bluuebunny/crossref_metadata_2025 huggingface dataset:
Probing the thermodynamic conditions of the heliosheath plasma by shock wave propagation
Authors: Fahr H. J. , Heyl M.
Published: August 2020

Context. The pressure equilibrium between the inner heliosheath and the outer heliosheath (referred to as the local interstellar medium) is an eminent theoretical and practical problem; theoretical, because the relevant pressure carriers have to be identified, and practical, because data must be gathered in order to confirm such a pressure equilibrium. The problem is closely connected with the stability of the heliopause, that is, of the tangential discontinuity between these two counterflowing media, and is of utmost importance for understanding the stability of the whole circumsolar plasma structure.

Aims. In this paper we analyze the thermodynamic conditions of the multi-fluid plasma between the solar wind termination shock and the heliopause determining the total heliosheath pressure. We look into this problem from a theoretical standpoint and revisit theoretical descriptions of the solar wind plasma after its passage over the solar wind termination shock, thereafter forming the subsonic heliosheath region.

Methods. Hereby we take into account the 3D magnetohydrodynamics shock conditions and the resulting 3D temperature structure of the downstream plasma flow. We use a kind of seismological procedure to probe the heliosheath plasma by inquiring into the propagation conditions of traveling shock wave perturbations in this predetermined 3D heliosheath plasma structure. We discuss the fact that the front geometry of such a traveling shock wave most probably does not remain spherical, if it was to begin with, due to asymmetric shock propagation conditions. In contrast, the wave front is likely to become strongly deformed into an upwind bulge.

Results. Concerning the plasma pressure, in addition to solar wind and pick-up proton pressures, we have to take into account the solar wind electron pressure which as a surprise turns out to be of comparable magnitude. As a consequence, the characteristic propagation speed of the traveling shock wave in the weakly magnetized heliosheath plasma is given as a mixed speed expressed by the sound speeds of the protons and the electrons. We describe local low-energy proton density signatures that can be found in Voyager-2 proton data as a consequence of traveling shock wave passages and show that the total local plasma pressure can be directly derived from them.
A fixed point algorithm for improving fidelity of quantum gates
Authors: Pereira da Silva Paulo Sergio , Rouchon Pierre , Silveira Hector Bessa
Published: August 2020

This work considers the problem of quantum gate generation for controllable quantum systems with drift. It is assumed that an approximate solution called seed is pre-computed by some known algorithm. This work presents a method, called Fixed-Point Algorithm (FPA) that is able to improve arbitrarily the fidelity of the given seed. When the infidelity of the seed is small enough and the approximate solution is attractive in the context of a tracking control problem (that is verified with probability one, in some sense), the Banach Fixed-Point Theorem allows to prove the exponential convergence of the FPA. Even when the FPA does not converge, several iterated applications of the FPA may produce the desired fidelity. The FPA produces only small corrections in the control pulses and preserves the original bandwidth of the seed. The computational effort of each step of the FPA corresponds to the one of the numerical integration of a stabilized closed loop system. A piecewise-constant and a smooth numerical implementations are developed. Several numerical experiments with a N-qubit system illustrates the effectiveness of the method in several different applications including the conversion of piecewise-constant control pulses into smooth ones and the reduction of their bandwidth.
Studying of parameters of two-phase displacement in porous media with MRI technique
Authors: Fannir Jamal , Panfilova Irina , Leclerc Sébastien , Stemmelen Didier
Published: August 2020

This study describes experimental research on two-phase flow displacement using Magnetic Resonance Imaging (MRI) techniques. The overall purpose of this investigation is to determine kinetics process of phase trapping during (water-oil) two-phase flow, the front deformation and the phases saturation propagation along a vertical model. In these water flooding experiments, the porous medium model consists of packed beads of polystyrene (0.4 mm < dp < 0.6 mm) or sand grains (0.02 mm < dp < 0.50 mm). In order to conduct high accuracy experiments, a Nuclear Magnetic Resonance (NMR) spectrometer operating at 14 T (corresponding to a 600 MHz 1H resonance) equipped with an imaging device was used. With this equipment we can measure and visualize the two-phase flow in a vertical model of porous medium under ambient conditions. The obtained results have shown that the oil saturation profile is strongly influenced by the material properties such as the phase wetting, the sample porosity and permeability as well as the injection rate. The influence of flow velocity on the residual oil saturation was also studied. The experimental results allow an essential understanding of immiscible fluid displacement in two different types of porous medium that differ from each other mainly by the effects of wettability.
Analysis of threat based algorithm using different performance measures
Authors: Ahmad Iftikhar , Pirron Marcus , Schmidt Günter
Published: August 2020

Since its introduction in 1985, competitive analysis is a widely used tool for the performance measurement of online algorithms. Despite its simplicity and popularity, competitive analysis has its own set of drawbacks which lead to the development of other performance measures. However, these measures were seldom applied to problems in other domains. Recently Boyar et al. (Theor. Comput. Sci. 532 (2014) 2–13) studied the online search problem using various performance analysis measures for non-preemptive algorithms. We extend the work by considering preemptive threat-based algorithms and evaluate it using competitive analysis, bijective analysis, average case and relative interval analysis. For competitive analysis, and average case analysis, our findings are in contrast with that of Boyar et al., whereas for bijective and relative interval analysis our findings complement that of Boyar et al.
Jeder Handgriff muss sitzen
Authors: Becker Petra
Published: August 2020

