bluuebunny/crossref_metadata_2025 huggingface dataset:
Donor Finger Morbidity in Cross-Finger Flap: A Systematic Review and Meta-Analysis
Authors: Chakraborty Sourabh Shankar , Sahu Ranjit Kumar , Acharya Sudeshna , Goel Akhil Dhanesh , Midya Manojit , Kotu Suresh
Published: February 2023

Background The morbidity of donor finger in a cross-finger flap has not received as much importance as the outcomes of the flap itself. The sensory, functional, and aesthetic morbidity of donor fingers, reported by various authors, are often contradictory to each other. In this study, objective parameters for the sensory recovery, stiffness, cold intolerance, cosmetic outcome, and other complications in the donor fingers, reported in the previous studies, are systematically evaluated.

Methods This systematic review is reported using Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) protocol and was registered with the International prospective register of systematic reviews (PROSPERO registration no. CRD42020213721). Literature search was done using “cross-finger,” “heterodigital,” “donor finger,” and “transdigital” words. Data regarding demography, patients' number and age, follow-up duration and outcomes of donor finger, including 2-point discrimination, range of motion (ROM), cold intolerance, questionnaires, etc. were extracted from included studies. Meta-analysis was performed using MetaXL and risk of bias was evaluated using Cochrane risk of bias tool.

Results Out of the total 16 included studies, 279 patients were objectively evaluated for donor finger morbidity. Middle finger was most frequently used as donor. Static two-point discrimination seemed to be impaired in donor finger in comparison to contralateral finger. Meta-analysis of ROM suggested that statistically there is no significant difference in ROM of interphalangeal joints in donor and control fingers (pooled weighted mean difference: −12.10; 95% confidence interval: −28.59, 4.39; I2 = 81%, n = 6 studies). One-third of donor fingers had cold intolerance.

Conclusion There is no significant effect on ROM of donor finger. However, the impairment that seems to be in sensory recovery and aesthetic outcomes needs to be further evaluated objectively.
Sural Artery as a Recipient Vessel for Free Flaps
Authors: Panagatla Prakash , Ravula Parvathi , Chandrashekar Patnala , Srikanth R. , Alekya Nakka
Published: February 2023

Introduction The axial vessels like the anterior and posterior tibial emerge as the first choice of recipient vessels, in free flaps for lower limb trauma. When the defects are located more proximally in the leg, the deeper course of the axial vessels makes the dissection more tedious. Alternative vessels like the descending genicular, medial genicular, and distal end of the descending branch of the lateral circumflex femoral can be used for an end-to-end anastomosis, well away from the zone of trauma.

The objective of this study was to define the indications and technique of the use of the sural vessels as the recipient pedicle for proximal and middle third leg defects.

Patients and Methods For the period 2006 to 2022, 18 leg defects following road traffic accidents were covered with latissimus dorsi muscle flap using sural vessels as the recipient pedicle.

Results Among 18 patients, 8 patients had defect in proximal third, 8 had a combined defect in proximal and middle third leg, and 2 had defect in middle third leg. Two patients developed arterial thrombosis and one patient had venous thrombosis for which re-exploration was performed. Two flaps were lost and sixteen had successful wound coverage.

Conclusion The sural vessels as recipient pedicle are easier to access and can be considered as a reliable option for free flaps in limb defects of proximal and middle third leg. Using the submuscular part of the vessel ensures a better distal reach of the flap.
Patient-Reported Outcomes in Colorectal Surgery
Authors: Maspero Marianna , Hull Tracy
Published: February 2023

Given the increased life expectancy and improvements in the treatment of colorectal patients, the success of a treatment course can no longer be determined only by objective outcomes. Health care providers ought to take into consideration the impact an intervention will have on the quality of life of patients. Endpoints that take into account the patient's perspective are defined as patient-reported outcomes (PROs). PROs are assessed through patient-reported outcome measures (PROMs), usually in the form of questionnaires.

PROs are especially important in colorectal surgery, whose procedures can often be associated with some degree of postoperative functional impairment.

Several PROMs are available for colorectal surgery patients. However, while some scientific societies have offered recommendations, there is no standardization in the field and PROMs are seldom implemented in clinical practice. The routine use of validated PROMs can guarantee that functional outcomes are followed over time; this way, they can be addressed in case of worsening.

This review will provide an overview of the most commonly used PROMs in colorectal surgery, both generic and disease specific, as well as a summary of the available evidence in support of their routine utilization.
Influence of flanged-cutout on the buckling behaviors of square plate under uniaxial compression
Authors: Wang Wensheng , Ning Huijun , Wei Haojie , Mei Qun , Xu Longtao
Published: February 2023

Cutouts are commonly found in aerospace, ships, and marine structures, which have a great influence on mechanical properties such as stress concentration, natural frequency, and structural load-bearing performance of the structure. In this study, buckling behaviors of a square plate with a circular flanged cutout at the center are explored numerically, aiming to address the influence of different cutout parameters on the elastic and elasto-plastic buckling behaviors of the perforated plate. The flanged-perforated plate is subjected to uniaxial compressive loads, and the four edges are simply supported in the out-of-plane direction. The influence of various cutout parameters on the elastic and elasto-plastic buckling behaviors of the perforated plate is examined through a series of buckling analysis. In addition, structural weight reduction of the uniaxial compressed perforated square plates is carried out under the constraint of the elastic buckling stress of the plate structure. The findings indicate that different cutout parameters have a significant impact on the buckling performance of the plate. Perforated plates with flanging exhibit higher buckling strength than those without flanging, and variations in plate geometric parameters (such as the plate slenderness ratio and cutout radius ratio) are associated with increases in elastic buckling stress and elasto-plastic ultimate strength. The results of this paper can provide references for the design of flanged-cutouts in engineering.
Investigating the validity of the Bosanquet equation for predicting the self-diffusivities of fluids inside nanotubes using equilibrium molecular dynamics simulations
Authors: Chen Qu , Zhou Jianping
Published: February 2023

