bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of electric polarization and defect energy levels induced by ion irradiation on the electrical behavior of 4H-SiC Schottky barrier diodes
Authors: Tian Yinan , Li Ronghua , Li Jian , Li Haixia , Zheng Xuefeng , Cheng Zhaoyi , Sun Jianrong
Published: May 2023

The effects of electric polarization and defect energy levels induced by C4+ irradiation on the electrical behavior of 4H-SiC Schottky barrier diodes (SBDs) are discussed. The parameters of the SBDs were extracted from capacitance–voltage (C–V) and current–voltage (I–V) measurements, the deep level transient spectroscopy (DLTS) was used to identify defect energy levels. In addition, the dielectric function and energy band structure of 4H-SiC were calculated using a first-principles approach to verify the enhancement of polarization and the origin of the defect energy levels. The results show that the net (donor) carrier concentration (N
d) increases with the increase of irradiation fluence, which is caused by the competition between irradiation-induced defects and the polarization effect. On the one hand, Z
1/2 is determined by DLTS. It is related to the doubly negatively (2-|0) charged state of V
c (carbon vacancy), which is a double acceptor. The intensity of the Z
1/2 peak increases with increasing irradiation fluence, which means that the defects caused by irradiation should reduce the N
d. On the other hand, the polarization effect does exist and it becomes stronger with the increase in the irradiation fluence, which makes the N
d increase. Obviously, the polarization effect induced by the irradiation is dominant for N
d when the depth of ion penetration is in the shallow layer behind the metal–semiconductor (M–S) interface. Irradiation induced electron traps and an uneven distribution of positively charged centers, which can cause ln(I)-V to exhibit a non-linear component before reaching the turn-on voltage. The series resistance (R
s), reverse current (I
R) increase and the forward current decreases with the increase in irradiation fluence. All these show that the irradiation causes degradation of Ni/4H-SiC SBD performance.
Boron nitride nanotube peapods at ultrasonic velocity impacts: a fully atomistic molecular dynamics investigation
Authors: De Sousa J M , Machado L D , Woellner C F , Medina M , Autreto P A S , Galvão D S
Published: May 2023

Boron nitride nanotube peapods (BNNT-peapod) are composed of linear chains of C60 molecules encapsulated inside BNNTs, they were first synthesized in 2003. In this work, we investigated the mechanical response and fracture dynamics of BNNT-peapods under ultrasonic velocity impacts (from 1 km s−1 up to 6 km s−1) against a solid target. We carried out fully atomistic reactive molecular dynamics simulations using a reactive force field. We have considered the case of horizontal and vertical shootings. Depending on the velocity values, we observed tube bending, tube fracture, and C60 ejection. Furthermore, the nanotube unzips for horizontal impacts at certain speeds, forming bi-layer nanoribbons ‘incrusted’ with C60 molecules. The methodology used here is applicable to other nanostructures. We hope it motivates other theoretical investigations on the behavior of nanostructures at ultrasonic velocity impacts and aid in interpreting future experimental results. It should be stressed that similar experiments and simulations were carried out on carbon nanotubes trying to obtain nanodiamonds. The present study expands these investigations to include BNNT.
Optical fiber Bragg grating based sensing system of flexible wearable smart sleeve for tracking human arm joint movements
Authors: Feng Yan , Wang Hao-xiang , Liu Peng-bin , Qi Hua , Pan Rui-zhi , Zhang Hong-pu , Zhang Hua
Published: May 2023

Optical fiber Bragg sensors (FBGs) have great potential in the field of flexible wearable devices for tracking human gestures. Due to different human sizes, different wearable tensions inevitably cause errors when tracking arm joint movements. We have designed a flexible wearable smart sleeve with four heads of FBG and spandex polyurethane fibers (SPFs). SPFs sewn with flexible fabric sleeves convert elbow yawing and wrist pitching and roll into an axial strain of FBG. The measuring system has been developed to deduce personalized sensitivity using a dynamic calibration method. For males and females, dynamic calibration, verification and tracking tests were carried out. From the male’s experimental data, the relative errors between the verification sensitivity and the personalized sensitivity are 1.93%, 5.85% and 7.16%, and the average relative errors between the tracking sensitivity and the personalized sensitivity are 7.09%, 5.58% and 2.52%, respectively. And from the data of the female’s experiment, the relative errors between the verification sensitivity and the personalized sensitivity are 0.25%, 5.0% and 6.75%, and the average relative errors between the tracking sensitivity and the personalized sensitivity are 0.99%, 5.56% and 6.95%, respectively. The experimental data have shown that this wearable smart sleeve and the measuring system work well. The research results can be used to develop FBG sensing systems for monitoring joint movements for different human sizes on-line.
State-of-the-art mental tasks classification based on electroencephalograms: a review
Authors: Saini M , Satija U
Published: May 2023

Electroencephalograms (EEGs) play an important role in analyzing different mental tasks and neurological disorders. Hence, they are a critical component for designing various applications, such as brain–computer interfaces, neurofeedback, etc. Mental task classification (MTC) is one of the research focuses in these applications. Therefore, numerous MTC techniques have been proposed in literary works. Although various literature reviews exist based on EEG signals for different neurological disorders and behavior analysis, there is a lack of reviews of state-of-the-art MTC techniques. Therefore, this paper presents a detailed review of MTC techniques, including the classification of mental tasks and mental workload. A brief description of EEGs along with their physiological and nonphysiological artifacts is also presented. Furthermore, we include information on several publicly available databases, features, classifiers, and performance metrics used in MTC studies. We implement and evaluate some of the commonly used existing MTC techniques in the presence of different artifacts and subjects, based on which the challenges and directions are highlighted for future research in MTC.
Surface defects in 4H-SiC: properties, characterizations and passivation schemes
Authors: Mao Weiwei , Cui Can , Xiong Huifan , Zhang Naifu , Liu Shuai , Dou Maofeng , Song Lihui , Yang Deren , Pi Xiaodong
Published: May 2023

