bluuebunny/crossref_metadata_2025 huggingface dataset:
Single-crystalline LiNbO3 film based wideband SAW devices with spurious-free responses for future RF front-ends
Authors: He Xingli , Chen Kai , Kong Linghui , Li Peng
Published: March 2022

This work demonstrates super-high frequency wave-guided surface acoustic wave (SAW) devices based on LiNbO3/SiO2/Si layered substrates. SAW resonators with fundamental operating frequency to the 7-GHz range were developed, and wave modes like the Rayleigh, Shear-horizontal (SH), Pseudo-Bulk, etc., were observed. Furthermore, effective coupling coefficients (k2eff) and quality factor (Q) of the devices have been investigated systematically. Specifically, spurious-free SAW resonators with the SH wave frequency over 7.40 GHz and the high k2eff value of ∼7.8% were obtained at a nanoscale wavelength of 480 nm. Finally, high-performance filters with a bandwidth over 300 MHz were achieved. The demonstrated filters show sharp roll-off and spurious-free responses within the passband with insertion loss <−5 dB and a small temperature coefficient of frequency of ∼−45.8 ppm/K at a super-high frequency of 7.17 GHz. Upon further optimizations, high-performance SAW devices built on a single crystalline LiNbO3 film can potentially enable the low-loss and wideband signal processing functions, promising for the next-generation radio frequency front-end system applications.
Binocular mirror–symmetric microsaccadic sampling enables
Drosophila
hyperacute 3D vision
Authors: Kemppainen Joni , Scales Ben , Razban Haghighi Keivan , Takalo Jouni , Mansour Neveen , McManus James , Leko Gabor , Saari Paulus , Hurcomb James , Antohi Andra , Suuronen Jussi-Petteri , Blanchard Florence , Hardie Roger C. , Song Zhuoyi , Hampton Mark , Eckermann Marina , Westermeier Fabian , Frohn Jasper , Hoekstra Hugo , Lee Chi-Hon , Huttula Marko , Mokso Rajmund , Juusola Mikko
Published: March 2022

Significance

To move efficiently, animals must continuously work out their x,y,z positions with respect to real-world objects, and many animals have a pair of eyes to achieve this. How photoreceptors actively sample the eyes’ optical image disparity is not understood because this fundamental information-limiting step has not been investigated in vivo over the eyes’ whole sampling matrix. This integrative multiscale study will advance our current understanding of stereopsis from static image disparity comparison to a morphodynamic active sampling theory. It shows how photomechanical photoreceptor microsaccades enable
Drosophila
superresolution three-dimensional vision and proposes neural computations for accurately predicting these flies’ depth-perception dynamics, limits, and visual behaviors.
Metal–organic cycle-based multistage assemblies
Authors: Sun Yan , Tuo Wei , Stang Peter J.
Published: March 2022

Significance

Different from polymers or peptides (lacking metals), metal–organic cycles (MOCs) have properties which arise from the combination of metals and common nonmetal elements and topologies. The development of MOC supramolecular materials is in its infancy, and how the coordination bonds work to make the corresponding suprastructures is unknown. This has limited the potential application of these MOC-based materials. Considering the applications of individual MOCs, the study and discovery of the unique factors in MOC-involved multilevel self-assembly are critical to further our knowledge of the underlying molecular mechanisms of metal-containing compounds. Here, a systematic study of MOC assembly in various solvent systems has confirmed the critical role of coordination linkers in tuning the shape and size of the MOC-derived suprastructures.
Hatching is modulated by microRNA-378a-3p derived from extracellular vesicles secreted by blastocysts
Authors: Pavani Krishna Chaitanya , Meese Tim , Pascottini Osvaldo Bogado , Guan XueFeng , Lin Xiaoyuan , Peelman Luc , Hamacher Joachim , Van Nieuwerburgh Filip , Deforce Dieter , Boel Annekatrien , Heindryckx Björn , Tilleman Kelly , Van Soom Ann , Gadella Bart M. , Hendrix An , Smits Katrien
Published: March 2022

Significance

Hatching from the zona pellucida is a prerequisite for embryo implantation and is less likely to occur in vitro for reasons unknown. Extracellular vesicles (EVs) are secreted by the embryo into the culture medium. Yet the role that embryonic EVs and their cargo microRNAs (miRNAs) play in blastocyst hatching has not been elucidated, partially due to the difficulties of isolating them from low amounts of culture medium. Here, we optimized EV-miRNA isolation from medium conditioned by individually cultured bovine embryos and subsequently showed that miR-378a-3p, which was up-regulated in EVs secreted by blastocysts, plays a crucial role in promoting blastocyst hatching. This demonstrates the regulatory effect of miR-378-3p on hatching, which is an established embryo quality parameter linked with implantation.
Synaptic pruning of murine adult-born neurons by microglia depends on phosphatidylserine
Authors: Kurematsu Chihiro , Sawada Masato , Ohmuraya Masaki , Tanaka Motoki , Kuboyama Kazuya , Ogino Takashi , Matsumoto Mami , Oishi Hisashi , Inada Hiroyuki , Ishido Yuri , Sakakibara Yukina , Nguyen Huy Bang , Thai Truc Quynh , Kohsaka Shinichi , Ohno Nobuhiko , Yamada Maki K. , Asai Masato , Sokabe Masahiro , Nabekura Junichi , Asano Kenichi , Tanaka Masato , Sawamoto Kazunobu
Published: March 2022

