bluuebunny/crossref_metadata_2025_split huggingface dataset:
Understanding the natural units and their hidden role in the laws of physics
Authors: Humpherys David 
Published: July 2024

Abstract
The natural units of measure lauded by Max Planck more than 100 years ago are underutilized today. Many physical constants, including the Planck constant, the gravitational constant, the speed of light, vacuum permittivity, and vacuum permeability consist of natural units in their unit dimensions. The natural units are present in all formulas containing these constants. The defining characteristic of the natural units is an alignment of unit values at the Planck scale. This alignment gives a computational basis of proportionality from which the correlated properties and dynamics of elementary particles, including wavelength, period, mass, momentum, and energy, manifest in equal or inversely proportional ratios of the Planck scale. These correlations explain many of the defining equations of quantum mechanics, classical gravity, and electromagnetism.
Comparative analysis of absorption resonances between carbynes and cyclo

[
n
]

carbons
Authors: Payod Renebeth B , Pushkarchuk Aliaxandr L , Michels Dominik L , Lyakhov Dmitry A , Saroka Vasil A 
Published: July 2024

Abstract
Two approaches are presented here to analyze the absorption resonances between carbynes and cyclo

[
n
]

carbons, namely the analytical tight-binding model to calculate the optical selection rules of cumulenic atomic rings and chains and the ab initio time-dependent density functional theory for the optical investigation of polyynic carbon ring and chains. The optical absorption spectra of the carbon ring match that of the finite chain when their eigen energies align following the

N

ring

=
2

N

chain

+
2

rule, which states that the number of atoms in an atomic ring

N

ring

is twice the number of atoms on a finite chain

N

chain

with two additional atoms. Two representative atomic chains are chosen for our numerical calculations, specifically carbynes with

N
=
7

and

8

carbon atoms as optical resonance spectra match to a recently synthesized carbon ring called cyclo[18]carbon. Despite the mismatch in resonance peaks, molecular orbital transitions of both carbynes N = 7 and 8 and cyclo[18]carbon reveal a wave function symmetry change from inversion to reflection and vice versa for allowed molecular orbital transitions, which results in electron density redistribution along the polyynic carbyne axis or the cyclo[18]carbon circumference. Our investigation of the correlation of optical absorption peaks between carbynes and cyclo

[
n
]

carbons is a step towards enhancing the reliability of allotrope identification in advanced molecular device spectroscopy. Moreover, this work could facilitate the non-invasive, rapid and crucial assessment of these sensitive 1D allotropes by providing accurate descriptions of their electronic and optical properties, particularly in controlled synthesis environments.
DiffuseRT: predicting likely anatomical deformations of patients undergoing radiotherapy
Authors: Smolders A , Rivetti L , Vatterodt N , Korreman S , Lomax A , Sharma M , Studen A , Weber D C , Jeraj R , Albertini F 
Published: July 2024

Abstract

Objective. Predicting potential deformations of patients can improve radiotherapy treatment planning. Here, we introduce new deep-learning models that predict likely anatomical changes during radiotherapy for head and neck cancer patients. Approach. Denoising diffusion probabilistic models (DDPMs) were developed to generate fraction-specific anatomical changes based on a reference cone-beam CT (CBCT), the fraction number and the dose distribution delivered. Three distinct DDPMs were developed: (1) the image model was trained to directly generate likely future CBCTs, (2) the deformable vector field (DVF) model was trained to generate DVFs that deform a reference CBCT and (3) the hybrid model was trained similarly to the DVF model, but without relying on an external deformable registration algorithm. The models were trained on 9 patients with longitudinal CBCT images (224 CBCTs) and evaluated on 5 patients (152 CBCTs). Results. The generated images mainly exhibited random positioning shifts and small anatomical changes for early fractions. For later fractions, all models predicted weight losses in accordance with the training data. The distributions of volume and position changes of the body, esophagus, and parotids generated with the image and hybrid models were more similar to the ground truth distribution than the DVF model, evident from the lower Wasserstein distance achieved with the image (0.33) and hybrid model (0.30) compared to the DVF model (0.36). Generating several images for the same fraction did not yield the expected variability since the ground truth anatomical changes were only in 76% of the fractions within the 95% bounds predicted with the best model. Using the generated images for robust optimization of simplified proton therapy plans improved the worst-case clinical target volume V95 with 7% compared to optimizing with 3 mm set-up robustness while maintaining a similar integral dose. Significance. The newly developed DDPMs generate distributions similar to the real anatomical changes and have the potential to be used for robust anatomical optimization.
Present and future of

