Role of dimensional crossover on spin-orbit torque efficiency in magnetic insulator thin films

Magnetic insulators (MIs) attract tremendous interest for spintronic applications due to low Gilbert damping and absence of Ohmic loss. Magnetic order of MIs can be manipulated and even switched by spin-orbit torques (SOTs) generated through spin Hall effect and Rashba-Edelstein effect in heavy metal/MI bilayers. SOTs on MIs are more intriguing than magnetic metals since SOTs cannot be transferred to MIs through direct injection of electron spins. Understanding of SOTs on MIs remains elusive, especially how SOTs scale with the film thickness. Here, we observe the critical role of dimensionality on the SOT efficiency by systematically studying the MI layer thickness dependent SOT efficiency in tungsten/thulium iron garnet (W/TmIG) bilayers. We first show that the TmIG thin film evolves from two-dimensional to three-dimensional magnetic phase transitions as the thickness increases, due to the suppression of long-wavelength thermal fluctuation. Then, we report the significant enhancement of the measured SOT efficiency as the thickness increases. We attribute this effect to the increase of the magnetic moment density in concert with the suppression of thermal fluctuations. At last, we demonstrate the current-induced SOT switching in the W/TmIG bilayers with a TmIG thickness up to 15 nm. The switching current density is comparable with those of heavy metal/ferromagnetic metal cases. Our findings shed light on the understanding of SOTs in MIs, which is important for the future development of ultrathin MI-based low-power spintronics

Spin transport and dynamic properties of two-dimensional spin-momentum locked states

Materials with spin-momentum locked surface or interface states provide an interesting playground for studying physics and application of charge-spin current conversion. To characterize their non-equilibrium magnetic and transport properties in the presence of a time-dependent external magnetic field and a spin injection from a contact, we introduce three macroscopic variables: a vectorial helical magnetization, a scaler helical magnetization, and the conventional magnetization. We derive a set of closed dynamic equations for these variables by using the spinor Boltzmann approach with the collision terms consistent with the symmetry of spin-momentum locked states. By solving the dynamic equations, we predict several intriguing magnetic and transport phenomena which are experimentally accessible, including magnetic resonant response to an AC applied magnetic field, charge-spin conversion, and spin current induced by the dynamics of helical magnetization

THE PERFORMANCE OF BDS RELATIVE POSITIONING USAGE WITH REAL OBSERVATION DATA

With the first phase of COMPASS/BeiDou-2 (BDS) completed, the assessment ofpositioning performance and the characterization of its system are analyzed andpresented. Pseudo-range and carrier phase measurements modulated on B1 and B2have been collected in Shanghai, from 00:00 to 24:00 on 28 December, 2012.Compared with GPS, visibility and measurement quality of BDS’s GEO, IGSO andMEO satellites are analyzed. DOP during the whole orbital period is also analyzedthe results demonstrate that BDS’s HDOP is better than GPS’s one, but VDOPopposite. Furthermore, the result of positioning is also presented and analyzed.Short baselines are estimated by standalone BDS and GPS’s carrier phasemeasurement, respectively, using 48 segmentations of observations during a wholeday (24 hours, each segmentation, is about 30 minutes observation). The analysis ofstatic relative positioning demonstrates that BDS could achieve to millimeter level,corresponding to GPS. Kinematic result is produced by double differenced carrierphase observations with the ambiguities fixed under the constraint of precise shortbaseline.The result shows that the centimeter accuracy could be achieved. Whencomparing the results of kinematic baseline solutions, performance of BDS is worsethan GPS on North and Up components, but oppositely on the component of East inthe kinematic baseline processing

THE PERFORMANCE OF BDS RELATIVE POSITIONING USAGE WITH REAL OBSERVATION DATA

With the first phase of COMPASS/BeiDou-2 (BDS) completed, the assessment ofpositioning performance and the characterization of its system are analyzed andpresented. Pseudo-range and carrier phase measurements modulated on B1 and B2have been collected in Shanghai, from 00:00 to 24:00 on 28 December, 2012.Compared with GPS, visibility and measurement quality of BDS’s GEO, IGSO andMEO satellites are analyzed. DOP during the whole orbital period is also analyzedthe results demonstrate that BDS’s HDOP is better than GPS’s one, but VDOPopposite. Furthermore, the result of positioning is also presented and analyzed.Short baselines are estimated by standalone BDS and GPS’s carrier phasemeasurement, respectively, using 48 segmentations of observations during a wholeday (24 hours, each segmentation, is about 30 minutes observation). The analysis ofstatic relative positioning demonstrates that BDS could achieve to millimeter level,corresponding to GPS. Kinematic result is produced by double differenced carrierphase observations with the ambiguities fixed under the constraint of precise shortbaseline.The result shows that the centimeter accuracy could be achieved. Whencomparing the results of kinematic baseline solutions, performance of BDS is worsethan GPS on North and Up components, but oppositely on the component of East inthe kinematic baseline processing

