bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of a continuously extending wall on laminar-turbulent transition in subsonic boundary layers
Authors: Dong Ming
Published: July 2022

Structural morphing is an efficient means to enable the design of aircrafts for diverse requirements, such as high endurance and high speed; however, there may be side effects on the aerodynamic performance, which needs to be considered before its implementation. In this paper, we particularly focus on the impact of a representative morphing structure, a continuously extending wall in the chordwise direction, on the laminar-turbulent transition in subsonic boundary layers. The large-Reynolds-number asymptotic approach is employed, and both the mean-flow distortion and the perturbation field are described by the triple-deck theory, which leads to a great reduction in the number of the controlling parameters and shows clearly their interaction mechanisms. Two relevant mechanisms, namely, the local receptivity and local scattering mechanisms, are considered, whose effects on the development of the boundary-layer instability modes, leading to a change in the transition onset eventually, are quantified systematically by solving numerically the high-dimensional linear equation system. The receptivity efficiency is greater near the lower-branch neutral frequency, while the scattering effect increases with the frequency monotonically. Both the receptivity and scattering calculations show good agreement with the linear predictions when the extending-wall speed is sufficiently low, but for a moderate extending speed, both the receptivity efficiency and the scattering efficiency increase superlinearly with the extending speed.
Numerically “exact” simulations of a quantum Carnot cycle: Analysis using thermodynamic work diagrams
Authors: Koyanagi Shoki , Tanimura Yoshitaka
Published: July 2022

We investigate the efficiency of a quantum Carnot engine based on open quantum dynamics theory. The model includes time-dependent external fields for the subsystems controlling the isothermal and isentropic processes and for the system–bath (SB) interactions controlling the transition between these processes. Numerical simulations are conducted in a nonperturbative and non-Markovian SB coupling regime by using the hierarchical equations of motion under these fields at different cycle frequencies. The work applied to the total system and the heat exchanged with the baths are rigorously evaluated. In addition, by regarding quasi-static work as free energy, we compute the quantum thermodynamic variables and analyze the simulation results by using thermodynamic work diagrams for the first time. Analysis of these diagrams indicates that, in the strong SB coupling region, the fields for the SB interactions are major sources of work, while in other regions, the field for the subsystem is a source of work. We find that the maximum efficiency is achieved in the quasi-static case and is determined solely by the bath temperatures, regardless of the SB coupling strength, which is a numerical manifestation of Carnot’s theorem.
Rheology of Dilute Inertial Suspensions
Authors: Subramanian Ganesh , Marath Navaneeth K.
Published: July 2022

In inertial suspensions, inertia becomes important on the scale of the disperse particulate phase (the ‘micro-scale’). From the rheological standpoint, the interest is in suspensions of neutrally buoyant particles, with micro-scale inertial effects characterized by the particle Reynolds number. Dilute inertial suspensions differ fundamentally from their Stokesian counterparts, in possessing a non-Newtonian rheology and a finite microstructural relaxation time, even in the absence of interparticle interactions. We discuss the role of micro-scale inertia for dilute suspensions of both spherical and anisotropic particles. The discussion on inertial suspensions is preceded by one on Stokesian suspensions, the emphasis being on the rheological indeterminacy arising from either an indeterminate pair-distribution function (spherical particles), or an indeterminate single-particle orientation distribution (spheroidal particles). The effect of inertia is accordingly classified into: (1) a ‘direct effect’ where inertial contributions to rheological properties explicitly involve the particle Reynolds number, and become vanishingly small when the Reynolds number goes to zero; and (2) an ‘indirect effect’ where inertia determines the leading order viscosity, even for vanishingly small Reynolds numbers, due to the Stokesian indeterminacy. As part of the indirect effect, we discuss the tumbling-spinning transition for inertial suspensions of thin oblate spheroids, and the role of stochastic orientation fluctuations in leading to a transition from a shear-thickening to a shearthinning rheology, with changing aspect ratio, for sufficiently long times; and hysteretic behavior for shorter times. While the emphasis is mainly on theoretical calculations for small particle Reynolds numbers, where applicable we discuss simulations that provide insight into inertial effects at finite particle Reynolds number. Although micro-scale inertia is predicted to have profound rheological consequences, measurements of the same pose problems. Traditional rheometric devices are prone to instabilities and secondary flows arising from macro-scale inertia, and we therefore end with a discussion of recent suspension-transition experiments (a non-rheometric setting), that would allow for an inference of the underlying inertial rheology.
Modulation Instability and Non-Degenerate Akhmediev Breathers of Manakov Equations
Authors: Liu Chong , Chen Shao-Chun , Yao Xiankun , Akhmediev Nail
Published: July 2022

We reveal a special subset of non-degenerate Akhmediev breather (AB) solutions of Manakov equations that only exist in the focusing case. Based on exact solutions, we present the existence diagram of such excitations on the frequency-wavenumber plane. Conventional single-frequency modulation instability leads to simultaneous excitation of three ABs with two of them being non-degenerate.
Mechanical characteristics of laminated film vibrator using an ultra-thin MEMS actuator
Authors: Takeshita Toshihiro , Nguyen Thanh-Vinh , Daniel Zymelka , Takei Yusuke , Kobayashi Takeshi
Published: July 2022

