bluuebunny/crossref_metadata_2025 huggingface dataset:
Engineering graphene-based electrodes for optical neural stimulation
Authors: Rodrigues Artur Filipe , Tavares Ana P. M. , Simões Susana , Silva Rui P. F. F. , Sobrino Tomás , Figueiredo Bruno R. , Sales Goreti , Ferreira Lino
Published: December 2022

This work describes a covalently immobilized graphene-based nanocomposite for neural stimulation using NIR radiation. This platform is capable of delivering capacitive currents using biocompatible materials that are stable in the physiological milieu.
Ultra-small α-CsPbI3 perovskite quantum dots with stable, bright and pure red emission for Rec. 2020 display backlights
Authors: Wang Chuying , Meng Wen , Li Yacong , Xu Guangyong , Peng Min , Nie Shuming , Deng Zhengtao
Published: December 2022

The 4.2 nm α-CsPbI3 quantum dots - polymer composite films with 630 nm emission and high stability have been achieved, which are used for LED displays with color gamut to 96% of the Rec. 2020 standard.
Synthesis of dithioacetals via gold-catalysed hydrothiolation of vinyl sulfides
Authors: Murugesh Venkatesh , Ryou Bokyeong , Park Cheol-Min
Published: December 2022

An efficient method for the synthesis of both symmetrically and unsymmetrically substituted dithioacetals from vinyl sulfides.
Synthesis of isoindigo-derived conjugated polymers via ball-milling metal-free polymerization
Authors: Zheng Yingxuan , Li Zefeng , Deng Ping , Yu Yan
Published: December 2022

Isoindigo-derived conjugated polymers have been synthesized via ball-milling metal-free polymerization in the presence of readily available tris(diethylamino)phosphine under ambient conditions.
Correction: Fluorine-containing nano-objects with the same compositions but different segment distributions: synthesis, characterization and comparison
Authors: Chai Xingpeng , Zhou Peng , Xia Qi , Shi Boyang , Wang Guowei
Published: December 2022

Correction for ‘Fluorine-containing nano-objects with the same compositions but different segment distributions: synthesis, characterization and comparison’ by Xingpeng Chai et al., Polym. Chem., 2022, 13, 6293–6301, https://doi.org/10.1039/d2py01148d.
Highly oxidized U(vi) within the smallest fullerene: gas-phase synthesis and computational study of boron-doped U@C27B
Authors: Moreno-Vicente Antonio , Alías-Rodríguez Marc , Dunk Paul W. , de Graaf Coen , Poblet Josep M. , Rodríguez-Fortea Antonio
Published: December 2022

The smallest borafullerene U@C27B has been synthesized using a laser vaporization cluster source. The U atom, placed in the middle of the cage and interacting with all the 28 atoms, is formally described as highly oxidized U(vi).
Discovering the role of N-heterocyclic carbene as hydrogen borrowing organocatalyst: metal-free, directN-alkylation of amines with benzyl alcohols
Authors: Sharma Richa , Rahaman T A Abdul , Sen Janmejaya , Mashevskaya Irina V. , Chaudhary Sandeep
Published: December 2022

A highly sustainable, bench-stable, inexpensive, non-toxic and commercially available N-heterocyclic carbene based hydrogen borrowing organocatalyst for the direct N-alkylation of amines with alcohols is reported.
4,5-Disubstituted pyrenes from phenangermoles
Authors: Qian Cheng-Gang , Xiao Bin
Published: December 2022

The synthesis of discriminated 4,5-disubstitued pyrene from phenangermoles is accomplished via a Pd-catalyzed annulative π-extension reaction.
Enhanced photocatalytic activity of a flower-like In2O3/ZnGa2O4:Cr heterojunction composite with long persisting luminescence
Authors: Tuerdi Ailijiang , Yan Peng , He Fenggui , Abdukayum Abdukader
Published: December 2022

Flower-like In2O3/ZnGa2O4:Cr heterojunction composites not only have high photocatalytic efficiency for rhodamine B degradation, but also have a long persisting luminescence performance.
Review of photoresponsive and glycoside dendrimers in biomaterials and sensors applications
Authors: Rajasekar Mani , Sree Agash Saravanan Geetha , Rajasekar Kumarasan
Published: December 2022

Dendrimers are branched molecules with well-defined lengths, shapes, molecular weights, and monodispersity in comparison to linear polymers.
Structurally diverse biflavonoids from Dysosma versipellis and their bioactivity
Authors: Sun Yan-Jun , Han Rui-Jie , Bai Hong-Yun , Wang Hao-jie , Li Meng , Si Ying-Ying , Wang Jun-Min , Gong Jian-Hong , Chen Hui , Feng Wei-Sheng
Published: December 2022

Five pairs of new biflavonoid enantiomers, (±)-dysosmabiflavonoids A–E (1–5), two new biflavonoids, dysosmabiflavonoids F–G (6–7), and four biosynthetically related precursors (8–11) were isolated from the roots and rhizomes of Dysosma versipellis.
Cu-catalyzed enantioselective decarboxylative cyanation via the synergistic merger of photocatalysis and electrochemistry
Authors: Yuan Yin , Yang Junfeng , Zhang Junliang
Published: December 2022

Proof of concept enantioselective transformation via photoelectrocatalysis was reported on Cu-catalyzed enantioselective decarboxylative cyanation, which features mild conditions, high enantioselectivity and a reasonable range of functionalities.
Injectable catechin-based supramolecular hydrogel for highly efficient application in HPV-associated OSCC
Authors: Lei Shangxue , Hu Xiaopei , Song Shaojuan , Zhang Yuting , Zhao Hang , Xu Xiaoping , Dan Hongxia
Published: December 2022

