bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elemental composition control of gold-titania nanocomposites by site-specific mineralization using artificial peptides and DNA
Authors: Ozaki Makoto , Imai Takahito , Tsuruoka Takaaki , Sakashita Shungo , Tomizaki Kin-ya , Usui Kenji 
Published: January 2021

AbstractBiomineralization, the precipitation of various inorganic compounds in biological systems, can be regulated in terms of the size, morphology, and crystal structure of these compounds by biomolecules such as proteins and peptides. However, it is difficult to construct complex inorganic nanostructures because they precipitate randomly in solution. Here, we report that the elemental composition of inorganic nanocomposites can be controlled by site-specific mineralization by changing the number of two inorganic-precipitating peptides bound to DNA. With a focus on gold and titania, we constructed a gold-titania photocatalyst that responds to visible light excitation. Both microscale and macroscale observations revealed that the elemental composition of this gold-titania nanocomposite can be controlled in several ten nm by changing the DNA length and the number of peptide binding sites on the DNA. Furthermore, photocatalytic activity and cell death induction effect under visible light (>450 nm) irradiation of the manufactured gold-titania nanocomposite was higher than that of commercial gold-titania and titania. Thus, we have succeeded in forming titania precipitates on a DNA terminus and gold precipitates site-specifically on double-stranded DNA as intended. Such nanometer-scale control of biomineralization represent a powerful and efficient tool for use in nanotechnology, electronics, ecology, medical science, and biotechnology.
Strange metal behaviour from charge density fluctuations in cuprates
Authors: Seibold Götz , Arpaia Riccardo , Peng Ying Ying , Fumagalli Roberto , Braicovich Lucio , Di Castro Carlo , Grilli Marco , Ghiringhelli Giacomo Claudio , Caprara Sergio 
Published: January 2021

AbstractBesides the mechanism responsible for high critical temperature superconductivity, the grand unresolved issue of the cuprates is the occurrence of a strange metallic state above the so-called pseudogap temperature T*. Even though such state has been successfully described within a phenomenological scheme, the so-called Marginal Fermi-Liquid theory, a microscopic explanation is still missing. However, recent resonant X-ray scattering experiments identified a new class of charge density fluctuations characterized by low characteristic energies and short correlation lengths, which are related to the well-known charge density waves. These fluctuations are present over a wide region of the temperature-vs-doping phase diagram and extend well above T*. Here we investigate the consequences of charge density fluctuations on the electron and transport properties and find that they can explain the strange metal phenomenology. Therefore, charge density fluctuations are likely the long-sought microscopic mechanism underlying the peculiarities of the metallic state of cuprates.
Varying pre-plasma properties to boost terahertz wave generation in liquids
Authors: Ponomareva Evgenia A. , Ismagilov Azat O. , Putilin Sergey E. , Tsypkin Anton N. , Kozlov Sergei A. , Zhang Xi-Cheng 
Published: January 2021

AbstractLaser-driven nonlinear phenomena can both reveal the structural features of materials and become the basis for the development of various translated technologies, including highly intense terahertz sources. Here we realize a modified single-color double-pulse excitation scheme for enhancing the terahertz wave generation in flat liquid jets, and we show that the pre-ionization effect is crucial for finding the optimal input conditions. The experimental results, being supported by numerical simulations, reveal the preference for longer pre-pulses to induce the effective ionization process and shorter signals for the strong laser-plasma interaction. In addition to the identified features of the terahertz wave energy enhancement with respect to the duration change for both pulses and their ratio variation, we state the possibility of achieving the optical-to-THz conversion efficiency value up to 0.1% in the case of double-pulse excitation of an α-pinene jet.
Interaction of edge exciton polaritons with engineered defects in the hyperbolic material Bi2Se3
Authors: Lingstädt Robin , Talebi Nahid , Hentschel Mario , Mashhadi Soudabeh , Gompf Bruno , Burghard Marko , Giessen Harald , van Aken Peter A. 
Published: January 2021

