bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyp size measurement during colonoscopy using a virtual scale: variability and systematic differences
Authors: van Bokhorst Querijn N. E. , Houwen Britt B. S. L. , Hazewinkel Yark , van der Vlugt Manon , Beaumont Hanneke , Grootjans Joep , van Tilburg Arjan , Fockens Paul , Bossuyt Patrick M. M. , Dekker Evelien ,   on behalf of the SCALE EYE study group
Published: July 2024

Background Accurate polyp size measurement is important for polyp risk stratification and decision-making regarding polypectomy and surveillance. Recently, a virtual scale (VS) function has been developed that allows polyp size measurement through projection of an adaptive VS onto colorectal polyps during real-time endoscopy. We aimed to evaluate the VS in terms of variability and systematic differences.
Methods We conducted a video-based study with 120 colorectal polyps, measured by eight dedicated colorectal gastroenterologists (experts) and nine gastroenterology residents following endoscopy training (trainees). Three endoscopic measurement methods were compared: (1) visual, (2) snare and (3) VS measurement. We evaluated the method-specific variance (as measure of variability) in polyp size measurements and systematic differences between these methods.
Results Variance in polyp size measurements was significantly lower for VS measurements compared to visual and snare measurements for both experts (0.52 vs. 1.59 and 1.96, p < 0.001) and trainees (0.59 vs. 2.21 and 2.53, p < 0.001). VS measurement resulted in a higher percentage of polyps assigned to the same size category by all endoscopists compared to visual and snare measurements (experts: 69 % vs. 55 % and 59 %; trainees: 67 % vs. 51 % and 47 %) and reduced the maximum difference between individual endoscopists regarding the percentage of polyps assigned to the ≥ 10 mm size category (experts: 1.7 % vs. 10.0 % and 5.0 %; trainees: 2.5 % vs. 6.7 % and 11.7 %). Systematic differences between methods were < 0.5 mm.
Conclusions Use of the VS leads to lower polyp size measurement variability and more uniform polyp sizing by individual endoscopists compared to visual and snare measurements.
High-quality Ge1−xSnx (x = 0–0.11) realized by UHV-CVD using Ge2H6 and SnCl4: Materials growth, structural/optical properties, and prototype IR photodetectors
Authors: Xie Changjiang , Li Yue , Wu Zhengjie , Wu Songsong , Wang Yixin , Lin Guangyang , Li Cheng , Cong Hui , Xu Chi , Xue Chunlai 
Published: July 2024

GeSn materials with Sn contents ranging between 0% and 11% have been successfully grown by using Ge2H6 and SnCl4 in a hot-wall UHV-CVD system at low reaction pressures of 0.2–0.4 Torr. Both fully strained and partially relaxed materials have been produced. It was found that the materials were of high crystallinity as evidenced by few threading dislocations from cross-sectional TEM. Photoluminescence studies have shown that the PL spectra shift to longer wavelengths, and the PL intensity increases exponentially as the Sn contents increase. The photoemission cutoff for a 9.5% Sn sample is beyond 2600 nm, and low temperature PL measurements have confirmed that this sample is already in the direct gap material regime. Prototype photoconductor devices were fabricated with a partially strained 5% Sn sample, showing much smaller dark currents and similar spectral coverage as compared to a fully strained 7.8% Sn device reported in the literature. The reported technical route has provided a new path toward high quality, low cost GeSn epitaxy, and will contribute to the development of group IV optoelectronics.
Simulating ultrafast transient absorption spectra from first principles using a time-dependent configuration interaction probe
Authors: Mehmood Arshad , Silfies Myles C. , Durden Andrew S. , Allison Thomas K. , Levine Benjamin G. 
Published: July 2024