The created injectable CPBisoG supramolecular hydrogel not only acted as a good local drug delivery platform with good stability, self-healing properties, biodegradability, and biocompatibility, but also exhibited inhibition effects toward HPV+ OSCC.
Functionalized diketopyrrolopyrrole compounds for NIR-to-visible photon upconversion
Authors: Naimovičius Lukas , Radiunas Edvinas , Chatinovska Barbara , Jozeliūnaitė Augustina , Orentas Edvinas , Kazlauskas Karolis
Published: December 2022

Diketopyrrolopyrrole derivatives demonstrating moderate NIR-to-Vis TTA-mediated photon upconversion quantum yield (up to 3.8% out of 50%) and statistical probabilityf(up to 15.6%) are promoted as stable alternatives to a rubrene emitter.
Particle dispersion system consisting of helically assembled liquid crystalline poly(para-phenylene)derivatives with reproducible chiroptical properties
Authors: Horie Keita , Kondo Shunsuke , Akagi Kazuo
Published: December 2022

A liquid crystalline poly(para-phenylene) derivative forms a helically π-stacked structure upon addition of a chiral binaphthyl compound, exhibiting blue circularly polarized luminescence.
Low-toxicity chemical solution deposition of ferroelectric Ca:HfO2
Authors: Badillo Miguel , Taleb Sepide , Mokabber Taraneh , Rieck Jan , Castanedo Rebeca , Torres Gerardo , Noheda Beatriz , Acuautla Mónica
Published: December 2022

Simple, stable, and low-toxicity chemical solution for deposition of ferroelectric Ca:HfO2 films.
Unique excitation power density and pulse width-dependent multicolor upconversion emissions of Y2Mo4O15:Yb3+,Ho3+ for anti-counterfeiting and information encryption applications
Authors: Li Yiying , You Wenwu , Zhao Jun , Zhang Xiaomin , Pan Gencai , Liu Pingan , Mao Yanli
Published: December 2022

A unique smart upconversion material Y2Mo4O15:40%Yb3+,2%Ho3+ that can respond to the power density and pulse width of the excitation light is developed.
Speaking Rate, Immediate Memory, and Grammatical Processing in Prelingual Cochlear Implant Recipients
Authors: Shin Sujin , Warner-Czyz Andrea , Geers Ann , Katz William F.
Published: December 2022

Purpose:

This study examined the extent to which prelingual cochlear implant (CI) users show a slowed speaking rate compared with typical-hearing (TH) talkers when repeating various speech stimuli and whether the slowed speech of CI users relates to their immediate verbal memory.

Method:

Participants included 10 prelingually deaf teenagers who received CIs before the age of 5 years and 10 age-matched TH teenagers. Participants repeated nonword syllable strings, word strings, and center-embedded sentences, with conditions balanced for syllable length and metrical structure. Participants' digit span forward and backward scores were collected to measure immediate verbal memory. Speaking rate data were analyzed using a mixed-design, repeated-measures analysis of variance, and the relationships between speaking rate and digit spans were evaluated by Pearson correlation.

Results:

Participants with CIs spoke more slowly than their TH peers during the sentence repetition task but not in the nonword string and word string repetition tasks. For the CI group, significant correlations emerged between speaking rate and digit span scores (both forward and backward) for the sentence repetition task but not for the nonword string or word string repetition task. For the TH group, no significant correlations were found.

Conclusions:

The findings indicate a relation between slowed speech production, reduced immediate verbal memory, and diminished language capabilities of prelingual CI users, particularly for syntactic processing. These results support theories claiming that immediate memory, including components of a central executive, influences the speaking rate of these talkers. Implications for therapies designed to increase speech fluency in CI recipients are discussed.

Supplemental Material:

https://doi.org/10.23641/asha.21644795
The LOFAR Tied-Array All-Sky Survey: Timing of 35 radio pulsars and an overview of the properties of the LOFAR pulsar discoveries
Authors: van der Wateren E. , Bassa C. G. , Cooper S. , Grießmeier J.-M. , Stappers B. W. , Hessels J. W. T. , Kondratiev V. I. , Michilli D. , Tan C. M. , Tiburzi C. , Weltevrede P. , Bak Nielsen A.-S. , Carozzi T. D. , Ciardi B. , Cognard I. , Dettmar R.-J. , Karastergiou A. , Kramer M. , Künsemöller J. , Osłowski S. , Serylak M. , Vocks C. , Wucknitz O.
Published: December 2022

The LOFAR Tied-Array All-Sky Survey (LOTAAS) is the most sensitive untargeted radio pulsar survey performed at low radio frequencies (119−151 MHz) to date and has discovered 76 new radio pulsars, including the 23.5-s pulsar J0250+5854, which up until recently was the slowest spinning radio pulsar known. In this paper, we report on the timing solutions of 35 pulsars discovered by LOTAAS, which include a nulling pulsar and a mildly recycled pulsar, and thereby complete the full timing analysis of the LOTAAS pulsar discoveries. We give an overview of the findings from the full LOTAAS sample of 76 pulsars, discussing their pulse profiles, radio spectra, and timing parameters. We found that the pulse profiles of some of the pulsars show profile variations in time or frequency, and while some pulsars show signs of scattering, a large majority display no pulse broadening. The LOTAAS discoveries have on average steeper radio spectra and longer spin periods (1.4×), as well as lower spin-down rates (3.1×) compared to the known pulsar population. We discuss the cause of these differences and attribute them to a combination of selection effects of the LOTAAS survey as well as previous pulsar surveys, though we cannot rule out that older pulsars tend to have steeper radio spectra.
Superconvergence and postprocessing of the continuous Galerkin method for nonlinear Volterra integro-differential equations
Authors: Zhang Mingzhu , Mao Xinyu , Yi Lijun
Published: December 2022

