bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trapping of H2− in aluminum hydride, Al4H14−
Authors: Kiran Boggavarapu , Bowen Kit H. , Kandalam Anil K. 
Published: September 2021

Ever since our first experimental and computational identification of Al4H6 as a boron analog [X. Li et al., Science 315, 356 (2007)], studies on aluminum hydrides unveiled a richer pattern of structural motifs. These include aluminum-rich hydrides, which follow shell closing electron counting models; stoichiometric clusters (called baby crystals), which structurally correspond to the bulk alane; and more. In this regard, a mass spectral identification of unusually high intense peak of Al4H14−, which has two hydrogen atoms beyond stoichiometry, has remained mostly unresolved [X. Li et al., J. Chem. Phys. 132, 241103 (2010)]. In this Communication, with the help of global minima methods and density functional theory-based calculations, we identify the lowest energy bound structure with a unique Al–H–H–Al bonding. Our electronic structural analysis reveals that two Al2H6 units trap a transient, metastable H2−. In other words, three stable molecules, two Al2H6 and an H2, are held together by a single electron. Our studies provide a pathway to stabilize transient species by making them part of a more extensive system.
Metabolism modulates network synchrony in the aging brain
Authors: Weistuch Corey , Mujica-Parodi Lilianne R. , Razban Rostam M. , Antal Botond , van Nieuwenhuizen Helena , Amgalan Anar , Dill Ken A. 
Published: September 2021

Significance
How do brains adapt to changing resource constraints? This is particularly relevant in the aging brain, for which the ability of neurons to utilize their primary energy source, glucose, is diminished. Through experiments and modeling, we find that changes to brain activity patterns with age can be understood in terms of decreasing metabolic activity. Specifically, we find that older brains approach a critical point in our model, enabling small changes in metabolic activity to give rise to an abrupt reconfiguration of functional brain networks.
Activity waves and freestanding vortices in populations of subcritical Quincke rollers
Authors: Liu Zeng Tao , Shi Yan , Zhao Yongfeng , Chaté Hugues , Shi Xia-qing , Zhang Tian Hui 
Published: September 2021

Significance
Active matter is made of units that move or displace others by using energy stored internally or gathered from their environment. In most systems and models considered so far, these self-propelled units are constantly moving. Here we study active matter made of units that do not move when isolated, but can be set into motion by close neighbors. Our subcritical active matter consists of Quincke rollers, that is, colloidal spheres at the bottom of a cell filled with conducting fluid submitted to a vertical electric field. We find spectacular collective self-organized phenomena: activity waves propagating in a quiescent population, and arbitrarily large, steadily rotating vortices forming without confinement or particle chirality.
Matrix stiffness drives stromal autophagy and promotes formation of a protumorigenic niche
Authors: Hupfer Anna , Brichkina Anna , Koeniger Anke , Keber Corinna , Denkert Carsten , Pfefferle Petra , Helmprobst Frederik , Pagenstecher Axel , Visekruna Alexander , Lauth Matthias 
Published: September 2021

Significance
Increased tissue stiffness is a hallmark of several diseases such as organ fibrosis or cancer, and tissue fibroblasts play central roles in these pathologies. In tumors, stromal cells support the growth of cancer cells by supplying signaling molecules and nutrients, the latter also being provided by stromal autophagy. The mechanisms inducing these processes are, however, not well understood. Here, we demonstrate that an increased physical rigidity of a fibroblast’s environment is sufficient to evoke stromal autophagy. Mechanistically, matrix stiffness is transmitted via Integrin αV receptors and focal adhesion kinase, resulting in stabilization of AMPK at focal adhesion structures. Stiffness-mediated stromal autophagy supports the growth of neighboring tumor cells in vitro and in vivo, opening possibilities for anti-cancer therapies.
Mechanistic insights into central spindle assembly mediated by the centralspindlin complex
Authors: Pan Han , Guan Ruifang , Zhao Ruixue , Ou Guangshuo , Chen Zhucheng 
Published: September 2021

