bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancing prosthetic hand control: A synergistic multi-channel electroencephalogram
Authors: Maibam Pooya Chanu , Pei Dingyi , Olikkal Parthan , Vinjamuri Ramana Kumar , Kakoty Nayan M. 
Published: November 2024

Abstract
Electromyogram (EMG) has been a fundamental approach for prosthetic hand control. However it is limited by the functionality of residual muscles and muscle fatigue. Currently, exploring temporal shifts in brain networks and accurately classifying noninvasive electroencephalogram (EEG) for prosthetic hand control remains challenging. In this manuscript, it is hypothesized that the coordinated and synchronized temporal patterns within the brain network, termed as brain synergy, contain valuable information to decode hand movements. 32-channel EEGs were acquired from 10 healthy participants during hand grasp and open. Synergistic spatial distribution pattern and power spectra of brain activity were investigated using independent component analysis of EEG. Out of 32 EEG channels, 15 channels spanning the frontal, central and parietal regions were strategically selected based on the synergy of spatial distribution pattern and power spectrum of independent components. Time-domain and synergistic features were extracted from the selected 15 EEG channels. These features were employed to train a Bayesian optimizer-based support vector machine (SVM). The optimized SVM classifier could achieve an average testing accuracy of 94.39

$ \pm $

.84% using synergistic features. The paired t-test showed that synergistic features yielded significantly higher area under curve values (p < .05) compared to time-domain features in classifying hand movements. The output of the classifier was employed for the control of the prosthetic hand. This synergistic approach for analyzing temporal activities in motor control and control of prosthetic hands have potential contributions to future research. It addresses the limitations of EMG-based approaches and emphasizes the effectiveness of synergy-based control for prostheses.
Geodesic Distance Integration in Analytical Frameworks for Aquifer Hydraulic Modeling
Authors: Wen Zhang , Park Eungyu , Xue Peipei , Chen Huali 
Published: November 2024

AbstractTraditional analytical models in groundwater studies often simplify the complexities arising from spatial variations in aquifer geometry and anisotropy, limiting their ability to capture the full theoretical nuances of groundwater flow. In this study, we present a novel methodology that integrates geodesic distances within the intrinsic geometry of confined, constant‐thickness aquifers, while also accounting for directional anisotropy in hydraulic properties. This approach provides a rigorous mathematical framework for accurately capturing the true distances along the aquifer geometry between pumping and observation wells, in contrast to traditional Euclidean distances. Our methodology is compatible with various analytical solutions, including the Theis (1935, https://doi.org/10.1111/jawr.1965.1.3.9) and Papadopulos and Cooper (1967, https://doi.org/10.1029/wr003i001p00241) solutions, extending their theoretical applicability to more complex aquifer geometries and anisotropic conditions. Numerical simulations of synthetic examples illustrate the theoretical consistency of the proposed approach, aligning drawdown patterns within this advanced framework. While primarily focused on enhancing existing analytical models, this methodology sets the stage for future theoretical advances in groundwater modeling, offering a conceptual expansion of analytical solutions to better address geometric and anisotropic complexities.
A study of liquidity cross-chain models based on convex optimization
Authors: Han Yutong , Wang Chundong , Wang Huaibin , Yang Yi , Wang Xi 
Published: November 2024

AbstractBlockchain after several years of hustle, bustle, precipitation, and sublimation, with the landing application step by step towards maturity and development, gradually spawned the outreach needs of interacting with other applications. At this stage, only the mobility cross-chain interoperability technology is the infrastructure system that can perfectly solve such needs. To achieve a cross-chain system that defines and realizes user-free liquidity interoperability according to the cross-chain environment and cross-chain requirements, this paper designs a convex optimization-based liquidity contract pair cross-chain model. This model can realize a uniform distributed NFT ID construction identification method for the whole chain, and at the same time use the convex optimization model to obtain liquidity contract pairs that have and only have the global optimal matching, and in this way lock the shortest cross-chain time required, with AMM bonding curve management to achieve immediate liquidity effect, and realize the interconnection and interoperability of users’ assets with free liquidity. Finally, the time-consumption, robustness, and radius of convergence of the models are tested by comparing the model experiments and the proposed model’s proposed cross-chain incentive experiments yield results that verify that the proposed convex optimization-based liquidity contract is efficient, applicable, and secure for cross-chain models.
Susceptibility-induced internal gradients reveal axon morphology and cause anisotropic effects in the diffusion-weighted MRI signal
Authors: Winther S. , Lundell H. , Rafael-Patiño J. , Andersson M. , Thiran J.-P. , Dyrby T. B. 
Published: November 2024