We propose a novel postprocessing technique for improving the global accuracy of the continuous Galerkin (CG) method for nonlinear Volterra integro-differential equations. The key idea behind the postprocessing technique is to add a higher order Lobatto polynomial of degree k + 1 to the CG approximation of degree k. We first show that the CG method superconverges at the nodal points of the time partition. We further prove that the postprocessed CG approximation converges one order faster than the unprocessed CG approximation in the L2-, H1- and L∞-norms. As a by-product of the postprocessed superconvergence results, we construct several a posteriori error estimators and prove that they are asymptotically exact. Numerical examples are presented to highlight the superconvergence properties of the postprocessed CG approximations and the robustness of the a posteriori error estimators.
COVID-19 – (noch) Krise oder (schon)
Epikrise?
Authors: Wildner Manfred
Published: December 2022

Das Jahresende als Übergangszeit und die weihnachtliche Besinnungszeit laden
dazu ein, neben anderen Krisen auch über das 2022/2023 noch
anhaltende Krisenthema COVID-19 nachzudenken. Die Bezeichnung Krise ist
allgegenwärtig: Sie bezieht sich auf eine schwierige Situation, bisweilen
auf den Höhe- oder auch Wendepunkt einer gefährlichen Entwicklung,
der einer fortlaufenden Beurteilung bedarf. Der Begriff der Epikrise (griech.
epi: nach, krisis: Beurteilung) ist zumindest den ärztlichen
Leserinnen und Lesern ebenfalls vertraut: Er bezieht sich auf die Schlussbetrachtung
eines Krankheitsverlaufs, mithin eine differenzierende Darstellung und Beurteilung
nach Abschluss des konkreten Behandlungsfalls. Will man diese Schlussbetrachtung von
der Individualmedizin auf die Bevölkerungsmedizin übertragen,
stößt dieser Ansatz allerdings sehr schnell auch auf
Widerstände. Zum einen wegen der grundsätzlichen
Unterschiedlichkeiten eines Krankheitsverlaufs bei einzelnen Menschen
gegenüber dem epidemischen Verlauf aus Bevölkerungsperspektive, zum
anderen könnte man auf die vergleichsweise hoch entwickelten diagnostischen,
therapeutischen und prognostischen Werkzeuge der Individualmedizin gegenüber
den teilweise noch unterentwickelt scheinenden Instrumenten im Bereich von
Öffentlicher Gesundheit/ Public Health verweisen und zum dritten
stellt sich auch die Frage, ob bei COVID-19 als pandemischem Geschehen
überhaupt schon eine Epikrise möglich ist.
Outpatient Foley Catheter for Induction of Labor in Obese Nulliparous Patients: A Secondary Analysis of OFFSITE II Randomized Controlled Trial
Authors: Seasely Angela R. , Xue Yumo , Ausbeck Elizabeth B. , Jauk Victoria C. , Blanchard Christina T. , Files Pamela , Kuper Spencer C. , Casey Brian M. , Szychowski Jeff M. , Harper Lorie M. , Tita Alan T. , Subramaniam Akila
Published: December 2022

Objective In the OFFSITE II randomized controlled trial, outpatient cervical ripening with a Foley catheter (CF) in nulliparous patients undergoing elective induction of labor (eIOL) shortened the time from admission to delivery. Given that patients with obesity have protracted labor and higher rates of failed IOL, we sought to determine if outpatient ripening with a CF may be even more beneficial for this high-risk group.

Study Design We performed a secondary analysis of the OFFSITE II randomized controlled trial. For this analysis, all patients from the primary trial were classified by their intervention assignment (inpatient vs. outpatient) and also by their admission body mass index (BMI) class (BMI ≥ 30 and BMI < 30 kg/m2). The primary outcome was time from labor and delivery (L&D) admission to delivery. Secondary outcomes included cesarean delivery, time from admission to hospital discharge, and rates of clinically diagnosed chorioamnionitis and endometritis.

Results In patients with BMI ≥ 30, the primary outcome, time from admission to delivery, (18.0 [13.5–20.9] vs. 20.4 [16.6–31.3] hours, p = 0.01), as well as total hospitalization length (3.2 [2.5–3.3] vs. 3.4 [3.1–4.3] days, p = 0.02) were shorter in the outpatient group. There were no differences in rates of chorioamnionitis or endometritis in outpatient compared with inpatient CF. Furthermore, in those with a BMI ≥ 30, the cesarean rate was significantly lower with outpatient CF (19.4% vs. 44.7%, p = 0.03); it was not statistically different in patients with BMI < 30.

Conclusion In this exploratory retrospective secondary analysis of the OFFSITE II randomized control trial, we found that in patients with BMI ≥ 30 undergoing eIOL, outpatient CF was associated with a lower time from L&D admission until delivery. This was also associated with a shorter time of total hospital duration and decreased the rate of cesarean, a benefit not detected in the overall analysis presented in the primary study. In nulliparas undergoing induction of labor, ripening with outpatient cervical Foley may even more significantly reduce labor duration, total hospital duration, and the rate of cesarean in patients with obesity.

