bluuebunny/crossref_metadata_2025 huggingface dataset:
Concomitant Transatrial and Transapical CRT-D Lead Implantation in a Patient with Chest Burn Injury
Authors: Riba Adam , Rashed Aref , Toth Roland , Tahin Tamas
Published: November 2022

Cardiac resynchronization therapy device with defibrillator (CRT-D) implantation is indicated for patients with a history of malignant ventricular arrhythmias, symptomatic heart failure, wide QRS, or high-degree atrioventricular block. A 67-year-old patient with dilated cardiomyopathy received a CRT-D with the conventional method but 1 month later skin necrosis was diagnosed above the device. The complete system was extracted from the patient and we utilized negative pressure wound therapy for the treatment of the remaining tissue. We decided to perform surgical reimplantation of the device using minithoracotomy: right atrial and right ventricular leads were introduced through the right atrial appendage and the left ventricular lead was inserted transapically. The device was implanted under the less scabby abdominal skin. We successfully applied the combination of transatrial and transapical lead placement, which has not been reported in the literature yet. It serves as an alternative method if the standard approach is not feasible.
Spontaneous Recurrent Pneumothorax during Pregnancy Secondary to Ectopic Deciduosis
Authors: Hakimi Ali A. , Sellers Morgan M. , Morton Alexander P.
Published: November 2022

Background Ectopic deciduosis is a benign presence of endometrial tissue outside of the uterus during pregnancy that rarely presents with pleuropulmonary manifestations and recurrent pneumothorax.

Case Description We report a 35-year-old woman at 15 weeks' gestation with a history of recurrent intrapartum right pneumothorax found to have pleural, pulmonary, and diaphragmatic lesions and a middle lobe air leak. Wedge resection of the middle lobe and mechanical pleurodesis was performed. Histopathological analysis was progesterone receptor and PAX8 positive consistent with ectopic deciduosis.

Conclusion Ectopic deciduosis is a rare cause of recurrent pneumothorax in pregnancy and should be considered when evaluating these patients.
A hybrid coded-aperture and Compton camera based on cerium-doped Gd3Al2Ga3O12 scintillators coupled with multi-pixel photon counter arrays
Authors: Kong Lingqin , Shuai Lei , Liang Xiuzuo , Li Daowu , Zhang Jipeng , Zhou Wei , Yang Yao , Wang Xiaoming , Hu Xuanhou , Li Chunmiao , Yu Yue , Ding Yi , Meng Fanhui , Zhang Yiwen , Wei Long
Published: November 2022

In this study, we propose a hybrid coded-aperture and Compton camera based on cerium-doped Gd3Al2Ga3O12 (GAGG:Ce) scintillator arrays coupled with Multi-Pixel Photon Counter (MPPC) arrays. The sensitive detector of the gamma camera consists of a single GAGG:Ce crystal coupled with a single-chip MPPC unit module. An impedance bridge circuit and a 64-channel data acquisition system were employed to record the code-aperture events and Compton coincidence events. After the calibration of position and energy, the total energy resolution for 662 keV gamma-rays from 137Cs was 6.6%. The hybrid camera had the characteristics of mechanical collimation and electronic collimation at the same time. In the code aperture mode, the reconstructed images were obtained by direct deconvolution and maximum likelihood expectation maximization (MLEM) methods. In the Compton imaging mode, the energy-dependent method was applied to order the sequence of Compton scatter events. The simple back-projection algorithm and list-mode MLEM algorithm were adopted for image reconstruction. Practical performances demonstrated that the angular resolutions in two modes were measured as 5.2° and 11.4°, respectively. In addition, the hybrid camera had a desirable imaging capability in a wide energy range (32 keV–2.6 MeV) and a wide field of view (∼210° in the horizontal direction). As for the sensitivity, the camera had a commercially available sensitivity level of localizing a 137Cs point source, producing ∼0.026 µSv/h in 5 min. Furthermore, the function of distinction for different radiation sources was preliminarily realized.
2nd and 3rd order spectral energy corrections with penumbral de-blurring methodology for opacity platform used on the National Ignition Facility
Authors: Dutra E. C. , Emig J. , Fontes C. J. , Heeter R. F. , Opachich Y. P. , Robey H. F. , Wallace M. S. , Perry T. S.
Published: November 2022

The Opacity Spectrometer (OpSpec) used in the National Ignition Facility’s opacity experiments measures x-ray spectra from 0.9 to 2.1 keV from the different experimental regions: the backlight source, emission source, and the absorption region with the transmission calculated from these regions. The OpSpec designs have gone through several iterations to help improve the signal-to-noise ratio, remove alternate crystal plane reflections, and improve spectral resolution, which helps to increase the validity of the opacity measurements. However, the source spans well outside the current working spectral range, and higher-order reflections are intrinsic to the crystal, which increases the overall signal seen in the data regions. The recorded data are the convolution of 1st order transmission, higher-order reflections, and the penumbra blurring. This work represents the details for deconvolving the 2nd and 3rd order spectral energy corrections with a penumbral de-blurring to correct the relative measurement of x-ray intensity of different spectral energies and further analysis of datasets relevant to the opacity experiments.
Nanoscale thermometry under ambient conditions via scanning thermal microscopy with 3D scanning differential method
Authors: Sun Lin , Wang Weihua , Jiang Peng , Bao Xinhe
Published: November 2022

