bluuebunny/crossref_metadata_2025 huggingface dataset:
Utilizing time domain electrical methods to monitor MLCCs' degradation
Authors: Yousefian Pedram , Rajpoot Shalini , Randall Clive A.
Published: March 2023

The continued development of BaTiO3-based multilayer ceramic capacitors has contributed to further miniaturization by reducing the thickness of each dielectric layer for different voltage range components. MLCC designs that achieve higher volumetric capacitive efficiency must be balanced with stable properties over long operational times at higher fields and temperatures, raising concerns about their reliability. To improve the reliability and slow transient mechanisms of oxygen vacancy electromigration that drive the degradation of insulation resistance of MLCCs, we need to develop new models and improved metrologies to enhance the performance of MLCCs. This paper demonstrates how electrical characterization techniques, such as thermally stimulated depolarization current and highly accelerated life test, can be used to better understand MLCCs' degradation and assess their reliability. Also, the limitations of existing lifetime prediction models and their shortcomings of using mean time to failure in predicting the lifetime of MLCCs are discussed along with future perspectives on evaluating the reliability of MLCCs.
Elastic metasurface for flexural wave refraction based on acoustic black hole
Authors: Li Lixia , Su Kun , Liu Haixia , Yang Qian , Li Ling , Xie Miaoxia
Published: March 2023

This letter presents a thin plate structure with an acoustic black hole (ABH) sub-unit to reorient the flexural wave. Different from the previously reported flexural wave metasurface, ABH sub-units are introduced into thin plates in this work, which can control the group velocity of flexural waves and realize their efficient transmission. According to generalized Snell's law, the mechanism of phase shift of transmitted waves across subwavelength sub-units is theoretically revealed. An analysis of the ABH sub-units is established by the finite element method. The deflection and focusing effect of flexural waves are demonstrated. Furthermore, adjusting the black hole section can quickly obtain the transmission phase response in the range of 2π, and it can accurately predict the phase shift and amplitude of the transmitted wave. The results show that the ABH beam-plate structure can effectively control the propagation direction of flexural waves, which provides a modern design idea and method for the manipulation and energy harvesting of the flexural wave.
Substrate-transferred GaAs/AlGaAs crystalline coatings for gravitational-wave detectors
Authors: Cole G. D. , Ballmer S. W. , Billingsley G. , Cataño-Lopez S. B. , Fejer M. , Fritschel P. , Gretarsson A. M. , Harry G. M. , Kedar D. , Legero T. , Makarem C. , Penn S. D. , Reitze D. H. , Steinlechner J. , Sterr U. , Tanioka S. , Truong G.-W. , Ye J. , Yu J.
Published: March 2023

In this Perspective, we summarize the status of technological development for large-area and low-noise substrate-transferred GaAs/AlGaAs (AlGaAs) crystalline coatings for interferometric gravitational-wave (GW) detectors. These topics were originally presented as part of an AlGaAs Workshop held at American University, Washington, DC, from 15 August to 17 August 2022, bringing together members of the GW community from the laser interferometer gravitational-wave observatory (LIGO), Virgo, and KAGRA collaborations, along with scientists from the precision optical metrology community, and industry partners with extensive expertise in the manufacturing of said coatings. AlGaAs-based crystalline coatings present the possibility of GW observatories having significantly greater range than current systems employing ion-beam sputtered mirrors. Given the low thermal noise of AlGaAs at room temperature, GW detectors could realize these significant sensitivity gains while potentially avoiding cryogenic operation. However, the development of large-area AlGaAs coatings presents unique challenges. Herein, we describe recent research and development efforts relevant to crystalline coatings, covering characterization efforts on novel noise processes as well as optical metrology on large-area (∼10 cm diameter) mirrors. We further explore options to expand the maximum coating diameter to 20 cm and beyond, forging a path to produce low-noise mirrors amenable to future GW detector upgrades, while noting the unique requirements and prospective experimental testbeds for these semiconductor-based coatings.
Active topological phase transitions in high-order elastic topological insulators driven by pneumatic methods and liquid metals
Authors: Zhang Hui-Kai , Chen Wei-Tong , Xu Shi-Hao , Wu Jian , Li Bo , Feng Xi-Qiao
Published: March 2023

Active topological phase transitions widely occur in active matters and biological systems, such as developing embryos. Since the discovery of the intriguing bulk-boundary effects of topological insulators in Hermitian and non-Hermitian systems, various electric, optical, acoustic, and mechanical topological metamaterials with efficient energy transmission and robust defect-immunization have been designed. To date, however, it remains a challenge to precisely and fast manipulate the topological phase transitions in elastic topological insulators. In this paper, on the basis of theoretical analysis and numerical simulations, we propose an active strategy to achieve this aim through a combination of pneumatic actuation and liquid metals. The proposed method can precisely tune the connecting stiffness and vertex mass in the tight Su–Schrieffer–Heeger model. Thus, we realize the effective and fast control of topological phase transitions and elastic wave bandgap switching. We also uncover the active spinning bulk-boundary effects and higher-order topological states in the elastic topological insulators, demonstrating the high effectiveness and practicability of the proposed method. In addition, the differences between the 1D edge and 0D corner higher-order states are specified by information entropy theory. This work not only gains insights into the active manipulation of topological phase transitions but also inspires novel strategies to design active topological materials through untethered methods, e.g., magnetism or biological cells.
Performance of a chirped-pulse Fourier transform millimeter wave spectrometer in the range of 75–110 GHz
Authors: Hermanns M. , Wehres N. , Heyne B. , Honingh C. E. , Graf U. U. , Schlemmer S.
Published: March 2023