Key Points
Hydrogen states described by solutions of the Dirac equation: Role of spinor invariants
Authors: Eremko A. A. , Brizhik L. S.
Published: December 2022

The solution of the Dirac equation with the Coulomb potential is used to analyze bound electron states in a hydrogen atom. The analysis is based on the fact that such states are characterized by a set of quantum numbers which describe definite values of the complete set of physical quantities that can be determined simultaneously. This set includes the energy, square of the total angular momentum, one of its component and a spinor invariant. The latter, spinor invariant gives two-valued quantum number which determines the sign of its eigenvalue. In addition to the known Dirac and Johnson–Lippman invariant, there exists a new one. Operators of these three spinor invariants do not commute between themselves which results in the degeneracy of the energy levels with respect to the two-valued quantum number. Three different systems of the eigenbispinor corresponding to the three spinor invariants are obtained and the generalized solution with free parameters is calculated. Variation of the free parameters transforms one particular solution into any other. It is shown that the electron probability densities and spin polarizations in an electron cloud depend essentially on the invariant set, demonstrating physical difference of the states corresponding to different spinor invariants.
Bound states of a one-dimensional Dirac equation with multiple delta-potentials
Authors: Gusynin V. P. , Sobol O. O. , Zolotaryuk A. V. , Zolotaryuk Y.
Published: December 2022

Two approaches are developed for the study of the bound states of a one-dimensional Dirac equation with the potential consisting of N δ-function centers. One of these uses Green’s function method. This method is applicable to a finite number N of δ-point centers, reducing the bound state problem to finding the energy eigenvalues from the determinant of a 2 N × 2 N matrix. The second approach starts with the matrix for a single delta-center that connects the two-sided boundary conditions for this center. This connection matrix is obtained from the squeezing limit of a piecewise constant approximation of the delta-function. Having then the connection matrices for each center, the transmission matrix for the whole system is obtained by multiplying the one-center connection matrices and the free transfer matrices between neighbor centers. An equation for bound state energies is derived in terms of the elements of the total transfer matrix. Within both approaches, the transcendental equations for bound state energies are derived, the solutions to which depend on the strength of delta-centers and the distance between them, and this dependence is illustrated by numerical calculations. The bound state energies for the potentials composed of one, two, and three delta-centers (N = 1, 2, 3) are computed explicitly. The principle of strength additivity is analyzed in the limits as the delta-centers merge at a single point or diverge to infinity.
Scattering by singular potentials in coupled Schrödinger equations
Authors: Christiansen Peter L. , Rasmussen Jens Juul , Sørensen Mads Peter
Published: December 2022

Scattering in pairs of one-dimensional time-independent Schrödinger equations coupled via singular potentials are considered. For potentials given by Dirac’s delta function reflected and transmitted waves of the two modes as well as a bound state is found by integration. For potentials given by the derivative of Dirac’s delta function, resonant reflection and transmission occur for a discrete set of amplitudes of the scattering potential. These results depend on the applied regularization.
A fresh look at spreading respiratory infections via speech
Authors: Thompson Avery
Published: December 2022

Experimental approach examines how vibrating vocal folds produce aerosol particles.
Quasi-factorization and multiplicative comparison of subalgebra-relative entropy
Authors: LaRacuente Nicholas
Published: December 2022

Purely multiplicative comparisons of quantum relative entropy are desirable but challenging to prove. We show such comparisons for relative entropies between comparable densities, including the relative entropy of a density with respect to its subalgebraic restriction. These inequalities are asymptotically tight in approaching known, tight inequalities as perturbation size approaches zero. Based on these results, we obtain a kind of inequality known as quasi-factorization or approximate tensorization of relative entropy. Quasi-factorization lower bounds the sum of a density’s relative entropies to several subalgebraic restrictions in terms of its relative entropy to their intersection’s subalgebraic restriction. As applications, quasi-factorization implies uncertainty-like relations, and with an iteration trick, it yields decay estimates of optimal asymptotic order on mixing processes described by finite, connected, undirected graphs.
Eigenvalues of a periodic Schrödinger operator perturbed by a fast decaying potential
Authors: Safronov Oleg
Published: December 2022

Let [λ, μ] be an interval contained in a spectral gap of a periodic Schrödinger operator H. Consider H(α) = H − αV, where V is a fast decaying positive function. We study the asymptotic behavior of the number of eigenvalues of H(α) in [λ, μ] as α → ∞.
Extracting the excitonic Hamiltonian of a chlorophyll dimer from broadband two-dimensional electronic spectroscopy
Authors: Zakutauskaitė Kristina , Mačernis Mindaugas , Nguyen Hoang H. , Ogilvie Jennifer P. , Abramavičius Darius
Published: December 2022

We apply Frenkel exciton theory to model the entire Q-band of a tightly bound chlorophyll dimer inspired by the photosynthetic reaction center of photosystem II. The potential of broadband two-dimensional electronic spectroscopy experiment spanning the Qx and Qy regions to extract the parameters of the model dimer Hamiltonian is examined through theoretical simulations of the experiment. We find that the local nature of Qx excitation enables identification of molecular properties of the delocalized Qy excitons. Specifically, we demonstrate that the cross-peak region, where excitation energy is resonant with Qy while detection is at Qx, contains specific spectral signatures that can reveal the full real-space molecular Hamiltonian, a task that is impossible by considering the Qy transitions alone. System–bath coupling and site energy disorder in realistic systems may limit the resolution of these spectral signatures due to spectral congestion.
Overcritical electron acceleration and betatron radiation in the bubble-like structure formed by re-injected electrons in a tailored transverse plasma
Authors: Zhao Yuan , Lu Haiyang , Zhou Cangtao , Zhu Jungao
Published: December 2022