C

osmo

L

attice
Authors: Figueroa Daniel G , Florio Adrien , Torrenti Francisco 
Published: July 2024

Abstract
We discuss the present state and planned updates of

C

osmo

L

attice, a cutting-edge code for lattice simulations of non-linear dynamics of scalar-gauge field theories in an expanding background. We first review the current capabilities of the code, including the simulation of interacting singlet scalars and of Abelian and non-Abelian scalar-gauge theories. We also comment on new features recently implemented, such as the simulation of gravitational waves from scalar and gauge fields. Secondly, we discuss new extensions of

C

osmo

L

attice that we plan to release publicly. We comment on new physics modules, which include axion-gauge interactions

ϕ
F

F
~

, non-minimal gravitational couplings

ϕ
2

R

, creation and evolution of cosmic-defect networks, and magnetohydrodynamics. We also discuss new technical features, including evolvers for non-canonical interactions, arbitrary initial conditions, simulations in 2+1 dimensions, and higher-accuracy spatial derivatives.
A two-step modeling method for constructing 3D negative Poisson’s ratio materials with high specific strength based on common lattice structures
Authors: Lv Weitao , Li Dong 
Published: July 2024

Abstract
The traditional negative Poisson’s ratio (NPR) structure was basically designed based on concave or rotational mechanisms, resulting in relatively low specific strength and limiting its application. This paper proposed a two-step modeling method to establish a connection between the common lattice structures and NPR structures, which can obtain NPR structures with high specific strength. The models with different triaxial compression ratios were obtained through triaxial compression FE simulation to the selected initial configuration. Then, the mechanical properties of these models were studied through uniaxial compression FE simulation and experiments. In the research scope of this paper, the results demonstrate that the lattice structure can get NPR through the two-step modeling method when the Maxwell’s number is less than or equal to zero. The specific strength of the NPR structure obtained through the two-step modeling method was at most 1.5 times higher than that of the traditional 3D star-shaped NPR structure. Due to the high designability and excellent mechanical properties of lattice structures, this work provides a novel method for the manufacture of NPR structures with high specific strength.
Synthesis of MgB2 films on Hastelloy-C276 tape with Al2O3/Y2O3/MgO/LaMnO3 buffer layers by magnetron sputtering in co-evaporation mode
Authors: Yanilkin I V , Gumarov A I , Rudnev I A , Fatikhova L R , Kiiamov A G , Denisov A E , Khokhorin S A , Tayurskii D A , Batulin R G 
Published: July 2024

Abstract
This study presents the initial results of developing a technology for synthesizing a flexible superconducting magnesium diboride composite on a Hastelloy®-C276TM substrate coated with Al2O3/Y2O3/MgO/LaMnO3 buffer layers. The superconducting composite was deposited by magnetron sputtering from two Mg and B targets, followed by vacuum annealing at various substrate temperatures ranging from 400 °C to 700 °C. The superconducting transition temperature T
c ≈ 22 K, with a transition width ΔT ≈ 1 K, and critical current J
c ≈ 500 kA cm−2 (T= 5 K, H = 2 T) and J
c ≈ 11 kA cm−2 (T = 15 K, H = 2 T) at the optimal annealing temperature of 400 °C.
Measurement of Gaussian laser beam radius using nanosecond-pulse laser etching of titanium film
Authors: Lu Wenxuan , Chen Qinrui , Sun Wanshou , Guo Liang , Zhang Qingmao 
Published: July 2024

