bluuebunny/crossref_metadata_2025_split huggingface dataset:
Color-neutral, semitransparent organic photovoltaics for power window applications
Authors: Li Yongxi , Guo Xia , Peng Zhengxing , Qu Boning , Yan Hongping , Ade Harald , Zhang Maojie , Forrest Stephen R. 
Published: August 2020

Significance
We demonstrate a semitransparent organic photovoltaic cell that achieves a power conversion efficiency of 10.8% and visible transparency of ∼50% using a nonfullerene acceptor (NFA) featuring strong near-infrared (NIR) absorption and simple synthesis. Contrary to expectations, stronger NIR absorption and closer molecular packing are obtained by employing an additive in these partially, instead of fully fused, rigid NFAs. By combining NIR-absorbing material sets with an optical outcoupling structure as well as transparent electrode, we overcome the trade-offs between efficiency, transparency, and device appearance. These results surpass other semitransparent solar cell technologies based on organic and other thin-film materials systems, showing a promising future for ST-OPVs as power-generating windows and other solar energy harvesting applications.
Rapid formation of human immunodeficiency virus-like particles
Authors: Bednarska Joanna , Pelchen-Matthews Annegret , Novak Pavel , Burden Jemima J. , Summers Peter A. , Kuimova Marina K. , Korchev Yuri , Marsh Mark , Shevchuk Andrew 
Published: August 2020

Significance
Currently, our knowledge of individual virus particle assembly kinetics is based solely on studies of the dynamics of fluorescent puncta corresponding to the viral structural protein called Gag labeled with fluorescent proteins (e.g., green fluorescent protein [GFP]) observed by fluorescence microscopy in membranes of cells. However, GFP tagging affects virus particle assembly and release. We directly measured topological changes during HIV-like particle assembly and found that they can reach full size in 20 s and release in 0.5 to 3 min. Compared to previous estimates of ∼8-min assembly time and 30- to 60-min release time, this is more than 10 times faster. In our opinion this is a highly important discovery that challenges current views on virus replication mechanisms.
A specialized population of Periostin-expressing cardiac fibroblasts contributes to postnatal cardiomyocyte maturation and innervation
Authors: Hortells Luis , Valiente-Alandi Iñigo , Thomas Zachary M. , Agnew Emma J. , Schnell Dan J. , York Allen J. , Vagnozzi Ronald J. , Meyer Evan C. , Molkentin Jeffery D. , Yutzey Katherine E. 
Published: August 2020

Significance
During the postnatal period, the heart undergoes important changes, including cardiomyocyte cell-cycle arrest and loss of regenerative capacity. While other cell types have been better characterized, the information related to postnatal cardiac fibroblasts (CFs) is limited. Here, we report a specialized population of highly proliferative periostin-expressing (Postn+) fibroblasts in the early postnatal heart that become quiescent at P30. In comparison, P7 Tcf21+ fibroblasts have distinct gene expression from Postn+ CFs. Notably, Postn+ CFs express proliferation and neuronal-related genes, while Tcf21+ CFs preferentially express extracellular-matrix–related genes. Ablation of Postn+ cells leads to reduced cardiomyocyte growth, mitotic activity, and binucleation with increased sympathetic nerve area. Thus Postn+ cells represent a specialized developmental CF population critical for postnatal cardiac maturation.
How a B family DNA polymerase has been evolved to copy RNA
Authors: Choi Woo Suk , He Peng , Pothukuchy Arti , Gollihar Jimmy , Ellington Andrew D. , Yang Wei 
Published: August 2020

Significance
RTX is a reverse transcriptase evolved in vitro from the B family DNA polymerase KOD. Structural analyses of RTX in complex with either a DNA duplex or an RNA–DNA hybrid and comparison with the apo, binary, and ternary complex structures of the original KOD polymerase shed light on how to engineer and alter substrate specificity of enzymes. Among the 16 substitutions that result in the reverse transcriptase activity, only six occur at the substrate-binding surface, and the others change domain–domain interfaces in the polymerase to enable RNA–DNA hybrid binding and reverse transcription. The intrinsically flexible Thumb domain seems to play a major role in accommodating the RNA–DNA hybrid product distal to the active site.
Constraining crustal silica on ancient Earth
Authors: Keller C. Brenhin , Harrison T. Mark 
Published: August 2020

