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s Atherosclerosis is a chronic multifactorial cardiovascular disease. A Western diet has been reported to affect atherosclerosis through regulation of adipose function. In high cholesterol diet-fed ApoE–/– mice, adipocyte HIF-1α deficiency or direct HIF-1α inhibition by the selective pharmacological HIF-1α inhibitor PX-478 alleviates high cholesterol diet-induced atherosclerosis by reducing adipose ceramide generation, which lowers cholesterol levels and reduces inflammatory responses, resulting in improved dyslipidemia and atherogenesis. Smpd3, the gene encoding neutral sphingomyelinase, is identified as a new target gene directly regulated by HIF-1α that is involved in ceramide generation. Epididymal adipose tissue injected with lentivirus-SMPD3 reverses the decrease in ceramides in adipocytes and eliminates the improvements on atherosclerosis in the adipocyte HIF-1α-deficient mice. Therefore, inhibitors of HIF-1α may constitute a novel approach to slow atherosclerotic progression.

Leaf wetness duration (LWD) provides the necessary conditions for pathogen infection. Among them, dew condensation on the crop canopy due to high humidity in a greenhouse is a major cause of LWD formation. However, it would be costly to monitor the condensation of all the leaves in a greenhouse. A computational fluid dynamics model was studied for the spatial and temporal distribution of the indoor microclimate and leaf condensation in a single-slope Chinese solar greenhouse at night. Models were embedded to simplify the input parameters and enhance the practicality. Without compromising the performance of the model, the model inputs were reduced to five: outdoor solar radiation intensity, outdoor air temperature, outdoor relative humidity, outdoor average wind speed per hour, and soil temperature. The distributions of roof condensation and leaf condensation were simulated. Condensation always appeared first on the roof rather than on the leaves. The leaf condensation results were manually observed for comparison with the simulated results. Leaf condensation always occurred first in the area near the semi-transparent roof, both in the observations and the simulation. The LWD was simulated by considering the duration of the simulated leaf condensation at each point. The evaluation was conducted on 216 pairs of samples. The True Negative Rate (TNR), True Positive Rate (TPR), and Accuracy (ACC) were 1, 0.66, and 0.89, respectively. This paper can serve as a reference for an early warning model of disease based on the temporal and spatial distribution of leaf condensation.

Positioned within intercultural pragmatics, particularly the salience theory of the Socio-cognitive Approach (SCA) proposed and developed by Kecskes (2008, 2013, 2017, and 2019), this article explores the role of metapragmatic expressions (MPEs) in salience adjusting in complaint responses in the context of intercultural phone interactions. Drawing on data from 42 recordings of English phone interactions between English speaking customers and Chinese agents of a complaint center of one Chinese airline, MPEs used in the interactions are analyzed to address two research questions: 1) What types of MPEs are used by the agents and customers in complaint responses? 2) How are these MPEs used to adjust salience in complaint responses to facilitate complaint settlement? Data analysis reveals that, faced with institutional, linguistic, and sociocultural constraints, the speakers mainly employ five types of MPEs to adjust the emergent situational salience of relevant information or knowledge, including business rules and regulations, language use, social-cultural knowledge, and emotional states. In salience adjusting, the agents tend to be information-oriented and institutionalized whereas the customers tend to be both emotion- and information-oriented, but highly personalized. The findings shed light on intercultural pragmatics and customer service training in business communication.

The n-butanol as a clear and renewable biofuel is considered an ideal alternative fuel for SI engines. Hydrogen as a partial alternative fuel can improve the combustion and emissions of SI engine because of its advantages of low ignition energy, fast flame propagation and so no. In order to decrease the additional NOx caused by hydrogen addition, the cooperative effect of EGR and hydrogen direct injection on combustion and emission in an SI n-butanol engine was investigated in this paper. Experiments are conducted at five hydrogen addition ratios (0%, 5%, 10%, 15%, 20%), five EGR ratios (0%, 5%, 10%, 15%, 20%) and three excess air ratios (1, 1.1, 1.2) with 1500 rpm of engine speed. The results indicate that Ttq, Pmax, dQmax and Tmax decrease with the increasing η EGR and increase with the increasing φ H 2 , while the APmax, AdQmax, θ0–10 and θ10–90 show the contrary tendency. The 15% EGR rate cooperate with 10%~15% hydrogen addition ratio can keep emissions (HC, CO, NOx) better than the original engine. Compared to the original pure butanol engine, the n-butanol engine with hydrogen direct injection and EGR could obtain better comprehensive performance through the coordinated control of φ H 2 and η EGR . More specifically, 15% EGR rate cooperated with 10% hydrogen addition ratio can obtain better comprehensive performance of combustion and emission, but there is a little expense on combustion parameters compared to the original engine under λ = 1. So the 15% EGR ratio is considered a superior EGR ratio cooperated with hydrogen addition.