The self-diffusion of fluids in nanotubes generally consists of both molecule–molecule and molecule–wall interactions, which can be quantitatively described by the Knudsen mechanism and the molecular mechanism, respectively. Combining these two effects, the Bosanquet equation is generally used to predict the self-diffusivities of molecules in one-dimensional nanopores. In this work, equilibrium molecular dynamics simulations were employed to investigate the validity of the equation in predicting the self-diffusivities of fluids inside carbon, boron nitride, and silicon carbide nanotubes with diameters from ∼1.0 to 4.3 nm. Our results indicate that although the Bosanquet equation can predict the self-diffusivities of H2, Ar, CH4, CO2, C2H6, and C3H8 in carbon nanotubes in the same order of magnitude, the accuracy of these predictions is generally rather poor. At high and moderate loadings, the large deviation mainly results from the limited accuracy of the simplistic free path model, which tends to neglect the intermolecular forces of fluid molecules. However, at low loadings, the failure of the Bosanquet equation can be traced to the failure of the Knudsen model, which largely underestimates the diffusivity in nanotubes due to the smoothness of the tube wall. Furthermore, the Bosanquet equation fails to predict the self-diffusivities of H2O in confinement since the presence of hydrogen bonding violates the mean free path theory. It is suggested that further modification of this extrapolation should take into account the intermolecular forces of fluid molecules as well as the smoothness of the tube wall.
Analytical model for curved-shock Mach reflection
Authors: Shi Chongguang , You Yancheng , Zheng Xiaogang , Zhu Chengxiang
Published: February 2023

Mach reflection (MR) is an essential component in the development of the shock theory, as the incident shock curvature is found to have a significant effect on the MR patterns. Curved-shock Mach reflection (CMR) is not yet adequately understood due to the rotational complexity behind curved shocks. Here, CMR in steady, planar/axisymmetric flows is analyzed to supplement the well-studied phenomena caused by oblique-shock Mach reflection (OMR). The solution from the von Neumann's three-shock theory does not fully describe the CMR case. A CMR structure is presented and characterized by an incident shock, reflected shock, Mach stem, and expansion/compression waves over the slipline or occasionally an absence of waves due to pressure equilibrium. On the basis of this CMR structure, an analytical model for predicting the Mach stem in the CMR case is established. The model reduces to the OMR case if the shock curvature is not applicable. Predictions of the Mach stem geometry and shock structure based on the model exhibit better agreement with the numerical results than predictions using previous models. It is found that the circumferential shock curvature plays a key role in the axisymmetric doubly curved CMR case, which results in a different outcome from the planar case.
Magnetostriction property modeling of silicon steel considering stress-induced and magnetocrystalline anisotropy
Authors: Ben Tong , Kong Yuqi , Chen Long , Chen Fangyuan , Zhang Xian
Published: February 2023

This paper proposed an improved magnetostriction model for correlation of anisotropy in non-oriented (NO) silicon steel based on the free energy, which considers stress-induced and magnetocrystalline anisotropy. Firstly, the free energy model, which includes stress-induced anisotropy energy, the energy of magnetic field, and the anisotropic energy of magnetic crystals, is incorporated into the anhysteretic magnetization parameter Man. Then, to obtain the magnetic field and proposed model parameters related to stress-induced and magnetocrystalline anisotropy, the magnetostrictive strain loops at different magnetization directions of NO silicon steel are measured. Finally, based on the parameters obtained from experimental data of the proposed model, magnetostrictive strain loops under varying magnetization directions are simulated. This improved magnetostriction model can be applied to the calculation of the vector magnetostriction of the motor core.
Measurement of magnetic properties of grain-oriented electrical steel under bending stress in a wide frequency range
Authors: Chen Long , Yan Dongyang , Ben Tong , Jing Libing , Liu Qian
Published: February 2023

To clarify the mechanism of the magnetic properties deterioration and the increasing loss of the Grain-Oriented (GO) electrical steel wound cores under serving conditions, the effect of the bending stress in a wide frequency range should be thoroughly investigated. In this paper, a magnetic properties measuring system for GO electrical steel under different bending stress from 50 Hz to 1000 Hz is proposed. To ensure the accuracy and reproductivity of the measurements, the waveform of magnetic flux densities should be controlled to be sinusoidal. However, the bending stress aggravates the material’s nonlinear properties, making waveform control very difficult. To solve this problem, a frequency-domain adaptive dual-loop feedback control algorithm is developed. Obtained results show that the proposed method has a good effect on waveform control under bending stress, and the loss of the material under different magnetizing conditions is then analyzed.
Field-free switching model of spin–orbit torque (SOT)-MTJ device with thermal effect based on voltage-controlled magnetic anisotropy (VCMA)
Authors: Li Shaomin , Jiang Yanfeng
Published: February 2023