Im Notfall muss jeder Handgriff sitzen. Das gilt erst recht für Notfälle, bei denen sehr viele schwerverletzte Menschen eingeliefert werden. Um sich dafür zu rüsten, wurden am Klinikum Konstanz in einem realitätsnahen Szenario die Behandlungsabläufe im OP durchgespielt.
Einsatz von OP-Pflegenden in anderen Klinikbereichen
Authors: Vogel Kathrin
Published: August 2020

Ungewöhnliche Situation erfordern häufig außergewöhnliche Maßnahmen. Als im März aufgrund der Corona-Pandemie der OP-Betrieb vielerorts eingeschränkt wurde, beschloss deshalb die Uniklinik Münster, OP-Pflegende in anderen Klinikbereichen einzusetzen. Dieser zunächst unfreiwillige Blick über den Tellerrand entwickelte sich schnell zu einem Erfolgsmodell.
Predicting Maximal Lactate Steady State from Carminatti’s
Shuttle Run Test in Soccer Players
Authors: Carminatti Lorival José , Batista Bruna Nunes , da Silva Juliano Fernandes , Tramontin Artur Ferreira , Costa Vitor Pereira , de Lucas Ricardo Dantas , Borszcz Fernando Klitzke
Published: August 2020

The objective of the present study was to determine the validity of
Carminatti’s shuttle run incremental test–T-Car derived
parameters in estimating the maximal lactate steady state determined in
shuttle run format. Eighteen soccer players performed a T-Car test, and
several trials to determine the maximal lactate steady state. From T-Car
were derived the heart rate deflection point, peak speed, maximal heart rate
and parameters resulting from percentage of peak measures. The validity was
accessed by Bland-Altman plots, linear regressions, and two one-sided tests
of equivalence analysis. The results showed the speed at 80.4% of
T-Car peak speed, the heart rate deflection point and the 91.4% of
maximal heart rate were equivalent to maximal lactate steady state (Mean
difference; ±90% compatibility interval; −0.8;
±1.5%, −0.4; ±1.1%, and 0.0;
±2.7%, respectively). Additionally, peak speed during the
T-Car test was a stronger predictor of maximal lactate steady state (MLSS
[km/h]=2.57+0.65 × sPeak; r=0.82
[90% CI; 0.62–0.92], standard error of the
estimate=3.6%; 90% CI
×/÷1.4). Therefore, soccer players can use the T-Car
derived parameters as a noninvasive and practical alternative to estimate
the specific maximal lactate steady state for soccer.
Rowing Biomechanics, Physiology and Hydrodynamic: A Systematic
Review
Authors: Yusof Ab Aziz Mohd , Harun Muhamad Noor , Nasruddin Fakhrizal Azmi , Syahrom Ardiyansyah
Published: August 2020

According to numerous studies, rowing performance is influenced by several
factors including rower’s biomechanics, rower’s physiology, the
force generated and stroke style. However, there is a missing gap linking such
factors with rowing performance in the available literature. This paper aims to
investigate the rowing mechanism in terms of rower anthropometry and physiology,
which can impact its biomechanics and performance. The corresponding
hydrodynamic force generated by the oar blade to accelerate the boat is also
considered in the current study. To test the objectives, systematical online
searching was conducted in search of the inclusion literature criteria. All
included studies used Preferred Reporting item for Systematic Review and
Meta-analysis (PRISMA) guidelines to obtain the final collection of articles for
this review. In order to rate the quality of the articles, risk bias assessment
was performed. A total of 35 studies were included in the assessment. The
studies discussed the aspects of anthropometry and physiological of the rower,
the biomechanics of the rower, corresponding hydrodynamic force on the oar blade
and the rowing mechanism concerning boat performance. Based on the information
obtained, an understanding of the important aspects of the rowing mechanism was
achieved to provide an update for comprehensive improvement.
A Catalyst-Free, Temperature-Driven One-Pot Synthesis of 1-Adamantylhydrazine Hydrochloride
Authors: Bossmann Stefan H. , Delpe Acharige Anjana , Neri Raul , Hodgson James
Published: August 2020

1-Adamantylhydrazine can be a versatile intermediate for many biologically active compounds as adamantyl possesses a wide spectrum of medicinal properties. Described here is a detailed one-pot synthesis of 1-adamantylhydrazine, carried out on a milligram to gram scale, that steadily delivers a highly stable product used to carry out the synthesis of 1-(adamantan-1-yl)-1H-pyrazol-3-amine for bacterial studies. The reaction employs inexpensive, catalyst free, readily available starting materials. In the synthesis of 1-(adamantan-1-yl)-1H-pyrazol-3-amine, the use of a continuous extraction method allows for complete extraction of the target product into the organic layer and increases the overall percentage yield.
Hyperkinetic Seizures with Ictal Fear as Localizing Ictal Signs in MRI-Negative Medial Frontal Lobe Epilepsy
Authors: Cloppenborg Thomas , Albers Kristina , Kalbhenn Thilo , Woermann Friedrich G. , Bien Christian G. , Polster Tilman
Published: August 2020

Purpose Hyperkinetic seizures are described as seizure onset in the frontal or temporal lobe. Additional localizing information is important for diagnostic workup and surgical therapy. We describe diagnostic workup and surgical outcomes in three patients with pharmacoresistant focal emotional seizures with hyperkinetic elements.

