bluuebunny/crossref_metadata_2025_split huggingface dataset:
The weak gravity conjecture, overcharged shells and gravitational traps
Authors: Kehagias Alex , Kokkotas Kostas D , Riotto Antonio , Taskas John , Tringas George 
Published: February 2024

AbstractThe Weak Gravity Conjecture (WGC) predicts that in quantum gravity there should exist overcharged states, that is states with charge larger than their mass. Extending this to large masses and charges, we are expecting similar overcharged classical solutions. This has been demonstrated in higher-derivative extensions of General Relativity. In this paper we investigate the existence of overcharged solutions in General Relativity. We study the dynamics of a thin shell of massmand chargeQunder the action of its own gravitational andU(1) fields. We show that shells with surface energyσand pressurePobeyingP=wσwith0⩽w⩽1are necessarily underchargedm⩾|Q|and always collapse to form Reissner–Nordström black holes. Nevertheless, if−1⩽w<0, we find that overchargedm⩽|Q|shells exist, which however, are inevitably stabilized at finite radial distance. Therefore they never form naked singularities in accordance with cosmic censorship and the conjectured relation between cosmic censorship and the WGC. An intriguing consequence of the existence of such overcharged shells is that gravitational modes may form bound states due to the peculiar form of the Regge–Wheeler–Zerilli potential. This might lead to gravitational traps close the surface of near-overcharged shells.
Efficient kernel canonical correlation analysis using Nyström approximation
Authors: Fang Qin , Shi Lei , Xu Min , Zhou Ding-Xuan 
Published: February 2024

Abstract
The main contribution of this paper is the derivation of non-asymptotic convergence rates for Nyström kernel canonical correlation analysis (CCA) in a setting of statistical learning. Our theoretical results reveal that, under certain conditions, Nyström kernel CCA can achieve a convergence rate comparable to that of the standard kernel CCA, while offering significant computational savings. This finding has important implications for the practical application of kernel CCA, particularly in scenarios where computational efficiency is crucial. Numerical experiments are provided to demonstrate the effectiveness of Nyström kernel CCA.
Energy loss of heavy quarks in the presence of magnetic field
Authors: Jamal Mohammad Yousuf , Prakash Jai , Nilima Indrani , Bandyopadhyay Aritra 
Published: February 2024

Abstract
We study the heavy quark energy loss in the presence of a background magnetic field. The analysis considers the high magnetic field generated by spectators from initial hard collisions that were incorporated using the medium-modified Debye mass, determined from quark condensates at finite temperature and magnetic field via recent lattice quantum chromodynamics calculations. We analyse the impact of medium polarization on the heavy quark propagation in a quark–gluon plasma formed in relativistic heavy-ion colliders like relativistic heavy ion collider and large hadron collider. For simplification, we considered the static medium with constant temperature and magnetic field values. Then, we explore the nuclear modification factor (R
AA) at different magnitudes of magnetic field strengths at fixed temperatures. The energy loss of heavy quarks significantly increases, leading to R
AA suppression at higher magnetic field values.
A novel laser-induced fluorescence concept for thermometry measurements in machining lubricoolants
Authors: Koegl Matthias , Glahn Jake , Zigan Lars 
Published: February 2024

Abstract
This study investigates a two-colour laser-induced fluorescence (LIF) technique for thermometry in cooling lubricants (CL) for machining. The diagnostic technique should enable a simultaneous determination of cooling film thickness and film temperature, which is relevant for typical machining processes like turning and milling processes. The temperature determination is based on a temperature-sensitive fluorescence intensity ratio of a special dye determined in suitable spectral regions representing common band pass filters. For this purpose, two CL emulsions CL6 (6 vol.% CL, 94 vol.% water; normal machining) and CL10 (10 vol.% CL, 90 vol.% water; heavy machining) and its individual components were doped with the fluorescence dye Eosin-Y. Temperature dependent spectral LIF intensities were recorded in the range of 273–313 K, which are relevant for milling and cutting operations. Furthermore, absorption spectra were analysed as well. The temperature-dependent fluorescence measurements revealed a temperature limit for the emulsion stability. The emission peaks of Eosin-Y are shifted with increasing temperature towards longer wavelengths. The sensitivities of CL10 (1.88%/K) and CL6 (1.58%/K) are comparable to or even higher than the sensitivities of other LIF dyes provided in the literature. The literature-based dyes were however not determined in those CL. The measurements showed, that the investigated tracer-CL/water emulsions mixed with the dye enable a reliable temperature determination.
Contactless weighing method based on deep learning and acoustic levitation
Authors: Wang Yingwei , Jiang Liangxu , Chen Ziyi , Zhang Han , Li Xinbo 
Published: February 2024