Electrically driven magnetization switch has attracted much attention in the new spintronic memory, especially for spin–orbit torque (SOT)-based magnetic random access memory (MRAM). However, the published models are facing limitations with the continuous shrinkage of the feature size down to nanoscale. Also, the thermal effect caused by switching operation is non-negligible. Therefore, an effective model is needed to represent the switching dynamic of the device concerning the influences of the nanoscale and the thermal effect. In the paper, a compact model of three-terminal SOT-driven switching is established. The influence of the voltage-controlled magnetic anisotropy (VCMA) and spin transfer torque (STT) effect induced by bias voltage on the field-free SOT-driven switching is considered by numerically solving the LLG equations. Furthermore, a 3D model of the SOT-MTJ device is established by finite element method to trace the thermoelectric behavior inside the device. The thermoelectric behavior is integrated into the compact model to show the influence of the temperature on the switching behavior, highlighting the importance of the thermal effect for the realistic modelling of SOT-driven switching. Finally, a novel voltage pulse scheme is proposed, which can effectively shorten the switching time and improve the reliability of the device. The established model could provide strategies and guidelines for next-generation memory design and application.
Thermal analysis and experimental verification of permanent magnet synchronous motor by combining lumped-parameter thermal networks with analytical method
Authors: Nguyen Manh-Dung , Woo Jong-Hyeon , Shin Hyo-Seob , Lee Young-Keun , Lee Hoon-Ki , Shin Kyung-Hun , Phung Anh-Tuan , Choi Jang-Young
Published: February 2023

This study presents an approach to calculating the temperature increase in the internal components of permanent magnet synchronous machines by applying lumped-parameter thermal networks and analytical methods. Accordingly, the thermal equivalent circuit method is employed to obtain the temperatures of the machine’s internal components. Furthermore, this analytical method predicts the temperature distribution in the slot area. The 24/6 prototype was used to evaluate the proposed model by comparing the calculated and finite element method simulation.
Is Australia’s lack of national clinical leadership hampering efforts with the oral health policy agenda?
Authors: Nguyen Tan Minh , Arora Amit , Sethi Sneha , Gavanescu Danielle Justine , Heredia Ruth , Scully Ben , Lin Clare , Hall Martin
Published: February 2023

The landmark 2021 Resolution on Oral Health by the 74th World Health Assembly has elevated the importance of oral health into the global health policy agenda. This has led to the development and adoption of the World Health Organization (WHO) Global Strategy on Oral Health in 2022. It acknowledged the need to integrate oral health as part of universal health coverage (UHC), which is supported by national clinical leadership for oral health. Although Australia is a signatory WHO member state, it is yet to appoint a Commonwealth Chief Dental Officer to provide national clinical leadership. This commentary provides a background on the current issues on population oral health in Australia, an insight into the Australian oral healthcare system, and explores some of the challenges and learnings related to previous Commonwealth dental programs. This paper highlights why expertise in dental public health is required to steer national oral health policy that is focused on prevention and early intervention. A population oral health approach for UHC should be informed by evidence, prioritise and address oral health inequities, and be co-ordinated by national clinical leadership for oral health.
Molecular and morphological analyses support recognition of Prostanthera volucris (Lamiaceae), a new species from the Central Tablelands of New South Wales
Authors: O’Donnell Ryan P. , Bruhl Jeremy J. , Telford Ian R. H. , Wilson Trevor C. , Zimmer Heidi C. , Taseski Guy M. , Andrew Rose L.
Published: February 2023

Research into the systematics of Prostanthera recently revealed close evolutionary relationship among P. phylicifolia sens. str., the critically endangered P. gilesii, and a population of uncertain identity from the Central Tablelands of New South Wales (NSW), Australia. Previous analyses were unable to establish whether genetic boundaries separated these taxa. This study assessed species boundaries among these three taxa by using a combination of single-nucleotide polymorphisms (SNPs) sampled at the population-scale and multivariate analysis of morphological characters. Ordination, model-based clustering, F-statistics, neighbour-network analysis, phylogenetic analysis, and ancestry coefficient estimates all provided support for discrete genetic differences among the three taxa. Morphological phenetic analysis recovered congruent morphological clusters and identified a suite of corresponding diagnostic characters. This congruence of molecular and morphological evidence supports the presence of three independently evolving lineages, two of which correspond with the previously described P. gilesii and P. phylicifolia sens. str. The third taxon, represented by a single population from the Central Tablelands of NSW, is here described as P. volucris R.P.O’Donnell. A detailed description, diagnostic line drawings and photographs are provided. We evaluate P. volucris as satisfying criteria to be considered Critically Endangered.
Effect of Ni content and crystallographic orientation on mechanical properties of single-crystal (CoCr)100-x
Ni
x
medium-entropy alloy
Authors: Zhang Can , Shi Mingxing
Published: February 2023