Local temperature measurement with high resolution and accuracy is a key challenge in nowadays science and technologies at nanoscale. Quantitative characterization on temperature with sub-100 nm resolution is of significance for understanding the physical mechanisms of phonon transport and energy dissipation in nanoelectronics, optoelectronics, and thermoelectric devices. Scanning thermal microscopy (SThM) has been proved to be a versatile method for nanoscale thermometry. In particular, 2D profiling of the temperature field on the order of 10 nm and 10 mK has already been achieved by SThM with modulation techniques in ultrahigh vacuum to exclude the parasitic heat flow between air and the cantilever. However, few attempts have been made to truly realize 2D profiling of temperature quantitatively under ambient conditions, which is more relevant to realistic applications. Here, a 3D scanning differential method is developed to map the 2D temperature field of an operating nanodevice under ambient environment. Our method suppresses the thermal drift and the parasitic heat flow between air and the cantilever by consecutively measuring the temperatures in thermal contact and nonthermal contact scenarios rather than in a double-scan manner. The local 2D temperature field of a self-heating metal line with current crowding by a narrowing channel is mapped quantitatively by a sectional calibration with a statistic null-point method and a pixel-by-pixel correction with iterative calculation. Furthermore, we propose a figure of merit to evaluate the performance of thermocouple probes on temperature field profiling. The development of nanoscale thermometry under ambient environment would facilitate thermal manipulation on nanomaterials and nanodevices under practical conditions.
Cross-beam energy transfer between spatially smoothed laser beams
Authors: Oudin A. , Debayle A. , Ruyer C. , Benisti D.
Published: November 2022

The crossing of two spatially smoothed laser beams amounts to the crossings of a large number of speckles. The energy transfer between two of these speckles is mediated by laser induced electron/ion density ripples that act as a Bragg grating. In a weakly Landau-damped plasma, this ion acoustic wave (IAW) may propagate from one crossing region to another, hence perturbing the local electron/ion grating [Oudin et al. Phys. Rev. Lett. 127, 265001 (2021)] even without phase shift between IAWs. In this paper, we investigate how the phase-shifted IAWs generated at the speckle scale interfere and affect the overall energy exchange. To this aim, we perform 2D particle-in-cell simulations with in-phase and out-of-phase Gaussian beams. In the latter situation, which better matches a smoothed laser beam, we find that the destructive interferences between the ion waves significantly reduce the energy exchange compared to the plane wave case. Additional 2D particle-in-cell simulations with random phase plate smoothed laser beams confirm the relevance of this effect in carbon plasma. A second effect is that cross-beam energy transfer (CBET) inhibition persists in strongly damped plasmas when the speckle radius is comparable with the IAW damping distance. There, the reduction in the IAW amplitude is attributed to the smallness of the speckle's envelop. These results are supported by a simple model that analytically estimates the CBET and clearly shows that neglecting the inhomogeneities in the laser intensity would usually lead to an overestimate of the energy exchange.
A mobile setup for simultaneous and in situ neutron reflectivity, infrared spectroscopy, and ellipsometry studies
Authors: Busch Christian , Nagy Béla , Stöcklin Andreas , Gutfreund Philipp , Dahint Reiner , Ederth Thomas
Published: November 2022

Neutron reflectivity at the solid/liquid interface offers unique opportunities for resolving the structure–function relationships of interfacial layers in soft matter science. It is a non-destructive technique for detailed analysis of layered structures on molecular length scales, providing thickness, density, roughness, and composition of individual layers or components of adsorbed films. However, there are also some well-known limitations of this method, such as the lack of chemical information, the difficulties in determining large layer thicknesses, and the limited time resolution. We have addressed these shortcomings by designing and implementing a portable sample environment for in situ characterization at neutron reflectometry beamlines, integrating infrared spectroscopy under attenuated total reflection for determination of molecular entities and their conformation, and spectroscopic ellipsometry for rapid and independent measurement of layer thicknesses and refractive indices. The utility of this combined setup is demonstrated by two projects investigating (a) pH-dependent swelling of polyelectrolyte layers and (b) the impact of nanoparticles on lipid membranes to identify potential mechanisms of nanotoxicity.
Cargo transportation using an active polymer
Authors: Jain Namita , Thakur Snigdha
Published: November 2022

One of the fundamental goals of bioinspired synthetic systems is to achieve enhanced and controlled transport. Here, we demonstrate the transport of a colloidal cargo with an active filamentous engine. We explore the efficiency of the directional transport of the colloidal cargo by attaching it either at the front (pushing) or at the back (pulling) of the filament. The filament is chemo-mechanically active and acquires the activity by attaching chemically active beads that provide local tangential force along the chain. The effect of the size and location of the load, activity, and bending rigidity is comprehensively explored. We observe a transition from directional to rotational motion for the pushing load filament, whereas no such transition is observed for the filament pulling the load. The transition between different states is characterized using structural properties, such as the radius of gyration, order parameter, and tangent–tangent correlation. With the help of dynamical properties, we show that the modes of propulsion and their efficiency is different for pushing and pulling, which depend on the load size.
Reversible canted persistent spin textures in two-dimensional ferroelectric bilayer WTe2
Authors: Absor Moh. Adhib Ulil , Santoso Iman
Published: November 2022