New neurons, continuously added in the adult olfactory bulb (OB) and hippocampus, are involved in information processing in neural circuits. Here, we show that synaptic pruning of adult-born neurons by microglia depends on phosphatidylserine (PS), whose exposure on dendritic spines is inversely correlated with their input activity. To study the role of PS in spine pruning by microglia in vivo, we developed an inducible transgenic mouse line, in which the exposed PS is masked by a dominant-negative form of milk fat globule-EGF-factor 8 (MFG-E8), MFG-E8D89E. In this transgenic mouse, the spine pruning of adult-born neurons by microglia is impaired in the OB and hippocampus. Furthermore, the electrophysiological properties of these adult-born neurons are altered in MFG-E8D89E mice. These data suggest that PS is involved in the microglial spine pruning and the functional maturation of adult-born neurons. The MFG-E8D89E–based genetic approach shown in this study has broad applications for understanding the biology of PS-mediated phagocytosis in vivo.
Neutralizing antibodies protect mice against Venezuelan equine encephalitis virus aerosol challenge
Authors: Kafai Natasha M. , Williamson Lauren E. , Binshtein Elad , Sukupolvi-Petty Soila , Gardner Christina L. , Liu Jaclyn , Mackin Samantha , Kim Arthur S. , Kose Nurgun , Carnahan Robert H. , Jung Ana , Droit Lindsay , Reed Douglas S. , Handley Scott A. , Klimstra William B. , Crowe James E. , Diamond Michael S.
Published: March 2022

Venezuelan equine encephalitis virus (VEEV) remains a risk for epidemic emergence or use as an aerosolized bioweapon. To develop possible countermeasures, we isolated VEEV-specific neutralizing monoclonal antibodies (mAbs) from mice and a human immunized with attenuated VEEV strains. Functional assays and epitope mapping established that potently inhibitory anti-VEEV mAbs bind distinct antigenic sites in the A or B domains of the E2 glycoprotein and block multiple steps in the viral replication cycle including attachment, fusion, and egress. A 3.2-Å cryo-electron microscopy reconstruction of VEEV virus-like particles bound by a human Fab suggests that antibody engagement of the B domain may result in cross-linking of neighboring spikes to prevent conformational requirements for viral fusion. Prophylaxis or postexposure therapy with these mAbs protected mice against lethal aerosol challenge with VEEV. Our study defines functional and structural mechanisms of mAb protection and suggests that multiple antigenic determinants on VEEV can be targeted for vaccine or antibody-based therapeutic development.
Spliced isoforms of the cardiac Nav1.5 channel modify channel activation by distinct structural mechanisms
Authors: Mancino Adamo S. , Glass William G. , Yan Yuhao , Biggin Philip C. , Bowie Derek
Published: March 2022

Alternative splicing is an important cellular mechanism that fine tunes the gating properties of both voltage- and ligand-gated ion-channels. The cardiac voltage-gated sodium channel, Nav1.5, is subject to alternative splicing of the DI S3–S4 linker, which generates two types of channels with different activation properties. Here, we show that the gating differences between the adult (mH1) and neonatal (Nav1.5e) isoforms of Nav1.5 are mediated by two amino acid residues: Thr/Ser at position 207 and Asp/Lys at position 211. Electrophysiological experiments, in conjunction with molecular dynamics simulations, revealed that each residue contributes equally to the overall gating shifts in activation, but that the underlying structural mechanisms are different. Asp/Lys at position 211 acts through electrostatic interactions, whereas Thr/Ser at position 207 is predicted to alter the hydrogen bond network at the top of the S3 helix. These distinct structural mechanisms work together to modify movement of the voltage-sensitive S4 helix to bring about channel activation. Interestingly, mutation of the homologous Asp and Thr residues of the skeletal muscle isoform, Nav1.4, to Lys and Ser, respectively, confers a similar gating shift in channel activation, suggesting that these residues may fulfill a conserved role across other Nav channel family members.
Bottom-up reconstruction of viable GW170817 compatible Einstein–Gauss–Bonnet theories
Authors: Oikonomou V K , Katzanis P D , Papadimitriou Ilias C
Published: March 2022

In this work we shall use a bottom-up approach for obtaining viable inflationary Einstein–Gauss–Bonnet models which are also compatible with the GW170817 event. Specifically, we shall use a recently developed theoretical framework in which we shall specify only the tensor-to-scalar ratio, in terms of the e-foldings number. Starting from the tensor-to-scalar ratio, we shall reconstruct from it the Einstein–Gauss–Bonnet theory which can yield such a tensor-to-scalar ratio, finding the scalar potential and the Gauss–Bonnet coupling scalar function as functions of the e-foldings number. Accordingly, the calculation of the spectral index of the primordial scalar perturbations, and of the tensor spectral index easily is greatly simplified and these observational indices can easily be found. After presenting the general formalism for the bottom-up reconstruction, we exemplify our findings by presenting several Einstein–Gauss–Bonnet models of interest which yield a viable inflationary phenomenology. These models have also an interesting common characteristic, which is a blue tilted tensor spectral index. We also investigate the predicted energy spectrum of the primordial gravitational waves for these Einstein–Gauss–Bonnet models, and as we show, all the models yield a detectable primordial wave energy power spectrum.
Multi-parameter analysis of the obstacle scattering problem
Authors: Dalla Riva Matteo , Luzzini Paolo , Musolino Paolo
Published: March 2022

