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Metformin is known for its antioxidant properties and ability to ameliorate metabolic dysfunction-associated fatty liver disease (MAFLD) and is the focus of this study. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is linked to MAFLD risk. This study investigated the effects of metformin on ferroptosis in free fatty acid (FFA)-treated Huh7 hepatoma cells and its association with MAFLD risk. Using Western blot, immunofluorescence, and ELISA, this study revealed that FFA treatment led to increased intracellular fat and iron accumulation, heightened Lp-PLA2 expression, reduced levels of the cysteine transporter SLC7A11 and glutathione peroxidase 4 (GPX4), altered glutathione (GSH)/oxidized glutathione (GSSG) ratios, generation of reactive oxygen species (ROS), and initiation of lipid peroxidation, which ultimately resulted in cell ferroptosis. Importantly, metformin reversed FFA-induced iron accumulation, and this effect was attenuated by ferrostatin-1 but enhanced by erastin, RSL3, and si-GPX4. Additionally, metformin activated antioxidant and antiapoptotic mechanisms, which reduced lipid peroxidation and suppressed Lp-PLA2 expression in FFA-treated Huh7 cells. In conclusion, our findings indicate that metformin may protect against MAFLD by inhibiting iron accumulation and Lp-PLA2 expression through the ROS, ferroptosis, and apoptosis signaling pathways. This study highlights potential therapeutic strategies for managing MAFLD-related risks and emphasizes the diverse roles of metformin in maintaining hepatocyte balance. KEY POLICY HIGHLIGHTS: Metformin lowered Lp-PLA2 levels in human Huh7 hepatoma cells. Both fatty acid and iron metabolism improved after metformin treatment. Metformin alleviated oxidative stress, apoptosis, lipid peroxidation and ferroptosis. [ABSTRACT FROM AUTHOR]

The crystal appearance of industrial grade 2,6-bis(picrylamino)-3,5-dinitropyridine (PYX) was mostly needle-shaped or rod-shaped with an average aspect ratio of 3.47 and roundness of 0.47. To improve the loading density and pressing safety, the crystal shape of PYX was optimized by cooling crystallization method. After recrystallization, the aspect ratio decreased from 3.47 to 1.28, and the roundness value increased from 0.47 to 0.78. XRD data showed that there is no crystal pattern change before and after recrystallization. The friction sensitivity of the explosive decreases from 88% to 56%, and the impact sensitivity decreases from 76% to 12%. Differential scanning calorimeter (DSC) was used to study the thermal decomposition of PYX. The thermal decomposition peak temperature of the samples after recrystallization was 4~7℃ higher than that of raw PYX. The adiabatic induction time (TMRad) and self-accelerating decomposition temperature (SADT) were calculated with AKTS software. In the same adiabatic induction time, the initial temperature of recrystallization PYX is about 30℃~40℃ higher than that of the raw PYX. The SADT is increased by about 50℃~60℃. The thermal safety of recrystallized PYX is improved. [ABSTRACT FROM AUTHOR]

This article comprehensively reviews how cerebral hypoxia impacts the physiological state of neurons and dendritic spines through a series of molecular changes, and explores the causal relationship between these changes and neuronal functional impairment. As a severe pathological condition, cerebral hypoxia can significantly alter the morphology and function of neurons and dendritic spines. Specifically, dendritic spines, being the critical structures for neurons to receive information, undergo changes such as a reduction in number and morphological abnormalities under hypoxic conditions. These alterations further affect synaptic function, leading to neurotransmission disorders. This article delves into the roles of molecular pathways like MAPK, AMPA receptors, NMDA receptors, and BDNF in the hypoxia-induced changes in neurons and dendritic spines, and outlines current treatment strategies. Neurons are particularly sensitive to cerebral hypoxia, with their apical dendrites being vulnerable to damage, thereby affecting cognitive function. Additionally, astrocytes and microglia play an indispensable role in protecting neuronal and synaptic structures, regulating their normal functions, and contributing to the repair process following injury. These studies not only contribute to understanding the pathogenesis of related neurological diseases but also provide important insights for developing novel therapeutic strategies. Future research should further focus on the dynamic changes in neurons and dendritic spines under hypoxic conditions and their intrinsic connections with cognitive function. [ABSTRACT FROM AUTHOR]

Lithium metal‐graphene host composite is a promising anode material for high‐energy‐density Li battery owing to its three‐dimensional structure, micro‐level controllable thickness and ultrahigh specific capacity. However, we discover that the hydroxyl/carboxyl functional groups in the reduced graphene oxide (rGO) host are likely to be reduced into lithium carbonate composition in the solid‐electrolyte interphase (SEI), which resulted in severe lithium dendrite growth that deteriorate its electrochemical performances. Here, we develop a magnesium anchoring strategy that selectively bond the Mg ion with the hydroxyl/carboxyl groups in rGO host, generating an electrolyte‐derived lithium fluoride‐dominant SEI instead of oxygen groups‐derived, lithium carbonate‐dominant SEI. By anchoring 0.60% of Mg in the rGO host using a facile compositing‐pyrolysis approach, Li dendrite growth in anode can be significantly suppressed, and the cycling stability of Li metal full cells can be prolonged by 200%. These findings give new insight into the mechanism of SEI formation in Li metal anode, and provide a new design strategy for restraining the reduced reaction of hydroxyl/carboxyl groups in graphene to stabilize the composite anode of lithium metal battery. [ABSTRACT FROM AUTHOR]

In this study, the influence of the physicochemical properties and proportioning conditions of metakaolin on the mechanical properties of the synthesized metakaolin geopolymers was comprehensively evaluated, and the issue of the reaction control mechanism for the formation of mechanical properties during the synthesis of geopolymers was addressed. The reaction mechanism was analyzed by SEM and FTIR, and the kinetic analysis of the geopolymerization process was carried out using isothermal calorimetry combined with the Jander model. The test results show that the physicochemical properties of the metakaolin and the proportioning conditions together affect the mechanical properties of the geopolymer, with the correlation between the active aluminum content of the metakaolin and the strength of the geopolymer reaching over 0.87. The early stages of the geopolymerization reaction are all controlled by nucleation–growth mechanisms (N < 1), and the variability in control mechanisms is mainly found in the later stages of the geopolymerization reaction. The low reactivity and slow exothermic hydration of metakaolin are more inclined to the nucleation-growth mechanism responsible for the hydration process due to the large amount of encapsulation. [ABSTRACT FROM AUTHOR]

The construction of a Z‐scheme photocatalytic system is significant in realizing efficient water splitting for hydrogen (H2) evolution. Herein, a novel donor–acceptor covalent organic polymer (COP) is introduced to construct a COP‐ZnIn2S4 (ZIS) heterostructure via in situ condensation reaction. The COP‐ZIS heterostructure with platinum (Pt) as cocatalyst delivers a high hydrogen evolution rate of 5.04 mmol g−1 h−1, which is 16 and 3 times higher than ZIS and Pt/ZIS, respectively. The built‐in field between the highest occupied molecular orbital of COP and the valence band (VB) of ZIS forms a Z‐scheme heterostructure, realizing efficient charge separation. Based on density functional theory calculations, the porphyrin molecule in COP act as electron donor that provides compensating electrons to ZIS. The cocatalyst boosts the utilization of electrons in ZIS. The rate‐limiting steps for H2 evolution with ZIS are overcome by improving charge separation with the Z‐scheme heterostructure and speeding up the reaction with cocatalyst. Therefore, the COP‐ZIS heterostructure with Pt exhibits optimized H2 evolution. This study will inspire to construct novel organic and inorganic Z‐scheme photocatalysts for efficient green energy production. [ABSTRACT FROM AUTHOR]