AbstractDiffusion-weighted MRI is our most promising method for estimating microscopic tissue morphology in vivo. The signal acquisition is based on scanner-generated external magnetic gradients. However, it will also be affected by susceptibility-induced internal magnetic gradients caused by interactions between the tissue and the static magnetic field of the scanner. With 3D in silico experiments, we show how internal gradients cause morphology-, compartment-, and orientation-dependence of spin-echo and pulsed-gradient spin-echo experiments in myelinated axons. These effects surpass those observed with previous 2D modelling corresponding to straight cylinders. For an ex vivo monkey brain, we observe the orientation-dependence generated only when including non-circular cross-sections in the in silico morphological configurations, and find orientation-dependent deviation of up to 17% for diffusion tensor metrics. Interestingly, we find that the orientation-dependence not only biases the signal across different brain regions, but also carries a sensitivity to the morphology of axonal cross-sections which is not attainable by the idealised theoretical diffusion-weighted MRI signal.
The effect of dynamic temperatures on pebble dynamics and planet formation
Authors: Castrejon Areli , Min Michiel , Kamp Inga , Jørgensen Uffe Gråe 
Published: November 2024

Context. To date, more than 5000 exoplanets have been discovered. The large majority of these planets have a mass between 1 and 17 M⊕, making them so-called super-Earths and mini-Neptunes. The exact formation process for this abundant planet population has not yet been fully constrained.
Aims. Recent studies on the formation of these planets make various assumptions with regard to the disk. The primary mass budget, held in pebbles, is either assumed to have a constant size or is parametrized as a flux. Simplifications of the temperature structure, in the form of a static power law, do not consider the temperature evolution and high magnitudes of heating in the inner part of the disk. In this study, we aim to investigate the effect these simplifications of temperature and pebble sizes have on the pebble densities and resulting planet populations.
Methods. To constrain the timescales needed to form super-Earths, we developed a model for exploring a large parameter space. We included the effect of two different temperature prescriptions on a viscously accreting and spreading disk. We formed a pebble reservoir utilizing a simplified conversion timescale with a time- and radially dependent Stokes number for the dust. We then tracked the temporal evolution of the surface densities of gas, dust, and pebbles. Pebbles were allowed to drift and be accreted onto a growing protoplanet. As a planet grows, it exerts a torque on the disk, carving out a gap and affecting the pebble drift, before halting the growth of the planet.
Results. We find that viscous heating has a significant effect on the resulting mass populations, with the static power law showing smaller planets within 10 AU. Inside the dust-sublimation line, usually within 0.5 AU, planet formation is reduced due to the loss of planet-forming material. Our model replicates observed planet masses between Earth and mini-Neptune sizes at all radial locations, with the most massive planets growing in the intermediate turbulence of α = 10−3.
Conclusions. We conclude that a self-consistent treatment of temperature, with the inclusion of a dust-sublimation line, is important and could explain the high occurrence of super-Earths at short orbital separations.
A new sample of super-slowly rotating Ap (ssrAp) stars from the Zwicky Transient Facility survey
Authors: Hümmerich S. , Bernhard K. , Paunzen E. 
Published: November 2024

Context. The magnetic chemically peculiar Ap stars exhibit an extreme spread of rotational velocities, the cause of which is not clearly understood. Ap stars with rotation periods of 50 days or longer are know as super-slowly rotating Ap (ssrAp) stars. Photometrically variable Ap stars are commonly termed α2 Canum Venaticorum (ACV) variables.
Aims. Our study aims to enlarge the sample of known ssrAp stars using data from the Zwicky Transient Facility (ZTF) survey to enable more robust and significant statistical studies of these objects.
Methods. Using selection criteria based on the known characteristics of ACV variables, candidate stars were gleaned from the ZTF catalogues of periodic and suspected variable stars and from ZTF raw data. ssrAp stars were identified from this list via their characteristic photometric properties, Δa photometry, and spectral classification.
Results. The final sample consists of 70 new ssrAp stars, which mostly exhibit rotation periods of between 50 and 200 days. The object with the longest period has a rotation period of 2551.7 days. We present astrophysical parameters and a Hertzsprung-Russell diagram for the complete sample of known ssrAp stars. With very few exceptions, the ssrAp stars are grouped in the middle of the main sequence with ages in excess of 150 Myr. ZTF J021309.72+582827.7 was identified as a possible binary star harbouring an Ap star and a cool component, possibly shrouded in dust.
Conclusions. With our study, we enlarge the sample of known ssrAp stars by about 150%, paving the way for more in-depth statistical studies.
High-resolution observational analysis of flare ribbon fine structures
Authors: Thoen Faber Jonas , Joshi Reetika , van der Voort Luc Rouppe , Wedemeyer Sven , Fletcher Lyndsay , Aulanier Guillaume , Nóbrega-Siverio Daniel 
Published: November 2024

