bluuebunny/crossref_metadata_2025_split huggingface dataset:
Matter-antimatter asymmetry induced by non-linear electrodynamics
Authors: Benaoum H B , Övgün A 
Published: April 2021

Abstract
In this work, we propose an economical model to address some open cosmological problems such as the absence of the initial cosmological singularity, an early acceleration of the Universe and the generation of matter–antimatter asymmetry. The model is based on a scenario in which the early Universe consists of a non-linear electrodynamics (NLED) fields. It is found that the NLED model has an equation of state

p
=

1

3

ρ
−

4

3

β

ρ

1
+
α

which shows that the Universe undergoes an early epoch acceleration to a radiation era given by

p
=

1

3

ρ

. We show that the singularities in the energy density, pressure and curvature are absent at early stages. In our scenario, the baryon asymmetry is generated by the non-linearity parameter β. Additionally, we calculate the resulting baryon asymmetry and discuss how a successful gravitational baryogenesis is obtained for different values of the model’s parameter space.
Kalb–Ramond scalar QED multiple vacua
Authors: Smailagic Anais , Spallucci Euro 
Published: April 2021

Abstract
We study a model of interacting vector and Kalb–Ramond gauge fields in a non-trivial Higgs vacuum generated by a charged and a neutral scalar field. The system admits different vacua for different v.e.v. of the two Higgs fields. Our primary interest in this paper regards the ‘mixed phase’ where both the photon and the Kalb–Ramond acquire a mass. In this phase we compute the interaction potential energy between static test charges. It turns out that the limit in which the photon becomes massless, while the Kalb–Ramond remains massive, leads to a Cornell confining potential between test charges.
Revisiting the thermal conductivity of Si, Ge and diamond from first principles: roles of atomic mass and interatomic potential
Authors: Guo Guiming , Yang Xiaolong , Carrete Jesús , Li Wu 
Published: April 2021

Abstract
The thermal conductivity (κ) of nonmetals is determined by the constituent atoms, the crystal structure and interatomic potentials. Although the group-IV elemental solids Si, Ge and diamond have been studied extensively, a detailed understanding of the connection between the fundamental features of their energy landscapes and their thermal transport properties is still lacking. Here, starting from first principles, we analyze those factors, including the atomic mass (m) and the second- (harmonic) and third-order (anharmonic) interatomic force constants (IFCs). Both the second- and third-order IFCs of Si and Ge are very similar, and thus Si and Ge represent ideal systems to understand how the atomic mass alone affects κ. Although the group velocity (v) decreases with increasing atomic mass (

v

−
1

∝

m

), the phonon lifetime (τ) follows the opposite trend (

τ
∝

m

). Since the contribution to κ from each phonon mode is approximately proportional v
2
τ, κ is lower for the heavier element, namely Ge. Although the extremely high thermal conductivity of diamond is often attributed to weak anharmonic scattering, the anharmonic component of the interatomic potential is not much weaker than those of Si and Ge, which seems to be overlooked in the literature. In fact, the absolute magnitude of the third-order IFCs is much larger in diamond, and the ratios of the third-order IFCs with respect to the second-order ones are comparable to those of Si and Ge. We also explain the experimentally measured κ of high-quality diamonds (Inyushikin et al 2018 Phys. Rev. B
97 144305) by introducing boundary scattering into the picture, and obtain good agreement between calculations and measurements.
Measurement of salinity in slurry based on modified electrical conductivity method
Authors: Yuan Jing , Zhang Minxi , Yu Guoliang 
Published: April 2021