Abstract
A method for measuring the Gaussian laser beam radius based on nanosecond-pulse laser etching (NPLE) was proposed. The NPLE method has the advantages of simple operation, low cost and high accuracy. It can be used to directly measure the laser beam size in the range of 0.25 ∼ 6 W without attenuating the laser energy. In the experiments, 1064 nm pulsed laser beam was used to etch titanium film, the size and position of the laser beam waist were measured. The experimental results are consistent with the calibration values of the CCD method, it indicates that the NPLE method is feasible.
Mechanical characteristics and electrochemical corrosion of NiCoCr alloys
Authors: Lu Yu-Sheng , Bui Thi-Xuyen , Fang Te-Hua 
Published: July 2024

Abstract
Previous studies have shown that NiCoCr medium entropy alloys (MEAs) have perfect strength-ductility balance and significant escape fracture toughness. This work aimed to determine the effects of annealing temperature and alloy composition on the mechanical characteristics and corrosion behaviors of the NiCoCr MEAs. The results showed that the grains generated in the NiCoCr MEAs became more petite with the cooling rate increasing. The Vickers hardness (HV) of annealed NiCoCr MEAs increased with increasing annealing temperature. For NiCoCr alloys with different alloy compositions, the potentiodynamic polarization results showed that the NiCoCrFeMn alloy has the highest polarisation resistance, lowest current density, and lowest corrosion rate. However, the composition of Fe2O3-based passivation film makes it highly reactive and easily cleaved by Cl−. The NiCoCr and NiCoCrFe MEAs with high Ni content had a denser and slowly dissolved NiO passivation layer and better corrosion resistance. Moreover, the hardness of corroded NiCoCr MEAs decreased by 7.7%.
Investigation of numerical transport models in protein-based molecular junctions with cofactors of diverse chemical natures
Authors: Ramya Kunchanapalli , Mukhopadhyay Sabyasachi 
Published: July 2024

Abstract
The cofactors of proteins dictate the charge transport mechanism across molecular junctions when self-assembled protein monolayers are sandwiched between two metal electrodes. Here, we summarized how the chemical coordination nature of cofactors in various proteins modulates electrical conductance by investigating electronic transport studies across different protein-based molecular junctions under various forces applied under the AFM tip. We have utilized several numerical techniques of electronic transport to analyse the experimentally obtained current–voltage measurements across various protein-based molecular junctions and depicted the origin of electronic modulation in the electrical conductance under different external stimuli. We could also find the origin of electronic conductance modulation under external stimuli at various applied forces by obtaining several analytical transport parameters such as energy barrier, coupling strength, and electrical conductance values. Utilizing density-functional-theory calculations, we further validate that the electronic density of states present in the cofactors within the proteins dominates the electronic transport behaviours across protein-based molecular junctions. Our findings reveal the limiting factor for applying various external stimuli on different proteins, which could be further valuable in bioelectronic applications. We have also found that the organic cofactor containing protein follows all the tunneling mechanism-related numerical transport models and the electronic transport across proteins with pure inorganic cofactors follows Landauer transport formalism.
How to design optimal brain stimulation to modulate phase-amplitude coupling?
Authors: Duchet Benoit , Bogacz Rafal 
Published: July 2024

