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Spurs have played an important role in the radiation of the genus Aquilegia, but little is known about how the spurless state arose in A. ecalcarata. Here we aim to characterize the genetic divergence within A. ecalcarata and gain insights into the origin of this species. A total of 19 populations from A. ecalcarata and 23 populations from three of its closest relatives (Aquilegia kansuensis, Aquilegia rockii and Aquilegia yabeana) were sampled in this study. We sequenced fifteen nuclear gene fragments across the genome and three chloroplast loci to conduct phylogenetic, PCoA and STRUCTURE analyses. Our analyses indicate that A. ecalcarata may not be monophyletic and can be divided into two distinct lineages (A. ecalcarata I and A. ecalcarata II). A. ecalcarata I is genetically close to A. kansuensis, whereas A. ecalcarata II is close to A. rockii. Isolation-with-migration analysis suggested that historical gene flow was low between A. ecalcarata I and A. rockii, as well as between A. ecalcarata II and A. kansuensis. The two distinct lineages of A. ecalcarata show significant divergence in 13 floral traits and also have distinct distributions. In addition, both A. ecalcarata I and II are adapted to a stony environment that differs from that of their closest relatives, indicating a habitat shift may have driven new adaptations. Our findings enrich the understanding of how floral evolution contributes to species diversification.

Large-scale N-S shortening induced by India-Asia convergence caused the formation of numerous E-W−trending mountain ranges in Tibet. However, the mechanism(s) of formation of N-S−trending mountain ranges remains elusive. We report on a felsic magmatic belt located along the N-S−trending Yardoi-Kongbugang mountain ranges on the flank of the Cona rift in the eastern Tethyan Himalaya. Zircon and monazite geochronology and whole-rock geochemistry revealed three epochs of middle- to lower-crustal anatexis beneath the Cona rift at ca. 47−42 Ma, 35−34 Ma, and 24−14 Ma. The mid-Eocene and early Oligocene granitoids show adakitic signatures indicating continuous crustal thickening, while the formation of Miocene leucogranites and N-S−trending dacitic dikes was related to ductile crustal extension. Silicic melts were exposed along the whole rift since the early Oligocene, suggesting that the early Oligocene could be regarded as a transitional epoch from tectonic compression to orogen-parallel extension. Widespread mid-Eocene and Miocene magmatism in the Himalaya, together with coeval metamorphic anatexis, represents two phases of crustal weakening. The weakened crustal zones under continued India-Asia convergence may have favored uplift and subsequent lateral flow of the weak zones, which initiated E-W extension. Finally, significant upwelling of the weak zones evolved into magma extrusion and formed the N-S−trending mountain ranges. This study provides new insights into the mechanisms of surface uplift and E-W extension and challenges the common view of initiation of E-W extension in southern Tibet not earlier than the early Miocene.

S1: Analytical methods. S2: Detailed descriptions of the results of zircon and monazite age dating. S3: Supplementary Figures. S4: Supplementary Tables. Supplemental Dataset.

Two-dimensional layered materials commonly face hindered electron transfer and poor structure stability, thus limiting their application in high-rate and long-term sodium ion batteries. In the current study, we adopt finite element simulation to guide the rational design of nanostructures. By calculating the von Mises stress distribution of a series of carbon materials, we find that the hollow biconcave structure could effectively alleviate the stress concentration resulting from expansion. Accordingly, we propose a biconcave-alleviated strategy based on the Aspergillus niger-derived carbon (ANDC) to construct ANDC/MoS2 with a hollow biconcave structure. The ANDC/MoS2 is endowed with an excellent long-term cyclability as an anode of sodium ion batteries, delivering a discharge capacity of 496 mAh g-1 after 1000 cycles at 1 A g-1. A capacity retention rate of 94.5% is achieved, an increase of almost seven times compared with the bare MoS2 nanosheets. Even at a high current density of 5 A g-1, a reversible discharge capacity around 400 mAh g-1 is maintained after 300 cycles. ANDC/MoS2 could also be used for efficient lithium storage. By using in situ TEM, we further reveal that the hollow biconcave structure of ANDC/MoS2 has enabled stable and fast sodiation/desodiation.