AbstractHyperbolic materials exhibit unique properties that enable intriguing applications in nanophotonics. The topological insulator Bi2Se3 represents a natural hyperbolic optical medium, both in the THz and visible range. Here, using cathodoluminescence spectroscopy and electron energy-loss spectroscopy, we demonstrate that Bi2Se3 supports room-temperature exciton polaritons and explore the behavior of hyperbolic edge exciton polaritons, which are hybrid modes resulting from the coupling of the polaritons bound to the upper and lower edges of Bi2Se3 nanoplatelets. We compare Fabry-Pérot-like resonances emerging in edge polariton propagation along pristine and artificially structured edges and experimentally demonstrate the possibility to steer edge polaritons by means of grooves and nanocavities. The observed scattering of edge polaritons by defect structures is found to be in good agreement with finite-difference time-domain simulations. Our findings reveal the extraordinary capability of hyperbolic polariton propagation to cope with the presence of defects, providing an excellent basis for applications such as nanooptical circuitry, nanoscale cloaking and nanoscopic quantum technology.
Pressure-induced Anderson-Mott transition in elemental tellurium
Authors: Oliveira Jaime F. , Fontes Magda B. , Moutinho Marcus , Rowley Stephen E. , Baggio-Saitovitch Elisa , Silva Neto Marcello B. , Enderlein Carsten 
Published: January 2021

AbstractElemental tellurium is a small band-gap semiconductor, which is always p-doped due to the natural occurrence of vacancies. Its chiral non-centrosymmetric structure, characterized by helical chains arranged in a triangular lattice, and the presence of a spin-polarized Fermi surface, render tellurium a promising candidate for future applications. Here, we use a theoretical framework, appropriate for describing the corrections to conductivity from quantum interference effects, to show that a high-quality tellurium single crystal undergoes a quantum phase transition at low temperatures from an Anderson insulator to a correlated disordered metal at around 17 kbar. Such insulator-to-metal transition manifests itself in all measured physical quantities and their critical exponents are consistent with a scenario in which a pressure-induced Lifshitz transition shifts the Fermi level below the mobility edge, paving the way for a genuine Anderson-Mott transition. We conclude that previously puzzling quantum oscillation and transport measurements might be explained by a possible Anderson-Mott ground state and the observed phase transition.
Inherited geochemical diversity of 3.4 Ga organic films from the Buck Reef Chert, South Africa
Authors: Alleon Julien , Bernard Sylvain , Olivier Nicolas , Thomazo Christophe , Marin-Carbonne Johanna 
Published: January 2021

AbstractArchean rocks contain crucial information about the earliest life forms on Earth, but documenting these early stages of biological evolution remains challenging. The main issue lies in the geochemical transformations experienced by Archean organic matter through its multi-billion-year geological history. Here we present spatially resolved chemical investigations conducted on 3.4 Ga organic films from the Buck Reef Chert, South Africa which indicate that they possess significantly different chemical compositions. Since these organic films all underwent the same post-depositional geological history, this geochemical diversity is most likely inherited, reflecting original chemical differences which were not completely obliterated by subsequent burial-induced degradation processes. These results demonstrate that early Archean organic films carry chemical information directly related to their original molecular compositions. This paves the way for the reconstruction of the initial chemical nature of organic microfossils found in ancient rocks, provided that the geologically-induced chemical transformations they underwent are properly constrained.
Dopant-site lattice turbulence of Cu-substituted Nb2O5 for efficient nitrogen electroreduction
Authors: Wang Jia , Li Guangkai , Wei Tao , Zhou Shizheng , Ji Xuqiang , Liu Xien 
Published: January 2021

Cu-Nb2O5 with abundant lattice disturbances anchored on a carbon material exhibits excellent activity and high selectivity for N2 electroreduction to NH3 in acidic electrolyte.
A non‐singular fast terminal sliding mode control scheme for residual current compensation inverters in compensated distribution networks to mitigate powerline bushfires
Authors: Roy Tushar Kanti , Mahmud Md Apel , Nasiruzzaman A. B. M. , Barik Md Abdul , Oo Amanullah Maung Than 
Published: January 2021

