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Magnesium (Mg) metal is a promising anode candidate for high-energy and cost-effective multivalent metal batteries, but suffers from severe surface passivation in conventional electrolytes, especially aqueous solutions. Here, we uncover that MgH2, in addition to the well-known MgO and Mg(OH)2, can be formed during the passivation of Mg by water. The formation mechanism and spatial distribution of MgH2, and its detrimental effect on interfacial dynamics and stability of Mg anode are revealed by comprehensive experimental and theoretical investigations. Furthermore, a graphite-based hydrophobic and Mg2+-permeable water-tolerant interphase is drawn using a pencil on the surface of Mg anodes, allowing them to cycle stably in symmetric (> 900 h) and full cells (> 500 cycles) even after contact with water. The mechanistic understanding of MgH2-involved Mg passivation and the design of pencil-drawn waterproof Mg anodes may inspire the further development of Mg metal batteries with high water resistance. This paper uncovers the formation of MgH2, in addition to the well-known MgO and Mg(OH)2, during the passivation of Mg by water, and demonstrates a waterproof Mg metal anode by simply pencil drawing. [ABSTRACT FROM AUTHOR]

Employing quasi-solid-state gel polymer electrolyte (GPE) instead of the liquid counterpart has been regarded as a promising strategy for improving the electrochemical performance of Li metal batteries. However, the poor and uneven interfacial contact between Li metal anode and GPE could cause large interfacial resistance and electrochemical Li stripping/plating inhomogeneity, deteriorating the electrochemical performance. Herein, we proposed that the functional component of composite anode could work as the catalyst to promote the in situ polymerization reaction, and we experimentally realized the integration of polymerized-dioxolane electrolyte and Li/Li22Sn5/LiF composite electrode with low interfacial resistance and good stability by in situ catalyzation polymerization. Thus, the reaction kinetics and stability of metallic Li anode were significantly enhanced. As a demonstration, symmetric cell using such a GPE-Li/Li22Sn5/LiF integration achieved stable cycling beyond 250 cycles with small potential hysteresis of 25 mV at 1 mA·cm−2 and 1 mAh·cm−2, far outperforming the counterpart regular GPE on pure Li. Paired with LiNi0.5Co0.3Mn0.2O2, the full cell with the GPE-Li/Li22Sn5/LiF integration maintained 85.7% of the original capacity after 100 cycles at 0.5 C (1 C = 200 mA·g−1). Our research provides a promising strategy for reducing the resistance between GPE and Li metal anode, and realizes Li metal batteries with enhance electrochemical performance. [ABSTRACT FROM AUTHOR]

Achievement of lithium (Li) metal anode with thin thickness (e.g., ≤ 30 µm) is highly desirable for rechargeable high energy density batteries. However, the fabrication and application of such thin Li metal foil electrode remain challenging due to the poor mechanical processibility and inferior electrochemical performance of metallic Li. Here, mechanico-chemical synthesis of robust ultrathin Li/Li3P (LLP) composite foils (∼ 15 µm) is demonstrated by employing repeated mechanical rolling/stacking operations using red P and metallic Li as raw materials. The in-situ formed Li+-conductive Li3P nanoparticles in metallic Li matrix and their tight bonding strengthen the mechanical durability and enable the successful fabrication of free-standing ultrathin Li metal composite foil. Besides, it also reduces the electrochemical Li nucleation barrier and homogenizes Li plating/stripping behavior. When matching to high-voltage LiCoO2, the full cell with a low negative/positive (N/P) capacity ratio of ∼ 1.5 offers a high energy density of ∼ 522 W·h·kg−1 at 0.5 C based on the mass of cathode and anode. Taking into account its facile manufacturing, potentially low cost, and good electrochemical performance, we believe that such an ultrathin composite Li metal foil design with nanoparticle-dispersion-strengthened mechanism may boost the development of high energy density Li metal batteries. [ABSTRACT FROM AUTHOR]