SignificanceOn geologic timescales, Earth’s habitable climate is maintained by a negative feedback process wherein atmosphericCO2is consumed by reaction with silicate rocks during erosion and weathering. However, relative to modern continental crust, many models propose an ancient crust that was thinner, denser, and significantly lower in silica for the first 1 to 2 billion years of Earth history. Like modern oceanic crust, such mafic crust would likely be poorly exposed to the atmosphere, resulting in a less climatically stable early Earth. We find that two geologic processes (mantle cooling and atmospheric oxidation) significantly compromise some previous methods for estimating ancient crustal composition. Accounting for these factors results in estimates much closer to the composition of modern continental crust.
The glutathione peroxidase 8 (GPX8)/IL-6/STAT3 axis is essential in maintaining an aggressive breast cancer phenotype
Authors: Khatib Anees , Solaimuthu Balakrishnan , Ben Yosef Michal , Abu Rmaileh Areej , Tanna Mayur , Oren Gidi , Schlesinger Frisch Michal , Axelrod Jonathan H. , Lichtenstein Michal , Shaul Yoav D. 
Published: August 2020

Significance
The cancer-dependent metabolic rewiring is mainly associated with the synthesis of building blocks that are needed to fulfill the proliferating cell metabolic requirements. However, the proliferation-independent instructive role of metabolic enzymes in tumor plasticity is still unclear. Here, we introduce glutathione peroxidase 8 (GPX8) as a metabolic enzyme that regulates cancer aggressiveness. We found that lack of GPX8 suppresses the aggressive phenotype and stemness features of the tumor cells. Mechanistically, these cells express a nonfunctional IL-6 receptor, which fails to interact with IL-6. This impaired binding hinders the activation of the downstream JAK/STAT3 signaling pathway, thereby inhibiting cancer cells transition to aggressive phenotypes. Thus, we present this GPX8/IL-6/STAT3 axis as a prototype of metabolic enzymes regulating cancer aggressiveness-associated signaling pathways.
Autoantibodies against central nervous system antigens in a subset of B cell–dominant multiple sclerosis patients
Authors: Kuerten Stefanie , Lanz Tobias V. , Lingampalli Nithya , Lahey Lauren J. , Kleinschnitz Christoph , Mäurer Mathias , Schroeter Michael , Braune Stefan , Ziemssen Tjalf , Ho Peggy P. , Robinson William H. , Steinman Lawrence 
Published: August 2020

Significance
Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS). B cells play a key role in MS immunopathology, as demonstrated by the success of B cell-directed therapies; however, the target antigen of MS remains unknown. Using a combination of ELISpot-based prescreening of peripheral blood mononuclear cells followed by investigation of antibody specificity with a CNS antigen array, we identified a population of MS patients characterized by a highly active B cell response. These individuals with MS, who have active B cell responses, exhibited heterogeneous interindividual anti-CNS antibody responses, although the antigenic specificity of the antibodies remained stable over time for each individual.
Probing primordial stochastic gravitational wave background with multi-band astrophysical foreground cleaning
Authors: Pan Zhen , Yang Huan 
Published: August 2020