Nanoindentation analyses of (CoCr)100-x
Ni
x
medium-entropy alloys with different Ni contents and crystal orientations were carried out by molecular dynamics simulations. Analyses show that the force-displacement curves during elastic deformation are in good accordance with the Hertz contact theory and the elastic modulus is closely related to the Ni contents and crystal orientations. The elastic-plastic transition point appears later in (CoCr)67Ni33 than in other alloys. The plastic deformation was studied by exploring the instantaneous microstructure, which was found to be dominated by homogeneous nucleation of Shockley partial dislocations and the accumulation of stacking faults, and different levels of dislocation density were produced in the alloys with different Ni contents and crystal orientations. By analyzing the evolution of dislocation density and hardness, a linear relationship between the square root of dislocation density and hardness can be revealed, which agrees well with the classical Taylor hardening model, and the empirical constant is found closely related to crystal orientations.
Multilayer α′-4H-Borophene Growth on Gallium Arsenide towards High-Performance Near-Infrared Photodetector
Authors: Liang Xinchao , Hou Chuang , Wu Zenghui , Wu Zitong , Tai Guoan
Published: February 2023

Multilayer borophene was predicted to have a similar semiconductor property to its monolayer arise from the weak van der Waals interactions between the layers. Besides, multilayer borophene has a higher carrier mobility than monolayer ones, so it is placed great hopes in applications of photoelectric and photovoltaic devices. However, its preparation and application in experiments of multilayer borophene are still lacking. Here, multilayer α′-4H-borophene was synthesized on semiconducting n-type GaAs substrates using NaBH4 source as precursor and hydrogen as the carrier gas under controlled temperature and pressure conditions. The experimental results of the borophene are in good agreement with those of its theoretical prediction. The borophene is a semiconductor with a bandgap of 2.48 eV. To demonstrate the device application potential of the borophene, a near-infrared photodetector composed of p-type borophene and n-type GaAs was fabricated. The photodetector shows a high photoresponsivity of 0.31 mA•W-1, a high specific detectivity of 108 Jones, and a fast response or recovery speed of 117 or 109 ms under the irradiation with the wavelength of 940 nm at zero bias. The results prove that the α′-4H-borophene/GaAs photodetector can show high sensitivity and zero consumption, which is of great value in meeting the appeal of sustainable development of society.
Evaluation of auto-segmentation for brachytherapy of postoperative cervical cancer using deep learning-based workflow
Authors: Wang Jiahao , Chen Yuanyuan , Tu Yeqiang , Xie Hongling , Chen Yukai , Luo Lumeng , Zhou Pengfei , Tang Qiu
Published: February 2023

Objective. The purpose of this study was to evaluate the accuracy of brachytherapy (BT) planning structures derived from Deep learning (DL) based auto-segmentation compared with standard manual delineation for postoperative cervical cancer. Approach. We introduced a convolutional neural networks (CNN) which was developed and presented for auto-segmentation in cervical cancer radiotherapy. The dataset of 60 patients received BT of postoperative cervical cancer was used to train and test this model for delineation of high-risk clinical target volume (HRCTV) and organs at risk (OARs). Dice similarity coefficient (DSC), 95% Hausdorff distance (95%HD), Jaccard coefficient (JC) and dose-volume index (DVI) were used to evaluate the accuracy. The correlation between geometric metrics and dosimetric difference was performed by Spearman’s correlation analysis. The radiation oncologists scored the auto-segmented contours by rating the lever of satisfaction (no edits, minor edits, major edits). Main results. The mean DSC values of DL based model were 0.87, 0.94, 0.86, 0.79 and 0.92 for HRCTV, bladder, rectum, sigmoid and small intestine, respectively. The Bland-Altman test obtained dose agreement for HRCTV_D90%, HRCTV_Dmean, bladder_D2cc, sigmoid_D2cc and small intestine_D2cc. Wilcoxon’s signed-rank test indicated significant dosimetric differences in bladder_D0.1cc, rectum_D0.1cc and rectum_D2cc (P < 0.05). A strong correlation between HRCTV_D90% with its DSC (R = −0.842, P = 0.002) and JC (R = −0.818, P = 0.004) were found in Spearman’s correlation analysis. From the physician review, 80% of HRCTVs and 72.5% of OARs in the test dataset were shown satisfaction (no edits). Significance. The proposed DL based model achieved a satisfied agreement between the auto-segmented and manually defined contours of HRCTV and OARs, although the clinical acceptance of small volume dose of OARs around the target was a concern. DL based auto-segmentation was an essential component in cervical cancer workflow which would generate the accurate contouring.
The improvement of endurance characteristics in a superlattice-like material-based phase change device
Authors: Zheng Long , Wu Xiaoqing , Xue Jianzhong , Zhu Xiaoqin
Published: February 2023

Improvement of endurance characteristics has been a hot area of phase-change memoryresearch. The properties of a phase-change material are believed to play an important role in device endurance. Repeated SET–RESET operation always leads to material failure problems, such as composition deviation and phase separation. Moreover, the quality of the electrode and the electrode contact also determine the endurance characteristics. In this study, C nanolayers were periodically inserted into the phase-change material Ge2Sb2Te5 (GST) to fabricate a superlattice-like (SLL) structure. Although some of C bonded with some of the Ge, Sb and Te atoms, more C atoms prefer nanometer-scale clusters at the grain boundary in the SLL film. The typical local configuration of GST was unchanged when artificial C nanolayers were inserted. Transmission electron microscopy experiments revealed that the bonded C atoms and nanometer-scale C clusters may occupy the spontaneously created holes and defects, preventing composition deviation of the phase-change material and prolonging the electrode service life. The contact surface between the phase-change material and the electrode is also improved. As a result, we found that the endurance cycle could be improved by up to 106 for a GST/C SLL film-based device.
Higher-order sideband based on transparent windows in a two-cavity optomechanical system
Authors: Bao Ximin , Liu Linyang , Dai Ling , Kong Cui
Published: February 2023

