bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface plasmon coupling effects on the förster resonance energy transfer from quantum dot into rhodamine 6G
Authors: Chen Chien-Yu , Ni Chia-Chun , Wu Ruei-Nan , Kuo Sheng-Yang , Li Chia-Hao , Kiang Yean-Woei , Yang C C 
Published: April 2021

Abstract
Rhodamine 6G (R6G) molecules linked CdZnSeS/ZnS green-emitting quantum dots (QDs) are self-assembled onto Ag nanoparticles (NPs) for studying the surface plasmon (SP) coupling effect on the Förster resonance energy transfer (FRET) process from QD into R6G. SP coupling can enhance the emission efficiency of QD such that FRET has to compete with QD emission for transferring energy into R6G. It is found that FRET efficiency is reduced under the SP coupling condition. Although R6G emission efficiency can also be enhanced through SP coupling when it is directly linked onto Ag NP, the enhancement decreases when R6G is linked onto QD and then the QD-R6G complex is self-assembled onto Ag NP. In particular, R6G emission efficiency can be reduced through SP coupling when the number of R6G molecules linked onto a QD is high. A rate-equation model is built for resembling the measured photoluminescence decay profiles and providing us with more detailed explanations for the observed FRET and SP coupling behaviors.
MoS2/WSe2 nanohybrids for flexible paper-based photodetectors
Authors: Pataniya Pratik M , Patel Vikas , Sumesh C K 
Published: April 2021

Abstract
Flexible photodetectors functionalized by transition metal dichalcogenides have attracted great attention due to their excellent photo-harvesting efficiency. However, the field of optoelectronics still requires advancement in the production of large-area, broad band and flexible photodetectors. Here we report a flexible, stable, broad band and fast photodetector based on a MoS2/WSe2 heterostructure on ordinary photocopy paper with pencil-drawn graphite electrodes. Ultrathin MoS2/WSe2 nanohybrids have been synthesized by an ultrahigh yield liquid-phase exfoliation technique. The thin sheets of WSe2, and MoS2 contain two to four layers with a highly c-oriented crystalline structure. Subsequently, the photodetector was exploited under ultra-broad spectral range from 400 to 780 nm. The photodetector exhibits excellent figure of merit such as on/off ratio of the order of 103, photoresponsivity of 124 mA W−1 and external quantum efficiency of 23.1%. Encouragingly, rise/decay time of about 0.1/0.3 s was realized, which is better than in previous reports on paper-based devices.
Cerebrovascular tone and resistance measures differ between healthy control and patients with acute intracerebral haemorrhage: exploratory analyses from the BREATHE-ICH study
Authors: Ince Jonathan , Mankoo Alex S , Kadicheeni Meeriam , Swienton David , Panerai Ronney B , Robinson Thompson G , Minhas Jatinder S 
Published: April 2021

Abstract

Objective. Cerebral autoregulation impairment in acute neurovascular disease is well described. The recent BREATHE-ICH study demonstrated improvements in dynamic cerebral autoregulation, by hypocapnia generated by hyperventilation, in the acute period following intracranial haemorrhage (ICH). This exploratory analysis of the BREATHE-ICH dataset aims to examine the differences in hypocapnic responses between healthy controls and patients with ICH, and determine whether haemodynamic indices differ between baseline and hypocapnic states. Approach. Acute ICH patients were recruited within 48 h of onset and healthy volunteers were recruited from a university setting. Transcranial Doppler measurements of the middle cerebral artery were obtained at baseline and then a hyperventilation intervention was used to induce hypocapnia. Patients with ICH were then followed up at 10–14 D post-event for repeated measurements. Main results. Data from 43 healthy controls and 12 patients with acute ICH met the criteria for statistical analysis. In both normocapnic and hypocapnic conditions, significantly higher critical closing pressure and resistance area product were observed in patients with ICH. Furthermore, critical closing pressure changes were observed to be sustained at 10–14 D follow up. During both the normocapnic and hypocapnic states, reduced autoregulation index was observed bilaterally in patients with ICH, compared to healthy controls. Significance. Whilst this exploratory analysis was limited by a small, non-age matched sample, significant differences between ICH patients and healthy controls were observed in factors associated with cerebrovascular tone and resistance. These differences suggest underlying cerebral autoregulation changes in ICH, which may play a pivotal role in the morbidity and mortality associated with ICH.
Influence of coverage of fin-shaped rods on flow-induced vibration and power extraction of cylinder-based wind energy harvester
Authors: Zou Qunfeng , Ding Lin , Song Tian , Yang Lin , Zhang Li 
Published: April 2021