Objective To explore the effects of miR-494 inhibition through the NF-κB signaling pathway on lipopolysaccharide (LPS)-induced acute kidney injury (AKI) mouse model. Methods The AKI mice induced by LPS were treated with miR-494 antagomir, and the kidney parameters and indicators of oxidative stress were detected. HE and TUNEL staining were performed to observe the kidney histopathology and the apoptosis in renal tubular epithelial cells (RTECs), respectively. The ROS level was measured using dihydroethidium (DHE) staining. In addition, qRT-PCR, western blotting, immunohistochemistry (IHC), and ELISA were also used to detect gene or protein expression. Results LPS-induced AKI mice injected with the miR-494 antagomir showed reduced blood urea nitrogen (BUN) and serum creatinine (Cr) with improved kidney histopathology. The expression levels of p-IKKα/β, p-IκBα and p65 NF-κB in the nucleus were increased in kidney tissues from the LPS-induced AKI mice, and they were decreased by the miR-494 antagomir. Moreover, the results of IHC showed that the miR-494 antagomir downregulated p65 NF-κB in kidney tissues from the LPS-induced AKI mice, accompanied by decreased levels of TNF-α, IL-1β, IL-6, MDA, NO, and ROS but increased levels of SOD and GSH. In addition, the LPS-induced AKI mice had increased apoptosis in RTECs, as well as increased Caspase-3 and Bax and decreased Bcl-2, which were reversed by the miR-494 antagomir. Conclusions The inhibition of miR-494 could reduce inflammatory responses and improve oxidative stress in kidney tissues from LPS-induced AKI mice by blocking the NF-κB pathway accompanying by reduced apoptosis in RTECs.

The hybrid tracked vehicles(HTV) usually adopt series hybrid powertrain with extra steering mechanism, which has relatively low transmission efficiency and reduces the flexibility of structural arrangement. To overcome the disadvantages, a new kind of single-mode powertrain has been proposed. The power-split hybrid powertrain is composed of three planetary gear (PG) sets connected to one engine, left and right track outputs, and three motors. The proposed powertrain can realize steering while going forward by controlling the output torque on each side without extra steering mechanism or steering shaft. Due to the diversity of the connection way between components and planetary gear sets, a rapid configuration design approach is proposed for the design selection of HTV. The automated dynamic modelling method can show the one-to-one correspondence with the selected feasible groups by establishing two characteristic matrices, which is more simple than other researches. The analytically-based method is proposed to classify all possible connection designs into several groups to decrease the searching scope with improved design efficiency. Finally, the optimal control strategy is used to find the design with optimal fuel economy under typical condition of HTV. The case study is implemented by the proposed design approach which demonstrates better design performances compared with the existing series-hybrid HTV.

This study considers the Upper Cretaceous Qingshankou Formation, Yaojia Formation, and the first member of the Nenjiang Formation in the Western Slope of the northern Songliao Basin. Dark mudstone with high abundances of organic matter of Gulong and Qijia sags are considered to be significant source rocks in the study area. To evaluate their development characteristics, differences and effectiveness, geochemical parameters are analyzed. One-dimensional basin modeling and hydrocarbon evolution are also applied to discuss the effectiveness of source rocks. Through the biomarker characteristics, the source–source, oil–oil, and oil–source correlations are assessed and the sources of crude oils in different rock units are determined. Based on the results, Gulong and Qijia source rocks have different organic matter primarily detrived from mixed sources and plankton, respectively. Gulong source rock has higher thermal evolution degree than Qijia source rock. The biomarker parameters of the source rocks are compared with 31 crude oil samples. The studied crude oils can be divided into two groups. The oil–source correlations show that group I oils from Qing II–III, Yao I, and Yao II–III members were probably derived from Gulong source rock and that only group II oils from Nen I member were derived from Qijia source rock.

