bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of mass ablation on ignition and burn propagation in layered fusion capsules
Authors: Daughton W. , Albright B. J. , Finnegan S. M. , Haines Brian M. , Kline J. L. , Sauppe J. P. , Smidt J. M.
Published: January 2023

After decades of research, recent laser-driven inertial fusion experiments have demonstrated rapid progress toward achieving thermonuclear ignition using capsule designs with cryogenic fuel layers. The ignition physics for these layered capsules involves a complex interplay between the dynamically forming hot spot and the dense surrounding fuel. Using analytic theory and numerical simulations, we demonstrate that the mass ablation rate into the hot spot depends sensitively upon the temperature of the dense fuel, resulting in ablative inflows up to 4× faster than previous estimates. This produces an enthalpy flux into the hot spot that plays a critical role in controlling the hot spot temperature, the ignition threshold, and the subsequent burn propagation. The net influence of mass ablation on the ignition threshold is regulated by a dimensionless parameter that depends upon the temperature of the dense fuel. As a consequence, the ignition threshold is sensitive to any mechanism that heats the dense fuel, such as neutrons or radiation emitted from the hot spot. These predictions are confirmed using radiation-hydrodynamic simulations for a series of capsules near ignition conditions. This analysis may have relevance for understanding the variable performance of recent experiments and for guiding new capsule designs toward higher fusion yields.
A reconfigurable polarization converter and related application as horn antenna cladding
Authors: Zhu Shuang Shuang , Wang Ping , Zhang Yong , Yan Zhong Ming , Wang Yu , Zhou Hong Cheng
Published: January 2023

In this paper, a transmissive reconfigurable polarization converter (RPC) based on an active metasurface is proposed, which can regulate the ideal plane wave and the spherical wave as a cladding of the horn antenna. The metasurface unit is composed of a single-layer F4B dielectric substrate and two double-cross metal strips with a p–i–n diode on the top and seven vertical metal strips on the bottom. One RPC prototype with 15 × 15 units has been fabricated and measured when it regulates an ideal plane wave. By controlling the states of diodes, the RPC can realize the linear-to-circular polarization conversion (LCPC) or the linear polarization maintaining (LPM) function from 2.5 to 3.64 GHz. Furthermore, the RPC is used as the cladding of a horn antenna for high integration in practical applications. The measured results show that this RPC-antenna system can still achieve LCPC or LPM function from 3.1 to 4.5 GHz. It is worth mentioning that the 3 dB axial ratio beam width of RPC can cover from −65° to 65° in LCPC. The proposal has advantages of a wideband, simple biasing network, and easy fabrication and integration, which can be widely applied in modern wireless communication systems.
Mechanism of enhanced critical fields and critical current densities of MgB2 wires with C/Dy2O3 co-additions
Authors: Wan F. , Sumption M. D. , Collings E. W.
Published: January 2023

A series of monofilamentary powder-in-tube MgB2 wires were fabricated with 2 mol. % C doping and co-additions of 0–3 wt. % Dy2O3. Irreversibility fields (μ0Hirr), upper critical fields (μ0Hc2), and transport critical currents were measured, and from these quantities, anisotropies (γ) and electronic diffusivities (Dπ,σ) were estimated. The addition of 1 wt. % Dy2O3 to already optimally C-doped MgB2 wires produced higher Hc2//ab, Hc2//c, and Hirr values at 4.2 K. In addition, the critical current density, Jc, increased with Dy2O3 concentration up to 1 wt. % where non-barrier Jc reached 4.35 × 104 A/cm2 at 4.2 K, 10 T. At higher temperatures, for example, 20 K and 5 T, co-additions of 2 mol. % C and 2 wt. % Dy2O3 improved non-barrier Jc by 40% and 93% compared to 2 and 3 mol. % C doping, respectively. On the other hand, measurements of Tc showed that C/Dy2O3 co-additions increase interband scattering rates at a lower rate than C doping does (assuming C doping levels giving similar levels of low-T μ0Hc2 increase as co-addition). Comparisons to a two-band model for μ0Hc2 in MgB2 allowed us to conclude that the increases in Hc2//ab, Hc2//c, and Hirr (as well as concomitant increases in high-field Jc) with Dy2O3 addition are consistent with increases primarily in intraband scattering. This suggests C/Dy2O3 co-addition to be a more promising candidate for improving non-barrier Jc of MgB2 at temperatures above 20 K.
Enhanced terahertz third-harmonic generation in graphene–metal metasurface with bound states in the continuum
Authors: Wang Baoku , Liu Jing , Liu Jialin , Liu Jianlong , Liu Jianqiang , Sun Weimin , Li Li
Published: January 2023

We propose a graphene–metal metasurface with bound states in the continuum (BICs) for the enhancement of terahertz (THz) third-harmonic generation (THG). With the adjustment of graphene Fermi level, the parameter-tuned BICs produced by the graphene–metal metasurface can make the transition to distinct quasi-BICs. It enables strong confinement of the localized field in monolayer graphene. By exploiting the large third-order nonlinearity of graphene, the efficient THG process at the quasi-BICs can be boosted under low pump threshold. With the 50 kW/cm2 of fundamental THz incidence, a THG conversion efficiency as high as ∼3% is achievable at the quasi-BICs regime. This renders the BIC metasurfaces very attractive for THz nonlinear photonics.
Understanding non-covalent interactions of graphene oxide toward transition metal surfaces and relation of binding constants with titration end points from dynamic light scattering studies
Authors: Ayoub Muhammad Haris , Ahmad Shehryar , Hassan Zia Ul , Khan Asad Muhammad , Bilal Muhammad , Waseem Amir , Shaikh Ahson Jabbar
Published: January 2023