We present a scheme to realize the regulation of single and double transparent windows in a two-cavity optomechanical device. By studying the output field through the two-cavity device, we not only show the transmission spectrum of the probe field and the second-order sideband process, but also analyze the physical mechanism of the induced transparency window and the efficiency of the second-order sideband process. Moreover, the optomechanically induced transparency window and the coupling of two cavities resulting in transparency window are discussed. We find that the transparency windows and the second-order sideband process can be modulated by the power of the control field and the coupling strength between two cavities. Our device is feasible for controlling light propagation, which might have potential application in quantum optical devices and quantum information networks.
Exploring ferroelectric properties of sol-gel lead zirconate titanate nano-crystalline thin films and ceramics by doping ytterbium for energy-storage application
Authors: Ibrahim F A , El-Desoky M M
Published: February 2023

This work concerns how ytterbium affects the ferroelectric characteristics of sol-gel Yb doped lead zirconate (PYZ) and lead zirconate titanate (PYZT) thin films and ceramics. Lead zirconate Pb(0.9) )-Yb0.01 Zr (0.09 (PYZ) and lead zirconate titanate Pb0.9-Yb0.01-Zr0.045-Ti0.045 (PYZT) doping with ytterbium thin films were prepared on a glass substrate using a sol-gel doctor blade coating technique at low temperature. The structure of the synthesized thin films and ceramic nanocrystals was examined using X-ray diffraction (XRD), transmission electron microscopy (TEM), and electron diffraction (ED). PYZ and PYZT ceramics had 11.8 nm and 30.65 nm respectively, whereas PYZ and PYZT thin films featured nanocrystals that were, respectively, 17.5 nm and 13.87 nm in size. Particle size was determined to be entirely consistent across the TEM and XRD data. Dielectric investigations showed that the dielectric constant was dropping for ceramic samples as compared to thin film samples. According to hysteresis loop estimates, the energy-storage density and efficiency for thin films and ceramics were average approximately 39.35 J cm−3 and 66.02 percent for (PYZ) and 71.33 J cm−3 and 70.91 percent for (PYZT), respectively. The results showed that the ferroelectric, dielectric, and structural properties of materials affected the ytterbium content. (PYZ) and (PYZT) thin films and ceramics may have a prospective use in energy storage devices.
Characterization of unidirectional and bidirectional transparencies in

PT

-symmetric quantum and classical systems
Authors: Lazo Edmundo , Humire Fernando R
Published: February 2023

We studied the scattering state behavior of tight-binding quantum system and classical electrical transmission lines. We distributed on-site energies ϵ

n
and resistances R

n
, respectively, according to a parity-time




-symmetric distribution. Using the formalism of scattering matrix S and transfer matrix M, we derived analytical expressions for components of transfer matrix M, and through them, we found transmission coefficient T and left (R

L
) and right (R

R
) reflectance. In addition, we found a generalized conservation relation that relates T, R

L
and R

R
, valid for quantum and classical




-symmetric systems. We numerically studied the general behavior of T, R

L
, R

R
and eigenvalues s
± of scattering matrix S in the full range of possible values of the gain and loss parameters. We observed the existence of unidirectional and bidirectional transparency for specific energies E (quantum case) and specific frequencies Ω (transmission line case), for which the following conditions were simultaneously fulfilled: i) T was unitary (T = 1), ii) eigenvalues s
± were degenerate and unimodular

s

±

=
1

, iii) the product of reflectances tended to zero,

R

L

R

R

→
0

, and iv) phases ϕ of one or both reflection amplitudes

ϕ

r

L

,

ϕ

r

R

showed abrupt change of π. This way, we characterized the unidirectional and bidirectional transparency for classical and quantum systems as a function of the gain and loss parameters that describe both models. In addition, the theoretical results showed complete agreement with the numerical calculation. We hope that our work contributes to a better understanding of the influence of the




-symmetric distribution of gain and loss parameters on the scattering properties of quantum and classical systems.
Research on fast forward kinematics of an offset-type flexible micro-motion Delta parallel mechanism
Authors: Li Xiang , Song Zhicheng , Zhang You , Wang Linkang , Yang Xiaolong , Wu Hongtao
Published: February 2023

In this paper, a fast numerical iterative algorithm is proposed based on the Pseudo-Rigid-Body-Model and geometric method to deal with the problem of the offset-type flexible Delta mechanism forward kinematics with multiple solutions and without analytical solutions. In forward kinematics, the quartic kinematic equations are reduced to quadratic ones by variable substitution. As the simplest nonlinear equations, quadratic equations can be represented by the coefficient matrices which is suitable for computer calculation. And due to the operational properties of the matrix, the updating and iterative process in the steps of Newton’s method can be simplified and improved to solve the forward kinematics more efficiently. The convergence and singularity of the proposed iterative algorithm are also analysed. By controlling the offset-type flexible micro-motion Delta parallel mechanism to move along three different expected spatial trace curves and measuring the displacements, the experiment results show that the Root Mean Square Error between the measured values and the expected values of linear positioning is 0.9177 μm for 37.4166 μm. Moreover, it is proved by numerical examples that the proposed iterative algorithm takes only 0.53 ms on average to solve the forward kinematic problems. The calculation time is reduced by 90.3% on average compared to the traditional Newton’s method, which provides a feasible solution for real-time control based on forward kinematics.
Dipolar effects on the work function of an alkali-iodide overlayer (XI, X = Li, Na, K, Rb, and Cs) on tungsten surfaces
Authors: Diaz L , Albers R C , Saxena A , Sanati M
Published: February 2023

