (LES), and experiments. The mean and fluctuating flow components are computed at a representative plane located at the inter-channel between rods. Other flow quantities analyzed include the pressure drop upstream and downstream of the spacer grid, the turbulent kinetic energy, and the unresolved eddy viscosity. Additionally, we use the Lumley triangle to study turbulence anisotropy and to compare the nature of the energy content captured with LES and one of the PANS models. It is shown that the PANS model with fk=0.4, which resolves 60% of the turbulent kinetic energy content, captures the most relevant flow physics and is a suitable modeling approach for this application.
The development of battery storage co-located with renewable energy in China: A policy-driven system dynamics approach
Authors: Liu Yuanxin , Ke Chentong , Yang Liyan , Liu Hui , Chen Yalan , Yuan Jiahai
Published: January 2023

Battery storage is widely regarded as an indispensable solution to the large-scale integration of intermittent renewable energy into the power grid. Being still too expensive by itself, battery storage is currently promoted in China for utility-scale grid-parity wind/solar projects with compulsive technical standards or voluntary allocation requirements for those additional renewable projects beyond grid integration capacity. Under mandatory policies, part of the revenue from renewable energy is used to pay for battery storage. Without a mature electricity market, the development of battery storage co-located with renewable energy would be largely dependent on policy design. This paper conducts a policy-driven system dynamics simulation on the development mechanism of battery storage co-located with renewable energy in China. The results show that the installed capacity growth of battery storage will mainly be driven by mandatory policies before 2024 and mandatory policies will become almost ineffective after 2028. However, mandatory policies may still dominate the development of battery storage after 2030 if the cost reduction is restrained. The conclusions provide theoretical support for the development of battery storage co-located with renewable energy in China. To minimize the adverse effect of mandatory policy, policymakers should keep close eyes on the advance in technology and power market and adjust the policy accordingly.
On the conservative phase-field method with the N-component incompressible flows
Authors: Xia Qing , Yang Junxiang , Li Yibao
Published: January 2023

This paper presents a conservative Allen–Cahn model coupled with the incompressible Navier–Stokes equation for tracking the interface with the N-component immiscible fluids system. The proposed conservative phase-field model can track the interface with large deformation in divergence-free velocity fields. The erroneous estimation of the normal vector is a challenging numerical issue for the interface capturing due to the appearance of spurious oscillations. The improved phase-field-based method combines the nonlinear preprocessing operation guided by the level-set method with local artificial viscosity stabilization to improve the computation of the discrete normal vector. The interfaces between different immiscible components are replaced by the transition region with finite thickness in the continuous phase field. The surface tension effects are represented with the continuous surface tension force in the system, which is not limited by the number of components. The third-order Runge-Kutta time discretization and second-order spatial discretization are applied for the multi-component system. To eliminate the spurious oscillations caused by discontinuous and steep gradient for capturing the shocks and sharp interfaces, we apply the third-order weighted essentially non-oscillatory method for the advection term. Several quantitative results of numerical tests, such as error estimation with the proposed method, comparative tests with different methods, and convergence rate for classical benchmark test, have been performed to illustrate that our method works well for the interface tracing issue with high numerical accuracy. In addition, various representative qualitative tests have been presented to demonstrate the applicability of our method.
Fluctuation characteristics of hull surface force of a four-screw vessel in oblique flow
Authors: Sun Shuai , Zhang Yuan , Guo Zeqing , Huang Zhengui
Published: January 2023

To study the influence of oblique flow on propeller fluctuation pressure characteristics of a four-screw vessel, the wake field and self-propulsion performance are calculated and analyzed utilizing computational fluid dynamics simulations. The characteristics of the wake field and propeller fluctuation pressure under different drift angle consisting of 0°, ±10°, and ±20° are compared and discussed in detail. The results show that negative drift angle affected the wake field of inside propeller more severely due to the generation of bilge vortex. The mean values of inside propeller fluctuation pressure are about 30% larger than those of the outside one, while the amplitudes of fluctuation pressure are reversed. The mean values of propeller fluctuation pressure experience a gradual decrease from β = −20° to 20° with an exception of inside propeller at β = −20° condition. The fluctuation amplitude of outside propeller is more affected by oblique flow due to the influence of oblique flow on flow separation point.
The spatial-temporal effects of wing flexibility on aerodynamic performance of the flapping wing
Authors: Peng Liansong , Pan Tianyu , Zheng Mengzong , Su Guanting , Li Qiushi
Published: January 2023

