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Objective: The study aims to investigate the relationship between amplitude modulation (AM) of EEG and anesthesia depth during general anesthesia. Methods: In this study, Holo-Hilbert spectrum analysis (HHSA) was used to decompose the multichannel EEG signals of 15 patients to obtain the spatial distribution of AM in the brain. Subsequently, HHSA was applied to the prefrontal EEG (Fp1) obtained during general anesthesia surgery in 15 and 34 patients, and the α-θ and α-δ regions of feature (ROFs) were defined in Holo-Hilbert spectrum (HHS) and three features were derived to quantify AM in ROFs. Results: During anesthetized phase, an anteriorization of the spatial distribution of AMs of α-carrier in brain was observed, as well as AMs of α-θ and α-δ in the EEG of Fp1. The total power (${\bm{P}}_{\bm{total}}$), mean carrier frequency ($\bm{M}{\bm{F}}_{\bm{C}}$) and mean amplitude frequency ($\bm{M}{\bm{F}}_{\bm{AM}}$) of AMs changed during different anesthesia states. Conclusion: HHSA can effectively analyze the cross-frequency coupling of EEG during anesthesia and the AM features may be applied to anesthesia monitoring. Significance: The study provides a new perspective for the characterization of brain states during general anesthesia, which is of great significance for exploring new features of anesthesia monitoring.

Although the relationship between anesthesia and consciousness has been investigated for decades, our understanding of the underlying neural mechanisms of anesthesia and consciousness remains rudimentary, which limits the development of systems for anesthesia monitoring and consciousness evaluation. Moreover, the current practices for anesthesia monitoring are mainly based on methods that do not provide adequate information and may present obstacles to the precise application of anesthesia. Most recently, there has been a growing trend to utilize brain network analysis to reveal the mechanisms of anesthesia, with the aim of providing novel insights to promote practical application. This review summarizes recent research on brain network studies of anesthesia, and compares the underlying neural mechanisms of consciousness and anesthesia along with the neural signs and measures of the distinct aspects of neural activity. Using the theory of cortical fragmentation as a starting point, we introduce important methods and research involving connectivity and network analysis. We demonstrate that whole-brain multimodal network data can provide important supplementary clinical information. More importantly, this review posits that brain network methods, if simplified, will likely play an important role in improving the current clinical anesthesia monitoring systems.

Perpendicular magnetic tunnel junctions (p-MTJs) switched utilizing bipolar electric fields have extensive applications in energy-efficient memory and logic devices. Voltage-controlled magnetic anisotropy linearly lowers the energy barrier of the ferromagnetic layer via the electric field effect and efficiently switches p-MTJs only with a unipolar behavior. Here, we demonstrate a bipolar electric field effect switching of 100 nm p-MTJs with a synthetic antiferromagnetic free layer through voltage-controlled exchange coupling (VCEC). The switching current density, ∼1.1 × 105A/cm2, is 1 order of magnitude lower than that of the best-reported spin-transfer torque devices. Theoretical results suggest that the electric field induces a ferromagnetic–antiferromagnetic exchange coupling transition of the synthetic antiferromagnetic free layer and generates a fieldlike interlayer exchange coupling torque, which causes the bidirectional magnetization switching of p-MTJs. These results could eliminate the major obstacle in the development of spin memory devices beyond their embedded applications.

ABSTRACTVarious kinds of cap structures, such as m7G, triphosphate groups, NAD and dpCoA, protect the 5′ terminus of RNA. The cap structures bond covalently to RNA and affect its stability, translation, and transport. The removal of the caps is mainly executed by Nudix hydrolase family proteins, including Dcp2, RppH and NudC. Numerous efforts have been made to elucidate the mechanism underlying the removal of m7G, triphosphate group, and NAD caps. In contrast, few studies related to the cleavage of the RNA dpCoA cap have been conducted. Here, we report the hydrolytic activity of Escherichia coliNudC towards dpCoA and dpCoA-capped RNA in vitro. We also determined the crystal structure of dimeric NudC in complex with dpCoA at 2.0 Å resolution. Structural analysis revealed that dpCoA is recognized and hydrolysed in a manner similar to NAD. In addition, NudC may also remove other dinucleotide derivative caps of RNA, which comprise the AMP moieties. NudC homologs in Saccharomyces cerevisiaeand Arabidopsis thalianaexhibited similar dpCoA decapping (deCoAping) activity. These results together indicate a conserved mechanism underpinning the hydrolysis of dpCoA-capped RNA in both prokaryotes and eukaryotes.