We present a novel scheme for dense electron acceleration driven by the laser irradiation of a near-critical-density plasma. The electron reflux effect in a transversely tailored plasma is particularly enhanced in the area of peak density. We observe a bubble-like distribution of re-injected electrons, which forms a strong quasistatic electromagnetic field that can accelerate electrons longitudinally while also preserving the electron transverse emittance. Simulation results demonstrate that over-dense electrons could be trapped in such an artificial bubble and accelerated to an energy of ∼500MeV. The obtained relativistic electron beam can reach a total charge of up to 0.26 nC and is well collimated with a small divergence of 17 mrad. Moreover, the wavelength of electron oscillation is noticeably reduced due to the shaking of the bubble structure in the laser field. As a result, the energy of the produced photons is substantially increased to the γ range. This new regime provides a path to generating high-charge electron beams and high-energy γ-ray sources.
Microscopic analysis of Trichel's pulse characteristics and the effect of air pressure and temperature
Authors: Zhang Zhanlong , Deng Bowen , Deng Jun , Dai Youquan , Zhao Hui , Dong Zijian
Published: December 2022

The negative direct current corona discharge experiment under the needle-plate electrode is conducted, and the typical Trichel pulse waveform is obtained. Furthermore, to analyze the microscopic process of corona discharge, a plasma-fluid discharge simulation model, including air chemical reactions, is established, and a Trichel pulse waveform is obtained, which is consistent with the experimentally obtained waveform. Thus, the chemical reaction that plays a dominant role in the generation and disappearance of charged particles as well as the spatiotemporal distribution and quantitative variation of charged particles during the discharge process are clarified. On this basis, the variation of the microscopic and macroscopic parameters in the discharge process under different air pressure and temperature conditions is studied. The results show that microscopic parameters, such as charge density and electric field intensity, are negatively associated with air pressure and positively associated with temperature, while macroscopic parameters, such as Trichel pulse average current, average peak current, and discharge frequency, are positively associated with the microscopic parameters.
Stochastic artificial synapses based on nanoscale magnetic tunnel junction for neuromorphic applications
Authors: Lv Wenxing , Cai Jialin , Tu Huayao , Zhang Like , Li Rongxin , Yuan Zhe , Finocchio Giovanni , Li Shuping , Sun Xuemei , Bian Lifeng , Zhang Baoshun , Xiong Rui , Zeng Zhongming
Published: December 2022

Bio-inspired neuromorphic computing has aroused great interest due to its potential to realize on-chip learning with bio-plausibility and energy efficiency. Realizing spike-timing-dependent plasticity (STDP) in synaptic electronics is critical toward bio-inspired neuromorphic computing systems. Here, we report on stochastic artificial synapses based on nanoscale magnetic tunnel junctions that can implement STDP harnessing stochastic magnetization switching. We further demonstrate that both the magnitude and the temporal requirements for STDP can be modulated via engineering the pre- and post-synaptic voltage pulses. Moreover, based on arrays of binary magnetic synapses, unsupervised learning can be realized for neuromorphic computing tasks such as pattern recognition with great computing accuracy and efficiency. Our study suggests a potential route toward on-chip neuromorphic computing systems.
Initial experimental results on a superconducting-qubit reset based on photon-assisted quasiparticle tunneling
Authors: Sevriuk V. A. , Liu W. , Rönkkö J. , Hsu H. , Marxer F. , Mörstedt T. F. , Partanen M. , Räbinä J. , Venkatesh M. , Hotari J. , Grönberg L. , Heinsoo J. , Li T. , Tuorila J. , Chan K. W. , Hassel J. , Tan K. Y. , Möttönen M.
Published: December 2022

We present here our recent results on qubit reset scheme based on a quantum-circuit refrigerator (QCR). In particular, we use the photon-assisted quasiparticle tunneling through a superconductor–insulator–normal-metal–insulator–superconductor junction to controllably decrease the energy relaxation time of the qubit during the QCR operation. In our experiment, we use a transmon qubit with dispersive readout. The QCR is capacitively coupled to the qubit through its normal-metal island. We employ rapid, square-shaped QCR control voltage pulses with durations in the range of 2–350 ns and a variety of amplitudes to optimize the reset time and fidelity. Consequently, we reach a qubit ground-state probability of roughly 97% with 80-ns pulses starting from the first excited state. The qubit state probability is extracted from averaged readout signal, where the calibration is based on Rabi oscillations, thus not distinguishing the residual thermal population of the qubit.
On the irregular jet formation of shock-accelerated spherical heavy gas bubbles
Authors: Guan Ben , Yang Hongsen , Yang Haiwei , Wang Ge
Published: December 2022