The pursuit of high energy density Li‐based rechargeable batteries has intrigued numerous research interest on Li metal anode. However, several significant challenges, including severe parasitic reactions and growth of Li dendrites, lead to fast electrode failure and impede its practical implantation. Herein, it is revealed that the dynamic concentration of alloying element in Li solid solution can significantly improve the cycling stability. It is demonstrated that the alloying element of Li solid solution continuously evolved in the reaction layer on cycling. Alloying element got enriched on anode surface after Li stripping, and re‐dispersed into the deposited Li during Li plating processes. The alloying element‐rich surface can reduce the Li nucleation barrier and promote the uniform Li plating behavior. Ultrathin Li solid solution foils are fabricated, and the dynamic alloying element concentration mechanism is further verified, and the cycling lifespan of pure Li is doubled. Consequently, a 1.4 Ah laminated pouch cell with ultrathin Li solid solution anode (30 µm) exhibits high energy density of 836 Wh L−1 and stable cycling performance under the harsh conditions with low negative/positive capacity (N/P) ratio of 2 and electrolyte/capacity (E/C) ratio of 2.6 g Ah−1. [ABSTRACT FROM AUTHOR]

The emergence of caste-differentiated colonies, which have been defined as 'superorganisms', in ants, bees, and wasps represents a major transition in evolution. Lifetime mating commitment by queens, pre-imaginal caste determination and lifetime unmatedness of workers are key features of these animal societies. Workers in superorganismal species like honey bees and many ants have consequently lost, or retain only vestigial spermathecal structures. However, bumble bee workers retain complete spermathecae despite 25-40 million years since their origin of superorganismality, which remains an evolutionary mystery. Here, we show (i) that bumble bee workers retain queen-like reproductive traits, being able to mate and produce colonies, underlain by queen-like gene expression, (ii) the social conditions required for worker mating, and (iii) that these abilities may be selected for by early queen-loss in these annual species. These results challenge the idea of lifetime worker unmatedness in superorganisms, and provide an exciting new tool for the conservation of endangered bumble bee species. Workers in social insects such as honey bees, bumble bees, and ants are expected to spend their lives helping their mother reproduce. Here the authors show that workers of several bumble bee species can in fact mate and lead colonies of their own. [ABSTRACT FROM AUTHOR]

Rechargeable magnesium batteries (RMBs) are promising next‐generation low‐cost and high‐energy devices. Among all RMBs, anode‐free magnesium metal batteries that use in situ magnesium‐plated current collectors as negative electrodes can afford optimal energy densities. However, anode‐free magnesium metal batteries have remained elusive so far, as their practical application is plagued by low Mg plating/stripping efficiency due to nonuniform Mg deposition on conventional anode current collectors. Herein, for the first time, an anode‐free Mg‐metal battery is developed by employing a 3D MXene (Ti3C2Tx) film with horizontal Mg electrodeposition. The magnesiophilic oxygen and reactive fluorine terminations in MXene enable an enriched local magnesium‐ion concentration and a durable magnesium fluoride‐rich solid electrolyte interphase on the Ti3C2Tx film surface. Meanwhile, Ti3C2Tx MXene exhibits a high lattice geometrical fit with Mg (≈96%) to guide the horizontal electrodeposition of Mg. Consequently, the developed Ti3C2Tx film achieves reversible Mg plating/stripping with high Coulombic efficiencies (>99.4%) at high‐current‐density (5.0 mA cm−2) and high‐Mg‐utilization (50%) conditions. When this Ti3C2Tx film is coupled with a pre‐magnesized Mo6S8 cathode, the anode‐free Mg‐metal full‐cell prototype exhibits a volumetric energy density five times higher than its standard Mg‐metal counterpart. This work provides insights into the rational design of anode current collectors to guide horizontal Mg electrodeposition for anode‐free Mg metal batteries. [ABSTRACT FROM AUTHOR]