This paper describes fabrication of a laminated film vibrator that uses an ultra-thin micro-electric mechanical system (MEMS) and the effect of lamination on the actuator. The thickness of the ultra-thin MEMS actuator fabricated by ultra-thin MEMS technology was 7.26 µm, making it especially flexible. The vibrator was actuated by applying voltage on a lead zirconate titanate (PZT) thin film. Then, we applied a lamination method to package the actuator. However, the lamination structure influenced the mechanical characteristics of the vibrator. Therefore, we evaluated the effect of the lamination structure on the static and dynamic characteristics of the laminated film vibrator. Four types of laminated film vibrators with different layer structures were prepared, and their displacements and velocity were measured when DC and AC voltages were applied. The maximum displacement of the cantilevers constructed from the laminated film vibrator (PZT: 11 mm × 11 mm) was 113.3 µm at 40 V DC. This result is in good agreement with the calculated result. Furthermore, the dynamic characteristics from both the experimental and simulated results confirmed that the resonant frequency of the laminated film vibrator depends on the film structure. This means the dynamic characteristics can be adjusted to suit the application. Applications of this laminated film actuator include use as a flexible hybrid electronics haptic device for monitoring vital signs.
A review of gallium oxide-based power Schottky barrier diodes
Authors: Ji Xueqiang , Lu Chao , Yan Zuyong , Shan Li , Yan Xu , Wang Jinjin , Yue Jianying , Qi Xiaohui , Liu Zeng , Tang Weihua , Li Peigang
Published: July 2022

Gallium oxide (Ga2O3) is a representative of ultra-wide bandgap semiconductors, with a band gap of about 4.9 eV. In addition to a large dielectric constant and excellent physical and chemical stability, Ga2O3 has a theoretical breakdown electric field strength of more than 8 MV cm−1, which is 27 times more than that of Si and about twice as large as that of SiC and GaN. It is guaranteed that Ga2O3 has irreplaceable applications in ultra-high-power (1–10 kW) electronic devices. Unfortunately, due to the difficulty of p-type doping of Ga2O3, the full Ga2O3-based bipolar devices face more difficulties, and the unipolar Ga2O3 power Schottky diodes are feasible, but substantial progress has been made in recent years. In this article, we review the advanced progress and important achievements of the state-of-the-art Ga2O3-based power Schottky barrier diodes, and provide staged guidance for the further development of Ga2O3 power devices. Multiple types of device architectures, including basic structure, edge terminal processing, field-plated, trench and heterojunction p–n structure, will be discussed in detail.
Analysis of a nano-pulsed DBD Plasma jet for endoscopy and impact of excitation parameters
Authors: Bastin Orianne , Thulliez Max , Delchambre Alain , Devière Jacques , Reniers François , Nonclercq Antoine
Published: July 2022

Cold atmospheric plasma induces various dose-dependent effects on living cells, from proliferation to necrosis. These effects are of interest in the field of therapeutic flexible endoscopy, although implementing an effective plasma delivery system represents a technical challenge. This work studies the impact of critical parameters on plume intensity, delivered reactive species (RS), and current administered to the target for the use of plasma in endoscopy. A 2 m long dielectric barrier discharge plasma jet was studied upon nano-pulsed high voltage excitation to increase plasma reactivity. The peak voltage, gas gap, pulse repetition frequency, and pulse width were varied while the power dissipated by the system and the optical emissions (with imaging and spectrometry) were measured. Two configurations were compared: the first one with the plume exiting freely in air, and the second one with the plume impinging an electrical equivalent of the human body. Finally, the current flowing through the capillary was measured at regular intervals along the tube with a Rogowski coil. Results show that (a) a conductive target increases the ratio of RS produced over the dissipated power, (b) increasing the pulse repetition frequency does not improve the RS production per pulse (e.g. through a synergetic, memory effect), (c) increasing the pulse width does not influence RS production but increases the dissipated power, and (d) current linearly leaks through the tube walls, and leaks are lower with nano-pulsed compared to sinusoidal excitation. Reactance and capacitance values of the system are analyzed based on the electrical equivalent circuit approach. Finally, displacement and discharge currents are discussed to bring power dissipation mechanisms to light and compare them between configurations. The conclusions drawn are important for the future design of safe and effective endoscopic plasma devices.
Investigation of empirical heat capacity in hot-rotating A ∼ 200 nuclei
Authors: Xuan Tran Dong , Hung Nguyen Quang , Quynh Huong Le Thi , Cong Vu Duc , Anh Nguyen Ngoc
Published: July 2022