BiFeO3(BFO)/Sr2Bi4Ti5O18(SBT) bilayer composite thin films were prepared using the sol-gel method. The influence of the SBT transition layer thickness on the properties of BFO/SBT bilayer composite thin films was studied. The results showed that an SBT transition layer with the proper thickness can improve the BFO/SBT bilayer composite film performance. X-ray diffraction (XRD) analysis revealed that a bismuth layered perovskite structure is formed in all of the thin films. The scanning electron microscopy (SEM) result showed that the BFO/80 nmSBT sample exhibits good crystallization, an improved density and a uniform minimum grain size compared with the other samples. The X-ray photoelectron spectroscopy (XPS) result showed that the Fe2+ content and oxygen vacancy concentration are lowest in the BFO/80 nm SBT sample. This sample has good ferroelectric properties: the leakage current density has the lowest value of J = 5.21 × 10-5 A/cm2 among the samples at 350 kV/cm, 2Ec = 900 kV/cm, and 2Pr = 151 μC/cm2. At a low electric field (E 100 kV/cm). The relative dielectric constant (er) is 121, the dielectric loss (tanδ) is 0.024 at 105 Hz.

Detection of ammonia (NH3) concentration plays an important role in monitoring and controlling air pollutants. However, the existing NH3 detection methods do not conform to current needs. A low-cost and easily-realized gas sensing system for NH3 detection is developed using two near-infrared (NIR) liquid quantum dot light emitting diodes (QD-LEDs), a single photoelectric detector and time-division multiplexing (TDM) technique. The liquid-type NIR QD-LEDs are fabricated by a combination of PbSe QD solution with blue GaN LEDs. A long path gas cell is designed and adopted for realizing and enhancing gas detection. Detailed measurements are carried out to study the performance of the sensor system. The results show that the detection limit of the system is 10ppm, and the corresponding measurement relative error of 4 h continuous monitoring is less than 2%. The proposed sensor has potential applications in various fields requiring NH3 detection such as in atmospheric quality assessment, industrial products processing, medical diagnosis, and so on.

The Sr2Bi4Ti5O18 (SBT-5) ferroelectric thin films were prepared on Pt/Ti/SiO2/Si substrate using the sol-gel method and annealing in oxygen, air, and nitrogen. Their properties were measured. After annealing in oxygen, the films showed good crystallization and a larger average grain size of approximately 34.05 nm. XPS analysis clearly showed that annealing in oxygen inhibited the generation of oxygen vacancies in the films, which contributed to the melioration of the ferroelectric properties. The remanent polarization was 20.09 μC/cm2 and the coercive field was 75 kV/cm. When the electric field was 15 kV/cm, the leakage current density was approximately 3.88 × 10−7A/cm2, while the Ohmic conduction was the dominating leakage mechanism. Because the content of the oxygen vacancy in the samples annealed in oxygen atmosphere was lower, the fixing effect on the domain structure was weaker and the volume effect was not obvious, so the aging degree of the samples was low. The larger relative dielectric constant was 742, while the dielectric loss was 0.037 when the test frequency was 2.0 × 105 Hz.

Ultrasound-responsive chemistry was exploited in manufacture of drug delivery nanoparticulates for pursuit of on-demand ultrasound-stimulated drug release function. In principle, the ultrasound-labile oxyl-alkylhydroxylamine (-oa-) linkage was tailored between the segments of amphiphiles. Consequently, the hydrophobic chemotherapeutic doxorubicin could be readily assembled with the hydrophobic segments of amphiphiles into interior compartments, whereas the hydrophilic segments represented as the external surroundings. Upon ultrasonication, the proposed phase-segregated self-assemblies were determined to be subjected to evident structural rearrangement as a consequence of -oa- cleavage. Simultaneously, the release rate of doxorubicin payloads appeared to accelerate due to the ultrasound-induced structural destabilization, consequently eliciting potent cytotoxic efficacy at the affected cells. Another noteworthy characteristic of the proposed self-assemblies was poly (lactobionamidoethyl methacrylate) (pLAMA) as the hydrophilic components of the amphiphiles, characterized to possess galactosylated residues. In view of the specific affinity of galactosylated residues (and lactosylated residues) to asialoglycoprotein receptors (overexpressed on the surface of intractable hepatocellular carcinoma), the proposed self-assemblies were determined to impart preferential affinities to hepatocellular carcinoma. Together with the strategic ultrasound-stimulated drug release property, our proposed drug delivery system demonstrated appreciably pharmaceutical efficacy on hepatocellular carcinoma.