Methods/Results High-resolution 3 Tesla (T) magnetic resonance imaging (MRI) did not reveal clear-cut lesions. Invasive video-electroencephalography (EEG) with depth electrodes along the cingulate sulcus (bilateral; patients 1 and 3), right; patient 2 provided congruent results for a circumscribed seizure onset zone within the medial frontal lobe (right: patients 1 and 2; left: patient 3). Topectomies were performed in all patients. Histopathology revealed a small focal cortical dysplasia in the three cases (focal cortical dysplasia [FCD] IIA: patient 1; FCD IIB: patients 2 and 3). All patients remained completely seizure-free since surgery (Engel 1A; follow-up: 9–28 months).

Conclusion Ictal fear associated with hyperkinetic semiology points to a seizure-onset zone within the anteromedial frontal lobe (anterior cingulate gyrus). Ictal semiology is crucial for the placement of depth electrodes, especially in MRI-negative cases. These cases illustrate a clinical advantage to the new International League against Epilepsy (ILAE) seizure classification, emphasizing initial clinical symptoms.
Supply control vs. demand control: why is resource tax more effective than carbon tax in reducing emissions?
Authors: Lin Boqiang , Jia Zhijie
Published: August 2020

Carbon tax and some other policies are designed to reduce emissions; resource tax can raise the energy price from the supply side to achieve the purpose of emission mitigation. Based on previous studies, this paper abstracts mitigation policies into supply-control (resource tax as an example) and demand-control (carbon tax as an example). The effects of these policies have been divided into the direct and the indirect effects. A dynamic recursive computable general equilibrium model is applied to simulate different impact path of the two policies. The research shows that if there is no foreign trade and the market is completely market-oriented, the effect of the demand control and the supply control may be equivalent. But this is not the real case. Under the same level of CO2 emission, carbon tax can significantly reduce the energy demand of enterprises and restrain energy imports. However, resource tax can significantly increase domestic energy prices firstly, and then enterprises will be more willing to use cheaper imported energy. Regardless of energy security, relatively low energy use costs ease the economic costs of emission mitigation. Therefore, if every country in the world is required to reduce emissions compulsorily, resource tax may be a better policy of reducing emissions while obtaining “excess profits”.
Invariant tori for a class of singly thermostated Hamiltonians
Authors: Butler Leo T.
Published: August 2020

This paper demonstrates sufficient conditions for the existence of a positive measure set of invariant KAM (Kolmogrov-Arnol'd-Moser) tori in a singly thermostated, one degree-of-freedom Hamiltonian vector field. This result is applied to four important single thermostats in the literature, and it is shown that in each case, if the Hamiltonian is real-analytic and well-behaved, then the thermostated system always has a positive measure set of invariant KAM tori for sufficiently weak coupling and high temperature. This extends the results of Legoll, Luskin, and Moeckel [Arch. Ration. Mech. Anal. 184, 449 (2007)] and Legoll et al. [Nonlinearity 44, 1673 (2009)].
Requirements for a 4ω Thomson scattering system on megajoule scale laser facilities
Authors: Depierreux S. , Tassin V. , Neuville C. , Katz J.
Published: August 2020

With the arrival of megajoule class laser facilities, the features of laser-produced plasmas are evolving toward unprecedented high electron temperatures reached in the environment of a cm-scale indirect-drive Hohlraum for a few tens of nanoseconds. In this context, the need for in situ experimental characterization of the plasma parameters becomes critical in order to test hydrodynamics simulations in these novel conditions. Taking advantage of the progress achieved in the last 40 years, Thomson scattering has become a classic diagnostic in the characterization of laser produced plasmas. However, the many beam configuration of the megajoule scale experiments makes the measurements increasingly complex because the Thomson scattering signals produced by the 351 nm heaters themselves dominate the plasma emission around 263 nm, a wavelength range typically of interest when a 4ω Thomson probe is used. This paper reviews the requirements for and the potential of a 4ω Thomson scattering system to be operated on such 351 nm megajoule scale facilities in order to characterize the hot (Te > 3 keV) plasmas produced in the indirect-drive irradiation of a Hohlraum. It is found that the configuration of the diagnostic could be optimized in order to enable the detection of the ion acoustic resonances over a large domain of plasma parameters. The results for the electron plasma wave resonances are also given.
An origami-inspired dynamically actuated binary switch
Authors: Masana R. , Khazaaleh S. , Alhussein H. , Crespo R. S. , Daqaq M. F.
Published: August 2020

Origami, the ancient Japanese art of folding paper to create esthetic sculptures, has recently emerged in the scientific literature as an innovative means to build mechanical structures with tailorable properties. Along those lines, the Kresling origami pattern has been used to design and construct bi-stable bellows with tailorable stiffness. In this work, we exploit the inter-well dynamic behavior of such bellows to develop and characterize a cluster of mechanical binary switches that can be selectively operated using a single input. This input is in the form of a harmonic resonant excitation with a pre-selected frequency and magnitude applied at the base of the switch. Using a phenomenological model of the switch, we study its nonlinear dynamic behavior and approximate its activation frequency bandwidth. We also demonstrate that multiple binary switches of different geometric characteristics can be combined to create a mechanical memory board of multiple bits placed on a single harmonically excited platform.
Multi-mode metamaterial-inspired resonator for near-field wireless power transfer
Authors: Song Mingzhao , Smirnov Pavel , Puhtina Ekaterina , Zanganeh Esmaeel , Glybovski Stanislav , Belov Pavel , Kapitanova Polina
Published: August 2020