Silicon carbide (SiC) is a typical wide band-gap semiconductor material that exhibits excellent physical properties such as high electron saturated drift velocity, high breakdown field, etc. The SiC material contains many polytypes, among which 4H-SiC is almost the most popular polytype as it possesses a suitable band-gap and high electron saturated drift velocity. In order to produce 4H-SiC power devices with a high barrier voltage of over several thousand volts, the minority carrier lifetime of 4H-SiC single crystals must be carefully managed. In general, both bulk defects and surface defects in 4H-SiC can reduce the minority carrier lifetime. Nevertheless, as surface defects have received less attention in publications, this study reviews surface defects in 4H-SiC. These defects can be classified into a number of categories, such as triangle defect, pit, carrot, etc. This paper discusses each one individually followed by the introduction of industrially feasible methods to characterize them. Following this, the impact of surface defects on the minority carrier lifetime is analyzed and discussed. Finally, a particular emphasis is put on discussing various passivation schemes and their effects on the minority carrier lifetime of 4H-SiC single crystals. Overall, this review paper aims to help young researchers comprehend surface defects in 4H-SiC single crystal material.
Cross-linked self-healing polymers containing rosin moiety based on dynamic urea and multiple hydrogen bonds
Authors: Lu Liwei , Yu Caili , Zhou Zhongqun , Zhang Faai
Published: May 2023

In recent years, the use of renewable biomass resources to prepare self-healing polymers has become a hot research topic because of the shortage of fossil resources. Herein, a novel type of rosin-based cross-linked polymer (PR) with dynamic urea and multiple hydrogen bonds is fabricated by copolymerizing a rosin ester with a dynamic crosslinking agent poly(urethane-urea) through a simple UV-initiated reaction. Owing to its robustly dynamic bonds, the resulting PR has both good mechanical properties and ideal self-healing ability. Specifically, the PR with 25.4% biomass rosin reaches a tensile strength of up to 4.1 MPa, an elongation at break of 112%, and stress self-healing efficiency of 91.3% at 80 °C for 24 h. Remarkably, the PR with a glass transition temperature above room temperature exhibits good shape memory behavior and excellent weldability (afford 2500 g after healing at 80 °C for 5 h). Finally, by surface platinum spraying and pre-stretching treatment, strain sensors based on microcracking mechanisms are realized.
Robust two-qubit gates using pulsed dynamical decoupling
Authors: Barthel Patrick , Huber Patrick H , Casanova Jorge , Arrazola Iñigo , Niroomand Dorna , Sriarunothai Theeraphot , Plenio Martin B , Wunderlich Christof
Published: May 2023

We present the experimental implementation of a two-qubit phase gate, using a radio frequency (RF) controlled trapped-ion quantum processor. The RF-driven gate is generated by a pulsed dynamical decoupling sequence applied to the ions’ carrier transitions only. It allows for a tunable phase shift with high-fidelity results. The conditional phase shift is measured using a Ramsey-type measurement with an inferred fringe contrast of up to

99

−
2

+
1

%

. We also prepare a Bell state using this laser-free gate. The phase gate is robust against common sources of error. We investigate the effect of the excitation of the center-of-mass (COM) mode, errors in the axial trap frequency, pulse area errors and errors in sequence timing. The contrast of the phase gate is not significantly reduced up to a COM mode excitation

<

20 phonons, trap frequency errors of +10%, and pulse area errors of −8%. The phase shift is not significantly affected up to

<

10 phonons and pulse area errors of −2%. Both, contrast and phase shift are robust to timing errors up to −30% and +15%. The gate implementation is resource efficient, since only a single driving field is required per ion. Furthermore, it holds the potential for fast gate speeds (gate times on the order of 100 µs) by using two axial motional modes of a two-ion crystal through improved setups.
Diagnosis of fast electron transport by coherent transition radiation
Authors: Liu Yangchun , Ning Xiaochuan , Wu Dong , Liang Tianyi , Liu Peng , Liu Shujun , Liu Xu , Sheng Zhengmao , Hong Wei , Gu Yuqiu , He Xiantu
Published: May 2023

Transport of fast electrons in overdense plasmas is of key importance in high energy density physics. However, it is challenging to diagnose the fast electron transport in experiments. In this article, we study coherent transition radiation (CTR) generated by fast electrons on the back surface of the target by using 2D and 3D first-principle particle-in-cell (PIC) simulations. In our simulations, aluminum targets of 2.7 g cc−1 are simulated in two different situations by using a newly developed high order implicit PIC code. Comparing realistic simulations containing collision and ionization effects, artificial simulations without taking collision and ionization effects into account significantly underestimate the energy loss of electron beams when transporting in the target, which fail to describe the complete characteristics of CTR produced by electron beams on the back surface of the target. Realistic simulations indicate the diameter of CTR increases when the thickness of the target is increased. This is attributed to synergetic energy losses of high flux fast electrons due to Ohm heating and colliding drags, which appear quite significant even when the thickness of the solid target only differs by micrometers. Especially, when the diagnosing position is fixed, we find that the intensity distribution of the CTR is also a function of time, with the diameter increased with time. As the diameter of CTR is related to the speed of electrons passing through the back surface of the target, our finding may be used as a new tool to diagnose the electron energy spectra near the surface of solid density plasmas.
Visually meaningful image encryption combining with reversible data hiding in encrypted images
Authors: Liu Zhaoyang , Xue Ru
Published: May 2023