The recent discovery of materials hosting persistent spin texture (PST) opens an avenue for the realization of energy-saving spintronics since they support an extraordinarily long spin lifetime. However, the stability of the PST is sensitively affected by symmetry breaking of the crystal induced by external perturbation such as the electric field. In this paper, through first-principles calculations supplemented by symmetry analysis, we report the emergence of the robust and stable PST with large spin splitting in the two-dimensional (2D) ferroelectric bilayer WTe2. Due to the low symmetry of the crystal (Cs point group), we observe a canted PST in the spin-split bands around the Fermi level displaying a unidirectional spin configuration tilted along the yz plane in the first Brillouin zone. Such a typical PST can be effectively reversed by out-of-plane ferroelectric switching induced by interlayer sliding along the in-plane direction. We further demonstrated that the reversible PST is realized by the application of an out-of-plane external electric field. Thus, our findings uncover the possibility of an electrically tunable PST in 2D materials, offering a promising platform for highly efficient and non-volatile spintronic devices.
Prediction and optimization of airfoil aerodynamic performance using deep neural network coupled Bayesian method
Authors: Liu Ruo-Lin , Hua Yue , Zhou Zhi-Fu , Li Yubai , Wu Wei-Tao , Aubry Nadine
Published: November 2022

In this paper, we proposed an innovative Bayesian optimization (BO) coupled with deep learning for rapid airfoil shape optimization to maximize aerodynamic performance of airfoils. The proposed aerodynamic coefficient prediction model (ACPM) consists of a convolutional path and a fully connected path, which enables the reconstruction of the end-to-end mapping between the Hicks–Henne (H–H) parameterized geometry and the aerodynamic coefficients of an airfoil. The computational fluid dynamics (CFD) model is first validated with the data in the literature, and the numerically simulated lift and drag coefficients were set as the ground truth to guide the model training and validate the network model based ACPM. The average accuracy of lift and drag coefficient predictions are both about 99%, and the determination coefficient R2 are more than 0.9970 and 0.9539, respectively. Coupled with the proposed ACPM, instead of the conventional expensive CFD simulator, the Bayesian method improved the ratio of lift and drag coefficients by more than 43%, where the optimized shape parameters of the airfoil coincide well with the results by the CFD. Furthermore, the whole optimization time is less than 2 min, two orders faster than the traditional BO-CFD framework. The obtained results demonstrate the great potential of the BO-ACPM framework in fast and accurate airfoil shape optimization and design.
Using polycyclic aromatic hydrocarbons for graphene growth on Cu(111) under ultra-high vacuum
Authors: Klein Benedikt P. , Stoodley Matthew A. , Edmondson Matthew , Rochford Luke A. , Walker Marc , Sattler Lars , Weber Sebastian M. , Hilt Gerhard , Williams Leon B. S. , Lee Tien-Lin , Saywell Alex , Maurer Reinhard J. , Duncan David A.
Published: November 2022

Ultra-high vacuum deposition of the polycyclic aromatic hydrocarbons azupyrene and pyrene onto a Cu(111) surface held at a temperature of 1000 K is herein shown to result in the formation of graphene. The presence of graphene was proven using scanning tunneling microscopy, x-ray photoelectron spectroscopy, angle-resolved photoemission spectroscopy, Raman spectroscopy, and low energy electron diffraction. The precursors, azupyrene and pyrene, are comparatively large aromatic molecules in contrast to more commonly employed precursors like methane or ethylene. While the formation of the hexagonal graphene lattice could naively be expected when pyrene is used as a precursor, the situation is more complex for azupyrene. In this case, the non-alternant topology of azupyrene with only 5- and 7-membered rings must be altered to form the observed hexagonal graphene lattice. Such a rearrangement, converting a non-alternant topology into an alternant one, is in line with previous reports describing similar topological alterations, including the isomerization of molecular azupyrene to pyrene. The thermal synthesis route to graphene, presented here, is achievable at comparatively low temperatures and under ultra-high vacuum conditions, which may enable further investigations of the growth process in a strictly controlled and clean environment that is not accessible with traditional precursors.
Hybrid magnonic-oscillator system
Authors: Hamadeh A. , Breitbach D. , Ender M. , Koujok A. , Mohseni M. , Kohl F. , Maskill J. , Bechberger M. , Pirro P.
Published: November 2022

We propose a hybrid magnonic-oscillator system based on the combination of a spin transfer auto-oscillator and a magnonic waveguide to open new perspectives for spin-wave based circuits. The system is composed of a spin transfer oscillator based on a vortex state which is dipolarly coupled to a nanoscale spin-wave waveguide with longitudinal magnetization. In its auto-oscillating regime, the oscillator emits coherent spin waves with tunable and controllable frequencies, directions, and amplitudes into the waveguide. We demonstrate the principle of this method using micromagnetic simulations and show that reconfiguration of the system is possible by changing the chirality and polarity of the magnetic vortex. Spin waves are emitted into the waveguide with high non-reciprocity and the preferred direction depends on the core polarity of the vortex. In contrast, different vortex chiralities lead to different amplitudes of the emitted waves. Our findings open up a novel way to design an agile spintronic device for the coherent and tunable generation of propagating spin waves.
Transit-time resonances enabling amplification and generation of terahertz radiation in periodic graphene p-i-n structures with the Zener–Klein interband tunneling
Authors: Ryzhii V. , Ryzhii M. , Mitin V. , Shur M. S. , Otsuji T.
Published: November 2022