Context. Since the mechanism of energy release from solar flares is still not fully understood, the study of fine-scale features developing during flares becomes important for progressing towards a consistent picture of the essential physical mechanisms.
Aims. Solar flares release most of their luminous energy in the chromosphere. These luminous signatures, known as flare ribbons, act as the footpoints of the released energy and are crucial for the interpretation of reconnection processes causing these events. We aim to probe the fine structures in flare ribbons at the chromospheric level using high-resolution observations with imaging and spectral techniques.
Methods. We present a GOES C2.4 class solar flare (SOL2022-06-26T08:12) observed with the Swedish 1-m Solar Telescope (SST), the Interface Region Imaging Spectrograph (IRIS), and the Atmospheric Imaging Assembly (AIA). Utilising imaging data from SST, IRIS, and AIA, we detail both the global and fine-structure evolution of the flare. The high-resolution SST observations offer spectroscopic data in the Hα, Ca II 8542 Å, and Hβ lines, which we use to analyse the flare ribbon.
Results. The flare was associated with a filament eruption. Fibrils and coronal loops were connected from a negative polarity region to two positive polarity regions. Within the eastern flare ribbon, chromospheric bright blobs were detected and analysed in Ca II 8542 Å, Hα, and Hβ wavelengths. A comparison of blobs in Hβ observations and Si IV 1400 Å has also been performed. These blobs are observed as almost circular structures having widths from 140 km–200 km. The intensity profiles of the blobs show a red wing asymmetry.
Conclusions. From the high spatial and temporal resolution Hβ observations, we conclude that the periodicity of the blobs in the flare ribbon, which are near-equally spaced in the range 330–550 km, is likely due to fragmented reconnection processes within a flare current sheet. This supports the theory of a direct link between fine-structure flare ribbons and current sheet tearing. We believe our observations represent the highest resolution evidence of fine-structure flare ribbons to date.
Ärztliche Führung im Krankenhaus der Zukunft
Authors: Balling Stephan , Bohnet-Joschko Sabine 
Published: November 2024

Zusammenfassung
Zielsetzung Wir untersuchen, welche Kompetenzen für ärztliche Führungskräfte im Krankenhaus der Zukunft relevant sind.
Methodik Einschätzungen von Akteuren und Stakeholdern aus dem Gesundheitswesen wurden in einem qualitativen Design durch Experteninterviews erhoben.
Ergebnisse Medizinische Fachlichkeit dominiert bei der Besetzung ärztlicher Führungspositionen. Analytisches und strategisches Denken, Organisationstalent und Entscheidungsfreude, Kommunikationsfähigkeit, Verständnis für betriebswirtschaftliche Zusammenhänge, Wissen zu Versorgungssystemen und Ethik sowie Veränderungs- und Digitalkompetenz gewinnen an Bedeutung.
Schlussfolgerung Gute ärztliche Führungskräfte sind kommunikativ stark, Visionäre und Leitbildgeber und bringen die Fähigkeit zur Veränderung mit. Besondere technische Fähigkeiten wie Programmiersprachen sind hingegen nicht bedeutend.
Influence of initial speciation of platinum and palladium on their accumulation and toxicity towards phytoplankton
Authors: Michaud-Valcourt Julien , Blanc Sylvie , Courtois Louis , Mertens Jelle , Le Faucheur Séverine , Fortin Claude 
Published: November 2024