In this paper, three-dimensional fluid–structure interaction simulation of flapping of a flexible wing is carried out. The aerodynamic effect of the flexible wing can be explained by analyzing the spatial and temporal effects of wing flexibility on aerodynamic performance. It is concluded that the flexible wing can increase the average lift and the aerodynamic efficiency. The spatial influence of flexible deformation mainly comes from the contribution of camber. In the mid-downstroke, wing flexibility results in significant camber near the wingtip, which is conducive to the attachment of the leading-edge vortex to the wing surface, thus enhancing the ability of the wingtip to generate lift. The temporal influence of flexible deformation mainly comes from the contribution of twist and bend. The fast pitching-down rotation due to the wing twist in the early downstroke is conducive to the accumulation of vorticity. The spanwise bend of the flexible wing due to the aerodynamic force and inertia can increase the flapping amplitude, which accounts for the lift increase. The above spatial-temporal effects make the flexible wing have better performance in generating lift and aerodynamic efficiency. The results are beneficial to systematically understand the aerodynamic effects of insect wing deformation and can provide guidance for the wing design of micro aerial vehicles.
Coupled fire-atmosphere simulation of the 2018 Camp Fire using WRF-Fire
Authors: Shamsaei Kasra , Juliano Timothy W. , Roberts Matthew , Ebrahimian Hamed , Kosovic Branko , Lareau Neil P. , Taciroglu Ertugrul
Published: January 2023

Background Accurate simulation of wildfires can benefit pre-ignition mitigation and preparedness, and post-ignition emergency response management. Aims We evaluated the performance of Weather Research and Forecast-Fire (WRF-Fire), a coupled fire-atmosphere wildland fire simulation platform, in simulating a large historic fire (2018 Camp Fire). Methods A baseline model based on a setup typically used for WRF-Fire operational applications is utilised to simulate Camp Fire. Simulation results are compared to high-temporal-resolution fire perimeters derived from NEXRAD observations. The sensitivity of the model to a series of modelling parameters and assumptions governing the simulated wind field are then investigated. Results of WRF-Fire for Camp Fire are compared to FARSITE. Key results Baseline case shows non-negligible discrepancies between the simulated fire and the observations on rate of spread (ROS) and spread direction. Sensitivity analysis results show that refining the atmospheric grid of Camp Fire’s complex terrain improves fire prediction capabilities. Conclusions Sensitivity studies show the importance of refined atmosphere modelling for wildland fire simulation using WRF-Fire in complex terrains. Compared to FARSITE, WRF-Fire agrees better with the observations in terms of fire propagation rate and direction. Implications The findings suggest the need for further investigation of other possible sources of wildfire modelling uncertainties and errors.
Laser welding of ZrO2 ceramic and 304 stainless steel with Ag–Cu–Ti filler
Authors: Guo Zhijin , Zhang Yan , Lu Wenbin , Liu Yuqiang , Zeng Haoyuan
Published: January 2023

In this paper, the joining of ZrO2 ceramic and 304 stainless steel (SS) was realised by laser offset welding with AgCuTi filler metal. The heat was transferred from the molten pool to the solder through the unmelted SS. AgCuTi would diffuse to form eutectic products with low melting point, forming metallurgical reaction zone. The unmelted SS was retained by laser migration to avoid the mixing of molten solder and molten pool, which reduced the content of brittle phase in the joint. In addition, the crack-free welded joint with a tensile strength of 71 MPa was obtained. The elemental diffusion model was used to simulate the interfacial microstructure changes, and the microstructure was reasonably predicted by changing the welding parameters.
Flat Top Optical Frequency Combs Based on a Single-Core Quantum Cascade Laser at Wavelength of ∼ 8.7 μm
Authors: Ma Yu , Li Wei-Jiang , Xu Yun-Fei , Liu Jun-Qi , Zhuo Ning , Yang Ke , Zhang Jin-Chuan , Zhai Shen-Qiang , Liu Shu-Man , Wang Li-Jun , Liu Feng-Qi
Published: January 2023