The Zener–Klein (ZK) interband tunneling in graphene layers (GLs) with the lateral n-i-n and p-i-n junctions results in the specific characteristics that can be used for the rectification, detection, amplification, and generation of the terahertz (THz) signals. The transit-time delay of the tunneling electrons and holes in the depletion regions leads to the phase shift between the THz current and THz voltage causing the negative dynamic conductance in a certain frequency range and resulting in the so-called transit-time (TT) instability. The combination of the ZK tunneling and the TT negative dynamic conductance enables resonant THz the amplification and generation of THz radiation. We propose the THz devices based on periodic cascade GL p-i-n structures exhibiting the TT resonances and evaluate their potential performance. Such structures can serve as THz amplifiers and, being placed in a Fabry–Pérot cavity, or coupled to a THz antenna or using a ring oscillator connection, as THz radiation sources.
Ultrafast inverse design of quantum dot optical spectra via a joint TD-DFT learning scheme and deep reinforcement learning
Authors: Yoshida Hibiki , Sakamoto Katsuyoshi , Miyashita Naoya , Yamaguchi Koichi , Shen Qing , Okada Yoshitaka , Sogabe Tomah
Published: November 2022

Here, we report a case study on inverse design of quantum dot optical spectra using a deep reinforcement learning algorithm for the desired target optical property of semiconductor CdxSeyTex−y quantum dots. Machine learning models were trained to predict the optical absorption and emission spectra by using the training dataset by time dependent density functional theory simulation. We show that the trained deep deterministic policy gradient inverse design agent can infer the molecular structure with an accuracy of less than 1 Å at a fixed computational time of milliseconds and up to 100–1000 times faster than the conventional heuristic particle swam optimization method. Most of the effective inverse design problems based on the surrogate machine learning and reinforcement learning model have been focused on the field of nano-photonics. Few attempts have been made in the field of quantum optical system in a similar manner. For the first time, our results, to our knowledge, provide concrete evidence that for computationally challenging tasks, a well-trained deep reinforcement learning agent can replace the existing quantum simulation and heuristics optimization tool, enabling fast and scalable simulations of the optical property of nanometer sized semiconductor quantum dots.
A study on the performance of the cavitating flow structure and load characteristics of the vehicle launched underwater
Authors: Gao Shan , Shi Yao , Pan Guang , Quan Xiaobo
Published: November 2022

This paper analyzes cavitating flow structure and load characteristics of vehicles launched underwater for different cavitation numbers and different angles of attack. The improved delayed detached-eddy simulation model and volume of fluid, as well as overlapping mesh technique, are adopted. Additionally, a verification of the underwater launch simulation method and cavitation model is presented. Cavitating flow structure, wall vortex structures, and load characteristics are studied with a focus on the evolution mechanism of the cavitation flow field during the water-exit process. The results show that the attached cavitation rapidly collapses from top to bottom under the combined effect of large–medium density difference and reentry jet. Due to the presence of attachment cavitation, the development of the wall vortex structure represented by the hairpin vortex is inhibited. Considering the compressibility of the vapor phase, the peak of the synchronous collapse pressure is much larger than the collapse pressure with incompressibility. The pressure appears to be characterized by short widths and high peaks during the collapse of the water-exit. As the vehicle exits the water with a certain angle of attack, the range and peak of the cavitation collapse pressure rapidly reduce. In particular, the pressure side cavitation shedding and collapse behavior at the initial moment may lead to a larger pressure peak.
Microwave acoustic studies of materials in diamond anvil cell under high pressure
Authors: Sorokin Boris P. , Asafiev Nikita O. , Ovsyannikov Danila A. , Kvashnin Gennady M. , Popov Mikhail Yu. , Luparev Nikolay V. , Golovanov Anton V. , Blank Vladimir D.
Published: November 2022

This paper presents an integrated measuring system combining a diamond anvil cell (DAC) and a high overtone bulk acoustic resonator (HBAR) operating at the microwave frequency band as 2.8–8.8 GHz. We have studied several metallic (W, Zr) and semiconductor (Si) samples under pressure up to ∼16 GPa. As an HBAR, we have used the “Al/Al0.72Sc0.28N/Mo/(100) diamond” structure utilizing a piezoelectric aluminum–scandium nitride film. We have observed that under pressure, the Q-factor of the HBAR decreases but remains at the value of 2500–3000, which is suitable for our experiments. It is demonstrated that the above system can be used for studying the behavior of various solids under high pressure, the pressure-induced phase transition in Zr, the registration of plastic deformations, and their relaxation in metals. Here, we discussed the phenomenon of an acoustic wave passing through a tungsten layer under a pressure of ∼5.5 GPa. The integrated DAC&HBAR measuring system has demonstrated some practical advantages over known ultrasonic systems combined with the DAC as the possibility of applying a microwave operational frequency, the measurement of a Q-factor change under pressure, and the miniature size of a sensitive HBAR element. The application of the built-in DAC&HBAR system will hopefully allow more accurate studies on materials in the GPa pressure range of a DAC.
The dehydration performance and sorption behavior of PVA/silica hybrid pervaporative membrane
Authors: Yuan Haikuan , Bao Cun , Hao Ruiran , Lu Jie
Published: November 2022