The empirical heat capacities of some hot-rotating A ∼ 200 nuclei (184Re, 200Tl, 211Po, and 212At) have been investigated by combining the angular-momentum dependent back-shifted Fermi gas (BSFG) model of nuclear level density (NLD) with the experimental NLD data extracted from the neutron-evaporation spectra at the average total angular momentum ⟨J⟩ = 12 ℏ. The parameters of the BSFG are obtained by fitting its NLD to the corresponding measured data using an advanced package of program modeling (CPM) provided by Python feature of IBM decision optimization CPLEX. The results obtained show that the shell correction plays an important role in the formation of empirical S-shaped heat capacity, which serves as a fingerprint for the pairing phase transition in finite nuclear systems. The 184Re nucleus, which is deformed and has small shell correction, exhibits a weaker S-shaped heat capacity than the remaining three spherical 200Tl, 211Po, and 212At nuclei that have large shell effects. This result contrasts with that recently predicted by the microscopic exact pairing plus independent-particle model at finite temperature (EP + IPM), in which the S-shaped heat capacity was predicted in 184Re only. This discrepancy between the heat capacities obtained within the BSFG and EP + IPM models suggests that an NLD model capable of well describing the experimental data while also having intrinsic and as complete as possible physical interpretations is still required in order to provide the exact description of nuclear thermodynamic quantities. In addition, more experimental NLD data in other mass and higher energy regions are also demanded.
The Pierre Auger exotic events and axion quark nuggets
Authors: Zhitnitsky Ariel
Published: July 2022

The Pierre Auger observatory have reported (Abreu et al 2021 PoS ICRC2021 p 395; Colalillo 2019 EPJ Web Conf.
197 03003; Colalillo 2017 PoS ICRC2017 p 314) observation of several exotic cosmic ray (CR)-like events which apparently related to thunderstorms. These events are much larger in size than conventional CR events, and they have very distinct timing features. A possible nature of the observed phenomenon is still a matter of active research and debates as many unusual features of these exotic events (EEs) are hard to explain. In particular, the frequency of appearance of these EEs is very low (less than 2 events yr−1), in huge contrast with a typical rate of a conventional lightning strikes in the area. We propose that the observed EEs can be explained within the so-called axion quark nugget (AQN) dark matter model. The idea is that the AQNs may trigger and initiate a special and unique class of lightning strikes during a thunderstorm as a result of ionization of the atmospheric molecules along its path. The corresponding AQN-induced lighting flashes may show some specific features not shared by typical and much more frequent conventional flashes. We support this proposal by demonstrating that the observations (Abreu et al 2021 PoS ICRC2021 p 395; Colalillo 2019 EPJ Web Conf.
197 03003; Colalillo 2017 PoS ICRC2017 p 314), including the frequency of appearance and time duration are consistent with observations. We also comment on possible relation of AUGER EEs with the Telescope Array bursts and the terrestrial gamma ray flashes. We list a number of features of the AQN-induced EEs (such as specific radio pulses synchronized with these events) which can be directly tested by future experiments. We also suggest to use distributed acoustic sensing instruments to detect the acoustic pulses which must be synchronized with AUGER EEs.
Green InP-based quantum dots and electroluminescent light-emitting diodes
Authors: Bian Yangyang , Chen Fei , Shen Huaibin , Du Zuliang
Published: July 2022

With the advancement toward commercialization of quantum dots (QDs) in the field of lighting and display, improving the performance of Cd-free QDs and related quantum dot light-emitting diodes (QLEDs) becomes necessary. Thus far, the performance of ZnTeSe- and InP-based blue and red QLEDs has been significantly improved by optimizing QDs emitting materials and device structure. However, as one of the three primary color sources, the performance of green InP-based QLEDs still lags behind that of blue and red Cd-free QLEDs. Herein, this review discusses the latest progress of green InP-based emitting materials and corresponding QLEDs, covering the engineering of InP core, the optimization of nanostructure and surface ligands of core/shell QDs, as well as the majorization of device architecture and carrier transport materials. Finally, some challenges and possible development directions of green InP-based QDs and related QLEDs are also identified, which may speed up the commercialization process of Cd-free QDs and corresponding QLEDs.
Derivation and analysis of a phase field crystal model for a mixture of active and passive particles
Authors: Vrugt Michael te , Holl Max Philipp , Koch Aron , Wittkowski Raphael , Thiele Uwe
Published: July 2022

We discuss an active phase field crystal (PFC) model that describes a mixture of active and passive particles. First, a microscopic derivation from dynamical density functional theory is presented that includes a systematic treatment of the relevant orientational degrees of freedom. Of particular interest is the construction of the nonlinear and coupling terms. This allows for interesting insights into the microscopic justification of phenomenological constructions used in PFC models for active particles and mixtures, the approximations required for obtaining them, and possible generalizations. Second, the derived model is investigated using linear stability analysis and nonlinear methods. It is found that the model allows for a rich nonlinear behavior with states ranging from steady periodic and localized states to various time-periodic states. The latter include standing, traveling, and modulated waves corresponding to spatially periodic and localized traveling, wiggling, and alternating peak patterns and their combinations.
A unique diffraction pattern formed by a grating from a flying termite wing
Authors: Aji Mahardika Prasetya , Wulandari Yuvita Kiki , Setiawan Rudi , Karunawan Jotti , Priyanto Aan
Published: July 2022

In diffraction experiments, natural gratings often create uncommon diffraction patterns compared with those resulting from manufactured gratings. This study analyzed a unique diffraction pattern obtained by a grating from a flying termite wing. A ring-like diffraction pattern was formed because of the grating morphology from a flying termite wing, which consisted of horizontal- and vertical-structured slits. The mechanism of diffraction pattern formation is also provided. The distance between slits was measured using digital microscope images and a diffraction experiment, with the results coming to an agreement. Using this grating in a diffraction experiment can help educators provide an alternative diffraction experiment that supports students in studying the topic in a more complex manner.
Neumann and Dirichlet boundary conditions for the one-dimensional wave equation
Authors: Williams Hollis
Published: July 2022