We present a home-built chirped-pulse Fourier transform millimeter wave (CP-FTMMW) spectrometer. The setup is devoted to the sensitive recording of high-resolution molecular spectroscopy in the W band between 75 and 110 GHz. We describe the experimental setup in detail, including a characterization of the chirp excitation source, the optical beam path, and the receiver. The receiver is a further development of our 100 GHz emission spectrometer. The spectrometer is equipped with a pulsed jet expansion and a DC discharge. Spectra of methyl cyanide as well as hydrogen cyanide (HCN) and hydrogen isocyanide (HNC) products from the DC discharge of this molecule are recorded to characterize the performance of the CP-FTMMW instrument. The formation of the HCN isomer is favored by a factor of 63 with respect to HNC. Hot/cold calibration measurements enable a direct comparison of the signal and noise levels of the CP-FTMMW spectra to those of the emission spectrometer. For the CP-FTMMW instrument, we find many orders of magnitude of signal enhancement and a much stronger noise reduction due to the coherent detection scheme.
The vitality of very-large-scale motions upstream of an overflow structure
Authors: Yan Zili , Zhu Dejun , Li Danxun
Published: March 2023

The flows upstream of a run-of-river dam, commonly utilized as an overflow structure on rivers, are complex due to heterogeneities in both streamwise and spanwise directions. In particular, very-large-scale motions (VLSMs) are greatly influenced by the overflow structure, yet relevant understandings remain limited. Reported as novel coherent structures in turbulent flows, VLSMs are recognized with the scale up to several and tens of the outer-scaled unit, and they contribute significantly to turbulent transport and mixing. To fill the gap, experiments with particle image velocimetry were conducted to investigate the vitality of VLSMs upstream of a model dam. Measurements were designed to cover broad hydraulic scope with flow heterogeneities. The results reveal that VLSMs in the present flow scenario show noticeable characteristics in both streamwise and spanwise directions. Compared to those in uniform flows, the VLSMs in present flows are found to be more energetic and stress-active.
A piezoelectric mechanically coupled Lamé mode resonator with ultra-high Q
Authors: Xiao Yuhao , Han Jinzhao , Zhu Kewen , Wu Guoqiang
Published: March 2023

A piezoelectrically actuated high quality factor (Q) mechanically coupled Lamé mode resonator based on a thin-film piezoelectric-on-silicon (TPoS) platform is demonstrated. The reported coupled resonator consists of two identical square plates of single-crystal silicon (SCS) coupled with a SCS beam having thin-film piezoelectric stacked layers on top. The coupled resonator is piezoelectrically driven into resonance, and the two square plates are excited into vibrations in a coupled Lamé mode through mechanical coupling. An impressive passive Q-enhancement is obtained by such a scheme based on mechanical coupling of two SCS square plates with a piezoelectrically transduced beam. A fabricated mechanically coupled Lamé mode resonator exhibits an ultra-high Q of 309 894 while still maintaining a moderate impedance (Rm) of 6652 Ω at its resonant frequency of 18.2838 MHz, corresponding to the record highest f-Q product of 5.67 × 1012 for TPoS resonators. The reported high Q microelectromechanical system (MEMS) resonator overcomes the inherent low-Q nature of piezoelectric MEMS resonators, indicating an application for providing a high-performance timing solution in a MEMS timing field.
SparseMaps—A systematic infrastructure for reduced-scaling electronic structure methods. VI. Linear-scaling explicitly correlated N-electron valence state perturbation theory with pair natural orbital
Authors: Guo Yang , Pavošević Fabijan , Sivalingam Kantharuban , Becker Ute , Valeev Edward F. , Neese Frank
Published: March 2023

In this work, a linear scaling explicitly correlated N-electron valence state perturbation theory (NEVPT2-F12) is presented. By using the idea of a domain-based local pair natural orbital (DLPNO), computational scaling of the conventional NEVPT2-F12 is reduced to near-linear scaling. For low-lying excited states of organic molecules, the excitation energies predicted by DLPNO-NEVPT2-F12 are as accurate as the exact NEVPT2-F12 results. Some cluster models of rhodopsin are studied using the new algorithm. Our new method is able to study systems with more than 3300 basis functions and an active space containing 12 π-electrons and 12 π-orbitals. However, even larger calculations or active spaces would still be feasible.
A position control method for a robotically assisted magnetic navigation system to improve the pushability of a magnetic catheter by maximizing magnetic force
Authors: Lee D. , Jung E. , Kwon J. , Jang G.
Published: March 2023

We propose a novel position control method (PCM) for the Robotically Assisted MAgnetic Navigation (RAMAN) system to improve the pushability of the magnetic catheter (MC) by maximizing the magnetic force. We expressed the magnetic force acting on the magnetic catheter as the position and the current flowing through each of the electromagnets of the RAMAN system. Next, we formulated a PCM as an optimization problem to maximize the MF. From the proposed PCM, we can determine the position that generates the maximum MF in the desired direction within the region of interest of the RAMAN as well as the required applied current of each electromagnet. Finally, we performed a navigation experiment for the MC along the aorta to the right coronary artery in a cardiac vascular phantom model, and we showed that the proposed PCM can navigate through the vascular phantom effectively without buckling of the MC.
Aquatic biomass is a major source to particulate organic matter export in large Arctic rivers
Authors: Behnke Megan I. , Tank Suzanne E. , McClelland James W. , Holmes Robert M. , Haghipour Negar , Eglinton Timothy I. , Raymond Peter A. , Suslova Anya , Zhulidov Alexander V. , Gurtovaya Tatiana , Zimov Nikita , Zimov Sergey , Mutter Edda A. , Amos Edwin , Spencer Robert G. M.
Published: March 2023