Voltage control of magnetic order is desirable for spintronic device applications, but 180° magnetization switching is not straightforward because electric fields do not break time-reversal symmetry. Ferrimagnets are promising candidates for 180° switching owing to a multi-sublattice configuration with opposing magnetic moments of different magnitudes. In this study we used solid-state hydrogen gating to control the ferrimagnetic order in rare earth–transition metal thin films dynamically. Electric field-induced hydrogen loading/unloading in GdCo can shift the magnetic compensation temperature by more than 100 K, which enables control of the dominant magnetic sublattice. X-ray magnetic circular dichroism measurements and ab initio calculations indicate that the magnetization control originates from the weakening of antiferromagnetic exchange coupling that reduces the magnetization of Gd more than that of Co upon hydrogenation. We observed reversible, gate voltage-induced net magnetization switching and full 180° Néel vector reversal in the absence of external magnetic fields. Furthermore, we generated ferrimagnetic spin textures, such as chiral domain walls and skyrmions, in racetrack devices through hydrogen gating. With gating times as short as 50 μs and endurance of more than 10,000 cycles, our method provides a powerful means to tune ferrimagnetic spin textures and dynamics, with broad applicability in the rapidly emerging field of ferrimagnetic spintronics.

We present a multiscale theoretical framework to investigate the interplay between diffusion and finite lattice deformation in phase transformation materials. In this framework, we use the Cauchy–Born Rule and the Principle of Virtual Power to derive a thermodynamically consistent theory coupling the diffusion of a guest species (Cahn–Hilliard type) with the finite deformation of host lattices (nonlinear gradient elasticity). We adapt this theory to intercalation materials – specifically Li 1 − 2 Mn 2 O 4 – to investigate the delicate interplay between Li-diffusion and the cubic-to-tetragonal deformation of lattices. Our computations reveal fundamental insights into the microstructural evolution pathways under dynamic discharge conditions, and provide quantitative insights into the nucleation and growth of twinned microstructures during intercalation. Additionally, our results identify regions of stress concentrations (e.g., at phase boundaries, particle surfaces) that arise from lattice misfit and accumulate in the electrode with repeated cycling. These findings suggest a potential mechanism for structural decay in Li 2 Mn 2 O 4. More generally, we establish a theoretical framework that can be used to investigate microstructural evolution pathways, across multiple length scales, in first-order phase transformation materials. [ABSTRACT FROM AUTHOR]

Sodium metal has been widely studied in the field of batteries due to its high theoretical specific capacity (∼1,166 mAh/g), low redox potential (-2.71 V compared to standard hydrogen electrode), and low-cost advantages. However, problems such as unstable solid electrolyte interface (SEI), uncontrolled dendrite growth, and side reactions between solid-liquid interfaces have hindered the practical application of sodium metal anodes (SMAs). Currently, lots of strategies have been developed to achieve stabilized sodium metal anodes. Among these strategies, modified metal current collectors (MCCs) stand out due to their unique role in accommodating volumetric fluctuations with superior structure, lowering the energy barrier for sodium nucleation, and providing guided uniform sodium deposition. In this review, we first introduced three common metal-based current collectors applied to SMAs. Then, we summarized strategies to improve sodium deposition behavior by optimally engineering the surface of MCCs, including surface loading, surface structural design, and surface engineering for functional modification. We have followed the latest research progress and summarized surface optimization cases on different MCCs and their applications in battery systems.