At present, most image encryption schemes directly change plaintext images into ciphertext images without visual significance, such ciphertext images can be detected and therefore subject to various attacks. To protect the content security and visual safety of images, a visually meaningful image encryption (VMIE) algorithm combining with Reversible Data Hiding in Encrypted Images (RDHEI) is proposed. First, the secret image is encrypted and additional information is embedded by Chen hyperchaotic system and prediction error expansion (PEE) method. Then the source image is encrypted by a Lorentz hyperchaotic system. Finally, bit-xor operation is performed on the resulting encrypted image and the result is saved in a cloud database to generate an indexing key using SHA-256,which enables the receiver to recover the secret image with the resource image and the key alone. The scheme combines with the RDHEI, improving the transmission efficiency and has no image quality problems.The experimental results and security analysis show that the image encryption scheme has sufficient key space, strong key sensitivity and wide applicability.
Cosmic acceleration with bulk viscosity in an anisotropic f(R, L

m
) background
Authors: Solanki Raja , Patel Bina , Jaybhaye Lakhan V , Sahoo P K
Published: May 2023

In this article, we investigate the observed cosmic acceleration in the framework of a cosmological f(R, L

m
) model dominated by bulk viscous matter in an anisotropic background. We consider the locally rotationally symmetric Bianchi type I metric and derive the Friedmann equations that drive the gravitational interactions in f(R, L

m
) gravity. Further, we assume the functional form

f
(
R
,

L

m

)
=

R

2

+

L

m

α

, where α is a free model parameter, and then find the exact solutions of field equations corresponding to our viscous matter dominated model. We incorporate the updated H(z) data and the Pantheon data to acquire the best-fit values of parameters of our model by utilizing the χ
2 minimization technique along with the Markov Chain Monte Carlo random sampling method. Further, we present the behavior of physical parameters that describe the Universe’s evolution phase, such as density, effective pressure and EoS parameters, skewness parameter, and the statefinder diagnostic parameters. We find that the energy density indicates expected positive behavior, whereas the negative behavior of bulk viscous pressure contributes to the Universe’s expansion. The effective EoS parameter favors the accelerating phase of the Universe’s expansion. Moreover, the skewness parameter shows the anisotropic nature of spacetime during the entire evolution phase of the Universe. Finally, from the statefinder diagnostic test, we found that our cosmological f(R, L

m
) model lies in the quintessence region, and it behaves like a de-Sitter universe in the far future. We analyze different energy conditions in order to test the consistency of the obtained solution. We find that all energy conditions except strong energy condition (SEC) show positive behavior, while the violation of SEC favors the recently observed acceleration with the transition from decelerated to an accelerated epoch of the Universe’s expansion in the recent past.
Magnetic and electronic properties of bulk and two-dimensional FeBi2Te4: A first-principles study
Authors: Wang Qianqian , Zhao Jianzhou , Wu Weikang , Zhou Yinning , Li Qile , Edmonds Mark T. , Yang Shengyuan A.
Published: May 2023

Layered magnetic materials, such as MnBi2Te4, have drawn much attention owing to their potential for realizing two-dimensional (2D) magnetism and possible topological states. Recently, FeBi2Te4, which is isostructural to MnBi2Te4, has been synthesized in experiments, but its detailed magnetic ordering and band topology have not been clearly understood yet. Here, based on first-principles calculations, we investigate the magnetic and electronic properties of FeBi2Te4 in bulk and 2D forms. We show that different from MnBi2Te4, the magnetic ground states of bulk, single-layer, and bilayer FeBi2Te4 all favor a 120° noncollinear antiferromagnetic ordering, and they are topologically trivial narrow-gap semiconductors. For the bilayer case, we find that a quantum anomalous Hall effect with a unit Chern number is realized in the ferromagnetic state, which may be achieved in experiment by an external magnetic field or by magnetic proximity coupling. Our work clarifies the physical properties of the new material system of FeBi2Te4 and reveals it as a potential platform for studying magnetic frustration down to 2D limit as well as quantum anomalous Hall effect.
Effects of Cu and Co additions on the crystallization and magnetic properties of FeNbB alloy
Authors: Yu Wan-Qiu , Tian Bo , Zhang Ping-Li , Wang Jia-Hui , Hua Zhong
Published: May 2023