Partial melts derived from crustal anatexis exhibit large variations in field characteristics, composition, and isotope geochemistry. The relative influence of melting process and magmatic differentiation on such heterogeneity is a subject of ongoing debate. Boron and molybdeum isotopes have the potential to shed light on the genesis of crustal melts, but the behaviors of B and Mo isotopes during crustal anatexis and differentiation are unclear. Here, we present geochemical and isotopic data, including whole-rock Sr–Nd–B–Mo and mineral B–Mo data, for the Conadong leucogranites in the Himalayan Block, to provide new insights into these issues. The studied samples include two-mica granites (biotite + muscovite), muscovite leucogranites (muscovite ± garnet), and biotite-rich granites. The two-mica granites were derived from muscovite dehydration melting of metasedimentary rocks. Their initial Sr and Nd isotopic compositions show positive correlation, implying non-modal partial melting associated with dissolution of accessory phases. The B contents (3.44–21.2 ppm) of the two-mica granites decrease but their δ11B (−15.80‰ to −13.25‰) and δ98Mo (−0.15‰ to 0.34‰) values increase with increasing Sr and Ba contents. This may have been controlled by different phases involved in non-modal melting (i.e., muscovite and feldspar). The muscovite leucogranites display features of residual liquids. Their δ11B (−15.38‰ to −11.90‰) and δ98Mo (−0.15‰ to 0.17‰) values negatively correlate with Sr and Ba contents, which can be ascribed to shallow-crustal crystal–liquid separation and melt–fluid interaction. The biotite-rich granites are least evolved, with large variations in their initial Sr–Nd isotopic compositions. They show relatively heavy whole-rock B isotopic compositions of −11.97‰ to −9.00‰. These may indicate that biotite-rich granites may be contaminated by entrained restitic minerals (e.g., biotite, feldspar and accessory minerals). Overall, this study demonstrates that compositional diversity of anatectic melts is controlled primarily by melting processes in the source and secondarily by emplacement-level crystal–liquid separation. Both non-modal partial melting and crystal–liquid separation could result in B–Mo isotopic fractionation in anatectic melts.

Li metal is a promising anode material for next-generation energy storage systems owing to its high theoretical capacity and low potential. However, uncontrollable Li dendrite growth during Li plating and stripping results in low coulombic efficiencies and severe safety hazards. Herein, succinic anhydride (SA), an inexpensive and simple molecule, is investigated as a deposition-regulating additive. The relationship between the Li electrodeposition overpotential and the solvation structure of Li ions was systematically analyzed. Electrochemical tests and theoretical calculations indicate that strong complexation between Li+ and SA changes the solvation structure of Li+ and increases the energy barrier for Li deposition, resulting in a higher overpotential for Li electrodeposition. This increase in overpotential is conducive to generating more nucleation sites, reducing the Li nucleus size, and forming smooth Li deposits. XPS results also show that the addition of SA facilitates the formation of an improved SEI structure. Therefore, symmetric Li/Li cells with 3.0 wt% SA in the electrolyte exhibit excellent electrochemical performance over 300 cycles at 1.0 mA cm−2 with a capacity of 0.5 mA h cm−2. Enhanced cycling performance is also observed in Li/LiNi0.8Co0.1Mn0.1O2 full cells. Thus, SA can significantly alter the Li plating behavior, affording a promising strategy for suppressing Li dendrite growth in Li-metal-based batteries.

Adakitic rocks are intermediate-acid magmatic rocks characterized by enrichment in light rare-earth elements, depletion in heavy rare-earth elements, positive to negligible Eu and Sr anomalies, and high La/Yb and Sr/Y ratios. Cenozoic adakitic rocks generated by partial melting of subducted oceanic crust (slab) under eclogite-facies conditions (i.e., the original definition of “adakite”) occur mainly in Pacific Rim volcanic arcs (intra-oceanic, continental, and continental-margin island arcs), whereas those generated by partial melting of thickened lower crust occur mainly in Tethyan Tibetan collisional orogens. In volcanic arcs, adakitic melts derived from the melting of subducted oceanic crust metasomatize the mantle wedge to form a unique rock suite comprising adakite-adakite-type high-Mg andesite-Piip-type high-Mg andesite-Nb-rich basalt-boninite. This suite differs from the basalt-andesite-dacite-rhyolite suite formed from mantle wedge metasomatized by fluids derived from subducted oceanic crust. Previously published data indicate that partial melting of mafic rocks can generate adakitic magmas under pressure, temperature, and hydrous conditions of 1.2–3.0 GPa, 800–1000°C, and 1.5–6.0 wt.% H2O, respectively, leaving residual minerals of garnet and rutile with little or no plagioclase. Cenozoic Au and Cu deposits occur proximally to adakitic rocks, with host rocks of some deposits actually being adakitic rocks. Adakitic rocks thus have important implications for both deep-Earth dynamics and Cu-Au mineralization/exploration. Although studies of Cenozoic adakitic rocks have made many important advances, there remain weaknesses in some important areas such as their tectonic settings, petrogenesis, magma sources, melt-mantle interactions of pre-Cenozoic adakitic rocks, and their relationship with the onset of plate tectonics and crustal growth. Future research directions are likely to involve (1) the generation of adakitic magmas by experimental simulations of partial melting of different types of rock (including intermediate-acid rocks) and magma fractional crystallization at different temperatures and pressures, (2) the relationship between magma reservoir evolution and the formation of adakitic rocks, (3) the tectonic setting and petrogenesis of pre-Cenozoic adakitic rocks and related geodynamic processes, (4) interactions between slab melts and the mantle wedge, (5) the formation of Archean adakitic tonalite-trondhjemite-granodiorite and its link to the onset of plate tectonics and crustal growth, and (6) the relationship between the formation of adakitic rocks and metal mineralization in different tectonic settings.