Arctic rivers provide an integrated signature of the changing landscape and transmit signals of change to the ocean. Here, we use a decade of particulate organic matter (POM) compositional data to deconvolute multiple allochthonous and autochthonous pan-Arctic and watershed-specific sources. Constraints from carbon-to-nitrogen ratios (C:N), δ
13
C, and Δ
14
C signatures reveal a large, hitherto overlooked contribution from aquatic biomass. Separation in Δ
14
C age is enhanced by splitting soil sources into shallow and deep pools (mean ± SD: −228 ± 211 vs. −492 ± 173‰) rather than traditional active layer and permafrost pools (−300 ± 236 vs. −441 ± 215‰) that do not represent permafrost-free Arctic regions. We estimate that 39 to 60% (5 to 95% credible interval) of the annual pan-Arctic POM flux (averaging 4,391 Gg/y particulate organic carbon from 2012 to 2019) comes from aquatic biomass. The remainder is sourced from yedoma, deep soils, shallow soils, petrogenic inputs, and fresh terrestrial production. Climate change-induced warming and increasing CO
2
concentrations may enhance both soil destabilization and Arctic river aquatic biomass production, increasing fluxes of POM to the ocean. Younger, autochthonous, and older soil-derived POM likely have different destinies (preferential microbial uptake and processing vs. significant sediment burial, respectively). A small (~7%) increase in aquatic biomass POM flux with warming would be equivalent to a ~30% increase in deep soil POM flux. There is a clear need to better quantify how the balance of endmember fluxes may shift with different ramifications for different endmembers and how this will impact the Arctic system.
Light diffraction by sarcomeres produces iridescence in transmission in the transparent ghost catfish
Authors: Fan Xiujun , Zheng Xuezhi , An Tong , Li Xiuhong , Leung Nathanael , Zhu Bin , Sui Tan , Shi Nan , Fan Tongxiang , Zhao Qibin
Published: March 2023

Despite the elaborate varieties of iridescent colors in biological species, most of them are reflective. Here we show the rainbow-like structural colors found in the ghost catfish (
Kryptopterus vitreolus
), which exist only in transmission. The fish shows flickering iridescence throughout the transparent body. The iridescence originates from the collective diffraction of light after passing through the periodic band structures of the sarcomeres inside the tightly stacked myofibril sheets, and the muscle fibers thus work as transmission gratings. The length of the sarcomeres varies from ~1 μm from the body neutral plane near the skeleton to ~2 μm next to the skin, and the iridescence of a live fish mainly results from the longer sarcomeres. The length of the sarcomere changes by ~80 nm as it relaxes and contracts, and the fish shows a quickly blinking dynamic diffraction pattern as it swims. While similar diffraction colors are also observed in thin slices of muscles from non-transparent species such as the white crucian carps, a transparent skin is required indeed to have such iridescence in live species. The ghost catfish skin is of a plywood structure of collagen fibrils, which allows more than 90% of the incident light to pass directly into the muscles and the diffracted light to exit the body. Our findings could also potentially explain the iridescence in other transparent aquatic species, including the eel larvae (
Leptocephalus
) and the icefishes (Salangidae).
Strain-driven formation of epitaxial nanostructures in brownmillerite strontium cobaltite thin films
Authors: Han Hyeon , Deniz Hakan , Parkin Stuart S. P.
Published: March 2023

Nanostructured materials can display unique physical properties and are of particular interest for their new functionalities. Epitaxial growth is a promising approach for the controlled synthesis of nanostructures with desired structures and crystallinity. SrCoO
x
is a particularly intriguing material owing to a topotactic phase transition between an antiferromagnetic insulating brownmillerite SrCoO
2.5
(BM-SCO) phase and a ferromagnetic metallic perovskite SrCoO
3-δ
(P-SCO) phase depending on the oxygen concentration. Here, we present the formation and control of epitaxial BM-SCO nanostructures by substrate-induced anisotropic strain. Perovskite substrates with a (110)-orientation and which allow for compressive strain result in the creation of BM-SCO nanobars, while (111)-oriented substrates give rise to the formation of BM-SCO nanoislands. We have found that substrate-induced anisotropic strain coupled with the orientation of crystalline domains determines the shape and facet of the nanostructures, while their size can be tuned by the degree of strain. Moreover, the nanostructures can be transformed between antiferromagnetic BM-SCO and ferromagnetic P-SCO via ionic liquid gating. Thus, this study provides insights into the design of epitaxial nanostructures whose structure and physical properties can be readily controlled.
Computational prediction of interactions between Paxlovid and prescription drugs
Authors: Kim Yeji , Ryu Jae Yong , Kim Hyun Uk , Lee Sang Yup
Published: March 2023