The modern development of wireless power transfer (WPT) technologies brings various products that improve the lives of users. It has become an urgent demand to simultaneously charge multiple mobile devices operating under different WPT standards on a charging platform regardless of their position and orientation with respect to each other. Recent advances in metasurfaces make it possible to control the near electromagnetic fields with much more degrees of freedom in comparison to conventional resonators. Here, we develop a compact multi-mode metamaterial-inspired resonator formed as an array of sub-wavelength parallel strip conductors. This resonator aims to replace conventional flat coil resonators and offers multiple modes with different profiles of electromagnetic field distribution for various near-field WPT applications. The first three eigenmodes are numerically and experimentally studied, and their potential applications for design of multi-mode WPT systems capable of charging multiple receivers simultaneously are discussed.
On the high–low method for NLS on the hyperbolic space
Authors: Staffilani Gigliola , Yu Xueying
Published: August 2020

In this paper, we first prove that the cubic, defocusing nonlinear Schrödinger equation on the two dimensional hyperbolic space with radial initial data in Hs(H2) is globally well-posed and scatters when s > 3/4. Then, we extend the result to nonlinearities of order p > 3. The result is proved by extending the high–low method of Bourgain in the hyperbolic setting and by using a Morawetz type estimate proved by Staffilani and Ionescu.
Optimization of the Reax force field for the lithium–oxygen system using a high fidelity charge model
Authors: O’Hearn Kurt A. , Swift Michael W. , Liu Jialin , Magoulas Ilias , Piecuch Piotr , van Duin Adri C. T. , Aktulga H. Metin , Qi Yue
Published: August 2020

Studies using molecular dynamics (MD) have long struggled to simulate the failure modes of materials, predicting unrealistically high ductility and failing to capture brittle fracture. The primary cause of this shortcoming is an inadequate description of bond breaking. While reactive force fields such as ReaxFF show improvements compared to traditional force fields, the charge models used yield unphysical partial charges, especially during dissociation of ionic bonds. This flaw may be remedied by using the atom-condensed Kohn–Sham density functional theory (DFT) approximated to a second order (ACKS2) charge model for determining partial charges. In this work, we present a new ACKS2-enabled Reax force field for fracture simulations of lithium oxide systems, which was obtained by training against an extensive set of DFT, multireference configuration interaction (MRCI), and MRCI+Q reference data using genetic optimization techniques. This new force field significantly improves the bond breaking behavior, but still cannot fully capture the brittle fracture in MD simulations, suggesting more research is needed to improve simulation of brittle fracture.
Elliptic supersonic jet morphology manipulation using sharp-tipped lobes
Authors: Rao Srisha M. V. , Karthick S. K. , Anand Abhinav
Published: August 2020

Elliptic nozzle geometry is attractive for mixing enhancement of supersonic jets. However, jet dynamics, such as flapping, gives rise to high-intensity tonal sound. We experimentally manipulate the supersonic elliptic jet morphology by using two sharp-tipped lobes. The lobes are placed on either end of the minor axis in an elliptic nozzle. The design Mach number and the aspect ratio of the elliptic nozzle and the lobed nozzle are 2.0 and 1.65. The supersonic jet is exhausted into ambient under almost perfectly expanded conditions. Time-resolved schlieren imaging, longitudinal and cross-sectional planar laser Mie scattering imaging, planar Particle Image Velocimetry (PIV), and near-field microphone measurements are performed to assess the fluidic behavior of the two nozzles. Dynamic Mode Decomposition (DMD) and proper orthogonal decomposition analyses are carried out on the schlieren and the Mie scattering images. Mixing characteristics are extracted from the Mie scattering images through the image processing routines. The flapping elliptic jet consists of two dominant DMD modes, while the lobed nozzle has only one dominant mode, and the flapping is suppressed. Microphone measurements show the associated noise reduction. The jet column bifurcates in the lobed nozzle enabling a larger surface contact area with the ambient fluid and higher mixing rates in the near-field of the nozzle exit. The jet width growth rate of the two-lobed nozzle is about twice that of the elliptic jet in the near-field, and there is a 40% reduction in the potential core length. PIV contours substantiate the results.
Formation of nanodiamond by pulsed discharge of carbon fiber wires
Authors: Gao Xin , Huang Kun , Tan Zhen , Wang Bi , Song Qiuzhi , Chen Qi , Chen Pengwan
Published: August 2020

High-crystalline nanodiamond powder was formed during pulsed discharge of carbon fiber wires in distilled water at room temperature. The copper-foil-encapsulated carbon fiber wires were also exploded to generate converging shockwaves with a higher pressure for the formation of nanodiamond. The recovered samples were characterized to be well crystallized nanodiamond with a quasi-spherical shape and a size of 3–10 nm mostly. The possible mechanism that governs the formation of nanodiamond (ND) was illustrated. Furthermore, the results show that a high input energy density of pulsed wire discharge is critical to the ND formation. The increase in the charge voltage and application of copper-foil pipe can improve the yields of ND up to 20%. This work provides an innovative route to synthesize ND through the pulsed wire discharge method and is conducive to the investigation and applications of extreme conditions induced by pulsed discharge.
Wavelet scattering networks for atomistic systems with extrapolation of material properties
Authors: Sinz Paul , Swift Michael W. , Brumwell Xavier , Liu Jialin , Kim Kwang Jin , Qi Yue , Hirn Matthew
Published: August 2020