A pivotal limitation in the widespread adoption of geopolymer stems from their notable and substantial drying shrinkage properties, which significantly constrain their potential applications. The complex reaction processes and amorphous gel structures make it difficult to quantitatively calculate the drying shrinkage rate. In this study, alkali-activated slag-metakaolin-based geopolymer was used to develop a method for predicting drying shrinkage. By analyzing the internal relative humidity changes, contact angles on the structure surface at different ratios, and the surface tension of pore solutions, the capillary tensile stress within the structure was calculated. This analysis was combined with measurements of drying shrinkage, elastic modulus, and porosity to establish a predictive method for the drying shrinkage of alkali-activated slag-metakaolin-based geopolymer. The results indicated that as the system's relative humidity decreased, the surface tension of the pore solution increased, the interface contact angle reduced, and the capillary tensile stress, as calculated using the Young-Laplace equation, increased. These changes intensified the microstructural shrinkage and, consequently, increased the geopolymer's overall shrinkage rate. At the same time, the larger the porosity of the geopolymer system, the smaller the elastic modulus, the larger the dry shrinkage rate of the geopolymer. At a porosity of 29.0 %, an elastic modulus of 1.83 GPa, and a capillary tensile stress of 3.6 MPa, the dry shrinkage of the geopolymer is only 0.899 %. By adjusting the porosity and elastic modulus to 38.3 % and 1.60 GPa, respectively, and increasing the capillary tensile stress to 10.84 MPa, the dry shrinkage of the geopolymer reaches a maximum of 1.942 %. The prediction method for geopolymer drying shrinkage, established based on these factors, has a correlation coefficient of 0.97, effectively predicting the trend of geopolymer drying shrinkage rate characteristics. The current study provides a theoretical basis for methods to reduce shrinkage in geopolymers and their application in engineering. • The drying shrinkage performance of Alkali-activated Slag Metakaolin (ASM) based geopolymer was studied. • Drying shrinkage is quantified by capillary pulling force. • Propose a method to predict the drying shrinkage of ASM-based geopolymer under multi-factor conditions. [ABSTRACT FROM AUTHOR]

Comparative proteomics and non-target metabolomics, together with physiological and microstructural analyses of wheat grains (at 15, 20, 25, and 30 days after anthesis) from two different quality wheat varieties (Gaoyou 5766 (strong-gluten) and Zhoumai 18) were performed to illustrate the grain filling material dynamics and to search for quality control genes. The differential expressions of 1541 proteins and 406 metabolites were found. They were mostly engaged in protein metabolism, stress/defense, energy metabolism, and amino acid metabolism, and the metabolism of stored proteins and carbohydrates was the major focus of the latter stages. The core proteins and metabolites in the growth process were identified, and the candidate genes for quality differences were screened. In conclusion, this study offers a molecular explanation for the establishment of wheat quality, and it aids in our understanding of the intricate metabolic network between different qualities of wheat at the filling stage. [Display omitted] • Different quality wheat exhibit variations in indicators, protein, and starch development. • Proteomics and metabolomics of different quality wheat were analyzed in combination. • Selected some important proteins and metabolites during the wheat filling process. • Selected some possible gluten quality differential proteins (genes). [ABSTRACT FROM AUTHOR]

In order to improve the efficiency of commercial banks user data management on big data platform, on the basis of in-depth study on the classification of user business data, related attributes and correlation of corresponding data sets, the big data cluster technology is developed to define the bank customer account and correspond log data table, organize user data via the relational data platform, and conduct relational management of the customer data based on its account. By analyzing the related business data table of sample customers, a physical storage sub set, containing multiple log data, is designed and tested to achieve the joint access to the man and log table. Results show that the retrieval time for target data is shortened, and the efficiency of data management is improved. [ABSTRACT FROM AUTHOR]

A new carotane sesquiterpenoid, methyl gymnabloate (1), was isolated from the fermentation broth of the wild macrofungus Gymnopus sp. 0612-9. Its structure was elucidated by analysis of extensive spectroscopic data. The antifungal activity against Penicillium italicum and Penicillium citrinum were evaluated. Compound 1 showed moderate activities against the pathogens P. italicum and P. citrinum. [ABSTRACT FROM AUTHOR]

Background: The recent emergence and dissemination of high-level mobile tigecycline resistance Tet(X) challenge the clinical effectiveness of tigecycline, one of the last-resort therapeutic options for complicated infections caused by multidrug-resistant Gram-negative and Gram-positive pathogens. Although tet(X) has been found in various bacterial species, less is known about phylogeographic distribution and phenotypic variance of different genetic variants. Methods: Herein, we conducted a multiregional whole-genome sequencing study of tet(X)-positive Acinetobacter isolates from human, animal, and their surrounding environmental sources in China. The molecular and enzymatic features of tet(X) variants were characterized by clonal expression, microbial degradation, reverse transcription, and gene transfer experiments, while the tet(X) genetic diversity and molecular evolution were explored by comparative genomic and Bayesian evolutionary analyses. Results: We identified 193 tet(X)-positive isolates from 3846 samples, with the prevalence ranging from 2.3 to 25.3% in nine provinces in China. The tet(X) was broadly distributed in 12 Acinetobacter species, including six novel species firstly described here. Besides tet(X3) (n = 188) and tet(X4) (n = 5), two tet(X5) variants, tet(X5.2) (n = 36) and tet(X5.3) (n = 4), were also found together with tet(X3) or tet(X4) but without additive effects on tetracyclines. These tet(X)-positive Acinetobacter spp. isolates exhibited 100% resistance rates to tigecycline and tetracycline, as well as high minimum inhibitory concentrations to eravacycline (2–8 μg/mL) and omadacycline (8–16 μg/mL). Genetic analysis revealed that different tet(X) variants shared an analogous ISCR2-mediated transposon structure. The molecular evolutionary analysis indicated that Tet(X) variants likely shared the same common ancestor with the chromosomal monooxygenases that are found in environmental Flavobacteriaceae bacteria, but sequence divergence suggested separation ~ 9900 years ago (7887 BC), presumably associated with the mobilization of tet(X)-like genes through horizontal transfer. Conclusions: Four tet(X) variants were identified in this study, and they were widely distributed in multiple Acinetobacter spp. strains from various ecological niches across China. Our research also highlighted the crucial role of ISCR2 in mobilizing tet(X)-like genes between different Acinetobacter species and explored the evolutionary history of Tet(X)-like monooxygenases. Further studies are needed to evaluate the clinical impact of these mobile tigecycline resistance genes. [ABSTRACT FROM AUTHOR]

The selective feeding of plants and excavation of soil by small mammals, especially rodents, have important effects on plant-animal interactions, but few studies have explored these effects and their potential mechanisms. In the present study, large-scale enclosure manipulative experiments were performed to explore the effects of Brandt's vole (Lasiopodomys brandtii) on plant community composition and soil nutrients in Inner Mongolia, China. The results suggested that Brandt's vole significantly decreased community biomass compared to the control enclosure, reducing it by 21.42% at the end of the experiments. Further analysis showed that the rhizome grass biomass was significantly reduced by 86.82%, while the biomass of bunch grasses and forbs was higher in the vole enclosure by 18.35% and 49.64%, respectively. Furthermore, Brandt's vole significantly decreased species richness and the density, coverage, and importance value of the main forage species available. However, the soil main nutrient content and ammonium nitrogen mineralization rate were not significantly affected by the presence of Brandt's vole, whereas nitrification rate significantly increased in the vole enclosure. Finally, we conclude that Brandt's vole activity may affect the species' habitat quality by creating plant communities dominated by less preferred forage species. [ABSTRACT FROM AUTHOR]