A heterozygous moth genome provides insights into herbivory and detoxification

How an insect evolves to become a successful herbivore is of profound biological and practical importance. Herbivores are often adapted to feed on a specific group of evolutionarily and biochemically related host plants1, but the genetic and molecular bases for adaptation to plant defense compounds remain poorly understood2. We report the first whole-genome sequence of a basal lepidopteran species, Plutella xylostella, which contains 18,071 protein-coding and 1,412 unique genes with an expansion of gene families associated with perception and the detoxification of plant defense compounds. A recent expansion of retrotransposons near detoxification-related genes and a wider system used in the metabolism of plant defense compounds are shown to also be involved in the development of insecticide resistance. This work shows the genetic and molecular bases for the evolutionary success of this worldwide herbivore and offers wider insights into insect adaptation to plant feeding, as well as opening avenues for more sustainable pest management.Minsheng You … Simon W Baxter … et al

The golden apple snail Pomacea canaliculata shifts primary production from benthic to pelagic habitats in simulated shallow lake systems

Biological invasions are among the most serious threats to ecosystems. The golden apple snail Pomacea canaliculata (Lamarck, 1822) is considered one of the top 100 worst invasive alien species in the world. These snails consume benthic primary producers, including submerged macrophytes, which may lead to an increase in nutrient concentration in the water, enhance growth of phytoplankton, and decrease growth of macrophytes, thereby shifting the primary production from benthic to pelagic habitats in shallow systems. To test this hypothesis, we conducted a short-term experiment with and without the invasive P. canaliculata in mesocosms with high abundance of the native submerged macrophyte Vallisneria natans (Lour.) Hara. Compared with snail-free control, the snail increased the concentrations of total nitrogen (TN), nitrate nitrogen (NO3-N), total and organic suspended solids (TSS and OSS), decreased the concentrations of soluble reactive phosphorous (SRP), but had no effect on total phosphorus (TP) and the TN:TP ratio. In addition, the snails decreased the biomass, leaf length and tiller number of V. natans, and decreased light intensity. Although snail presence did not change the biomasses of nanophytoplankton and picophytoplankton, it did increase the biomass of microphytoplankton leading to an increase in total phytoplankton biomass. Our study shows that P. canaliculata shifted primary production from benthic to pelagic habitats, altered the phytoplankton community size structure, and decreased water quality. The results add further evidence of negative ecosystem impacts of this invasive apple snail and call for its control in invaded shallow lake ecosystems

Upregulation of MAGEA4 correlates with poor prognosis in patients with early stage of esophageal squamous cell carcinoma

Esophageal cancer is a common type of cancer in the People’s Republic of China. Many genes have been reported to be linked with it. Melanoma antigen gene family A (MAGEA) genes are frequently highly expressed in various types of carcinoma. However, the specific role of MAGEA gene expression in esophageal squamous cell carcinoma (ESCC) still remains unclear. MAGEA4 is a member of MAGEA genes. We aimed to investigate the expression and prognosis of MAGEA4 expression in ESCC. MAGEA4 messenger RNA expression levels of 120 pairs of tumor and nontumor tissues of patients with ESCC were measured by quantitative real-time polymerase chain reaction. The results showed that MAGEA4 messenger RNA was significantly elevated in tumor tissues of patients with ESCC compared to nontumor ones. In addition, overexpression of MAGEA4 messenger RNA was significantly correlated with poorer overall survival (P=0.018) in early stage of patients with ESCC (I–IIA). In conclusion, MAGEA4 played an important role in the early stage of ESCC and overexpression of MAGEA4 was expected to become a potential prognostic marker for patients with early stage of ESCC

Active Ingredients of Epimedii Folium and Ligustri Lucidi Fructus Balanced GR/HSP90 to Improve the Sensitivity of Asthmatic Rats to Budesonide

This study aimed to investigate the possible molecular mechanisms of active ingredients of Epimedii Folium (EF) and Ligustri Lucidi Fructus (LLF) combined with Budesonide (Bun) in asthmatic rats. Rats were divided into 5 groups, including normal group, asthma model group, Bun group, group of active ingredients of EL and LLF (EL), and group of coadministration of Bun with EL (Bun&EL). The asthmatic model was prepared by ovalbumin sensitizing and challenging. Lymphocyte apoptosis, GR protein and binding, and the protein and mRNA of GRα, GRβ, and HSP90 were tested. The results showed that Bun&EL ① markedly increased lymphocyte apoptosis, GR and HSP90 protein, and GR binding in BALF and ② enhanced the expressions of GRα and HSP90 and the ratio of GRα to GRβ or to HSP90 both in protein and in mRNA levels in lung, ③ while decrease occurred in GRβ mRNA and the mRNA ratio of GRβ to HSP90 compared with asthma or Bun group. Moreover, there was a significant correlation between GRα and GRβ in protein level, or between GRα and HSP90 both in protein and in mRNA levels. EL may effectively enhance the sensitivity of asthmatic rats to Bun via balancing GR/HSP90. And these findings will be beneficial for the treatment of asthma in the future