The understanding of non-covalent binding interactions of graphene oxide toward transition metal surfaces (Fe, Co, Ni, and Cu) was observed by ultraviolet–visible absorption spectroscopy, fluorescence emission spectroscopy, hydrodynamic size, and zeta potential studies through titration experiments. These interactions mainly occur through C=C double bonds of graphene oxide. Iron and cobalt nanoparticles interact strongly as compared to nickel and copper nanoparticles. The obtained Stern–Volmer plots are curved indicating that static and dynamic quenching occur simultaneously in these systems. The curves obtained for size titration graphs indicated the saturation end point for these titrations, which were then compared with binding constants obtained from linear Stern–Volmer plots. Interestingly, with lower binding constants, a higher concentration of nanoparticles was required for titration end points. These two complimentary techniques stood well quantitatively toward each other. Upon titrating the nanoparticles with graphene oxide, the zeta potential always lowered close to the value of graphene oxide, indicating that hybrids are more stable than the nanoparticles.
Polytropic representation of the kinetic pressure tensor of non-ideal magnetized fluids in equilibrium toroidal structures
Authors: Cremaschini Claudio , Kovář Jiří , Stuchlík Zdeněk , Tessarotto Massimo
Published: January 2023

Non-ideal fluids are generally subject to the occurrence of non-isotropic pressure tensors, whose determination is fundamental in order to characterize their dynamical and thermodynamical properties. This requires the implementation of theoretical frameworks provided by appropriate microscopic and statistical kinetic approaches in terms of which continuum fluid fields are obtained. In this paper, the case of non-relativistic magnetized fluids forming equilibrium toroidal structures in external gravitational fields is considered. Analytical solutions for the kinetic distribution function are explicitly constructed, to be represented by a Chapman–Enskog expansion around a Maxwellian equilibrium. In this way, different physical mechanisms responsible for the generation of non-isotropic pressures are identified and proved to be associated with the kinetic constraints imposed on single and collective particle dynamics by phase-space symmetries and magnetic field. As a major outcome, the validity of a polytropic representation for the kinetic pressure tensors corresponding to each source of anisotropy is established, whereby directional pressures exhibit a specific power-law functional dependence on fluid density. The astrophysical relevance of the solution for the understanding of fluid plasma properties in accretion-disk environments is discussed.
Relativistic two-electron atomic and molecular energies using LS coupling and double groups: Role of the triplet contributions to singlet states
Authors: Jeszenszki Péter , Mátyus Edit
Published: January 2023

The triplet contribution is computed to the 1 and 2 [Formula: see text] states of the He atom, to the [Formula: see text] state of the Li+ and Be2+ ions, and to the [Formula: see text] ground state of the H2 molecule by extensive use of double-group symmetry (equivalent to LS coupling for the atomic systems) during the course of the variational solution of the no-pair Dirac–Coulomb–Breit (DCB) wave equation. The no-pair DCB energies are converged within sub-parts-per-billion relative precision, using an explicitly correlated Gaussian basis optimized to the non-relativistic energies. The α fine-structure constant dependence of the triplet sector contribution to the variational energy is α4 Eh at leading order, in agreement with the formal perturbation theory result available from the literature.
Analytical potential energy surface and dynamics for the OH + CH3OH reaction
Authors: Espinosa-Garcia J. , Rangel C.
Published: January 2023

Using as functional form a combination of valence bond and mechanic molecular terms a new full-dimensional potential energy surface was developed for the title reaction, named PES-2022, which was fitted to high-level ab initio calculations at the coupled-cluster singles, doubles, and perturbative triples-F12 explicitly correlated level on a representative number of points describing the reactive system. This surface simultaneously describes the two reaction channels, hydrogen abstraction from the methyl group [(R1) path] and from the alcohol group [(R2) path] of methanol to form water. PES-2022 is a smooth and continuous surface, which reasonably describes the topology of this reactive system from reactants to products, including the intermediate complexes present in the system. Based on PES-2022 an exhaustive dynamics study was performed using quasi-classical trajectory calculations under two different initial conditions: at a fixed room temperature, for direct comparison with the experimental evidence and at different collision energies, to analyze possible mechanisms of reaction. In the first case, the available energy was mostly deposited as water vibrational energy, with the vibrational population inverted in the stretching modes and not inverted in the bending modes, reproducing the experimental evidence. In the second case, the analysis of different dynamics magnitudes (excitation functions, product energy partitioning, and product scattering distributions), allows us to suggest different mechanisms for both (R1) and (R2) paths: a direct mechanism for the (R2) path vs an indirect one, related with “nearly trapped” trajectories in the intermediate complexes, for the (R1) path.
Fine-structure excitation of CCS by He: Potential energy surface and scattering calculations
Authors: Godard Palluet A. , Lique F.
Published: January 2023

