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The tunability of the optical properties of lead halide perovskite nanocrystals makes them highly appealing for applications. Halide anion exchange and quantum confinement enable tailoring of the band gap. For spintronics, the Landé g-factors of electrons and holes are essential. Using empirical tight-binding and k·pmethods, we calculate them for nanocrystals of all-inorganic lead halide perovskites CsPbX3(X= I, Br, Cl). The hole g-factor band gap dependence follows the universal law found for bulk perovskites, while for electrons, a considerable modification is predicted. Based on the k·panalysis, we conclude that this difference arises from the interaction of the bottom conduction band with the spin–orbit split electron states. These predictions are confirmed experimentally for electron and hole g-factors in CsPbI3nanocrystals in a glass matrix, measured by time-resolved Faraday ellipticity in a magnetic field at cryogenic temperatures.

Lead halide perovskite nanocrystals in a glass matrix are a promising platform for optoelectronic applications due to their excellent optical properties combined with outstanding stability against the environment. We reveal the potential of this system for spintronics by studying the electron spin properties of CsPb(Cl,Br)3nanocrystals in a fluorophosphate glass matrix. Using optical spin orientation and spin depolarization with a radio frequency field, we measure longitudinal spin relaxation time, T1, reaching several hundreds of microseconds at low temperatures. This time T1corresponds to a spin state with a small gfactor, which we attribute to a weakly exchange-coupled electron–hole pair with antiparallel spins.

The role of T cell receptor (TCR) diversity in infectious disease susceptibility is not well understood. We use a systems immunology approach on three cohorts of herpes zoster (HZ) patients and controls to investigate whether TCR diversity against varicella-zoster virus (VZV) influences the risk of HZ. We show that CD4+T cell TCR diversity against VZV glycoprotein E (gE) and immediate early 63 protein (IE63) after 1-week culture is more restricted in HZ patients. Single-cell RNA and TCR sequencing of VZV-specific T cells shows that T cell activation pathways are significantly decreased after stimulation with VZV peptides in convalescent HZ patients. TCR clustering indicates that TCRs from HZ patients co-cluster more often together than TCRs from controls. Collectively, our results suggest that not only lower VZV-specific TCR diversity but also reduced functional TCR affinity for VZV-specific proteins in HZ patients leads to lower T cell activation and consequently affects the susceptibility for viral reactivation.

We prove local solvability and stability for the inverse problem of recovering a complex-valued square integrable potential in the Sturm–Liouville equation on a finite interval from spectra of two boundary value problems with one common boundary condition. For this purpose we generalize classical Borg’s method to the case of multiple spectra.

Recently, Hsieh and Otto (2014) suggested that transport of the closed magnetic flux to the dayside reconnection region may be a key process which controls the reconfiguration of magnetotail during the substorm growth phase. We investigate this problem using global self‐consistent MHD simulations and confirm that magnetotail reconfiguration is essentially a 3‐D process which cannot be fully described based on 2‐D‐like tail evolution powered by the magnetic flux loading into the lobes. We found that near‐Earth return convection strength on the nightside is directly related to the intensity of dayside reconnection, which causes the formation of antisunward azimuthal pressure gradients that force plasma to flow toward the dayside magnetopause. This near‐Earth part of global convection develops immediately after the onset of dayside reconnection and reaches a quasi‐steady level in 10–15 min. Its magnitude exceeds the total sunward flux transport in the midtail plasma sheet at X≈−20REby an order of magnitude, causing significant amount (0.1–0.2 GWb) of closed magnetic flux to be removed from the near‐Earth plasma sheet during moderate substorm. In that region the Bzdepletion and current sheet thinning are closely related to each other, and the local Jy(Bz) relationship in the simulations matches reasonably well the power law expression found in the plasma sheet. In summary, global simulations confirm quantitatively that near‐Earth return convection is primarily responsible for the severe depletion of the closed magnetic flux in the plasma sheet, major tail stretching, and current sheet thinning in the near magnetotail at r< 15RE. Global MHD (LFM) simulations of magnetotail growth phase dynamics following north‐south IMF turningsReturn convection at r< 10REon the nightside is proportional to EKLand by an order of magnitude higher than in the midtail at X=− 20RERemoval of closed magnetic flux by return convection controls the major reconfiguration of near magnetotail during substorm growth phase