The nanocrystalline-forming element Cu and magnetic element Co are commonly used as additive elements to tune the structure and improve the properties of alloys. In this study, four kinds of amorphous alloys, Fe72Nb12B16, Fe72Nb12B15Cu1, Fe36Co36Nb12B16, and Fe36Co36Nb12B15Cu1, were prepared by melt-spinning and annealed at various temperatures to investigate the effects of Cu and Co additions, individually and in combination, on the crystallization and magnetic properties of Fe72Nb12B16 alloy. The four kinds of alloys exhibited different crystallization behaviors with different primary crystallization phases observed. For the Fe72Nb12B16 alloy, only the α-Mn-type metastable phase formed after annealing. The addition of 1 at.% Cu and 36 at.% Co led to the observation of the α-Mn-type and β-Mn-type metastable phases, respectively, and a reduction in the crystallization volume fraction in the metastable phase. The Fe36Co36Nb12B15Cu1 alloy only exhibited α-Fe(Co) phase as a primary phase, and the addition of both Cu and Co completely inhibited the precipitation of the metastable phase. Cu clusters were found in energy dispersive spectroscopy elemental maps. Compared with other alloys, Fe36Co36Nb12B15Cu1 alloy with both Cu and Co exhibited a lower coercivity (H
c) below 973 K.
Large spatial shifts of reflected light beam off biaxial hyperbolic materials
Authors: Shen 沈 Jia-Guo 加国 , Bakhtiar 哈 Syed-ul-hasnain 思内恩 , Song 宋 Hao-Yuan 浩元 , Zhou 周 Sheng 胜 , Fu 付 Shu-Fang 淑芳 , Wang 王 Xuan-Zhang 选章 , Wang 王 Xuan 暄 , Zhang 张 Qiang 强
Published: May 2023

Many optical systems that deal with polarization rely on the adaptability of controlling light reflection in the lithography-free nanostructure. In this study, we explore the Goos–Hänchen (GH) shift and Imbert–Fedorov (IF) shift in a biaxial hyperbolic film on a uniaxial hyperbolic substrate. This research statistically calculates and analyzes the GH shift and IF shift for the natural biaxial hyperbolic material (NBHM). We select the surface with the strongest anisotropy within the NBHM and obtain the complex beam-shift spectrum. By incorporating the NBHM film, the GH shift caused by a transversely magnetic incident-beam on the surface increases significantly compared with that on the uniaxial hyperbolic material. The maximum of GH shift can reach 86λ
0 at about 841 cm−1 when the thickness of NBHM is 90 nm, and the IF shift can approach 2.7λ
0 for a circularly-polarized beam incident on a 1700-nm-thick NBHM. It is found that the spatial-shift increases when a highly anisotropic hyperbolic polariton is excited in hyperbolic material, where the shift spectrum exhibits an oscillating behaviour accompanied with sharp shift peak (steep slope). This large spatial shift may provide an alternative strategy to develop novel sub-micrometric optical devices and biosensors.
Multiparametric non-linear TENS modulation to integrate intuitive sensory feedback
Authors: Bucciarelli Vittoria , Gozzi Noemi , Katic Natalija , Aiello Giovanna , Razzoli Margherita , Valle Giacomo , Raspopovic Stanisa
Published: May 2023

Objective. Transcutaneous electrical nerve stimulation (TENS) has been recently introduced in neurorehabilitation and neuroprosthetics as a promising, non-invasive sensory feedback restoration alternative to implantable neurostimulation. Yet, the adopted stimulation paradigms are typically based on single-parameter modulations (e.g. pulse amplitude (PA), pulse-width (PW) or pulse frequency (PF)). They elicit artificial sensations characterized by a low intensity resolution (e.g. few perceived levels), low naturalness and intuitiveness, hindering the acceptance of this technology. To address these issues, we designed novel multiparametric stimulation paradigms, featuring the simultaneous modulation of multiple parameters, and implemented them in real-time tests of performance when exploited as artificial sensory inputs. Approach. We initially investigated the contribution of PW and PF variations to the perceived sensation magnitude through discrimination tests. Then, we designed three multiparametric stimulation paradigms comparing them with a standard PW linear modulation in terms of evoked sensation naturalness and intensity. The most performant paradigms were then implemented in real-time in a Virtual Reality—TENS platform to assess their ability to provide intuitive somatosensory feedback in a functional task. Main results. Our study highlighted a strong negative correlation between perceived naturalness and intensity: less intense sensations are usually deemed as more similar to natural touch. In addition, we observed that PF and PW changes have a different weight on the perceived sensation intensity. As a result, we adapted the activation charge rate (ACR) equation, proposed for implantable neurostimulation to predict the perceived intensity while co-modulating the PF and charge per pulse, to TENS (ACRT). ACRT allowed to design different multiparametric TENS paradigms with the same absolute perceived intensity. Although not reported as more natural, the multiparametric paradigm, based on sinusoidal PF modulation, resulted being more intuitive and subconsciously integrated than the standard linear one. This allowed subjects to achieve a faster and more accurate functional performance. Significance. Our findings suggest that TENS-based, multiparametric neurostimulation, despite not consciously perceived naturally, can provide integrated and more intuitive somatosensory information, as functionally proved. This could be exploited to design novel encoding strategies able to improve the performance of non-invasive sensory feedback technologies.
Corrigendum: Model-based impurity emission front control using deuterium fueling and nitrogen seeding in TCV (2023 Nucl. Fusion 63 026006)
Authors: Koenders J.T.W. , Perek A. , Kool B. , Février O. , Ravensbergen T. , Galperti C. , Duval B.P. , Theiler C. , van Berkel M. , Team the TCV , MST1 Team the EUROfusion
Published: May 2023