Whether arc magmatism occurs above oceanic subduction zones is the forefront of studies on convergent plate margins. The most important petrologic issue related to the evolution of arc systems is the origin of arc magmatism, among which arc basalts are the most important one because they provide insights into mantle enrichment mechanism and crust-mantle interaction at oceanic subduction zones. Fluids or melts released either by dehydration or by melting of subducting oceanic slab infiltrate and metasomatize the overlying mantle wedge at varying depth, leading to the formation of source regions of arc basalts. Such processes make most of arc basalts commonly enriched in large ion lithosphile elements and light rare earth elements, but depleted in high-field strength elements and heavy rare earth elements. Small amounts of arc basalts are characterized by relatively high Nb contents or by Nb enrichment. Rare basalts with compositions similar to ocean island basalts or mid-ocean ridge basalt also occur in arc systems. For these peculiar rocks, it remains debated whether their source is affected by subduction-related components. During their ascent and before their eruption, arc basaltic magmas are subjected to crystal fractionation, mixing and crustal contamination. In addition to the contribution of subducting slab components to the mantle source of arc basalts, the materials above the subducting slab at forearc depths would have been transported either by drag or by subduction erosion into the subarc mantle and into the source of arc magmas. Heats and materials brought by corner flows also play important roles in the generation of arc basalts. Despite the important progresses made in recent studies of arc basalts, further efforts are needed to investigate subarc mantle metasomatism, material recycling, the formation of arc magma sources, geodynamic mechanism in generating arc basalts, and their implicationd s for the initiation of plate tectonics on Earth.

Copper-containing composites have been widely investigated among various sodium-layered cathode materials due to the low cost and abundance of the copper element. However, the electrochemical performance of these composites is usually deteriorated by the phase transitions corresponding to the stepwise charge/discharge curves, leading to an unsatisfactory capacity stability. Herein, we report that an improved electrochemical performance was achieved by substituting manganese with lithium in the Ni/Co-free P2-type Na0.6Mn0.8−xLixCu0.2O2−δ (x = 0, 0.05, 0.1, 0.15 and 0.2, δ > 0) composites with smooth charged/discharged curves. A capacity retention rate was increased from 54.3% to 82.8% over 200 cycles after adding 0.15 mole of lithium in per stoichiometric composites (Na0.6Mn0.65Li0.15Cu0.2O2−δ). Moreover, the rate performances were all enhanced in the lithium-incorporated composites compared to that of the pristine one. The interphase changes during and after cycling were studied by ex situ and in situ electrochemical impedance spectroscopy measurements, which prove that Li benefits the charge transfer and stabilizes the interphase of the Na0.6Mn0.65Li0.15Cu0.2O2−δ electrode. The in situ X-ray diffractometry results illustrate an alleviated crystallographic change in Na0.6Mn0.65Li0.15Cu0.2O2−δ compared to the Li-free electrode. These combined results provide explanations for the enhanced electrochemical performance after Li substitution in the Na0.6Mn0.8Cu0.2O2 composites from the aspect of the interfacial properties and structure variation. In addition, the online differential electrochemical mass spectrometry test demonstrates that the overall evolved CO2 gas in Na0.6Mn0.65Li0.15Cu0.2O2−δ cell is lower than that in the lithium-free cell during the initial cycle.

Two rare guanidine-type alkaloids, Buthutin A (1) and Buthutin B (2), along with two other compounds (3, 4), were isolated from Buthus martensii Karsch, and determined using extensive spectroscopic data analysis and high resolution-mass spectrometry. Compound 1 showed the most potent inhibition on AChE and BChE with IC50 values of 7.83 ± 0.06 and 47.44 ± 0.95 μM, respectively. Kinetic characterization of compound 1 confirmed a mixed-type of AChE inhibition mechanism in accordance with the docking results, which shows its interaction with both catalytic active (CAS) and peripheral anionic (PAS) sites. The specific binding of compound 1 to PAS domain of AChE was also confirmed experimentally. Moreover, compounds 1 and 3 exhibited satisfactory biometal binding abilities toward Cu2+, Fe2+, Zn2+ and Al3+ ions. These results provide a new evidence for further development and utilization of B. martensii in health and pharmaceutical products.