Abstract
Salinity is an important factor in the management of inland and oceanic water resources. Currently, the electrical conductivity (EC) method is widely used for the measurement of salinity in different components of the environment. However, this method is not reliable for the measurement of salinity in slurry, as the conversion formula from the EC value to salinity does not consider fine particle size and its content. In this study, the salinity of slurry based on EC measurements was extensively investigated. In total, 1148 laboratory tests and 40 field tests were performed. The results indicate that the EC value is mainly influenced by the salinity, temperature, fine particle size, fine particle content, and sediment concentration of slurry. The fine particle size and its content play an important role in the measurement of salinity in slurry. The surface coefficient of the fine particles was herein considered as the parameter to indicate the effects of fine particle size and its content on the EC value. The results show that the effects of salinity and temperature on the EC measurement are more significant than that of the surface coefficient of fine particles and sediment concentration. Although the EC of slurry is positively and linearly related to salinity and temperature, it has negative relationships with the surface coefficient of fine particles and sediment concentration. Based on dimensional analysis and experimental data, a new formula was proposed for the calculation of salinity which considers the EC, sediment concentration, surface coefficient of fine particles, and temperature of the slurry. This modified conversion formula for the EC method was successfully tested with laboratory, field and other scholars’ data, which assures a reliable salinity measurement of slurry in shallow oligohaline water areas.
Low loss dielectric measurements in the frequency range 1–70 MHz by using a vector network analyser
Authors: Gregory A P , Hill G J , Barnett M A 
Published: April 2021

AbstractThe resonance of a coil inductor and a parallel-electrode capacitor can be used to determine the permittivity and loss angle of sheets of material at RF frequencies. By using high-stability instrumentation to measure resonant frequency and Q-factor, the loss angle of very low-loss materials can be determined with a resolution of below 10 microradians. In the 1970s much work went into developing Q-meter-based systems, based on series resonance, which were typically used for measuring the loss angle of polymers such as polyethylene. These systems were also used for measuring ceramics used as RF windows in prototype fusion reactors. This paper describes how one of these systems was updated to replace the now obsolete Q-meter with a vector network analyser (VNA), using parallel resonance. A second aspect to the work is calculation of the fringing (edge) capacitance between the electrodes, which are unguarded, by using MIT FastCap software. This enables measurements obtained by the equivalent-thickness method to be corrected for the effects of fringing capacitance. Measurements using an unmodified Q-meter system, a VNA-based system, and two other techniques are compared for polyethylene, fused silica, macor and alumina specimens. Good agreement is obtained. The measurements are presented with comprehensive evaluations of uncertainty.
Structure and transportation of electron vortices in near-critical density plasmas driven by ultrashort intense laser pulses
Authors: Yue D N , Chen M , Geng P F , Yuan X H , Sheng Z M , Zhang J , Dong Q L , Das A , Kumar G R 
Published: April 2021

Abstract
Structure and transportation of electron vortices in near-critical density plasmas driven by ultrashort intense laser pulses have been studied by multi-dimensional particle-in-cell simulations. Dimensional features of electron vortices are revealed. In two-dimensional geometry, two electron vortices and a quasi-static magnetic dipole are closely coupled. In three-dimensional geometry, a moving electron vortex ring associated with a closed magnetic ring moves in near-critical density plasmas. Such structure can transport some energy to the region where the laser pulse cannot reach. It is found that the motion of plasma ions makes the vortex magnetic energy dissipate quickly. These studies provide possible connection of electron vortices in nature with laser plasma experiments.
Improving the applicability of the Pauli kinetic energy density based semilocal functional for solids
Authors: Jana Subrata , Behera Sushant Kumar , Śmiga Szymon , Constantin Lucian A , Samal Prasanjit 
Published: April 2021