Pfizer’s Paxlovid has recently been approved for the emergency use authorization (EUA) from the US Food and Drug Administration (FDA) for the treatment of mild-to-moderate COVID-19. Drug interactions can be a serious medical problem for COVID-19 patients with underlying medical conditions, such as hypertension and diabetes, who have likely been taking other drugs. Here, we use deep learning to predict potential drug–drug interactions between Paxlovid components (nirmatrelvir and ritonavir) and 2,248 prescription drugs for treating various diseases.
Rgs1 is a regulator of effector gene expression during plant infection by the rice blast fungus
Magnaporthe oryzae
Authors: Tang Bozeng , Yan Xia , Ryder Lauren S. , Bautista Mark Jave A. , Cruz-Mireles Neftaly , Soanes Darren M. , Molinari Camilla , Foster Andrew J. , Talbot Nicholas J.
Published: March 2023

To cause rice blast disease, the filamentous fungus
Magnaporthe oryzae
secretes a battery of effector proteins into host plant tissue to facilitate infection. Effector-encoding genes are expressed only during plant infection and show very low expression during other developmental stages. How effector gene expression is regulated in such a precise manner during invasive growth by
M. oryzae
is not known. Here, we report a forward-genetic screen to identify regulators of effector gene expression, based on the selection of mutants that show constitutive effector gene expression. Using this simple screen, we identify Rgs1, a regulator of G-protein signaling (RGS) protein that is necessary for appressorium development, as a novel transcriptional regulator of effector gene expression, which acts prior to plant infection. We show that an N-terminal domain of Rgs1, possessing transactivation activity, is required for effector gene regulation and acts in an RGS-independent manner. Rgs1 controls the expression of at least 60 temporally coregulated effector genes, preventing their transcription during the prepenetration stage of development prior to plant infection. A regulator of appressorium morphogenesis is therefore also required for the orchestration of pathogen gene expression required for invasive growth by
M. oryzae
during plant infection.
Competition between Stepwise Polarization Switching and Chirality Coupling in Ferroelectric GeS Nanotubes
Authors: Wang Hao-Chen , Wang Zhi-Hao , Chen Xuan-Yan , Wei Su-Huai , Zhu Wenguang , Zhang Xie
Published: March 2023

Ferroelectricity of group-IV chalcogenides MX (M = Ge, Sn; X = Se, S) monolayers has been extensively investigated. However, how the ferroelectricity evolves in their one-dimensional nanotubes remains largely unclear. Employing an accurate deep-learning interatomic potential of first-principles precision, we uncover a general stepwise mechanism for polarization switching in zigzag and chiral GeS nanotubes, which has an energy barrier that is substantially lower than the one associated with the conventional one-step switching mechanism. The switching barrier (per atom) gradually decreases with increasing the number of intermediate steps and converges to a value that is almost independent of the tube diameter. In the chiral GeS nanotubes, the switching path of polarization with chirality coupling is preferred at less intermediate steps. This study unveils novel ferroelectric switching behaviors in one-dimensional nanotubes, which is critical to coupling ferroelectricity and chirality.
Vacuum-dual static perfect fluid obeying
p=−(n−3)ρ/(n+1)
in
n(⩾4)
dimensions
Authors: Maeda Hideki
Published: March 2023

We obtain the general

n
(
⩾
4
)

-dimensional static solution with an

(
n
−
2
)

-dimensional Einstein base manifold for a perfect fluid obeying a linear equation of state

p
=
−
(
n
−
3
)
ρ

/

(
n
+
1
)

. It is a generalization of Semiz’s four-dimensional general solution with spherical symmetry and consists of two different classes. Through the Buchdahl transformation, the class-I and class-II solutions are dual to the topological Schwarzschild–Tangherlini-(A)dS solution and one of the Λ-vacuum direct-product solutions, respectively. While the metric of the spherically symmetric class-I solution is

C
∞

at the Killing horizon for n = 4 and 5, it is C
1 for

n
⩾
6

and then the Killing horizon turns to be a parallelly propagated curvature singularity. For n = 4 and 5, the spherically symmetric class-I solution can be attached to the Schwarzschild–Tangherlini vacuum black hole with the same value of the mass parameter at the Killing horizon in a regular manner, namely without a lightlike massive thin-shell. This construction allows new configurations of an asymptotically (locally) flat black hole to emerge. If a static perfect fluid hovers outside a vacuum black hole, its energy density is negative. In contrast, if the dynamical region inside the event horizon of a vacuum black hole is replaced by the class-I solution, the corresponding matter field is an anisotropic fluid and may satisfy the null and strong energy conditions. While the latter configuration always involves a spacelike singularity inside the horizon for n = 4, it becomes a non-singular black hole of the big-bounce type for n = 5 if the ADM mass is larger than a critical value.
Superconductivity in Mo4Ga20As with endohedral gallium clusters
Authors: Ruan Bin-Bin , Chen Le-Wei , Shi Yun-Qing , Yi Jun-Kun , Yang Qing-Song , Zhou Meng-Hu , Ma Ming-Wei , Chen Gen-Fu , Ren Zhi-An
Published: March 2023

We report the discovery and detailed investigation of superconductivity in Mo4Ga20As. Mo4Ga20As crystallizes in a space group of I4/m (No. 87), with the lattice parameters a = 12.86352 Å and c = 5.30031 Å. The resistivity, magnetization, and specific heat data reveal Mo4Ga20As to be a type-II superconductor with T
c = 5.6 K. The upper and lower critical fields are estimated to be 2.78 T and 22.0 mT, respectively. In addition, electron-phonon coupling in Mo4Ga20As is possibly stronger than the BCS weak-coupling limit. First-principles calculations suggest the Fermi level being dominated by the Mo-4d and Ga-4p orbitals.
Remote monitoring method for human body electrostatic potential based on symbolic regression machine learning
Authors: Man Menghua , Wei Ming
Published: March 2023