Environmental context The increasing global demand for platinum and palladium for the development of new technologies will likely enhance their biogeochemical mobility. However, our understanding of the environmental risks of these metals remains incomplete. To help fill this knowledge gap, we determined the toxicity of various forms of platinum and palladium on a green alga. We found that palladium was more toxic than platinum and that platinum toxicity depended on the form tested. Rationale Chemical equilibrium-based models such as the biotic ligand model (BLM) can be used to predict metal toxicity towards aquatic organisms. However, some metals such as platinum (Pt) and to a lesser extent palladium (Pd) are known to be kinetically hindered, i.e. reactions between these elements and ligands in solution might be slow relative to the biota exposure time. The BLM applicability may thus be limited for these metals and their ecological risk assessment may require consideration of their initial form of entry in aquatic ecosystems. Methodology This study investigates the relationship between inorganic Pt and Pd initial speciation and their bioavailability and toxicity toward the unicellular green alga Raphidocelis subcapitata. Chloro- or amino-coordinated Pt and Pd complexes such as PtIICl42−, PtIVCl62−, PtII(NH3)42+, PdIICl42− and PdII(NH3)42+ were examined in 96-h algae exposure experiments to determine growth inhibition and metal accumulation. Investigation of the complex stability over time of the tested complexes was carried out using spectrophotometry measurements and kinetic calculations. Results Similar accumulation and no toxicity (half maximal effective concentration, EC50 > 150 µg L−1) were observed for both in our tested conditions. Nevertheless, evidence of PtIICl42− dissociation was observed whereas PtII(NH3)42+ was stable. Exposure to PtIVCl62− showed stronger algal growth inhibition (EC50 = 142 µg L−1) than exposure to PtIICl42− but similar accumulation. This phenomenon might be partly explained by the generation of free chloride radicals through PtIV reduction in the presence of light. Similar accumulation and toxicity were observed for both PdIICl42− (EC50 = 4.69 µg L−1) and PdII(NH3)42+ (EC50 = 2.40 µg L−1). Discussion These results were coherent with the relatively rapid speciation changes of the PtII complexes as observed and modelled. We therefore conclude that the initial speciation of the studied chloro- and amino-coordinated PtII and PdII complexes is not a determining parameter of their accumulation and toxicity towards R. subcapitata.
Double copy, Kerr–Schild gauges and the effective-one-body formalism
Authors: Ceresole Anna , Damour Thibault , Nagar Alessandro , Rettegno Piero 
Published: November 2024

Abstract
We look for a classical double-copy-inspired relation between gravity and electrodynamics by connecting the descriptions of the scattering of two point masses, and of two point charges, in terms of perturbative (post-Minkowskian or post-Lorentzian) expansions. We do so by recasting available analytical information within the effective-one-body formalism using Kerr–Schild gauges in both cases. Working at the third perturbative level, we find that the usual linear relation (holding in the probe limit) between the adimensionalized electric potential,

ϕ
~

=

G
M

e
1

e
2

ϕ

el

, and the Schwarzschild-like gravitational one,

Φ

grav

, is deformed, in the comparable-mass, comparable-charge, case, into a nonlinear relation which becomes universal in the high energy limit:

Φ

grav

=
2

ϕ
~

−
5

ϕ
~

2

+
18

ϕ
~

3

.
On the overlap reduction function of pulsar timing array searches for gravitational waves in modified gravity
Authors: Cordes Nina , Mitridate Andrea , Schmitz Kai , Schröder Tobias , Wassner Kim 
Published: November 2024

Abstract
Pulsar timing array (PTA) searches for gravitational waves (GWs) aim to detect a characteristic correlation pattern in the timing residuals of galactic millisecond pulsars. This pattern is described by the PTA overlap reduction function (ORF)

Γ

a
b

(

ξ

a
b

)

, which is known as the Hellings–Downs (HD) curve in general relativity (GR). In theories of modified gravity, the HD curve often receives corrections. Assuming, e.g. a subluminal GW phase velocity, one finds a drastically enhanced ORF in the limit of small angular separations between pulsar a and pulsar b in the sky,

ξ

a
b

→
0

. In particular, working in harmonic space and performing an approximate resummation of all multipole contributions, the auto correlation coefficient Γ

aa
seems to diverge. In this paper, we confirm that this divergence is unphysical and provide an exact and analytical expression for Γ

aa
in dependence of the pulsar distance La
and the GW phase velocity

v

ph

. In the GR limit and assuming a large pulsar distance, our expression reduces to