The dream of machine learning in materials science is for a model to learn the underlying physics of an atomic system, allowing it to move beyond the interpolation of the training set to the prediction of properties that were not present in the original training data. In addition to advances in machine learning architectures and training techniques, achieving this ambitious goal requires a method to convert a 3D atomic system into a feature representation that preserves rotational and translational symmetries, smoothness under small perturbations, and invariance under re-ordering. The atomic orbital wavelet scattering transform preserves these symmetries by construction and has achieved great success as a featurization method for machine learning energy prediction. Both in small molecules and in the bulk amorphous LiαSi system, machine learning models using wavelet scattering coefficients as features have demonstrated a comparable accuracy to density functional theory at a small fraction of the computational cost. In this work, we test the generalizability of our LiαSi energy predictor to properties that were not included in the training set, such as elastic constants and migration barriers. We demonstrate that statistical feature selection methods can reduce over-fitting and lead to remarkable accuracy in these extrapolation tasks.
High harmonic optomechanical oscillations in the lithium niobate photonic crystal nanocavity
Authors: Jiang Haowei , Yan Xiongshuo , Liang Hanxiao , Luo Rui , Chen Xianfeng , Chen Yuping , Lin Qiang
Published: August 2020

We explore the optomechanical coupling in an on-chip lithium niobate (LN) photonic crystal nanocavity. A mechanical frequency shift and nonlinear mechanical oscillations are observed with the intracavity power increasing. A 14th harmonic oscillation is generated at the intracavity power of 430 μW in the LN photonic crystal, which potentially can function as a mechanical frequency comb. The photonic crystal structure also shows the positive temperature coefficient of frequency, while the LN crystal has a negative intrinsic temperature coefficient. These characters of optomechanics in LN may play important roles in photon-phonon coupling or detector systems such as sensitive displacement and the mass and force detection.
Anisotropic domains and antiferrodistortive-transition controlled magnetization in epitaxial manganite films on vicinal SrTiO3 substrates
Authors: Paudel Binod , Zhang Bruce , Sharma Yogesh , Kang Kyeong Tae , Nakotte Heinrich , Wang Haiyan , Chen Aiping
Published: August 2020

We studied the microstructural evolution and magnetism of ferroelastic La0.9Sr0.1MnO3 (LSMO) epitaxial thin films grown on SrTiO3 (001) substrates with different miscut angles. The substrate miscut angle plays a critical role in controlling the in-plane magnetic anisotropy. The microscopic origin of such magnetic anisotropy is attributed to the formation of anisotropic stripe domains along the surface step terraces. The magnetization in the LSMO films was found to be selectively modulated by the antiferrodistortive phase transition of the SrTiO3 substrate. This phenomenon has been qualitatively explained by a strain modified Stoner–Wohlfarth model. We conclude that the magnetization modulation by the SrTiO3 phase transition depends on h, the ratio of applied magnetic field to the saturation field. Such modulation is only visible with h < 1. The established domain microstructure–anisotropy–magnetism correlation in manganite films can be applied to a variety of complex oxide thin films on vicinal substrates.
Theoretical investigation of the H + HD → D + H2 chemical reaction for astrophysical applications: A state-to-state quasi-classical study
Authors: Bossion Duncan , Ndengué Steve , Meyer Hans-Dieter , Gatti Fabien , Scribano Yohann
Published: August 2020

We report a large set of state-to-state rate constants for the H + HD reactive collision, using Quasi-Classical Trajectory (QCT) simulations on the accurate H3 global potential energy surface of Mielke et al. [J. Chem. Phys. 116, 4142 (2002)]. High relative collision energies (up to ≈56 000 K) and high rovibrational levels of HD (up to ≈50 000 K), relevant to various non thermal equilibrium astrophysical media, are considered. We have validated the accuracy of our QCT calculations with a new efficient adaptation of the Multi Configuration Time Dependent Hartree (MCTDH) method to compute the reaction probability of a specific reactive channel. Our study has revealed that the high temperature regime favors the production of H2 in its highly rovibrationnally excited states, which can de-excite radiatively (cooling the gas) or collisionally (heating the gas). Those new state-to-state QCT reaction rate constants represent a significant improvement in our understanding of the possible mechanisms leading to the destruction of HD by its collision with a H atom.
Evolution of strong second-order magnetic anisotropy in Pt/Co/MgO trilayers by post-annealing
Authors: Gweon Hyung Keun , Lim Sang Ho
Published: August 2020

In this study, the first- (K1) and second-order (K2) magnetic anisotropies are investigated as a function of post-annealing temperature (Ta) in Pt/Co/MgO heterostructures. We find that both extrinsic and intrinsic mechanisms contribute to K2 with their relative contributions significantly depending on the quality of the Co/MgO interface, which is sensitively affected by the Ta value. In contrast with previous studies that mainly considered the extrinsic effects on K2, we obtain high K2 values of up to 2.04 × 106 erg/cm3 for the stack annealed at Ta = 400 °C by maximally utilizing the intrinsic effect at the Co/MgO interface, thus facilitating robust easy-cone anisotropy. We also demonstrate that the canted magnetization can be efficiently manipulated by the spin–orbit torques generated from the Pt layer, which is an important step toward the application of easy-cone states in various spintronic devices.
Multiple ESIPT pathways originating from three-state conical intersections in tropolone
Authors: Nag Probal , Vennapusa Sivaranjana Reddy
Published: August 2020