Remote real-time monitoring of the human body electrostatic potential is of great value to the investigation, analysis, and prevention of electrostatic hazard accidents. The non-contact measurement method inverses the body electrostatic potential by detecting the surrounding electrostatic field. The distribution of electrostatic fields around the human body is easily influenced by the placement of metal equipment and the architectural structure in the application scenario. Therefore, physical modeling-based inversion lacks generality. Field-measured electrostatic signals and symbolic regression machine learning are used to remotely monitor body electrostatic potential. In a 25 m2 laboratory, four non-contact electrostatic sensors, a contact-type body voltage measuring system, and an ultra-wideband positioning system were used to establish the experiment setting. Sixty sets of on-site test data from three participants were used for model training and performance evaluation. The results indicate that the normalized root-mean-square errors of the body electrostatic potential ranged from 0.01 to 0.22. The optimal results satisfy the IEC 61340-4-5:2018 criteria for the precision of the body potential measuring system.
Intelligent fault diagnosis method for rolling bearing using WMNRS and LSSVM
Authors: Bai Xuezong , Zeng Shilong , Ma Qiang , Feng Zihao , An Zongwen
Published: March 2023

A weighted multi-neighborhood rough set (WMNRS) algorithm is designed to resolve the issue in which the neighborhood radius must be adjusted iteratively and cannot be automatically determined in the neighborhood rough set. This algorithm combined with the least squares support vector machines (LSSVM) is used for analyzing rolling bearing condition monitoring data; consequently, an intelligent fault diagnosis method is proposed. Specifically, the time-domain and frequency-domain features are extracted from the collected vibration signals to construct an original feature set. The WMNRS algorithm is then applied to screen the primary sensitive components from the constructed feature set. Finally, an optimized LSSVM is utilized to recognize the fault types. The developed method is validated on a public dataset and a measured rolling bearing dataset. The results demonstrate that the method achieves excellent diagnostic performance. Furthermore, the proposed method has some supremacy regarding running time.
Impacts of respiratory fluctuations on cerebral circulation: a machine-learning-integrated 0–1D multiscale hemodynamic model
Authors: Li Ruichen , Sughimoto Koichi , Zhang Xiancheng , Wang Sirui , Liu Hao
Published: March 2023

Objective. This study aims to accurately identify the effects of respiration on the hemodynamics of the human cardiovascular system, especially the cerebral circulation. Approach: we have developed a machine learning (ML)-integrated zero–one-dimensional (0–1D) multiscale hemodynamic model combining a lumped-parameter 0D model for the peripheral vascular bed and a one-dimensional (1D) hemodynamic model for the vascular network. In vivo measurement data of 21 patients were retrieved and partitioned into 8000 data samples in which respiratory fluctuation (RF) of intrathoracic pressure (ITP) was fitted by the Fourier series. ML-based classification and regression algorithms were used to examine the influencing factors and variation trends of the key parameters in the ITP equations and the mean arterial pressure. These parameters were employed as the initial conditions of the 0–1D model to calculate the radial artery blood pressure and the vertebral artery blood flow volume (VAFV). Main results: during stable spontaneous respiration, the VAFV can be augmented at the inhalation endpoints by approximately 0.1 ml s−1 for infants and 0.5 ml s−1 for adolescents or adults, compared to those without RF effects. It is verified that deep respiration can further increase the ranges up to 0.25 ml s−1 and 1 ml s−1, respectively. Significance. This study reveals that reasonable adjustment of respiratory patterns, i.e. in deep breathing, enhances the VAFV and promotes cerebral circulation.
Optical tunable multifunctional applications based on graphene metasurface in terahertz
Authors: Xu Hui , Li Ming , Chen Zhiquan , He Longhui , Dong Yulan , Li Xuelei , Wang Xiaojing , Nie Guozheng , He Zhihui , Zeng Biao
Published: March 2023

Due to the superior properties of graphene and the application potential of surface plasmons, the research of graphene surface plasmons has become a hot research direction. Based on the surface plasmons of graphene, this paper has done some researches on the plasma induced transparency, absorption, and slow light effect. The main work and results of this paper are as follows: we have designed a graphene-based metamaterial structure that can realize a dual plasma induced transparency (PIT) effect. The specific structure is formed by the periodic arrangement of graphene bands (as bright mode) and band edge microchips (as bright mode). We use the finite-difference time-domain (FDTD) method to study the dual PIT effect from the aspect of numerical simulation, and then further study the phenomenon of this device from the theoretical fitting of the coupled mode theory (CMT). The CMT model explores the physical mechanism of dual PIT spectral line and obtains a good fitting result. By studying the formation mechanism of the dual PIT effect, we have found that the graphene band as a bright mode interacts with the band edge microchip as a dark mode, and then the dual PIT is formed by destructive interference of the bright and dark modes. In order to better external modulation, the structure only studies the modulation effect caused by the change of Fermi level affected by the external voltage of graphene. Moreover, we also have studied the slow light performance of this structure, and the slow light coefficient reached 0.236 picoseconds (ps). This proposed coupling system of dual PIT effect has important research significance in optical switches, optical loop, and slow light devices.
Observation of improved confinement by non-axisymmetric magnetic field in KSTAR
Authors: Kim Kimin , Kang Jisung , Kim Hyunseok , Yi Sumin , Yoo Jeongwon , Choi Minjun , Rhee Tongnyeol , Kim Junghee , Lee Myungwon , Ko Won-Ha , Kwon Jaemin
Published: March 2023