A first-principles approach was used to investigate the effects of alkali metal iodide XI (X = Li, Na, K, Rb, and Cs) adsorption on the work functions of (100), (110), and (111) surfaces of W. For the most energetically stable structures, work functions and their corresponding electric dipole moment vectors were calculated. In agreement with available experimental measurements, it was verified that the formation of XI dipoles on the W surface causes the work function to decrease significantly. It was shown that the calculated XI dipoles are tilted with respect to the W surface for all systems. This contradicts earlier published suggestions that the surface electrostatic energy of the dipoles prevented them from being aligned along the surface and were instead normal to the surface. In our work it is shown that the orientations (tilt) and strengths of the dipole moments can be explained in terms of the internal strain caused by the alkali metal’s different atomic sizes and available surface area. What matters for the decrease in the work function is the component of the dipolar moment perpendicular to the surface. For all systems, the work function reduction was shown to be directly proportional to the normal component of the electric field created by these XI dipoles.
Study on vanadium dioxide based terahertz metamaterials with switchable functions from five-band absorption to triple-band plasmon-induced transparency
Authors: Lin Hongyan , Zou Yuke , Wu Yangkuan , Xiahou Xiuwen , Zhu Huaxin , Zhang Xiangyang , Wang Ben-Xin
Published: February 2023

A bifunctional switchable terahertz metamaterial utilizing vanadium dioxide (VO2) able to dynamically convert from multiband absorption to multiband plasmon-induced transparency (PIT) is designed, which is consisted of four different-sized metallic split rings placed on a dielectric slab backed by a continuous VO2 film. Based on unique insulator-metal phase transition properties of VO2, the present functions of designed structural could be realized by changing the temperature of VO2. When the VO2 is in the conducting phase, it possesses five discrete absorption peaks with the frequencies of 1.30 THz, 1.48 Hz, 2.07 THz, 2.46 THz and 2.72 THz with average absorbance greater than 98.0%. When the VO2 is in the insulating phase, it exhibits three obvious PIT peaks, the transmittances of them are 79.5%, 95.3% and 99.7% at the frequencies of 1.57 THz, 1.75 THz and 2.09 THz, respectively. Effects of geometric parameters on absorption and transparency are investigated. Results revealed that the dimension changes of surface patterned arrays show an important role in controlling resonance responses of absorption and transparency behavior. The switchable VO2-based metamaterial could have great potential applications in the fields of smart absorption, terahertz optical switches, filters, and slow-light devices.
Deducing neutron star equation of state parameters directly from telescope spectra with uncertainty-aware machine learning
Authors: Farrell Delaney , Baldi Pierre , Ott Jordan , Ghosh Aishik , Steiner Andrew W. , Kavitkar Atharva , Lindblom Lee , Whiteson Daniel , Weber Fridolin
Published: February 2023

Neutron stars provide a unique laboratory for studying matter at extreme pressures and densities. While there is no direct way to explore their interior structure, X-rays emitted from these stars can indirectly provide clues to the equation of state (EOS) of the superdense nuclear matter through the inference of the star's mass and radius. However, inference of EOS directly from a star's X-ray spectra is extremely challenging and is complicated by systematic uncertainties. The current state of the art is to use simulation-based likelihoods in a piece-wise method which relies on certain theoretical assumptions and simplifications about the uncertainties. It first infers the star's mass and radius to reduce the dimensionality of the problem, and from those quantities infer the EOS. We demonstrate a series of enhancements to the state of the art, in terms of realistic uncertainty quantification and a path towards circumventing the need for theoretical assumptions to infer physical properties with machine learning. We also demonstrate novel inference of the EOS directly from the high-dimensional spectra of observed stars, avoiding the intermediate mass-radius step. Our network is conditioned on the sources of uncertainty of each star, allowing for natural and complete propagation of uncertainties to the EOS.
Modeling strangeness enhancements to resolve the muon excess in cosmic ray extensive air shower data
Authors: Manshanden Julien , Sigl Günter , Garzelli Maria V.
Published: February 2023