A new [Co21(H2O)4(OH)12]30+ unit-incorporating polyoxotungstate, Na18[Co(H2O)6]2{[Na(H2O)4]2[Na(H2O)2]2[Co(H2O)3]2[Co21(H2O)4(OH)12](SiW10O37)6}·24H2O (denoted as Co25Si6W60), has been hydrothermally synthesized and fully characterized via elemental analyses, thermogravimetric analysis, bond valence sum (BVS) calculations, IR spectrum, UV-vis spectrum, diffuse reflectance spectrum, powder X-ray diffraction and single-crystal structural analysis. The most remarkable feature is that the gigantic [Co21(H2O)4(OH)12(SiW10O37)6]30− core in Co25Si6W60 is composed of a square-like [Co21(H2O)4(OH)12]30+ nanosheet encapsulated by six dilacunary Keggin [α-SiW10O37]10− moieties in a staggered fashion, resulting in a remarkable sandwich-type assembly. Furthermore, the unique Co25Si6W60-based biosensing system, as a simple, rapid, and highly sensitive electrochemical platform, offers an environmentally friendly route for detecting dichlorvos in the field of both food safety and environmental pollution. [ABSTRACT FROM AUTHOR]

Rare earth element (La and Y) doped FeOCl has been successfully prepared, which shows efficient Fenton catalytic activity for ibuprofen degradation under simulated solar light. The degradation constants of FeOCl/La and FeOCl/Y in photo-Fenton catalysis are a factor of 7.12 and 5.21 times higher than that of FeOCl, respectively. According to DFT calculations, the doping of rare earth elements formed new catalytically active sites, which promoted the production of ˙OH radicals. The improved separation efficiency of photogenerated electron hole pairs in FeOCl/Ln (Ln = La or Y) also promotes the decomposition of H2O2 to produce ˙OH radicals. A synergistic mechanism for FeOCl/Ln (Ln = La or Y) is proposed for the enhanced catalytic performance. [ABSTRACT FROM AUTHOR]

• Bond strength between the geopolymer and aggregate is higher compared to cement. • Bond strength decreases with increase of activator modulus and liquid/solid ratio. • The microhardness of ITZ is lower than that of the geopolymer binder. • The crack width in ITZ increases with activator modulus and liquid/solid ratio. • The microhardness of ITZ decreases with activator modulus and liquid/solid ratio. The application of geopolymers as an alternative to Portland cement has received significant attention in concrete development due to the promotion of sustainability. Interfacial transition zone (ITZ) has been characterized as the weakest link in ordinary Portland cement concrete and usually deteriorates the mechanical properties and durability of concrete. To further understand the performance of geopolymeric concrete, the microstructure and properties of the interface zone in geopolymeric concrete are investigated in this study. Metakaolin and ground granulated blast-furnace slag (GGBFS) were used as the raw materials for geopolymer synthesis. Cubic splitting tests were conducted to investigate the interfacial bond strength between the geopolymer and the granite aggregate for different activator moduli and liquid/solid ratios. The morphology and mechanical properties of the ITZ between the geopolymer and granite aggregate were studied with the aids of scanning electron microscopy, energy-dispersive X-ray spectroscopy, and microhardness testing. The results indicate that the bond strength between the geopolymer and aggregate is higher than that between the cement paste and granite aggregate, and it decreases with the increase of the activator modulus and liquid/solid ratio. An ITZ was observed between the geopolymer paste and granite aggregate, and its microstructure and chemical components were different from those of the geopolymer. Obvious inhomogeneity can be observed for the ITZ along the aggregate body. The microhardness of the ITZ is lower than that of the geopolymer binder, and an increase in the activator modulus and liquid/solid ratio leads to an increase in the width of the crack in the ITZ and a decrease in the microhardness. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • ZnO/carbon nanotube composites as anode materials are synthesized by physical mixing and chemical filling methods. Electrochemical performance of the Ni-Zn batteries synthesized by chemical filling method is far better than that by the physical mixing method • The discharge capacity and cycle life of the newly designed Ni-Zn batteries can reach 410 mAh/g and 600 times, respectively. Abstract The cycle life of Ni-Zn secondary batteries is largely affected by the dissolution of zinc anode active substances. ZnO/carbon nanotube composites as anode materials are synthesized by physical mixing and chemical filling methods to reduce the dissolution of active substances and improve the electrochemical performance of Ni-Zn batteries. By performing electrochemical testing to the Ni-Zn batteries with anode materials of ZnO/carbon nanotube composites prepared by the two different synthesis methods, we find that the electrochemical performance of the Ni-Zn batteries with anode materials of ZnO/carbon nanotube composites synthesized by chemical filling method is far better than that synthesized by the physical mixing method, with discharge capacity of 410 mA h/g and achievable cycle life of about 600 times. The experimental results pave the way for applications of carbon nanomaterials to the optimal design of zinc anode of Ni-Zn secondary batteries. [ABSTRACT FROM AUTHOR]

• A novel fault measure and early warning system for air compressor is proposed. • PCA-BP based variable selection are applied to simplify the MEST model. • A deviation function is defined to calculated the deviation sequence. • Sliding window method is applied to determine the fault early warming threshold. Air compressor is a main power equipment, and improving its reliability and security is important to enhance the competitiveness of pneumatic companies. This study proposes a real monitored data-based fault measure and early warning system for air compressor, which can guide field workers in economically and safely operating the air compressor by finding and dealing with faults ahead of time. A data-driven multivariate state estimation technique (MSET) is utilized to construct the non-parametric fault early warning model under normal operating condition, principal components analysis (PCA) and back propagation (BP) method are combined to construct the dynamic memory matrix and simplify the model. With the pre-built PCA-BP-MSET model, optimal values of the observed vectors are estimated and a deviation function is defined to calculated the deviation sequence between the estimated and observed vectors, where the qualitative-quantitative combined AHP method is adopted to determine the weights of the monitored variables. With the deviation sequence, the sliding window statistical method is applied to determine the fault early warming threshold, which can be used as a benchmark to measure and warn the fault of air compressor. The fault warning information of an air compressor is given out once the deviation degree of some observed vector exceeds the threshold, thereby realizing the function of fault measure and early warning in advance. In addition, an automatically updating method is proposed to ensure the accuracy of the PCA-BP-MSET model in case of the changes of running states. For verification, a real fault case of an air compressor has been chosen to verify the effectiveness of the proposed method. Result shows that the PCA-BP-MSET-based method can catch the fault developing process timely, which is appropriate for the faults prevention and rapid troubleshooting of air compressor. [ABSTRACT FROM AUTHOR]

Abstract Mineral resources are still the rigid demand of China's development and their sustainability assessment is central to regional development. This paper introduces an improved Analytic Hierarchy Process-based Normal cloud model which incorporated randomness and fuzziness and presents an index system applicable to empirical analysis on 31 provinces of China. The weight system of evaluation indicators is determined by an improved analytic hierarchy process (IAHP) approach with good accessibility and attainability. Regional disparities of resources sustainability are demonstrated by spatial distributions of mineral resources sustainability with the help of GIS technology. The sustainability level is determined by the combination of resources, environment and society dimensions. The results indicate that the areas with high sustainability do not necessarily happen in resource-rich regions. The most important implications are the relatively lower sustainability of the developed areas and the higher sustainability in western provinces. The scores for indicators reveal that compared with western and central areas, the coastal provinces are less sustainable in environmental carrying capacity, but with higher sustainable social supporting capacity. Robustness test notes that the results are sensitive to the adjustment of weight system due to the preference of decision makers. Finally, differentiated regional strategies for improving overall sustainability are proposed. Graphical abstract Image Highlights • Normal cloud model is applied to assess sustainability of mineral resources (SMR). • An assessment system of SMR is developed for Chinese province. • The weights are obtained by improved analytic hierarchy process and an expert survey. • Resource-rich areas have high levels of SMR but with some exceptions. • Regional SMR is sensitive to the preference of decision makers. [ABSTRACT FROM AUTHOR]