The fine structure excitation of the interstellar CCS radical induced by collisions with He is investigated. The first potential energy surface (PES) for the CCS–He van der Waals complex is presented. It was obtained from a highly correlated spin unrestricted coupled cluster approach with single double and perturbative triple excitations. The PES presents two shallow minima of 31.85 and 37.12 cm−1 for the linear (He facing S) and the nearly T-shaped geometries, respectively. The dissociation energy of the complex was calculated and found to be D0 = 14.183 cm−1. Inelastic scattering calculations were performed using the close-coupling approach. Cross-sections for transitions between the 61 first fine structure levels of CCS were obtained for energy up to 600 cm−1 and rate coefficients for the 5–50 K temperature range were derived. This set of collisional data can be used to model CCS emission spectra in dark molecular interstellar clouds and circumstellar envelopes and enable an accurate determination of CCS abundance in these astrophysical media.
Introduction to Focus Issue: Dynamics of oscillator populations
Authors: Pikovsky Arkady , Rosenblum Michael
Published: January 2023

Even after about 50 years of intensive research, the dynamics of oscillator populations remain one of the most popular topics in nonlinear science. This Focus Issue brings together studies on such diverse aspects of the problem as low-dimensional description, effects of noise and disorder on synchronization transition, control of synchrony, the emergence of chimera states and chaotic regimes, stability of power grids, etc.
The synaptic organization in the
Caenorhabditis elegans
neural network suggests significant local compartmentalized computations
Authors: Ruach Rotem , Ratner Nir , Emmons Scott W. , Zaslaver Alon
Published: January 2023

Neurons are characterized by elaborate tree-like dendritic structures that support local computations by integrating multiple inputs from upstream presynaptic neurons. It is less clear whether simple neurons, consisting of a few or even a single neurite, may perform local computations as well. To address this question, we focused on the compact neural network of
Caenorhabditis elegans
 animals for which the full wiring diagram is available, including the coordinates of individual synapses. We find that the positions of the chemical synapses along the neurites are not randomly distributed nor can they be explained by anatomical constraints. Instead, synapses tend to form clusters, an organization that supports local compartmentalized computations. In mutually synapsing neurons, connections of opposite polarity cluster separately, suggesting that positive and negative feedback dynamics may be implemented in discrete compartmentalized regions along neurites. In triple-neuron circuits, the nonrandom synaptic organization may facilitate local functional roles, such as signal integration and coordinated activation of functionally related downstream neurons. These clustered synaptic topologies emerge as a guiding principle in the network, presumably to facilitate distinct parallel functions along a single neurite, which effectively increase the computational capacity of the neural network.
Neuronal membrane proteasomes regulate neuronal circuit activity in vivo and are required for learning-induced behavioral plasticity
Authors: He Hai-yan , Ahsan Arifa , Bera Reshmi , McLain Natalie , Faulkner Regina , Ramachandran Kapil V. , Margolis Seth S. , Cline Hollis T.
Published: January 2023

Protein degradation is critical for brain function through processes that remain incompletely understood. Here, we investigated the in vivo function of the 20S neuronal membrane proteasome (NMP) in the brain of
Xenopus laevis
tadpoles. With biochemistry, immunohistochemistry, and electron microscopy, we demonstrated that NMPs are conserved in the tadpole brain and preferentially degrade neuronal activity–induced newly synthesized proteins in vivo. Using in vivo calcium imaging in the optic tectum, we showed that acute NMP inhibition rapidly increased spontaneous neuronal activity, resulting in hypersynchronization across tectal neurons. At the circuit level, inhibiting NMPs abolished learning-dependent improvement in visuomotor behavior in live animals and caused a significant deterioration in basal behavioral performance following visual training with enhanced visual experience. Our data provide in vivo characterization of NMP functions in the vertebrate nervous system and suggest that NMP-mediated degradation of activity-induced nascent proteins may serve as a homeostatic modulatory mechanism in neurons that is critical for regulating neuronal activity and experience-dependent circuit plasticity.
Managers’ displays of busyness predict employees’ job engagement, burnout and turnover intentions (Las muestras de laboriosidad de los superiores predicen el compromiso laboral, el agotamiento y las intenciones de rotación del personal)
Authors: Park Lora E. , Italiano Alessia , Vessels Valerie
Published: January 2023

Although past research has examined the personal impact of experiencing time scarcity, little is known about how signalling a lack of time affects other people’s experiences. In the present research, we examine how managers’ displays of busyness — behaviours that convey time scarcity to others — affect employees’ job-related outcomes. Managers who frequently displayed busyness in the workplace had employees who perceived lower organizational support, which predicted lower job engagement, greater job burnout and intentions to leave the organization (Study 1). Even managers’ occasional displays of busyness negatively affected employees’ job-related experiences (Study 2). Furthermore, employees with managers who frequently displayed busyness reported worse job-related outcomes when the workplace was described as functional (vs. dysfunctional) (Study 3). Together, these findings suggest that frequent and even occasional displays of managers’ busyness predict lower employee engagement, greater job burnout and desire to leave the organization, especially in highly functional work environments.
Voltage-controlled bimeron diode-like effect in nanoscale information channel
Authors: Hu Gengxin , Luo Jia , Wang Junlin , Lu Xianyang , Zhao Guoping , Liu Yuan , Wu Jing , Xu Yongbing
Published: January 2023