Abstract
Acoustic weighing is a promising contactless method for screening the mass of micro-nano objects as it avoids contact contamination and losses. Existing acoustic weighing methods determine the mass of an object by detecting its oscillation trajectory with a laser sensor. However, this method suffers from several limitations, such as short measurement distance, poor accuracy in measuring transparent objects, and inducing damage to photosensitive samples. To solve these issues, this work proposes a contactless weighing method based on location-aware neural network (LANet) and acoustic levitation. The proposed LANet is a deep learning-based image processing method that detects object bit oscillation trajectories completely contactless, regardless of the color, shape, and oscillation distance of the levitated object. We employ a cross-stage aggregation module and cross-mixed feature pyramid strategy to build LANet network depth for enhanced feature extraction. In addition, to create a contactless environment, we built an acoustic levitation system, which drives the oscillation of objects. Finally, we verified the accuracy and effectiveness of the method. The results show that the proposed network can accurately detect the oscillation trajectories of various objects with high detection performance, even for small objects in low-contrast backgrounds. Meanwhile, the proposed method can accurately measure the mass of objects with a percentage error of no more than 7.83%.
Interface modification for efficient carbon-electrode CsPbI2Br perovskite solar cells using ionic liquid
Authors: Zhang Yaping , Wang Tao , Wang Yanan , Chen Jing , Peng Lin , Liu Xiaolin , Lin Jia 
Published: February 2024

Abstract
All-inorganic CsPbI2Br, as a promising photovoltaic (PV) material, have attracted extensive research attention in society for its outstanding thermal stability and appropriate trade-offs. Carbon-based perovskite solar cells (C-PSCs) without hole transporting layer (HTL) have shown great potential in terms of cost-effectiveness and stability. However, the inevitable defects on the surface of CsPbI2Br films severely hampers the development of high-efficiency CsPbI2Br C-PSCs. Surface engineering has emerged an effective approach to overcome this challenge. Herein, 1-decyl-3-methylimidazolium tetrafluoroborate (DMTT) ionic liquid was introduced between CsPbI2Br and carbon electrode to reduce non-recombination of charges, decrease defect states, minimize the energy-level mismatch, and greatly enhance the device stability. As a result, the HTL-free CsPbI2Br C-PSCs combined with DMTT as an interface modification achieved a higher power conversion efficiency (PCE) of 12.47% than that of the control devices with a PCE of 11.32%. Furthermore, without any encapsulation, the DMTT-optimized C-PSC remained approximately 84% of its initial PCE after over 700 h under room temperature and 25% relative humidity (RH) conditions. Additionally, when exposed to a temperature of 65 °C for over 400 h, the device still retained 74% of the initial PCE, demonstrating its thermal stability.
Single-mode nanolasers based on FP-WGM hybrid cavity coupling
Authors: Ullah Salman , Zhuge Minghua , Zhang Liang , Fu Xiang , Ma Yaoguang , Yang Qing 
Published: February 2024