Internal conversion decay dynamics associated with the potential energy surfaces of three low-lying singlet excited electronic states, S1 (ππ*, A′), S2 (ππ*, A′), and S3 (nπ*, A″), of tropolone are investigated theoretically. Energetic and spatial aspects of conical intersections of these electronic states are explored with the aid of the linear vibronic coupling approach. Symmetry selection rules suggest that non-totally symmetric modes would act as coupling modes between S1 and S3 as well as between S2 and S3. We found that the S1–S2 interstate coupling via totally symmetric modes is very weak. A diabatic vibronic Hamiltonian consisting of 32 vibrational degrees of freedom is constructed to simulate the photoinduced dynamics of S0 → S1 and S0 → S2 transitions. We observe a direct nonadiabatic population transfer from S1 to S3, bypassing S2, during the initial wavepacket propagation on S1. On the other hand, the initial wavepacket evolving on S2 would pass through the S2–S3 and S1–S3 conical intersections before reaching S1. The presence of multiple proton transfer channels on the S1–S2–S3 coupled potential energy surfaces of tropolone is analyzed. Our findings necessitate the treatment of proton tunneling dynamics of tropolone beyond the adiabatic symmetric double well potentials.
Spin-controlled massive channels of hybrid-order Poincaré sphere beams
Authors: Zhang Yi-Heng , Chen Peng , Ge Shi-Jun , Wei Ting , Tang Jie , Hu Wei , Lu Yan-Qing
Published: August 2020

Featuring a nontrivial coupling between the orbital angular momentum of light and spatially inhomogeneous polarization, hybrid-order Poincaré sphere (HyOPS) beams have recently triggered numerous curiosities, especially in classical and quantum informatics. Despite much effort devoted to creating single HyOPS beam, it is still a formidable challenge to simultaneously harness multichannel and diverse HyOPS beams in a simple and efficient manner. Here, we propose a digitalized geometric phase optical element via photo-induced liquid crystal microstructures and demonstrate flexible and spin-controlled massive channels of HyOPS beams. By tuning the incident polarization, any state on up to 24 diverse HyOPSs is simultaneously mapped from common Poincaré sphere in high efficiency and good energy uniformity. All experimental results match well with the theoretical predictions of such a planar multifunctional device. This adds an extra spatial degree of freedom to advanced light tailoring and may facilitate parallel optical trapping, high-capacity communication, and high-dimensional quantum entanglement.
Hybrid CARS spectroscopy based on a high-repetition-rate all-PM-fiber laser source
Authors: Cao Tao , Yan Jikun , Chen Yu , Huang Le , Guo Ziyue , Liu Shaozhen , Hu Kailin , Ridsdale Andrew , Sokolov Alexei V. , Peng Jiahui
Published: August 2020

We demonstrate a robust, simple, and compact all polarization-maintaining (PM) fiber laser source with a repetition rate of 79 MHz for broadband coherent anti-Stokes Raman scattering (CARS) spectroscopy based on impulsive excitation and narrowband probing. The careful dispersion management during the generation of pump pulses ensures efficient impulsive excitation, which is verified to cover an ultrabroad bandwidth exceeding 4000 cm–1. The employment of PM fibers enables the laser source to withstand external disturbances. This turn-key configuration can potentially simplify the implementation of many applications of CARS, such as spectroscopic histopathology, weaponized endospore detection, and precise thermometry of gases.
Correlating the antisymmetrized geminal power wave function
Authors: Henderson Thomas M. , Scuseria Gustavo E.
Published: August 2020

Strong pairing correlations are responsible for superconductivity and off-diagonal long-range order in the two-particle density matrix. The antisymmetrized geminal power wave function was championed many years ago as the simplest model that can provide a reasonable qualitative description for these correlations without breaking number symmetry. The fact remains, however, that the antisymmetrized geminal power is not generally quantitatively accurate in all correlation regimes. In this work, we discuss how we might use this wave function as a reference state for a more sophisticated correlation technique such as configuration interaction, coupled cluster theory, or the random phase approximation.
Reopening dentistry after COVID-19: Complete suppression of aerosolization in dental procedures by viscoelastic Medusa Gorgo
Authors: Plog Jevon , Wu Jingwei , Dias Yasmin J. , Mashayek Farzad , Cooper Lyndon F. , Yarin Alexander L.
Published: August 2020

The aerosol transmissibility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has impacted the delivery of health care and essentially stopped the provision of medical and dental therapies. Dentistry uses rotary, ultrasonic, and laser-based instruments that produce water-based aerosols in the daily, routine treatment of patients. Abundant aerosols are generated, which reach health care workers and other patients. Viruses, including SARS-CoV-2 virus and related coronavirus disease (COVID-19) pandemic, continued expansion throughout the USA and the world. The virus is spread by both droplet (visible drops) and aerosol (practically invisible drops) transmission. The generation of aerosols in dentistry—an unavoidable part of most dental treatments—creates a high-risk situation. The US Centers for Disease Control and The Occupational Safety and Health Administration consider dental procedures to be of “highest risk” in the potential spreading of SARS-CoV-2 and other respiratory viruses. There are several ways to reduce or eliminate the virus: (i) cease or postpone dentistry (public and personal health risk), (ii) screen patients immediately prior to dental treatment (by appropriate testing, if any), (iii) block/remove the virus containing aerosol by engineering controls together with stringent personal protective equipment use. The present work takes a novel, fourth approach. By altering the physical response of water to the rotary or ultrasonic forces that are used in dentistry, the generation of aerosol particles and the distance any aerosol may spread beyond the point of generation can be markedly suppressed or completely eliminated in comparison to water for both the ultrasonic scaler and dental handpiece.
CAMSAP1 breaks the homeostatic microtubule network to instruct neuronal polarity
Authors: Zhou Zhengrong , Xu Honglin , Li Yuejia , Yang Mengge , Zhang Rui , Shiraishi Aki , Kiyonari Hiroshi , Liang Xin , Huang Xiahe , Wang Yingchun , Xie Qi , Liu Shuai , Chen Rongqing , Bao Lan , Guo Weixiang , Wang Yu , Meng Wenxiang
Published: August 2020