We present optical frequency combs with a spectral emission of 48 cm−1 and an output power of 420 mW based on a single-core quantum cascade laser at λ ∼ 8.7 μm. A flat top spectrum sustains up to 130 comb modes delivering ∼ 3.2 mW of optical power per mode, making it a valuable tool for dual comb spectroscopy. The homogeneous gain medium, relying on a slightly diagonal bound-to-continuum structure, promises to provide a broad and stable gain for comb operating. Remarkably, the dispersion of this device is measured within 300 fs2/mm to ensure stable comb operation over 90% of the total current range. The comb is observed with a narrow beatnote linewidth around 2 kHz and has weak dependence on the applied current for stable comb operation.
Observation of Charge Density Wave in Layered Hexagonal Cu1.89Te Single Crystal
Authors: Gao Wenshuai , Chen Zheng , Wei Wensen , Yan Chao , Wang Shasha , Tang Jin , Zhang Ranran , Cheng Lixun , Nan Pengfei , Wang Jie , Han Yuyan , Xi Chuanying , Ge Binghui , He Lin , Du Haifeng , Ning Wei , Zhu Xiangde , Tian Mingliang
Published: January 2023

We report comprehensive transport, electron microscopy and Raman spectroscopy studies on transition-metal chalcogenides Cu1.89Te single crystals. The metallic Cu1.89Te displays successive metal-semiconductor transitions at low temperatures and almost ideal linear MR when magnetic field up to 33 T. Through the electron diffraction patterns, the stable room-temperature phase is identified as a 3 × 3 × 2 modulated superstructure based on the Nowotny hexagonal structure. The superlattice spots of transmission electron microscopy and scanning tunneling microscopy clearly show the structural transitions from the room-temperature commensurate I phase, named as C-I phase, to the low temperature commensurate II (C-II) phase. All the results can be understood in terms of charge density wave (CDW) instability, yielding intuitive evidences for the CDW formations in Cu1.89Te. The additional Raman modes below room temperature further reveal that the zone-folded phonon modes may play an important role on the CDW transitions. Our research sheds light on the novel electron features of Cu1.89Te at low temperature, and may provide potential applications for future nano-devices.
An additional simultaneous magnetic ordering and magneto-capacitive behavior with dielectric relaxation besides multiferroicity in Fe

1−x

Te
x
VO4
Authors: Bera Ganesh , Surampalli Akash , Prajapat Deepak , Mal P , Reddy V R , Kumar Kranti , Sagdeo Archna , Das Pradip , Turpu G R
Published: January 2023

Here we report the evidence of an additional magnetic ordering and frequency dispersive magneto-dielectric (MD) permittivity besides multiferroic behavior in Te4+ (S = 0) doped FeVO4. Two antiferromagnetic transitions similar to FeVO4 at ∼21.86 K (T

N
1

) and 16.03 K (T

N
2

) were observed in all samples. An additional novel defect clusters based magnetic ordering at relatively higher temperature (T

A
M
O

) ∼ 203 K is also observed from the magnetization. Evaluated magnetic moments show systematic decrease and the magnetic frustration factors show an increase with the increasing of Te4+ (S = 0) content. MD studies show stable ferroelectric ordering at spiral magnetic transition (T

N
2

) and the multiferroic order persists to the largest doping of Te (x = 0.10). The MD studies also reveal a magneto-capacitive (MC) behavior at T

A
M
O

(∼203 K) with a high dielectric constant and loss, and the possible reason for the magnetic ordering and MC behavior is ascribed to short range magnetic clustering arising out of defect based mechanisms. Mössbauer spectroscopic studies confirm local structural correlation with magnetic and ferroelectric ordering.
Heavy pnictogen chalcohalides for efficient, stable, and environmentally friendly solar cell applications
Authors: Choi Yong Chan , Nie Riming
Published: January 2023