We consider the acoustic field scattered by a bounded impenetrable obstacle and we study its dependence upon a certain set of parameters. As usual, the problem is modeled by an exterior Dirichlet problem for the Helmholtz equation Δu + k
2
u = 0. We show that the solution u and its far field pattern u
∞ depend real analytically on the shape of the obstacle, the wave number k, and the Dirichlet datum. We also prove a similar result for the corresponding Dirichlet-to-Neumann map.
Probing nanometal surface energy transfer between nanocopper and MoS2 for glutathione sensing
Authors: K Janani Archana , Balasubramanian Karthikeyan
Published: March 2022

Cu nanoparticles and 2D-MoS2 nanosheets have been synthesised and the morphology of the prepared samples has been characterised using high-resolution transmission electron microscopy and field emission scanning electron microscopy. Steady-state fluorescence studies exhibit quenching of fluorescence intensity upon the addition of quencher in varying amounts. Time-resolved fluorescence studies show a reduction of fluorescence lifetime in the presence of quencher. A thorough investigation of energy transfer between MoS2 and copper nanoparticles has been accomplished using steady-state and time-resolved fluorescence studies. The results are more consistent with the nanometal surface energy transfer (NSET) theory, which follows a 1/d
4 distance dependence than the Förster resonance energy transfer theory exhibiting 1/d
6 distance dependence. For the MoS2–Cu pair, the NSET efficiency, the proximal distance between donor–acceptor pairs and the rate of energy transfer has been explored. Energy transfer-based fluorescent biosensors have been regarded as potential candidates in biosensing applications. Glutathione, an endogenous tripeptide compound, plays a vital role as an antioxidant in the human body. Irregular glutathione levels have been linked to several adverse illnesses. Henceforth, detection of glutathione levels is indispensable. The Cu–MoS2 pair was used for glutathione sensing in nanomolar concentration (nM), which demonstrated a turn-off sensing behaviour.
1D fluid model of the interaction between helium APPJ and deionized water
Authors: Liu Yifan , Liu Dingxin , Luo Santu , Sun Bowen , Zhang Mingyan , Yang Aijun , Kong Michael G
Published: March 2022

Atmospheric pressure plasma jets (APPJs) are widely used for the treatment of water-containing substances such as human tissue, leading to a necessity of understanding the interaction between APPJs and water solutions for the development of plasma biomedicine. The reported two- or three-dimensional fluid models are shown to be an effective method for this study. However, owing to the complex chemistry in APPJ-water interaction, little of them could provide a quantitative estimation of reactive species, which are difficult to be measured but of much interest in the applications. In this paper, a one-dimensional fluid model is developed to simulate the interaction between a helium APPJ and deionized water, which incorporates a relatively comprehensive chemistry both in gas and liquid phases but with a moderate computational load. The composition and distribution of reactive species are quantified during a plasma treatment time of 6 min, which is typical in practice. By considering the sidewise loss inside the quartz tube, the air mixing outside the quartz tube, the conductivity of deionized water, and the chlorine evolution reaction, the simulation results agree well with the experiments. It is found that the plasma could be divided into three regions with much different physicochemical properties, mainly due to the sidewise loss, the air mixing and the water evaporation. In plasma-activated water, H2O2aq and HNO2aq/NO2aq
− are the dominant reactive species, and OHaq is the key intermediate species for the transformation among other reactive species. Finally, the chemical pathways for the production of aqueous reactive species are elucidated.
Non-contact measurement of human respiration using an infrared thermal camera and the deep learning method
Authors: Shu Shuangbao , Liang Huajun , Zhang Yu , Zhang Yuzhong , Yang Ziqiang
Published: March 2022

The existing methods of contact respiration rate (RR) measurement can bring discomfort to the person being measured. However, RR is a human index that has to be monitored in clinical medicine. To overcome the limitations of contact measurement methods, a non-contact RR measurement method based on an infrared thermal camera is proposed. This is based on the phenomenon that human breathing causes periodic temperature changes around the nostrils. First, an infrared thermal camera is used to collect image sequences of the human face. And then, to track a region-of-interest (ROI) in moving image sequences, the You Only Look Once V3 deep learning method is used to track the nostril ROI from the recorded facial image sequences. The performance of the deep learning model is analyzed through experiments. The average temperature of the nostril ROI of the tracked image is calculated, and the temperature change value of the continuous image series can be obtained. The temperature change curve reflects the respiratory process. A Butterworth low-pass filter is used to filter the continuous temperature value to obtain robust respiratory signals, to improve the signal-noise ratio. Last, the respiratory rate is calculated by time-domain and frequency-domain methods. RR is calculated in different conditions, such as normal respiration, fast respiration, and slow respiration. Through the training, the training accuracy of the model reaches 97.9%. Experimental results show that the method can achieve high precision, and the maximum error is not more than 2%. Those indicate the proposed method can effectively measure the RR. Therefore, the proposed non-contact RR measurement method can be a useful reference for clinical RR measurement and other applications.
Evaluating the applicability of classical and neural network interatomic potentials for modeling body centered cubic polymorph of magnesium
Authors: F Troncoso Javier , Turlo Vladyslav
Published: March 2022