Abstract
The primordial stochastic gravitational wave background (SGWB) carries first-hand messages of early-universe physics, possibly including effects from inflation, preheating, cosmic strings, electroweak symmetry breaking, and etc. However, the astrophysical foreground from compact binaries may mask the SGWB, introducing difficulties in detecting the signal and measuring it accurately. In this paper, we propose a foreground cleaning method taking advantage of gravitational wave observations in other frequency bands. We apply this method to probing the SGWB with space-borne gravitational wave detectors, such as the laser interferometer space antenna (LISA). We find that the spectral density of the LISA-band astrophysical foreground from compact binaries (black holes and neutron stars) can be predicted with percent-level accuracy assuming 10-years’ observations of third-generation GW detectors, e.g., cosmic explorer. While this multi-band method does not apply to binary white dwarfs (BWDs) which usually merger before entering the frequency band of ground-based detectors, we limit our foreground cleaning to frequency higher than ∼5 mHz, where all galactic BWDs can be individually resolved by LISA and the shape of the spectral density of the foreground from extragalactic BWDs can be reconstructed and/or modeled with certain uncertainties. After the foreground cleaning, LISA’s sensitivity to the primordial SGWB will be substantially improved for either two LISA constellations where SGWB can be measured by cross correlating their outputs or only one constellation with three spacecrafts where SGWB can be measured by contrasting the responses of a signal channel and a null channel.
Influence of the residual gas damping noise in the test of the gravitational inverse-square law
Authors: Ke Jun , Luo Jie , Tan Yu-Jie , Shao Cheng-Gang 
Published: August 2020

Abstract
Many theories, such as the unification theories that would include gravitation, predict deviations from Newtonian inverse-square law (ISL) at short range. Many high precision experiments have been performed, but additional experiments are still of high scientific importance. Here, we discuss the torque thermal noise caused by residual gas damping, especially the effect of squeeze-film damping, in a proposed ISL experiment at the range of tens of microns. In such experiments, torsion pendulums are usually used to probe the torque interactions between the detector and the attractor, of which the thermal noise should be considered carefully due to the high sensitivity. By introducing a thermal accommodation coefficient, we can accurately model the torque noise of the residual gas damping as a combination of elastic and inelastic collisions. The results show that the noise will increase significantly at short separations between the pendulum and the surrounding components. In particular, when the separation is smaller than 40 μm, the squeeze-film damping may be larger than the internal damping of the pendulum used in present experiments, and become the fundamental limit for the experiments in the shorter range.
A second order Calderón’s method with a correction term and a priori information
Authors: Shin Kwancheol , Mueller Jennifer L 
Published: August 2020

Abstract
Calderón’s method is a direct linearized reconstruction method for the inverse conductivity problem with the attribute that it can provide absolute images of both conductivity and permittivity with no need for forward modeling. In this work, an explicit relationship between Calderón’s method and the D-bar method is provided, facilitating a ‘higher-order’ Calderón’s method in which a correction term is included, derived from the relationship to the D-bar method. Furthermore, a method of including a spatial prior is provided. These advances are demonstrated on simulated data and on tank data collected with the ACE1 EIT system.
Positron scattering and transport in liquid helium
Authors: Cocks D G , McEachran R P , Boyle G J , Cheng E , White R D 
Published: August 2020

Abstract
In previous papers we have proposed a method for the ab initio calculation of fully differential cross-sections for electron scattering in liquids and applied it to liquid argon, xenon and krypton. In this paper, we extend the procedure to the consideration of positron scattering in liquid helium, which is complicated by the annihilation process as well as the fact that the electron definition for the region ‘owned’ by a target atom used previously does not have a positron analogue. We explore several physically motivated definitions to obtain effective positron scattering in the dense fluid. We find that our calculations of a pure helium system cannot precisely match experimental measurements, however by including a small admixture (<0.1%) of an impurity, we can obtain reasonable agreement in the dense gas phase. In contrast, the comparison between our calculations and liquid phase measurements is less satisfactory. This provides motivation to explore further multiple scattering effects in the theory.
The use of oscillator-strength sum rules for evaluating the angular-momentum dependence of the blackbody-radiation-induced broadening and shift of Rydberg-state energy levels
Authors: Glukhov I L , Kamenski A A , Ovsiannikov V D 
Published: August 2020