Solar cell technology is an effective solution for addressing climate change and the energy crisis. Therefore, many researchers have investigated various solar cell absorbers that convert Sunlight into electric energy. Among the different materials researched, heavy pnictogen chalcohalides comprising heavy pnictogen cations, such as Bi3+ and Sb3+, and chalcogen-halogen anions have recently been revisited as emerging solar absorbers because of their potential for efficient, stable, and low-toxicity solar cell applications. This review explores the recent progress in the applications of heavy pnictogen chalcohalides, including oxyhalides and mixed chalcohalides, in solar cells. We categorize them into material types based on their common structural characteristics and describe their up-to-date developments in solar cell applications. Finally, we discuss their material imitations, challenges for further development, and possible strategies for overcoming them.
Energy dynamics, heat production and heat–work conversion with qubits: toward the development of quantum machines
Authors: Arrachea Liliana
Published: January 2023

We present an overview of recent advances in the study of energy dynamics and mechanisms for energy conversion in qubit systems with special focus on realizations in superconducting quantum circuits. We briefly introduce the relevant theoretical framework to analyze heat generation, energy transport and energy conversion in these systems with and without time-dependent driving considering the effect of equilibrium and non-equilibrium environments. We analyze specific problems and mechanisms under current investigation in the context of qubit systems. These include the problem of energy dissipation and possible routes for its control, energy pumping between driving sources and heat pumping between reservoirs, implementation of thermal machines and mechanisms for energy storage. We highlight the underlying fundamental phenomena related to geometrical and topological properties, as well as many-body correlations. We also present an overview of recent experimental activity in this field.
Magnetization AC losses in multilayer superconducting round cables with coinciding and opposite lay angles
Authors: Solovyov M , Šouc J , Kujovič T , Frolek L , Gömöry F
Published: January 2023

Superconducting cables with a circular cross-section are attractive for various applications, such as power transmission lines, current leads, and large magnetic coils. In the case of coated conductor (CC) tapes, such an arrangement can be achieved by wrapping the tapes in a helical fashion around a circular former. While a braid of Cu wires serves as the core for the CORC® cable, in the conductor-on-round-tube the CC tapes are laid in several layers on a tube. Traditionally, the tapes in the neighbouring layers are wound following an alternating sense of helicity. Then, the tape edges are raised due to the Poisson effect, causing local surface irregularity and pressing into subsequent layers. We have found that this effect is less deteriorating in the case of coinciding lay angles because then the tape edges create imprints that are parallel to the tape length. Here, we present the results of investigating the AC loss performance of this innovative arrangement and its comparison with the traditional architecture. Both verification possibilities—experimental testing of small laboratory models and numerical modelling— were used for this purpose.
Performance tests of ITER CS conductor samples from series production
Authors: Breschi M , Devred A , Macioce D , Mitchell N
Published: January 2023

The International Thermonuclear Experimental Reactor (ITER) magnet system is one of the most sophisticated superconducting magnet systems ever designed, with a stored energy of 51 GJ. The coils are wound from cable-in-conduit conductors made of superconducting and copper strands assembled into a multistage rope-type cable, inserted into a conduit of austenitic steel tubes. The ITER central solenoid (CS) works in pulsed mode, reaching a peak field of 13 T, thus allowing the induction of a high intensity current in the plasma of the ITER tokamak. This magnet consists of a stack of six modules which include around 125 t of Nb3Sn strands. The production of all CS conductors has been completed and module manufacturing is well underway; throughout the production phase, samples were cut at the extremities of the conductor unit lengths to undergo quality control tests. About 25% of the conductor short samples were tested in current and field at cryogenic conditions at the SULTAN facility in Villigen, Switzerland. This work reports the comparative analysis of the short samples set of test results.
Synergistically investigating the structural, magnetic, opto-electronic, and thermo-elastic traits of LaFe1−xNixO3 for novel electronic applications
Authors: Tariq Saad , Alrashdi Ayash O , Ahmed Afaq , Mubarak A A
Published: January 2023