AbstractThis paper presents an approach to design a non‐singular fast terminal sliding model controller for residual current compensation inverters in compensated distribution networks to compensate the fault current due to most commonly occurred single line‐to‐ground faults. The main control objective is to completely eliminate the fault current in order to mitigate the impacts of powerline bushfires. A non‐singular fast terminal sliding surface is used to design the controller so that the residual current compensation inverter can quickly ensure the desired control performance without experiencing singularity problems. In this scheme, the chattering effects are minimised by replacing the discontinuous function appearing in the control law with a continuous function and the Lyapunov stability theory is utilised to demonstrate the theoretical stability of the control law. This paper also includes an overview of the non‐singular terminal sliding model controller as the performance of the non‐singular fast terminal sliding model controller is compared with this controller through rigorous simulation results over a range of fault currents. Simulation results clearly demonstrate the faster convergence speed of the non‐singular fast terminal sliding model controller over the non‐singular terminal sliding model controller for compensating the fault current and hence, mitigating powerline bushfires.
Upping the internal quantum efficiency of green light‐emitting diodes by employing a graded AlGaN barrier and an electron blocking layer
Authors: Usman Muhammad , Anwar Abdur‐Rehman , Munsif Munaza , Ullah Ihsan 
Published: January 2021

AbstractTwo different device structures are numerically studied, and their optoelectronic characteristics with standard structure are compared. The authors minimized the uneven carrier distribution across the active region. By replacing the first quantum barrier with graded AlGaN and using a graded AlGaN electron blocking layer, in the structure proposed by the authors, the injection of holes into the active region is improved. By using the graded AlGaN barrier, the concentration of injected electrons is also controlled because of the additional barrier height. As a result, the contribution of radiative recombination is boosted. The droop ratio of the proposed structure is reduced to ∼34% at 100 A cm−2 in comparison to other devices.
Parker Solar Probe observations of He/H abundance variations in SEP events inside 0.5 au
Authors: Cohen C. M. S. , Christian E. R. , Cummings A. C. , Davis A. J. , Desai M. I. , de Nolfo G. A. , Giacalone J. , Hill M. E. , Joyce C. J. , Labrador A. W. , Leske R. A. , Matthaeus W. H. , McComas D. J. , McNutt R. L. , Mewaldt R. A. , Mitchell D. G. , Mitchell J. G. , Rankin J. S. , Roelof E. C. , Schwadron N. A. , Stone E. C. , Szalay J. R. , Wiedenbeck M. E. , Vourlidas A. , Bale S. D. , Pulupa M. , MacDowall R. J. 
Published: January 2021

Aims. The Parker Solar Probe (PSP) orbit provides an opportunity to study the inner heliosphere at distances closer to the Sun than previously possible. Due to the solar minimum conditions, the initial orbits of PSP yielded only a few solar energetic particle (SEP) events for study. Recently during the fifth orbit, at distances from 0.45 to 0.3 au, the energetic particle suite on PSP, Integrated Science Investigation of the Sun (IS⊙IS), observed a series of six SEP events, adding to the limited number of SEP events studied inside of 0.5 au. Variations in the H and He spectra and the He/H abundance ratio are examined and discussed in relation to the identified solar source regions and activity.
Methods. IS⊙IS measures the energetic particle environment from ~20 keV to >100 MeV/nuc. Six events were selected using the ~1 MeV proton intensities, and while small, they were sufficient to calculate proton and helium spectra from ~1 to ~10 MeV/nuc. For the three larger events, the He/H ratio as a function of energy was determined. Using the timing of the associated radio bursts, solar sources were identified for each event and the eruptions were examined in extreme ultraviolet emission.
Results. The largest of the selected events has peak ~1 MeV proton intensities of 3.75 (cm2 sr s MeV)−1. Within uncertainties, the He and H spectra have similar power law forms with indices ranging from −2.3 to −3.3. For the three largest events, the He/H ratios are found to be relatively energy independent; however, the ratios differ substantially with values of 0.0033 ± 0.0013, 0.177 ± 0.047, and 0.016 ± 0.009. An additional compositional variation is evident in both the 3He and electron signatures. These variations are particularly interesting as the three larger events are likely a result of similar eruptions from the same active region.
Giant planet migration during the disc dispersal phase
Authors: Monsch Kristina , Picogna Giovanni , Ercolano Barbara , Kley Wilhelm 
Published: January 2021