Magnesium (Mg) is one of the most abundant metallic elements in nature and presents attractive mechanical properties in the industry. Particularly, it has a low density and relatively high strength/weight and stiffness/weight ratios, which make it one of the most attractive lightweight metals. However, the huge potential of Mg is restricted by its low ductility, associated with its hexagonal close packed (hcp) structure. This problem can be solved if Mg adopts the body centered cubic (bcc) structure, which is stable at high pressure or in confinement with stiff bcc metals like Nb. Molecular dynamics method is a magnificent tool to study material’s structure and deformation mechanisms at the atomic level, however, requiring accurate interatomic potentials. The majority of the interatomic potentials available in the literature for Mg have only been fitted to the properties of its stable hcp phase. In the present work, we perform systematic study of applicability of currently available Mg potentials to modeling the properties of metastable bcc polymorph of Mg, taking into account cohesive energy curves, elastic constants, stacking fault energies, and phonon dispersion curves. We conclude that the modified embedded atom method (MEAM) potentials are the most suitable for investigating bcc Mg in Mg/Nb nano-composites, while the properties of high-pressure bcc Mg would be better modeled by neural network interatomic potentials after different local atomic environments corresponding to bcc Mg being included into the fitting database.
Cascaded mutual enhancing networks for brain tumor subregion segmentation in multiparametric MRI
Authors: Momin Shadab , Lei Yang , Tian Zhen , Roper Justin , Lin Jolinta , Kahn Shannon , Shu Hui-Kuo , Bradley Jeffrey , Liu Tian , Yang Xiaofeng
Published: March 2022

Accurate segmentation of glioma and its subregions plays an important role in radiotherapy treatment planning. Due to a very populated multiparameter magnetic resonance imaging image, manual segmentation tasks can be very time-consuming, meticulous, and prone to subjective errors. Here, we propose a novel deep learning framework based on mutual enhancing networks to automatically segment brain tumor subregions. The proposed framework is suitable for the segmentation of brain tumor subregions owing to the contribution of Retina U-Net followed by the implementation of a mutual enhancing strategy between the classification localization map (CLM) module and segmentation module. Retina U-Net is trained to accurately identify view-of-interest and feature maps of the whole tumor (WT), which are then transferred to the CLM module and segmentation module. Subsequently, CLM generated by the CLM module is integrated with the segmentation module to bring forth a mutual enhancing strategy. In this way, our proposed framework first focuses on WT through Retina U-Net, and since WT consists of subregions, a mutual enhancing strategy then further aims to classify and segment subregions embedded within WT. We implemented and evaluated our proposed framework on the BraTS 2020 dataset consisting of 369 cases. We performed a 5-fold cross-validation on 200 datasets and a hold-out test on the remaining 169 cases. To demonstrate the effectiveness of our network design, we compared our method against the networks without Retina U-Net, mutual enhancing strategy, and a recently published Cascaded U-Net architecture. Results of all four methods were compared to the ground truth for segmentation and localization accuracies. Our method yielded significantly (P < 0.01) better values of dice-similarity-coefficient, center-of-mass-distance, and volume difference compared to all three competing methods across all tumor labels (necrosis and non-enhancing, edema, enhancing tumor, WT, tumor core) on both validation and hold-out dataset. Overall quantitative and statistical results of this work demonstrate the ability of our method to both accurately and automatically segment brain tumor subregions.
Interbeat interval-based sleep staging: work in progress toward real-time implementation
Authors: Garcia-Molina Gary , Jiang Jiewei
Published: March 2022

Objective. Cardiac activity changes during sleep enable real-time sleep staging. We developed a deep neural network (DNN) to detect sleep stages using interbeat intervals (IBIs) extracted from electrocardiogram signals. Approach. Data from healthy and apnea subjects were used for training and validation; 2 additional datasets (healthy and sleep disorders subjects) were used for testing. R-peak detection was used to determine IBIs before resampling at 2 Hz; the resulting signal was segmented into 150 s windows (30 s shift). DNN output approximated the probabilities of a window belonging to light, deep, REM, or wake stages. Cohen’s Kappa, accuracy, and sensitivity/specificity per stage were determined, and Kappa was optimized using thresholds on probability ratios for each stage versus light sleep. Main results. Mean (SD) Kappa and accuracy for 4 sleep stages were 0.44 (0.09) and 0.65 (0.07), respectively, in healthy subjects. For 3 sleep stages (light+deep, REM, and wake), Kappa and accuracy were 0.52 (0.12) and 0.76 (0.07), respectively. Algorithm performance on data from subjects with REM behavior disorder or periodic limb movement disorder was significantly worse, with Kappa of 0.24 (0.09) and 0.36 (0.12), respectively. Average processing time by an ARM microprocessor for a 300-sample window was 19.2 ms. Significance. IBIs can be obtained from a variety of cardiac signals, including electrocardiogram, photoplethysmography, and ballistocardiography. The DNN algorithm presented is 3 orders of magnitude smaller compared with state-of-the-art algorithms and was developed to perform real-time, IBI-based sleep staging. With high specificity and moderate sensitivity for deep and REM sleep, small footprint, and causal processing, this algorithm may be used across different platforms to perform real-time sleep staging and direct intervention strategies. Novelty & Significance (92/100 words) This article describes the development and testing of a deep neural network-based algorithm to detect sleep stages using interbeat intervals, which can be obtained from a variety of cardiac signals including photoplethysmography, electrocardiogram, and ballistocardiography. Based on the interbeat intervals identified in electrocardiogram signals, the algorithm architecture included a group of convolution layers and a group of long short-term memory layers. With its small footprint, fast processing time, high specificity and good sensitivity for deep and REM sleep, this algorithm may provide a good option for real-time sleep staging to direct interventions.
Electropositive core in electronegative magnetized capacitive radio frequency plasmas
Authors: Wang Li , Vass Máté , Donkó Zoltán , Hartmann Peter , Derzsi Aranka , Song Yuan-Hong , Schulze Julian
Published: March 2022