Highlights • A novel porphyrin-based porous organic polymer (PPOP) is designed and prepared. • Large surface area with adequately exposed catalytic active sites of the PPOP ensures its high peroxidase-like activity. • A versatile colorimetric biosensor for H 2 O 2 , glucose and three antioxidants detection with high sensitivity and stability is established with PPOP. • The distinguishing inhibitory behaviors of three antioxidants to PPOP imply different antioxidative mechanisms. Abstract As promising alternatives to natural enzymes, catalytically active nanomaterials (nanozymes) are of great interest due to their high activity, controlled synthesis, low-cost, and excellent stability against stringent conditions. Studies of the chemical interactions between antioxidants and nanozymes would provide valuable information about catalytic mechanisms, help to better understand some metabolic pathways and screen more effective artificial enzymes. In this work, a porphyrin-based porous organic polymer, named FePPOP-1 was synthesized via a Sonogashira–Hagihara coupling reaction between 1,3,5-triethynylbenzene and iron 5,10,15,20-tetrakis-(4′-bromophenyl)porphyrin (FeTBrPP). FePPOP-1 possesses large BET surface area as well as high thermal and chemical stability. The good peroxidase-like activity of FePPOP-1 was confirmed by catalyzing the oxidation reaction of 3,3′,5,5′-Tetramethylbenzidine (TMB) with H 2 O 2. A FePPOP-1 based colorimetric biosensor was then established for H 2 O 2 , glucose and three antioxidants [ascorbic acid (AA), gallic acid (GA) and tannic acid (TA)] detection with high sensitivity and stability. Moreover, the inhibitory effects of these three natural antioxidants on peroxidase-like activity of FePPOP-1 and the relative strength of their anti-oxidative capacity were comparatively investigated. The distinguishing inhibitory behavior of AA, GA and TA implied their different anti-oxidative mechanisms. [ABSTRACT FROM AUTHOR]

In this work, a facile strategy for embedding graphene (GR) nanosheets into carbon-coated MoSe 2 (MoSe 2 @C@GR) hybrid nanofibers has been developed by a simple electrospinning route. One dimensional nanofibers have excellent structural stability resulting from strong tolerance to stress change. The highly conductive graphene nanosheets play an excellent coating effect on MoSe 2 to inhibit the growth of MoSe 2 nanosheets on the nanofiber surface and enhance the conductivity of hybrid nanofibers, which substantially improves the rate performance and cycle stability of carbon-coated MoSe 2 (MoSe 2 @C) nanofibers. In particular, the MoSe 2 @C@GR electrode delivers a high discharge capacity of 366.9 mAh g −1 after 200 cycles at 0.2 A g −1 , meanwhile exhibits superior rate performance. The analysis of Nyquist plots reveals that the addition of graphene nanosheets can greatly strengthen the kinetics of electrode reaction and the electrochemical activity. [ABSTRACT FROM AUTHOR]

Background In recent years, many studies have demonstrated that endogenous adenosine induced by ischemia postconditioning reduces apoptosis in animal and cell models, but no study has clearly elucidated the effects of hypoxia postconditioning (HPC) in human dermal microvascular endothelial cells (HDMECs) of flaps, and the subtype of adenosine receptors involved remains unknown. In our study, we sought to identify the roles of adenosine A 2a receptor, NDRG3 (N-myc downstream-regulated gene 3) and Raf-ERK pathway in the anti-apoptotic effects of hypoxia postconditioning. Methods Human dermal microvascular endothelial cells were put into a hypoxic incubator (94% N 2 + 5% CO 2 + 1% O 2 ) for 8 h (hypoxia), and followed 24 h of normoxic culture with 95% air and 5% CO 2 (reoxygenation). Hypoxia postconditioning model of HDMECs was achieved as follows: Before HDMECs were put into a normoxic incubator, HDMECs were treated by three cycles of 5 min of brief reoxygenation and 5 min of re-hypoxia. Opening level of mitochondrial permeability transition pore and change of mitochondrial membrane potential were detected with related Kit. The protein expressions of mitochondrion apoptosis, adenosine A 2a receptor and NDRG3-Raf-ERK pathway were measured by western blot. Result Hypoxia/reoxygenation (H/R) resulted in injury in HDMRCs as evidenced by an increase in apoptosis percentage, mitochondrial membrane permeability and an increase in expression of pro-apoptosis proteins (Bax, c-caspase-3 and cytochrom C), meanwhile, hypoxia/reoxygenation increased expression of A 2a receptor, NDRG3, p- c -Raf, p -ERK, which was significantly attenuated by hypoxia postconditioning treatment. Moreover, Hypoxia/reoxygenation (H/R) resulted in a decrease in expression of anti-apoptotic protein (Bcl-2). However, the protective effect of hypoxia postconditioning treatment could be inhibited by adding CGS21680, a selective adenosine A 2a receptor agonist (all P values < 0.05). [ABSTRACT FROM AUTHOR]

Reflection full-waveform inversion (RFWI) updates the low- and highwavenumber components, and yields more accurate initial models compared with conventional full-waveform inversion (FWI). However, there is strong nonlinearity in conventional RFWI because of the lack of low-frequency data and the complexity of the amplitude. The separation of phase and amplitude information makes RFWI more linear. Traditional phase-calculation methods face severe phase wrapping. To solve this problem, we propose a modified phase-calculation method that uses the phase-envelope data to obtain the pseudo phase information. Then, we establish a pseudophase-information-based objective function for RFWI, with the corresponding source and gradient terms. Numerical tests verify that the proposed calculation method using the phase-envelope data guarantees the stability and accuracy of the phase information and the convergence of the objective function. The application on a portion of the Sigsbee2A model and comparison with inversion results of the improved RFWI and conventional FWI methods verify that the pseudophase-based RFWI produces a highly accurate and efficient velocity model. Moreover, the proposed method is robust to noise and high frequency. [ABSTRACT FROM AUTHOR]

Subarrayed monopulse linear and conformal circular arc arrays with low-sidelobe sum and difference patterns are synthesized. For the monopulse array with a subarray partition consisting of contiguous elements to reduce the cross points, the synthesis problem is first formulated as a constrained optimization problem. Then, by defining an appropriate fitness function to convert the problem into an unconstrained one, the problem is efficiently solved by the differential evolution algorithm under successful-parent-selecting framework. The numerical results of small and large monopulse linear arrays are reported by comparisons with the state-of-the-art techniques. At last, synthesis of a monopulse conformal circular arc array is also investigated based on the same technique. [ABSTRACT FROM AUTHOR]

A loaded wideband tapered slot antenna (TSA) with broad beamwidth and enhanced front-to-back ratio (FBR) is proposed. The antenna is obtained by adding a series of loading structures to a traditional microstrip-fed linearly TSA (LTSA). The performance of the antenna with different loading structures has been discussed. Finally, the antenna is manufactured and measured. The measured results show good performance of impendence bandwidth is approximately 82.2% (4.3-10.3 GHz) for VSWR ≤ 2, while a pattern bandwidth of 50.4% (4.3-7.2 GHz) for more than 100° 3-dB beamwidth (HPBW) both in E-plane and H-plane is obtained. Moreover, a new method for FBR improvement is presented and a moderately high average FBR (AFBR) about 19 dB is obtained in the pattern band. The simulated results agree with the measured results. All above indicates that the proposed antenna cannot only be used in wireless communication, but also as antenna unit of wide-scan phased array antennas (WSPAAs). [ABSTRACT FROM AUTHOR]