Thyroid cancer is common in China. Thyroid adenocarcinoma metastases can be local or distal metastasis. Local metastasis presents as a hard and fixed lymph node in the neck, while distant metastases are found in the lung, skull, vertebrae, and pelvis. However, thyroid follicular carcinomas are mostly observed in hematogenous metastases. The thyroid adenocarcinoma and follicular carcinoma of the thyroid gland are often misdiagnosed. Here, we report the case of a 53-year-old female patient. More than 2 years after her initial diagnosis, her left chest wall was physically examined. The results revealed a progressive enlargement that had a hard quality, poor activity, unclear boundary, pressure pain, and percussion pain. Thyroid follicular cell carcinoma was subsequently diagnosed and treated surgically. The thyroid carcinoma had multiple bone metastases, and the thyroid follicular carcinoma had spread to the chest wall through the blood vessels. Thus, preoperative procedures and follow-up should be strengthened because early pathological thyroid follicular carcinoma and thyroid adenoma can easily be misdiagnosed. Pathologic consultation and follow-ups should be strengthened to prevent misdiagnosis.

The International League Against Epilepsy (ILAE) defined drug‐resistant epilepsy (DRE) that epilepsy seizure symptoms cannot be controlled with two well‐tolerated and appropriately chosen antiepileptic drugs, whether they are given as monotherapy or in combination. According to the WHO reports, there is about 30%‐40% of epilepsy patients belong to DRE. These patients need some treatments other than drugs, such as epilepsy surgery, and neuromodulation treatment. Traditional surgical approaches may be limited by the patient's clinical status, pathological tissue location, or overall prognosis. Thus, neuromodulation is an alternative choice to control their symptoms. Vagus nerve stimulation (VNS) is one of the neuromodulation methods clinically, which have been approved by the Food and Drug Administration (FDA). In this review, we systematically describe the clinical application, clinical effects, possible antiepileptic mechanisms, and future research directions of VNS for epilepsy.

As a cost-effective element, Mg has been applied as doped inactive atom to improve the electrochemical performance of sodium-ion cathode materials. Herein, we report Mg-substituted Na0.67Mn0.65Ni0.2Co0.15-xMgxO2 composites as high-performance cathode for sodium-ion batteries and investigate the underlying working mechanism using in situ investigation techniques to monitor the operando changes of electrodes. In situ X-ray diffraction investigation demonstrates P2-type structure is well preserved even charged to 4.3 V and the changes of lattice parameters and unit cell volume of Na0.67Mn0.65Ni0.2Mg0.15O2 are alleviated via Mg replacement. As a result, the capacity retention increases from 62% in Na0.67Mn0.65Ni0.2Co0.15O2 to 94% in Na0.67Mn0.65Ni0.2Mg0.15O2. Meanwhile, less CO2 evolution was detected in the coin cell with Na0.67Mn0.65Ni0.2Mg0.15O2 electrode than in that with Na0.67Mn0.65Ni0.2Co0.15O2 electrode in online differential electrochemical mass spectrometry test, suggesting a depressed side reaction between electrode and electrolyte after Mg completely replacing Co. In situ electrochemical impedance spectroscopy investigation further proves Mg is beneficial for the interfacial conductivity enhancement compared to Co, which provides evidence for enhanced high rate capabilities. These comprehensive results provide new viewpoints to explain the improved cycling and rate capabilities from the aspects of crystal structure evolution, coin cell gas evolution and electrolyte/electrode interface conductivity during charge/discharge process.