Experimental observations of extensive air showers have revealed an excess of the muon
content with respect to their theoretical simulations, which we refer to as the muon puzzle. This
muon puzzle hampers a precise determination of the ultra-high-energy cosmic ray mass
composition. We investigate the potential of producing states of dense quark-gluon matter (which
we call fireballs) to resolve the muon puzzle as quantified with data from the Pierre Auger
Observatory on the depth of the shower maximum and the number of muons at ground. Adopting a
phenomenological fireball model, we find that the inelasticity enhancement associated with the
formation of a plasma state is in tension with data on the electromagnetic longitudinal shower
development. Instead, we restrict the fireball model to only enhance the strangeness produced in
Standard Model hadronic interactions, and dub this model the strangeball model. With
an analytic approach based on the Heitler-Matthews model we then find explicit sets of
strangeball parameters that resolve the muon puzzle. Constraints from data on
shower-to-shower fluctuations of the muon number require strangeness enhancements already at
energies accessible to current-generation collider experiments. At Tevatron and LHC energies we
estimate 40% of the interactions to produce strangeballs, corresponding to a 5–9%
increase of the average fraction of energy retained in the hadronic cascade compared
to predictions from current hadronic interaction models. A comparison with relevant measurements
of the LHCf and LHCb detectors does not directly exclude this scenario, though the
obtained tension with LHCb suggests a stringent test at 14 TeV.
The Beaming Effect for Fermi-LAT-detected FR-I Radio Galaxies
Authors: Ye Xu-Hong , Zeng Xiang-Tao , Huang Dan-Yi , Zhang Zhuang , Pei Zhi-Yuan , Fan Jun-Hui
Published: February 2023

Our knowledge of Giga-electron volt (GeV) radio galaxies has been revolutionized by the Fermi-LAT Telescope, which provides an excellent opportunity to study the physical properties of GeV radio galaxies. According to the radio power and morphology, radio galaxies can be separated into Fanaroff–Riley Type I radio galaxies (FR-Is) and Type II radio galaxies (FR-IIs). In this paper, we consider the unification of FR-Is and BL Lacertae objects (BL Lacs), and assume FR-Is to be a standard candle to discuss the beaming effect for Fermi-LAT-detected FR-Is. Our main conclusions are as follows: (1) The estimated Doppler factors for 30 Fermi-LAT-detected FR-Is are in a range of δ
I = 0.88 − 7.49. The average Doppler factor (〈δ
I〉 = 2.56 ± 0.30) of the 30 FR-Is is smaller than that (〈δ
BL〉 = 10.28 ± 2.03) of the 126 Fermi-LAT-detected BL Lacs, supporting the unification model that FR-Is are regarded as the misaligned BL Lacs with smaller Doppler factors; (2) We propose that different regions of FR-Is in the plot of the γ-ray luminosity against the photon spectral index

(
log

L

γ

–

α

ph

)

may indicate the different beaming effects; (3) The average Doppler factor of the 6 TeV FR-Is is similar to that of the 24 non-TeV FR-Is, which implies that the difference between the TeV and GeV emissions is not driven by the beaming effect in the Fermi-LAT-detected FR-I samples.
Strong spin frustration and magnetism in kagomé antiferromagnets LnCu3(OH)6Br3 (Ln = Nd, Sm, and Eu)
Authors: Zhong Jin-Qun , Yu Zhen-Wei , Yue Xiao-Yu , Wang Yi-Yan , Liang Hui , Sun Yan , Wu Dan-Dan , Ding Zong-Ling , Sun Jin , Sun Xue-Feng , Li Qiu-Ju
Published: February 2023

To study the effects of lanthanide ions on the geometrically frustrated antiferromagnets and their magnetic properties, we grew high-quality single crystals of LnCu3(OH)6Br3 (Ln = Nd, Sm, and Eu) by hydrothermal method and studied their crystal structures and magnetic properties. The refinements of the crystal structure referred to the powder x-ray diffraction data show that LnCu3(OH)6Br3 adopt a Kapellasite-type layer structure, which is isostructural to their chlorine analogue. Magnetic susceptibilities demonstrate that LnCu3(OH)6Br3 have strong antiferromagnetic coupling and a pronounced magnetic frustration effect. Magnetization measurements indicate canted antiferromagnetic ordering of Cu2+ ions around 16 K within the kagomé plane and weak ferromagnetic coupling. Moreover, shoulder-like anomalies in specific heat around 16 K could be a signature of emergent of magnetic ordering. The low-temperature negative magnetization and specific heat of LnCu3(OH)6Br3 (Ln = Nd, Sm, and Eu) indicate that Ln
3+ ions induce more exotic magnetic ground state properties.
Topological magnetotransport and electrical switching of sputtered antiferromagnetic Ir20Mn80
Authors: Xiong Danrong , Jiang Yuhao , Zhu Daoqian , Du Ao , Guo Zongxia , Lu Shiyang , Wang Chunxu , Xia Qingtao , Zhu Dapeng , Zhao Weisheng
Published: February 2023

Topological magnetotransport in non-collinear antiferromagnets has attracted extensive attention due to the exotic phenomena such as large anomalous Hall effect (AHE), magnetic spin Hall effect, and chiral anomaly. The materials exhibiting topological antiferromagnetic physics are typically limited in special Mn3
X family such as Mn3Sn and Mn3Ge. Exploring the topological magnetotransport in common antiferromagnetic materials widely used in spintronics will not only enrich the platforms for investigating the non-collinear antiferromagnetic physics, but also have great importance for driving the nontrivial topological properties towards practical applications. Here, we report remarkable AHE, anisotropic and negative parallel magnetoresistance in the magnetron-sputtered Ir20Mn80 antiferromagnet, which is one of the most widely used antiferromagnetic materials in industrial spintronics. The ab initio calculations suggest that the Ir4Mn16 (IrMn4) or Mn3Ir nanocrystals hold nontrivial electronic band structures, which may contribute to the observed intriguing magnetotransport properties in the Ir20Mn80. Further, we demonstrate the spin–orbit torque switching of the antiferromagnetic Ir20Mn80 by the spin Hall current of Pt. The presented results highlight a great potential of the magnetron-sputtered Ir20Mn80 film for exploring the topological antiferromagnet-based physics and spintronics applications.
A 54-fs diode-pumped Kerr-lens mode-locked Yb:LuYSiO5 laser
Authors: Yu Yang , Chen Yuehang , Tian Wenlong , Zheng Li , Wang Geyang , Bai Chuan , Tian Xuan , Mai Haijing , Su Yulong , Zhu Jiangfeng , Wei Zhiyi
Published: February 2023