The behaviors of shock-accelerated heavy gas bubbles are numerically investigated, focusing on clarifying the forming mechanisms of the bubble jets in different types. The present study categorizes heavy bubble jets into two types, regular jets, and irregular jets. The present shock-accelerated multi-component flows are simulated by solving inviscid compressible Euler equations. An upwind characteristic space-time conservation element solution element scheme is adopted, and a five-equation model is used to treat the gas interface. Bubbles of R22, SF6, and Kr in ambient N2 and air are examined, and the incident shock Mach numbers are 1.1 and 1.23. The numerical results demonstrate that the bubble jet formation and its shape are very sensitive to the test gas species and incident shock strength. It is found that the tiny upstream jet formed in the single-shocked SF6/air scenario results from a very small Mach stem impingement onto the bubble upstream interface, the type II shock-shock interaction features the flow mechanism. While the large upstream jet formed in the re-shock SF6/air scenario is a combined result of the re-shock convergence and later vortex stretching. For the complex Kr/air scenario, the upstream jet results from the vorticity-induced inward jet stretching, and the downstream hollow jet results from the slip line guided tip extension. The measurements of bubble volumes, gas mixings, and material line lengths suggest that, although the jet formation greatly changes the bubble morphology, it makes a minor contribution to the bubble overall integral properties.
Treelike thermal structures on the water surface: Surface film modeling
Authors: Zvonarev K. V. , Rusova D. A. , Martyushev L. M.
Published: December 2022

The hypothesis that the previously discovered treelike thermal structures on water surface [Martyushev et al. “Treelike thermal structures on the water surface,” Phys. Fluids 34, 053112 (2022)] can be explained by the presence of a surface-active impurity film is being investigated. It is shown that a simple mathematical model of the film based on a free-slip condition on the water surface allows us to obtain the previously observed structures. At the same time, a no-slip boundary condition leads to results that are inconsistent with the experiment. In addition to the film, the presence of convective structures due to horizontal and vertical temperature gradients in the water layer with an aspect ratio of about 5 is important for the appearance of treelike structures on the surface.
Diameter-dependent ultrafast lithium-ion transport in carbon nanotubes
Authors: Fu Zhong-Heng , Chen Xiang , Yao Nan , Yu Le-Geng , Shen Xin , Shi Shaochen , Zhang Rui , Sha Zhengju , Feng Shuai , Xia Yu , Zhang Qiang
Published: December 2022

Ion transport in solids is a key topic in solid-state ionics. It is critical but challenging to understand the relationship between material structures and ion transport. Nanochannels in crystals provide ion transport pathways, which are responsible for the fast ion transport in fast lithium (Li)-ion conductors. The controlled synthesis of carbon nanotubes (CNTs) provides a promising approach to artificially regulating nanochannels. Herein, the CNTs with a diameter of 5.5 Å are predicted to exhibit an ultralow Li-ion diffusion barrier of about 10 meV, much lower than those in routine solid electrolyte materials. Such a characteristic is attributed to the similar chemical environment of a Li ion during its diffusion based on atomic and electronic structure analyses. The concerted diffusion of Li ions ensures high ionic conductivities of CNTs. These results not only reveal the immense potential of CNTs for fast Li-ion transport but also provide a new understanding for rationally designing solid materials with high ionic conductivities.
Microtubule nucleation complex behavior is critical for cortical array homogeneity
and
xylem wall patterning
Authors: Jacobs Bas , Schneider René , Molenaar Jaap , Filion Laura , Deinum Eva E.
Published: December 2022

Plant cell walls are versatile materials that can adopt a wide range of mechanical properties through controlled deposition of cellulose fibrils. Wall integrity requires a sufficiently homogeneous fibril distribution to cope effectively with wall stresses. Additionally, specific conditions, such as the negative pressure in water transporting xylem vessels, may require more complex wall patterns, e.g., bands in protoxylem. The orientation and patterning of cellulose fibrils are guided by dynamic cortical microtubules. New microtubules are predominantly nucleated from parent microtubules causing positive feedback on local microtubule density with the potential to yield highly inhomogeneous patterns. Inhomogeneity indeed appears in all current cortical array simulations that include microtubule-based nucleation, suggesting that plant cells must possess an as-yet unknown balancing mechanism to prevent it. Here, in a combined simulation and experimental approach, we show that a limited local recruitment of nucleation complexes to microtubules can counter the positive feedback, whereas local tubulin depletion cannot. We observe that nucleation complexes preferentially appear at the plasma membrane near microtubules. By incorporating our experimental findings in stochastic simulations, we find that the spatial behavior of nucleation complexes delicately balances the positive feedback, such that differences in local microtubule dynamics—as in developing protoxylem—can quickly turn a homogeneous array into a banded one. Our results provide insight into how the plant cytoskeleton has evolved to meet diverse mechanical requirements and greatly increase the predictive power of computational cell biology studies.
Investigating the vibration response and modulation mechanism for health monitoring of wind turbine planetary gearboxes using a tribodynamics-based analytical model
Authors: Li Junjie , Tong Shuiguang , Tong Zheming , Li Hongkun , Cong Feiyun , Cheng Weihao , Dong Guangming
Published: December 2022

In a wind turbine (WT) planetary gearbox system, the characteristics of incipient faults are difficult to recognize with increasing friction under a lack of lubrication condition. To this end, a translational–torsional coupled nonlinear tribodynamic model considering local faults is developed. A fitted time-varying transfer function is obtained using an impact experiment excited by a planet gear with a missing tooth and is further used to represent the modulation effect caused by the carrier. Using the proposed analytical model, the vibration response and modulation mechanism of the resultant signal under the coupling effect of tooth root crack and sliding friction are investigated. It is demonstrated that specific sidebands are greatly excited and the spectrum structure becomes extremely complex after the introduction of friction. Based on these results, sideband indicators are obtained to monitor the lubrication state and detect incipient faults. The experimental results based on an in-house WT drivetrain testbench are in good agreement with the simulation results.
Foreground segmentation and location of coal and gangue under complex similar background
Authors: Luo Qisheng , Wang Shuang , Guo Yongcun , He Lei , Cheng Gang , Li Xin
Published: December 2022