The magnetic bimeron, as the in-plane counterpart of the magnetic skyrmion, has potential applications in next-generation spin memory devices due to its lower energy consumption. In this work, the dynamic behavior of a current-driven bimeron in a nanotrack with voltage-controlled magnetic anisotropy (VCMA) is investigated. By adjusting the profile of the VCMA, the bimeron can display a diode-like unidirectional behavior in the nanotrack. The unidirectional behavior can be modulated by changing the driven current density and width of the VCMA region. The trajectory of the bimeron can also be controlled by the periodic VCMA region, which can enhance the stability of bimeron and realize a high-storage density bimeron-based information channel.
Characterization of single-mode multimode single-mode fiber optic sensors for steel rebar corrosion monitoring in NaCl and simulated concrete pore solutions
Authors: Tang Fujian , Qin Jiangwei , Verstrynge Els , Dang Ji , Li Hong-Nan
Published: January 2023

Single-mode multimode single-mode (SMS) fiber optic sensors are characterized for corrosion monitoring of steel rebars in NaCl and simulated concrete pore solutions. Three diameters of the multimode fiber (MMF) are considered including 125 µm, 90 µm, and 60 µm. Steel rebar specimens were first cast in epoxy resin and then polished to expose a rectangular section. The SMS fiber optic sensors are directly attached on the polished surface of the steel rebar and then immersed in solutions for corrosion monitoring. Two types of solution are prepared, including 3.5 wt.% NaCl solution and simulated concrete pore solutions. During the immersion tests, the corrosion evolution of the steel rebar was measured with open circuit potential and linear polarization resistance. The change of the transmission spectrum of the SMS fiber optic sensors is recorded with an optical spectra analyzer. The change of the characteristic wavelength is correlated with the corrosion-induced mass loss of the steel rebars. Results show that linear relationships are present between the corrosion-induced mass loss of the steel rebars and the shift of the characteristic wavelength of the SMS fiber optic sensors. The corrosion monitoring sensitivity of SMS fiber optic sensors increases with a decrease of the diameter of the MMF.
Automated detection of schizophrenia using deep learning: a review for the last decade
Authors: Sharma Manish , Patel Ruchit Kumar , Garg Akshat , SanTan Ru , Acharya U Rajendra
Published: January 2023

Schizophrenia (SZ) is a devastating mental disorder that disrupts higher brain functions like thought, perception, etc., with a profound impact on the individual’s life. Deep learning (DL) can detect SZ automatically by learning signal data characteristics hierarchically without the need for feature engineering associated with traditional machine learning. We performed a systematic review of DL models for SZ detection. Various deep models like long short-term memory, convolution neural networks, AlexNet, etc., and composite methods have been published based on electroencephalographic signals, and structural and/or functional magnetic resonance imaging acquired from SZ patients and healthy patients control subjects in diverse public and private datasets. The studies, the study datasets, and model methodologies are reported in detail. In addition, the challenges of DL models for SZ diagnosis and future works are discussed.
Distributed thermometry for superconducting magnets using non-leaky acoustic waveguides
Authors: Marchevsky M , Prestemon S
Published: January 2023

Distributed temperature sensing is the preferred approach for detecting and localizing normal zones in the high-field magnets of particle accelerators and fusion energy systems based on high-temperature superconductors. Optical fibers show promise in realizing this approach but suffer from known drawbacks, such as fiber fragility and cross-sensitivity to strain. Guided acoustic wave-based thermometry is a viable alternative to fiber optics; however, its application is currently limited by the leaky nature of wave propagation in acoustic waveguides. We propose the novel concept of a cladded acoustic waveguide in which, due to the elimination of the adhesion between the core and cladding, propagation of longitudinal acoustic excitations is sustained over long distances without leaking wave energy to the environment. These acoustic fibers can be structurally integrated into superconducting magnets and enable the distributed detection of local heating via thermally driven variations in the sound velocity. We present the practical design of acoustic fibers and the results of the experimental detection and localization of heat sources using our technique under ambient and cryogenic conditions. The prospects of using this technique for superconducting magnet quench diagnostics are discussed.
Optimal design of broadband acoustic metasurface absorbers
Authors: Chen Yinghang , Xu Chi , Chen Jian , Li Zhi-Han , Chen Longhu , Huang Weichun , Lu Ming-Hui
Published: January 2023

The absorption of low-frequency noise has always been limited by structural thickness, but the novel physical properties of sound-absorbing metamaterials provide a solution to this problem. Based on genetic algorithm, an acoustic metasurface absorber (AMA) composed of micro-perforated plates (MPPs) and impedance matching coiled-up cavities (IMCCs) is proposed. Different from previously reported metamaterials, this structure can easily provide flexible and accurate broadband sound absorption in different target frequency bands. The theoretical model behind the algorithm is established, and two optimal structures (AMA I/AMA II) are obtained for low and mid-high frequency bands. Broadband sound absorption is realized with a thickness of only 71 mm (about 1/13 of the relevant wavelength at 369 Hz), and an average sound absorption coefficient of 0.931 is achieved in the low-frequency band of 350–1000 Hz. Furthermore, by changing the frequency band of the quasi-perfect absorber to 500–2000 Hz, the average sound absorption coefficient exceeds 0.945 with a thickness of only 55 mm (about 1/11 of the relevant wavelength at 563 Hz). The reflection coefficient in the complex plane and theoretical impedance analysis are utilized to reveal the underlying mechanism of the absorption and the acoustic characteristics of the two structures, which show excellent broadband absorption performance in the low and mid-high frequency bands. This work provides a method of arbitrarily modulating surface acoustic impedance in broadband and a reference for broadband noise control.
Nonclassicality of dissipative cavity optomagnonics in the presence of Kerr nonlinearities
Authors: Moslehi Mahboobeh , Baghshahi Hamid Reza , Faghihi Mohammad Javad , Mirafzali Sayyed Yahya
Published: January 2023