The level set model is a popular method for object segmentation. However, most existing level set models perform poorly in color images since they only use grayscale intensity information to defined their energy functions. To address this shortcoming, in this paper, we propose a new saliency-guided level set model (SLSM), which can automatically segment objects in color images guided by visual saliency. Specifically, we first define a global saliency-guided energy term to extract the color objects approximately. Then, by integrating information from different color channels, we define a novel local multichannel based energy term to extract the color objects in detail. In addition, unlike using a length regularization term in the conventional level set models, we achieve segmentation smoothness by incorporating our SLSM into a graph cuts formulation. More importantly, the proposed SLSM is automatically initialized by saliency detection. Finally, the evaluation on public benchmark databases and our collected database demonstrates that the new SLSM consistently outperforms many state-of-the-art level set models and saliency detecting methods in accuracy and robustness.

In Liu and Liu (2017), we argued that business English as a lingua franca (BELF) speakers lack common ground (CG) and core CG and explored the role of metapragmatic expressions (MPEs) in creating emergent CG in BELF meetings. Zhang and Wu commented on our article in this volume, arguing that BELF speakers share adequate CG, and MPEs are used as the overall discursive strategy rather than as linguistic devices to create emergent CG. In this response, we argue that CG sharing in communication is an issue of ‘more-or-less.’ Compared with participants in intracultural communication, BELF speakers do lack (core) CG. Being aware of potential or existing problems in communication, BELF speakers employ MPEs as emergent CG-creating devices to activate shared sense and current sense to facilitate ongoing interactions.

Acute lung injury (ALI), a persistent lung inflammatory response syndrome, may evolve into acute respiratory distress syndrome (ARDS). Characterized by rapid onset, critical features, and a complex etiology, ALI remains a challenging critical respiratory disease. Recently, mesenchymal stem cells (MSCs) have provided a new solution for the treatment of ALI. We built a lipopolysaccharide (LPS)-induced ALI model in mice. After treatment with human umbilical cord mesenchymal stem cells (hUC-MSCs), FTY720, or a combination of hUC-MSCs and FTY207, the lung inflammatory response was apparently attenuated. To understand the mechanism underlying MSCs treatment of ALI at the genetic level, significant differentially expressed long non-coding RNAs (lncRNAs) between the treatment and model groups were analyzed using microarray technology. Moreover, genetic gene prediction, gene ontology (GO) analysis, pathway analysis, and transcription factor (TF) prediction were carried out. The results showed that a total of 66 lncRNAs were differentially expressed in all three treatment groups, including 8 up-regulated and 58 down-regulated lncRNAs. LncRNA A_30_P01029806 and A_30_P01029194, which were down-regulated, were involved in the signaling pathways closely related to ALI. Through further TF analysis, we identified several significant TFs which lay a foundation for revealing the mechanism underlying lncRNAs treatment of ALI. LncRNA A_30_P01029806 and A_30_P01029194 may serve as candidate biomarkers in the diagnosis and treatment of ALI.

Klebsiella pneumoniae is one of the major Gram-negative bacterial pathogens causing hospital-acquired multidrug-resistant infections, and the antimicrobial treatment options are scarce. The lack of available antimicrobials has prompted the development of alternative strategies for the treatment of these infections. In this study, a K. pneumoniae bacteriophage (vB_KpnP_IME321) targeting a KN1 capsular type strain, Kp409, was isolated, characterized and sequenced. This bacteriophage has a latent period of 20 min and a burst size of approximately 410 pfu/cell. It contained 49 predicted open reading frames, of which ORF42 was identified as encoding the putative capsule depolymerase. The enzyme expressed and purified in the Escherichia coli BL21 system, namely Dp42, could depolymerize the capsular polysaccharide of Kp409 and form translucent halos on the plates. The phage-encoded depolymerase could increase the inhibitory effect of serum on the growth of bacteria in vitro. Pre-treated with Dp42 rescued 100% of mice following lethal Kp409 challenge, and administration of this enzyme after infection significantly increased survival rates of infected mice in the animal experiment. In conclusion, the phage-encoded depolymerase Dp42 represents a potential alternative strategy for controlling infections mediated by K. pneumoniae expressing the KN1 capsular polysaccharide.