Abstract
As an idealized light source, semiconductor nanowire (NW) lasers have been extensively studied due to its potential applications in many fields such as optoelectronics, nanophononics, optical communication, signal processing, and displays. In this letter, we proposed a novel approach to realize a single-mode nanolaser by forming an Fabry–Perot whispering gallery mode (FP-WGM) hybrid nanocavity between two cross-contact CdS NWs, i.e. x and y-NW. In our method, x-NW supports the regular FP oscillation in the axis direction while the cross section of y-NW provides a ultrasmall WGM nanocavity with a higher Q-factor and mode election which confirms the specific single mode can be excited. Experimentally, single-mode lasing emission centered at 517 nm was obtained with full width at half maximum of 0.08 nm and lasing threshold of ∼50 kW cm−2. The suggested designing skills projected a general strategy for lasing mode regulation and single-mode realization. The single-mode low-threshold lasing strategy in coupled NWs may open a new avenue for practical applications of NW lasers and further trigger other photonic devices at a visible range.
Enhancing control in spatial atomic layer deposition: insights into precursor diffusion, geometric parameters, and CVD mitigation strategies
Authors: Nguyen Thien Thanh , Nguyen Thi Kieu Diem , Bui Hao Van , Le Thi Ngoc Loan , Nguyen Viet Huong 
Published: February 2024

Abstract
In recent years, spatial atomic layer deposition (SALD) has gained significant attention for its remarkable capability to accelerate ALD growth by several orders of magnitude compared to conventional ALD, all while operating at atmospheric pressure. Nevertheless, the persistent challenge of inadvertent contributions from chemical vapor deposition (CVD) in SALD processes continues to impede control over film homogeneity, and properties. This research underscores the often-overlooked influence of diffusion coefficients and important geometric parameters on the close-proximity SALD growth patterns. We introduce comprehensive physical models complemented by finite element method simulations for fluid dynamics to elucidate SALD growth kinetics across diverse scenarios. Our experimental findings, in alignment with theoretical models, reveal distinctive growth rate trends in ZnO and SnO2 films as a function of the deposition gap. These trends are ascribed to precursor diffusion effects within the SALD system. Notably, a reduced deposition gap proves advantageous for both diffusive and low-volatility bulky precursors, minimizing CVD contributions while enhancing precursor chemisorption kinetics. However, in cases involving highly diffusive precursors, a deposition gap of less than 100 μm becomes imperative, posing technical challenges for large-scale applications. This can be ameliorated by strategically adjusting the separation distance between reactive gas outlets to mitigate CVD contributions, which in turn leads to a longer deposition time. Furthermore, we discuss the consequential impact on material properties and propose a strategy to optimize the injection head to control the ALD/CVD growth mode.
A 3D kinetic Monte Carlo study of streamer discharges in
CO2
Authors: Marskar R 
Published: February 2024

Abstract
We theoretically study the inception and propagation of positive and negative streamers in

C

O

2

. Our study is done in 3D, using a newly formulated kinetic Monte Carlo discharge model where the electrons are described as drifting and diffusing particles that adhere to the local field approximation. Our emphasis lies on electron attachment and photoionization. For negative streamers we find that dissociative attachment in the streamer channels leads to appearance of localized segments of increased electric fields, while an analogous feature is not observed for positive-polarity discharges. Positive streamers, unlike negative streamers, require free electrons ahead of them in order to propagate. In

C

O

2

, just as in air, these electrons are supplied through photoionization. However, ionizing radiation in

C

O

2

is absorbed quite rapidly and is also weaker than in air, which has important ramifications for the emerging positive streamer morphology (radius, velocity, and fields). We perform a computational analysis which shows that positive streamers can propagate due to photoionization in

C

O

2

. Conversely, photoionization has no effect on negative streamer fronts, but plays a major role in the coupling between negative streamers and the cathode. Photoionization in

C

O

2

is therefore important for the propagation of both positive and negative streamers. Our results are relevant in several applications, e.g.