Significance
Centralspindlin bundles microtubules to assemble the central spindle, being essential for cytokinesis of the cell. It is a heterotetramer formed by ZEN-4 and CYK-4 in a 2:2 manner. We determined the crystal structures of centralspindlin, which revealed the detailed mechanism of complex formation. We found that centralspindlin clustered to undergo liquid–liquid phase separation (LLPS), which depended on the complementary charged residues located at ZEN-4 and CYK-4, respectively, explaining the synergy of the two subunits for the function. The LLPS of centralspindlin is critical for the microtubule bundling activity in vitro and the assembly of the central spindle in vivo. Together, our study provides angstrom-to-micron mechanistic insights into central spindle assembly mediated by the centralspindlin complex.
Interpreting in Tanzania from the perspective of Tanzanian interpreters
Authors: Getta Elizaveta 
Published: September 2021

Abstract
The study overviews the role of interpreting services in Tanzania, presenting mainly the experience of practicing freelance interpreters. The two official languages of Tanzania – English and Swahili – have separate roles in the country. Although most Tanzanians accept English as a necessary medium of intercultural communication, Swahili is perceived as an important part of Tanzanian national identity. It is the country’s lingua franca. On the one hand, Tanzania aims to preserve communication in Swahili; on the other hand, there is an inevitable need for intercultural communication with the rest of the world that grows especially in the context of globalization. The paper focuses on the role, status, education, working languages, conditions of Tanzanian interpreters, and the requirements of local and international clients. The study also creates a broader context that mentions crucial historical moments that have influenced the country’s current character of intercultural communication.
Britain as a protector, a mediator or an onlooker?
Authors: Wang Guofeng 
Published: September 2021

AbstractSince Hong Kong’s handover to China, British newspapers still play an active role in constructing Britain’s connections with its former colony. This study elaborates a schema for protests to help better understand protests in general. Based on this schema, the study examined representations of the 2019–20 protests in British newspapers using the approach of corpus-assisted critical discourse studies. The analysis shows that they mainly used the predicational strategy, and emphasized the Chinese government’s control of Hong Kong – including the inabilities of the Hong Kong government and police violence – in contrast with the protestors’ demands for universal suffrage. They suggested that Britain act as a mediator to shoulder a moral responsibility over Hong Kong. Their attitudes are interpreted with regard to Britain’s foreign policies and the dominant ideology cultivated in its historical, socio-political contexts and suggest that the UK journalistic practice regarding Hong Kong issues is political-driven to a great extent.
Surface and underground seismic characterization at Terziet in Limburg—the Euregio Meuse–Rhine candidate site for Einstein Telescope
Authors: Koley Soumen , Bader Maria , van den Brand Jo , Campman Xander , Bulten Henk Jan , Linde Frank , Vink Bjorn 
Published: September 2021