Fuel cell hybrid excavators (FCHEs) are an attractive long-term future option. This paper presents an approach for the energy management and economic analysis for an excavator powered by fuel cell and supercapacitor. The operating conditions and energy flows of a hydraulic excavator are analysed, the influence factors of the fuel cell stack (FCS) lifetime under the operating conditions are discussed. The marked load changes posed major challenges to the FCS performance, appropriate energy management strategies (EMSs) for FCHEs are indispensable. Three representative EMSs based on dynamic programming, Pontryagin's minimum principle, and model predictive control are developed, considering hydrogen consumption and FCS durability. Simulations performed in the MATLAB environment with cyclic loading of an excavator demonstrate the superiority of the proposed EMSs. With the introduction of restrictions on FCS power change, FCS durability can be improved. Economic analysis of the FCHE is proposed, which includes the effect of FCS and supercapacitor sizes on hydrogen consumption, and the use-cost at the present and in the future. It indicates that the sizes of FCS are the primary influence on the FCHE fuel economy. FCHEs will become increasingly attractive as costs fall.

This study investigated how Ca doping affects the electrical properties of Sr 2 Bi 4 Ti 5 O 18 (SBT) ceramics. Among the samples tested, a sample with a substitution level of 0.15 showed the highest a -axis orientation and the largest lattice distortion. Through XPS analysis, it was found that the formation of oxygen vacancies is suppressed by Ca substitution in SBT. A large remnant polarization (2 Pr ) of 17.7 μC/cm 2 and small coercive field (2 Ec ) of 91 kV/cm was observed for the Ca 0.15 Sr 1.85 Bi 4 Ti 5 O 18 (CSBT-0.15) ceramic, which indicated that this sample possessed the best ferroelectric properties. As the substitution level increased, the variation of the leakage current density first decreased and then increased, and the sample with the substitution level of 0.15 showed the smallest leakage current density of J = 1.1 × 10 −6 A/cm 2 at ~80 kV/cm. For the investigated Ca x Sr 2-x Bi 4 Ti 5 O 18 (CSBT) ceramic samples, space-charge-limited conduction (SCLC) was determined to be the main conduction mechanism.

Pyrimidines are critical nutrients and key biomolecules in nucleic acid biosynthesis and carbohydrate and lipid metabolism. Here, we proposed the concept of the pyrimidine metabolome, which covers 14 analytes in pyrimidine de novo and salvage synthetic pathways, and established a novel analytical strategy with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to efficiently illustrate pyrimidine transient distribution and dynamic balance. The lower limits of quantification (LLOQs) of all analytes were less than 10 ng/mL. Acceptable inter- and intra-day relative deviation (15%) was detected, and good stability was obtained under different storage conditions. Metabolomics analysis revealed pyrimidine metabolic diversity in the plasma and brain among species, and a visualization strategy exhibited that pyrimidine biosynthetic metabolism is quite active in brain. Distinct metabolic features were also observed in cells with pyrimidine metabolomic disorders during proliferation and apoptosis. Absolute concentrations of pyrimidine metabolites in different bio-samples offered reference data for future pyrimidine studies.

The active contour model is a widely used method for image segmentation. Most existing active contour models yield poor performance when applied to images with severe intensity inhomogeneity. To address this issue, we propose an adaptive-scale active contour model (ASACM) based on image entropy and semi-naive Bayesian classifier, which achieves simultaneous segmentation and bias field estimation for images with severe intensity inhomogeneity. Firstly, an adaptive scale operator is constructed to adaptively adjust the scale of the ASACM according to the degree of the intensity inhomogeneity. Secondly, we define an improved bias field estimation term via distributing a dependent-membership function for each pixel to estimate the bias field in severe inhomogeneous images. Thirdly, a new penalty term is proposed using piecewise polynomial, which helps to avoid time-consuming re-initialization process and instability in conventional penalty term. The experimental results demonstrate that the proposed ASACM consistently outperforms many state-of-the-art models in segmentation accuracy, segmentation efficiency and robustness w.r.t initialization and noise.