The magnetized drift-ambipolar (‘m-DA’) electron power absorption mode and a sequence of structural transitions, including the formation of an electropositive core where the electron density is much higher than the negative ion density, are identified in a magnetized capacitive Radio-Frequency (RF) plasma of a strongly electronegative gas, CF4. The m-DA mode is caused by a magnetic enhancement of the bulk electric field due to the attenuation of the electron transport and plasma conductivity across the magnetic field. This leads to the formation of ionization maxima at distinct axial positions and a local trapping of electrons by the magnetic field as a function of its strength.
Influence of voltage and gap distance on the dynamics of the ionization front, plasma dots, produced by nanosecond pulsed discharges at water surface
Authors: Herrmann Antoine , Margot Joëlle , Hamdan Ahmad
Published: March 2022

A streamer discharge is a highly reactive and dynamic non-thermal plasma. It has been used in many applications, including environmental remediation, medicine, and material processing. Although the physics of streamer discharges in gaseous media is well understood, its interaction with a solid and liquid dielectric surfaces remains under investigation, in particular when quantitative data are searched for. In this study, we investigate the influence of voltage amplitude (V
a) and interelectrode air gap distance (d) on the pulsed discharge behavior at the surface of distilled water. Time resolved images show the formation and propagation of plasma dots (ionization front of streamers) at water surface. Because of its stochastical nature, a large number of discharge was performed to address the influence of V
a and d on the number of plasma dots (N
Dots) as well on the charge per dot (Q
Dot). As expected, for a given V
a, the breakdown voltage is found to increase with d. Moreover, N
Dots decreases linearly with d at the rate of ∼1 dot by 200 μm of increase, while the total injected charge decays linearly with a rate of ∼8–9 nC by 200 μm of increase. Based on the measurement of the propagation velocity of the plasma dots and on the estimation of the electric field in the medium, an average mobility of plasma dots of ∼1.5 cm2 Vs−1 is evaluated. From both this value and the instantaneous measured propagation velocity, the temporal evolution of Q
Dot and charge number are determined. The observations reported here are of interest for fundamental studies as well as for applications where well-controlled charge transfer to surfaces is crucial.
Survey, taxonomy, and methods of QCA-based design techniques—part I: digital circuits
Authors: Fazili Mohammad Mudakir , Shah Mohsin Fayaz , Naz Syed Farah , Shah Ambika Prasad
Published: March 2022

Quantum-dot cellular automata (QCA) are a promising, novel nanoscale technology that allow the design of integrated circuits with high speed, low power consumption, and high density. Because of this potential benefit, QCA are chosen as a viable alternative to complementary metal-oxide semiconductor (CMOS) technology. In this paper, we have provided a comprehensive review of various types of digital circuits and modules in QCA nanotechnology. We have discussed circuits such as XOR/XNOR, half and full adder, multiplexers and demultiplexers, comparators, flip-flops, arithmetic and logical unit, and random-access memory. We have shown how these circuits are designed using various methodologies such as different types of cross-overs, multi-layer designs, or using cell-to-cell interaction method with their corresponding advantages and overheads. These logical circuits are compared on the basis of various parameters including cell area, total area, latency, number of cells, energy dissipation, and complexity and are explained starting from the design which is having larger cell count to the current efficient design present in terms of the above parameters.
Survey, taxonomy, and methods of QCA-based design techniques—part II: reliability and security
Authors: Fazili Mohammad Mudakir , Shah Mohsin Fayaz , Naz Syed Farah , Shah Ambika Prasad
Published: March 2022

Quantum-dot cellular automata (QCA) is a new and adroit technology currently under extensive research for post-complementary metal-oxide-semiconductor era VLSI chip design. QCA has promised more reliable, fault-tolerant and secure chip designs. In addition, while analyzing QCA circuits for power and energy dissipation, promising results have been reported that suggest that QCA circuits dissipate significantly less energy and operate very close to the Shannon–von Neumann–Landauer limit. Security is another concern that has led to the development of QCA-based security systems such as physically unclonable functions and true random number generators. In this paper, a survey of different fault-tolerant and QCA-based security circuits is provided, along with a discussion of critical design aspects and parameters of QCA technology.
Smart self-sensory TRC pipes—proof of concept
Authors: Perry Gali , Goldfeld Yiska
Published: March 2022