Stichopus japonicus Polysaccharide (SJP) is a sulfated polysaccharide from the body wall of the sea cucumber, Stichopus japonicus. Fucoidan is a heparinoid compound that belongs to a family of sulfated polyfucose polysaccharides. Heparin is a glycosaminoglycan. SJP, fucoidan, and heparin profoundly promoted stromal cell-derived factor 1 alpha (SDF-1α)-induced neural stem cell (NSC) migration in a concentration-dependent manner. In addition, the basal migration capacity of cells was significantly promoted after incubation with SJP, fucoidan, or heparin. Interaction of SJP, fucoidan, or heparin with SDF-1α efficiently showed additive effects on the promotion of cell migration from the neurosphere. SJP, fucoidan, or heparin interaction with SDF-1α treatment could increase Nestin expression. SDF-1α modulated by SJP, fucoidan, or heparin activated the CXCR4 receptor and directed cellular migration via the activation of the PI3K/Akt/FOXO3a signaling pathway. Moreover, interaction of SJP, fucoidan, or heparin with SDF-1α effectively promoted NSC migration and induced SDF-1α and CXCR4 expressions. Results suggested that SJP, fucoidan, and heparin might be good candidates for alleviating injury-initiated signals to which NSCs respond. [ABSTRACT FROM AUTHOR]

The present study describes a positive regulatory loop between SJP and the SDF-1α/CXCR4 axis in NSC migration. The treatment of NSCs with SJP and SDF-1α increases the cell migration capacity and promotes cell migration from the neurospheres. These effects are accompanied by the up-regulation of Nestin, N-cadherin, TLR4, TNF-α, Cyclin D1, EGFR, Alpha 6 integrin, MMP-2, MMP-9, and iNOS, including SDF-1α and CXCR4 themselves. However, these effects are blocked by AMD3100, LY294002, U0126, and PDTC. SJP enhances the SDF-1α/CXCR4 axis-induced MMP-2 and MMP-9 secretion and NO release. Results demonstrate that interaction of SJP with the SDF-1α/CXCR4 axis regulates NSC migration via the PI3K/Akt/FOXO3a, ERK-MAPK, and NF-κB signaling pathways. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the protective effect and molecular mechanism of the sulfated polysaccharide (SJP) isolated from the sea cucumber Stichopus japonicus against 6-OHDA-induced toxicity in SH-SY5Y cells. The results showed that SJP could protect SH-SY5Y cells against 6-OHDA-induced cell injury. We found that SJP effectively improves cell viability, decreases LDH leakage, and reverses morphological damage. Moreover, SJP significantly increases SOD activity but decreases MDA levels and ROS generation. Effect of SJP on 6-OHDA-induced cell death in SH-SY5Y cells is associated with an arrest in the G1/S phase of the cell cycle and inhibits the expression of Cyclin D3. 6-OHDA-induced intracellular generation of ROS and mitochondrial dysfunctions, release of cytochrome c , imbalance of Bax/Bcl-2, cleaved caspase-9/caspase-9 and cleaved caspase-3/caspase-3 ratio, and p-p53 activation were strikingly attenuated by SJP pretreatment. Meanwhile, SJP counteracted NF-κB activation, thereby preventing up-regulation of iNOS and intracellular NO release. The data provide the first evidence that SJP protects SH-SY5Y cells against 6-OHDA toxicity possibly by inhibiting MAPK and NF-κB and activating PI3K/Akt signaling pathways. Thus, SJP is a candidate for further evaluation of its protective effects against neurodegeneration in PD. [ABSTRACT FROM AUTHOR]

In this report, the sulfated polysaccharide (SJP) isolated from the sea cucumber Stichopus japonicus can protect PC12 from NaSO-induced hypoxia/reoxygenation (H/R) injury. SJP effectively improves cell viability and reduces extracellular LDH release in PC12 cells after H/R. Moreover, SJP significantly increases SOD activity but decreases MDA levels. Our experiments showed that SJP could significantly reduce cell apoptosis caused by H/R. Our current results demonstrate that SJP suppressed the activation of MAPKs, resulting in a significant decrease in Bax/Bcl-2 ratio, cleaved caspase-3/caspase-3, p53 phosphorylation, and cytochrome c release in a concentration-dependent manner. MAPK is closely related to H/R injury. SJP inhibited JNK1/2 and p38 MAPK activation but did not affect the increased ERK1/2 expression. These results suggested that JNK1/2 and p38 MAPK pathways could be involved in SJP-mediated attenuation of PC12 H/R injury. SJP prevented PC12 H/R injury in a dose-dependent manner, indicating that SJP may be developed as a candidate drug to prevent or treat cerebral ischemia-reperfusion injury. [ABSTRACT FROM AUTHOR]

In the actual production, measuring the complexity of set point signals for a control system has practical significance. This paper proposes a new method for the complexity measure aiming mostly at set points of a system. Firstly, a standard SISO (Single Input Single Output) system is built as the complexity test system. Complexity index of a set point signal is defined based on the IAE (Integrated Absolute Error) performance. Then, a general complexity measure method is introduced for common set point signals. At last, complexity of some common set points and the AGC (Automatic Generation Control) orders for a power plant are analyzed. Tests and comparisons of the new method with two traditional methods (Lempel–Ziv complexity approach and Sample Entropy-Based approach) have shown that the IAE-based measure method introduced in this paper is reasonable and suitable for the complexity measurement of a set point signal in a control system. [ABSTRACT FROM AUTHOR]

The main purpose of this work was to develop and evaluate a self-emulsifying drug delivery system (SEDDS) of piperine to enhance its solubility and bioavailability. The formulation was optimized by solubility test and ternary phase diagrams. Then physiochemical properties and in vitro release of SEDDS were characterized. In vivo pharmacokinetics study and in situ single-pass intestinal perfusion were performed to investigate the effects of SEDDS on the bioavailability and intestinal absorption of piperine. The optimized formulation was composed of ethyl oleate, Tween 80 and Transcutol P (3:5.5:1.5, w/w), with the level of the piperine reached 2.5% (w/w). The in vitro dissolution rates of piperine SEDDS were significantly higher than the self-prepared capsules. In vivo pharmacokinetic study showed Cmax1, Cmax2 and area under the curve of piperine after oral administration of SEDDS in rats were 3.8-, 7.2- and 5.2-fold higher than the self-prepared capsules, respectively, and the relative bioavailability of SEDDS was 625.74%. The in situ intestinal absorption study revealed that the effective permeability and the effective absorption rate values of piperine for SEDDS were significantly improved comparing to solutions (p < 0.01). So SEDDS formulation could improve the oral bioavailability and intestinal absorption of piperine effectively. [ABSTRACT FROM AUTHOR]