We report the observation of improved confinement discharge in a magnetic braking experiment in the KSTAR tokamak. The improved confinement is achieved with reduced toroidal plasma rotation by non-axisymmetric magnetic field induced toroidal rotation braking along with significant reduction of edge localized modes (ELMs). Modifications in multi-channel transport raise fast ion slowing-down time and improve neutral beam deposition, leading to improved fast ion confinement. We show that modifications of radial electric field and E × B shear flow by magnetic braking provoke an enhanced pedestal to sustain thermal confinement against degradation in the typical 3D field experiment.
Innovative research and development activities on high energy and high current isochronous proton accelerator
Authors: Zhang Tianjue , Fu Wei , Wang Chuan , Pei Shilun , Yin Zhiguo , Zhou Hongji , Yin Ziye , Zhang Suping , Liu Jingyuan , Zhu Xiaofeng , Wang Fei , Wang Yang , Cai Hongru , Pan Gaofeng , Mu Xueer , Lin Jun , Zhao Bohan , He Aolai , Chu Zhichao , Hu Mingzhi , Song Qiqi
Published: March 2023

The MW class proton accelerators are expected to play
important roles in many fields, attracting institutions to continue
researching and tackling key problems. The continuous wave (CW)
isochronous accelerator obtains a high-power beam with higher energy
efficiency, which is very attractive to many applications. Scholars
generally believe that the energy limitation of the isochronous
cyclotron is ∼1 GeV. To get higher beam power by the
isochronous machine, enhancing the beam focusing become the most
important issue.

Adjusting the radial gradient of the average magnetic field makes
the field distribution match the isochronism. When we adjust the
radial gradient of the peak field, the first-order gradient is
equivalent to the quadrupole field, the second-order, the hexapole
field, and so on. Just like the synchrotron, there are quadrupoles,
hexapole magnets, and so on, along the orbits to get higher energy,
as all we know.

If we adjust the radial gradient for the peak field of an FFA's FDF
lattice and cooperate with the angular width (azimuth flutter) and
spiral angle (edge focusing) of the traditional cyclotron pole, we
can manipulate the working path in the tune diagram very
flexibly. During enhancing the axial focusing, both the beam
intensity and the energy of the isochronous accelerator are
significantly increased. Here a 2 GeV CW FFA with 3 mA of average
beam intensity design is presented. It is essentially an isochronous
cyclotron although we use 10 FDF lattices. The key difficulty is
that the magnetic field and each order of gradient should be
accurately adjusted in a large radius range.

As a high-power proton accelerator with high energy efficiency, we
adopt high-temperature superconducting (HTS) technology for the
magnets. 15 RF cavities with a Q value of 90000 provide energy gain
per turn of ∼15 MeV to ensure the CW beam intensity reaches 3
mA. A 1:4 scale, 15-ton HTS magnet, and a 1:4 scale, 177 MHz cavity
have been completed. The results of such R&D will also be presented
in this paper.
Status update of the Charge Stripper Rings project
Authors: Imao H.
Published: March 2023

The RIKEN RI (radioactive isotope) Beam Factory (RIBF)
provides the world's most intense heavy ion beams exceeding
345 MeV/u and is the primary facility for in-flight RI beam
generation. The RIBF has steadily improved its performance. In
particular, the intensity of the uranium beam, which is critical for
producing in-flight fission RI beams, has been dramatically
increased by a factor of 240 compared to 2008. To further increase
the intensity of the uranium beam, a new acceleration scheme using
charge stripper rings (CSRs) has been proposed as a cost-effective
way to increase charge stripping efficiency. In this paper, we
discuss the key design issues of CSR and required upgrades of
existing ring cyclotrons with the introduction of CSR and
space-charge effects.
Examining the spatially varying and interactive effects of green and blue space on health outcomes in Northern Ireland using multiscale geographically weighted regression modeling
Authors: Wang Ruoyu , Grekousis George , Maguire Aideen , McKinley Jennifer M , Garcia Leandro , Rodgers Sarah E , Hunter Ruth F
Published: March 2023

Previous studies have mainly examined the independent effects of green or blue space on health from a perspective of spatial homogeneity, which neglects their interactive or spatially varying effects. Here, we examined the spatially varying and interactive effects of green and blue space on health using open access data in Northern Ireland (NI). Aggregate health data was collected from 2017 Northern Ireland Multiple Deprivation Measure at the Super Output Area (SOA) level. Green and blue spaces were extracted from Land Cover Map data. The proportion of grassland and the proportion of woodland for each SOA were calculated as proxies for green space, while the proportion of water bodies was calculated for measuring blue space. Spatially varying effects of green and blue space were modelled using multiscale Geographic Weighted Regression (MGWR). Interaction terms between green and blue spaces were added into the MGWR models to test the interactive association of green and blue space on different health outcomes (e.g., preventable death ratio and cancer registrations). Results indicate that associations were distributed zonally, with green and blue spaces in eastern areas of NI more strongly associated with health outcomes than in western areas. Within these large regional zones, further spatially varying effects of different green and blue spaces were observed. Grassland was generally positively associated with some health outcomes (e.g., less preventable death ratio, cancer registrations ratio, multiple prescriptions ratio, and long-term health problem or disability ratio), while the results of woodland and water body were mixed. Water bodies were found to strengthen the effect of woodland and grassland. The above results indicate that green and blue space have independently and interactive spatially varying associations with different health outcomes in NI. It is also important to combine both green and blue space elements to enhance health impacts in future interventions.
Breast Explantation With Simultaneous Mastopexy and Volume Restoration: An Analysis of Clinical Outcomes and Prospective Quality of Life
Authors: Messa Charles A , Messa Charles A
Published: March 2023

Background

An increasing number of patients are undergoing explantation to alleviate symptoms attributed to the presence of a prothesis or dissatisfaction with the appearance of their breasts.