The paper aims to prove the feasibility of smart concrete pipe systems with integrated monitoring capabilities. The development of such systems is motivated by functional, structural, sustainability and monitoring requirements of underground and buried pipelines with limited accessibility. To answer these challenges, the study adopts the textile reinforced concrete (TRC) technology that allows the production of effective, durable, and lightweight structural elements with integrated monitoring systems. In such systems, by utilizing the electrical conductivity of the carbon rovings, the carbon-based textile can simultaneously serve as the main reinforcement system and as the sensory agent. The proposed hybrid monitoring system aims to detect the occurrence of leakage and to distinguish its severity, which is directly correlated to the structural health. Smart TRC pipes were designed, constructed, and experimentally investigated from structural and sensory points of view. The design considers the multifunctionality of the carbon rovings and the hybrid performance of the textile cage, from both aspects—reinforcement and sensing. An experimental investigation explores the mutual structural, functional, and sensory capabilities of the hybrid system, which reflect and affect each other. It is presented that the strong correlation between the structural-functional and sensory responses reveals an efficient smart TRC pipes. The presented results take a major step toward the realization of the smart TRC concept and exceeded beyond small 1D scale elements to 3D structures.
Sensitivity and bifurcation analysis of pine wilt disease with harmonic mean type incidence rate
Authors: Chawla Sant Ram , Ahmad Saeed , Khan Amir
Published: March 2022

We investigate the characteristics of pine wilt disease by incorporating the harmonic type incident rate in an existing model. We find the threshold number for the model under consideration which plays a vital role in the dynamical behaviour of the system. Stability conditions for the possible stationary states of the system are found in terms of the threshold quantity. Our analysis shows that disease eradicates from the pine trees whenever the threshold quantity assumes values less than unity and persists otherwise. We then study the effect of various parameters of the model upon the spread of the pine wilt disease. The problem presented exhibits bifurcation, an analysis of which is a part of the current work. Under biologically meaningful conditions, we perform numerical simulations to support and verify the analytical findings of this work.
Effects of non-minimal matter-geometry coupling on embedding class-one anisotropic solutions
Authors: Sharif M , Naseer T
Published: March 2022

This paper investigates some particular anisotropic star models in

f
(

,

,

)

gravity, where


=



ω
α



ω
α

. We adopt a standard model

f
(

,

,

)
=

+
ϖ


, where ϖ indicates a coupling constant. We take spherically symmetric spacetime and develop solutions to the modified field equations corresponding to different choices of the matter Lagrangian by applying ‘embedding class-one’ scheme. For this purpose, we utilize

MIT

bag model equation of state and investigate some physical aspects of compact models such as RXJ 1856-37, 4U 1820-30, Cen X-3, SAX J 1808.4-3658 and Her X-I. We use masses and radii of these stars and employ the vanishing radial pressure condition at the boundary to calculate the value of their respective bag constant

B

c

. Further, we fix ϖ = ± 4 to analyze the behavior of resulting state variables, anisotropy, mass, compactness, surface redshift as well as energy bounds through graphical interpretation for each star model. Two different physical tests are performed to check the stability of the developed solutions. We conclude that ϖ = −4 is more suitable choice for the considered modified model to obtain stable structures of the compact bodies.
When does the Schwinger preheating occur?
Authors: Okano So , Fujita Tomohiro
Published: March 2022

When the inflaton couples to photons and amplifies electric fields, charged particles produced via the Schwinger effect can dominate the universe after inflation, which is dubbed as the Schwinger preheating. Using the hydrodynamic approach for the Boltzmann equation, we numerically study two cases, the Starobinsky inflation model with the kinetic coupling and the Watanabe-Kanno-Soda inflation model. The Schwinger preheating is not observed in the latter model but occurs for a sufficiently large inflaton-photon coupling in the first model. We analytically address its condition and derive a general attractor solution of the electric fields. The occurrence of the Schwinger preheating in the first model is determined by whether the electric fields enter the attractor solution during inflation or not.
High-dispersive mirror for pulse stretcher in femtosecond fiber laser amplification system
Authors: Yuan Wenjia , Shen Weidong , Xie Chen , Yang Chenying , Zhang Yueguang
Published: March 2022

We present a high-dispersive multilayer mirror for pulse stretching in a femtosecond fiber laser amplification system. The designed mirror contains 54 layers with a total physical thickness of 7.3 μm, which can provide a positive group delay dispersion (GDD) of 600 fs2 and a high reflectance over 99.9% from 1010 to 1070 nm. The samples were prepared by dual ion beam sputtering. The measured transmittance matches well with the theoretical result. The GDD characteristics of samples were tested by home-made white light interferometer. The measured GDD is higher than the design results, an average GDD of +722 fs2 from 1010 nm to 1070 nm. The mirrors were employed in a Yb-doped large-mode-area photonic crystal fiber amplification system. An input pulse compressed by the gratings with autocorrelation function of 83 fs is obtained with a stretched FWHM of 1.29 ps after 28 bounces between the dispersive mirrors. The results show that the multilayer dispersive mirror could be an effective and promising technique for pulse stretching in femtosecond amplification systems.
Search for correlations between host properties and DM
host of fast radio bursts: constraints on the baryon mass fraction in IGM *
Authors: Lin Hai-Nan , Li Xin , Tang Li
Published: March 2022