A novel "cortex-like" micro/nano dual-scale structured TiO2 coating was prepared on a titanium surface by micro-arc oxidation (MAO) with tetraborate electrolytes. This structure, which combines microslots with nanopores, exhibits super hydrophilicity. This coating modified the surface structure, chemistry, and hydrophilicity in a one-step treatment. Evolution of the coating together with its surface and structure properties was studied. We propose a forming mechanism of the dual-scale structure in which the oxides formed during the MAO discharge dissolve in the tetraborate electrolytes, leaving little or no deposition outside the discharge channels. We performed in vitro tests using human bone marrow-derived mesenchymal stem cells (hBMSCs) that compared this coating with a "volcano-like" MAO coating and a commercial sandblasted, large-grit and acid-etched (SLA) coating. The adhesion, morphology, proliferation, and differentiation of hBMSCs, together with the matrix mineralization, were investigated. Results suggest that the "cortex-like" structure significantly promotes the adhesion, spreading, and differentiation of cells and increases the matrix mineralization. In vivo tests with mongrel dogs showed an excellent osseointegration of the "cortex-like" coating. The combination of the dual-scale structure and the hydrophilicity of the "cortex-like" TiO2 coating synergistically resulted in an outstanding cytocompatibility and osseointegration, which may facilitate a higher level of implant success.

The emergence and dissemination of carbapenem-resistant Escherichia coli (E. coli) strains is a main risk for global public health, but little is known of carbapenemase producing E. coli in Henan, China. The study was undertaken to investigate the prevalence and mechanism of carbapenem-resistant E. coli strains in a hospital in Xinxiang, Henan, China, 2014. A total of 5 carbapenemase-producing E. coli strains were screened from 1014 isolates. We found that they were all resistant to meropenem and imipenem. Amikacin showed the best sensitivity, with gentamicin coming up next. The positive rate of blaNDM was 80% (4/5). The sequencing results showed that two isolates belonged to blaNDM-1 whereas other 2 isolates carried the blaNDM-5. Other carbapenemase genes including blaIMP, blaVIM, blaKPC and blaOXA-48 were not detected. The blaCTX-M-15, blaTEM-1, sul2, aad, and aac(6”)–Ib–cr were also detected. MLST analysis showed that NDM-producing E. coli were sporadic. Conjugation test indicated blaNDM could be transferred. In conclusion, the blaNDM was the principal resistance mechanism of carbapenem-resistant E. coli in the hospital, Henan, China. Keywords: blaNDM, Carbapenem-resistant, Escherichia coli

The application of fuel cell hybrid construction equipment (FCHCE) represents an attractive option for future industrial development. Construction equipment has highly repetitive modes of operation, which can be used for predictive control. However, the loads usually change markedly and frequently, leading to adverse scenarios for energy management. In this paper, we focus on alleviating this problem by presenting a predictive energy management strategy based on a model predictive control (MPC) framework for FCHCE. The supervisory-level energy management objectives are to respond to rapid variations in the load of the construction equipment while minimizing the fuel consumption, improving fuel cell durability, and maintaining the state of charge (SoC) of supercapacitors within the allowable bounds. To improve the performance and practicality of the predictive controllers, we present two power demand prediction methodologies based on Markov chains and neural networks. Simulations are carried out on the representative driving cycles of a wheel loader. Simulation results validate the feasibility and effectiveness of the proposed MPC. Neural network model made better predictions than the Markov chain model, which is preferable when modeling comprehensive driving cycles.