The notion of a boundary condition is typically considered to be somewhat advanced and not suitable to be introduced in high school level physics. In this article, we give a simple visual demonstration of the difference between Dirichlet and Neumann boundary conditions for a string which oscillates according to the one-dimensional wave equation. The classical Dirichlet problem for a vibrating string in the plane is mathematically deep, but we will avoid the mathematical issues here and only focus on some key physical points which are relevant for understanding how waves propagate along strings.
Deep morphological recognition of kidney stones using intra-operative endoscopic digital videos
Authors: Estrade Vincent , Daudon Michel , Richard Emmanuel , Bernhard Jean-Christophe , Bladou Franck , Robert Gregoire , Facq Laurent , Denis de Senneville Baudouin
Published: July 2022

Objective. To assess the performance and added value of processing complete digital endoscopic video sequences for the automatic recognition of stone morphological features during a standard-of-care intra-operative session.Approach. A computer-aided video classifier was developed to predict in-situ the morphology of stone using an intra-operative digital endoscopic video acquired in a clinical setting. Using dedicated artificial intelligence (AI) networks, the proposed pipeline selects adequate frames in steady sequences of the video, ensures the presence of (potentially fragmented) stones and predicts the stone morphologies on a frame-by-frame basis. The automatic endoscopic stone recognition (A-ESR) is subsequently carried out by mixing all collected morphological observations.Main results. The proposed technique was evaluated on pure (i.e. include one morphology) and mixed (i.e. include at least two morphologies) stones involving ‘Ia/Calcium Oxalate Monohydrate’ (COM), ‘IIb/Calcium Oxalate Dihydrate’ (COD) and ‘IIIb/Uric Acid’ (UA) morphologies. The gold standard ESR was provided by a trained endo-urologist and confirmed by microscopy and infra-red spectroscopy. For the AI-training, 585 static images were collected (349 and 236 observations of stone surface and section, respectively) and used. Using the proposed video classifier, 71 digital endoscopic videos were analyzed: 50 exhibited only one morphological type and 21 displayed two. Taken together, both pure and mixed stone types yielded a mean diagnostic performances as follows: balanced accuracy = [88 ± 6] (min = 81)%, sensitivity = [80 ± 13] (min = 69)%, specificity = [95 ± 2] (min = 92)%, precision = [78 ± 12] (min = 62)% and F1-score = [78 ± 7] (min = 69)%.Significance. These results demonstrate that AI applied on digital endoscopic video sequences is a promising tool for collecting morphological information during the time-course of the stone fragmentation process without resorting to any human intervention for stone delineation or the selection of adequate steady frames.
FEEDNet: a feature enhanced encoder-decoder LSTM network for nuclei instance segmentation for histopathological diagnosis
Authors: Deshmukh Gayatri , Susladkar Onkar , Makwana Dhruv , Chandra Teja R Sai , Kumar S Nagesh , Mittal Sparsh
Published: July 2022

Objective. Automated cell nuclei segmentation is vital for the histopathological diagnosis of cancer. However, nuclei segmentation from ‘hematoxylin and eosin’ (HE) stained ‘whole slide images’ (WSIs) remains a challenge due to noise-induced intensity variations and uneven staining. The goal of this paper is to propose a novel deep learning model for accurately segmenting the nuclei in HE-stained WSIs. Approach. We introduce FEEDNet, a novel encoder-decoder network that uses LSTM units and ‘feature enhancement blocks’ (FE-blocks). Our proposed FE-block avoids the loss of location information incurred by pooling layers by concatenating the downsampled version of the original image to preserve pixel intensities. FEEDNet uses an LSTM unit to capture multi-channel representations compactly. Secondly, for datasets that provide class information, we train a multiclass segmentation model, which generates masks corresponding to each class at the output. Using this information, we generate more accurate binary masks than that generated by conventional binary segmentation models. Main results. We have thoroughly evaluated FEEDNet on CoNSeP, Kumar, and CPM-17 datasets. FEEDNet achieves the best value of PQ (panoptic quality) on CoNSeP and CPM-17 datasets and the second best value of PQ on the Kumar dataset. The 32-bit floating-point version of FEEDNet has a model size of 64.90 MB. With INT8 quantization, the model size reduces to only 16.51 MB, with a negligible loss in predictive performance on Kumar and CPM-17 datasets and a minor loss on the CoNSeP dataset. Significance. Our proposed idea of generalized class-aware binary segmentation is shown to be accurate on a variety of datasets. FEEDNet has a smaller model size than the previous nuclei segmentation networks, which makes it suitable for execution on memory-constrained edge devices. The state-of-the-art predictive performance of FEEDNet makes it the most preferred network. The source code can be obtained from https://github.com/CandleLabAI/FEEDNet.
Performance evaluation of piezo sensors with respect to accelerometers for 3D modal analysis of structures
Authors: Aulakh Dattar Singh , Bhalla Suresh
Published: July 2022