Context. Transition discs are expected to be a natural outcome of the interplay between photoevaporation and giant planet formation. Massive planets reduce the inflow of material from the outer to the inner disc, therefore triggering an earlier onset of disc dispersal due to photoevaporation through a process known as Planet-Induced PhotoEvaporation. In this case, a cavity is formed as material inside the planetary orbit is removed by photoevaporation, leaving only the outer disc to drive the migration of the giant planet.
Aims. We investigate the impact of photoevaporation on giant planet migration and focus specifically on the case of transition discs with an evacuated cavity inside the planet location. This is important for determining under what circumstances photoevaporation is efficient at halting the migration of giant planets, thus affecting the final orbital distribution of a population of planets.
Methods. For this purpose, we use 2D FARGO simulations to model the migration of giant planets in a range of primordial and transition discs subject to photoevaporation. The results are then compared to the standard prescriptions used to calculate the migration tracks of planets in 1D planet population synthesis models.
Results. The FARGO simulations show that once the disc inside the planet location is depleted of gas, planet migration ceases. This contradicts the results obtained by the impulse approximation, which predicts the accelerated inward migration of planets in discs that have been cleared inside the planetary orbit.
Conclusions. These results suggest that the impulse approximation may not be suitable for planets embedded in transition discs. A better approximation that could be used in 1D models would involve halting planet migration once the material inside the planetary orbit is depleted of gas and the surface density at the 3:2 mean motion resonance location in the outer disc reaches a threshold value of 0.01 g cm‒2.
Ballot position effects in open-list PR systems: the moderating impact of postal voting
Authors: Jankowski Michael , Frank Torren 
Published: January 2021

AbstractVarious studies demonstrate that candidates at the top of the party list have a strong advantage in preferential voting systems, particularly under open-list PR. Such ballot position effects can be explained by voters’ tendency to rely on easily available information shortcuts when selecting a candidate. In this paper, we argue that the strength of ballot position effects depends on the context of how voters cast their vote. Specifically, we argue that postal voters are less likely to rely on the ballot position cue compared to voters who vote on election day for two reasons. First, postal voters might be more politically interested. Second, postal voters have more time to assess additional information about the candidates. The hypothesis is tested by analyzing newly collected data from two open-list PR elections in the German federal state of Hamburg. The results confirm the theoretical expectations: Ballot position effects are substantively weaker among postal voters. Additional analyses suggest that differences in the political interest between postal voters and election day voters are unlikely to fully explain these results. These findings advance our understanding of ballot position effects and voters’ use of information shortcuts more generally.
Acousto-optical analogue of a Fabry – Perot resonator
Authors: Pustovoit V.I. 
Published: January 2021

Abstract
A new method is proposed to increase the spectral resolving power of collinear acousto-optical filters by using optical feedback when the light leaving the region of its interaction with a periodic structure formed in the crystal by an acoustic wave returns to the input of the crystal, in which the diffraction process repeats itself many times. The light beam returned to the interaction region changes the boundary conditions of the parametric diffraction problem, because of which the amplitudes of the diffracted and passed light beams turn out to be strongly dependent on the feedback properties (similar to the processes occurring in a Fabry – Perot optical resonator). It is shown that such a combined acousto-optical Fabry – Perot filter with feedback is able to electronically tune the optical transmission wavelength and simultaneously has a higher spectral resolution than a conventional acousto-optical filter without feedback. It is also shown that the multiple radiation diffraction due to the feedback increases the diffraction efficiency with a comparatively small spatial change in the refractive index of the medium. Explicit analytical expressions for the instrumental functions of a combined acousto-optical Fabry – Perot filter are found and their properties are analysed. It is noted that a change in the feedback by any mechanism, i.e., by changing the returned wave phase or amplitude, leads to modulation of the measured signal, which makes it possible to create more precise methods of spectral measurements.
Analysis of the pulse waveform in arterial vessels using the spectrum of the autodyne signal of a laser interferometer
Authors: Skripal An.V. , Dobdin S.Yu. , Dzhafarov A.V. , Chernetsova I.A. 
Published: January 2021