To improve the foreground segmentation and location accuracy of complex coal gangue images with gray histogram distribution close to the unimodal shape, a contour detection algorithm of the grayscale fluctuation matrix is proposed. The contour and non-contour pixels of coal and gangue images are investigated, and the result indicates that the gray values of the pixels around the contour exhibit the non-uniform distribution, and the gray value changes in different directions are significantly different. Accordingly, a grayscale fluctuation matrix is built by calculating the change amplitude of pixels in different directions, and multiple features are extracted from the grayscale fluctuation matrix to realize the target contour segmentation. Furthermore, the contour is optimized using the historical and future information of the contour image, thus effectively removing numerous false contours, reproducing some hidden contours and increasing segmentation accuracy. This method has high accuracy, and the maximum error rates of the pixel area and center coordinate of contour detection are 4.404% and 3.18% respectively. This study provides a feasible solution to the edge detection and segmentation of images with similar and complex backgrounds.
Simulation study of a brain PET scanner using TOF-DOI detectors equipped with first interaction position detection
Authors: Li Yingying , Watanabe Mitsuo , Isobe Takashi , Ote Kibo , Tokui Aoi , Omura Tomohide , Liu Huafeng
Published: December 2022

Objective. The aim of this study is to evaluate the performance characteristics of a brain positron emission tomography (PET) scanner composed of four-layer independent read-out time-of-flight depth-of-interaction (TOF-DOI) detectors capable of first interaction position (FIP) detection, using Geant4 application for tomographic emission(GATE). This includes the spatial resolution, sensitivity, count rate capability, and reconstructed image quality. Approach. The proposed TOF-DOI PET detector comprises four layers of a 50 × 50 cerium-doped lutetium–yttrium oxyorthosilicate (LYSO:Ce) scintillator array with 1 mm pitch size, coupled to a 16 × 16 multi-pixel photon counter array with 3.0 mm × 3.0 mm photosensitive segments. Along the direction distant from the center field-of-view (FOV), the scintillator thickness of the four layers is 2.5, 3, 4, and 6 mm. The four layers were simulated with a 150 ps coincidence time resolution and the independent readout make the FIP detection capable. The spatial resolution and imaging performance were compared among the true-FIP, winner-takes-all (WTA) and front-layer FIP (FL-FIP) methods (FL-FIP selects the interaction position located on the front-most interaction layer in all the interaction layers). The National Electrical Manufacturers Association NU 2-2018 procedure was referred and modified to evaluate the performance of proposed scanner. Main results. In detector evaluation, the intrinsic spatial resolutions were 0.52 and 0.76 mm full width at half-maximum (FWHM) at 0° and 30° incident γ-rays in the first layer pair, respectively. The reconstructed spatial resolution by the filter backprojection (FBP) achieved sub-millimeter FWHM on average over the whole FOV. The maximum true count rate was 207.6 kcps at 15 kBq ml−1 and the noise equivalent count rate (NECR_2R) was 54.7 kcps at 6.0 kBq ml−1. Total sensitivity was 45.2 cps kBq−1 and 48.4 cps kBq−1 at the center and 10 cm off-center FOV, respectively. The TOF and DOI reconstructions significantly improved the image quality in the phantom studies. Moreover, the FL-FIP outperformed the conventional WTA method in terms of the spatial resolution and image quality. Significance. The proposed brain PET scanner could achieve sub-millimeter spatial resolution and high image quality with TOF and DOI reconstruction, which is meaningful to the clinical oncology research. Meanwhile, the comparison among the three positioning methods indicated that the FL-FIP decreased the image degradation caused by Compton scatter more than WTA.
Remote EPID-based dosimetric auditing using DVH patient dose analysis
Authors: Greer P B , Standen T , David R , Miri N , Bobrowski K , Lehmann J , Zwan B , Moore A
Published: December 2022

Objective. The aim of this work was to develop and validate a method for remote dosimetric auditing that enables dose-volume histogram parameter comparisons of measured and planned dose in the patient CT volume. Approach. The method is derived by adapting and combining a remote electronic portal imaging (EPID) based auditing method (Virtual Epid based Standard Phantom Audit—VESPA) and a method to estimate 3D in-patient dose distributions from planar dosimetric measurements. The method was tested with a series of error-induced plans including monitor unit and multileaf collimator (MLC) positioning errors. A pilot audit study was conducted with eleven radiotherapy centres. IMRT plans from two clinical trials, a post-prostatectomy (RAVES trial) plan and a head and neck (HPV trial) plan were utilized. Clinically relevant DVH parameters for the planned dose and estimated measured dose were compared. Main results. The method was found to reproduce the induced dose errors within 0.5% and was sensitive to MLC positioning errors as small as 0.5 mm. For the RAVES plan audit all DVH results except one were within 3% and for the HPV plan audit all DVH results were within 3% except three with a maximum difference of 3.2%. Significance. The results from the audit method produce clinically meaningful DVH metrics for the audited plan and could enable an improved understanding of a centre’s radiotherapy quality.
A dynamic-static combination model based on radiomics features for prostate cancer using multiparametric MRI
Authors: Li Shuqin , Zheng Tingting , Fan Zhou , Qu Hui , Wang Jianfeng , Bi Jianbin , Lv Qingjie , Zhang Gejun , Cui Xiaoyu , Zhao Yue
Published: December 2022