We demonstrate a Kerr-lens mode-locked Yb:LuYSiO5 (Yb:LYSO) laser with the pulse duration of 54 fs, corresponding to a spectral bandwidth of 25 nm centered at 1062 nm. To the best of our knowledge, this is the shortest pulse duration obtained from Yb:LYSO laser. At the repetition rate of 378.3 MHz, an output power of 111.6 mW is obtained using an output coupler with 0.6% transmittance, which can maintain long-time stable mode-locking more than 13 h.
First-principles study of the bandgap renormalization and optical property of β-LiGaO2
Authors: Fang Dangqi
Published: February 2023

The β-LiGaO2 with an orthorhombic wurtzite-derived structure is a candidate ultrawide direct-bandgap semiconductor. In this work, using the non-adiabatic Allen–Heine–Cardona approach, we investigate the bandgap renormalization arising from electron–phonon coupling. We find a sizable zero-point motion correction of –0.362 eV to the gap at Γ, which is dominated by the contributions of long-wavelength longitudinal optical phonons. The bandgap of β-LiGaO2 decreases monotonically with increasing temperature. We investigate the optical spectra by comparing the model Bethe–Salpether equation method with the independent-particle approximation. The calculated optical spectra including electron–hole interactions exhibit strong excitonic effects, in qualitative agreement with the experiment. The contributing interband transitions and the binding energy for the excitonic states are analyzed.
Synchronization coexistence in a Rulkov neural network based on locally active discrete memristor
Authors: Ma Ming-Lin , Xie Xiao-Hua , Yang Yang , Li Zhi-Jun , Sun Yi-Chuang
Published: February 2023

At present, many neuron models have been proposed, which can be divided into discrete neuron models and continuous neuron models. Discrete neuron models have the advantage of faster simulation speed and the ease of understanding complex dynamic phenomena. Due to the properties of memorability, nonvolatility, and local activity, locally active discrete memristors (LADMs) are also suitable for simulating synapses. In this paper, we use an LADM to mimic synapses and establish a Rulkov neural network model. It is found that the change of coupling strength and the initial state of the LADM leads to multiple firing patterns of the neural network. In addition, considering the influence of neural network parameters and the initial state of the LADM, numerical analysis methods such as phase diagram and timing diagram are used to study the phase synchronization. As the system parameters and the initial states of the LADM change, the LADM coupled Rulkov neural network exhibits synchronization transition and synchronization coexistence.
AG-GATCN: A novel method for predicting essential proteins
Authors: Yang Peishi , Lu Pengli , Zhang Teng
Published: February 2023

Essential proteins play an important role in disease diagnosis and drug development. Many methods have been devoted to the essential protein prediction by using some kinds of biological information. However, they either ignore the noise presented in the biological information itself or the noise generated during feature extraction. To overcome these problems, in this paper, we propose a novel method for predicting essential proteins called attention gate-graph attention network and temporal convolutional network (AG-GATCN). In AG-GATCN method, we use improved temporal convolutional network (TCN) to extract features from gene expression sequence. To address the noise in the gene expression sequence itself and the noise generated after the dilated causal convolution, we introduce attention mechanism and gating mechanism in TCN. In addition, we use graph attention network (GAT) to extract protein–protein interaction (PPI) network features, in which we construct the feature matrix by introducing node2vec technique and 7 centrality metrics, and to solve the GAT oversmoothing problem, we introduce gated tanh unit (GTU) in GAT. Finally, two types of features are integrated by us to predict essential proteins. Compared with the existing methods for predicting essential proteins, the experimental results show that AG-GATCN achieves better performance.
Mathematical Model for Flow of High-pressure Gas in Microscale
Authors: Chang Jin , Hu Zhiming , Liu Huaxun , Duan Xianggang , Xu Ke
Published: February 2023

Fused silica micro-tubes, whose size is similar to the pore throat in a low permeability reservoir, simplify the complex and tortuous of channels and throats and are used in this study to stimulate the flow pattern with micro-scale methods. A high-pressure micro-tube holder (designed and developed independently with a patent for invention) has been used to study gas flow patterns within the pressure range of 0.1MPa-30MPa. Moreover, we establish a gas flow equation and analysis the applicability of different inlet pressure based on the experiment result. The result shows: First, the pressure drop in the micro-tube is predominantly induced by friction resistance at low inlet pressure. While under relatively high inlet pressure, the impact of kinetic energy conversion and throttling effect on pressure drop shall be considered. Second, we build up a gas-flow equation in a micro-tube considering friction resistance, kinetic energy loss, and throttling effect. We also analyze the applicability for different diameters and inlet pressure. These research achievements were enriched in microtubule flow; different conditions have been identified for a different equation which has significant meaning to gas flow regulation in tight sandstorm reservoirs.