Abstract
The Pauli kinetic energy enhancement factor α = (τ − τ

W
)/τ
unif is an important density ingredient, used to construct many meta-generalized gradient approximations (meta-GGA) exchange–correlation (XC) energy functionals, including the very successful strongly constrained and appropriately normed (SCAN) semilocal functional. Another meta-GGA functional, known as MGGAC (2019 Phys. Rev. B
100 155140), is also proposed in recent time depending only on the α ingredient and based on the generalization of the Becke–Roussel approach with the cuspless hydrogen exchange hole density. The MGGAC functional is proved to be a very useful and competitive meta-GGA semilocal functional for electronic structure properties of solids and molecules. Based on the successful implication of the ingredient α, which is also useful to construct the one-electron self-interaction free correlation energy functional, here we propose revised correlation energy for MGGAC exchange functional which is more accurate and robust, especially for the high and low-density limits of the uniform density scaling. The present XC functional, named as revised MGGAC (rMGGAC), shows an impressive improvement for the structural and energetic properties of solids compared to its previous version. Moreover, the assessment of the present constructed functional shows to be quite useful in solid-state physics in terms of addressing several current challenging solid-state problems.
The rate by which mortality increase with age is the same for those who experienced chronic disease as for the general population
Authors: Ebeling Marcus , Rau Roland , Malmström Håkan , Ahlbom Anders , Modig Karin 
Published: April 2021

Abstract

Background
Mortality doubles approximately every 6–7 years during adulthood. This exponential increase in death risk with chronological age is the population-level manifestation of ageing, and often referred to as the rate-of-ageing.

Objective
We explore whether the onset of severe chronic disease alters the rate-of-ageing.

Methods
Using Swedish register data covering the entire population of the birth cohorts 1927–30, we analyse whether being diagnosed with myocardial infarction, diabetes or cancer results in a deviation of the rate-of-ageing from those of the total population. We also quantify the long-term mortality effects of these diseases, using ages with equivalent mortality levels for those with disease and the total population.

Results
None of the diseases revealed a sustained effect on the rate-of-ageing. After an initial switch upwards in the level of mortality, the rate-of-ageing returned to the same pace as for the total population. The time it takes for the rate to return depends on the disease. The long-term effects of diabetes and myocardial infarction amount to mortality levels that are equivalent to those aged 5–7 years older in the total population. For cancer, the level of mortality returns to that of the total population.

Conclusion
Our results suggest an underlying process of ageing that causes mortality to increase at a set pace, with every year older we become. This process is not affected by disease history. The persistence of the rate-of-ageing motivates a critical discussion of what role disease prevention can play in altering the progression of ageing.
Heidegger, classical reception and the discourse of modernity: a crisis in thinking
Authors: Walsh Joseph M 
Published: April 2021

Abstract
Heidegger, perhaps the most influential philosopher of the last century, sought to do something with the Greeks never done before: to establish a new tradition of thinking. He saw in their literature and philosophy a concern with what is most essential and vital to man, and which has been glossed over and forgotten in modern thought. Controversial as his readings are, the exploration given here of Heidegger’s attempt to revive the spirit of Greek thinking reveals not only the fundamentally receptive nature of his philosophy but also the philosophical import of classical reception. While few would argue that Heidegger initiated a new tradition, he set in motion an intellectual crisis surrounding how the ills of modernity are rooted in modes of thought we must overcome. By making the Greeks the solution to this, Heidegger shifted the so-called ‘discourse of modernity’ to an assessment of the Greek’s impact on thinking today and their potential for us to think anew. As such, he made classical reception the vehicle for both understanding and critiquing the form of Modernity and its thinking. Therein lies the value of Heidegger for classical reception, because he gives it the intellectual impetus to confront what man is today.
Spending Political Capital
Authors: Campbell Arthur 
Published: April 2021

Abstract
An important task for organisations is establishing truthful communication between parties with differing interests. This task is made particularly challenging when the accuracy of the information is poorly observed or not at all. In these settings, incentive contracts based on the accuracy of information will not be very effective. This paper considers an alternative mechanism that does not require any signal of the accuracy of any information communicated to provide incentives for truthful communication. Rather, an expert sacrifices future participation in decision-making to influence the current period’s decision in favour of their preferred project. This mechanism captures a notion often described as ‘political capital’ whereby an individual is able to achieve their own preferred decision in the current period at the expense of being able to exert influence in future decisions (‘spending political capital’). When the first-best is not possible in this setting, I show that experts hold more influence than under the first-best and that, in a multi-agent extension, a finite team size is optimal. Together these results suggest that a small number of individuals hold excessive influence in organisations.
What can heart failure trialists learn from oncology trialists?
Authors: Zannad Faiez , Cotter Gad , Alonso Garcia Angeles , George Suzanne , Davison Beth , Figtree Gemma , Prasad Krishna , Rockhold Frank , Schilsky Richard L , Stockbridge Norman , Pitt Bertram , Butler Javed 
Published: April 2021