Abstract
Wind-induced vibration (WIV) and power extraction performances of a circular cylinder with symmetrically installed fin-shaped rods (FSR) were experimentally and numerically investigated under different coverages. The FSR coverage which is expressed as an angle (α) is measured from the upstream edge to the downstream edge of the rod. The effect of FSR installation angle (θ) which is the angle from the stagnation point of cylinder to the upstream edge of the rod was also considered in this work. The FSR cylinder is exposed in uniform wind and allowed to vibrate in cross-flow direction. The output electric power is realized by piezoelectric patch. It is found that, for most cases, the output power of FSR cylinder increases monotonously with the rise of α for a given wind velocity (U). In addition, the tendency of output voltage varies with the wind velocity is highly similar to that of output power. The maximum values of output voltage and power are 19.70 V and 1.90 mW can be obtained when α= 20° (θ= 60°). The WIV responses of FSR cylinder show that the amplitudes of FSR cylinder increase with the rise of α for low installation angle (θ= 0°, 30°) and the maximum amplitudes exceed 2D (D: diameter of circular cylinder) can be observed for α= 40°/50° (θ= 30°) and α= 20° (θ= 60°). The reduced frequency of cylinder for θ= 0° and 30° does not sensitive to the coverage (α). It is worth noting that multiple frequencies can be captured for high coverage. Due to the boundary layer separating point moves in downstream direction with the increase of U and α, the vortex pattern switches from 2S to 2P.
The simulation of plasma in magnetic conical-cusp mirrors using COMSOL multiphysics
Authors: Ghanbari M R 
Published: April 2021

Abstract
In nuclear fusion plasma, open magnetic systems have advantages, including high beta, no neoclassical radial transport, ease preservation, and upgrades. Magnetic Conical-Cusp Mirror is one of these systems that has attracted the attention of researchers. In the Conical-Cusp Mirror device, plasma is confined by various magnetic coils with different current directions. In this work, a Conical-Cusp Mirror plasma system and a simple magnetic mirror plasma were simulated by COMSOL Multiphysics. Moreover, magnetic field gradient and plasma beta were compared in these two systems. The results showed that the Conical-Cusp Mirror plasma is more stable and has higher beta.
Investigation of Debye temperature and thermal disorder in Fe-Cr intermetallic alloys
Authors: Thi Hong Nguyen , Khac Hieu Ho 
Published: April 2021

Abstract
In this work, we have developed the anharmonic Debye model to study the Debye temperature and thermal disorder in Fe-Cr intermetallic alloys. The analytical expressions of the anharmonic effective potential, the effective force constant, the Debye temperature and corresponding frequency, and the atomic mean-square displacement characterizing the Debye-Waller factor have been derived. We have implemented the numerical calculations for Fe-Cr intermetallic systems with various Cr concentration up to temperature 700 K. Our results show that the Debye temperature of Fe-Cr systems increases gradually with the increasing Cr composition. Reversely, the mean-square displacement curve drops gradually with Cr concentration. These effects can be explained by the weaker coupling force between Fe atoms as compared to the Cr atoms. Furthermore, we also show the important contributions of thermal disorder to mean-square displacement at high temperature due to thermal lattice vibrations.
Spontaneous symmetry breaking in the phase space
Authors: Contoyiannis Y , Stavrinides S G , Kampitakis M , Hanias M P , Potirakis S M , Papadopoulos P 
Published: April 2021

Abstract
In this brief, the spontaneous symmetry breaking (SSB) of the

φ

4

theory in phase space, is studied. This phase space results from the appropriate system of Poincaré maps, produced in both the Minkowski and the Euclidean time. The importance of discretization in the creation of phase space, is highlighted. A series of interesting, novel, unknown behaviors are reported for the first time; among them the most characteristic is the change in stability. In specific, the stable fixed points of the