The phenomena of photon and magnon blockade, and nonclassicality which are the key ingredient for quantum enhanced technologies, can be considered as resources in quantum information processing. This paper deals with the study of nonclassicality in a lossy optomagnonic microcavity enclosed by Kerr medium, with considering different sources of dissipation. The system contains a ferromagnetic YIG sphere coupled to two optical modes in a microcavity, with photonic and magnonic Kerr nonlinearity in the presence of magnonic and photonic losses. Considering the Heisenberg-Langevin approach, we obtain the dynamics of the second-order correlation functions (CFs) to observe the phenomenon of photon and magnon blockade (PMB), and the Cauchy-Schwarz inequality (CSI) to find the nonclassicality of the system. We then discuss the effects of magnon-photon coupling strength and different sources of dissipation on the temporal behavior of the mentioned criteria. Looking at the numerical results, we find that the depth and the domain of antibunching behavior significantly depend on the value of the thermal average photon (magnon) number. The phenomenon of perfect PMB may also be observed in the presence of dissipation at the low-temperature regime where the equilibrium thermal photon (magnon) occupation number approaches zero, i.e. T → 0. Moreover, we see a strong anticorrelation between the photonic and magnonic modes and the optical modes, too. Furthermore, it can be found that the phenomenon of PMB blockade as well as antibunching can be observed at cryogenic temperatures.
Top-quark pair production by electron–positron annihilation in a circularly polarized laser field
Authors: Chahri R , Mouslih S , Jakha M , Manaut B , Taj S
Published: January 2023

In the framework of the electroweak standard model, we have investigated the top quarks pair production from

e

−

e

+

annihilation at the energies of a future compact linear collider in the presence of an intense circularly polarized laser field. We have analytically generated the detailed expression for the laser-assisted differential cross section using the lowest-order Dirac-Volkov formalism, including the

γ
t

t
ˉ

and

Z
t

t
ˉ

interactions, in the center-of-mass frame. A wide range of center-of-mass energies corresponding to the future

e

−

e

+

collider has been covered to study the behavior of the total cross section (TCS); this future compact linear collider constitutes an important direction in the study of top quark physics in order to improve the measurements, and the limits of some physical parameters obtained so far at the LHC and the Tevatron. We have analyzed the dependence of the laser-assisted total and partial cross sections on the energy of the center-of-mass of the colliding system

e

−

e

+

and also on the parameters of the laser field, such as the number of exchanged photons, the laser field strength, and its frequency. The results indicate that the laser field decreases the order of magnitude of the TCS as much as the laser field strength increases or decreases its frequency.
Hybrid-kinetic simulation of synergy between fishbone/sawtooth and tearing mode-induced energetic-ion transport in a tokamak plasma
Authors: Zhu X.L. , Yu L.M. , Chen W. , Shi P.W. , Ge W.L. , Wang F. , Luan Q.B. , Sun H.E. , Wang Z.X.
Published: January 2023

The resonant interaction between

m

/

n
=
2

/

1

tearing mode (TM) and energetic ions redistributed by

m

/

n
=
1

/

1

fishbone/sawtooth collapse has been observed recently in HL-2A neutral beam injection-heated high-density plasmas, where m is the poloidal mode number and n is the toroidal mode number. This event essentially results from a synergistic effect with a multiple-mode nature. Understanding such experimental phenomena, especially when using high-power auxiliary heating, is crucial for achieving high-performance plasmas with high confinement and high β

N
in the prospective thermonuclear fusion reactors. In this work, based on the typical experimental phenomenon of synergy between fishbone/sawtooth and TM on HL-2A, a self-consistent nonlinear hybrid-kinetic simulation is conducted utilizing the experimental parameters and profiles before the occurrence of this synergy as the code M3D-K input. In particular, we focus chiefly on the phase-space transport, loss and redistribution of energetic ions induced by two cases, one with only

m

/

n
=
2

/

1

TM and one with synergy between

m

/

n
=
1

/

1

fishbone/sawtooth and

m

/

n
=
2

/

1

TM. It is found that the synergy of the fishbone/sawtooth and

m

/

n
=
2

/

1

TM on energetic-ion transport, loss and redistribution is important and can dramatically enhance the loss rate of energetic ions compared with the case with only

m

/

n
=
2

/

1

TM. It is due to the fact that such synergy can open up an efficient energetic-ion loss channel which connects the plasma center and edge. The phase space transport and redistribution of energetic ions induced by the two different cases are also respectively analyzed and compared in detail. Because of the overestimation of amplitudes of fishbone/sawtooth and TM in the simulations, the obtained energetic-ion transport level is only limited in the context of the numerical framework. These findings indicate that the synergy triggering the sawtooth collapse may lead to an enhancement of the energetic-ion transport and can help us understand the underlying mechanisms of synergy-induced energetic-ion transport.
Changing PM2.5 and related meteorology over India from 1950–2014: a new perspective from a chemistry-climate model ensemble
Authors: Hancock Sarah , Fiore Arlene M , Westervelt Daniel M , Correa Gus , Lamarque Jean-François , Venkataraman Chandra , Sharma Arushi
Published: January 2023