Transient absorption spectroscopy (TAS) is among the most common ultrafast photochemical experiments, but its interpretation remains challenging. In this work, we present an efficient and robust method for simulating TAS signals from first principles. Excited-state absorption and stimulated emission (SE) signals are computed using time-dependent complete active space configuration interaction (TD-CASCI) simulations, leveraging the robustness of time-domain simulation to minimize electronic structure failure. We demonstrate our approach by simulating the TAS signal of 1′-hydroxy-2′-acetonapthone (HAN) from ab initio multiple spawning nonadiabatic molecular dynamics simulations. Our results are compared to gas-phase TAS data recorded from both jet-cooled (T ∼ 40 K) and hot (∼403 K) molecules via cavity-enhanced TAS (CE-TAS). Decomposition of the computed spectrum allows us to assign a rise in the SE signal to excited-state proton transfer and the ultimate decay of the signal to relaxation through a twisted conical intersection. The total cost of computing the observable signal (∼1700 graphics processing unit hours for ∼4 ns of electron dynamics) was markedly less than that of performing the ab initio multiple spawning calculations used to compute the underlying nonadiabatic dynamics.
Evaluating AI and human authorship quality in academic writing through physics essays
Authors: Yeadon Will , Agra Elise , Inyang Oto-Obong , Mackay Paul , Mizouri Arin 
Published: July 2024

Abstract
This study aims to compare the academic writing quality and detectability of authorship between human and AI-generated texts by evaluating n = 300 short-form physics essay submissions, equally divided between student work submitted before the introduction of ChatGPT and those generated by OpenAI’s GPT-4. In blinded evaluations conducted by five independent markers who were unaware of the origin of the essays, we observed no statistically significant differences in scores between essays authored by humans and those produced by AI (p-value = 0.107, α = 0.05). Additionally, when the markers subsequently attempted to identify the authorship of the essays on a 4-point Likert scale—from ‘Definitely AI’ to ‘Definitely Human’—their performance was only marginally better than random chance. This outcome not only underscores the convergence of AI and human authorship quality but also highlights the difficulty of discerning AI-generated content solely through human judgment. Furthermore, the effectiveness of five commercially available software tools for identifying essay authorship was evaluated. Among these, ZeroGPT was the most accurate, achieving a 98% accuracy rate and a precision score of 1.0 when its classifications were reduced to binary outcomes. This result is a source of potential optimism for maintaining assessment integrity. Finally, we propose that texts with ≤50% AI-generated content should be considered the upper limit for classification as human-authored, a boundary inclusive of a future with ubiquitous AI assistance whilst also respecting human-authorship.
Porous carbon materials with different dimensions and their applications in supercapacitors
Authors: Zhang Miao , Peng Zixin 
Published: July 2024

Abstract
Supercapacitors have become attractive energy storage devices due to their high power density, good cycling stability, and fast charging and discharging speeds. Porous carbon has great specific surface area, high energy density and good conversion performance, so porous carbon as supercapacitor electrode material has been widely concerned. Carbon materials with different dimensions and sizes, such as porous carbon spheres, porous carbon nanotubes, porous carbon nanofibers porous graphene and activated carbon can provide different performance advantages. At the same time, the composite of porous carbon with metal compounds, conductive polymers and particles containing N/P/O/S can further optimize electrode materials, as well as the significant effects on the increase of specific surface area and energy density are obtained. This article introduces the porous carbon materials used as electrode materials in recent years, as well as their multi-level structural materials and related composite materials. We first introduced porous carbon electrode materials with different dimensions and compared their electrochemical performance. Then, based on various research results, the factors affecting its electrochemical performance were discussed in detail. As well as, the preparation methods of porous carbon electrode materials were introduced, and the specific requirements, advantages and disadvantages of different preparation methods were briefly analyzed. The application of porous carbon electrode materials combined with other materials in supercapacitors is listed. Finally, a summary and outlook of the current research status were supplied, providing reference for the rational design of porous carbon supercapacitors in the future.
Optimal design of thick-walled circular coils for uniform magnetic field generation
Authors: Li Jialong , Zhu Xinhui , Sun Yuxuan , Cao Quanliang , Li Liang 
Published: July 2024