φ

4

potential appear as unstable ones, in phase space. Additionally, in the Euclidean-time phase space a unique instability in the position of the critical point, can be created. This instability is further proposed to host tachyonic field in Euclidean space.
Optical trapping SiO2 nanoparticles based on liquid-core metal-cladding waveguide
Authors: Jin Yonglong , Yin Yaoyao , Wei Danzhu , Xu Tian , Wang Chaonan , Xu Meifeng , Peng Cong 
Published: April 2021

Abstract
Because of the demand for low-cost optical trapping small particles without directly touching in subwavelength volume, a liquid-core metal-cladding waveguide (LCMW) structure was put forward, and it retained all the merits of MCW, such as free space coupling, a large detection area, and polarization independence. LCMW was used for optical trapping of SiO2 colloid particles. The reflectivity of the guiding layer was monitored to investigate the factors influencing the self-assembly speed of the SiO2 particles (time for the reflectivity to reach a stable state). The results demonstrate that a smaller ultimate reflectivity of light, longer light-off time, or a higher sample refractive index increases the required optical trapping time for the SiO2 colloid particles to reach a stable state.
Electronic and optical properties of ASc2S4 (A = Ca, Sr) compounds
Authors: Gencer Aysenur 
Published: April 2021

Abstract
This study investigates the ASc2S4 (A = Ca, Sr) compounds having an AB2O4-type structure of orthorhombic crystal nature. The calculated formation enthalpies reveal the thermodynamic stability of these compounds. In addition, the mechanical and dynamical stabilities are found as well. The detailed electronic properties are studied using Perdew-Burke-Ernzerhof functional within the Generalized Gradient Approximation (GGA-PBE) and DFT + U methods. The ASc2S4 compounds are found to be semiconductor due the electronic band structures. The band gaps are determined as 1.11 eV and 1.25 eV using the GGA-PBE method, and 1.54 eV and 1.64 eV using the DFT + U method for CaSc2S4 and SrSc2S4, respectively. The orbital contributions to the partial density of states are investigated in detail. Furthermore, the optical properties of these compounds are obtained using the Bethe-Salpeter Equation (BSE) to consider the electron-hole interactions. The optical properties of the ASc2S4 compounds such as refractive indexes, extinction coefficients, absorption coefficients and loss functions are determined. This study fills the gap in the literature concerning the compounds that have S atoms instead of O atoms in AB2O4, while also revealing the electronic and optical properties of ASc2S4 (A = Ca, Sr) compounds in detail.
Diverse novel computational wave solutions of the time fractional Kolmogorov—Petrovskii - Piskunov and the (2 + 1)-dimensional Zoomeron equations
Authors: M A Khater Mostafa , El-Sayed Ahmed A , Alfalqi S H , Alzaidi J F 
Published: April 2021

Abstract
The numerical wave solutions of two fractional biomathematical and statistical physics models (the Kolmogorov—Petrovskii - Piskunov (KPP) equation and the (2 + 1)-dimensional Zoomeron (Z) equation) are investigated in this manuscript. Many novel analytical solutions in different mathematical formulations such as trigonometric, hyperbolic, exponential, and so on can be constructed using the generalized Riccati—expansion analytical scheme and the Caputo—Fabrizio fractional derivative. The fractional nonlinear evolution equation is converted into an ordinary differential equation with an integer order using this fractional operator. The obtained solution is used to describe the transmission of a preferred allele and the nonlinear interaction of moving waves, and the relative wave mode’s amplitude dynamic. To illustrate the fractional examined models, several drawings are explained in two dimensions and density plots.
The art of simulating the early universe.
Part I. Integration techniques and canonical cases
Authors: Figueroa Daniel G. , Florio Adrien , Torrenti Francisco , Valkenburg Wessel 
Published: April 2021