Surface PM2.5 concentrations in India have increased dramatically as emissions have risen in recent years. The role of meteorological factors in this increase is unclear, mainly due to a lack of long-term observations over the region. A 12-member ensemble of historical (1950–2014) simulations from the Community Earth System Model version 2-Whole Atmosphere Community Climate Model version 6 (CESM2-WACCM6) offers an unprecedented opportunity to examine simulated PM2.5 and meteorology for 20th century climates that can arise due to ‘climate noise’ under the same historical greenhouse gas and air pollutant emission trajectories. CESM2-WACCM6 includes interactive aerosol and gas-phase chemistry in the atmosphere coupled to ocean-sea ice-land models, and each ensemble member differs only in its initial conditions of the climate state. We systematically examine, decade-by-decade, the changes in PM2.5 and associated meteorology, including wind speed, surface temperature inversions, boundary layer height, precipitation, and relative humidity in four cities in India: Chennai, Kolkata, Mumbai, and New Delhi. Forced changes clearly emerge in meteorological variables from 1950 to 2014, including increases in both relative humidity and temperature inversion strength, and decreases in boundary layer height and average surface wind speed. The timing of these changes varies by city: boundary layer heights decrease most over New Delhi in the premonsoon season (ensemble average decrease of 400 m), but over Mumbai in the postmonsoon season (ensemble average decrease of 100 m). PM2.5 concentrations increase across India regardless of climate variability, with an almost threefold increase from 1950 to 2014 over New Delhi. Analysis of dimensionless variables shows that PM2.5 exhibits larger ensemble mean trends and smaller variability than the trends in the meteorological variables, enabling us to infer that the increase in PM2.5 is predominantly controlled by increases in anthropogenic emissions rather than climate variability. Overall, our simulations corroborate the dominant role of air pollutant emissions on poor air quality in India.
A deterministic counterexample for high dimensional 𝐿²𝐿^{∞} Strichartz estimates for the Wave equation
Authors: Gavrus Cristian
Published: January 2023

In this note we discuss the question of homogeneous

L
2

L

∞

L^2 L^{\infty }

Strichartz estimates for the Wave equation in dimensions

n
≥
4

n \geq 4

raised by Fang and Wang and recently shown to fail by Guo, Li, Nakanishi and Yan using probability theory. We record a deterministic example for disproving this estimate.
On the Liouville property for fully nonlinear equations with superlinear first-order terms
Authors: Cirant Marco , Goffi Alessandro
Published: January 2023

We consider in this note one-side Liouville properties for viscosity solutions of various fully nonlinear uniformly elliptic inequalities, whose prototype is

F
(
x
,

D
2

u
)
≥

H
i

(
x
,
u
,
D
u
)

F(x,D^2u)\geq H_i(x,u,Du)

in

R

N

\mathbb {R}^N

, where

H
i

H_i

has superlinear growth in the gradient variable. After a brief survey on the existing literature, we discuss the validity or the failure of the Liouville property in the model cases

H
1

(
u
,
D
u
)
=

u
q

+

|

D
u

|

γ

H_1(u,Du)=u^q+|Du|^\gamma

,

H
2

(
u
,
D
u
)
=

u
q

|

D
u

|

γ

H_2(u,Du)=u^q|Du|^\gamma

and
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper H 3 left-parenthesis x comma u comma upper D u right-parenthesis equals plus-or-minus u Superscript q Baseline StartAbsoluteValue upper D u EndAbsoluteValue Superscript gamma Baseline minus b left-parenthesis x right-parenthesis dot upper D u">

H
3

(
x
,
u
,
D
u
)
=
±

u
q

|

D
u

|

γ

−
b
(
x
)
⋅
D
u

H_3(x,u,Du)=\pm u^q|Du|^\gamma -b(x)\cdot Du

, where

q
≥
0

q\geq 0

,

γ
>
1

\gamma >1

and

b
b

is a suitable velocity field. Several counterexamples and open problems are thoroughly discussed.
A rank-two relaxed parallel splitting version of the augmented Lagrangian method with step size in (0,2) for separable convex programming
Authors: He Bingsheng , Ma Feng , Xu Shengjie , Yuan Xiaoming
Published: January 2023

The augmented Lagrangian method (ALM) is classic for canonical convex programming problems with linear constraints, and it finds many applications in various scientific computing areas. A major advantage of the ALM is that the step for updating the dual variable can be further relaxed with a step size in

(
0
,
2
)

(0,2)

, and this advantage can easily lead to numerical acceleration for the ALM. When a separable convex programming problem is discussed and a corresponding splitting version of the classic ALM is considered, convergence may not be guaranteed and thus it is seemingly impossible that a step size in

(
0
,
2
)

(0,2)

can be carried on to the relaxation step for updating the dual variable. We show that for a parallel splitting version of the ALM, a step size in

(
0
,
2
)

(0,2)

can be maintained for further relaxing both the primal and dual variables if the relaxation step is simply corrected by a rank-two matrix. Hence, a rank-two relaxed parallel splitting version of the ALM with a step size in

(
0
,
2
)

(0,2)

is proposed for separable convex programming problems. We validate that the new algorithm can numerically outperform existing algorithms of the same kind significantly by testing some applications.
World Health Organization strategic framework for integrated control and management of skin-related neglected tropical diseases: what does this mean for dermatologists?
Authors: Yotsu Rie R , Fuller L Claire , Murdoch Michele E , Revankar Chandrakant , Barogui Yves Thierry , Pemmaraju Venkata Ranganandha Rao , Ruiz-Postigo Jose-Antonio , Dagne Daniel Argaw , Asiedu Kingsley , Hay Roderick J
Published: January 2023