Magnesium metal batteries are promising candidates for next‐generation high‐energy‐density and low‐cost energy storage systems. Their application, however, is precluded by infinite relative volume changes and inevitable side reactions of Mg metal anodes. These issues become more pronounced at large areal capacities that are required for practical batteries. Herein, for the first time, double‐transition‐metal MXene films are developed to promote deeply rechargeable magnesium metal batteries using Mo2Ti2C3 as a representative example. The freestanding Mo2Ti2C3 films, which are prepared using a simple vacuum filtration method, possess good electronic conductivity, unique surface chemistry, and high mechanical modulus. These superior electro‐chemo‐mechanical merits of Mo2Ti2C3 films help to accelerate electrons/ions transfer, suppress electrolyte decomposition and dead Mg formation, as well as maintain electrode structural integrity during long‐term and large‐capacity operation. As a result, the as‐developed Mo2Ti2C3 films exhibit reversible Mg plating/stripping with high Coulombic efficiency of 99.3% at a record‐high capacity of 15 mAh cm−2. This work not only sheds innovative insights into current collector design for deeply cyclable Mg metal anodes, but also paves the way for the application of double‐transition‐metal MXene materials in other alkali and alkaline earth metal batteries. [ABSTRACT FROM AUTHOR]

Red mud is a strong alkaline waste from the Bayer process for Al production, which is known as a promising polymetallic secondary resource. The stockpiling and landfill disposal of red mud have produced environmental pollution and resource waste. A novel, promising, environmentally friendly technology for simultaneous extraction of valuable metals from red mud was proposed by ammonium sulfate calcination at temperatures of 250–400°C and water leaching. The phase change in the calcination process and various parameters such as the amount of ammonium sulfate, calcination temperature, calcination time, leaching temperature, leaching time and solid-to-liquid ratio on element extraction were investigated. The results indicated that Fe, Cr, Sc and most Al in the red mud were first transformed into (NH4)3(Fe, Cr, Sc, Al)(SO4)3 during the sulfation calcination process and then into NH4(Fe, Cr, Sc, Al)(SO4)2 at 400°C, while the Al in diaspore was not. More than 98.23% Fe, 70.32% Al, 95.38% Sc and 88.07% Cr were extracted under the optimal conditions, while Ti mainly remained in the leaching residue. [ABSTRACT FROM AUTHOR]

The uneven electrochemical reactions of lithium (Li) metal anode is one of the main reasons that hinder its application in rechargeable high energy density batteries. Great progress has been achieved in homogenizing electrochemical reactions of Li metal anode in lab‐scale coin cells, however, it cannot be directly applied to pouch cells, where undesirable defects or side reactions are significantly aggravated. With carbonate electrolyte, multi‐layered negative and positive electrodes (8 × 11 cm), 1.2 Ah sulfurized polyacrylonitrile (SPAN)||Li pouch cell lost all its capacity after 40 cycles under a current of 600 mA, although its counterpart with coin cell configuration showed much higher capacity retention of 94% under the same test condition. Severe corrosion with uneven, porous, dendritic Li deposits is observed for pristine Li electrode in a pouch cell, especially in the near‐tap and the central regions with close connection with the current collector due to the locally amplified current densities. In contrast, Li/Li–Sn alloy composite electrode displays uniform and dense Li plating behavior over the entire test area with significantly suppressed parasitic reactions and gas evolution. As such, a 1.2 Ah SPAN||Li/Li–Sn cell displays much higher capacity retention than SPAN||Li cell (87% for 100 cycles vs. 0 for 40 cycles). [ABSTRACT FROM AUTHOR]