Strain modal analysis, as a new domain in the health monitoring field, needs to be studied in depth for experimental modal testing. Towards this purpose, this paper experimentally investigates the efficacy of piezo sensors for structural identification for structural health monitoring under different excitations applicable to large-scale structures. The piezo sensors are evaluated against industry-standard accelerometers by experimental modal testing of a scaled-down model of a pedestrian foot over bridge. The model is excited under the impact hammer, electro-dynamic shaker-based sweep and random excitations, and pedestrian motion (PM)-based low-amplitude excitations. Piezo sensors are found to be capable of capturing the modal parameters (modal frequencies, damping ratios and mode shape vector) under all the excitations with excellent correlation with respect to accelerometer-based parameters. However, some modes are missed under the shaker and PM-based excitations compared to the impact hammer-based excitations for both accelerometers and piezo sensors. Modal parameters of lower modes are successfully extracted under low-level pedestrian excitations, the most efficient type of excitation acting in operational conditions. High modal assurance criteria values between the strain and the displacement mode shapes establish the piezo sensors as effective for strain-based vibration testing and structural identification.
Influence of growth temperature on the pinning landscape of YBa2Cu3O7−

δ
films grown from Ba-deficient solutions
Authors: Alcalà Jordi , Ternero Pau , Pop Cornelia , Piperno Laura , Ricart Susagna , Mestres Narcís , Puig Teresa , Obradors Xavier , Meledin Alexander , Celentano Giuseppe , Palau Anna
Published: July 2022

Cuprate coated conductors are promising materials for the development of large-scale applications, having superior performance over other superconductors. Tailoring their vortex pinning landscape through nanostructure engineering is one of the major challenges to fulfill the specific application requirements. In this work, we have studied the influence of the growth temperature on the generation of intrinsic pinning defects in YBa2Cu3O7−δ
films grown by chemical solution deposition using low Ba precursor solutions. We have analysed the critical current density as a function of the temperature, applied magnetic field magnitude and orientation, J
c(T,H,θ), to elucidate the nature and strength of pinning sites and correlate the microstructure of the films with their superconducting performance. An efficient pinning landscape consisting of stacking faults and associated nanostrain is naturally induced by simply tuning the growth temperature without the need to add artificial pinning sites. Samples grown at an optimized temperature of 750 °C show very high self-field J
c values correlated with an overdoped state and improved J
c(T,H,θ) performances.
Suppression of fibrillatory dynamics consisting of stable rotors by periodic pacing
Authors: Buran Pavel , Niedermayer Thomas , Bär Markus
Published: July 2022

Recent experimental studies have shown that a sequence of low-energy electrical far-field pulses is able to terminate fibrillation with substantially lower per-pulse energy than a single high-energy electric shock (see S Luther et al Nature
475 235–39). During this low-energy antifibrillation pacing (LEAP) procedure only tissue near sufficiently large conduction heterogeneities, such as large coronary arteries, is activated. In order to understand the mechanism behind LEAP, we have carried out a statistical study of resetting a medium filled by one or more stable spirals (‘rotors’) in a two-dimensional electrophysiological model of cardiac tissue perforated by blood vessels to the resting state (‘defibrillation’). We found the highest success probabilities for this defibrillation for underdrive pacing with periods 10–20 percent larger than the dominant period of the stable rotors in the unperturbed dynamics. If a sufficiently large number pulses is applied and an optimal pacing period chosen, the energy per pulse required for successful defibrillation is about 75–80 percent lower than the energy needed for single-shock defibrillation. Optimal conditions to control and suppress fibrillation based on stable rotors, hence, are similar to the ones in found for the case of an electrophysiological model displaying spatiotemporal chaos (‘electrical turbulence’) in an earlier study (see P Buran et al 2017 Chaos
27 113110). The optimal pacing period is found to increase with increasing strength of the electrical field strength used in the model. The success probability also increases strongly until the fourth or fifth pulse administered, which is strongly correlated to an observed increase of the fraction of re-excitable tissue with each subsequent pulse. Monitoring the fraction of excitable tissue in the model as key quantity of the excitable medium, moreover, enabled us to successfully predict the optimal pacing period for defibrillation.
Overview of initial negative triangularity plasma studies on the ASDEX Upgrade tokamak
Authors: Happel T. , Pütterich T. , Told D. , Dunne M. , Fischer R. , Hobirk J. , McDermott R.M. , Plank U. , the ASDEX Upgrade Team
Published: July 2022

An overview of results of negative triangularity (NT) studies from the ASDEX Upgrade tokamak (AUG) is given. Moderate values of the triangularity in the range of δ
average ≈ −0.2 have been obtained. Results from both unfavorable and favorable magnetic configuration in terms of high-confinement mode (H-mode) access are presented. In unfavorable configuration, the ion grad B drift points away from the active x-point, which usually results in a factor of 2 higher power thresholds to enter H-mode. In unfavorable configuration, low-confinement mode (L-mode) operation is confirmed at high auxiliary heating input powers

>
10

MW at low collisionality. Under these conditions, plasmas with positive triangularity (PT) are usually in H-mode. Highest plasma energies have been obtained using a combination of neutral beam injection, electron- and ion cyclotron resonance heating, where values of the plasma beta of β
N ≈ 1.7 have been reached in L-mode. While discharges with mixed auxiliary heating power input show moderate confinement on L-mode levels, plasmas heated with electron cyclotron resonance heating show H-mode like confinement. Operation in favorable configuration, however, leads to H-mode with type-I edge localized modes (ELMs). The power required for the L–H transition is comparable to the typical L–H power threshold in PT cases (