Skin-related neglected tropical diseases, or skin NTDs, comprise a group of NTDs that produce signs and symptoms on the skin, and includes at least nine diseases and disease groups. The World Health Organization launched the ‘Ending the neglect to attain the Sustainable Development Goals: a strategic framework for integrated control and management of skin-related neglected tropical diseases’ in June 2022, which this article summarises and sets out the way forward including guidance on how dermatologists and dermatological communities along with public health communities may support this initiative to contribute towards achieving skin care for everyone everywhere.
Folliculin inactivation and cutaneous leiomyosarcoma in Birt-Hogg-Dubé syndrome
Authors: Fostier William , Holt Georgie , Sampson James , Rajan Neil
Published: January 2023

Cutaneous leiomyosarcoma (cLMS) is a rare soft tissue sarcoma where the genetic drivers implicated in carcinogenesis are not completely characterized despite extensive genomic profiling. The presentation of cLMS in Birt-Hogg-Dube (BHD) syndrome, which is caused by heterozygous pathogenic variants in FLCN, adds to our mechanistic understanding of the pathogenesis of cLMS and implicates FLCN loss. In this report, we demonstrate loss of heterozygosity (LOH) of FLCN in BHD cLMS, providing novel genetic evidence that a subset of cLMS may be driven by FLCN loss and that cLMS is an infrequent but recurrent element of the BHD phenotype.
Dermoscopy of subclinical nail involvement in patients with diabetes mellitus: a case–control study
Authors: Hofny Eman R M , Tawfik Yasmin M , Hasan Mohamed S , Salah Yasmin , Rageh Mahmoud A
Published: January 2023

Background

Diabetes mellitus (DM) is a chronic disease characterized by elevated blood glucose levels that can lead to serious complications. Nails are a mirror for general health so changes in nails can be an indicator of disease progression in patients with DM.

Aim

To detect subclinical nail changes in patients with DM using dermoscopy.

Methods

In total, 100 participants were recruited, all of them from outpatient clinics, made up of a group with DM (n = 50) and an age- and sex-matched control group without DM (n = 50). All patients had clinically apparently normal nails. In both groups, dermoscopic examinations were conducted and compared.

Results

It was found that 33 patients in the DM group (66%) had dermoscopic nail findings in the form of microhaemorrhage (26%), longitudinal striations (24%), distal subungual onychomycosis (24%), superficial pitting (20%), distal onycholysis (18%), splinter haemorrhage (14%), subungual hyperkeratosis (12%), dilated vessels (10%) and distal yellowish discoloration (8%).

Conclusion

Nail examination can be accomplished with the help of dermoscopy to detect subclinical nail changes in patients diagnosed with DM and, therefore, can give us an idea about disease progression and help with control of DM and treatment plans.
The RNA-binding protein QKI governs a muscle-specific alternative splicing program that shapes the contractile function of cardiomyocytes
Authors: Montañés-Agudo Pablo , Aufiero Simona , Schepers Eva N , van der Made Ingeborg , Cócera-Ortega Lucia , Ernault Auriane C , Richard Stéphane , Kuster Diederik W D , Christoffels Vincent M , Pinto Yigal M , Creemers Esther E
Published: January 2023

Aims

In the heart, splicing factors orchestrate the functional properties of cardiomyocytes by regulating the alternative splicing of multiple genes. Work in embryonic stem cells has shown that the splicing factor Quaking (QKI) regulates alternative splicing during cardiomyocyte differentiation. However, the relevance and function of QKI in adult cardiomyocytes remains unknown. In this study, we aim to identify the in vivo function of QKI in the adult mouse heart.

Methods and results

We generated mice with conditional deletion of QKI in cardiomyocytes by the Cre-Lox system. Mice with cardiomyocyte-specific deletion of QKI died during the foetal period (E14.5), without obvious anatomical abnormalities of the heart. Adult mice with tamoxifen-inducible QKI deletion rapidly developed heart failure associated with severe disruption of sarcomeres, already 7 days after knocking out QKI. RNA sequencing revealed that QKI regulates the alternative splicing of more than 1000 genes, including sarcomere and cytoskeletal components, calcium-handling genes, and (post-)transcriptional regulators. Many of these splicing changes corresponded to the loss of muscle-specific isoforms in the heart. Forced overexpression of QKI in cultured neonatal rat ventricular myocytes directed these splicing events in the opposite direction and enhanced contractility of cardiomyocytes.

Conclusion

Altogether, our findings show that QKI is an important regulator of the muscle-specific alternative splicing program that builds the contractile apparatus of cardiomyocytes.
Empagliflozin inhibits excessive autophagy through the AMPK/GSK3β signalling pathway in diabetic cardiomyopathy
Authors: Madonna Rosalinda , Moscato Stefania , Cufaro Maria Concetta , Pieragostino Damiana , Mattii Letizia , Del Boccio Piero , Ghelardoni Sandra , Zucchi Riccardo , De Caterina Raffaele
Published: January 2023

Aims

Sodium-glucose cotransporter 2 inhibitors have beneficial effects on heart failure and cardiovascular mortality in diabetic and non-diabetic patients, with unclear mechanisms. Autophagy is a cardioprotective mechanism under acute stress conditions, but excessive autophagy accelerates myocardial cell death leading to autosis. We evaluated the protective role of empagliflozin (EMPA) against cardiac injury in murine diabetic cardiomyopathy.