Magnesium metal anodes have attracted widespread attention for their high volumetric capacity and natural abundance, but are precluded from practical applications by poor rate capability and limited lifespan due to sluggish ion‐transfer kinetics and uneven deposition behavior. Herein, for the first time a grain‐boundary‐rich triphasic artificial hybrid interphase, consisting of Sb metal, Mg3Sb2 alloy, and MgCl2, is designed on Mg anode surface by a facile solution treatment method, enabling high‐rate and long‐cycle Mg plating/stripping behavior. The triphasic artificial hybrid interphase affords high magnesiophilicity and ionic conductivity to reduce the energy barriers for Mg2+ desolvation and deposition. Meanwhile, the abundant grain boundaries redistribute Mg2+ flux at the electrode‐electrolyte interface and guide uniform Mg deposition. Accordingly, the as‐designed Mg metal anode achieves ultralong cycling life of 350 h at a high current density of 5 mA cm−2 and a large areal capacity of 5 mAh cm−2, outperforming previously reported Mg metal anodes with artificial interphases. Full cells with Mo6 cathode also show extraordinary stability over a long lifespan of 8000 cycles at a high rate of 5 C. The rational artificial interphase design and the understanding of composition‐structure‐function relationships shed deep insights into the development of fast‐charging and long‐cycling Mg metal batteries. [ABSTRACT FROM AUTHOR]

In cellular-connected unmanned aerial vehicle (UAV) network, a minimization problem on the weighted sum of time cost and expected outage duration is considered. Taking advantage of UAV’s adjustable mobility, a UAV navigation approach is formulated to achieve the aforementioned optimization goal. Conventional offline optimization techniques suffer from inefficiency in accomplishing the formulated UAV navigation task due to the practical consideration of local building distribution and directional antenna radiation pattern. Alternatively, after mapping the navigation task into a Markov decision process (MDP), a deep reinforcement learning (DRL)-aided solution is proposed to help the UAV find the optimal flying direction within each time slot, and thus the designed trajectory towards the destination can be generated. To help the DRL agent commit a better trade-off between sampling priority and diversity, a novel quantum-inspired experience replay (QiER) framework is proposed, via relating experienced transition’s importance to its associated quantum bit (qubit) and applying Grover iteration based amplitude amplification technique. Compared to several representative DRL-related and non-learning baselines, the effectiveness and supremacy of the proposed DRL-QiER solution are demonstrated and validated in numerical results. [ABSTRACT FROM AUTHOR]

A Li/KNO3 composite (LKNO), with KNO3 uniformly implanted in bulk metallic Li, is fabricated for battery anode via a facile mechanical kneading approach, which exhibits high Coulombic efficiency and prolonged cycle life. The mechanism behind the enhanced electrochemical performance of the "salt‐in‐metal" composite is investigated, where KNO3 in metallic Li composite electrode would be sustainably released into the electrolyte. The presence of NO3– stabilizes the solid electrolyte interphase by producing functional Li3N, LiNxOy, and Li2O species. K+ from KNO3 also helps to form an electrostatic shield after its adsorption on the electrode protrusions, which suppresses the dendritic growth of metallic Li. With the above advantages, uniform Li plating with dense and planar structure is realized for the LKNO electrode. These findings reveal a deep understanding of the effect of the "salt‐in‐metal" anode and provide new insights into the use of nitrate additives for high‐energy‐density Li metal batteries. [ABSTRACT FROM AUTHOR]

Metallic lithium (Li) is the ultimate anode candidate for high‐energy‐density rechargeable batteries. However, its practical application is hindered by serious problems, including uncontrolled dendritic Li growth and undesired side reactions. In this study a concept of "salt‐in‐metal" is proposed, and a Li/LiNO3 composite foil is constructed such that a classic electrolyte additive, LiNO3, is embedded successfully into the bulk structure of metallic Li by a facile mechanical kneading approach. The LiNO3 reacts with metallic Li to generate Li+ conductive species (e.g., Li3N and LiNxOy) over the entire electrode. These derivatives afford a stable solid electrolyte interphase (SEI) and effectively regulate the uniformity of the nucleation/growth of Li on initial plating, featuring a low nucleation energy barrier and large crystalline size without mossy morphology. Importantly, these derivatives combined with LiNO3 can in‐situ repair the damaged SEI from the large volume change during Li plating/stripping, enabling a stable electrode‐electrolyte interface and suppressing side reactions between metallic Li and electrolyte. Stable cycling with a high capacity retention of 93.1% after 100 cycles is obtained for full cells consisting of high‐loading LiCoO2 cathode (≈20 mg cm−2) and composite metallic Li anode with 25 wt% LiNO3 under a lean electrolyte condition (≈12 µL) at 0.5 C. [ABSTRACT FROM AUTHOR]