The application of fast radio bursts (FRBs) as probes for investigating astrophysics and cosmology requires proper modelling of the dispersion measures of the Milky Way (

) and host galaxy (

).

can be estimated using the Milky Way electron models, such as the NE2001 model and YMW16 model. However,

is hard to model due to limited information on the local environment of the FRBs. In this study, using 17 well-localized FRBs, we search for possible correlations between

and the properties of the host galaxies, such as the redshift, stellar mass, star-formation rate, age of galaxy, offset of the FRB site from the galactic center, and half-light radius. We find no strong correlation between

and any of the host properties. Assuming that

is a constant for all host galaxies, we constrain the fraction of the baryon mass in the intergalactic medium today to be

. If we model

as a log-normal distribution, however, we obtain a larger value,

. Based on the limited number of FRBs, no strong evidence for a redshift evolution of

is found.
Using

as a spin polarimeter *
Authors: Wei Dai-Hui , Yang Yong-Xu , Ping Rong-Gang
Published: March 2022

Polarization transfer measurement plays an important role in the search for new physics processes in charmed baryon decays. The measurement of the

decay is suggested as a spin polarimeter. A general description of the decay is developed using Euler angles, and the polarization parameters are derived. Its relationship with parity violation is found using the phenomenological amplitude model. A Monte-Carlo simulation is performed, and the results show that charmed baryon polarization is well determined using a set of Monte-Carlo events with selected asymmetry parameters. The experimental measurement of these asymmetry parameters is suggested.
ERP prototypical matching net: a meta-learning method for zero-calibration RSVP-based image retrieval
Authors: Wei Wei , Qiu Shuang , Zhang Yukun , Mao Jiayu , He Huiguang
Published: March 2022

Objective. A rapid serial visual presentation (RSVP)-based brain-computer interface (BCI) is an efficient information detection technology through detecting event-related potentials (ERPs) evoked by target visual stimuli. The BCI system requires a time-consuming calibration process to build a reliable decoding model for a new user. Therefore, zero-calibration has become an important topic in BCI research. Approach. In this paper, we construct an RSVP dataset that includes 31 subjects, and propose a zero-calibration method based on a metric-based meta-learning: ERP prototypical matching net (EPMN). EPMN learns a metric space where the distance between electroencephalography (EEG) features and ERP prototypes belonging to the same category is smaller than that of different categories. Here, we employ prototype learning to learn a common representation from ERP templates of different subjects as ERP prototypes. Additionally, a metric-learning loss function is proposed for maximizing the distance between different classes of EEG and ERP prototypes and minimizing the distance between the same classes of EEG and ERP prototypes in the metric space. Main results. The experimental results showed that EPMN achieved a balanced-accuracy of 86.34% and outperformed the comparable methods. Significance. Our EPMN can realize zero-calibration for an RSVP-based BCI system.
63,65Cu, 139La-NMR study of Electron-doped High Temperature Cuprate Superconductor T’-La1.8Eu0.2CuO4–y
F
y
Authors: Fukazawa Hideto , Lee Yongsun , Watai Masaki , Tamura Koma , Ohama Tetsuo , Kohori Yoh , Sunohara Toshiki , Shiosaka Kota , Nagaoka Ryoji , Kawamata Takayuki , Koike Yoji
Published: March 2022

T’-La1.8Eu0.2CuO4–y
F
y
(0 ≤ y ≥ 0.125) was measured by 63,6BCu and 139La NMR. This material is an electron-doped high-Tc cuprate superconductor which has Nd2CuO4-type structure (so-called T’-structure). The nuclear spin-lattice relaxation rate 1/T
1 revealed that pseudogap behavior exists in the lightly electron-doped region of y ≤ 0.075 and electron doping suppresses the antiferromagnetic spin flutuations. These behaviors in electron-doped high-T
c cuprate superconductor are analogous with the optimum- and over-doped region in hole-doped type. 139 La NMR spectra shows almost no antiferromagnetic region in the samples of T’-La1.8Eu0.2CuO4–y
F
y
.
Doping induced band renormalization in 122-type Fe-based superconductor
Authors: Pandeya Ram Prakash , Datta Sawani , Sakhya Anup Pradhan , Saha Tanusree , Ninno Giovanni De , Mondal Rajib , Moras Paolo , Jugovac Matteo , Carbone Carlo , Thamizhavel A , Maiti Kalobaran
Published: March 2022

We study the electronic structure of a superconducting composition of 122-type Fe-based pnictide material, CaFe1.9Co0.1As2 employing high resolution angle resolved photoemission spectroscopy technique. The experimental results exhibit three bands close to Fermi level at Γ-point of the Brillouin zone among which only one band crosses the Fermi level. In the parent compound, CaFe2As2, all the three bands cross the Fermi level and form three hole pockets. While the destruction of Fermi pockets due to electron doping (Co-substitution dopes electrons into the system) is expected, we observe significant orbital selective band renormalization with respect to the parent compound. It appears that the effect of spin-orbit coupling is stronger in the doped compound.
Phase diagram of the three-orbital Hubbard-Holstein model simulating Superconducting Tungsten Bronze AxWO3
Authors: Sekikawa Takuya , Ōno Yoshiaki
Published: March 2022