Abstract
The results of measuring the derivative of the pulse wave using a laser autodyne based on the Fourier analysis of the low-frequency spectrum of the interference signal are presented. The features of using the windowed Fourier transform for window types and window widths are discussed. The correlation coefficient between the derivative obtained by direct differentiation of the sphygmographic signal and the frequency dependence of the windowed Fourier transform obtained from the analysis of the interference signal is calculated. It is shown that the amplitude of biovibration of the skin surface has the greatest influence on the correlation of the frequencies of the window spectrum of the autodyne signal with direct measurements of the pulse wave parameters by the sphygmographic method. Using a hardware-software system, we measured the sphygmogram of the pulse wave in the radial artery in a 19-year-old man who did not suffer from cardiovascular diseases. The derivative of the pulse wave obtained from the sphygmogram was compared with the dependence of the frequencies of the window spectrum of the autodyne signal. A comparative analysis of the dependences of the frequencies of the spectral harmonics of the window method with the derivative of the sphygmographic pulse showed a good correlation at the amplitudes of biovibration of the skin surface exceeding 10 μm.
Fast method for computer simulation of luminescence characteristics of multilayer biological tissues with embedded luminescent nanoparticles
Authors: Yakovlev D.D. , Sagaidachnaya E.A. , Yakovlev D.A. , Kochubey V.I. 
Published: January 2021

Abstract
We report a fast and computationally stable method for computer simulation of optical properties of layered scattering systems containing luminescent layers. The method is based on the solution of one-dimensional scalar radiative transfer equations and makes it possible to calculate spectral and angular characteristics of luminescent radiation emerging from the system under various conditions of luminescence excitation. The method is used to estimate the parameters necessary for determining temperature in subcutaneous layers from luminescence spectra of up-conversion nanoparticles embedded in these layers during transcutaneous optical probing.
Mammal species occupy different climates following the expansion of human impacts
Authors: Pineda-Munoz Silvia , Wang Yue , Lyons S. Kathleen , Tóth Anikó B. , McGuire Jenny L. 
Published: January 2021

Significance
Mammals on landscapes within North America are now living in different climates than they did prior to major human expansions. Many smaller animals have expanded into climates now dominated by agricultural and urban regions; whereas large-bodied mammals were forced out of these climates and were relegated to colder, dryer regions. As a result, the distributions of modern mammals do not accurately reflect the range of climatological conditions where species can live. Rather, they reflect the marginalization or facilitation that those species have undergone following the expansion of major human activities. Failing to mitigate the ecological changes that mammals are experiencing can have unprecedented impacts on the future survival of the remaining large-bodied species in North America.
Kallikrein directly interacts with and activates Factor IX, resulting in thrombin generation and fibrin formation independent of Factor XI
Authors: Kearney Katherine J. , Butler Juliet , Posada Olga M. , Wilson Clare , Heal Samantha , Ali Majid , Hardy Lewis , Ahnström Josefin , Gailani David , Foster Richard , Hethershaw Emma , Longstaff Colin , Philippou Helen 
Published: January 2021

Significance
Prekallikrein (PK) is a zymogen that is converted to kallikrein (PKa) by factor (F)XIIa. PK and FXII reciprocally activate each other; the resulting FXIIa initiates activation of the coagulation system via the cleavage of FXI to FXIa, which then activates FIX. This manuscript describes a novel high-affinity binding interaction between FIX(a) and PK(a) and reports that PKa can dose- and time-dependently activate FIX to generate FIXa, resulting in thrombin generation and clot formation independent of FXIa. Characterization of the kinetics of FIX activation reveal that PKa is a more significant activator of FIX than previously considered. This work highlights a new amendment to the coagulation cascade where PKa can directly activate FIX.