Solid-state electrolytes are promising candidates for applications in next-generation lithium-metal batteries (LMBs) because they eliminate the leakage hazards of liquid organic electrolytes and improve the reliability of LMBs in practical applications. However, the inherent defects such as low ionic conductivity and poor interfacial compatibility between the solid electrolyte and electrode hinder their extensive applications. At the same time, the rapid and uneven early nucleation of the lithium metal can lead to large amounts of dendrites in later stages, which gives rise to serious safety problems. Hence, a composite solid-state electrolyte, which consists of PEO, an inorganic ionic conductor, lithium aluminium germanium phosphate (LAGP), and a solid plasticizer, succinonitrile (SN), was explored to improve electrode interphase and ion conductivity. A Li-ion enrichment area could be formed by LAGP, indicating the formation of a fast Li-ion pathway. The crystallinity of PEO decreased effectively upon the introduction of LAGP and SN; thus, the optimized PEO18-LiTFSI-14 wt% LAGP-15 wt% SN electrolyte (SPE-14-15) exhibited excellent ionic conductivity of 1.26 × 10−4 S cm−1 at 30 °C. Meanwhile, SN could improve the interfacial compatibility between the electrode and SPE, therefore inhibiting the growth of lithium dendrites significantly. Li|Li symmetrical cells with the SPE-14-15 electrolyte yielded low hysteresis of 40 mV for 1000 h at 0.2 mA cm−2 and 40 °C. Notably, the Li|SPE|LFP all-solid-state LMB demonstrated outstanding specific capacity of 142.6 mA h g−1 after 200 cycles at 40 °C, and 91.2% of the initial capacity was retained. Moreover, for the first time, various electrochemical techniques combined with SEM analysis were performed to systematically investigate various chemical and kinetic properties of several composite SPEs on the deposition of lithium.

In this work, a bioassay-guided fractionation strategy was used to isolate 26 phenolic compounds from the ethyl acetate partition of an ethanol extract of the aerial parts of Glycyrrhiza uralensis Fisch. ex DC. Among them, 8 prenylated phenolic compounds (glycyuralins Q-X) were described for the first time. The two enantiomers of glycyuralin Q were purified and their absolute configurations were established by ECD spectral calculations. (1″R, 2″S)-glycyuralin Q and (1″S, 2″R)-glycyuralin Q showed significant inhibitory activities against SARS-CoV-2 virus proteases 3CL

Spurs have played an important role in the radiation of the genus

With the development of intelligent transportation system, intelligent network technology has been studied on a large scale in vehicle field. Electrification of vehicles and drive-by-wire chassis provide possibilities for the application of connected autonomous electrified vehicles. Regenerative braking control is an important field among drive-by-wire chassis control technologies. Regenerative braking control is a multi-objective optimization problem, which has the aim of improving regenerative energy efficiency, brake performance, and brake comfort. Therefore, a model predictive control (MPC) is proposed to solve the problem with consideration of different brake styles, such as aggressive, moderate and conservative. Then, the models of the main components associated with the regenerative braking system are designed and built up in a typical deceleration process for simulation and analysis. The simulation results show that the aggressive style mode is the best brake performance, which cause issues on brake comfort as well. The conservative style mode makes full use of motor braking and has advantage of the brake comfort and regenerative energy efficiency. But, it is not good at rapid braking performance of low brake intensity. The moderate style mode is suitable for most drivers, which is balanced of the above characteristics. Finally, experimental tests under ECE driving cycle are also carried out to further verify the characteristics of proposed three brake modes.

Sheet-like MoSe2/C nanocomposites were synthesized and employed as the cathode of a rechargeable Mg2+/Li+ hybrid battery for the first time, which exhibited an excellent electrochemical performance. The structure transformation of the MoSe2/C nanocomposite materials during the charge-discharge processes was identified by in situ XRD, and the electrochemical reactions taking place in the battery were evidenced. Keywords: In situ XRD, Sheet-like MoSe2/C nanocomposites, Mg2+/Li+ hybrid battery

This study was to investigate the changes of autonomic nerve function and hemodynamics in patients with vasovagal syncope (VVS) during head-up tilt-table testing (HUT). HUT was performed in 68 patients with unexplained syncope and 18 healthy subjects served as control group. According to whether bradycardia, hypotension or both took place during the onset of syncope, the patients were divided during the test into three subgroups: vasodepressor syncope (VD), cardioinhibitory syncope (CI) and mixed syncope (MX) subgroups. Heart rate, blood pressure, heart rate variability (HRV), and deceleration capacity (DC) were continuously analyzed during HUT. For all the subjects with positive responses, the normalized low frequency (LFn) and the LF/HF ratio markedly decreased whereas normalized high frequency (HFn) increased when syncope occurred. Syncopal period also caused more significant increase in the power of the DC in positive groups. These changes were more exaggerated compared to controls. All the patients were indicative of a sympathetic surge in the presence of withdrawal vagal activity before syncope and a sympathetic inhibition with a vagal predominance at the syncopal stage by the frequency-domain analysis of HRV. With the measurements of DC, a decreased vagal tone before syncope stage and a vagal activation at the syncopal stage were observed. The vagal tone was higher in subjects showing cardioinhibitory responses at the syncopal stage. DC may provide an alternative method to understand the autonomic profile of VVS patients.