Significance

Proper formation of axon/dendrites is critical for the neuron to fulfill its function, and microtubules are the final performer in this process. However, how polarizing signals transduce to microtubules to instruct axon/dendrite differentiation remains unknown. Here we found that CAMSAP1, a microtubule minus-end binding protein, drives neuronal polarization, migration, and cortical lamination. We also demonstrate that the microtubule-binding ability of CAMSAP1 is critical for the protection of microtubule minus-ends and preservation of the “seeds” for microtubule regeneration, and this ability is regulated by MARK2. Thus, our findings reveal that CAMSAP1 controls neuronal polarization via triggering an unbalanced distribution of microtubules among neuronal processes; CAMSAP family members regulate axon formation by changing the quantity and quality of microtubules.
Global variability in seawater Mg:Ca and Sr:Ca ratios in the modern ocean
Authors: Lebrato Mario , Garbe-Schönberg Dieter , Müller Marius N. , Blanco-Ameijeiras Sonia , Feely Richard A. , Lorenzoni Laura , Molinero Juan-Carlos , Bremer Karen , Jones Daniel O. B. , Iglesias-Rodriguez Debora , Greeley Dana , Lamare Miles D. , Paulmier Aurelien , Graco Michelle , Cartes Joan , Barcelos e Ramos Joana , de Lara Ana , Sanchez-Leal Ricardo , Jimenez Paz , Paparazzo Flavio E. , Hartman Susan E. , Westernströer Ulrike , Küter Marie , Benavides Roberto , da Silva Armindo F. , Bell Steven , Payne Chris , Olafsdottir Solveig , Robinson Kelly , Jantunen Liisa M. , Korablev Alexander , Webster Richard J. , Jones Elizabeth M. , Gilg Olivier , Bailly du Bois Pascal , Beldowski Jacek , Ashjian Carin , Yahia Nejib D. , Twining Benjamin , Chen Xue-Gang , Tseng Li-Chun , Hwang Jiang-Shiou , Dahms Hans-Uwe , Oschlies Andreas
Published: August 2020

Significance

Seawater elemental composition, namely Mg:Ca and Sr:Ca ratios are widely used in marine sciences. Our new single-laboratory global dataset, combined with past data of seawater Mg:Ca and Sr:Ca ratios, suggests that modern ocean variability is significant across different environments, being similar to the changes during the Neogene Period (20 Ma). Because there is large variability in seawater ratios, we cannot assume that secular changes derived from fossilized taxa with varied ecological niches and from diverse ecosystems provide an unbiased representation of past global seawater chemistry. We suggest that the problem of inconsistencies in previous studies of, for example, paleo conditions from different fossil taxa may be reduced by accounting for taxonomic differences, ecosystems, and abiotic processes to overcome the regional environmental effect.
Robust paths to net greenhouse gas mitigation and negative emissions via advanced biofuels
Authors: Field John L. , Richard Tom L. , Smithwick Erica A. H. , Cai Hao , Laser Mark S. , LeBauer David S. , Long Stephen P. , Paustian Keith , Qin Zhangcai , Sheehan John J. , Smith Pete , Wang Michael Q. , Lynd Lee R.
Published: August 2020

Significance

The climate benefits of cellulosic biofuels have been challenged based on carbon debt, opportunity costs, and indirect land use change, prompting calls for withdrawing support for research and development. Using a quantitative ecosystem modeling approach, which explicitly differentiates primary production, ecosystem carbon balance, and biomass harvest, we show that none of these arguments preclude cellulosic biofuels from realizing greenhouse gas mitigation. Our assessment illustrates how deliberate land use choices support the climate performance of current-day cellulosic ethanol technology and how technological advancements and carbon capture and storage addition could produce several times the climate mitigation potential of competing land-based biological mitigation schemes. These results affirm the climate mitigation logic of biofuels, consistent with their prominent role in many climate stabilization scenarios.
CHD8 dosage regulates transcription in pluripotency and early murine neural differentiation
Authors: Sood Sabina , Weber Christopher M. , Hodges H. Courtney , Krokhotin Andrey , Shalizi Aryaman , Crabtree Gerald R.
Published: August 2020

Significance

The chromatin remodelerCHD8is one of the most frequently mutated genes in autism spectrum disorder (ASD), but the mechanistic basis remains unclear. Here, we identify dosage-sensitive roles for CHD8 in the regulation of transcription and define CHD8’s role in regulating genome-wide accessibility. Importantly, we present new results that help to define the molecular function of CHD8 both in the context of pluripotency and in neural differentiation with implications for its role in ASD. By determining the execution point at which mutations inChd8might contribute to the disease, we hope to discover the potential for therapeutic approaches.
KMT5c modulates adipocyte thermogenesis by regulating
Trp53
expression
Authors: Zhao Qingwen , Zhang Zhe , Rong Weiqiong , Jin Weiwei , Yan Linyu , Jin Wenfang , Xu Yingjiang , Cui Xuan , Tang Qi-Qun , Pan Dongning
Published: August 2020