Abstract
Uniform magnetic field coils are widely used as electromagnetic equipment in industrial, medical, and research applications, with Helmholtz coils being a common configuration. For applications requiring a relatively high magnetic field (∼mT), Helmholtz coils typically feature a large coil cross-section. However, this characteristic makes them unsuitable for describing the magnetic field generated by a current loop model during the design process. In this work, we model the magnetic field of a large cross-section Helmholtz coil system, often referred to as a thick-walled Helmholtz coil. By employing a genetic algorithm, we transform the design problem of a Helmholtz coil into a constrained optimization problem. Subsequently, we propose a method for reverse designing a Helmholtz coil based on constraints on the target magnetic field. Finite element simulations verify the accuracy of the established magnetic field calculation model in describing the magnetic field generated by the thick-walled Helmholtz coil. Moreover, the designed Helmholtz coil effectively meets the design constraints and objectives. This method addresses the issue of significant errors in calculating the magnetic field and its uniformity resulting from the cross-sectional effect during the design of thick-walled Helmholtz coils. Furthermore, it satisfies the constraints for coil operating time and lightweight design.
Lattice dynamics and free energies of Fe–V alloys with thermal and chemical disorder
Authors: Diaz-Caraveo Cesar , C Bimal K , San Martín Jorge A Muñoz 
Published: July 2024

Abstract
Molecular dynamics simulations of Fe–V binary alloys with body-centered cubic as the underlying lattice were performed using a classical potential for chemically ordered and disordered states at finite temperatures for a common set of volumes. The equation of state was fitted to the computational data to obtain temperature- and chemical-order-dependent state functions via the Moruzzi-Janak-Schwarz approximation. Additionally, vibrational entropies that account for both thermal and chemical disorder were calculated for the equiatomic compositions from phonon density-of-states curves computed using effective force constants obtained from fits to the simulations. The latter predicts that the vibrational entropy at room temperature at equiatomicity is higher for the ordered phase than for the solid solution, a peculiar behavior previously observed experimentally. The internal energy of mixing favors ordering at all compositions, with a maximum at equiatomicity that decreases as the solute concentration decreases. The configurational entropy contribution to the free energy of mixing is almost entirely responsible for the stability of the high-temperature disordered phase.
Dynamic analysis of planetary gear transmission based on Lagrange interpolation polynomials
Authors: Chen Ronghua , Gu Yingkui , Qiu Guangqi , Huang Peng 
Published: July 2024

Abstract
This paper proposes a novel dynamic model considering manufacturing errors and eccentricity errors to analyze the dynamics of planetary gear transmission (PGT). The dynamic model is established based on the fractional-order calculus and solved by an enhanced fourth-order Lagrange interpolation polynomials method. Three numerical examples and the vibration experiments of PGT are employed for verification. The comparison results indicate that the proposed solution method has higher solution accuracy and efficient than the existing algorithms in solving fractional equations, and the relative errors of the proposed solution method in three examples are 0.32%, 0.78% and 0.16%, respectively. The proposed dynamic model of PGT has better agreement with the experimentally measured signal compared with the integer-order dynamic model, and the maximum error and average error of the characteristic frequency amplitude between the proposed dynamic model and the measured signal are 4.76% and 3.57%, respectively. The proposed method contributes to the theoretical foundation for the signal monitoring of PGT.
Turbulence closure modeling with machine learning: a foundational physics perspective
Authors: Girimaji Sharath S 
Published: July 2024

Abstract
Turbulence closure modeling using machine learning (ML) is at an early crossroads. The extraordinary success of ML in a variety of challenging fields had given rise to an expectation of similar transformative advances in the area of turbulence closure modeling. However, by most accounts, the current rate of progress toward accurate and predictive ML-RANS (Reynolds Averaged Navier–Stokes) closure models has been very slow. Upon retrospection, the absence of rapid transformative progress can be attributed to two factors: the underestimation of the intricacies of turbulence modeling and the overestimation of ML’s ability to capture all features without employing targeted strategies. To pave the way for more meaningful ML closures tailored to address the nuances of turbulence, this article seeks to review the foundational flow physics to assess the challenges in the context of data-driven approaches. Revisiting analogies with statistical mechanics and stochastic systems, the key physical complexities and mathematical limitations are explicated. It is noted that the current ML approaches do not systematically address the inherent limitations of a statistical approach or the inadequacies of the mathematical forms of closure expressions. The study underscores the drawbacks of supervised learning-based closures and stresses the importance of a more discerning ML modeling framework. As ML methods evolve (which is happening at a rapid pace) and our understanding of the turbulence phenomenon improves, the inferences expressed here should be suitably modified.
Flat bands in three-dimensional lattice models with non-trivial Hopf index
Authors: Dutta Ivan , Saha Kush 
Published: July 2024