Abstract
We present a comprehensive discussion on lattice techniques for the simulation of scalar and gauge field dynamics in an expanding universe. After reviewing the continuum formulation of scalar and gauge field interactions in Minkowski and FLRW backgrounds, we introduce the basic tools for the discretization of field theories, including lattice gauge invariant techniques. Following, we discuss and classify numerical algorithms, ranging from methods of 𝒪(δ t2) accuracy like staggered leapfrog and Verlet integration, to Runge-Kutta methods up to 𝒪(δ t4) accuracy, and the Yoshida and Gauss-Legendre higher-order integrators, accurate up to 𝒪(δ t10). We adapt these methods for their use in classical lattice simulations of the non-linear dynamics of scalar and gauge fields in an expanding grid in 3+1 dimensions, including the case of
`self-consistent' expansion sourced by the volume average of the fields' energy and pressure densities. We present lattice formulations of canonical cases of: i) Interacting scalar fields, ii) Abelian (1) gauge theories, and iii) Non-Abelian (2) gauge theories. In all three cases we provide symplectic integrators, with accuracy ranging from 𝒪(δ t2) up to 𝒪(δ t10). For each algorithm we provide the form of relevant observables, such as energy density components, field spectra and the Hubble constraint. We note that all our algorithms for gauge theories always respect the Gauss constraint to machine precision, including when `self-consistent' expansion is considered. As a numerical example we analyze the post-inflationary dynamics of an oscillating inflaton charged under (2)×(1). We note that the present manuscript is meant to be part of the theoretical basis for the code 𝒞osmoℒattice, a multi-purpose MPI-based package for simulating the non-linear evolution of field theories in an expanding universe, publicly available at http://www.cosmolattice.net.
Supersymmetric ν-inflaton Dark Matter
Authors: Bastero-Gil Mar , Torres Manso António 
Published: April 2021

Abstract
We present the supersymmetric extension of the unified model for inflation and Dark Matter studied in ref. [1]. The scenario is based on the incomplete decay of the inflaton field into right-handed (s)neutrino pairs. By imposing a discrete interchange symmetry on the inflaton and the right-handed (s)neutrinos, one can ensure the stability of the inflaton field at the global minimum today, while still allowing it to partially decay and reheat the Universe after inflation. Compatibility of inflationary predictions, BBN bounds and obtaining the right DM abundance for the inflaton Dark Matter candidate typically requires large values of its coupling to the neutrino sector, and we use supersymmetry to protect the inflaton from potentially dangerous large radiative corrections which may spoil the required flatness of its potential. In addition, the inflaton will decay now predominantly into sneutrinos during reheating, which in turn give rise both to the thermal bath made of Standard Model particles, and inflaton particles. We have performed a thorough analysis of the reheating process following the evolution of all the partners involved, identifying the different regimes in the parameter space for the final Dark Matter candidate. This as usual can be a WIMP-like inflaton particle or an oscillating condensate, but we find a novel regime for a FIMP-like candidate.
Effect of Nd:YAG laser irradiation on microtensile bond strength of universal adhesives to dentin
Authors: Jafarnia Shiva , Zeinaddini Meymand Javad , Zandkarimi Fateme , Saberi Sogol , Valanezhad Alireza , Shahabi Sima 
Published: April 2021

Abstract
The aim of this study was to evaluate the effect of neodymium:yttrium–aluminum–garnet (Nd:YAG) laser irradiation before adhesive application on microtensile bond strength of resin composite to dentin surface. Materials and methods: in this experiment, 40 human extracted third molar teeth were chosen and the occlusal surface was cut to achieve a flat dentin surface. Groups were divided based on the adhesives (G-Premio Bond or Clearfil S3 Bond) and the presence or absence of Nd:YAG laser application. All the samples were restored with resin composite and subjected to a universal testing machine for a microtensile bond strength test. Fracture mode for each failure was analyzed under the stereomicroscope. According to the results, there was a significant difference between the two adhesives with Nd:YAG laser irradiation. The application of laser enhanced the microtensile bond strength in both adhesives. In all groups, regardless of laser application, adhesive failure was dominant between fracture patterns. It was concluded that Nd:YAG laser irradiation on dentin surface prior to adhesive application has a positive effect and significantly increases the microtensile bond strength of restoration to the tooth.
A metrological approach to quantities that are counted and the unit one
Authors: Brown Richard J C 
Published: April 2021