A polyvinyl alcohol (PVA)/SiO2 organic-inorganic hybrid membrane was fabricated, using PVA as the basic material, SiO2 nanoparticles as the inorganic material, γ-(2,3)-glycidoxy propyl trimethoxysilane (GPTMS) and 3-aminopropyl triethoxysilane (APTEOS) as the second modified agents. The dehydration performance of PVA-SiO2/polyacrylonitrile (PAN) composite membrane to ethyl acetate (EA)/H2O, EA/ethanol (EtOH)/H2O and EA/EtOH/acetic acid (HAc)/H2O solutions was investigated. After modification of the second coupling agent of APTEOS or GPTMS, PVA-SiO2/PAN composite membrane had the better dehydration performance to these aqueous solutions. When dehydrating PVA-SiO2/PAN composite membrane modified by GPTMS (M5 membrane) in EA/H2O binary solution (98/2, wt%) at 40°C, the separation factor and the total permeation flux were 5245 and 293.9 g m−2 h−1, respectively. The preparation method of PVA/SiO2 membrane through adding the second coupling agent was simple, it had good dehydration performance and has excellent application prospects. The sorption behavior of PVA/SiO2 hybrid membrane was systematically studied, providing sufficient data for studying the separation mechanism of pervaporative membrane. The degree of swelling (DS) and the sorption selectivity of the membrane in different feed compositions and temperatures were measured to determine the static sorption of membrane. Dynamic sorption more clearly reflects the sorption and swelling processes of the membrane, and the dynamic sorption curves of the membrane in EA aqueous solutions were obtained. The sorption behavior of membrane to permeate components was studied by ATR-FTIR. Changes in the characteristic peaks for the permeate components and membrane indicated the sorption behavior of the membrane.
Analysis of copper(
Authors: Tobin Sean , Cassidy John , Kurian Kevin , Betts Anthony
Published: November 2022

In deionised water, ascorbic acid (AH−), through oxidation by oxygen in the presence of copper(ii), was found to degrade with zero-order kinetics. The magnitude of the reaction rate varied directly with the copper(ii) concentration. At a higher pH (7.4), the same reaction was found to be pseudo-first order. Once again, the magnitude of the rate increased linearly with copper(ii) concentration at a micromolar level. Dissolved oxygen levels, in excess AH− and trace copper(ii), displayed similar kinetics under both conditions. Monitoring of either AH− levels or dissolved oxygen concentration was found to be a useful novel undergraduate practical laboratory for trace copper(ii) determination. Students can measure the kinetics for standards and their unknown copper solution and quantitate the unknown copper.
Burnt wood management enhances soil multifunctionality at the medium term after a large wildfire in north-west Spain
Authors: Fernández-Guisuraga José Manuel , Calvo Leonor , Huerta Sara , Marcos Elena
Published: November 2022

Background Mulching and burnt wood treatments are commonly applied to prevent the loss of soil quality and erosion, but their effect on soil multifunctionality remains unexplored. Aims We filled this gap by assessing the medium-term (4 years) effects of these treatments on soil multifunctionality after a large wildfire in NW Spain. Methods Straw mulching (SM) and cut plus lopping (CpL) treatments were applied in high-severity affected areas of heathland plant communities. CpL areas had been afforested with Scots pine 15 years before the fire. We considered four soil functions estimated in treated and burned control plots 4 years after fire: (1) carbon regulation; (2) water regulation; (3) soil fertility; and (4) nutrient cycling. The functions were integrated into a multifunctionality index and linear models were used to evaluate treatments effect. Key results SM had no impact on individual functions and multifunctionality. Conversely, CpL with burnt Scots pine wood was able to sustain higher levels of multiple functions simultaneously than control areas. Consistent trade-offs between soil functions emerged in control areas for both treatments. Conclusions Burnt wood could ensure long-lasting effects to promote soil multifunctionality in Mediterranean ecosystems. Implications We recommend using a multifunctionality approach to avoid biases in treatment success.
Novel neutron decay mode inside neutron stars
Authors: Husain Wasif , Thomas Anthony W
Published: November 2022

We explore the suggestion that the neutron lifetime puzzle might be resolved by neutrons decaying into dark matter through the process, n → χ
χ
χ, with χ having a mass one-third of the neutron. In particular, we examine the consequences of such a decay mode for the properties of neutron stars. Unlike an earlier suggested decay mode, in order to satisfy the constraints on neutron star mass and tidal deformability, there is no need for a strong repulsive force between the dark matter particles. This study suggests the possibility of having hot dark matter at the core of the neutron star and presents a possible mechanism of dark matter cooling, and examines the possible signal of neutrons decaying in this way inside the neutron star right after its birth.
Kinetic modeling of interfacial abruptness in axial nanowire heterostructures
Authors: Leshchenko E D , Dubrovskii V G
Published: November 2022