A combined wind tunnel and water flume experiment was performed to study the effect of an aquatic herbaceous plant patch on the turbulent structure and flow field of wind-induced currents. Eel grass was chosen as the test plant. The plants were settled in patch form. Three-dimensional instantaneous velocities were measured using an acoustic doppler velocimeter (ADV). The results indicate that in the non- eel grass patch flow, turbulent shear stress − u ′ w ′ ¯ has a local minimum near the flow reverse point, turbulent intensity has the tendency to decrease continually from surface to bottom, and the dominant turbulent event is sweeping. In the eel grass patch with wind-induced flow, reverse flow occurs more quickly than in the non- eel grass patch case, and the reverse point shifts downward. Turbulent shear stress − u ′ w ′ ¯ has two maxima below the canopy. Turbulent intensity u ′ 2 ¯ decreases generally from water surface to flume bed, but there are maxima below the canopy. The dominant turbulent event is the fourth quadrant event below the canopy, and the two relative contributions of the second and the fourth quadrant event have similar values above the canopy. The mean bias and RMS values at centre of the eel grass patch are almost as two times larger as that at other measuring lines in non- eel grass region. This indicates that not only the shear stress and turbulent intensity become larger, and the vertical variations of the shear stress and turbulent intensity are also larger due to the effect of vegetation. The differences in the effects of submerged herbaceous vegetation on open channel flow and wind-induced flow were discussed in relation to time averaged velocity, turbulent shear stress, turbulent intensity and coherent structure based on the present test data and previous data. [ABSTRACT FROM AUTHOR]

Ti-containing mesoporous silica was prepared and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectrometry (UV-Vis) and the N2 adsorption technique. The adsorption behaviours of Cr(iii), Cu(ii), Cd(ii) and Pb(ii) on Ti-containing mesoporous silica were studied and the adsorption mechanism was also investigated by FT-IR and X-ray photoelectron spectroscopy (XPS). With Ti-containing mesoporous silica as the adsorbent, a new method of microcolumn solid phase extraction (SPE) combined with inductively coupled plasma-mass spectrometry (ICP-MS) was established for the determination of Cr(iii), Cu(ii), Cd(ii) and Pb(ii) in environmental samples. The parameters affecting extraction and desorption of the target analytes, such as pH, sample flow rate, desorption reagent, desorption flow rate and sample volume, were investigated. Under optimized conditions, the limits of detection (LODs) of Cr(iii), Cu(ii), Cd(ii) and Pb(ii) were 19, 39, 7 and 13 pg mL−1 with a preconcentration factor of 10, respectively, and the relative standard deviations (RSDs) varied from 6.1 to 7.3% (n = 7, c = 1 ng mL−1). The developed method was applied to analyze environmental water and soil samples with recovery in the range of 85–119% for the spiked samples. In order to validate the accuracy of the method, certified reference materials of GSBZ50009-88 (environmental water), GBW07429 and GBW07425 (soil sample) were analyzed and the determined values were in good agreement with the certified values. The developed method is simple, rapid, sensitive and suitable for the analysis of trace elements in environmental samples with complex matrices. [ABSTRACT FROM AUTHOR]

Nitroxide (NO) spin radicals are effective in characterizing structures, interactions and dynamics of biomolecules. The EPR applications in cell lysates or intracellular milieu require stable spin labels, but NO radicals are unstable in such conditions. We showed that the destabilization of NO radicals in cell lysates or even in cells is caused by NADPH/NADH related enzymes, but not by the commonly believed reducing reagents such as GSH. Maleimide stabilizes the NO radicals in the cell lysates by consumption of the NADPH/NADH that are essential for the enzymes involved in destabilizing NO radicals, instead of serving as the solo thiol scavenger. The maleimide treatment retains the crowding properties of the intracellular components and allows to perform long‐time EPR measurements of NO labeled biomolecules close to the intracellular conditions. The strategy of maleimide treatment on cell lysates for the EPR applications has been demonstrated on double electron‐electron resonance (DEER) measurements on a number of NO labeled protein samples. The method opens a broad application range for the NO labeled biomolecules by EPR in conditions that resemble the intracellular milieu. [ABSTRACT FROM AUTHOR]

Abstract: A flume experiment was conducted to investigate the effect of the aquatic herbaceous plant patch on the turbulent structure and flow field of shallow water. The eel grass that is widely distributed in the shallow lakes in China was chosen as the targeted plant. The plants were settled in patch form with three groups of densities and flow velocities. The three-dimensional instantaneous velocities were measured using an Audio Doppler Velocitimeter (ADV). The results indicate that the vertical velocity profile in the plant patch exhibits an S-shape from the canopy to the root of the eel grass. A secondary maximum in the vertical profile of velocity near the plant root is observed. The turbulent intensity increases from the water surface to the canopy, then decreases to the plant root; there is an inflection point around canopy, where the turbulent intensity deceases from the inner region to the side boundary of the patch. The vertical profiles of the eel grass resistance coefficient C P have different forms at different positions in the patch in general, but the forms of the C P profiles are similar along the boundary of the patch, and the forms of the C P profiles are similar in the inner part of the patch. In the patch area, the turbulent flow corresponds to the Quadrant 2 event (ejection event) above the canopy, the turbulent flow corresponds to the Quadrant 4 event (sweep event) below the canopy, but near the bed the Quadrant 1 event (outward interaction), the Quadrant 2 event and the Quadrant 4 event coexist. In the lateral boundary area of the patch the Quadrant 2 event and the Quadrant 3 event (inward interaction event) coexist due to presence of a strong shear layer. [Copyright &y& Elsevier]

A new small strain multi-directional forging (MDF) with gradient cooling was proposed to tailor the microstructure and improve the mechanical properties of Mg alloys. Using MDF with a cumulative strain of 2.7, a uniform fine-grained microstructure with an uncommon bimodal basal texture was achieved. Influenced by the Schmid factor, the twins in the< 10–10 > type grains rotated the basal poles toward the last forging direction (LFD), whereas the twins in the< 11–20 > type grains refined the microstructure. The dominant refinement mechanisms at high temperatures were twinning segmentation (TS) and discontinuous dynamic recrystallization (DDRX). It gradually became continuous dynamic recrystallization (CDRX) as the temperature was lowered. Twinning-induced recrystallization (TDRX) also occurred at 200 ℃. The plastic deformation and DRX mechanism affected the texture evolution of the grains. With a cumulative strain of less than 0.3, {10–12} twinning was dominant and responsible for the formation of the< 0001 > //LFD texture. As the cumulative strain increased to 0.9, multiple slips began to dominate the deformation, and a relatively stable< 10–12 > –< 11–24 > //LFD bimodal basal texture was formed. In contrast, the DRXs had little effect on texture types. The yield strengths were affected by the grain sizes and textures during MDF. The fluctuations of strength in the initial stage were mainly attributed to the texture change. When the texture was stabilized, the increases in strength were owing to grain refinement. The yield strengths can be accurately estimated by an improved Hall-Petch relation that includes the texture effect. • A newly small strain multi-directional forging with gradual cooling was proposed. • Fine-grained microstructure achieved undergoing sequential TS, DDRX, CDRX and TDRX. • Uncommon bimodal basal texture attributed to multiple slips activated by the MDF path. • Yield strengths and the anisotropy well estimated by an improved Hall-Petch relation. [ABSTRACT FROM AUTHOR]

A novel restricted accessed material (RAM)—Cu(II) ion imprinted polymer (IIP) was synthesized by the surface imprinted-emulsion method, and possessed a high selectivity to Cu(II) and good macromolecules exclusion property. And a novel method of RAM-IIP packed microcolumn solid phase extraction (SPE) combined with inductively coupled plasma-optical emission spectrometry (ICP-OES) was developed for the determination of trace free Cu(II) in human body fluids. Under the optimized conditions, the adsorption capacity of RAM-IIP for Cu(II) was 15.9mgg−1. With a preconcentration factor of 30, the limit of detection was 0.17µgL−1, and the relative standard deviation was 2.2% (n=7, c=1µgL−1). The developed method was validated by the analysis of two Certified Reference Materials, and the determined values were in good agreement with the certified values. This method was also successfully applied for the direct analysis of free Cu(II) in human urine and serum samples. While the total Cu can be determined by the proposed method after microwave digestion. The concentrations of free Cu(II) were much lower than that of total Cu, indicating that Cu is mainly coordinated with macromolecules in these biological samples. From this point of view, the developed method exhibits application potential in speciation of free metal ions and metallic complex molecules in biological samples. [ABSTRACT FROM AUTHOR]