In the published paper titled ‘Model-based impurity emission front control using deuterium fueling and nitrogen seeding in TCV’ (2023 Nucl. Fusion
63 026006), the legend of figure 5 shows the wrong colors: red and blue are switched. This corrigendum provides the correct legend for figure 5.
Particle pump-out induced by trapped electron mode turbulence in electron cyclotron heated plasmas on XuanLong-50 spherical torus
Authors: Wang Mingyuan , Li Jia , Bai Yukun , Dong Jiaqi , Shi Yuejiang , Zou Xiaolan , Liu Adi , Zhuang Ge , Li Hongyue , Li Songjian , Song Shaodong , Sun Tiantian , Liu Bing , Song Xianming , Liu Minsheng , Yuan Baoshan , Martin Peng Y.-K.
Published: May 2023

Particle pump-out effects induced by low-frequency (<200 kHz) density fluctuations were observed in solely electron cyclotron wave (ECW)-heated plasmas on the spherical torus XuanLong-50 (EXL-50) without a central solenoid. The intensity of the relative density fluctuations increases with increasing ECW power and decays when the ECW is turned off while sustaining the plasma current. The electron densities are maintained relatively high and steady when the density fluctuations are completely absent, indicating that the outward transport of electrons is dominated by the particle pump-out effect of the ECW. The density fluctuations are modulated by a supersonic molecular beam injection pulse and the modulation amplitude decreases with increasing electron density at the same ECW injection power and decreasing ECW power at the same electron density, respectively. Analysis revealed that a critical value of electron temperature gradient (ETG) triggers the density fluctuations, and the intensity of the relative density fluctuations is positively correlated with the ETG and approximately inversely proportional to the effective collision frequency. With plasma parameters similar to those of EXL-50 experiments, the HD7 code simulations demonstrate that trapped electron mode (TEM) turbulence can be excited by ETG higher than the critical value observed in the experiment. In addition, the dependence of the mode growth rate (supposed to be proportional to the saturation level of fluctuations in quasi-linear theory) and the measured intensity of the density fluctuations is comparable. The simulated outward particle flux integrated over the poloidal wave number spectrum is significant and proportional to ETG. These observations demonstrate that the density fluctuation is TEM turbulence, which is driven by ETG and induces particle pump-out when the electron density/effective electron collision frequency is low. The potential relevance of this work with the controls of plasma profiles, impurities, helium ash, and heat transport in future reactors of similar low effective collision frequency is also discussed.
The New Small Wheel electronics
Authors: Iakovidis G. , Levinson L. , Afik Y. , Alexa C. , Alexopoulos T. , Ameel J. , Amidei D. , Antrim D. , Badea A. , Bakalis C. , Boterenbrood H. , Brener R.S. , Chan S. , Chapman J. , Chatzianastasiou G. , Chen H. , Chu M.C. , Coliban R.M. , Costa de Paiva T. , de Geronimo G. , Edgar R. , Felt N. , Francescato S. , Franklin M. , Geralis T. , Gigliotti K. , Giromini P. , Gkountoumis P. , Grayzman I. , Guan L. , Guimaraes da Costa J. , Han L. , Hou S. , Hu X. , Hu K. , Huth J. , Ivanovici M. , Jin G. , Johns K. , Kajomovitz E. , Kehris G. , Kiskiras I. , Koulouris A. , Kyriakis E. , Lankford A. , Lee L. , Leung H. , Li F. , Liang Y. , Lu H. , Lupu N. , Martinez V. , Martoiu S. , Matakias D. , Mehalev I. , Mesolongitis I. , Miao P. , Mikenberg G. , Moleri L. , Moschovakos P. , Narevicius J. , Oliver J. , Pietreanu D. , Pinkham R. , Politis E. , Polychronakos V. , Popa S. , Prapa M.M. , Ravinovich I. , Roich A. , Rojas Caballero R.A. , Rozen Y. , Schernau M. , Schwartz T. , Scott G. , Shaked O. , Solis M. , Sun S. , Taffard A. , Tang S. , Tarem Z. , Tse W. , Tu Y. , Tuna A. , Tzanis P. , Tzanos S. , Vari R. , Vasile M. , Vdovin A. , Vermeulen J. , Wang J. , Wang X. , Wang A. , Wang R. , Xiao X. , Yao L. , Yildiz C. , Zachariadou K. , Zhou B. , Zhu J. , Zimmermann S.U. , Zormpa O.
Published: May 2023

The increase in luminosity, and consequent higher
backgrounds, of the LHC upgrades require improved rejection of fake
tracks in the forward region of the ATLAS Muon Spectrometer. The
New Small Wheel upgrade of the Muon Spectrometer aims to reduce the
large background of fake triggers from track segments that don't
originate from the interaction point. The New Small Wheel employs
two detector technologies, the resistive strip Micromegas detectors
and the “small” Thin Gap Chambers, with a total of 2.45 million
electrodes to be sensed. The two technologies require the design of
a complex electronics system given that it consists of two different
detector technologies and is required to provide both precision
readout and a fast trigger. It will operate in a high background
radiation region up to about 20 kHz/cm2 at the expected HL-LHC
luminosity of
ℒ = 7.5 × 1034 cm-2 s-1. The
architecture of the system is strongly defined by the GBTx data
aggregation ASIC, the newly-introduced FELIX data router and the
software based data handler of the ATLAS detector. The electronics
complex of this new detector was designed and developed in the last
ten years and consists of multiple radiation tolerant Application
Specific Integrated Circuits, multiple front-end boards, dense
boards with FPGA's and purpose-built Trigger Processor boards within
the ATCA standard. The New Small Wheel has been installed in 2021
and is undergoing integration within ATLAS for LHC Run 3. It should
operate through the end of Run 4 (December 2032). In this
manuscript, the overall design of the New Small Wheel electronics is
presented.
Hunting for bumps in the margins
Authors: Yallup David , Handley Will
Published: May 2023