We propose a cascaded neural network (NN) to simultaneously identify the modulation formats and monitor the optical-signal-to-noise ratio (OSNR). In the second-level network, it is a single deep NN (DNN) rather than multiple sub-networks, which makes the architecture more compact and can save the resource for real implementation. However, since the data set is constituted from all modulation formats, the universality can be guaranteed but not for the accuracy and the complexity. To accelerate the estimation process and improve the accuracy, we introduce the transfer learning (TL) and reconstruct the data set with a part from all of the modulation formats for universality and another part from a specific modulation format for TL to pursue higher accuracy. In the experiment, we compare the proposed cascaded single neural network (CSNN) with or without TL, cascaded multiple neural networks (CMNN) and adaptive multi-task learning (MTL) for MFI and OSNR monitoring. In the first-level NN, all of the three schemes can achieve the accuracy of MFI as 100%. In the second-level NN, the CSNN with TL (TL-CSNN) can significantly improve the training speed and decline the RMSE of 0.19 dB compared with CSNN without TL. The TL-CSNN also has faster convergence speed and is more stable compared with CMNN and adaptive MTL. [ABSTRACT FROM AUTHOR]

To enhance transmission performance, privacy level, and energy manipulating efficiency of wireless networks, this article initiates a novel simultaneous wireless information and power transfer (SWIPT) full-duplex (FD) relaying protocol, named harvest-and-opportunistically-relay (HOR). Due to the FD characteristics, the dynamic fluctuation of relay’s residual energy is difficult to quantify and track. To solve this problem, the Markov Chain (MC) theory is invoked. Furthermore, to improve the privacy level of the proposed HOR relaying system, covert transmission performance analysis is performed, where closed-form expressions of the optimal detection threshold and minimum detection error probability are derived. Last but not least, with the aid of stationary distribution of the MC, closed-form expression of transmission outage probability is calculated, based on which transmission outage performance is analyzed. Numerical results have validated the correctness of analyses on transmission outage and covertness. The impacts of key system parameters on the performance of transmission outage and covertness are given and discussed. Based on mathematical analysis and numerical results, we showcase that the proposed HOR model can not only reliably enhance the transmission performance via smartly managing residual energy but also efficiently improve the privacy level of the legitimate transmission party via dynamically adjusting the optimal detection threshold. [ABSTRACT FROM AUTHOR]

Doxorubicin (Dox) is widely used in cancer therapy, but the clinical application is limited by its cardiotoxicity. The underlying mechanism of Dox-induced cardiotoxicity remains unclear. Present study aimed to evaluate the role of NLRP3 inflammasome in Dox-induced cardiotoxicity. The NLRP3 inflammasome was activated in the myocardium of Dox-treating (5 mg/kg, once every other day, cumulative dosage to 15 mg/kg and sacrificed after 2 days of last Dox injection) C57BL/6 mice as shown by the up-regulation of NLRP3 and Caspase-1 p20. Dox (1 μM for 48 h) induced the apoptosis of H9c2 cells and primary cardiomyocytes concomitantly with up-regulation of NLRP3, ASC and Caspase-1 p20 expressions, as well as the increased IL-1β secretion, suggesting the activation of NLRP3 inflammasome. These effects of Dox on H9c2 cells and primary cardiomyocytes can be reversed by MCC950, a specific inhibitor of NLRP3. In view of the key role of ROS on the Dox-induced cardiotoxicity, the relationship between ROS and NLRP3 was further investigated. The ROS level was increased in myocardium, H9c2 cells and primary cardiomyocytes after treating with Dox. Decreasing ROS level by NAC can inhibit the NLRP3 inflammasome activation, secretion of IL-1β and apoptosis in Dox-treating H9c2 cells and primary cardiomyocytes. Collectively, this study reveals a crucial role of ROS/NLRP3-associated inflammasome activation in Dox-induced cardiotoxicity, and NLRP3 inflammasome may represent a new therapeutic target for Dox-induced cardiotoxicity. [ABSTRACT FROM AUTHOR]