Orthopedic implants need to be coated with biomedical coatings that can facilitate osseointegration and mitigate bacterial biofilm formation. Using anodisation and electrodeposition techniques, we modified Ti implants with a double-layer coating made of TiO 2 nanotubes (TNT) and hydroxyapatite that was codoped with silver and manganese (AgMnHA). The silver incorporation into hydroxyapatite improves its antimicrobial properties, and the manganese doping offsets the potential cytotoxicity of the incorporated silver. The AgMnHA and the TNT films were characterized with X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The results highlight that the manganese and silver ions were evenly incorporated into the AgMnHA/TiO 2 coating. Its adhesion strength significantly increased because of the interlocking of the rough TiO 2 layer with the bioceramic particles that entered into the voids of the TiO 2 nanotubes. The coating decreases the corrosion current density of titanium from 3.71 μA to 0.19 μA, and increases its corrosion resistance by almost two orders of magnitude. The coating can continuously release silver ions into the bacterial suspension, resulting in excellent antimicrobial efficacy with a 100% reduction in viable cells. Both hydroxyapatite and the AgMnHA/TiO 2 coating are super-hydrophilic; meanwhile, if immersed in a simulated body fluid, they could induce the deposition of typical spherical apatite. In-vitro cell culture tests demonstrated that hydroxyapatite and the AgMnHA/TiO 2 coating considerably improved the cell viability and the alkaline phosphatase (ALP) activity. Therefore, the AgMnHA coating has no significant cytotoxicity on osteoblasts, and could generate sufficient osteoblast differentiation for osseointegration. We therefore find that a bilayer AgMnHA/TiO 2 coating on Ti implants improves antibiofilm properties that does not offset the hydroxyapatite biocompatibility that is needed for successful osseointegration and bone healing.

In this paper, the TiO2 nanorod arrays (TiO2 NRAs)/PEDOT-type conducting polymers composites were prepared by a simple electrochemical polymerization method and used as materials for ultraviolet (UV) photodetectors. The poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(3,4-propylenedioxythiophene) (PProDOT) were selected as PEDOT-type conducting polymers. The structural, morphology and properties of photocurrent response of PEDOT/TiO2 NRAs and PProDOT/TiO2 NRAs were systematically studied. The results indicated that the polymer film grown on TiO2 NRAs surface presented three-dimensional porous network structure, and there was a strong interaction between polymer film and TiO2 NRAs. The results of the I–V characteristic curve showed that the composites had good rectification behavior. Due to the p-n heterojunction formed between n-type TiO2 NRAs and p-type polymer, both PEDOT/TiO2 NRAs and PProDOT/TiO2 NRAs had photocurrent response performance under 0 V and 1 V bias. Compared with the PEDOT/TiO2 NRAs, the PProDOT/TiO2 NRAs showed better UV photodetection performance, and the rise and fall time were respectively 26.2 s and 37.78 s at a bias of 1 V, while the rise and fall time were respectively 0.49 s and 8.79 s at a bias of 0 V. This research has certain potential and application value in the field of UV photodetectors.

A hybrid system including the solid oxide fuel cell (SOFC), Carnot cycle, and Brayton cycle is proposed, where the high-grade waste heat and residual fuel from the SOFC is utilized and transformed into power. Based on electrochemistry and thermodynamics, the electric power, flow rate of waste heat, and composition of residual fuel from the SOFC are calculated, respectively, under a given flow rate of natural gas into the anode of SOFC. The working substance of Carnot cycle absorbs heat in the cooling-tube of SOFC stack and the efficiency of the cycle is derived by considering the finite-rate heat transfer and internal irreversible losses. The working substance of Brayton cycle absorbs high-temperature heat from the combustion products of the residual hydrogen and the efficiency of Brayton cycle is obtained by considering the finite-rate heat transfer and irreversible compression and expansion processes. To achieve optimal power of SOFC or the maximum power of the hybrid system, the favorable working temperature, mole flow rate of natural gas, and hydrogen utilization factor in SOFC are calculated by using MATLAB software.

This paper proposes a multi-exit evacuation model based on a continuous model for the pedestrian evacuation problem. Firstly, it is determined that the distance between pedestrians and exits, the pedestrian density near exits, and the width of exits are the main factors for exit selection. A pedestrian multi-exit selection model is defined by taking the three factors into account. Secondly, a pedestrian evacuation model is constructed by considering the impact of pedestrian psychological factors on expected speed and exit attractiveness. Finally, the multi-exit evacuation is simulated, and the pedestrian evacuation process is tested on three conditions. The effects of pedestrian density near the exit and the width of exit are analyzed on the final simulation. The simulation results show that the evacuation model can effectively simulate the pedestrian evacuation process in multi-exit scenarios.