Objectives

The authors aim to evaluate the clinical effectiveness and quality of life (QoL) of simultaneous explantation, capsulectomy, and mastopexy for patients requesting implant removal.

Methods

Two hundred sixty-two simultaneous explantation, capsulectomy, and mastopexy (ECM) procedures were performed in 131 patients from 2009 to 2019. Prospective QoL assessment was administered for all patients. Inclusion criteria included a minimum postoperative follow-up of 6 months and completion of a practice-generated patient reported outcomes (PRO) questionnaire. Wilcoxon signed-rank test was performed to compare changes in QoL scores.

Results

Mean follow-up and BMI were 23 months (6 months to 8 years) and 24.8 kg/m2 (18–34 kg/m2), respectively. Mean age was 48.3 years (26–75 years). Autologous fat grafting was performed simultaneously in patients 47.3% (n = 62). The complication rate was 3.8% (n = 10 breasts) in 9 patients (6.9%). The overall reoperation rate was 7.3% of procedures (n = 19 breasts) and 9.2% of patients (n = 12), including secondary autologous fat grafting (11.3%, n = 7). PRO results demonstrated a significant improvement in all QoL domains, including physical well-being (P < .005), psychological well-being (P < .005), sexual well-being (P < .005), breast shape (P < .005), and breast appearance (P < .005). With respect to breast implant illness symptoms, 59 patients (88.1%) noted reduced pain, myalgias/arthralgias, and fatigue after ECM.

Conclusions

This study presents an effective paradigm to manage implant removal through simultaneous explantation, capsulectomy, and mastopexy with acceptable clinical outcomes and a significant improvement in QoL and breast aesthetics.

Level of Evidence: 4
miWords: transformer-based composite deep learning for highly accurate discovery of pre-miRNA regions across plant genomes
Authors: Gupta Sagar , Shankar Ravi
Published: March 2023

Discovering pre-microRNAs (miRNAs) is the core of miRNA discovery. Using traditional sequence/structural features, many tools have been published to discover miRNAs. However, in practical applications like genomic annotations, their actual performance has been very low. This becomes more grave in plants where unlike animals pre-miRNAs are much more complex and difficult to identify. A huge gap exists between animals and plants for the available software for miRNA discovery and species-specific miRNA information. Here, we present miWords, a composite deep learning system of transformers and convolutional neural networks which sees genome as a pool of sentences made of words with specific occurrence preferences and contexts, to accurately identify pre-miRNA regions across plant genomes. A comprehensive benchmarking was done involving >10 software representing different genre and many experimentally validated datasets. miWords emerged as the best one while breaching accuracy of 98% and performance lead of ~10%. miWords was also evaluated across Arabidopsis genome where also it outperformed the compared tools. As a demonstration, miWords was run across the tea genome, reporting 803 pre-miRNA regions, all validated by small RNA-seq reads from multiple samples, and most of them were functionally supported by the degradome sequencing data. miWords is freely available as stand-alone source codes at https://scbb.ihbt.res.in/miWords/index.php.
Timing of symptomatic venous thromboembolism after surgery: meta-analysis
Authors: Singh Tino , Lavikainen Lauri I , Halme Alex L E , Aaltonen Riikka , Agarwal Arnav , Blanker Marco H , Bolsunovskyi Kostiantyn , Cartwright Rufus , García-Perdomo Herney , Gutschon Rachel , Lee Yung , Pourjamal Negar , Vernooij Robin W M , Violette Philippe D , Haukka Jari , Guyatt Gordon H , Tikkinen Kari A O
Published: March 2023

Background

The timing at which venous thromboembolism (VTE) occurs after major surgery has major implications for the optimal duration of thromboprophylaxis. The aim of this study was to perform a systematic review and meta-analysis of the timing of postoperative VTE up to 4 weeks after surgery.

Methods

A systematic search of MEDLINE, Scopus, and CINAHL databases was performed between 1 January 2009 and 1 April 2022. Prospective studies that recruited patients who underwent a surgical procedure and reported at least 20 symptomatic, postoperative VTE events by time were included. Two reviewers independently selected studies according to the eligibility criteria, extracted data, and evaluated risk of bias. Data were analysed with a Poisson regression model, and the GRADE approach was used to rate the certainty of evidence.

Results

Some 6258 studies were evaluated, of which 22 (11 general, 5 urological, 4 mixed, and 2 orthopaedic postoperative surgical populations; total 1 864 875 patients and 24 927 VTE events) were eligible. Pooled evidence of moderate certainty showed that 47.1 per cent of the VTE events occurred during the first, 26.9 per cent during the second, 15.8 per cent during the third, and 10.1 per cent during the fourth week after surgery. The timing of VTE was consistent between individual studies.