Aims Aberrant activation of cardiac fibroblasts leads to cardiac fibrosis, and evolving evidences suggest that endogenous bioactive substances derived from cardiac fibroblasts regulate cardiac fibroblasts activation in an autocrine/paracrine manner. Here we first presented evidence that cardiac fibroblasts can synthesize and secrete calcitonin gene-related peptide (CGRP), therefore, this study aimed to investigate the role of cardiac fibroblasts-derived CGRP in cardiac fibroblasts activation and its regulative mechanism. Methods and results The abundantly expression of CGRP in rat, mouse, and human myocardium allowed us to explore the cellular origin of CGRP, and found that the cardiac CGRP was mainly derived from cardiac fibroblasts. Activating TRPA1 with a specific agonist allyl isothiocyanate promoted the synthesis and secretion of CGRP, as well as intracellular Ca2+. These effects were reversed by TRPA1-specific antagonist HC030031 and Ca2+ chelator BAPTA-AM. TGF-β1 was applied to induce the activation of cardiac fibroblasts, and found that TGF-β1 can increase the mRNA expression and secretion levels of CGRP in cardiac fibroblasts. Either CGRP8–37 (CGRP receptor antagonist) or α-CGRP small interfering RNA (siRNA) aggravated TGF-β1-induced proliferation, differentiation, collagen production, and instigated inflammation in cardiac fibroblasts. Moreover, TGF-β1-induced NF-κB activation including IκBα phosphorylation and p65 nuclear translocation were also promoted by CGRP8–37 and α-CGRP siRNA. NF-κB inhibitor pyrrolidinedithiocarbamate ammonium (PDTC) reversed the effects of CGRP8–37 on NF-κB activation. The promotive effects of CGRP8–37 on TGF-β1-induced activation of cardiac fibroblasts were all reversed by PDTC. Monocrotaline (MCT) induces pulmonary arterial hypertension, progressively leading to right ventricular fibrosis. This model of cardiac fibrosis was developed here to test the potentially beneficial effects of TRPA1 activation in vivo. The non-toxic TRPA1 agonist Cinnamaldehyde (CA) inhibited MCT-induced elevation in right ventricle systolic pressure, RV/LV + S, and right ventricular collagen accumulation, as well as down-regulation of CGRP. CA increased the synthesis and secretion of CGRP, and inhibited TGF-β1-induced activation in cardiac fibroblasts. Conclusion Our data suggested an autocrine role for cardiac fibroblasts-derived CGRP in suppressing activation of cardiac fibroblasts through inhibiting NF-κB activation. Increasing autocrine CGRP by activating TRPA1 can ameliorate cardiac fibrosis. These findings support the notion that CGRP derived from cardiac fibroblasts is an endogenous suppressor of cardiac fibrosis. [ABSTRACT FROM AUTHOR]

The traditional Chinese herb Wu‑Chu‑Yu has been used to treat hypertension for hundreds of years. A previous study indicated that rutaecarpine was the effective component of Wu‑Chu‑Yu, which lowered blood pressure by elevating the expression level of calcitonin gene‑related peptide (CGRP). The present study was performed to investigate the role of transient receptor potential cation channel subfamily V member 1 (TRPV1) in CGRP expression and release induced by rutaecarpine. Dorsal root ganglia (DRG) obtained from Sprague‑Dawley rats were cultured to analyze the mRNA expression and release of CGRP. Calcium influx, as an indicator of TRPV1 activation, was measured in 293 cells with stable overexpression of TRPV1. The results demonstrated that the amount of CGRP in the cell culture supernatant and the mRNA expression of CGRPα and CGRPβ in DRG was upregulated by rutaecarpine in a concentration‑dependent manner, and was inhibited by the TRPV1 receptor antagonist capsazepine. In addition, intracellular Ca2+ levels were increased by Rut in the aforementioned 293 cell line, indicating the activation of TRPV1 by Rut. Therefore, it was concluded that TRPV1 was involved in the expression and release of CGRP stimulated by rutaecarpine, which provided novel mechanistic understanding of the treatment of hypertension using the Chinese herb Wu‑Chu‑Yu. [ABSTRACT FROM AUTHOR]