<
2.6

MW), and good confinement of typical PT H-modes is obtained. The ELM frequency is demonstrated to reach 700 Hz. These results show a clear effect of the NT configuration on the ELM behavior in H-modes, and that on AUG, unfavorable configuration is an essential ingredient if H-mode operation is to be avoided in NT plasmas. So far, in all AUG NT plasmas, power degradation is observed. Initial gyrokinetic simulations of the edge plasma in unfavorable configuration reveal the ion-temperature gradient mode as the fastest growing mode with a subdominant trapped-electron-mode.
Modeling of the effects of impurity seeding on plasma detachment and impurity screening of snowflake divertor on HL-2M tokamak by SOLPS-ITER
Authors: Zhang Yanjie , Sang Chaofeng , Li Jiaxian , Zheng Guoyao , Senichenkov Ilya Y. , Rozhansky Vladimir A. , Zhang Chen , Wang Yilin , Zhao Xuele , Wang Dezhen
Published: July 2022

To address the issues of mitigation and control of the heat loads on the divertor target, a snowflake divertor (SFD) has been proposed on the HL-2M tokamak. In this work, simulations have been performed by using SOLPS-ITER to demonstrate the advantages of SFD on HL-2M on plasma detachment and impurity screening during impurity seeding. Firstly, neon (Ne) and argon (Ar) seeding are chosen for comparison in SFD. It is found that Ar seeding significantly mitigates the in-out asymmetry compared with Ne seeding, mainly in high seeding rate cases. The impurity screening capabilities with Ar seeding are conspicuously better than that of Ne seeding. Subsequently, the SFD and standard divertor (SD) with Ar seeding are compared. The SFD achieves plasma detachment with a seeding rate of more than one order of magnitude lower and has better impurity screening capability than those of the SD. This can be explained by more substantial Ar accumulation in the private flux region near the X-point in SD. Moreover, the simulation shows that D2 puffing near the OMP can drive more Ar ions to the divertor and promote the plasma detachment and impurity screening. Finally, the effects of E × B drift on SFD are studied. It is found that with E × B drift more Ar particles accumulate in the vicinity of both inner and outer targets, especially in the far-SOL region, thus raising the far-SOL power radiation. However, the peak heat flux is mainly located near the separatrix, therefore a higher seeding rate is required to achieve detachment. Moreover, the E × B drift drives more Ar particles away from the core region. In addition, the role of molecules on the plasma momentum loss during detachment is analyzed.
Normal mode splitting and four-wave mixing in Kerr-nonlinear optical system containing coupled double quantum dot
Authors: Bhatt Vijay , Yadav Surabhi , Jha Pradip K , Bhattacherjee Aranya B
Published: July 2022

We theoretically investigate the four wave mixing (FWM) and normal mode splitting (NMS) in coupled double quantum dots cavity system in the presence of a third-order Kerr nonlinear

χ

(
3
)

medium. The FWM generated in the system has narrow spectral width and this can be tuned by nonlinear medium strength, the coupling strength between two coupled quantum dots and pump strength. Further, we study NMS that can also be tuned by various physical parameters and show that energy exchange between different modes is possible. The proposed model have potential applications in the field of quantum information processing.
Comparative estimation of pleural effusion volume based on lateral decubitus position of chest x-ray and CT scan imaging
Authors: Satoto Bambang , Budi Wahyu S , Khumaeni Ali , Yueniwati Yuyun , Noorhamdani Noorhamdani
Published: July 2022

Previous study using thoracic phantom for estimating fluid volume has been obtained which represents the case of pleural effusion based on the size of the x-ray radiograph. The models are obtained in the form of three equations, the pleural effusion volume as a function of height, length times the height, and area of the radiograph image. The three models of estimation have high linearity with ratio value more than 0.988, higher than the modelling measurement using ultrasonography modality. The modelling is expected to give a contribution on developing method for helping clinicians estimate the pleural effusion volume as a basic for performing fluid aspiration and to monitor the therapy. However, because modelling is developed using phantoms, then to be applied clinically, further research is needed for its application to patients. The height function model yields correlation value of 0.966 and paired T-test value of 0.892. The height times length function model yields correlation value of 0.982 and paired T-test value of 0.611. The area function model yields correlation value of 0.997 and paired T-test value of 0.647. From the three equations, measurement of estimated pleural effusion volume using area function on chest x-ray lateral decubitus position is the most appropriate equation. Corresponding to the results of the measurement of gold standard using a CT scan. Height measurement is the measurement that is the fastest and easiest in the application. Limitation of the study is it only can be done in right lateral decubitus position of the patient, and also cannot be applied to patients with condition such as post lung surgery, massive subpulmonic/ supradiaphragmatic pleural effusion, empyema, an atypical pleural effusion such as septated, encapsulated, loculated pleural effusion and anatomical deformity, scoliosis, or abnormalities of thoracic cavity.
MIB2: metal ion-binding site prediction and modeling server
Authors: Lu Chih-Hao , Chen Chih-Chieh , Yu Chin-Sheng , Liu Yen-Yi , Liu Jia-Jun , Wei Sung-Tai , Lin Yu-Feng
Published: July 2022

Motivation

MIB2 (metal ion-binding) attempts to overcome the limitation of structure-based prediction approaches, with many proteins lacking a solved structure. MIB2 also offers more accurate prediction performance and more metal ion types.