Doped nanocarbon materials (e.g., carbon nanotubes, graphene) are considered as effective electrocatalyst supports for fuel cells, and their electrochemical properties are closely related to the synthetic methods and the types of doping elements. In the current paper, we report a novel approach to synthesize sulfur-doped multi-walled carbon nanotubes (S-MWCNTs) as a highly efficient support material for Pt nanoparticle catalysts. The S-MWCNTs are obtained by annealing poly(3,4-ethylenedioxythiophene) (PEDOT) functionalized multi-walled carbon nanotubes at 800 °C. The prepared nanohybrids were physically characterized by Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). It has been found that the doping of sulfur into MWCNTs could significantly improve the dispersion of supported Pt nanoparticles of 2.37 nm in size and increase the electrochemically active surface area (ECSA, 161.4 m2 g−1). The doped sulfur atoms not only provide uniformly dispersed anchoring sites for the deposition of Pt nanoparticles on the surface of MWCNTs but also enhance the electron transfer interaction between Pt nanoparticles and the S-MWCNT support. The electrochemical properties of the catalysts were evaluated by using cyclic voltammetry (CV) and chronoamperometry (CA) techniques. The results demonstrate that the as-prepared Pt/S-MWCNTs exhibit much higher electrocatalytic activity, long-term durability and CO-tolerance ability for the methanol oxidation reaction (MOR) compared to the undoped MWCNT supported Pt and commercial Pt/C catalysts.

In the natural state, the soil temperature changes periodically throughout the day, but there is no unified opinion on whether the daily variation of soil temperature affects the mineralization of soil organic carbon. Therefore, the effect of cyclical temperature fluctuations on organic carbon mineralization of purple soil, widely distributed in southwest China, was studied by an incubation experiment in the laboratory. These soils were incubated at three constant temperatures (15, 20, and 25℃) with cyclically fluctuating temperatures (the range was within 15/25℃) and two moisture levels (70% water holding capacity (WHC) and submerged condition). In the entire incubation period (66 d), aerobic and submerged condition, variable temperature (15/25℃) cultivation of purple soil, SOC cumulative mineralization and the mineralization intensity had no obvious differences with constant temperature of 20℃. This indicated that the periodic variable temperature treatment (15/25℃) of SOC mineralization of purple soil with the same accumulated temperature of constant temperature processing (20℃). In addition, except for constant temperature of 15℃, the temperature processing of submerged condition of purple soil SOC cumulative mineralization was significantly higher than 70% WHC treatment (

Crustal reworking in the collisional zones is commonly considered as an important process to result in continental crust differentiation and maturation. However, the reworking mechanism remains unclear. Here, a combined study of zircon SIMS U–Pb age, whole-rock major and trace element, Sr–Nd–Hf and zircon Hf–O isotopic geochemistry was carried out for the Duoma–Namuqie (DM–NMQ) granite porphyry intrusions, including DM, NMQ I, II and III intrusions, in southern Qiangtang, central Tibet. Zircon SIMS U–Pb dating yielded ages of 79–76 Ma, suggesting that they were formed in the later stage of Late Cretaceous. The DM granite porphyries are metaluminous to peraluminous with slightly low SiO2 (69.2–71.4 wt%) and high MgO (0.67–0.79 wt%) contents. They are depleted in high-field-strength elements (HFSEs) and enriched in light rare earth elements (LREEs), large ion lithophile elements (LILEs), and show weakly negative Eu anomalies. The NMQ III granite porphyries show similar elemental features to the DM granite porphyries, but have relatively high SiO2 (69.8–72.2 wt%) and low MgO (0.25–0.28 wt%) contents. Both of them belong to I-type granites. The NMQ I and II granite porphyries are relatively differentiated with high SiO2 (76.4–77.9 wt%), low MgO (0.11–0.16 wt%) contents, and significantly negative Eu anomalies. Extremely low LREE contents and notable REE tetrad effect can be observed in the NMQ II granite porphyries. The NMQ I and II intrusions are fractionated I-type granites. The whole-rock Sr–Nd–Hf and zircon Hf–O isotope data exhibit an enriched trend from the DM granite porphyries ((87Sr/86Sr)i = 0.7049–0.7050, eNd(t) = 1.2–1.6, eHf(t)whole-rock = 9.9–12.0, eHf(t)zircon = 7.4–11.5, δ18O = 6.2–7.1‰) to the NMQ III granite porphyry ((87Sr/86Sr)i = 0.7058–0.7067, eNd(t) = −0.9 to −1.1, eHf(t)whole-rock = 7.0–7.4, eHf(t)zircon = 2.7–9.5, δ18O = 7.2–7.6‰) to the NMQ I and II granite porphyries (eNd(t) = −3.0 to −4.3, eHf(t)whole-rock = 5.3–6.6, eHf(t)zircon = 1.5–7.4, δ18O = 6.6–9.2‰). We suggest that the DM–NMQ granite porphyries were mainly derived by partial melting of the juvenile mafic lower crust with variable volumes of ancient crustal components involved in their magma sources. The way in which these granite porphyries were formed provides evidence for the crustal differentiation and maturation in a post-collisional extensional setting triggered by the far-field rollback of the subducted Neo-Tethys oceanic slab