Data driven modelling is vital to many analyses at collider
experiments, however the derived inference of physical properties
becomes subject to details of the model fitting procedure. This work
brings a principled Bayesian picture — based on the marginal
likelihood — of both data modelling and signal extraction to a
common collider physics scenario. First the marginal likelihood
based method is used to propose a more principled construction of
the background process, systematically exploring a variety of
candidate shapes. Second the picture is extended to propose the
marginal likelihood as a useful tool for anomaly detection
challenges in particle physics. This proposal offers insight into
both precise background model determination and demonstrates a
flexible method to extend signal determination beyond a simple bump
hunt.
A new approach to the study of spacelike submanifolds in a spherical Friedmann–Lemaître–Robertson–Walker spacetime: characterization of the stationary spacelike submanifolds as an application
Authors: Ferreira D , Lima E A , Palomo F J , Romero A
Published: May 2023

A natural codimension one isometric embedding of each

(
n
+
1
)

-dimensional spherical Friedmann–Lemaître–Robertson–Walker (FLRW) spacetime

I

×
f

S

n

in the

(
n
+
2
)

-dimensional Lorentz–Minkowski spacetime

L

n
+
2

permits to contemplate

I

×
f

S

n

as a rotation Lorentzian hypersurface in

L

n
+
2

. After a detailed study of such Lorentzian hypersurfaces, any k-dimensional spacelike submanifold of such an FLRW spacetime can be contemplated as a spacelike submanifold of

L

n
+
2

. Then, we use that situation to study k-dimensional stationary (i.e. of zero mean curvature vector field) spacelike submanifolds of the FLRW spacetime. In particular, we prove a wide extension of the Lorentzian version of the classical Takahashi theorem, giving a characterization of stationary spacelike submanifolds of

I

×
f

S

n

when contemplating them as spacelike submanifolds of

L

n
+
2

.
A QP perspective on topology change in Poisson–Lie T-duality
Authors: Arvanitakis Alex S , Blair Chris D A , Thompson Daniel C
Published: May 2023

We describe topological T-duality and Poisson–Lie T-duality in terms of QP (differential graded symplectic) manifolds and their canonical transformations. Duality is mediated by a QP-manifold on doubled non-abelian ‘correspondence’ space, from which we can perform mutually dual symplectic reductions, where certain canonical transformations play a vital role. In the presence of spectator coordinates, we show how the introduction of bibundle structure on correspondence space realises changes in the global fibration structure under Poisson–Lie duality. Our approach can be directly translated to the worldsheet to derive dual string current algebras. Finally, the canonical transformations appearing in our reduction procedure naturally suggest a Fourier–Mukai integral transformation for Poisson–Lie T-duality.
Electronic structure and topological phase transition in multi-orbital triangular lattice with rotation and mirror symmetry breaking
Authors: Hua Chenqiang , Gao Wenjin , Wu Meimei , Niu Tianchao , Zhou Miao
Published: May 2023

Triangular lattice is one of the most generic structures in the two-dimensional (2D) limit with numerous exotic properties, such as magnetic frustration and quantum spin liquid. Here, we investigate the electronic properties of a multi-orbital (p

x
, p

y
, p

z
) triangular lattice while focusing on the role of rotation and mirror symmetry breaking in regulating the topological phase diagram. The tight-binding modeling reveals that rotation symmetry (

C

2
z

) breaking splits the Dirac point and preserves the nodal loop. A further inclusion of broken horizontal mirror symmetry (

M

h

) destroys the nodal loop. Consequently, with spin–orbit coupling (SOC), the (p

x
, p

y
, p

z
)-orbital triangular lattice is topologically non-trivial with only

C

2
z

or

M

h

symmetry breaking. With both symmetries breaking, it becomes trivial, except when the SOC is large enough to initiate band inversion. For real materials, we propose that the recently grown AgSe/AgTe monolayer in a binary honeycomb structure is an ideal system to realize the multi-orbital triangular lattice. The first-principles calculations demonstrate that free-standing AgSe and AgTe are Z
2 non-trivial. On the Ag(111) substrate, AgSe becomes trivial because of the breaking of both

C

2
z

and

M

h

symmetries, whereas AgTe remains non-trivial because of the strong SOC of Te. Our work not only provides physical insights into the experimentally synthesized 2D binary honeycomb structures but also highlights the manipulation of electronic and topological properties through symmetry/orbital physics, which are valuable for designing new quantum materials and devices.
Male and female Brandt’s voles have higher reproductive success when they have more mating partners regardless of population density
Authors: Zhang Xin , Firman Renée C , Song Mingjing , Li Guoliang , Cheng Chaoyuan , Liu Jing , Huang Shuli , Batsuren Erdenetuya , Zhang Zhibin
Published: May 2023