Self-shaping hydrogel actuators have promising applications in various fields. However, one hydrogel actuator can generally access only one specifically predefined deformation and output force, which are determined by its thermodynamic equilibrium swelling state under external stimuli. Here, we present a simple yet versatile strategy for precisely programming the output force/energy of dual-gradient hydrogel actuators. The strategy is based on thermodynamic nonequilibrium snapping deformations occurring during the recovery process of predeformed dual-gradient hydrogel actuators in low-temperature water. The output force/energy of such thermodynamic nonequilibrium snapping deformation is highly associated with predeformation conditions of the hydrogel actuators, which increases with the increase of the predeformation temperature or time. In consequence, just by adjusting the predeformation conditions of the dual-gradient hydrogel actuators, their output force, energy, and power can be modulated precisely and continuously during the snapping deformation. The as-prepared hydrogel actuators can not only be used as smart lifters and grippers with ultrahigh accuracy of weight identification but also act as smart switches in the timing circuits with precisely adjustable operating time, paving the way for the design of a new generation of actuation materials.

Prion diseases are caused by the misfolding of prion protein (PrP). Misfolded PrP forms protease-resistant aggregates in vivo (PrPSc) that are able to template the conversion of the native form of the protein (PrPC), a property shared by in vitro–produced PrP fibrils. Here we produced amyloid fibrils in vitro from recombinant, full-length human PrPC(residues 23–231) and determined their structure using cryo-EM, building a model for the fibril core comprising residues 170−229. The PrP fibril consists of two protofibrils intertwined in a left-handed helix. Lys194 and Glu196 from opposing subunits form salt bridges, creating a hydrophilic cavity at the interface of the two protofibrils. By comparison with the structure of PrPC, we propose that two α-helices in the C-terminal domain of PrPCare converted into β-strands stabilized by a disulfide bond in the PrP fibril. Our data suggest that different PrP mutations may play distinct roles in modulating the conformational conversion.

Cryptochromes (CRYs) are blue-light receptors in plants that harbor FAD as a cofactor and regulate various physiological responses. Photoactivated CRYs undergo oligomerization, which increases the binding affinity to downstream signaling partners. Despite decades of research on the activation of CRYs, little is known about how they are inactivated. Binding of blue-light inhibitors of cryptochromes (BICs) to CRY2 suppresses its photoactivation, but the underlying mechanism remains unknown. Here, we report crystal structures of CRY2N (CRY2 PHR domain) and the BIC2–CRY2N complex with resolutions of 2.7 and 2.5 Å, respectively. In the BIC2–CRY2N complex, BIC2 exhibits an extremely extended structure that sinuously winds around CRY2N. In this way, BIC2 not only restrains the transfer of electrons and protons from CRY2 to FAD during photoreduction but also interacts with the CRY2 oligomer to return it to the monomer form. Uncovering the mechanism of CRY2 inactivation lays a solid foundation for the investigation of cryptochrome protein function.

Use of growth retardants enables post-planting optimization of vegetative growth, which is particularly important given ongoing climate change. Mepiquat chloride is an economical and safe retardant widely applied in cotton farming, but it is not uniformly effective. Here, identification of its molecular target as the ent-copalyl diphosphate synthase that initiates gibberellin biosynthesis enabled the introduction of selective agrochemical inhibition, leaving intact more specialized metabolism important for resistance to biotic and abiotic stresses.