Abstract
First evaluations of the blackbody-radiation (BBR)-induced shift and broadening of highly excited Rydberg states were based on the account of only the first term of the expansion for the Planck’s distribution in powers of the ratio of the BBR-photon energy to the environmental thermal energy. The corresponding asymptotic expression for the shift is proportional to a sum rule for the oscillator strengths, which is identical for all states, independently of their principal and angular-momentum quantum numbers. The broadening appeared proportional to the sum of the oscillator-strength first moments, which is dependent on only the principal quantum number, being independent of the state’s angular momentum. In this article, we demonstrate that the account of higher-order terms of the Planck’s distribution expansion provides corrections revealing the dependence of asymptotic shift and broadening on the Rydberg-state principal and angular-momentum quantum numbers. The strongest corrections are observed for states with low angular momenta, in agreement with earlier performed numerical calculations. Sum rules for higher moments of oscillator strengths are used for evaluating the corrections for the BBR-induced broadening and shift of Rydberg-state energy levels in neutral atoms and ions of arbitrary nuclear charge Z.
Ion beam modification of the Ni-Si solid-phase reaction: The influence of substrate damage and nitrogen impurities introduced by ion implantation
Authors: van Stiphout K , Geenen F A , Santos N M , Miranda S M C , Joly V , Demeulemeester J , Mocuta C , Comrie C M , Detavernier C , Pereira L M C , Temst K , Vantomme A 
Published: August 2020

Abstract
We report on the growth of thin NiSi films via the thermal reaction of Ni layers (13–35 nm) with Si(100) substrates modified by ion implantation. By introducing substrate damage or nitrogen impurities prior to the solid-phase reaction, several properties of the NiSi films can be modified: the formation temperature, texture, diffusion-limited growth rate and morphological stability. As some of the modifications to the NiSi films are rooted in the early silicide phases preceding the NiSi phase, particularly its formation temperature, special attention is devoted to the growth of the amorphous Ni-Si alloy and the crystalline δ-Ni2Si and θ-Ni2Si phases.
We employed a number of experimental techniques, including in situ synchrotron x-ray diffraction (XRD), in situ Rutherford backscattering spectrometry (RBS), in situ sheet resistance measurements, ex situ ion beam channelling and ex situ pole figure measurements. We show that both the formation temperature of the NiSi films and the intensity of epitaxial and axiotaxial components of the NiSi texture can be either lowered or raised by selecting appropriate implantation conditions. Agglomeration of the NiSi films at high temperature (> 700 °C) can be slowed down, either by slowing down the mobility of the Ni and Si atoms, or by removing the morphologically destabilizing axiotaxial texture. Our results emphasize the strong interwoven nature of phase formation, texture and morphological degradation. We illustrate that the kinetics of the early stages of thin film reactions consist of more than just diffusion, i.e. nucleation can also play a crucial role.
Modelling of time development of cylindrical underwater spark channel in compressible viscous liquid
Authors: Kolacek Karel , Stelmashuk Vitaliy , Tuholukov Andrii , Hoffer Petr , Schmidt Jiri , Straus Jaroslav , Frolov Alexandr , Oliva Eduardo 
Published: August 2020

AbstractIn this study, a new finite-difference cylindrical model of long underwater spark is developed that allows us to numerically calculate the time evolution of the underwater spark channel from a given power input. A one dimensional simulation starts in the breakdown moment. The whole time development is divided into time steps of equal duration. The investigated region consists of a homogeneous cylindrical central column filled with weakly ionized vapour and its atomic fragments, and co-axial cylindrical liquid slabs of equal thickness in the beginning. In each time step, some energy (experimentally given and reduced by losses spent on dissociation, excitation, and ionization) is delivered into the central plasma column. This energy is partly irradiated, out-conducted, spent on mechanical work, and/or used for an increase of inner energy of the plasma column. This ambiguity enables us in future to fit, e.g. the plasma column diameter at the end of energy input to its experimental value. The model shows that plasma channel expansion generates a primary pressure wave propagating with supersonic velocity, and a subsequent secondary pressure wave that propagates with sound velocity. An advantage of this approach is that the present solution with constant coefficients can be relatively easily upgraded to a solution with variable coefficients.
Interface charge accumulation dynamics in 3D and quasi-2D perovskite solar cells
Authors: Liu Guilin , Zhou Ning , Tan Shunquan , Zhang Juchen , Chen Qi , Zhou Huanping 
Published: August 2020