Abstract
We present a detailed characterization of surface and underground seismic noise measured at Limburg in the south of the Netherlands. This location is the Euregio Meuse–Rhine candidate for hosting Einstein Telescope, a future observatory for gravitational waves. Seismic noise measurements were performed with an array of seismometers installed on the surface. Passive seismic methods like beamforming were used to extract the propagation wave types of ambient seismic noise and the Rayleigh-wave dispersion in the region. Subsurface shear-wave models sensitive to depths of 300 m were derived by using the Rayleigh-wave dispersion and ellipticity. Subsurface P-wave velocities to depths of 200 m were obtained from an active seismic survey. Wavepath Eikonal tomography was used on the source-receiver refracted-wave travel-times to obtain a subsurface P-wave velocity model. Both the passive and the active seismic data analysis point to the presence of a layered geology with a soft-soil to hard-rock transition occurring at a shallow depth of about 25 to 40 m. The surface arrays are complemented by two permanent tri-axial seismometers installed on the surface and in a borehole at 250 m depth. Their data are used to interpret the surface-wave and body-wave contributions to the observed seismic noise. We use a cross-correlation analysis and compute the theoretical surface-wave eigenfunctions to understand the contributions of the different wave types at different frequencies. We observe that below 4 Hz in the horizontal component and 9 Hz in the vertical component, the seismic noise at depth is dominantly due to surface waves. Above these frequencies a significant contribution can be attributed to both nearby and far-away body-wave sources. At a depth of 250 m we find that the surface noise power has been damped by up to a factor 104 above about 2 Hz. The Limburg geology with soft-soil on top of hard-rock efficiently damps the anthropogenic noise produced at the surface. This implies that Einstein Telescope’s test masses are shielded from anthropogenic seismic noise and construction at greater depth will not bring significant further improvements in this regard. A body-wave background has been identified that contributes about half of the total underground seismic noise at 250 m depth for frequencies above 4 Hz. It remains to be studied if subtraction schemes for Newtonian noise originating from this body-wave background will be necessary. Finally, we estimate an interferometer downtime of about 3% due to regional and teleseismic earthquakes. We believe this is acceptable as it is comparable to current experience at the LIGO and Virgo interferometer sites.
Adaptive polygon rendering for interactive visualization in the Schwarzschild spacetime
Authors: Müller Thomas , Schulz Christoph , Weiskopf Daniel 
Published: September 2021

Abstract
Interactive visualization is a valuable tool for introductory or advanced courses in general relativity as well as for public outreach to provide a deeper understanding of the visual implications due to curved spacetime. In particular, the extreme case of a black hole where the curvature becomes so strong that even light cannot escape, benefits from an interactive visualization where students can investigate the distortion effects by moving objects around. However, the most commonly used technique of four-dimensional general-relativistic ray tracing is still too slow for interactive frame rates. Therefore, we propose an efficient and adaptive polygon rendering method that takes light deflection and light travel time into account. An additional advantage of this method is that it provides a natural demonstration of how multiple images occur and how light travel time affects them. Finally, we present our method using three example scenes: a triangle passing behind a black hole, a sphere orbiting a black hole and an accretion disk with different inclination angles.
Intercalated water mediated electromechanical response of graphene oxide films on flexible substrates
Authors: Devendar Lavudya , Shijeesh M R , Sakorikar Tushar , Ganapathi K Lakshmi , Jaiswal Manu 
Published: September 2021

Abstract
The confinement of water between sub-nanometer bounding walls of layered two-dimensional materials has generated tremendous interest. Here, we examined the influence of confined water on the mechanical and electromechanical response of graphene oxide films, prepared with variable oxidative states, casted on polydimethylsiloxane substrates. These films were subjected to uniaxial strain under controlled humid environments (5 to 90% RH), while dc transport studies were performed in tandem. Straining resulted in the formation of quasi-periodic linear crack arrays. The extent of water intercalation determined the density of cracks formed in the system thereby, governing the electrical conductance of the films under strain. The crack density at 5% strain, varied from 0 to 3.5 cracks mm−1 for hydrated films and 8 to 22 cracks mm−1 for dry films, across films with different high oxidative states. Correspondingly, the overall change in the electrical conductance at 5% strain was observed to be ∼5 to 20 folds for hydrated films and ∼20 to 35 folds for the dry films. The results were modeled with a decrease in the in-plane elastic modulus of the film upon water intercalation, which was attributed to the variation in the nature of hydrogen bonding network in graphene oxide lamellae.
vdW-DF-ahcx: a range-separated van der Waals density functional hybrid
Authors: Shukla Vivekanand , Jiao Yang , Frostenson Carl M , Hyldgaard Per 
Published: September 2021