N6-methyladenosine (m6A), a ubiquitous RNA modification, is installed by METTL3-METTL14 complex. The structure of the heterodimeric complex between the methyltransferase domains (MTDs) of METTL3 and METTL14 has been previously determined. However, the MTDs alone possess no enzymatic activity. Here we present the solution structure for the zinc finger domain (ZFD) of METTL3, the inclusion of which fulfills the methyltransferase activity of METTL3-METTL14. We show that the ZFD specifically binds to an RNA containing 5′-GGACU-3′ consensus sequence, but does not to one without. The ZFD thus serves as the target recognition domain, a structural feature previously shown for DNA methyltransferases, and cooperates with the MTDs of METTL3-METTL14 for catalysis. However, the interaction between the ZFD and the specific RNA is extremely weak, with the binding affinity at several hundred micromolar under physiological conditions. The ZFD contains two CCCH-type zinc fingers connected by an anti-parallel β-sheet. Mutational analysis and NMR titrations have mapped the functional interface to a contiguous surface. As a division of labor, the RNA-binding interface comprises basic residues from zinc finger 1 and hydrophobic residues from β-sheet and zinc finger 2. Further we show that the linker between the ZFD and MTD of METTL3 is flexible but partially folded, which may permit the cooperation between the two domains during catalysis. Together, the structural characterization of METTL3 ZFD paves the way to elucidate the atomic details of the entire process of RNA m6A modification.

The spin–orbit torque (SOT) that arises from materials with large spin–orbit coupling promises a path for ultralow power and fast magnetic-based storage and computational devices. We investigated the SOT from magnetron-sputtered BixSe(1–x)thin films in BixSe(1–x)/Co20Fe60B20heterostructures by using d.c. planar Hall and spin-torque ferromagnetic resonance (ST-FMR) methods. Remarkably, the spin torque efficiency (θS) was determined to be as large as 18.62 ± 0.13 and 8.67 ± 1.08 using the d.c. planar Hall and ST-FMR methods, respectively. Moreover, switching of the perpendicular CoFeB multilayers using the SOT from the BixSe(1–x)was observed at room temperature with a low critical magnetization switching current density of 4.3 × 105A cm–2. Quantum transport simulations using a realistic sp3tight-binding model suggests that the high SOT in sputtered BixSe(1–x)is due to the quantum confinement effect with a charge-to-spin conversion efficiency that enhances with reduced size and dimensionality. The demonstrated θS, ease of growth of the films on a silicon substrate and successful growth and switching of perpendicular CoFeB multilayers on BixSe(1–x)films provide an avenue for the use of BixSe(1–x)as a spin density generator in SOT-based memory and logic devices. Sputtered BixSe(1–x)thin films can generate very large current-induced spin–orbit torque, capable to switch both in-plane and out-of-plane magnetized CoFeB-based structures deposited on top, at room temperature.

The plant UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8) exists as a homodimer in its inactive ground state. Upon UV-B exposure, UVR8 monomerizes and interacts with a downstream key regulator, the CONSTITUTIVE PHOTOMORPHOGENIC 1/SUPPRESSOR OF PHYA (COP1/SPA) E3 ubiquitin ligase complex, to initiate UV-B signaling. Two WD40 proteins, REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1 (RUP1) and RUP2 directly interact with monomeric UVR8 and facilitate UVR8 ground state reversion, completing the UVR8 photocycle. Here, we reconstituted the RUP-mediated UVR8 redimerization process in vitroand reported the structure of the RUP2-UVR8W285Acomplex (2.0 Å). RUP2 and UVR8W285Aformed a heterodimer via two distinct interfaces, designated Interface 1 and 2. The previously characterized Interface 1 is found between the RUP2 WD40 domain and the UVR8 C27 subregion. The newly identified Interface 2 is formed through interactions between the RUP2 WD40 domain and the UVR8 core domain. Disruption of Interface 2 impaired UV-B induced photomorphogenic development in Arabidopsis thaliana. Further biochemical analysis indicated that both interfaces are important for RUP2-UVR8 interactions and RUP2-mediated facilitation of UVR8 redimerization. Our findings suggest that the two-interface-interaction mode is adopted by both RUP2 and COP1 when they interact with UVR8, marking a step forward in understanding the molecular basis that underpins the interactions between UVR8 and its photocycle regulators.