The superconductivity in tungsten bronze Ax
WO3 (A═alkali metal) is studied based on first-principles calculations and orbital fluctuation theory. We discuss the effects of the electron-Jahn-Teller phonon interaction and the on-site Coulomb interaction in the random phase approximation, and obtain a phase diagram on the U — g plane in the low-doped regime at x~0.05, where high-temperature superconductivity has been experimentally observed.
Phase separation in high-Tccuprates
Authors: Moskvin A S , Panov Yu D
Published: March 2022

We develop a minimal non-BCS model for the CuO2planes with the on-site Hilbert space reduced to only three effective valence centers CuO4with different charge, conventional spin, and orbital symmetry, combined in a charge triplet, to describe the low-energy electron structure and the phase states of HTSC cuprates. Using theS= 1 pseudospin algebra we introduce an effective spin-pseudospin Hamiltonian which takes into account local and nonlocal correlations, one- and two-particle transport, and spin exchange. TheT-nphase diagrams of the complete spin-pseudospin model for the CuO2planes were reproduced by means of a site-dependent variational approach within effective field approximation typical for spin-magnetic systems. Limiting ourselves to two-sublattice approximation andnn-couplings we arrived at several Néel-like phases in CuO2planes for parent and doped systems with a single nonzero local order parameter: antiferromagnetic insulator, charge order, gluelessd-wave Bose superfluid phase, and unusual metallic phase. However, the Maxwell’s construction shows the global minimum of free energy is realized for phase separated states which are bounded by the third-order phase transition lineT*(n), which is believed to be responsible for the onset of the pseudogap phenomenon.
Temperature and doping dependence of the singlet and triplet pair susceptibilities in the one-band Hubbard model based on the dynamical mean-field theory
Authors: Inokuma Yusuke , Ōno Yoshiaki
Published: March 2022

The superconductivity in the one-band Hubbard model on a Bethe lattice is investigated on the basis of the dynamical mean-field theory (DMFT) in which the irreducible vertex function has no k-dependence and then only the s-wave superconductivities with the spin-singlet even-frequency and the spin-triplet odd-frequency pairings are possibly realized. We calculate the pair susceptibility by solving the Bethe-Salpeter equation with the use of the linearized DMFT and find that the spin-singlet pair susceptibility is suppressed by the on-site Coulomb interaction U especially for the region near the Mott transition. On the other hand, the spin-triplet pair susceptibility is apparently enhanced by U in the strong correlation regime at very low temperatures where the effective interaction for the triplet pairing is considered to be attractive and then the triplet superconductivity is expected to be realized.
Joint machine learning analysis of muon spectroscopy data from different materials
Authors: Tula T , Möller G , Quintanilla J , Giblin S R , Hillier A D , McCabe E E , Ramos S , Barker D S , Gibson S
Published: March 2022

Machine learning (ML) methods have proved to be a very successful tool in physical sciences, especially when applied to experimental data analysis. Artificial intelligence is particularly good at recognizing patterns in high dimensional data, where it usually outperforms humans. Here we applied a simple ML tool called principal component analysis (PCA) to study data from muon spectroscopy. The measured quantity from this experiment is an asymmetry function, which holds the information about the average intrinsic magnetic field of the sample. A change in the asymmetry function might indicate a phase transition; however, these changes can be very subtle, and existing methods of analyzing the data require knowledge about the specific physics of the material. PCA is an unsupervised ML tool, which means that no assumption about the input data is required, yet we found that it still can be successfully applied to asymmetry curves, and the indications of phase transitions can be recovered. The method was applied to a range of magnetic materials with different underlying physics. We discovered that performing PCA on all those materials simultaneously can have a positive effect on the clarity of phase transition indicators and can also improve the detection of the most important variations of asymmetry functions. For this joint PCA we introduce a simple way to track the contributions from different materials for a more meaningful analysis.
Shear modulus anomaly of multi-conponent superconductor: the case of Mx
Bi2Se3
Authors: How Pye Ton
Published: March 2022

A pair of split superconducting transitions in the presence of a symmetry breaking field is a very definitive signature of multi-component superconductivity[1, 2]. We theoretically study the shear modulus anomaly across such pair of split transitions[3]. The talk will be focused on MxBi2Se3, a nematic superconductor candidate, for which no experimental confirmation of the split transition has been made so far. We propose that the shear modulus C
66 must vanish at the lower transition: a very clear signature detectable by experiments. The observation of shear modulus anomalies would be a conclusive test for the nematic superconductivity hosted by the material.
Superconducting and chiral-glass to insulator transition in phase-glass models in a magnetic field
Authors: Granato Enzo
Published: March 2022

We investigate the quantum phase transitions of a phase-glass model in a magnetic field with frustration parameter f = 1/2, describing the effects random negative Josephson-junction couplings in two-dimensional superconductors. The critical behavior is obtained by a scaling analysis of path-integral Monte Carlo simulations at zero temperature, including corrections to finite-size scaling. A single superconducting and chiral-glass to insulator transition occurs above a disorder threshold with divergent nonlinear magnetic susceptibility, unaffected by the additional magnetic-field frustration. The relevance of this transition for nanohole superconducting thin films doped with magnetic impurities is discussed.