Objective. To propose a new dynamic multiparametric magnetic resonance imaging (mpMRI) radiomics method for the detection of prostate cancer (PCa), and establish a combined model using dynamic and static radiomics features based on this method. Approach. A total of 166 patients (82 PCa patients and 84 non-PCa patients) were enrolled in the study, and 31 872 mpMRI images were performed in a radiomics workflow. The whole prostate segmentation and traditional static radiomics features extraction were performed on intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI, b value of 10, 50, 100, 150, 200, 400, 600, 800, 1000, 1500 s mm−2 respectively), apparent diffusion coefficient (ADC), and T2-weighted imaging (T2WI) sequences respectively. Through the building of each b-value DWI model and the analysis of the static key radiomics features, three types of dynamic features called standard discrete (SD), parameter (P) and relative change rate (RCR) were constructed. And the b-value parameters used to construct dynamic features were divided into three groups (‘Df_’, ‘Db_’ and ‘Da_’): the front part (10–200 s mm−2), the back part (400–1500 s mm−2), and all (10–1500 s mm−2) of the b-values set, respectively. Afterwards, the dynamic mpMRI model and combined model construction were constructed, and the PCa discrimination performance of each model was evaluated. Main results. The models based on dynamic features showed good potential for PCa identification. Where, the results of Db_SD, Da_P and Db_P models were encouraging (test cohort AUCs: 90.78%, 87.60%, 86.3%), which was better than the commonly used ADC model (AUC of ADC was 75.48%). Among the combined models, the models using static features of T2WI and dynamic features performed the best. The AUC of Db_SD + T2WI, Db_P + T2WI and Db_RCR + T2WI model was 92.90%, 91.29% and 81.46%. Significance. The dynamic-static combination model based on dynamic mpMRI radiomics method has a good effect on the identification of PCa. This method has broad application prospects in PCa individual diagnosis management.
Doping dependence of the upper critical field in untwinned YBa2Cu3O

7−δ

thin films
Authors: Wahlberg Eric , Arpaia Riccardo , Kalaboukhov Alexei , Bauch Thilo , Lombardi Floriana
Published: December 2022

We report on measurements of the doping dependence of the upper critical field

H

c
,
2

in 50 nm thick YBa2Cu3O

7
−
δ

films. The films are untwinned and are characterized by a small in-plane compressive strain. We find that the

H

c
,
2

shows a strong decrease in the underdoped region of the phase diagram, in agreement with that which has been measured in relaxed single crystals. The origin of the decrease of

H

c
,
2

in the underdoped regime is discussed within a scenario where charge density wave (CDW) order competes with superconductivity. This demonstrates the potential of using thin films to study the phase diagram of high-T

c
materials under strain, and opens up the possibility for investigating the interplay between CDW order and superconductivity tuned by strain.
Optimization of the structural and optical properties of ALD grown ZnO thin films for photocatalytic applications: thickness dependence
Authors: Shenouda S S , Saif M , Baradács E , Parditka B , Fodor T , Erdélyi Z
Published: December 2022

Thin films of ZnO with different thicknesses (ranging from 8 to 40 nm) have been prepared by plasma-enhanced atomic layer deposition. Grazing incidence x-ray diffraction shows the nano-crystalline structure of the films with high degree of disorder. The films have also lattice oxygen and non-lattice oxygen where the film with 20 nm thickness has the highest percentage of the non-lattice oxygen. These films have indirect optical transitions. The energy gap increases slightly with decreasing the film thickness (2.96, 3.03 and 3.16 eV for the thicknesses 40, 20 and 8 nm, respectively). These films have strong photocatalytic activity to treat the water from the organic dyes such as Levafix Brilliant Red. The film with thickness 20 nm has the optimum photocatalytic activity and the lowest contact angle with water. The photoinduced super-hydrophilic nature of ZnO film (20 nm) renders this film suitable for antifogging application. The high photocatalytic activity and super-hydrophilicity are due to the low recombination rate of charge carriers accompanied to the excess of oxygen vacancies and the high degree of structural disorder.
Probabilities for informational free lunches in stochastic thermodynamics
Authors: Paraguassú Pedro V , Defaveri Lucianno , Duarte Queirós Sílvio M , Morgado Welles A M
Published: December 2022

By considering an explicit nonequilibrium model, we analyze the statistics of the irreversible work, w
irr, and the irreversible entropy production, Δ
i

s, within the stochastic energetics framework. Restating the second law of thermodynamics as a function of w
irr, we introduce the explicit probability of violating the canonical form of that second law for a different set of parameters and initial conditions of the model. Moreover, we study the irreversible entropy production along the same lines, since it can be cast as a generalization of the irreversible work. From an informational perspective, our result allows one to quantify the probability of deleting information without performing work, contrarily to the Landauer’s principle, which we classify as an informational free lunch. We chose for the initial conditions cases of low information content (equilibrium) and high information content (delta distributed).
Beam test performance of a highly granular silicon tungsten calorimeter technical prototype for the ILD
Authors: Morales F Jiménez
Published: December 2022

A highly granular silicon-tungsten electromagnetic calorimeter (SiW-ECAL) is the reference design of the ECAL for International Large Detector concept, one of the two detector concepts for the future International Linear Collider. Prototypes for this type of detector are developed within the CALICE Collaboration. The technological prototype addresses technical challenges such as integrated front-end electronics or compact layer and readout design. A stack of 7 layers was compiled and tested at DESY test beam facilities in 2017. We present preliminary results on the properties of the electromagnetic showers. An outline on the next steps is given. Finally, we illustrate the first steps of the digitization concept on simulations of the prototype.