Results

MIB2 utilizes both the (PS)2 method and the AlphaFold Protein Structure Database to acquire predicted structures to perform metal ion docking and predict binding residues. MIB2 offers marked improvements over MIB by collecting more MIB residue templates and using the metal ion type-specific scoring function. It offers a total of 18 types of metal ions for binding site predictions.

Availability and implementation

Freely available on the web at http://bioinfo.cmu.edu.tw/MIB2/.

Supplementary information

Supplementary data are available at Bioinformatics online.
tmVar 3.0: an improved variant concept recognition and normalization tool
Authors: Wei Chih-Hsuan , Allot Alexis , Riehle Kevin , Milosavljevic Aleksandar , Lu Zhiyong
Published: July 2022

Motivation

Previous studies have shown that automated text-mining tools are becoming increasingly important for successfully unlocking variant information in scientific literature at large scale. Despite multiple attempts in the past, existing tools are still of limited recognition scope and precision.

Result

We propose tmVar 3.0: an improved variant recognition and normalization system. Compared to its predecessors, tmVar 3.0 recognizes a wider spectrum of variant-related entities (e.g. allele and copy number variants), and groups together different variant mentions belonging to the same genomic sequence position in an article for improved accuracy. Moreover, tmVar 3.0 provides advanced variant normalization options such as allele-specific identifiers from the ClinGen Allele Registry. tmVar 3.0 exhibits state-of-the-art performance with over 90% in F-measure for variant recognition and normalization, when evaluated on three independent benchmarking datasets. tmVar 3.0 as well as annotations for the entire PubMed and PMC datasets are freely available for download.

Availability and implementation

https://github.com/ncbi/tmVar3
Marginal structural models for multilevel clustered data
Authors: Wu Yujie , Langworthy Benjamin , Wang Molin
Published: July 2022

Marginal structural models (MSMs), which adopt inverse probability treatment weighting in the estimating equations, are powerful tools to estimate the causal effects of time-varying exposures in the presence of time-dependent confounders. Motivated by the Conservation of Hearing Study (CHEARS) Audiology Assessment Arm (AAA) where repeated hearing measurements were clustered by study participants, time, and testing sites, we propose two methods to account for the multilevel correlation structure when fitting the MSMs. The first method directly models the covariance of the repeated outcomes when solving the weighted generalized estimating equations for MSMs, while the second two-stage analysis approach fits cluster-specific MSMs first and then combines the estimated parameters using mixed-effects meta-analysis. Finite sample simulation results suggest that our methods can obtain less biased and more efficient estimates of the parameters by accounting for the multilevel correlation. Moreover, we explore the effects of using fixed- or mixed-effects model to estimate the treatment probability on the parameter estimates of the MSMs in the presence of unmeasured cluster-level confounders. Lastly, we apply our methods to the CHEARS AAA data set, to estimate the causal effects of aspirin use on hearing loss.
Prognostic value of exosomal noncoding RNA in hepatocellular carcinoma: a meta-analysis
Authors: Nie Guilin , Lian Nan , Peng Dingzhong , Lu Jiong , Li Bei
Published: July 2022

High morbidity, recurrence and mortality make hepatocellular carcinoma (HCC) a leading cause of cancer-related burden and deaths. The lack of prognostic evaluation methods weakened the therapeutic efficacy for HCC. Exosomal noncoding RNAs (ncRNAs) play a key role in cancer development. Our meta-analysis aimed to assess the prognostic value of exosome-transferred noncoding RNAs in predicting the outcomes of patients with HCC. We obtained 16 articles from PubMed, Web of Science, Scopus, and EMBASE up to 4 November 2021. The ncRNAs were divided into three parts: microRNAs (miRNA), long noncoding RNAs (lncRNA), and circular RNAs (circRNA). In the pooled hazard ratios (HRs), upregulated miRNAs were 3.06 (95% CI = 2.51–3.73), downregulated miRNAs were 3.28 (95% CI = 2.61–4.11), lncRNAs were 3.34 (95% CI = 1.87–5.96), and circRNAs were 1.76 (95% CI = 1.36–2.14). As the results of subgroup analysis, upregulated miRNAs had a pooled HR of 3.10 (95% CI = 1.66–5.81), and the HR of downregulated miRNAs was 3.04 (95% CI = 2.17–4.28) for multivariate analysis of overall survival (OS). Meanwhile, upregulated miRNAs had a pooled HR of 2.61 (95% CI = 1.89–3.60), and the HR of downregulated miRNAs was 3.77 (95% CI = 1.11–12.73) for multivariate analysis of other endpoints. Remarkably, miR-21 has a pooled HR of 2.48 (95%CI = 1.52–4.05, I2 = 0) for disease-free survival (DFS). In conclusion, the expression of exosomal noncoding RNAs can be used to evaluate the prognosis of patients with HCC. Exosome-transferred miR-21 might serve as a potential prognostic biomarker in HCC.
Pneumonia, Meningitis, and Septicemia in Adults and Older Children in Rural Gambia: 8 Years of Population-Based Surveillance
Authors: Green Edward W , Ndiaye Malick , Hossain Ilias M , Olatunji Yekini A , Sahito Shah M , Salaudeen Rasheed , Badji Henry , Manjang Ahmed , Ceesay Lamin , Hill Philip C , Greenwood Brian , Mackenzie Grant A
Published: July 2022

Background

Representative data describing serious infections in children aged ≥5 years and adults in Africa are limited.