Lead-free ceramics 0.5BaCaTiO-0.5BaTiZrO- xIrO ( x = 0-1.2 %) were prepared at a low temperature of 1260 °C via sintering the as-synthesized nanoparticles, which were synthesized by a modified Pechini polymeric precursor method. All samples featured high levels of densification under the synthesis conditions; particularly, the ceramic prepared at IrO content of 0.4 % achieved the highest relative density (~97.4 %). Phase transition from tetragonal to orthorhombic and a polymorphic phase transition (PPT) region were observed, which were influenced by the IrO content. The dielectric properties, temperature coefficient of capacitance, ferroelectric properties, and piezoelectric properties as a function of IrO content were thoroughly studied. Optimal electrical properties (remnant polarization, piezoelectric constant, and planar electromechanical coupling factors, i.e., P = 6.28 μC/cm, d = 199 pC/N, and k = 0.258) were obtained around the PPT region. The findings of the ceramic electrical properties by IrO doping are believed to be insightful in the development of lead-free dielectric and ferroelectric materials. [ABSTRACT FROM AUTHOR]

Lead-free ceramics 0.50BaCaTiO-0.50BaTiZrO (BCT-BZT) were prepared via sintering BCT and BZT nanoparticles, which were synthesized using a modified Pechini polymeric precursor method, at a low temperature of 1260°C. The relative densities of the ceramics prepared with different zirconium contents ( x) were all above 95.3%, reaching a maximum of 97% when x = 0.08. X-ray diffraction results confirmed the onset of phase transformation from orthorhombic to rhombohedral symmetry with increasing zirconium contents, and the polymorphic phase transition was observed at x = 0.10. The dielectric dispersion, diffuse phase transition (DPT), and relaxor-like ferroelectric characteristics as a function of zirconium content were thoroughly studied. Optimum physical properties, remnant polarization ( P) = 16.4 μC/cm, piezoelectric constant ( d) = ~240 pC/N, and electromechanical coupling factor ( k) = 0.22, were obtained at x = 0.10. The findings of the current DPT behavior study of BCT-BZT ceramics are believed to be insightful to the development of ferroelectric materials. [ABSTRACT FROM AUTHOR]

Background: In general, the individual patient-level data (IPD) collected in clinical trials are not available to independent researchers to conduct economic evaluations; researchers only have access to published survival curves and summary statistics. Thus, methods that use published survival curves and summary statistics to reproduce statistics for economic evaluations are essential. Four methods have been identified: two traditional methods 1) least squares method, 2) graphical method; and two recently proposed methods by 3) Hoyle and Henley, 4) Guyot et al. The four methods were first individually reviewed and subsequently assessed regarding their abilities to estimate mean survival through a simulation study. Methods: A number of different scenarios were developed that comprised combinations of various sample sizes, censoring rates and parametric survival distributions. One thousand simulated survival datasets were generated for each scenario, and all methods were applied to actual IPD. The uncertainty in the estimate of mean survival time was also captured. Results: All methods provided accurate estimates of the mean survival time when the sample size was 500 and a Weibull distribution was used. When the sample size was 100 and the Weibull distribution was used, the Guyot et al. method was almost as accurate as the Hoyle and Henley method; however, more biases were identified in the traditional methods. When a lognormal distribution was used, the Guyot et al. method generated noticeably less bias and a more accurate uncertainty compared with the Hoyle and Henley method. Conclusions: The traditional methods should not be preferred because of their remarkable overestimation. When the Weibull distribution was used for a fitted model, the Guyot et al. method was almost as accurate as the Hoyle and Henley method. However, if the lognormal distribution was used, the Guyot et al. method was less biased compared with the Hoyle and Henley method. [ABSTRACT FROM AUTHOR]