Abstract
Hybrid density functionals replace a fraction of an underlying generalized-gradient approximation (GGA) exchange description with a Fock-exchange component. Range-separated hybrids (RSHs) also effectively screen the Fock-exchange component and thus open the door for characterizations of metals and adsorption at metal surfaces. The RSHs are traditionally based on a robust GGA, such as PBE (Perdew J P et al 1996 Phys. Rev. Lett.
77 3865), for example, as implemented in the HSE design (Heyd J et al 2003 J. Chem. Phys.
118 8207). Here we define an analytical-hole (Henderson T M et al 2008 J. Chem. Phys.
128 194105) consistent-exchange RSH extension to the van der Waals density functional (vdW-DF) method (Berland K et al 2015 Rep. Prog. Phys.
78 066501), launching vdW-DF-ahcx. We characterize the GGA-type exchange in the vdW-DF-cx version (Berland K and Hyldgaard P 2014 Phys. Rev. B
89 035412), isolate the short-ranged exchange component, and define the new vdW-DF hybrid. We find that the performance vdW-DF-ahcx compares favorably to (dispersion-corrected) HSE for descriptions of bulk (broad molecular) properties. We also find that it provides accurate descriptions of noble-metal surface properties, including CO adsorption.
Protected quantum coherence by gain and loss in a noisy quantum kicked rotor
Authors: Wang Wen-Yuan , Zhao Wen-Lei 
Published: September 2021

Abstract
We study the effects of non-Hermiticity on quantum coherence via a noisy quantum kicked rotor (NQKR). The random noise comes from the fluctuations in kick amplitude at each time. The non-Hermitian driving indicates the imaginary kicking potential, representing the environment-induced atom gain and loss. In the absence of gain and loss, the random noise destroys quantum coherence manifesting dynamical localization, which leads to classical diffusion. Interestingly, in the presence of non-Hermitian kicking potential, the occurrence of dynamical localization is highly sensitive to the gain and loss, manifesting the restoration of quantum coherence. Using the inverse participation ratio arguments, we numerically obtain a phase diagram of the classical diffusion and dynamical localization on the parameter plane of noise amplitude and non-Hermitian driving strength. With the help of analysis on the corresponding quasieigenstates, we achieve insight into dynamical localization, and uncover that the origin of the localization is interference between multiple quasi-eigenstates of the quantum kicked rotor. We further propose an experimental scheme to realize the NQKR in a dissipative cold atomic gas, which paves the way for future experimental investigation of an NQKR and its anomalous non-Hermitian properties.
Micromagnetic modeling of magnon coherent states in a nonuniform magnetic field
Authors: Belanovsky A D , Vetoshko P M , Bunkov Yu M 
Published: September 2021

Abstract
Quantum magnonics is an emerging research field, with great potential for applications in a magnon based quantum technologies, including quantum computing, processing and encoding information. Magnon correlation and quantum entanglement are the main concepts in many quantum technologies under development. Of particular interest is the magnon Bose condensation. The emerging current question is the applicability of quasi-classical Landau–Lifshitz–Gilbert equations to describe the coherent state of magnons. We performed micromagnetic modeling of the magnetization dynamics at a high angle of deviation in an inhomogeneous magnetic field. We have obtained solutions that are well coincided with the properties of experimentally observed magnon BEC states. This result will be needed for the calculation the properties of magnetic devices on the basis of quantum magnonics.
A fault diagnosis method for rolling bearings based on inter-class repulsive force discriminant transfer learning
Authors: Wang Teng , Li Tongyi , Jiang Peixuan , Cheng Yangyang , Tang Tuojiang 
Published: September 2021

Abstract
For fault diagnosis of rolling bearings, it is generally difficult or even impossible to obtain class labels of new working condition samples under actual variable working conditions, which leads to a low fault diagnosis accuracy. On account of this, we propose a novel unsupervised transfer learning method called inter-class repulsive force discriminant transfer learning (IRFDTL) in this paper. In the proposed IRFDTL, to reduce the classification error in source domain and improve the generalization ability of IRFDTL, a nonnegative extended slack matrix is creatively constructed to transform the strict binary label matrix into an extended slack label matrix. Moreover, the joint distribution discrepancy is introduced to reduce the difference between source and target domains, and the inter-class repulsive force term is innovatively designed to promote the discriminative learning effect by increasing the inter-class distance. Finally, the whole framework of IRFDTL is optimized by the alternating direction multiplier method. By using the labeled samples under historical working conditions, the IRFDTL can perform high-precision class discrimination on the testing samples under new working conditions when there are no class labels of testing samples. The proposed IRFDTL-based fault diagnosis method can achieve precise fault diagnosis of the testing samples under new working conditions, and fault diagnosis instances of rolling bearings verify the effectiveness of the proposed method.
Design of Menger sponge fractal structural NiTi as bone implants
Authors: Zhang Xudong , Yang Fan , Liu Baosheng , Deng Junkai 
Published: September 2021