Abstract
There has long been debate over how to treat dimensionless quantities, or quantities with the unit one, within the International System of Units (SI). These arguments have been brought into sharper focus because of the increasing application of metrological principles in areas such as chemistry, biology and nanoscience where counting measurements are common. This has caused debates about how the SI should address counting quantities and the unit one (symbol 1). This article reviews the types of quantities with the unit one, how these quantities may be expressed together with their uncertainty and how this relates to counting. The qualities of counting quantities are explored in more detail and the range of possibilities for dealing with the unit one for counting are discussed. It is proposed that the SI should allow only the unit one for counting, but that downstream of the SI there may well be benefits from standardising the use of more descriptive, technical area specific ‘units’ for expressing the results of counting. As with all measurement it is essential that a full description, in words, of the counting quantity being expressed accompanies the measurement result.
Empirical decomposition and error propagation of medium-term instabilities in half-life determinations
Authors: Pommé S , Pelczar K 
Published: April 2021

Abstract
A least-squares fit of exponential functions to a measured radioactive decay rate curve provides an estimate of the half-life and its statistical uncertainty in the assumption that all deviations from the theoretical curve are purely of a random nature. The result may be biased and the error underestimated as soon as the experiment suffers instabilities that exceed the duration of individual measurements. Contrary to long-term systematic errors, medium-frequency cyclic perturbations may be observable as autocorrelated structures in the residuals. In this work, an empirical decomposition algorithm is used to separate medium-frequency effects from the random statistical component in the fit residuals, such that custom error propagation factors can be calculated. A theoretical study of error propagation is made for sine and square wave perturbations. The empirical decomposition method is demonstrated on a synthetic spectrum, a time series of solar neutrino detection rates, and two experimental decay curves of 134Cs measured in an ionisation chamber.
Auditory stimulus-response modeling with a match-mismatch task
Authors: de Cheveigné Alain , Slaney Malcolm , Fuglsang Søren A , Hjortkjaer Jens 
Published: April 2021

Abstract

Objective. An auditory stimulus can be related to the brain response that it evokes by a stimulus-response model fit to the data. This offers insight into perceptual processes within the brain and is also of potential use for devices such as brain computer interfaces (BCIs). The quality of the model can be quantified by measuring the fit with a regression problem, or by applying it to a classification task and measuring its performance. Approach. Here we focus on a match-mismatch (MM) task that entails deciding whether a segment of brain signal matches, via a model, the auditory stimulus that evoked it. Main results. Using these metrics, we describe a range of models of increasing complexity that we compare to methods in the literature, showing state-of-the-art performance. We document in detail one particular implementation, calibrated on a publicly-available database, that can serve as a robust reference to evaluate future developments. Significance. The MM task allows stimulus-response models to be evaluated in the limit of very high model accuracy, making it an attractive alternative to the more commonly used task of auditory attention detection. The MM task does not require class labels, so it is immune to mislabeling, and it is applicable to data recorded in listening scenarios with only one sound source, thus it is cheap to obtain large quantities of training and testing data. Performance metrics from this task, associated with regression accuracy, provide complementary insights into the relation between stimulus and response, as well as information about discriminatory power directly applicable to BCI applications.
Long term evolution of fast ripples during epileptogenesis
Authors: Harrach Mariam Al , Benquet Pascal , Wendling Fabrice 
Published: April 2021

Abstract

Objective. Fast ripples (FRs) have received considerable attention in the last decade since they represent an electrophysiological biomarker of the epileptogenic zone (EZ). However, the real dynamics underlying the occurrence, amplitude, and time-frequency content of FRs generation during epileptogenesis are still not well understood. This work aims at characterizing and explaining the evolution of these features. Approach. Intracortical electroencephalographic signals recorded in a kainate mouse model of temporal lobe epilepsy were processed in order to compute specific FR features. Then realistic physiologically based computational modeling was employed to explore the different elements that can explain the mechanisms of epileptogenesis and simulate the recorded FR in the early and late latent period. Main results. Results indicated that continuous changes of FR features are mainly portrayed by the epileptic (pathological) tissue size and synaptic properties. Furthermore, the microelectrodes characteristics were found to dramatically affect the observability and spectral/temporal content of FRs. Consequently, FRs evolution seems to mirror the continuous pathophysiological mechanism changes that occur during epileptogenesis as long as the microelectrode properties are taken into account. Significance. Our study suggests that FRs can account for the pathophysiological changes which might explain the EZ generation and evolution and can contribute in the treatment plan of pharmaco-resistant epilepsies.