Abstract
We report the presence of exactly and nearly flat bands with non-trivial topology in three-dimensional (3D) lattice models. We first show that an exactly flat band can be realized in a 3D lattice model characterized by a 3D topological invariant, namely Hopf invariant. In contrast, we find another distinct 3D model, exhibiting both 2D Chern and 3D Hopf invariant, namely Hopf-Chern insulator, that can host nearly or perfect flat bands across different 2D planes. Such a Hopf-Chern model can be constructed by introducing specific hopping along the orthogonal direction of a simple two-orbital 2D Chern insulator in the presence of in-plane nearest-neighbor and next-nearest hopping among different orbitals. While the Chern planes host nearly perfect flat bands, the orthogonal planes can host both perfect or nearly perfect flat bands with zero Chern number at some special parameter values. Interestingly, such a 3D lattice construction from 2D allows finite Hopf invariant too. Finally, we show that higher Chern models can also be constructed in the same lattice setup with only nearest and next-nearest hopping, but the appearance of flat bands along high-symmetric path in the Brillouin zone requires longer-range hopping. We close with a discussion on possible experimental platforms to realize the models.
Detection of breast tumor with a frequency selective surface loaded ultra-wide band antenna system
Authors: Ullah Naveed , Abdulkarim Yadgar I , Wang Fang , Liu Yuhuai , Zerrad Fatima-Ezzahra , Taouzari Mohamed 
Published: July 2024

Abstract
Breast tumors are a significant cause to the global death rate among women. However, the fatality rate can be lowered through early detection. This paper presents an ultra-wideband, modified patch antenna of a compact size that can be used for microwave-sensing biomedical applications in the detection of breast cancer. A partial ground plane and slots are implemented in a transformed patch antenna to enhance the impedance bandwidth. The antenna is backed by a uniform frequency selective surface of 5 × 5 unit cells to achieve the necessary antenna characteristics, specifically directivity and gain, for microwave detection applications. Through optimization and fabrication, the final design maintained (|S11|< −10 dB) over the entire frequency band of 11.6 GHz (3.1–14.7 GHz) and achieved an average gain of over 5 dBi. Other metrics, such as group delay and the fidelity factor in different setups, are also simulated to observe the expected performance in the required frequency range. Finally, based on simulation, a model is suggested that comprises various configurations of antenna arrays, including one Tx antenna and one to seven Rx antennas. Further, breast phantom with different tumor sizes and locations were used in the simulation. The simulation results successfully validated the detection of breast cancer cells. We believe these technologies can open possibilities in healthcare applications for identifying tumors.
Physics informed neural network based scheme and its error analysis for ψ-Caputo type fractional differential equations
Authors: Sivalingam S M , Govindaraj V 
Published: July 2024

Abstract
This paper proposes a scientific machine learning approach based on Deep Physics Informed Neural Network (PINN) to solve ψ-Caputo-type differential equations. The trial solution is constructed based on the Theory of Functional Connection (TFC), and the loss function is built using the L1-based difference and quadrature rule. The learning is handled using the new hybrid average subtraction, standard deviation-based optimizer, and the nonlinear least squares approach. The training error is theoretically obtained, and the generalization error is derived in terms of training error. Numerical experiments are performed to validate the proposed approach. We also validate our scheme on the SIR model.
Advances and challenges in 4H silicon carbide: defects and impurities
Authors: Yang Yanwei , Tong Zhouyu , Pi Xiaodong , Yang Deren , Huang Yuanchao 
Published: July 2024