Abstract
Finite element simulations were performed to investigate potential applications of Menger sponge fractal NiTi structures as bone implants. The tunable correlations between porosity and fractal parameters in Menger sponge fractal structures were explored to match the characteristics of the natural bones, including porosity, hierarchical porous structures, and fractal dimensions. The computational results demonstrate that the broad range of elastic modulus and yield stress in our designed fractal NiTi structures can satisfy the mechanical requirements of natural bones. In addition, the hierarchical-stepwise phase transformation in fractal NiTi structures exhibits a statistical power-law behavior, which is compatible with the multiscale failure process during deformation in natural bones. These results indicate that Menger sponge fractal NiTi structures may have great potentials for bone implants. The present design concept of fractal structures may open new avenues in biomechanical capabilities that conventional metal structures cannot achieve.
Designing hexagonal close packed high entropy alloys using machine learning
Authors: Akhil Bejjipurapu , Bajpai Anurag , Gurao Nilesh P , Biswas Krishanu 
Published: September 2021

Abstract
High entropy alloys (HEAs) have drawn significant interest in the materials research community owing to their remarkable physical and mechanical properties. These improved physicochemical properties manifest due to the formation of simple solid solution phases with unique microstructures. Though several pathbreaking HEAs have been reported, the field of alloy design, which has the potential to guide alloy screening, is still an open topic hindering the development of new HEA compositions, particularly ones with hexagonal close packed (hcp) crystal structure. In this work, an attempt has been made to develop an intelligent extra tree (ET) classification model based on the key thermodynamic and structural properties, to predict the phase evolution in HEAs. The results of correlation analysis suggest that all the selected thermodynamic and structural features are viable candidates for the descriptor dataset. Testing accuracy of above 90% along with excellent performance matrices for the ET classifier reveal the robustness of the model. The model can be employed to design novel hcp HEAs and as a valuable tool in the alloy design of HEAs in the future.
Model for current drive induced crash cycles in W7-X
Authors: Aleynikova K. , Hudson S.R. , Helander P. , Kumar A. , Geiger J. , Hirsch M. , Loizu J. , Nührenberg C. , Rahbarnia K. , Qu Z. , Gao Y. , Thomsen H. , Turkin Y. , Zanini M. , W7-X Team the 
Published: September 2021

Abstract
In the Wendelstein 7-X (W7-X) stellarator, the vacuum rotational transform, ι, has a flat radial profile and does not cross any major rational resonance. Nevertheless, during plasma operation the ι‐profile can be strongly modified by electron cyclotron current drive in such a way that the resulting ι-profile passes through low-order rational values, and this can trigger magnetohydrodynamic (MHD) events. Indeed, W7-X plasmas are sometimes subject to repetitive collapses of core confinement, which can be observed regardless of the direction in which the EC current is driven. Even though the origin of these MHD instabilities is under investigation, the crashes may be connected to the formation of magnetic islands and magnetic reconnection. In the present work, we try to shed light on the dynamics of different events happening during the course of sawtooth cycles in W7-X by proposing a model that combines a slow current diffusion with a recipe for fast relaxation that conserves the corresponding helical flux (Kadomtsev 1975 Fiz. Plazmy
1 710–15). We also propose a simple model based on Taylor relaxation (Taylor 1974 Phys. Rev. Lett.
33 1139), (Taylor 1986 Rev. Mod. Phys.
58 741) to predict the nonlinear redistribution of plasma current caused by the largest of the observed events.