AbstractGlobally, there has been little change in mortality rates from cardiovascular (CV) diseases or cancers over the past two decades (1997–2018). This is especially true for heart failure (HF) where 5-year mortality rates remain as high as 45–55%. In the same timeframe, the proportion of drug revenue, and regulatory drug approvals for cancer drugs, far out paces those for CV drugs. In 2018, while cancer drugs made 27% of Food and Drug Administration drug approvals, only 1% of drug approvals was for a CV drug, and over this entire 20 year span, only four drugs were approved for HF in the USA. Cardiovascular trialists need to reassess the design, execution, and purpose of CV clinical trials. In the area of oncology research, trials are much smaller, follow-up is shorter, and targeted therapies are common. Cardiovascular diseases and cancer are the two most common causes of death globally, and although they differ substantially, this review evaluates whether some elements of oncology research may be applicable in the CV arena. As one of the most underserved CV diseases, the review focuses on aspects of cancer research that may be applicable to HF research with the aim of streamlining the clinical trial process and decreasing the time and cost required to bring safe, effective, treatments to patients who need them. The paper is based on discussions among clinical trialists, industry representatives, regulatory authorities, and patients, which took place at the Cardiovascular Clinical Trialists Workshop in Washington, DC, on 8 December 2019 (https://www.globalcvctforum.com/2019 (14 September 2020)).
Swainsonine producing performance of Alternaria oxytropis was improved by heavy-ion mutagenesis technology
Authors: liang Yan , Li Shangwei , Song Xiangdong , Zhou Deshun , Zhi Dejuan , Hao Baocheng , Liu Yu , Liang Jianping , Wang Zhen 
Published: April 2021

ABSTRACT
Swainsonine, an indolizidine alkaloid, is a promising anti-tumorigenic compound. Biological production of swainsonine was prospective, but the low swainsonine yield of wild type Alternaria oxytropis limited its production on a large scale. In present work, a stable A. oxytropis mutant UO1 with swanisonine yield of 14.84% higher than the wild-type strain was successfully obtained after heavy-ion irradiation. The A. oxytropis mutant UO1 and original wild-type strain were futher evaluated for SW concentrations under different factors. Results showed that the optimum culture temperature was 25°C. The optimum initial medium pH was 6.5 and the optimum inoculum size was 2 mL per 200 mL. Addition of the biosynthetic precursor L-pipecolic acids and L-lysine appropriately could increase the SW synthesis. These findings provided a theoretical basis and scientific data for the industrial production of swainsonine.
Chromosome-Level Assembly of the Atlantic Silverside Genome Reveals Extreme Levels of Sequence Diversity and Structural Genetic Variation
Authors: Tigano Anna , Jacobs Arne , Wilder Aryn P , Nand Ankita , Zhan Ye , Dekker Job , Therkildsen Nina Overgaard 
Published: April 2021