Antimony has attracted a substantial amount of attention and has been proven to be the most promising anode material for sodium-ion batteries (SIBs) due to its suitable sodium insertion plateaus and high theoretical storage capacity. However, the dramatic volume expansion (up to 390%) during sodiation/desodiation results in severe structural deterioration and rapid capacity decay. As a consequence, antimony anodes exhibit poor cycling stability. Herein, we report a binder-free Sb/NiSb alloy prepared by a controllable electrodeposition process. The inactive nickel provided both good conductivity and structural reinforcement to reduce the large volume expansion/contraction, which endowed the Sb/NiSb anode with excellent cycle stability (521 mAh∙g−1 upon 100 cycles) and rate performance (above 400 mAh∙g−1 at 2000 mA∙g−1) that were superior to those of the bare Sb anode. The excellent Na storage performance of the Sb/NiSb anode was attributed to the synergistic effect of its cauliflower-like structure and the alloying effect of the Sb/NiSb. The operando XRD results indicated that the reaction mechanism resembled that of analogous transition metal antimonides. In addition, a stable solid electrolyte interface (SEI) was observed with operando XRD and HR-TEM of the Sb/NiSb anode. The cost-effective preparation of Sb/NiSb composite anodes and their excellent electrochemical properties offer the potential to prepare a broad spectrum of binder-free metallic alloys (e.g., Bi and Sn) as high-performance anode materials for SIBs.

Granitic pegmatites are considered significant host rocks for the rare metal deposits. However, the enrichment mechanisms for the rare metal elements (e.g., Li, Be, Nb and Ta) remain debated. Here we report the whole-rock and mineral (e.g., muscovite and spodumene) major, trace elements and Li isotopic compositions of the Bailongshan granitic pegmatites in the West Kunlun, NW Tibet, to address this issue. The Bailongshan pegmatites (hosting a super-large Li–Rb polymetallic deposit) are composed of Li-poor and Li-rich pegmatites. The Li-poor pegmatites display high δ7Li values in the whole rock (2.30–4.94‰) and muscovite (2.22–7.55‰). In contrast, the Li-rich pegmatites show low δ7Li values in the whole rock (−1.89 to 0.35‰), muscovite (−3.39 to 4.49‰) and spodumene (−2.83 to 1.87‰). These results, together with the variations of the elements, suggest that the Li-poor and Li-rich pegmatites were produced by the melt-fluid separation during the late stage of granitic magma evolution. This means that the Li-poor pegmatites were formed in a H2O-poor silicate-rich melt system, while the Li-rich pegmatites were generated in a H2O-rich silicate-poor melt (supercritical fluid) system. The melt-fluid separation can lead to significant Li isotope fractionation, with 7Li enriched in the strongly-bonded residual silicate melt, and 6Li preferring to weaker hydrated bonds in the fluid. Alternatively, the Li-rich pegmatites enriched in 6Li could have been induced by preferential accumulation of the faster-diffusing 6Li in the supercritical or near critical fluid. The Li-rich pegmatites experienced extensive crystal-fluid interaction in a relatively closed magmatic-hydrothermal system, which resulted in the leaching and reprecipitation of ore-forming elements, but produced restricted Li isotope fractionation. The exsolved supercritical fluid is more enriched in alkali-, fluxing components (Li, Rb, Cs, P and F) by the continuous interaction with the residual silicate melt. Therefore, the supercritical fluid exsolution plays an important role in the Li isotope fractionation and rare metal mineralization.