Methods and results

Male mice, rendered diabetics by one single intraperitoneal injection of streptozotocin and treated with EMPA (30 mg/kg/day), had fewer apoptotic cells (4.9 ± 2.1 vs. 1 ± 0.5 TUNEL-positive cells %, P < 0.05), less senescence (10.1 ± 2 vs. 7.9 ± 1.2 β-gal positivity/tissue area, P < 0.05), fibrosis (0.2 ± 0.05 vs. 0.15 ± 0.06, P < 0.05 fibrotic area/tissue area), autophagy (7.9 ± 0.05 vs. 2.3 ± 0.6 fluorescence intensity/total area, P < 0.01), and connexin (Cx)-43 lateralization compared with diabetic mice. Proteomic analysis showed a down-regulation of the 5′ adenosine monophosphate-activated protein kinase (AMPK) pathway and upstream activation of sirtuins in the heart of diabetic mice treated with EMPA compared with diabetic mice. Because sirtuin activation leads to the modulation of cardiomyogenic transcription factors, we analysed the DNA binding activity to serum response elements (SRE) of serum response factor (SRF) by electromobility shift assay. Compared with diabetic mice [0.5 ± 0.01 densitometric units (DU)], non-diabetic mice treated with EMPA (2.2 ± 0.01 DU, P < 0.01) and diabetic mice treated with EMPA (2.0 ± 0.1 DU, P < 0.01) significantly increased SRF binding activity to SRE, paralleled by increased cardiac actin expression (4.1 ± 0.1 vs. 2.2 ± 0.01 target protein/β-actin ratio, P < 0.01). EMPA significantly reversed cardiac dysfunction on echocardiography in diabetic mice and inhibited excessive autophagy in high-glucose-treated cardiomyocytes by inhibiting the autophagy inducer glycogen synthase kinase 3 beta (GSK3β), leading to reactivation of cardiomyogenic transcription factors.

Conclusion

Taken together, our results describe a novel paradigm in which EMPA inhibits hyperactivation of autophagy through the AMPK/GSK3β signalling pathway in the context of diabetes.
Cardiac manifestations and clinical management of X-linked Emery-Dreifuss muscular dystrophy: a case series
Authors: Kashyap Niharika , Nikhanj Anish , Gagnon Luke R , Moukaskas Basel , Siddiqi Zaeem A , Oudit Gavin Y
Published: January 2023

Background

Heart disease is an under-recognized cause of morbidity and mortality in patients with Emery-Dreifuss muscular dystrophy (EDMD). Arrhythmias and conduction delays are highly prevalent and given the rarity of this disease the patient care process remains poorly defined.

Case summary

This study closely followed four adult patients from the Neuromuscular Multidisciplinary Clinic (Alberta, Canada) that presented with X-linked recessive EDMD. Patients were assessed and managed on a case-by-case basis. Clinical status and cardiac function were assessed through clinical history, physical examination, and investigations (12-lead electrocardiogram, 24 hour Holter monitor, transthoracic echocardiogram, and plasma biomarkers). Conduction disease, requiring permanent pacemaker, was prevalent in all patients. With appropriate medical therapy over a median follow-up period five years the cardiac status was shown to have stabilized in all these patients.

Discussion

We demonstrate the presentation of arrhythmias, conduction abnormalities, and chamber dilation in adult patients with X-linked EDMD. Cardiac medications and pacemaker therapy are shown to prevent adverse outcomes from these complications. Patients with EDMD are expected to develop heart disease early and prior to the development of an overt neuromuscular phenotype. These patients should be closely monitored in a multidisciplinary setting for effective management to improve their clinical outcomes.
Coronary subclavian steal syndrome due to thrombosis of the left subclavian artery aneurysm: a case report
Authors: Kiugel Max , Dabravolskaite Vaiva , Paana Tuomas , Helmiö Päivi
Published: January 2023

Background

Coronary subclavian steal syndrome (CSSS) is an often easily overlooked cause of angina that may occur after a coronary artery bypass graft (CABG) procedure. The onset of CSSS several years after coronary revascularization has been described in case reports, and in the few retrospective reviews that compare the endovascular approach with surgical treatment. Subclavian stenosis can naturally coincide with coronary artery disease and may already be present during the initial CABG.

Case summary

A 59-year-old male with a history of three-vessel disease who had a left internal mammary artery (LIMA) bypass graft, exhibited a gradual worsening of angina that coincided with numbness and impaired function of the left fingers, hand, and arm. Myocardial perfusion imaging showed reversible ischaemia, and coronary angiography suggested a thrombotic lesion proximal to the LIMA ostium. Calcified and partially thrombosed proximal left subclavian artery (LSA) aneurysm was visualized using computed tomography imaging, whereas Doppler ultrasound revealed a partially reversed vertebral flow. The lowest risk treatment was a bypass between the left common carotid artery and the LSA. The procedure was immediately successful, with cessation of symptoms and a favourable medium-term outcome.

Discussion

As no guidelines exist for such cases, the importance of multidisciplinary co-operation in diagnostics and devising a treatment plan is underlined. Moreover, screening for subclavian artery stenosis in CABG candidates should be warranted as part of the initial preoperative assessment.