Significance

The thermogenic function of adipocytes relies on the activation of the thermogenic program that is coordinately modulated by an array of unique transcriptional and epigenetic regulators. Histone methylations represent an essential epigenetic mode of regulation in the establishment of tissue-specific gene expression. However, the role of H4K20 methylation in thermogenic adipocytes is not completely elucidated. Our paper revealed
Kmt5c
is involved in regulating the thermogenic program in adipose tissues. Adipocyte-specific
Kmt5c
KO mice demonstrate decreased expression of thermogenic genes and are prone to diet-induced obesity. The findings indicate that activation of methyltransferase activity of KMT5c might be a potential strategy for metabolic diseases.
Febrile temperature change modulates CD4 T cell differentiation via a TRPV channel-regulated Notch-dependent pathway
Authors: Umar Danish , Das Arundhoti , Gupta Suman , Chattopadhyay Somdeb , Sarkar Debayan , Mirji Gauri , Kalia Jeet , Arimbasseri Gopalakrishnan Aneeshkumar , Durdik Jeannine Marie , Rath Satyajit , George Anna , Bal Vineeta
Published: August 2020

Significance

Since fever is frequently a response to infection, immune responses likely occur commonly at fever temperatures. Are fever temperatures detected by immune cells, what molecular pathways are involved in this sensing, and what are the functional consequences? Our data show that CD4 T lymphocytes detect moderate fever temperature. A TRPV channel-mediated pathway involving Notch activation leads to a Th2 skewing of the effector T cell response. However, the antigen presenting dendritic cells that stimulate CD4 T cells, in turn, detect fever temperature and overproduce interleukin-12 to counter this Th2 skewing. The evolutionary genesis of these pathways and the functional consequences of this complex regulatory loop in specific infectious circumstances are, thus, likely to be of great interest.
The contribution of black carbon to global ice nucleating particle concentrations relevant to mixed-phase clouds
Authors: Schill Gregory P. , DeMott Paul J. , Emerson Ethan W. , Rauker Anne Marie C. , Kodros John K. , Suski Kaitlyn J. , Hill Thomas C. J. , Levin Ezra J. T. , Pierce Jeffrey R. , Farmer Delphine K. , Kreidenweis Sonia M.
Published: August 2020

Significance

The Earth’s climate is affected by the radiative properties of clouds. In clouds containing both supercooled water droplets and ice particles (mixed-phase clouds), cloud lifetime and albedo are affected by the presence of ice nucleating particles (INP). After decades of research, the importance of black carbon (BC) as an INP remains unresolved. In this work, we determined the contribution of BC to INP concentrations ([INP]) from real-world wildfires and prescribed burns. We found that BC does not contribute significantly to [INP] in near-field biomass burning plumes. These results were applied as parameterizations to global climate model output. Combined with previous work on diesel-engine exhaust, we find that BC does not contribute significantly to global [INP] relevant to mixed-phase clouds.
Mechanism for analogous illusory motion perception in flies and humans
Authors: Agrochao Margarida , Tanaka Ryosuke , Salazar-Gatzimas Emilio , Clark Damon A.
Published: August 2020

Significance

Most of the time, visual circuitry in our brains faithfully reports visual scenes. Sometimes, however, it can report motion in images that are in fact stationary, leading us to perceive illusory motion. In this study, we establish that fruit flies, too, perceive motion in the stationary images that evoke illusory motion in humans. Our results demonstrate how this motion illusion in flies is an artifact of the brain’s strategies for efficiently processing motion in natural scenes. Perceptual tests in humans suggest that our brains may employ similar mechanisms for this illusion. This study shows how illusions can provide insight into visual processing mechanisms and principles across phyla.
Animal body size distribution influences the ratios of nutrients supplied to plants
Authors: le Roux Elizabeth , van Veenhuisen Laura S. , Kerley Graham I. H. , Cromsigt Joris P. G. M.
Published: August 2020

Significance

Herbivores influence nutrient cycling by depositing feces across the landscape. Where herbivores go in the landscape is governed by factors such as food requirements and vulnerability to predation, traits that are related to body size. We show that mammals that differ in body size not only use the landscape differently but also differ in the amount of nitrogen relative to phosphorus that they release through their feces. This ensures that plants that grow in areas used by predominantly larger herbivores (such as areas of higher predation risk or areas of greater food availability) will receive lower amounts of fecal phosphorus relative to fecal nitrogen, potentially impacting plant nutrient availability. This finding is noteworthy considering the extinction bias toward larger animals.
Multiplexed conditional genome editing with Cas12a inDrosophila
Authors: Port Fillip , Starostecka Maja , Boutros Michael
Published: August 2020

Significance

CRISPR-Cas genome engineering has enabled scientists to modify the genome of the popular model organismDrosophila melanogasterwith unprecedented ease. However, so far only the CRISPR nuclease Cas9 has been used for this task. Additional nucleases could expand the genomic target space and facilitate modification of independent cell populations in the same organism. Here we describe genome editing with Cas12a inDrosophila. Cas12a recognizes target sites orthogonal to Cas9, can use compact arrays of crRNAs for multiplexed gene editing, and conditional expression leads to tissue-specific mutagenesis. We also show that a point mutant in Cas12a substantially increases editing rates. This work significantly expands the CRISPR toolbox inDrosophilaand will inform the development of similar systems in other organisms.