Γ

a
a

=
1

. In the case of subluminal phase velocity, we show that the regularization of the naive divergent result is a finite-distance effect, meaning that Γ

aa
scales linearly with fLa
, where f is the GW frequency. For superluminal phase velocity (subluminal group velocity), which is relevant in the case of massive gravity, we correct an earlier analytical result for Γ

ab
. Our results pave the way for fitting modified-gravity theories with nonstandard phase velocity to PTA data, which requires a proper understanding of the auto correlation coefficient Γ

aa
.
Strong alignment of micro-rotation and vorticity in 3D micropolar flows*
Authors: Guterres R H , Melo W G , Niche C J , Perusato C F , Zingano P R 
Published: November 2024

Abstract
Rigid particles suspended on a micropolar fluid provide microstructure that coexists and interacts with the local rotation of the fluid given by the vorticity. In this work we prove that the particles’ angular velocity and the vorticity strongly align for large times. We provide average and supnorm estimates for the decay rate of the difference between these two vectors, which measures the alignment.
Superconductor bistable vortex memory for data storage and readout
Authors: Karamuftuoglu M A , Ucpinar B Z , Razmkhah S , Pedram M 
Published: November 2024

Abstract
Despite superconductor electronics (SCE) advantages, the realization of SCE logic faces a significant challenge due to the absence of dense and scalable nonvolatile memory. While various nonvolatile memory technologies, including Non-destructive readout, vortex transitional memory, and magnetic memory, have been explored, designing a dense crossbar array and achieving a superconductor random-access memory remains challenging. This work introduces a novel, nonvolatile, high-density, and scalable vortex-based memory design for SCE logic called bistable vortex memory. Our proposed design addresses scaling issues with an estimated area of 10 × 10 um2 while boasting zero static power with the dynamic energy consumption of 12 aJ for single-bit read and write operations. The current summation capability enables analog operations for in-memory or near-memory computational tasks. We demonstrate the efficacy of our approach with a 32 × 32 superconductor memory array operating at 20 GHz. Additionally, we showcase the accumulation property of the memory through analog simulations conducted on an 8 × 8 superconductor crossbar array.
Comparison of

J
c

measurements obtained by magnetisation and transport methods for a GdBCO-Ag bulk
Authors: Taylor R W , Pantoja A E , Chong S V , Hlásek T , Plecháček J , Weijers H W , Ainslie M D , Badcock R A , Bumby C W 
Published: November 2024

Abstract
Accurate numerical modelling of bulk rare-earth barium cuprate ((RE)BCO) high-temperature superconductors requires measured data of the temperature and magnetic field dependence of the critical current density,

J
c

, and flux-flow exponent, n. However, there is limited published

J
c

and n data for modern (RE)BCO bulks. In this work, transport and magnetisation methods were applied to characterise

J
c

, n, and the critical temperature,

T
c

, of a commercially available top-seeded melt growth (TSMG) GdBCO-Ag bulk. Both measurement methods exhibit good quantitative and qualitative agreement when the transport electric field criterion is scaled from 1

μ

V

cm

−
1

to 10−4

μ

V

cm

−
1

. Transport-derived thermo-magneto-angular dependent

J
c

data for the TSMG GdBCO-Ag bulk are compared to equivalent data for a SuNAM SCN12700 GdBCO coated-conductor tape. Significant qualitative differences are observed between the data for the bulk and tape, with the tape data featuring neither a fishtail effect nor a

B
∥
c

peak, both of which are present in the bulk data. A reliable sample preparation and mounting method is presented, which enables the transport characterisation of (RE)BCO bulk superconductors over a large range of temperatures and applied field magnitudes and angles. All

J
c

and n data presented within this manuscript are available in the supplementary material, and can be interpolated into finite-element models to more accurately capture the superconducting behaviour of GdBCO superconductors.
Distinguishability-induced many-body decoherence
Authors: Dittel Christoph , Buchleitner Andreas 
Published: November 2024

Abstract
We show that many-body interference phenomena are exponentially suppressed in the particle number, if the identical quantum objects brought to interference acquire a finite level of distinguishability through statistical mixing of some internal, unobserved degrees of freedom. We discuss consequences for cold atom and photonic circuitry experiments.