Kinetic modeling of the formation of axial III–V nanowire heterostructures grown by the Au-catalyzed vapor–liquid–solid method is presented. The method is based on a combination of kinetic growth theory for different binaries at the liquid–solid interface and thermodynamics of ternary liquid and solid alloys. Non-stationary treatment of the compositional change obtained by swapping material fluxes allows us to compute the interfacial abruptness across nanowire heterostructures and leads to the following results. At high enough supersaturation in liquid, there is no segregation of dissimilar binaries in solid even for materials with strong interactions between III and V pairs, such as InGaAs. This leads to the suppression of the miscibility gaps by kinetic factors. Increasing the Au concentration widens the heterointerface at low Au content and narrows it at high Au content in a catalyst droplet. The model fits quite well the data on the compositional profiles across nanowire heterostructures based on both group III and group V interchange. Very sharp heterointerfaces in double of InAs/InP/InAs nanowire heterostructures is explained by a reduced reservoir effect due to low solubility of group V elements in liquid.
Flexibly manipulating the polarization independent plasmon-induced transparency in a graphene and strontium titanate integrated terahertz metasurface
Authors: Zhao Jianxing , Zhou Jianhong
Published: November 2022

We propose a graphene and strontium titanate (STO) integrated terahertz metasurface that can achieve the flexible manipulation of plasmon-induced transparency (PIT) effect. The proposed structure consists of a doped Si substrate, a SiO2 spacer, and a STO film with graphene antennas and Indium-Tin-Oxide (ITO) nanowhiskers electrodes patterned on it. By separately biasing the graphene antennas, the bright-bright mode coupled PIT effect is achieved. By flexibly configuring the Fermi energy distributions on the graphene antennas, the shape of PIT spectrum is also flexibly manipulated. Moreover, the working frequency band can be shifted by changing the environmental temperature due to the temperature dependent permittivity of the STO film. Our findings are beneficial in designing flexibly manipulated THz devices.
Jost states for the Deng-Fan potential
Authors: Saha D , Khirali B , Swain B , Bhoi J
Published: November 2022

Deng-Fan Potential is well known in describing diatomic molecular energy spectra and electromagnetic transitions. An irregular solution for the Deng-Fan potential is constructed by adapting the differential equation approach to the problem. The Jost function thus obtained is applied to find bound state energies and the scattering phase shifts for nuclear systems. Also phase function method has been applied in parallel with that of Jost function technique for similar investigation. Results show close agreement with the experimental ones. Exploiting the phase parameters the elastic scattering cross sections have been estimated.
Beam splitter as quantum coherence-maker
Authors: Ares Laura , Luis Alfredo
Published: November 2022

The aim of this work is to answer the question of how much quantum coherence a beam splitter is able to produce. To this end, we consider as the variables under study both the amount of coherence of the input states as well as the beam splitter characteristics. We conclude that there is an optimal combination of these factors making the gain of coherence maximum. In addition, the two-mode squeezed vacuum arises as the studied state most capable of gaining coherence when passing through a beam splitter. These results are qualitatively equivalent for the l1-norm of coherence and the relative entropy of coherence.
Affinity-based geometric discord and quantum speed limits of its creation and decay
Authors: Muthuganesan R , Balakrishnan S
Published: November 2022

In this article, we define a faithful quantifier of bipartite quantum correlation, namely geometric version of quantum discord using affinity based metric. It is shown that the newly-minted measure resolves the local ancilla problem of Hilbert-Schmidt measures. Exploiting the notion of affinity-based discord, we derive Margolus-Levitin (ML) and Mandelstamm-Tamm (MT) bounds for the quantum speed limit time for the creation and decay of quantum correlation. The dynamical study suggests that the affinity measure is a better resource compared to entanglement. Finally, we study the role of quantum correlation on quantum speed limit.
Disforming to conformal symmetry
Authors: Jiroušek Pavel , Shimada Keigo , Vikman Alexander , Yamaguchi Masahide
Published: November 2022

We analyse the dynamical properties of disformally transformed theories of gravity. We show that disformal transformation typically introduces novel degrees of freedom, equivalent to the mimetic dark matter, which possesses a Weyl-invariant formulation. We demonstrate that this phenomenon occurs in a wider variety of disformal transformations than previously thought.
Anisotropic 3D confinement of MCF-7 cells induces directed cell-migration and viscoelastic anisotropy of cell-membrane
Authors: Edwin Privita Edwina Rayappan George , Kumar Sumeet , Roy Srestha , Roy Basudev , Bajpai Saumendra Kumar
Published: November 2022