Using in situatomic-resolution scanning transmission electron microscopy, atomic movements and rearrangements associated with diffusive solid to solid phase transformations in the Pt–Sn system are captured to reveal details of the underlying atomistic mechanisms that drive these transformations. In the PtSn4to PtSn2phase transformation, a periodic superlattice substructure and a unique intermediate structure precede the nucleation and growth of the PtSn2phase. At the atomic level, all stages of the transformation are templated by the anisotropic crystal structure of the parent PtSn4phase. In the case of the PtSn2to Pt2Sn3transformation, the anisotropy in the structure of product Pt2Sn3dictates the path of transformation. Analysis of atomic configurations at the transformation front elucidates the diffusion pathways and lattice distortions required for these phase transformations. Comparison of multiple Pt–Sn phase transformations reveals the structural parameters governing solid to solid phase transformations in this technologically interesting intermetallic system.

Purpose: This study aimed to develop a moderated mediation model to explain the relationship between perceived organizational justice and the counterproductive work behavior (CWB) of Chinese public servants. In this model, the authors assumed that job burnout mediates the relationship between perceived organizational justice and CWB and that moral identity moderates the relationship between job burnout and CWB. Design/methodology/approach: A total of 210 public servants in China participated in this study, and their characteristics were measured by self-report tools. Hierarchical multiple regression analyses were used to test the moderated mediation model. Findings: Analysis of the data demonstrated that perceived organizational justice, job burnout and moral identity influenced CWB. Moral identity moderated the relationship between job burnout and CWB, such that individuals with low moral identity are more likely to engage in CWB. Moreover, job burnout mediated the effect of perceived organizational justice on CWB, and the mediating effect of job burnout was moderated by moral identity. The indirect effect of perceived organizational justice on CWB through job burnout was significant among individuals with low moral identity but not among individuals with high moral identity. Research limitations/implications: The findings highlight the self-regulatory function of moral identity in preventing CWB. Practical implications: The study offers several significant suggestions to reduce CWB in Chinese public sector administration, such as by improving organizational justice perception, recruiting and selecting individuals with reference to their moral identity and monitoring employees’ job burnout regularly. Originality/value: The authors developed and verified a moderated mediated model on the relationship between perceived organizational justice and CWB. The study revealed that job burnout has a mediating effect on the perceived organizational justice–CWB relation, providing important insights into the processes through which perceived organizational justice affects CWB.

The structure of the METTL3–METTL14 complex, which mediates N6-adenosine methylation of RNA, suggests that the METTL3 subunit is the catalytic core while METTL14 serves to bind RNA.

Interlayer exchange coupling in polycrystalline Co2FeAl/Cr/Co2FeAl multilayers with Ta and MgO capping layers is investigated. Compared with Ta‐capped samples, the MgO capping layer induces the oscillatory coupling periods, ≈2.1 nm for Si substrate and ≈4.0 and ≈1.9 nm for SiO2substrate. The oscillatory coupling period originates from the formation of quantum well states at the Cr/Co2FeAl interface due to the MgO capping layer. Meanwhile, Δ1Bloch state in the majority spin and Δ2'Bloch state in the minority spin contribute to the short (≈2.1 and ≈1.9 nm) and long oscillatory period (≈4.0 nm) in the disordered B2 Co2FeAl multilayers, respectively. The interlayer exchange coupling (IEC) effect in polycrystalline CFA multilayers is investigated. Both substrates and capping layers can modify the IEC of CFA multilayers. The remarkable single‐oscillatory coupling period (≈2.1 nm) on Si substrate and double‐oscillatory coupling period (≈4.0 and ≈1.9 nm) on SiO2substrate are observed.

A rapid and sensitive method was developed for the determination of eight nitrobenzenes and four nitrochlorobenzenes in water. The method is based on dispersive liquid-liquid microextraction (DLLME) followed by gas chromatography-mass spectrometry (GC-MS). The key factors influencing the extraction efficiencies, including the nature and volume of the extraction and dispersion solvent and the ratios of the extraction solvent and dispersion solvent were examined and optimized. Under the optimized conditions, the method yields a linear correlation at a concentration range of 0.5 μg L−1–500.0 μg L−1for all the target analytes with correlation coefficients (R2) of 0.9915 to 1.0000, and relative standard deviations (RSD, n= 6) of between 4.9% and 8.2%, depending on the compound analysed. In addition, good pre-concentration factors of 243 to 525 for each specific compound were achieved. These results suggest that the method presented herein is a rapid and powerful microextraction technique that is useful for the detection of these organic pollutants in water samples and is suitable for emergency monitoring.