Abstract: The increasing use of zebrafish larvae for biomedical research applications is resulting in versatile models for a variety of human diseases. These models exploit the optical transparency of zebrafish larvae and the availability of a large genetic tool box. Here we present detailed protocols for the robotic injection of zebrafish embryos at very high accuracy with a speed of up to 2000 embryos per hour. These protocols are benchmarked for several applications: (1) the injection of DNA for obtaining transgenic animals, (2) the injection of antisense morpholinos that can be used for gene knock-down, (3) the injection of microbes for studying infectious disease, and (4) the injection of human cancer cells as a model for tumor progression. We show examples of how the injected embryos can be screened at high-throughput level using fluorescence analysis. Our methods open up new avenues for the use of zebrafish larvae for large compound screens in the search for new medicines. [Copyright &y& Elsevier]

Ionic liquids of methyltrioctylammonium chloride modified magnetic nanoparticles were prepared, and a new method of magnetic solid phase extraction combined with inductively coupled plasma-optical emission spectrometry was established for the determination of Cu, Zn, and Cd in human hair and urine samples. The effect of pH on the extraction of Cu, Zn, and Cd was investigated. The results show that the ionic liquid played a key role in the extraction of target analytes. The magnetic nanoparticles served as the carriers of the ionic liquid and the base of the phase separation. Several parameters affecting the extraction and desorption of the target analytes were investigated including the sample volume, extraction time, eluent concentration and volume, desorption time, sedimentation time, amount of the ionic liquid and Fe3O4@Si–OH, and the optimized conditions were established. Under the optimized conditions, the detection limits of Cu, Zn, and Cd were 0.54, 0.56, and 0.33 μg L−1, respectively, and the relative standard deviations (n = 7) were 4.9% (c = 2 μg L−1), 3.7% (c = 2 μg L−1), and 5.1% (c = 1 μg L−1), respectively. To validate the accuracy of the proposed method, it was applied to analyze certified reference materials of GBW07601 human hair and GBW09103 human urine. The determined values agree with the certified values. The developed method was also employed to analyze human hair and urine, and the recoveries for the spiked samples were in the range of 89.1% to 120%. The developed method was simple, highly sensitive, solvent-free, chelate-free, and could be considered as a green analytical technique. [ABSTRACT FROM AUTHOR]

Abstract: A novel alumina hollow fiber was synthesized by sol–gel template method and was characterized by scanning electron microscopy, N2 adsorption technique and X-ray diffraction. With the use of prepared alumina hollow fiber as extraction membrane, a new method of flow injection (FI)-membrane solid phase microextraction (MSPME) on-line coupled to inductively coupled plasma-optical emission spectrometry (ICP-OES) was developed for simultaneous determination of trace metals (Cu, Mn and Ni) in environmental water samples. The adsorption capacities of the alumina hollow fiber for Cu, Mn and Ni were found to be 6.6, 8.7 and 13.3mgg−1, respectively. With a preconcentration factor of 10, the limits of detection (LODs) for Cu, Mn and Ni were found to be 0.88, 0.61 and 0.38ngmL−1, respectively, and the relative standard deviations (RSDs) were ranging from 6.2 to 7.9% (n =7, c =10ngmL−1). To validate the accuracy, the proposed method was applied to the analysis of certified reference material GSBZ50009-88 environmental water and the determined values are in good agreement with the certified values. The developed method was also employed for the analysis of Yangtze River water and East Lake water, and the recoveries for the spiked samples were in the range of 87.4–110.2%. [Copyright &y& Elsevier]

Abstract: Polypyrrole/vanadium oxide nanotubes (PPy/VOx-NTs) as a new high-performance cathode material for rechargeable lithium-ion batteries are synthesized by a combination of hydrothermal treatment and cationic exchange technique. The morphologies and structures of the as-prepared samples are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry and differential scanning calorimeter (TG–DSC) and X-ray powder diffraction (XRD). The results indicate that the organic templates are mainly substituted by the conducting polymer polypyrrole without destroying the previous nanotube structure. Their electrochemical properties are evaluated via galvanostatic charge/discharge cycling, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It is found that PPy/VOx-NTs exhibit high discharge capacity and excellent cycling performance at different current densities compared to vanadium oxide nanotubes (VOx-NTs). After 20 cycles, the reversible capacity of PPy/VOx-NTs (159.5mAhg−1) at the current density of 80mAg−1 is about four times of magnitude higher than that of VOx-NTs (37.5mAhg−1). The improved electrochemical performance could be attributed to the enhanced electronic conductivity and the improved structural flexibility resulted from the incorporation of the conducting polymer polypyrrole. [Copyright &y& Elsevier]

Abstract: A new kind of cathode materials for rechargeable lithium-ion batteries, lithium vanadium oxide nanotubes synthesized by a combined sol–gel reaction and hydrothermal treatment procedure is reported in this paper. SEM, TEM, XRD and XPS techniques were performed to investigate the morphology and structure of the resulting materials. The results confirmed that the synthetic materials are composed of uniformly open-ended multiwalled nanotubes with a length from 1 to 3μm. The inner and the outer diameters of the obtained nanotubes vary from 30 to 50nm and 50 to 120nm, respectively. The electrochemical performance as a cathode material was examined and evaluated by cyclic voltammetry, galvanostatic charge–discharge cycling and AC impedance spectroscopy techniques. The results indicated that the resultant lithium vanadium oxide nanotubes have a high initial discharge capacity of 457mAhg−1 in the potential range of 1.0–4.0V (vs. Li/Li+) and good cycling performance. The improved electrochemical performance of the products should be due to its special one-dimensional multiwalled tubular structure and the contribution of lithium-ions. [Copyright &y& Elsevier]

It is vital to measure combustion temperature to define combustion models accurately. For single fuel particles in powder-fueled ramjets, their size distribution ranges from submicron to submillimeter, and their burn time is short to millisecond order. Moreover, the radiation intensity of different types of fuel particles significantly oscillated with several orders of magnitude. Current temperature measurement technology is facing this challenge. This paper proposes a highly spatiotemporal resolved pyrometry to measure the combustion temperature of fuel particles by coupling single-point photomultiplier tube (PMT)-based and two-dimensional complementary metal oxide semiconductor (CMOS)-based photoelectric devices. Both the offline calibration by blackbody furnace and online calibration by standard lamp confirmed the measurement accuracy of the pyrometry. Then, the pyrometry was used to measure the combustion temperature of fuel particles including micro-Al, nano-Al, micro-Mg, nano-B, and micro-B4C. The temperature evolution and distribution of burning fuel particles were complementarily obtained, especially the interfacial flame temperature near the particle surface. Based on the obtained combustion temperature, the combustion characteristics and the energy release efficiencies among these fuels were evaluated and compared in detail, which are helpful to recognize, in depth, the combustion behavior and reveal the combustion mechanism of fuel particles in powder-fueled ramjets. [ABSTRACT FROM AUTHOR]