Although population density and body mass are known to alter the mating strategies of individuals, their impacts on reproductive success have not been fully investigated. We examined genetic mating system variation (estimated number of mating partners), reproductive success (offspring number), and sperm competition intensity (sires per litter) in semi-natural populations of Brandt’s voles (Lasiopodomys brandtii) under low-, medium- and high-densities. We used 12 microsatellite genetic markers and parentage assignment of 3516 voles, with the aim of identifying the estimated number of mating partners and offspring produced by founder individuals. We provided strong evidence that individuals with more mating partners experienced increased reproductive success in all density groups, as measured by the production of more offspring, compared with individuals that had fewer mating partners. Further, we found that large males had more mating partners (especially in high-population density enclosures) and also produced more offspring relative to smaller males. In high-density (HD) enclosures, the average reproductive success per female vole was lower (a negative density-dependent effect), but voles had more mating partners, more sires per litter, but lower paternity skew compared to low-density enclosures. Our results suggests that Brandt’s voles increased reproductive success through increasing mating partners under HD stress which may have significant implications in offsetting the negative density-dependency effect on population growth.
McAN: a novel computational algorithm and platform for constructing and visualizing haplotype networks
Authors: Li Lun , Xu Bo , Tian Dongmei , Wang Anke , Zhu Junwei , Li Cuiping , Li Na , Zhao Wei , Shi Leisheng , Xue Yongbiao , Zhang Zhang , Bao Yiming , Zhao Wenming , Song Shuhui
Published: May 2023

Haplotype networks are graphs used to represent evolutionary relationships between a set of taxa and are characterized by intuitiveness in analyzing genealogical relationships of closely related genomes. We here propose a novel algorithm termed McAN that considers mutation spectrum history (mutations in ancestry haplotype should be contained in descendant haplotype), node size (corresponding to sample count for a given node) and sampling time when constructing haplotype network. We show that McAN is two orders of magnitude faster than state-of-the-art algorithms without losing accuracy, making it suitable for analysis of a large number of sequences. Based on our algorithm, we developed an online web server and offline tool for haplotype network construction, community lineage determination, and interactive network visualization. We demonstrate that McAN is highly suitable for analyzing and visualizing massive genomic data and is helpful to enhance the understanding of genome evolution. Availability: Source code is written in C/C++ and available at https://github.com/Theory-Lun/McAN and https://ngdc.cncb.ac.cn/biocode/tools/BT007301 under the MIT license. Web server is available at https://ngdc.cncb.ac.cn/bit/hapnet/. SARS-CoV-2 dataset are available at https://ngdc.cncb.ac.cn/ncov/. Contact: songshh@big.ac.cn (Song S), zhaowm@big.ac.cn (Zhao W), baoym@big.ac.cn (Bao Y), zhangzhang@big.ac.cn (Zhang Z), ybxue@big.ac.cn (Xue Y).
Broad phylogenetic analyses of the leech family Glossiphoniidae (Annelida: Clitellata) reveals two independent origins of kangaroo leeches
Authors: Torres-Carrera Gerardo , Muñiz-Pareja Flavia C , Maza-Acuña Albert N , Oceguera-Figueroa Alejandro
Published: May 2023

Parental care is uncommon within Annelida. However, a remarkable exception is in the leech family Glossiphoniidae in which all its members keep their offspring attached to the ventral surface for varying lengths of time. Considered as the culmination in the evolution of parental care in leeches, two glossiphoniids, Marsupiobdella africana from South Africa and Maiabdella batracophila from South America, have a brood pouch or marsupium in which their offspring are protected. Interestingly, the structure is located in exactly the same region of the body in both species. Based on phylogenetic analysis of Glossiphoniidae, including use of nuclear and mitochondrial DNA sequences, we investigated for the first time the phylogenetic position of the two kangaroo leeches. Our results indicate that marsupium-bearing leeches belong to separate lineages, with each species more closely related to other leeches from their respective continent. We infer that the marsupium evolved independently from ancestors that maintained their eggs inside thin-walled, flexible, transparent cocoons attached directly to the ventral surface of the parents. Together with the evolution of a marsupium, both species have also ceased to produce cocoons, which are normally a characteristic of Glossiphoniidae.
Creatine metabolism at the uterine–placental interface throughout gestation in sheep
Authors: Sah Nirvay , Stenhouse Claire , Halloran Katherine M , Moses Robyn M , Seo Heewon , Burghardt Robert C , Johnson Gregory A , Wu Guoyao , Bazer Fuller W
Published: May 2023

The placenta requires high levels of adenosine triphosphate to maintain a metabolically active state throughout gestation. The creatine–creatine kinase–phosphocreatine system is known to buffer adenosine triphosphate levels; however, the role(s) creatine–creatine kinase–phosphocreatine system plays in uterine and placental metabolism throughout gestation is poorly understood. In this study, Suffolk ewes were ovariohysterectomized on Days 30, 50, 70, 90, 110 and 125 of gestation (n = 3–5 ewes/per day, except n = 2 on Day 50) and uterine and placental tissues subjected to analyses to measure metabolites, mRNAs, and proteins related to the creatine–creatine kinase–phosphocreatine system. Day of gestation affected concentrations and total amounts of guanidinoacetate and creatine in maternal plasma, amniotic fluid and allantoic fluid (P < 0.05). Expression of mRNAs for arginine:glycine amidinotransferase, guanidinoacetate methyltransferase, creatine kinase B, and solute carrier 16A12 in endometria and for arginine:glycine amidinotransferase and creatine kinase B in placentomes changed significantly across days of gestation (P < 0.05). The arginine:glycine amidinotransferase protein was more abundant in uterine luminal epithelium on Days 90 and 125 compared to Days 30 and 50 (P < 0.01). The chorionic epithelium of placentomes expressed guanidinoacetate methyltransferase and solute carrier 6A13 throughout gestation. Creatine transporter (solute carrier 6A8) was expressed by the uterine luminal epithelium and trophectoderm of placentomes throughout gestation. Creatine kinase (creatine kinase B and CKMT1) proteins were localized primarily to the uterine luminal epithelium and to the placental chorionic epithelium of placentomes throughout gestation. Collectively, these results demonstrate cell-specific and temporal regulation of components of the creatine–creatine kinase–phosphocreatine system that likely influence energy homeostasis for fetal–placental development.
A 21-year-old woman with progressive asymptomatic skin laxity in flexural regions
Authors: Gambichler Thilo , Hoffjan Sabine , Nagel Mato , Terschlüsen Meike , Mansour Rita , Würfel Lina , Hoffmann Klaus , Susok Laura , Dickel Heinrich , Doerler Martin
Published: May 2023