Abstract
Under the impetus of global carbon peak and carbon neutrality goals, a new generation of semiconductor material is urgently needed in various aspects of power electronic systems. In comparison to traditional semiconductor materials like single-crystal silicon, the outstanding characteristics of 4H silicon carbide (4H-SiC) have gradually positioned it as a crucial semiconductor material for emerging power semiconductor applications. Attributed to the significance of impurities and defects in the semiconductor, profound and in-depth comprehension of impurities and defects about 4H-SiC plays a crucial guiding role. This paper, building upon a brief overview of the current state of 4H-SiC research, summarizes the experimental and theoretical advancements in the study of defects and impurities about 4H-SiC in recent years. Besides, we also systematically review the categories of defects in 4H-SiC, introduce methods for characterizing and identifying defects in 4H-SiC, and thoroughly discuss potential doping technologies in 4H-SiC. Challenges faced in the research of defects and impurities are finally outlined.
Studies of anisotropic polarization in graphene oxide doped in PVA
Authors: A Athira , Shaji Chitra , Ramachandran Neeraj , Sharan Alok 
Published: July 2024

Abstract
We have observed and measured the optical anisotropy of graphene oxide (GO) in polyvinyl alcohol (PVA) using Stokes-Mueller Polarimetry (SMP). We found that it depends on the films with varying weight percent of GO in PVA. Analysis of polarized light transmitted through the ordered microstructure of GO in PVA reveals the anisotropic behavior due to its preferential alignment. The complex refractive index analysis of GO-PVA films complements the results of SMP.
EPR steering paradox ‘2
Q
= (2−δ)
C
’
Authors: Liu Zhi-Jie , Fan Xing-Yan , Zhou Jie , Xie Mi , Chen Jing-Ling 
Published: July 2024

Abstract
Einstein-Podolsky-Rosen (EPR) steering is a quantum nonlocality between entanglement and Bell’s nonlocality emphasizing the incompatibility of the local-hidden-state (LHS) model with quantum theory. It is well established that the EPR steering paradox is an essential method for determining steering, which reveals the nature of steering by logical contradiction. However, previous studies on the EPR steering paradox have only examined cases where the conditional states of the steered party are pure. In this work, we present the EPR steering paradox about the case when the conditional states of the steered party are mixed, which can be expressed as a paradoxical equality ‘

2

Q

=

2
−
δ

C

’

0
<
δ
<
1

given by quantum (Q) and classical (C) theories. For any N-qubit state, in the two-setting steering protocol, the contradiction ‘

2

Q

=

2
−
δ

C

’ can be obtained if and only if a particular set of projective measurements of the steering party makes all the conditional states of the steered party pure, which also implies that the N-qubit state is steerable. Moreover, considering the conditional states of the steered party as mixed states, we are able to identify the full range of steerable states detectable through the EPR steering paradox method. This also means that, so far, one has found all the steerable states that can be recognized by the EPR steering paradox, which is significant for some typical quantum schemes such as quantum teleportation and quantum key distribution.
Electromagnetic wave scattering in plasma beam-driven waveguides under strong magnetic fields
Authors: Rizvi Shahana , Afzal Muhammad 
Published: July 2024

Abstract
This study analyzes the scattering of electromagnetic waves in a cold and uniform plasma-filled waveguide driven by an intense relativistic plasma beam under a strong magnetic field. The strong interaction of plasma with electromagnetic waves enables its potential use in different types of waveguides. The Helmholtz equation governs the boundary value problem, which is solved by incorporating the mode matching technique. Invoking the boundary and matching conditions and the derived orthogonality and dispersion relations in this scheme gives an exact solution to the scattering problem. The numerical results shed light on the occurrence of reflection and transmission and flow of power. The power flux is plotted against angular frequency and various duct configurations. The solution is completely validated through the benefit of analytical and numerical results. The investigation of this structure reveals not only its mathematical, but also its physical features.