Tumor-associated collagen signature-3 (TACS-3) is a prognostic indicator for breast cancer survival. It is characterized by highly organized, parallel bundles of collagen fibers oriented perpendicular to the tumor boundary, serving as directional, confining channels for cancer cell invasion. Here we design a TACS-3-mimetic anisotropic, confined collagen I matrix and examine the relation between anisotropy of matrix, directed cellular migration, and anisotropy of cell membrane-the first direct contact between TACS-3 and cell-using Michigan Cancer Foundation-7 (MCF-7) cells as cancer-model. Using unidirectional freezing, we generated ∼50 μm-wide channels filled with collagen I. Optical tweezer (OT) microrheology shows that anisotropic confinement increases collagen viscoelasticity by two orders of magnitude, and the elastic modulus is significantly greater along the direction of anisotropic confinement compared to that along the orthogonal direction, thus establishing matrix anisotropy. Furthermore, MCF-7 cells embedded in anisotropic collagen I, exhibit directionality in cellular morphology and migration. Finally, using customized OT to trap polystyrene probes bound to cell-membrane (and not to ECM) of either free cells or cells under anisotropic confinement, we quantified the effect of matrix anisotropy on membrane viscoelasticity, both in-plane and out-of-plane, vis-à-vis the membrane. Both bulk and viscous modulus of cell-membrane of MCF-7 cells exhibit significant anisotropy under anisotropic confinement. Moreover, the cell membrane of MCF-7 cells under anisotropic confinement is significantly softer (both in-plane and out-of-plane moduli) despite their local environment being five times stiffer than free cells. In order to test if the coupling between anisotropy of extracellular matrix and anisotropy of cell-membrane is regulated by cell-cytoskeleton, actin cytoskeleton was depolymerized for both free and confined cells. Results show that cell membrane viscoelasticity of confined MCF-7 cells is unaffected by actin de-polymerization, in contrast to free cells. Together, these findings suggest that anisotropy of ECM induces directed migration and correlates with anisotropy of cell-membrane viscoelasticity of the MCF-7 cells in an actin-independent manner.
A novel and cost-effective optical detection of high magnitude current and magnetic pulses through a metallic cantilever
Authors: Ullah Rahim , Hussain Ghazanfar , Faisal Muhammad
Published: November 2022

We report a novel optical technique to measure short duration high magnitude current and magnetic pulses based on deflection of a macroscopic ferromagnetic cantilever. Deflection of the cantilever as a transducer takes place due to the attraction by an electromagnet. The reflected laser beam from a small thin mirror at tip of the cantilever is scanned over two spatially distinct photodetectors. Different high magnitude magnetic pulses are produced by discharging a capacitor bank through an inductive coil with a ferrite core. The response of the sensor is observed at different charging limits of the capacitor bank and spatial intervals between cantilever and inductive coil. A repeatable and linear response is detected by the devised sensors in the range 158.53–380.47 A current and 0.19–0.48 T magnetic field with sensitivity of 39.15 A kV−1 and 50.98 mT kV−1 for current and magnetic field amplitudes respectively in response to 2.5–6.0 kV charging of the capacitor bank. The proposed technique is remote, nondestructive, cost-effective and has a large dynamic range.
Time-dependent Aharonov–Casher effect on noncommutative space
Authors: Wang Tao , Ma Kai
Published: November 2022

In this paper, we study the time-dependent Aharonov–Casher effect and its corrections due to spatial noncommutativity. Given that the charge of the infinite line in the Aharonov–Casher effect can adiabatically vary with time, we show that the original Aharonov–Casher phase receives an adiabatic correction, which is characterized by the time-dependent charge density. Based on Seiberg–Witten map, we show that noncommutative corrections to the time-dependent Aharonov–Casher phase contains not only an adiabatic term but also a constant contribution depending on the frequency of the varying electric field.
Optical bistability and multistability via electron injection rate in an imperfect cavity
Authors: Askar Shavan , Jabbar Abdullah Hasan , A S Prakaash , Ibragimov Jakhongir , Bashar Bashar S , Kadhim Zainab Jawad , Akhmetov Linar , Alfilh Raed H C , Ramniwas Seema , Ramírez-Coronel Andrés Alexis
Published: November 2022

In this letter, we investigate the electron injection rate-based optical bistability (OB) and optical multistability (OM) features in an imperfect cavity. Coherent optical fields interact with the open four-level quantum system that makes up the ring cavity. We have discovered that the threshold of OB and OM as well as the length of the hysteresis loop can be changed by varying the length of the quantum system, reflection and transmission coefficient of cavity mirrors. Our findings further show that the electronic exit rate from the cavity and the electron injection rates have a significant impact on the threshold of OB and OM. It is discovered that transitioning from OB to OM or vice versa is achievable by adjusting the controllable parameters. The impact of the cooperation parameter on the properties of the OB and OM is then addressed. The findings demonstrate that the OB features are simple to manipulate. Our suggested model might be used to develop an all-optical device for use in upcoming quantum information processing.
Speech decoding from a small set of spatially segregated minimally invasive intracranial EEG electrodes with a compact and interpretable neural network
Authors: Petrosyan Artur , Voskoboinikov Alexey , Sukhinin Dmitrii , Makarova Anna , Skalnaya Anastasia , Arkhipova Nastasia , Sinkin Mikhail , Ossadtchi Alexei
Published: November 2022

Objective. Speech decoding, one of the most intriguing brain-computer interface applications, opens up plentiful opportunities from rehabilitation of patients to direct and seamless communication between human species. Typical solutions rely on invasive recordings with a large number of distributed electrodes implanted through craniotomy. Here we explored the possibility of creating speech prosthesis in a minimally invasive setting with a small number of spatially segregated intracranial electrodes. Approach. We collected one hour of data (from two sessions) in two patients implanted with invasive electrodes. We then used only the contacts that pertained to a single stereotactic electroencephalographic (sEEG) shaft or an electrocorticographic (ECoG) stripe to decode neural activity into 26 words and one silence class. We employed a compact convolutional network-based architecture whose spatial and temporal filter weights allow for a physiologically plausible interpretation. Main
results. We achieved on average 55% accuracy using only six channels of data recorded with a single minimally invasive sEEG electrode in the first patient and 70% accuracy using only eight channels of data recorded for a single ECoG strip in the second patient in classifying 26+1 overtly pronounced words. Our compact architecture did not require the use of pre-engineered features, learned fast and resulted in a stable, interpretable and physiologically meaningful decision rule successfully operating over a contiguous dataset collected during a different time interval than that used for training. Spatial characteristics of the pivotal neuronal populations corroborate with active and passive speech mapping results and exhibit the inverse space-frequency relationship characteristic of neural activity. Compared to other architectures our compact solution performed on par or better than those recently featured in neural speech decoding literature. Significance. We showcase the possibility of building a speech prosthesis with a small number of electrodes and based on a compact feature engineering free decoder derived from a small amount of training data.
Analogy of scaling law for heterogeneous interfacial fracture to explain the Gutenberg–Richter formula for earthquakes
Authors: Du Wei , Zhao Xiaohua , Hou Huiming , Fu Jinping , Su Jianxin
Published: November 2022