Aims Vascular peroxidase 1 (VPO1) is a newly identified haem-containing peroxidase that catalyses the oxidation of a variety of substrates by hydrogen peroxide (H2O2). Considering the well-defined effects of H2O2 on the vascular remodelling during hypertension, and that VPO1 can utilize H2O2 generated from co-expressed NADPH oxidases to catalyse peroxidative reactions, the aims of this study were to determine the potential role of VPO1 in vascular remodelling during hypertension. Methods and results The vascular morphology and the expression of VPO1 in arterial tissues of spontaneously hypertensive rats and Wistar–Kyoto rats were assessed. The VPO1 expression was significantly increased concomitantly with definite vascular remodelling assessed by evaluating the media thickness, lumen diameter, media thickness-to-lumen diameter ratio and mean nuclear area in artery media in spontaneously hypertensive rats. In addition, in cultured rat aortic smooth muscle cells we found that the angiotensin II-mediated cell proliferation was inhibited by knockdown of VPO1 using small hairpin RNA. Moreover, the NADPH oxidase inhibitor, apocynin, and the hydrogen peroxide scavenger, catalase, but not the ERK1/2 inhibitor, PD98059, attenuated angiotensin II-mediated up-regulation of VPO1 and generation of hypochlorous acid. Conclusion VPO1 is a novel regulator of vascular smooth muscle cell proliferation via NADPH oxidase–H2O2–VPO1–hypochlorous acid–ERK1/2 pathways, which may contribute to vascular remodelling in hypertension. [ABSTRACT FROM PUBLISHER]

This paper presents a new chiral separation technology: two-phase (O/W) recognition chiral extraction. Distribution behavior of α-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D( L)-isobutyl tartrate in 1,2-dichloroethane organic phase and β-CD derivatives in aqueous phase, and the influence of the kind and concentration of extractant and pH on extraction performance was investigated. The experimental results indicate that two-phase (O/W) recognition chiral extraction is of strong chiral separation ability. HP- β-CD, HE- β-CD and Me- β-CD have higher recognition ability for S-CHMA than that for R-CHMA, among which HP-β-CD has the strongest ability; whereas, D-isobutyl tartrate has reversed recognition ability for them. In the extraction system containing HP- β-CD and D-isobutyl tartrate, e.e.% of S-CHMA in aqueous phase reached 27.6% by one stage extraction, and the distribution ratio for R-CHMA( k R ) and for S-CHMA( k s ) and separation factor (α) are 2.44, 0.89 and 2.49, respectively. Meanwhile, pH and concentration of extractant have great effects on chiral separation ability. Two-phase (O/W) recognition chiral extraction has great significance for preparative separation of racemic compounds. [ABSTRACT FROM AUTHOR]

Numerous studies have strongly suggested that flavonoids exhibit antimutagenic, anticarcinogenic, antiallergic, and anti-inflammatory properties, but the mechanism is still far from clear. In this study, the effect of natural flavonoid compounds, such as green tea polyphenol, epigallocatechin gallate, quercetin, and rutin on lipoxygenase-mediated co-oxidation of guaiacol, benzidine, paraphenylenediamine, and dimethoxybenzidine was investigated. Green tea polyphenol, epigallocatechin gallate, quercetin, and rutin can reduce the co-oxidation reaction speed of tested compounds mediated by soybean lipoxygenase and the production of oxidative products and free radical intermediates. Their median inhibition concentrations on guaiacol oxidation mediated by soybean lipoxygenase were 8.22 mg·L-1,17.8µmol·L-1, 41.5µmol·L-1, and 46.3 µmol·L-1, respectively. These were all significantly lower than glutathione, dithiothreitol, butylated hydroxyanisole and gossypol. The data collected in this study suggest that flavonoids may have an anticarcinogenicity and antitoxicity effect through inhibition of oxidative activation. [ABSTRACT FROM PUBLISHER]