A key cause of chemo-mechanical degradation in battery electrodes is that they undergo abrupt phase transformation during the charging/discharging cycle. This phase transformation is accompanied by lattice misfit strains that nucleate microcracks, induce fracture and, in extreme cases, amorphize the intercalation electrode. In this work, we propose a strategy to prevent the chemo-mechanical degradation of intercalation electrodes: we show that by engineering suitable film strains we can regulate the phase transformations in thin-film intercalation electrodes and circumvent the large volume changes. We test this strategy using a combination of theory and experiment: we first analytically derive the effect of film strain on the electrochemical response of a thin-film intercalation electrode and next apply our analytical model to a representative example (Li x V 2 O 5 with multiple phase transformations). We then test our theoretical predictions experimentally. Specifically, we electrochemically cycle thin-film V 2 O 5 electrodes with different film strains and measure their structure, voltage, and stress responses. Our findings show that tensile film strains lower the voltage for phase transformations in thin-film V 2 O 5 electrodes and facilitate their reversible cycling across a wider voltage window without chemo-mechanical degradation. These results suggest that film strain engineering is an alternative approach to preventing chemo-mechanical degradation in intercalation electrodes. Beyond thin-film electrodes, our findings from this study are applicable to the study of stress-induced phase transformations in particle-based electrodes and the thin surface layers forming on cathode particles. • Film strains modify the free energy landscape of phase transformation electrodes. • We engineer film strains to circumvent structural degradation in V 2 O 5 electrodes. • Our work initiates an approach to address chemo-mechanical challenges in electrodes. [ABSTRACT FROM AUTHOR]

Abstract: The current-driven domain wall motion was investigated on permalloy nanowires with different dimensions by micromagnetic simulations. The critical current density increased with the reduction in both the width and thickness of nanowires because of the enhanced hard-axis anisotropy. At a thickness of 5 nm, the critical current density decreased with the reduction of the nanowire width because of the reduced domain wall width.

In October 2004, a swine farm in Jinchang, Gansu Province, China, experienced an outbreak of toxoplasmosis. Most of the affected pigs had a rectal temperature greater than 40°C and gradually lost their appetite. Morbidity reached 57%, and mortality was approximately 2%. Analysis of blood samples from affected pigs using hemagglutination inhibition (HI) assay, immunoglobulin G—enzyme-linked immunosorbent assay (IgG-ELISA), and IgM-ELISA tests showed high titers of anti—Toxoplasma gondiiantibody. Tachyzoites of T. gondiiwere found in body fluids of mice inoculated intraperitoneally with ground samples from the heart, liver, spleen, and brain of 2 sick pigs. In addition, the inoculation of 5 pigs with T. gondiitachyzoites caused death in 2 of the pigs. The origin of this outbreak was concluded to be food-borne T. gondiiinfection.

Nature 534, 575–578 (2016);doi:10.1038/nature18298 In the Acknowledgements section of this Letter, the second Ministry of Science and Technology grant number should have been 2013CB910200 rather than 2013CB900200; this has been corrected online.

We report on perpendicular magnetic anisotropy (PMA) in a Pt/Co2FeAl/MgO sandwiched structure with a thick Co2FeAl layer of 2-2.5 nm. The PMA is thermally stable and the anisotropy energy density Kuis 1.3×106erg/cm3for the structure with 2 nm Co2FeAl after annealing at 350 °C. The annealing temperature and Co2FeAl thickness greatly affect the PMA. Our results provide an effective way to realize relatively thick perpendicularly magnetized Heusler alloy films.