In this response, we address the three main comments by Tsurutani et al. (2018, http://doi.org/10.1002/2017JA024779) namely, unusually high plasma density, interplanetary magnetic field intensity, and fast storm recovery phase. The authors agree that there is room to improve the modeling by taking into account these comments and other aspects that were not fully explored during our initial work. We are already in the process of undertaking a more comprehensive modeling project. We welcome the comments by Tsurutani that have potential to improve modeling of extreme geomagnetic activityOur ongoing new modeling work includes an ensemble modeling approach to address input specification concernsThe latest inner magnetosphere models will be used to look at loss cone losses and EMIC wave growth rates in the future

There is a growing concern over possible severe societal consequences related to adverse space weather impacts on man‐made technological infrastructure. In the last two decades, significant progress has been made toward the first‐principles modeling of space weather events, and three‐dimensional (3‐D) global magnetohydrodynamics (MHD) models have been at the forefront of this transition, thereby playing a critical role in advancing our understanding of space weather. However, the modeling of extreme space weather events is still a major challenge even for the modern global MHD models. In this study, we introduce a specially adapted University of Michigan 3‐D global MHD model for simulating extreme space weather events with a Dstfootprint comparable to the Carrington superstorm of September 1859 based on the estimate by Tsurutani et. al. (2003). Results are presented for a simulation run with “very extreme” constructed/idealized solar wind boundary conditions driving the magnetosphere. In particular, we describe the reaction of the magnetosphere‐ionosphere system and the associated induced geoelectric field on the ground to such extreme driving conditions. The model setup is further tested using input data for an observed space weather event of Halloween storm October 2003 to verify the MHD model consistence and to draw additional guidance for future work. This extreme space weather MHD model setup is designed specifically for practical application to the modeling of extreme geomagnetically induced electric fields, which can drive large currents in ground‐based conductor systems such as power transmission grids. Therefore, our ultimate goal is to explore the level of geoelectric fields that can be induced from an assumed storm of the reported magnitude, i.e., Dst∼=−1600 nT. Global MHD simulation of extreme Carrington‐type space weather eventDiscuss reaction of magnetosphere‐ionosphere system to extreme drivingProvide results off extreme geomagnetically induced electric fields

This paper presents the results of research and development of two types diode structures based on wide bandgap 4H-SiC: drift step recovery diodes (DSRDs) and field emission diodes (FED). Diodes’ structure and manufacturing methods are reviewed. Diode’s characteristics were obtained (static current-voltage characteristics and capacitor-voltage characteristic, switching properties’ characteristics for DSRDs). Field emission 4H-SiC structures illustrated high (≥102 А/сm2) current densities at electric field intensity of approximately 10V/um. 4H-SiC DSRDs in the generator structure with a single oscillating contour allowed to form sub nanosecond impulses at a load 50 Ohm and 1,5-2kV amplitude for a single diode (current density at V=2kV J= 4•103 А/сm2),what is significantly higher than similar DSRD’s parameters obtained for silicon.

The evolutionary history of the bovid subfamily Antilopinae is unclear. Traditionally, this subfamily is subdivided into two tribes: Neotragini (dwarf antelopes) and Antilopini (gazelles and their relatives). Here, we report new sequences for the 12S and 16S rRNA genes in the enigmatic antilopine taxa Procapra gutturosaand Saiga tataricaand analyze the phylogenetic relationships of these taxa relative to other antilopines. Our study demonstrates the close affinity of the saiga antelope to Gazelladespite the conventional systematic allocation of Saigato the Caprinae subfamily. The second member of the Saigini tribe, Pantholops hodgsoni(Tibetan gazelle), falls within Caprinae. In all of our analyses, Procapra gutturosaoccupied a basal position in the Antilopinae clade or was a sister-group to the dwarf antelope Madoqua.This suggests early separation of Procaprafrom other antelopes.

We study the inverse problem of recovering the potential q(x) from the spectrum of the operator -y′′(x)+q(x)y(a),y(α)(0)=y(β)(1)=0,where α,β∈{0,1}and a∈[0,1]is an arbitrary fixed rational number. We completely describe the cases when the solution of the inverse problem is unique and non-unique. In the last case, we describe sets of iso-spectral potentials and provide various restrictions on the potential under which the uniqueness holds. Moreover, we obtain an algorithm for solving the inverse problem along with necessary and sufficient conditions for its solvability in terms of characterization of the spectrum.

The original version of the article unfortunately contained few errors under Preliminaries section. The corrected text is given below.