C

O

2

conversion and high-voltage technology (where

C

O

2

is used in pure form or admixed with other gases).
Potential design strategy of wide-bandgap semiconductor p-type β-Ga2O3
Authors: Liu Xinglin , Huang Jun , Wei Qiangmin , Ye Lei 
Published: February 2024

Abstract
Wide bandgap semiconductor gallium oxide (β-Ga2O3) has emerged as a prominent material in the field of high-power microelectronics and optoelectronics, due to its excellent and stable performance. However, the lack of high-quality p-type β-Ga2O3 hinders the realization of its full potential. Here, we initially summarize the origins of p-type doping limitation in β-Ga2O3, followed by proposing four potential design strategies to enhance the p-type conductivity of β-Ga2O3. (i) Lowering the formation energy of acceptors to enhance its effective doping concentration. (ii) Reducing the ionization energy of acceptors to increase the concentration of free holes in the valence band maximum (VBM). (iii) Increasing the VBM of β-Ga2O3 to decrease the ionization energy of acceptors. (iv) Intrinsic defect engineering and nanotechnology of β-Ga2O3. For each strategy, we illustrate the design principles based on fundamental physical theories along with specific examples. From this review, one could learn the p-type doping strategies for β-Ga2O3.
Low-voltage operating, high mobility top-gate structural flexible organic thin-film transistor with a one-step spin-coated binary polymer gate dielectric
Authors: Su Jing , Yan Zhenxiang , Lin Yijie , Xie Wenfa , Wang Wei 
Published: February 2024

Abstract
Low-voltage operation is one of the prerequisites for the practical applications of the organic thin-film transistors (OTFTs). Up to date, the most reported low-voltage operatable OTFTs use a bottom-gate structure, and are fabricated by several different technologies in the whole process, in which the organic semiconductors and/or gate dielectrics are prepared in the expensive vacuum equipment. The simple fabricating technologies and fewer processes can better demonstrate the inherent advantages, and enhance the commercial competitiveness of OTFTs. Here, we propose a strategy to fabricate the binary polymers gate dielectric by one-step spin-coating in the top-gate structured flexible OTFTs, by which not only the device performances are prominently improved, but also the fabricating process of the OTFTs is minimized. As a result, the flexible OTFTs exhibit a high mobility over 0.5 cm2 Vs−1, low threshold voltage near to −0.5 V, and excellent mechanical bending durability with a very slightly performances degradation after the tensile and compressive bending at a small curvature radius of 3.0 mm over 1000 cycles.
Exploring exact solutions for physical differential models through generalized derivatives
Authors: Hyder Abd-Allah , Barakat Mohamed A , Soliman Ahmed H , Almoneef Areej A 
Published: February 2024

Abstract
In this study, we develop three well-known fractional differential physical models with novel exact solutions. Liouville, Dodd-Bullough-Mikhailov (DBM), and Sinh-Gordon equations are the models under consideration. These models will be broken down into three nonlinear ordinary differential equations using a waveform transformation, which can be precisely solved using the approach of the simplest equation method. The suggested method is applicable to several categories of nonlinear physical models and allows us to extract numerous generalized solutions in soliton and periodic forms The resulting solutions may also be directly compared with a number of findings obtained in the literature. Additionally, representations in two and three dimensions are provided to show how changing the fractional parameter’s amount may impact how monotonic the solutions are obtained.
Dynamic switching: vanadium dioxide and graphene-based terahertz perfect absorber for tunable broadband absorption and tri-band absorption
Authors: Liu Fangfang , Qi Yunping , Wang Li , Wen Yujiao , Wang Xiangxian 
Published: February 2024

Abstract
In this paper, a dual-function switchable perfect absorber in the terahertz band is simulated and proposed. The design leverages the phase transition properties of vanadium dioxide (VO2) and the dynamically tunable properties of graphene. The absorber exhibits broadband absorption when VO2 is operated in the insulating state alone, with a bandwidth of 7.09 THz and a high modulation depth of 99.45% resulting in absorption levels above 90%. Additionally, by operating the graphene square ring and the graphene round ring at the Fermi levels of 0.72 eV and 0.75 eV, respectively, the absorber demonstrates tri-band absorption, making it suitable for refractive index sensing applications. The absorber’s operating frequency can be easily tuned by adjusting the conductivity of VO2 and the Fermi levels of graphene, enabling dynamic tunability. The feasibility of our work positions it as a promising candidate for designing switchable broadband and multi-band absorbers. Consequently, our research holds significant potential for applications in terahertz devices.
Theory of Burstein-Moss effect in semiconductors with anisotropic energy bands
Authors: Ivchenko Vladimir 
Published: February 2024