We describe a 21-year-old woman with progressive asymptomatic skin laxity in the flexural regions.
Low-grade cutaneous immune-related adverse events leading to immunotherapy discontinuation
Authors: Jacoby Ted V , Asdourian Maria S , Shah Nishi  , Otto Tracey S , Thompson Leah L , Reynolds Kerry L , Chen Steven T
Published: May 2023

Cutaneous immune-related adverse events (cirAEs) are a common toxicity arising from the use of immune checkpoint inhibitors (ICIs) to treat cancer. We provide a case series of 10 patients who presented with low-severity cirAEs and who had their ICI discontinued against published guidelines, and we highlight areas for intervention to decrease the risk of this occurrence.
Face recognition ability can be predicted by microstructural properties of white matter: a study of diffusion tensor imaging (DTI)
Authors: Zhou Guifei , Xiao Naiqi G , Sun Yuhao , Li Hong , Liu Jiangang
Published: May 2023

There is a great individual difference in people’s face recognition ability (FRA). This study aimed to reveal the neural mechanism underlying such individual differences. Elastic-net regression models were constructed to predict FRA based on the white matter (WM) microstructural properties. We found that FRA can be accurately predicted by the WM microstructural properties. For the right inferior longitudinal fasciculus (ILF) and bilateral arcuate fasciculus (AF), FRA was correlated negatively to fractional anisotropy (FA), but positively to radial diffusivity (RD). In contrast, for the corpus callosum forceps minor (CFM), FRA was correlated positively to FA, but negatively to RD. Such various patterns of the WM microstructural properties suggested a positive correlation between FRA and fiber diameter for the right ILF and bilateral AF, but a negative correlation between FRA and diameter of the CFM. These findings reflected that FRA was correlated positively to connectivities of the right ILF and bilateral AF, but negatively to those of the CFM. These findings not only confirmed the significant role of the right ILF in face recognition, but also revealed the involvement of the bilateral AF and CFM in face recognition, particularly implying the important role of hemisphere lateralization modulated by transcallosal connectivity in face recognition.
Enhanced intersubject similarity in functional connectivity by long-term abacus training
Authors: Zhang Yi , Xu Tianyong , Han Xiao , Wang Yanjie , Liu Huafeng , Zhou Changsong , Chen Feiyan
Published: May 2023

The individual difference of intrinsic functional connectivity is increasingly acknowledged to be biologically informative and behaviorally relevant. However, such valuable information is still discounted as a stochastic variation in previous studies of cognitive training. Here, we explored the plasticity of intersubject similarity in functional connectivity (ISFC), induced by long-term abacus-based mental calculation (AMC) training. Using a longitudinal dataset (AMC: n = 40, 5-year training; Control: n = 43), we found robust training effect of enhanced ISFC, after accounting for the factor of development. Notably, the enhancement focused on selective subsets of FCs, or the “critical FCs,” which predominantly impacted the default-mode and visual networks. Using a cross-sectional dataset with a larger sample (AMC: n = 93, 1/3/5-year training; Control: n = 110), we observed that the “critical FCs” and its intersubject similarity could predict mental calculation ability and its intersubject similarity, respectively, in the AMC group. However, such predictions cannot be generalized to the control group, suggesting that long-term training may be a prerequisite for establishing such brain–behavior relationships. Jointly, our findings implicated that the enhanced ISFC with profound impact on the default-mode network could be a plastic change that is associated with behavioral gains of training.
Update on persistent acute kidney injury in critical illnesses
Authors: Samoni Sara , De Rosa Silvia , Ronco Claudio , Castellano Giuseppe
Published: May 2023

Acute kidney injury (AKI) affects about half of patients admitted to the intensive care unit (ICU), and worsens their short- and long-term outcomes. Apparently self-limiting AKI episodes initiate a progression toward chronic kidney disease (CKD) through cellular and molecular mechanisms that are yet to be explained. In particular, persistent AKI, defined in 2016 by the Acute Dialysis Quality Initiative as an AKI which lasts more than 48 h from its onset, has been correlated with higher morbidity and mortality, and with a higher progression to acute kidney disease (AKD) and CKD than transient AKI (i.e. AKI with a reversal within 48 h). This classification has been also used in the setting of solid organ transplantation, demonstrating similar outcomes. Due to its incidence and poor prognosis and because prompt interventions seem to change its course, persistent AKI should be recognized early and followed-up also after its recovery. However, while AKI and CKD are well-described syndromes, persistent AKI and AKD are relatively new entities. The purpose of this review is to highlight the key phases of persistent AKI in ICU patients in terms of both clinical and mechanistic features in order to offer to clinicians and researchers an updated basis from which to start improving patients’ care and direct future research.