Methods

We conducted population-based surveillance for pneumonia, meningitis, and septicemia in a demographic surveillance area in The Gambia between 12 May 2008 and 31 December 2015. We used standardized criteria to identify, diagnose, and investigate patients aged ≥5 years using conventional microbiology and radiology.

Results

We enrolled 1638 of 1657 eligible patients and investigated 1618. Suspected pneumonia, septicemia, or meningitis was diagnosed in 1392, 135, and 111 patients, respectively. Bacterial pathogens from sterile sites were isolated from 105 (7.5%) patients with suspected pneumonia, 11 (8.1%) with suspected septicemia, and 28 (25.2%) with suspected meningitis. Streptococcus pneumoniae (n = 84), Neisseria meningitidis (n = 16), and Staphylococcus aureus (n = 15) were the most common pathogens. Twenty-eight (1.7%) patients died in hospital and 40 (4.1%) died during the 4 months after discharge. Thirty postdischarge deaths occurred in patients aged ≥10 years with suspected pneumonia. The minimum annual incidence was 133 cases per 100 000 person-years for suspected pneumonia, 13 for meningitis, 11 for septicemia, 14 for culture-positive disease, and 46 for radiological pneumonia. At least 2.7% of all deaths in the surveillance area were due to suspected pneumonia, meningitis, or septicemia.

Conclusions

Pneumonia, meningitis, and septicemia in children aged ≥5 years and adults in The Gambia are responsible for significant morbidity and mortality. Many deaths occur after hospital discharge and most cases are culture negative. Improvements in prevention, diagnosis, inpatient, and follow-up management are urgently needed.
Hepatitis C Virus Infection Preceding an Outbreak of Human Immunodeficiency Virus Among Persons Who Inject Drugs—Kanawha County, West Virginia, 2019–2021
Authors: Hudson Alana G , Bonacci Robert A , Moorman Anne C , Penley McKenna , Wilson Suzanne M , Hoffman Jessica L , Thomasson Erica R , McClung R Paul , Bixler Danae
Published: July 2022

Of 65 cases during a human immunodeficiency virus (HIV) outbreak among persons who inject drugs (PWID) in West Virginia (2019–2021), 61 (94%) had hepatitis C diagnosed a median of 46 months prior to HIV diagnosis. Hepatitis C diagnosis among PWID should trigger improved access to prevention and treatment services.
On Target? Sanctions and the Economic Interests of Elite Policymakers in Iran
Authors: Draca Mirko , Garred Jason , Stickland Leanne , Warrinnier Nele
Published: July 2022

How successful are sanctions at targeting the economic interests of political elites in affected countries? We study the case of Iran, using information on the stock exchange-listed assets of two specific political entities with significant influence over the direction of Iran’s nuclear programme. Our identification strategy focuses on the process of negotiations for sanctions removal, examining which interests benefit most from news about diplomatic progress. The results indicate the ‘bluntness’ of sanctions on Iran, but also provide evidence of their effectiveness in generating substantial economic incentives for elite policymakers to negotiate a deal for sanctions relief.
An off-pump biatrial mini-maze procedure for long-standing persistent atrial fibrillation
Authors: Yan Tao , Zhu Shijie , Chen Nan , Zhu Miao , Zhu Kai , Wei Lai , Wang Chunsheng , Guo Changfa
Published: July 2022

OBJECTIVES

The goal of the present study was to determine the safety and efficacy of a modified off-pump biatrial mini-maze procedure to treat long-standing persistent atrial fibrillation (AF).

METHODS

Patients with long-standing persistent AF underwent our modified mini-maze procedure using bipolar radiofrequency ablation. Those patients first underwent a mini-maze procedure using the Dallas lesion set protocol. Second, a purse-string suture was performed on the right atrium, and then 4 ablation lesions were made to the superior vena cava, the inferior vena cava, the appendix of the right atrium and the tricuspid valve annulus from the purse-string suture point by the bipolar radiofrequency clamp. After the operation, the patients were followed up at 3, 6 and 12 months and every year thereafter.

RESULTS

A total of 102 patients were included in the study. There were no deaths, no surgical re-exploration for bleeding and no permanent pacemaker implants. The intraoperative cardioversion rate was 42.2% (43/102). A follow-up at intervals of 3, 6, 12, 24, 36 and 48 months showed that a success rate free from long-standing persistent AF was 95.1% (97/102), 94.4% (85/90), 94.8% (73/77), 91.5% (54/59), 90.3% (28/31) and 86.4% (19/22), whereas freedom from AF in patients off antiarrhythmic drugs was 88.2% (90/102), 85.6% (77/90), 81.8% (63/77), 78.0% (46/59), 74.2% (23/31) and 68.2% (15/22), respectively.

CONCLUSIONS

The modified biatrial mini-maze procedure proved to be safe and feasible. Early follow-up demonstrated an acceptable success rate free from AF.