Electronic materials have gained massive interest in the past few years. The fundamental reason is the growing industrial demands and efforts to discover novel low cost-effective materials. In this work, the influence of Ni substitution on LaFeO3 is presented in detail using the Kohn–Sham scheme of density functional theory. All studied compounds have shown good agreement with experimentally reported results. However, mechanical and optical results are reported for the first time for doped structures. The structural stability has been extensively checked through several stability criteria, such as, structural optimizations, elastic stability tests, and enthalpy of formation. Furthermore, the electronic and optical properties suggest highly conducting and reflecting phases of the studied compounds, respectively. The analysis of magnetic properties shows a decrease in magnetic moment value with an increase in Ni content due to Fe-Ni degeneracy. Mechanical analysis such as moduli of elasticity B, G, and Y has shown an increase in strength of 75% Ni substituted LaFeO3 by 24.5, 79.7, and 59.2%, respectively. Internal strain factor indicates majority bond flexibility, implying a potential application in flexible electronic devices.
Tuned electronic and magnetic properties in 3d transition metal doped VCl3 monolayer: a first-principles study
Authors: Ouettar Chaouki , Yahi Hakima , Zanat Kamel , Chibani Hosayn
Published: January 2023

Transition metal trihalides (MX3) are one of the two-dimensional (2D) materials families that have garnered a lot of attention, especially after the first experimental realization of an intrinsic ferromagnetic CrI3 monolayer. The vanadium trichloride VCl3 monolayer, which is a member of this family, has been proven to be a stable Dirac half-metal with exciting properties and intrinsic ferromagnetism. Using first-principle calculations based on the GGA+U method, we have enhanced the spintronic properties of the VCl3 monolayer by tuning its electronic and magnetic properties via substitutional doping with 3d transition metals. We have found that Sc-, Ti-doped VCl3 monolayer systems are ferromagnetic semiconductors with indirect band gaps, while the Cr-doped monolayer is a ferromagnetic semiconductor with a direct band gap. More interestingly, the Mn-doped and Fe-doped VCl3 monolayers exhibited exciting spin gapless semiconducting (SGS) and bipolar ferromagnetic semiconducting (BFMS) properties that are very desirable for spintronic applications. Furthermore, the Cr-, Mn-, and Fe-doped systems have revealed large magnetic moment reaching the value of 4.75 μ
B per unit cell, as well as an increased ferromagnetic stability in the Fe-doped case. By possessing these interesting properties, these TM-doped monolayers could be potential candidates for spintronics.
Spin-dependent transmission in curved graphene superlattice
Authors: El-hassouny Jaouad , Jellal Ahmed , Atmani El Houssine
Published: January 2023

We investigate spin-dependent transmission in a curved graphene superlattice of N cells where each one is made up of four regions. The first is concave, and the third is convex, two arcs of circles separated by a distance d from flat graphene sheets. The tunneling analysis allows us to determine all transmission and reflection channels associated with our system. As a result, we show that the number of cells acts by decreasing the transmissions with the same spin. We predict a solid spin-filtering effect when d and N are sufficiently large. Finally, it is determined that the degree and duration of suppression of the transmissions with the same spin over a range of energy are controllable using d.
Probing massive neutrinos with the Minkowski functionals of large-scale structure
Authors: Liu Wei , Jiang Aoxiang , Fang Wenjuan
Published: January 2023

Massive neutrinos suppress the growth of structure under their free-streaming scales. The effect is most prominent on small scales where the widely-used two-point statistics can no longer capture the full information. In this work, we study the signatures massive neutrinos leave on large-scale structure (LSS) as revealed by its morphological properties, which are fully described by 4 Minkowski functionals (MFs), and quantify the constraints on the summed neutrino mass Mν
from the MFs, by using publicly available N-body simulations. We find the MFs provide important complementary information, and give tighter constraints on Mν
than the power spectrum. Specifically, depending on whether massive neutrinos are included in the density field (the 'm' field) or not (the 'cb' field), we find the constraint on Mν
from the MFs with a smoothing scale of RG
= 5h
-1Mpc is 48 or 4 times better than that from the power spectrum. When the MFs are combined with the power spectrum, they can improve the constraint on Mν
from the latter by a factor of 63 for the 'm' field and 5 for the 'cb' field. Notably, when the 'm' field is used, the constraint on Mν
from the MFs can reach 0.0177eV with a volume of 1(
-1Gpc)3, while the combination of the MFs and power spectrum can tighten this constraint to be 0.0133eV, a 4.5σ significance on detecting the minimum sum of the neutrino masses. For the 'm' field, we also find the σ
8 and Mν
degeneracy is broken with the MFs, leading to stronger constraints on all 6 cosmological parameters considered in this work than the power spectrum.
Editorial for the Metrologia Focus Issue on Length Metrology
Authors: Lewis Andrew J , Yacoot Andrew
Published: January 2023