Abstract

Objective. Phase-amplitude coupling (PAC), the coupling of the amplitude of a faster brain rhythm to the phase of a slower brain rhythm, plays a significant role in brain activity and has been implicated in various neurological disorders. For example, in Parkinson’s disease, PAC between the beta (13–30 Hz) and gamma (30–100 Hz) rhythms in the motor cortex is exaggerated, while in Alzheimer’s disease, PAC between the theta (4–8 Hz) and gamma rhythms is diminished. Modulating PAC (i.e. reducing or enhancing PAC) using brain stimulation could therefore open new therapeutic avenues. However, while it has been previously reported that phase-locked stimulation can increase PAC, it is unclear what the optimal stimulation strategy to modulate PAC might be. Here, we provide a theoretical framework to narrow down the experimental optimisation of stimulation aimed at modulating PAC, which would otherwise rely on trial and error. Approach. We make analytical predictions using a Stuart–Landau model, and confirm these predictions in a more realistic model of coupled neural populations. Main results. Our framework specifies the critical Fourier coefficients of the stimulation waveform which should be tuned to optimally modulate PAC. Depending on the characteristics of the amplitude response curve of the fast population, these components may include the slow frequency, the fast frequency, combinations of these, as well as their harmonics. We also show that the optimal balance of energy between these Fourier components depends on the relative strength of the endogenous slow and fast rhythms, and that the alignment of fast components with the fast rhythm should change throughout the slow cycle. Furthermore, we identify the conditions requiring to phase-lock stimulation to the fast and/or slow rhythms. Significance. Together, our theoretical framework lays the foundation for guiding the development of innovative and more effective brain stimulation aimed at modulating PAC for therapeutic benefit.
Connectivity study on resting-state EEG between motor imagery BCI-literate and BCI-illiterate groups
Authors: Park Hanjin , Jun Sung Chan 
Published: July 2024

Abstract

Objective. Although motor imagery-based brain-computer interface (MI-BCI) holds significant potential, its practical application faces challenges such as BCI-illiteracy. To mitigate this issue, researchers have attempted to predict BCI-illiteracy by using the resting state, as this was found to be associated with BCI performance. As connectivity’s significance in neuroscience has grown, BCI researchers have applied connectivity to it. However, the issues of connectivity have not been considered fully. First, although various connectivity metrics exist, only some have been used to predict BCI-illiteracy. This is problematic because each metric has a distinct hypothesis and perspective to estimate connectivity, resulting in different outcomes according to the metric. Second, the frequency range affects the connectivity estimation. In addition, it is still unknown whether each metric has its own optimal frequency range. Third, the way that estimating connectivity may vary depending upon the dataset has not been investigated. Meanwhile, we still do not know a great deal about how the resting state electroencephalography (EEG) network differs between BCI-literacy and -illiteracy. Approach. To address the issues above, we analyzed three large public EEG datasets using three functional connectivity and three effective connectivity metrics by employing diverse graph theory measures. Our analysis revealed that the appropriate frequency range to predict BCI-illiteracy varies depending upon the metric. The alpha range was found to be suitable for the metrics of the frequency domain, while alpha + theta were found to be appropriate for multivariate Granger causality. The difference in network efficiency between BCI-literate and -illiterate groups was constant regardless of the metrics and datasets used. Although we observed that BCI-literacy had stronger connectivity, no other significant constructional differences were found. Significance. Based upon our findings, we predicted MI-BCI performance for the entire dataset. We discovered that combining several graph features could improve the prediction’s accuracy.
Recording of single-unit activities with flexible micro-electrocorticographic array in rats for decoding of whole-body navigation
Authors: Lo Yu Tung , Jiang Lei , Woodington Ben , Middya Sagnik , Braendlein Marcel , Lam Jordan Lewis William , Lim Mervyn Jun Rui , Ng Vincent Yew Poh , Rao Jai Prashanth , Chan Derrick Wei Shih , Ang Beng Ti 
Published: July 2024