Abstract
Perovskite solar cells (PSCs) have rapidly developed in recent years with the advantages of high efficiency and low cost. Although PSCs are the fastest-advancing solar technology to date, bottlenecks such as J–V hysteresis have limited the further development significantly. In this work, we have investigated the in-depth mechanism of hysteresis in both three-dimensional (3D) and quasi-2D (Q-2D) planar p-i-n PSCs. We conducted scanning-rate-dependent and temperature-dependent measurements to distinguish the ion migration and the capacitive charging. The coefficient for capacitance and pseudocapacitance from the J–V curves are further employed to analysis the hysteresis. It is found that both capacitance and ion migration contribute to the J–V hysteresis, but play different roles in 3D and Q-2D perovskite devices. In 3D PSCs, the ion migration has substantial impacts on the J–V hysteresis, wherein ions are tending to move. While in the Q-2D PSCs, the capacitance extends the characteristic charging time, which is mainly responsible for J–V hysteresis. These findings will help to effectively suppress the hysteresis for 3D and Q-2D PSCs, eventually benefiting device performance and long term stability.
Graphite films/carbon fiber fabric/ polyurethane composites with ultrahigh in-plane thermal conductivity and enhanced mechanical properties
Authors: Ren Liucheng , Ren Yanjuan , Zhang Yafei , Orzechowski Kazimierz , Kułacz Karol , Pocheć Michał , Bai Shu-Lin 
Published: August 2020

Abstract
Thermally conductive composites have attracted great attention in virtue of their crucial role in thermal management. In this work, laminated composites were prepared by laying graphite films (GF) and carbon fiber fabrics (CF) in a certain order, then penetrating thermoplastic polyurethane (TPU), finally hot-pressing. In order to enhance the inter-layer strength, the graphite films were perforated with arrays of 1 mm holes in diameter which have intervals of 4 mm and permit the seeping of liquid TPU through them. The in-plane thermal conductivity (TC) of composite reaches 242 W m−1 K−1 with the loading of 25 vol% GF and 60 vol% CF, which is 1210 times that of pure TPU. The great improvement of TC is ascribed to the thermal conductive pathways formed by continuous GF with ultrahigh TC. The addition of CF enhances markedly the mechanical properties of composites. Bending strength and modulus of composites are 5.56 and 17.09 times that of pure TPU, respectively. The proposed design and manufacture method are facile and effective to obtain polymeric composites simultaneously with high TC and good mechanical properties.
Shape control of piezoelectric bimorph by piezo response function and global optimization algorithms: a comparative study
Authors: Sumit  , Shukla Rahul , Sinha A K 
Published: August 2020

Abstract
In this paper shape control optimization of piezoelectric bimorph is done by piezo response function (PRF) and global optimization technique. PRF is used to formulate the optimization problem and global optimization algorithm is used to minimize the error between the target and the achieved shape. The performance of four global optimization techniques, simulated annealing (SA), genetic algorithm, particle swarm optimization and teacher learning based optimization are compared for the shape control of piezoelectric bimorph. 28 piezoelectric actuators are used in the piezoelectric bimorph to generate the sinusoidal profile, elliptical profile and arbitrary deformation profile by the external load. PRF is calculated by solving finite element model of piezoelectric bimorph and, optimization of electric potential with safety limit is done to achieve the target profiles by using all the aforementioned optimization techniques. SA gives best value of the objective function. At optimum electrode potential, the target and, achieved sinusoidal, elliptical and arbitrary deformation profiles obtained by SA at 5 × 107 computation, matches closely with root mean square (RMS) errors of 0.72, 12.18 and 28.86 nm, respectively. Subsequently, a robust and fully reproducible method for the shape control of piezo actuated deformable mirrors and smart structures is developed.