Abstract
We study the peculiarities of the Burstein–Moss shift employing two-band model with an anisotropic valence band. There is a long wave tail which has a convex or concave shape depending on the ratio between the longitudinal and transverse hole masses. The width of this anisotropy-induced tail is temperature-independent and increases with increasing electron concentration and difference between the hole masses. This width also does not depend upon the value of the energy gap. Having experimentally evaluated the tail width and the position of the break in the optical absorption curve, one can deduce the values of the reduced hole masses.
Analysis of bioprinting strategies for skin diseases and injuries through structural and temporal dynamics: historical perspectives, research hotspots, and emerging trends
Authors: Teng Fei , Wang Wei , Wang Zhi-Qiang , Wang Gui-Xue 
Published: February 2024

Abstract
This study endeavors to investigate the progression, research focal points, and budding trends in the realm of skin bioprinting over the past decade from a structural and temporal dynamics standpoint. Scholarly articles on skin bioprinting were obtained from WoSCC. A series of bibliometric tools comprising R software, CiteSpace, HistCite, and an alluvial generator were employed to discern historical characteristics, evolution of active topics, and upcoming tendencies in the area of skin bioprinting. Over the past decade, there has been a consistent rise in research interest in skin bioprinting, accompanied by an extensive array of meaningful scientific collaborations. Concurrently, diverse dynamic topics have emerged during various periods, as substantiated by an aggregate of 22 disciplines, 74 keywords, and 187 references demonstrating citation bursts. Four burgeoning research subfields were discerned through keyword clustering—namely, #3 ‘in situ bioprinting’, #6 ‘vascular’, #7 ‘xanthan gum’, and #8 ‘collagen hydrogels’. The keyword alluvial map reveals that Module 1, including ‘transplantation’ etc, has primarily dominated the research module over the previous decade, maintaining enduring relevance despite annual shifts in keyword focus. Additionally, we mapped out the top six key modules from 2023 being ‘silk fibroin nanofiber’, ‘system’, ‘ionic liquid’, ‘mechanism’, and ‘foot ulcer’. Three recent research subdivisions were identified via timeline visualization of references, particularly Clusters #0 ‘wound healing’, #4 ‘situ mineralization’, and #5 ‘3D bioprinter’. Insights derived from bibliometric analyses illustrate present conditions and trends in skin bioprinting research, potentially aiding researchers in pinpointing central themes and pioneering novel investigative approaches in this field.
Disentangling the reasons why older adults do not readily participate in cancer trials: a socio-epidemiological mixed methods approach
Authors: Hagège Meoïn , Bringuier Michaël , Martinez-Tapia Claudia , Chouaïd Christos , Helissey Carole , Brain Etienne , Lempdes Godelieve Rochette , Dubot Coraline , Bello-Roufai Diana , Geiss Romain , Kempf Emmanuelle , Gourden Audrey , Elgharbi Hanane , Garrigou Sonia , Gregoire Laetitia , Derbez Benjamin , Canouï-Poitrine Florence 
Published: February 2024

Abstract

Background
Few studies of the under-representation of older adults in cancer clinical trials (CTs) have encompassed the entire pathway from a trial being available in a cancer centre to the patient’s invitation to participate and then agreement or refusal to participate.

Objectives
The study’s primary objective was to evaluate CT non-invitation and refusal rates. The secondary objectives were to identify factors associated with non-invitation and refusal and to assess experiences of CT participation from the patients’ and professionals’ perspectives.

Methods
Here, we used mixed methods and a socio-epidemiological approach to analyse reasons for the non-participation of eligible older patients with a solid cancer in cancer CTs in France.

Results
We found that non-invitation and low CT participation are mainly related to the patients’ sociodemographic characteristics and living conditions (such as social isolation, being single, divorced or widowed, not having children and the absence of close family members) and the healthcare professionals’ perceptions of insufficient informal support or a high homecare requirement.

Conclusion
Our results suggest that efforts to increase fair inclusion and the participation of older adults in CTs should target the physician–patient relationship, the medical profession and hospital funding, rather than the patient alone.