Abstract

Objective. Micro-electrocorticographic (μECoG) arrays are able to record neural activities from the cortical surface, without the need to penetrate the brain parenchyma. Owing in part to small electrode sizes, previous studies have demonstrated that single-unit spikes could be detected from the cortical surface, and likely from Layer I neurons of the neocortex. Here we tested the ability to use μECoG arrays to decode, in rats, body position during open field navigation, through isolated single-unit activities. Approach. μECoG arrays were chronically implanted onto primary motor cortex (M1) of Wistar rats, and neural recording was performed in awake, behaving rats in an open-field enclosure. The signals were band-pass filtered between 300–3000 Hz. Threshold-crossing spikes were identified and sorted into distinct units based on defined criteria including waveform morphology and refractory period. Body positions were derived from video recordings. We used gradient-boosting machine to predict body position based on previous 100 ms of spike data, and correlation analyses to elucidate the relationship between position and spike patterns. Main results. Single-unit spikes could be extracted during chronic recording from μECoG, and spatial position could be decoded from these spikes with a mean absolute error of prediction of 0.135 and 0.090 in the x- and y- dimensions (of a normalized range from 0 to 1), and Pearson’s r of 0.607 and 0.571, respectively. Significance. μECoG can detect single-unit activities that likely arise from superficial neurons in the cortex and is a promising alternative to intracortical arrays, with the added benefit of scalability to cover large cortical surface with minimal incremental risks. More studies should be performed in human related to its use as brain–machine interface.
Limitations to extracellular concentration sensing through signaling cascades
Authors: Biswal Swoyam Srirupa , Wasnik Vaibhav 
Published: July 2024

Abstract
Signaling cascades refer to sequential biochemical reactions that occur in the cytoplasm of living cells in response to the binding of a ligand to a cell surface receptor, triggering a cellular response. Living cells need to sense extracellular concentrations with high precision. In this paper, we study the limitations of extracellular concentration measurement in linear signaling cascades. We find that as long as the cascade is linear and measurement times are much larger or much smaller than the timescales of the cytoplasmic reactions, the error in concentration measurement is independent of cascade length, the nature of the reactions and their rates. Our results can also be extended to generic non-linear signal cascades when the measurement time is much smaller than the timescales of cytoplasmic reactions. We illustrate this by considering the specific example of the accuracy of concentration detection in E. coli.
Discharge and mass transfer characteristics of atmospheric pressure gas-solid two-phase gliding arc
Authors: ZHU 朱 Min 珉 , PING 平 Yuchen 宇辰 , ZHANG 张 Yinghao 英豪 , ZHANG 张 Chaohai 潮海 , WU 吴 Shuqun 淑群 
Published: July 2024

Abstract
In this work, a gas-solid two-phase gliding arc discharge (GS-GAD) reactor was built. Gliding arc was formed in the gap between the blade electrodes, and solid powder was deposited on the sieve plate positioned beneath the blade electrodes. A range of experimental parameters, including the inter-electrode spacing, gas flow rate, applied voltage, and the type of the powder, were systematically varied to elucidate the influence of solid powder matter on the dynamics of gliding arc discharge (GAD). The discharge images were captured by ICCD and digital camera to investigate the mass transfer characteristics of GS-GAD, and the electrical parameters, such as the effective values of voltage, current, and discharge power were record to reveal the discharge characteristics of GS-GAD. The results demonstrate that powder undergoes spontaneous movement towards the upper region of the gliding arc due to the influence of electric field force. Increasing the discharge voltage, decreasing relative dielectric constant of the powder and reducing the electrode-to-sieve-plate distance all contribute to a greater involvement of powder in the GAD process, subsequently resulting in an enhanced powder concentration within the GAD region. Additionally, powder located beneath the gliding arc experiences downward resistance caused by the opposing gas flow and arc. Excessive gas flow rate notably hampers the powder concentration within the discharge region, and the velocity of powder motion in the upper part of the GAD region is reduced. Under the condition of electrode-to-sieve-plate distance of 30 mm, gas flow rate of 1.5 L/min, and peak-to-peak voltage of 31 kV, the best combination of arc gliding and powder spark discharge phenomena can be achieved with the addition of Al2O3 powder.