We propose a new approach for the statistical law due to the fracture of a heterogeneous interface involving spatial correlation of disorders. The dynamic process of interfacial fracture is governed by three coupled integral equations, which further become a system of linear algebraic equations after discretizing the interface to a set of prismatic elements. By tuning parameters, this model covers the whole cases of interfacial fracture from local-load-sharing to almost equal-load-sharing, extending the classical fiber bundle models to a general form. Numerical simulations present that in all cases, the statistical frequency distribution of bursts follows a power law with the exponent in the range (1.5, 2.5), the corresponding b-value in (0.75, 2.25), which well explains the empirical Gutenberg–Richter scaling. The exponent depends on stiffness of elastic spaces, heterogeneous properties of interface, and the distribution of displacements induced by loading. Furthermore, the exponent drops temporally with the evolution of fracture, to its final value before rupture of interface, a phenomenon that may be treated as a precursor for imminent catastrophic failure.
Single-ion anisotropy as the source of anomalies in thermodynamic properties of magnetic spin-1/2 − 1 mixed systems on square and simple cubic lattices
Authors: Jurčišinová E , Jurčišin M
Published: November 2022

The influence of the single-ion anisotropy on the thermodynamic properties of ferromagnetic as well as ferrimagnetic spin-1/2 − 1 mixed systems on the square and simple cubic lattice is investigated in the framework of the exactly solvable Ising-like models on the corresponding recursive lattices. The exact solutions of the models are present in the form of the explicit expressions for the free energy per site as the functions of the coordinates of the fixed points of the corresponding systems of recursion relations. The phase diagrams of the models are determined and the existence of compensation temperatures in the ferrimagnetic cases are discussed. The equations that drive the positions of the critical points are derived. The existence of the tricritical behavior in the three-dimensional system on the simple cubic lattice and its nonexistence in the case of the two-dimensional system on the square lattice is demonstrated. It is shown that the presence of the single-ion anisotropy can naturally lead to the emergence of the thermodynamic anomalies typical for frustrated magnetic systems even in unfrustrated ferromagnetic systems on studied bipartite lattices. First of all, the studied models exhibit the formation of strict residual-entropy hierarchies between the neighboring ground states of the system of three different ground states. It is also shown that due to this behavior of the entropy the specific heat capacity of the models exhibit anomalous (Schottky) behavior at low temperatures in the vicinity of the values of the anisotropy parameter, for which highly macroscopically degenerated single-point-like ground states are formed.
X-ray detectors at Diamond Light Source, evolution and future challenges
Authors: Tartoni N.
Published: November 2022

This note shows the evolution of detectors for crystallography at Diamond Light Source since it came into operation and how this evolution shaped the way the experiments are done. It is also highlighted the next detector challenges due to the increase in photon flux related to the planned upgrade of the machine.
Single photon counting performance of the Auratek-Square MCP-PMT
Authors: Calvi M. , Capelli S. , Carniti P. , Gotti C. , Pessina G.
Published: November 2022

This paper reports on the time resolution of the Auratek-Square MCP-PMT, a multi-anode microchannel plate photomultiplier produced by Photek.
When operating as single photon counter at low photon rate and with a single pixel illuminated it shows a transit time spread (jitter) of ∼100 ps FWHM, saturating at high rate, above ∼100 kHz/mm2.
The worsening of the timing performance depends on the bias voltage between the photocathode and the MCP input and between the MCP slabs.
The charge sharing between neighbouring pixels can become a major crosstalk source if not accounted for, degrading the time resolution to ∼170 ps FWHM when the entire pixel area is illuminated.
Study on SiPM performance at low temperatures between -60°C and -20°C
Authors: Zhong C. , Luo F.J. , Zheng B. , Wang X.D. , Bu M.Y. , Zou J. , Deng M.N.
Published: November 2022

Radon is the main background source of dark matter and neutrino experiments.
Radon concentration (mBq/m3) measurement by liquid scintillation detector is a highly sensitive method at low temperatures using silicon photomultipliers (SiPMs) arrays.
The SiPM performance characteristics are closely related to the lower detection limit of the detector. In this study, we built an automatic and accurate low-temperature measurement system to study the single photoelectron (SPE) spectrum, SPE resolution, optical crosstalk, and after-pulse of the SiPM at different temperatures. As a result, we obtained the variation trend of the SiPM parameters at different temperatures, and the SiPM optimal working conditions were obtained, which can improve the detector's sensitivity.