This Focus Issue of Metrologia was instigated by the Consultative Committee for Length’s Working Group on Strategic Planning when it met online in 2020 during the COVID-19 pandemic. Submission of articles started closely thereafter and was closed in September 2022. Covering a wide range of topics, the issue shows that despite the Coronavirus pandemic disrupting laboratory work, length metrology researchers have continued to deliver cutting edge research. The revised definition of the metre and its Mise en Pratique, both published in 2019, have stimulated further research and opened additional opportunities for developing length metrology capabilities. Articles related to the new Mise en Pratique are included in the issue, together with a range of articles demonstrating the breadth and ingenuity of current leading edge research in length metrology. A final paper indicates how metrology, with length used as an example, may be enhanced by a transition to a digital framework for realising the SI.
Absolute frequency measurement of the 87Sr optical lattice clock at NTSC using international atomic time
Authors: Lu Xiaotong , Guo Feng , Wang Yebing , Xu Qinfang , Zhou Chihua , Xia Jingjing , Wu Wenjun , Chang Hong
Published: January 2023

We report the absolute frequency measurement of the

5

s

2

1

S

0

→
5
s
5
p

3

P

0

transition in 87Sr optical lattice clock (Sr1) at National Time Service Center. Its systematic frequency shifts are evaluated carefully with a total relative uncertainty of

5.1
×

10

−
17

. The measured absolute frequency is 429 228 004 229 872.91(18) Hz with a relative uncertainty of

4.1
×

10

−
16

, with reference to the ensemble of primary and secondary frequency standards published in the Circular T bulletin by BIPM through a global navigation satellite system link.
Analysis of functional connectivity in depression based on a weighted hyper-network method
Authors: Shao Xuexiao , Kong Wenwen , Sun Shuting , Li Na , Li Xiaowei , Hu Bin
Published: January 2023

Objective. Brain connectivity network is a vital tool to reveal the interaction between different brain regions. Currently, most functional connectivity methods can only capture pairs of information to construct brain networks which ignored the high-order correlations between brain regions. Approach. Therefore, this study proposed a weighted connectivity hyper-network based on resting-state EEG data, and then applied to depression identification and analysis. The hyper-network model was build based on least absolute shrinkage and selection operator sparse regression method to effectively represent the higher-order relationships of brain regions. On this basis, by integrating the correlation-based weighted hyper-edge information, the weighted hyper-network is constructed, and the topological features of the network are extracted for classification. Main results. The experimental results obtained an optimal accuracy compared to the traditional coupling methods. The statistical results on network metrics proved that there were significant differences between depressive patients and normal controls. In addition, some brain regions and electrodes were found and discussed to highly correlate with depression by analyzing of the critical nodes and hyper-edges. Significance. These may help discover disease-related biomarkers important for depression diagnosis.
Epileptic seizure detection by using interpretable machine learning models
Authors: Zhao Xuyang , Yoshida Noboru , Ueda Tetsuya , Sugano Hidenori , Tanaka Toshihisa
Published: January 2023