Abstract
The levels and distribution of standing genetic variation in a genome can provide a wealth of insights about the adaptive potential, demographic history, and genome structure of a population or species. As structural variants are increasingly associated with traits important for adaptation and speciation, investigating both sequence and structural variation is essential for wholly tapping this potential. Using a combination of shotgun sequencing, 10x Genomics linked reads and proximity-ligation data (Chicago and Hi-C), we produced and annotated a chromosome-level genome assembly for the Atlantic silverside (Menidia menidia)—an established ecological model for studying the phenotypic effects of natural and artificial selection—and examined patterns of genomic variation across two individuals sampled from different populations with divergent local adaptations. Levels of diversity varied substantially across each chromosome, consistently being highly elevated near the ends (presumably near telomeric regions) and dipping to near zero around putative centromeres. Overall, our estimate of the genome-wide average heterozygosity in the Atlantic silverside is among the highest reported for a fish, or any vertebrate (1.32–1.76% depending on inference method and sample). Furthermore, we also found extreme levels of structural variation, affecting ∼23% of the total genome sequence, including multiple large inversions (&gt; 1 Mb and up to 12.6 Mb) associated with previously identified haploblocks showing strong differentiation between locally adapted populations. These extreme levels of standing genetic variation are likely associated with large effective population sizes and may help explain the remarkable adaptive divergence among populations of the Atlantic silverside.
Homogenization of seismic point and extended sources
Authors: Capdeville Yann 
Published: April 2021

SUMMARYSeismic sources are mostly modelled as point sources: moment tensors associated with the gradient of a Dirac distribution. Such sources contain an infinite range of scales and induce a discontinuity in the displacement wavefield. This makes the near-source wavefield expensive to model and the event location complex to invert, in particular for large events for which many point sources are required. In this work, we propose to apply the non-periodic two-scale homogenization method to the wave equation source term for both force and couple-sources. We show it is possible to replace the Dirac point source with a smooth source term, valid in a given seismic signal frequency band. The discontinuous wavefield near-source wavefield can be recovered using a corrector that needs to be added to the solution obtained solving the wave equation with the smooth source term. We show that, compared to classical applications of the two-scale homogenization method to heterogeneous media, the source term homogenization has some interesting particularities: for couple-sources, the leading term of the homogenization asymptotic expansion is dependent on the fine spatial scale, depending on the source type, only one or two first terms of the expansion are non-zero and there is no periodic case equivalent (the source term cannot be made spatially periodic). For heterogeneous media, two options are developed. In the first one, only the source is homogenized while the medium itself remains the same, including its discontinuities. In the second one, both the source and the medium are homogenized successively: first the medium and then the source. We present a set of tests in 1-D and 2-D, showing accurate results both in the far-source and near-source wavefields, before discussing the interest of this work in the forward and inverse problem contexts.
Seismic reflectivity and transmissivity parametrization with the effect of normal in situ stress
Authors: Chen Fubin , Zong Zhaoyun , Jiang Man 
Published: April 2021

SUMMARY
In situ stress has a significant effect on the properties of underground formations, including seismic wave velocity, porosity and permeability, and further affects seismic reflectivity and transmissivity. Research works on the effect of in situ stress are helpful to construct more precise seismic reflection and transmission coefficient equations. However, previous studies on seismic reflectivity equations did not take the effect of normal in situ stress into consideration. The mechanism of stress on seismic reflectivity and transmissivity is still ambiguous. In this study, we propose new explicit equations to help analyse the changes of seismic reflectivity and transmissivity under the effect of normal in situ stress. First, we deduce the Christoffel equation on the basis of solid acoustoelastic theory. Then, we utilize appropriate boundary conditions to formulate analytical equations of the reflectivity at the interface between two stressed formations, which can provide some new insights into the role of in situ stress. The shear wave birefringence will vanish because we assume that the wave propagates in the X–Z plane. Different rock models with different lithology and saturation are used to analyse the variation of seismic reflectivity and transmissivity with normal stress and incident angle at the interface. The main effect of normal stress on reflection and transmission coefficients is to change amplitude and critical incident angle. When the upper and lower layers are sandstones, the critical incident angle decreases with the increase of normal in situ stress, which is consistent with previous studies. In addition, the reflectivity equation can be degenerated to the Zoeppritz equation when the normal in situ stress vanishes, which further validates that the equation proposed is correct. Seismic reflectivity equations that couple the effect of stress can lay a foundation for direct prediction of in situ stress.