Conclusion

Although nearly half of symptomatic VTE events in first 4 weeks occur during the first postoperative week, a substantial number of events occur several weeks after surgery. These data will inform clinicians and guideline developers about the duration of postoperative thromboprophylaxis.
Biomechanical induction of mild brain trauma in larval zebrafish: effects on visual startle reflex habituation
Authors: Beppi Carolina , Penner Marco , Straumann Dominik , Bögli Stefan Yu
Published: March 2023

A mild traumatic brain injury is a neurological disturbance of transient or/and chronic nature after a direct blow of the head/neck or exposure of the body to impulsive biomechanical forces, indirectly affecting the brain. The neuropathological events leading to the clinical signs, symptoms and functional disturbances are still elusive due to a lack of sensitive brain-screening tools. Animal models offer the potential to study neural pathomechanisms in close detail. We recently proposed a non-invasive protocol for inducing concussion-like symptoms in larval zebrafish via exposure to rapid linearly accelerating–decelerating body motion. By mean of auditory ‘startle reflex habituation’ assessments—an established neurophysiological health index—we probed acute and chronic effects that mirror human concussion patterns. This study aimed at expanding our previous work by assessing the ensuing effects with visual—as opposed to auditory—‘startle reflex habituation’ quantifications, by using the same methodology. We observed that immediately after impact exposure, the fish showed impaired sensory reactivity and smaller decay constant, possibly mirroring acute signs of confusion or loss of consciousness in humans. By 30-min post-injury, the fish display temporary signs of visual hypersensitivity, manifested as increased visuomotor reactivity and a relatively enlarged decay constant, putatively reflecting human post-concussive sign of visual hypersensitivity. In the following 5–24 h, the exposed fish progressively develop chronic signs of CNS dysfunction, in the form of low startle responsivity. However, the preserved decay constant suggests that neuroplastic changes may occur to restore CNS functioning after undergoing the ‘concussive procedure’. The observed findings expand our previous work providing further behavioural evidence for the model. Limitations that still require addressment are discussed, advancing further behavioural and microscopic analyses that would be necessary for the validation of the model in its putative relatability with human concussion.
RSL1D1 knockdown induces ferroptosis and mediates ferrous iron accumulation in senescent cells by inhibiting FTH1 mRNA stability
Authors: Jin Yu , Zhao Lei , Wang Shuhao , Zhang Xianglan , Quan Jishu , Lin Zhenhua , Piao Junjie
Published: March 2023

Iron metabolism plays an important role in maintaining cellular multiple biological functions. Dysfunction of iron homeostasis-maintaining systems was observed in many diseases, including cancer. Ribosomal L1 domain-containing 1 (RSL1D1) is an RNA-binding protein involved in multiple cellular processes, including cellular senescence, proliferation and apoptosis. However, the regulatory mechanism of RSL1D1 underlying cellular senescence and its biological process in colorectal cancer (CRC) is not clearly understood. Here, we report that RSL1D1 expression is downregulated by ubiquitin-mediated proteolysis in senescence-like CRC cells. RSL1D1, as an anti-senescence factor, is frequently upregulated in CRC, and elevated RSL1D1 prevents CRC cells from senescence-like phenotype, and correlated with poor prognosis of CRC patients. Knockdown of RSL1D1 inhibited cell proliferation, and induced cell cycle arrest and apoptosis. Notably, RSL1D1 plays important roles in regulating iron metabolism of cancer cells. In RSL1D1-knockdown cells, FTH1 expression was significantly decreased, while transferrin receptor 1 expression was increased, leading to intracellular ferrous iron accumulation, which subsequently promoted ferroptosis, indicated by the increased malondialdehyde and decreased GPX4 levels. Mechanically, RSL1D1 directly bounds with 3ʹ untranslated region of FTH1 and subsequently promoted the mRNA stability. Moreover, RSL1D1-mediated downregulation of FTH1 was also observed in H2O2-induced senescence-like cancer cells. Taken together, these findings support RSL1D1 plays an important role in regulating intracellular iron homeostasis in CRC, and suggest that RSL1D1 could be a potential therapeutic target for cancer treatment.
Concurrent Determination of Pridinol, Diclofenac and Impurity A by HPLC-UV
Authors: Rodríguez-Basso Ángeles Gloria , Bonafede Silvina Laura , Prado Héctor Juan
Published: March 2023

A reversed-phase high-performance liquid chromatography method was developed and validated for the simultaneous determination of pridinol, diclofenac and diclofenac-related compounds in tablet formulations. The proposed method is also suitable for content uniformity determination, for dissolution test and for stability studies. Separation was achieved on a base-deactivated silica C8 column, using 50 mM phosphate buffer (pH 2.5) and methanol (40:60 v/v) as mobile phase, at a flow rate of 1.0 mL/min and column temperature of 40°C. Ultraviolet detection was made at 225 nm. The method was validated for specificity, accuracy, precision (intraday and interday levels) and linearity for each analyte. For diclofenac impurity A, sensitivity was also studied. The method showed specificity and linearity (R2: 0.999 for the three analytes) over the assessed concentration range (diclofenac: 2.5–75.0 μg/mL, pridinol: 2.0–60.0 μg/mL and impurity A: 1.25–5.0 μg/mL) and demonstrated good precision as reflected by the low coefficient of variation in all cases. Recovery rates obtained were 99.81, 100.58 and 100.96% for diclofenac, pridinol and impurity A respectively, and for all three analytes, the variances of the concentrations tested were equivalent. The detection and quantitation limits for impurity A were 0.078 and 0.261 μg/mL, respectively.