Objective. Accurate detection of epileptic seizures using electroencephalogram (EEG) data is essential for epilepsy diagnosis, but the visual diagnostic process for clinical experts is a time-consuming task. To improve efficiency, some seizure detection methods have been proposed. Regardless of traditional or machine learning methods, the results identify only seizures and non-seizures. Our goal is not only to detect seizures but also to explain the basis for detection and provide reference information to clinical experts. Approach. In this study, we follow the visual diagnosis mechanism used by clinical experts that directly processes plotted EEG image data and apply some commonly used models of LeNet, VGG, deep residual network (ResNet), and vision transformer (ViT) to the EEG image classification task. Before using these models, we propose a data augmentation method using random channel ordering (RCO), which adjusts the channel order to generate new images. The Gradient-weighted class activation mapping (Grad-CAM) and attention layer methods are used to interpret the models. Main results. The RCO method can balance the dataset in seizure and non-seizure classes. The models achieved good performance in the seizure detection task. Moreover, the Grad-CAM and attention layer methods explained the detection basis of the model very well and calculate a value that measures the seizure degree. Significance. Processing EEG data in the form of images can flexibility to use a variety of machine learning models. The imbalance problem that exists widely in clinical practice is well solved by the RCO method. Since the method follows the visual diagnosis mechanism of clinical experts, the model interpretation results can be presented to clinical experts intuitively, and the quantitative information provided by the model is also a good diagnostic reference.
Spatial and temporal analysis of the bottleneck flow under different walking states with a moving obstacle
Authors: Xu Han , Ren Xiangxia , Song Weiguo , Zhang Jun , Saidahmed Rayyan
Published: January 2023

The regulation of a moving obstacle on crowd movement offers the possibility to enhance evacuation efficiency in emergency situations. In this paper, a series of controlled experiments are conducted to study the effect of the moving obstacle on crowd dynamics for pedestrians in three different competitive levels, which respectively correspond to three different walking states. The enhancement effects of the moving obstacle on evacuation efficiency for the crowd in the dual-task and high-motivated walking states are confirmed, and the positions of the moving obstacle are crucial. It is found that the moving obstacle diminishes the order of the trajectories for the crowd in the dual-task and normal walking states, while it boosts near the exit for the crowd in the high-motivated walking state. And the moving obstacle makes the linear backward propagations of stop-and-go wave disappear for the crowd in the dual-task and high-motivated walking states, but the frequency of stop behavior increases for the crowd in the dual-task and normal walking states. The profiles of evacuation time show that the moving obstacle impedes the pedestrian flow from the front of the exit and increases evacuation efficiency for the pedestrians near the walls of the exit. The analysis of time headway suggests that the moving obstacle with a gap of 1.0 m or 1.2 m to the exit can reduce the number of the pedestrians waiting near the exit for the crowd in the dual-task and high-motivated walking states. Besides, the gap of 0.8 m between the moving obstacle and the exit makes the conflicts at the exit is increased, but the gap of 1.0 m or 1.2 m makes the number of conflicts at the exit be reduced. This study helps the evacuation management of dense crowds and improves the design of facilities to facilitate pedestrian traffic.
Duality relations in single-file diffusion
Authors: Rizkallah Pierre , Grabsch Aurélien , Illien Pierre , Bénichou Olivier
Published: January 2023

Single-file transport, which corresponds to the diffusion of particles that cannot overtake each other in narrow channels, is an important topic in out-of-equilibrium statistical physics. Various microscopic models of single-file systems have been considered, such as the simple exclusion process, which has reached the status of a paradigmatic model. Several different models of single-file diffusion have been shown to be related by a duality relation, which holds either microscopically or only in the hydrodynamic limit of large time and large distances. Here, we show that, within the framework of fluctuating hydrodynamics, these relations are not specific to these models and that, in the hydrodynamic limit, every single-file system can be mapped onto a dual single-file system, which we characterise. This general duality relation allows us to obtain new results for different models, by exploiting the solutions that are available for their dual model.
The inequitable exposure of socially vulnerable groups to water shortages across the United States
Authors: Sanchez Leslie , Warziniack Travis , Knowles Michael
Published: January 2023