Freshwater fungi consist of a highly diverse group of organisms in freshwater habitats worldwide. During a survey of fungal diversity in freshwater habitats across different regions of Jiangxi Province, China, four freshwater fungi were collected. To study their phylogenetic relationships, the internal transcribed spacer (ITS1-5.8S-ITS2), large subunit (28S, LSU), small subunit (18S, SSU), and RNA polymerase II subunit (RPB2) genes were selected for phylogenetic analyses. Based on morphology coupled with phylogenetic analysis, these strains were confirmed to belong to Phaeoisaria, Pleurothecium, and Pseudodactylaria. Among them, three fungi were confirmed as the new species, namely, Pleurothecium lignicola (Pleurotheciaceae), Pseudodactylaria jiangxiensis (Pseudodactylariaceae), and Ps. lignicola (Pseudodactylariaceae). One species was identified as Phaeoisaria filiformis (Pleurotheciaceae), a new record of this species in China. All species were compared with other similar species, and detailed descriptions, illustrations, and phylogenetic data were provided. [ABSTRACT FROM AUTHOR]

• Deformation mechanisms were predicted accurately by VPSC polycrystal model. • The activation of twin variants was mainly dependent on their own Schmid factor. • CDRX had little tailor role in deformation basal texture at 250 ℃. • DDRX and higher activation of pyramidalslip weakened the basal texture at 350 ℃. A series of uniaxial compression experiments were carried out on the as-extruded AZ31 Mg alloy with<10–10>-<11–20>//ED (extrusion direction) double fiber texture at 200–350 ℃. The microstructure evolution during the work hardening and dynamic softening stages were systematically investigated based on deformation mechanisms and dynamic recrystallization (DRX), respectively. Experimental and simulation results demonstrated that in the work hardening stage, the dominant deformation mechanisms were the basalslip and {10−12} twinning at 250 ℃, while the basalslip and prismaticslip 350 ℃. The appearance of profuse {10−12} twins at 250 ℃ not only effectively refined the microstructure but also quickly promoted the formation of strong<0001>//CD (compression direction) texture. Moreover, the activation of twin variants was mainly dependent on their own Schmid factor that was higher in<10–10>//CD grains, resulting in the earlier disappearance of the<10–10>//ED texture component than the<11–20>//ED texture component. In contrast, owing to the limited of {10−12} twins, the samples at 350 ℃ exhibited a weak fiber texture with diffusely distributed of basal plane along the CD. In the dynamic softening stage, high temperature increased both the grain size and proportion of DRXed grains, resulting in a more homogeneous microstructure. More importantly, the continuous DRX (CDRX) transformed into discontinuous DRX (DDRX) as the temperature increased from 250 °C to 350 °C. The similar orientation between the new CDRXed grains and parent grains at 250 ℃ preserved the strong<0001>//CD texture, while at 350 ℃ the basal texture was significantly weakened due to the random orientation DDRXed grains and higher activation of pyramidalslip. These findings are beneficial for the optimization of the temperature range of the MDF process. [ABSTRACT FROM AUTHOR]

A piezoelectric field promotes the photocatalytic activity of a photocatalyst by helping separating photo-generated charge carriers. Wurtzite phase ZnO is a typical photocatalyst with a piezoelectric property, thus self-assisted photocatalysis with ZnO based on the piezophototronic effect can be achieved. ZnO nanorods or nanowires with a clear c-axis have been well studied, while other morphologies have not been fully discussed. In this work, we prepared wurtzite phase ZnO with four different morphologies. By comparing their photocatalytic activity for degradation of Rhodamine B under the same mechanical energy source provided by ultrasound, the effect of morphology and exposed facets on photo-induced charge separation were highlighted. The ZnO nanowire photocatalyst delivered an impressive improvement in photocatalytic efficiency when ultrasound driven, suggesting that the morphology-related piezophototronic effect had a positive effect on separation of photo-generated charge carriers, and more exposed active facets benefitted the utilization of charge carriers. [ABSTRACT FROM AUTHOR]

In the application of wireless power transfer system, parameter drift of resonant tank is a general situation which induces natural frequency of primary side or secondary side deviates from switching frequency. This frequency deviation phenomenon will deteriorate load-independent constant current characteristics and decrease output power capacity for an S/S compensation system. This article illustrates the problems caused by frequency deviation through output characteristic analysis and addresses them by a self-tuning method based on switched capacitors (SCs). The proposed self-tuning method requires no resonant parameters such as compensation capacitance and coil self-inductance in advance. Primary and secondary natural frequencies can be both tuned to switching frequency continuously by SCs. The proposed method is verified by a simulation and a 500 W S/S compensation experimental prototype. After completion of self-tuning process, load-independent constant current characteristic is recovered and the output power capacity is boosted, which are in consistent with the theoretical analysis of system output characteristics. The proposed method is also applicable to LCC/S and LCC/LCC topologies. [ABSTRACT FROM AUTHOR]

• We reported 10 (3.0 %) tet (X5)- and tet (X6)-positive MDR A. baumannii isolates from sick animals. • Both the tet (X5)- and tet (X6)-positive A. baumannii strains could inactivate tetracyclines by hydroxylation. • The plasmid-borne tet (X5) and chromosomal tet (X6) genes shared homologous genetic structures with those of clinical strains. • A clonal spread of ST355 A. baumannii strains as well as IS CR2 -mediated transposition for tet (X) genes was discovered. The recent emergence of plasmid-mediated tigecycline resistance gene tet (X) has challenged the clinical effectiveness of tigecycline as a last-resort treatment option. During 2017–2018, 336 fecal samples from sick ducks, pigs, chickens and geese in Guangdong, China, were screened for tet (X)-positive Acinetobacter baumannii strains. Their activities on tetracyclines were determined by microbiological degradation and mass spectrometry, followed by susceptibility testing, sequence typing, gene transfer, molecular location and genomic DNA sequencing analyses. A total of 10 tet (X)-positive A. baumannii strains were isolated from ducks and chickens, including eight plasmid-borne tet (X5)-positive and two chromosomal tet (X6)-positive isolates. All of them exhibited good degradation activities on tetracyclines by hydroxylation at C11a and were multidrug-resistant to tigecycline, tetracycline, florfenicol, ciprofloxacin and trimethoprim/sulfamethoxazole. Genetically, they belonged to two sequence types (ST355, n = 8; ST1980, n = 2) that were consistent with their pulsotypes, revealing a clonal spread of ST355 A. baumannii. An IS CR2 - or IS 26 -mediated tet (X) transposition structure, homologous to those of clinical A. baumannii strains, was also identified and IS CR2 could transfer tet (X5) into the recipient Acinetobacter baylyi ADP1 at a frequency of (1.8 ± 0.3)×10−6. Therefore, more efforts are needed to evaluate the clinical impact of these tigecycline resistance genes. [ABSTRACT FROM AUTHOR]

Coal macrolithotypes control the reservoir heterogeneity, which plays a significant role in the exploration and development of coalbed methane. Traditional methods for coal macrolithotype evaluation often rely on core observation, but these techniques are non-economical and insufficient. The geophysical logging data are easily available for coalbed methane exploration; thus, it is necessary to find a relationship between core observation results and wireline logging data, and then to provide a new method to quantify coal macrolithotypes of a whole coal seam. In this study, we propose a L-Index model by combing the multiple geophysical logging data with principal component analysis, and we use the L-Index model to quantitatively evaluate the vertical and regional distributions of the macrolithotypes of No. 3 coal seam in Zhengzhuang field, southern Qinshui basin. Moreover, we also proposed a S-Index model to quantitatively evaluate the general brightness of a whole coal seam: the increase of the S-Index from 1 to 3.7, indicates decreasing brightness, i.e., from bright coal to dull coal. Finally, we discussed the relationship between S-Index and the hydro-fracturing effect. It was found that the coal seam with low S-Index values can easily form long extending fractures during hydraulic fracturing. Therefore, the lower S-Index values indicate much more favorable gas production potential in the Zhengzhuang field. This study provides a new methodology to evaluate coal macrolithotypes by using geophysical logging data. [ABSTRACT FROM AUTHOR]