Socially vulnerable populations in the United States are bearing the highest costs of water scarcity, which is likely to worsen with climate change, population growth, and growing disparities between areas with high water demand and the location of available supplies. Prior research showing that socially vulnerable groups are inequitably exposed to water shortages has focused on singular dimensions of social vulnerability, typically in relatively localized geographies, leaving us with an incomplete understanding of the national scope of the shortage risks. This study combines data on surface water shortages with the U.S. Center for Disease Control’s Social Vulnerability Index (SVI) to spatially identify clusters of high-shortage, high-vulnerability hotspots from 71 195 census tracts across the conterminous United States. We estimate that 5 percent of the population of the lower 48 states—nearly 15 million people—lives in high-SVI, high-shortage hotspot areas. We examine the relationship between exposure to water shortage and (a) SVI, (b) SVI themes, and (c) 15 indicators used to construct SVI across the U.S. and within hotspots. We find evidence that water shortages constitute an environmental injustice, as multiple dimensions of social vulnerability are disproportionately exposed to water shortages. However, the distinct dimensions of vulnerability that are correlated with a higher probability of exposure to water shortage vary across regions and within hotspots, indicating that adaptation strategies will have to be tailored to their specific contexts. This statement is to certify that all Authors have seen and approved the manuscript being submitted. We confirm that the article is the Authors’ original work and that we have no conflicts of interest.
Compact laser spectroscopic sensor head prototype for time-resolved breath oxygen monitoring
Authors: Patrick Link , Wysocki Gerard
Published: January 2023

A small and lightweight optical sensor head prototype with a disposable airway adapter for continuous mainstream monitoring of oxygen at high sampling rate is designed and tested on an optical benchtop. In terms of its size and functionality, the sensor head design is similar to current capnography systems from leading medical equipment manufacturers, and it has been designed within constraints of potential applications in direct breath oxygen monitoring that require direct interaction with the gas inside a breathing tube. The measurement precision of 0.1% O2 with a 10 ms integration time are well within the performance required for breath O2 monitoring applications.
Exchange bias controlled antisymmetric-symmetric magnetoresistances in Fe3GeTe2/graphite/Fe3GeTe2 trilayer
Authors: Wu Qingmei , Cui Zhangzhang , Zhu Mo , Jiang Zhongyuan , Fu Zhengping , Lu Yalin
Published: January 2023

The magnetoresistance (MR) of spin values usually displays a symmetric dependence on the magnetic field. An antisymmetric MR phenomenon has been discovered recently that breaks the field symmetry and has the potential to realize multi-bit memory. In this work, we report a controllable switch between the antisymmetric and symmetric MRs and propose a multi-bit memory performance in Fe3GeTe2 (FGT)/graphite/FGT trilayer with modified vertical geometry. Via investigating the evolution of the antisymmetric MR depending on the spatial distribution, current direction, and magnetization configuration, we demonstrate that the antisymmetric MR results from the local nonequilibrium current through the trilayer. Furthermore, an exchange bias effect is induced which modifies the antisymmetric MR. A stable multi-bit memory is presented in the heterostructure. Such architecture for multi-state memory provides insights into other spin-valve structures to improve storage density.
Climatic fingerprint of spring discharge depletion in the southern Italian Apennines from 1601 to 2020 CE
Authors: Diodato Nazzareno , Ljungqvist Fredrik Charpentier , Fiorillo Francesco , Esposito Libera , Ventafridda Gerardo , Bellocchi Gianni
Published: January 2023

Annual mean spring discharge (ASD) is an important water supply source, essential for ecological systems and societies dependent on groundwater resources. Influenced by both regional and local climate fluctuations, the inter-annual variability of ASD represents a climate memory signal, significantly affected when the drought pattern manifests itself in changing climatic regimes. Gaining a better historical perspective on ASD changes requires extended time-series of discharge data and relevant climate drivers. Here, using a parsimonious model, we present a continuous (modelled) time-series of annual ASD for the karst spring of Caposele, in the Cervialto Massif of southern Italy, which is hitherto the longest (1601–2020 CE) such time-series for the entire Mediterranean region. The model was designed to capture the importance of large-scale seasonal (spring, autumn and winter) precipitation (hydro-meteorological factor), and flood and drought indices (climatological factor), and to be consistent with a sample (1920–2020 CE) of actual data. We show a limited overall sensitivity of ASD to climate variability, with a mean of 4.21 m3 s−1 and a drop from ∼1759 CE. With a mean value of ∼3.60 m3 s−1 after ∼1987 CE, ASD has revealed a substantial descending trend—possibly a fingerprint of recent warming—with a depletion of regional water reservoirs. These results highlight the need to strengthen the capacity of groundwater resources in the face of changing, and possibly enhanced, drought patterns in the Mediterranean region.