Root respiration is a critical function of root carbon cycling and accounts for a major component of the global carbon budget. However, the insufficient understanding of the global scaling relationships between root traits and respiration rate (Rr) impedes the accurate prediction of carbon effluxes from roots. Here, we analyzed a dataset of 138 species to unravel and quantify the effects of mycorrhizal type, climate, soil, and phylogenetic structure of species on fine root trait-function relationships. Four commonly measured traits were included: root nitrogen content (RNC), specific root length (SRL), root diameter, and root tissue density. We found that mycorrhizal type and climate affected the relationships between fine root traits and Rr. Specifically, the slopes of SRL-Rr and RNC-Rr relationships for ectomycorrhizal (EM) plants were significantly greater than those for arbuscular mycorrhizal (AM) plants, irrespective of the phylogenetic conservatism or plant growth forms. This finding suggested that EM plants consumed more carbon than AM plants for constructing root tissue structures. In a warmer environment, the SRL-Rr relationship was stronger while the RNC-Rr relationship was weaker, possibly because Rr was limited by enzyme activity at low temperature and by substrate supply at high temperature. Our results highlighted the importance of mycorrhizas in influencing the root trait-function relationships. Thus, incorporating mycorrhizal types into trait-based terrestrial biosphere models may help to more accurately predict the future carbon-climate change feedback.

Knowledge of root: shoot ratio (R/S) is fundamental for our understanding of carbon allocation and storage in terrestrial ecosystems. Due to the periodic variation of water table and the difficulty of measuring belowground biomass (BGB), macrophyte biomass allocation in both coastal and inland wetlands remains unclear, especially at regional scale. In this study, 131 records of biomass allocation in wetlands were collected to examine general pattern of macrophyte R/S in relation to climate, soil, and hydrological factors in China using model selection and variance decomposition analysis. Our results showed that coastal wetlands supported higher aboveground biomass (AGB, 3.1 kg m−2) but a lower R/S (1.2) than inland ones (1.47 kg m−2 and 3.1, respectively). The positive relationships between AGB and BGB and between BGB and R/S in coastal wetlands were significantly different from those in inland wetlands, while only inland wetlands exhibited a significant negative correlation between R/S and AGB (R2 = 0.19, p

Particulate matter with an aerodynamic diameter less than 2.5 μM (PM2.5) is one of the major environmental pollutants in China. In this study, we carried out a metabolomics profile study on PM2.5-induced inflammation. PM2.5 from Beijing, China, was collected and given to rats through intra-tracheal instillation in vivo. Acute pulmonary injury were observed by pulmonary function assessment and H.E. staining. The lipid metabolic profile was also altered with increased phospholipid and sphingolipid metabolites in broncho-alveolar lavage fluid (BALF) after PM2.5 instillation. Organic component analysis revealed that benzo[a]pyrene (BaP) is one of the most abundant and toxic components in the PM2.5 collected on the fiber filter. In vitro, BaP was used to treat A549 cells, an alveolar type II cell line. BaP (4 μM, 24 h) induced inflammation in the cells. Metabolomics analysis revealed that BaP (4 μM, 6 h) treatment altered the cellular lipid metabolic profile with increased phospholipid metabolites and reduced sphingolipid metabolites and free fatty acids (FFAs). The proportion of ω–3 polyunsaturated fatty acid (PUFA) was also decreased. Mechanically, BaP (4 μM) increased the phospholipase A2 (PLA2) activity at 4 h as well as the mRNA level of Pla2g2a at 12 h. The pro-inflammatory effect of BaP was reversed by the cytosolic PLA2 (cPLA2) inhibitor and chelator of intracellular Ca2+. This study revealed that BaP, as a component of PM2.5, induces pulmonary injury by activating PLA2 and elevating lysophosphatidylcholine (LPC) in a Ca2+-dependent manner in the alveolar type II cells., Graphical abstract fx1, Highlights • PM2.5 instillation increases pro-inflammatory lipid metabolism in the lung. • BaP promotes the metabolism of phospholipid in alveolar type II cells. • BaP activates cPLA2 in a Ca2+-dependent manner in alveolar type II cells.

As a traditional practice in grasslands, grazing significantly affects soil respiration (R-s). To improve our understanding of grassland carbon cycling, it is critical to partition the responses of soil respiration to grazing into autotrophic (R-a) and heterotrophic (R-h) respiration. In addition, it remains unclear how grazing patterns, such as warm- and cold-season grazing, influence R-s, and its components in alpine grasslands that are subject to increasing grazing pressure. Here, we conducted a six-year manipulative experiment combining with a meta analysis, to investigate the responses of 12, and its components to moderate grazing in a Tibetan alpine grassland. Grazing patterns included warm-season grazing by sheep during the growing seasons of 2008 to 2010 and simulating cold-season grazing by clipping during the non-growing seasons of 2011 to 2013. Our results showed that warm-season grazing minimally affected R-s, while cold-season grazing significantly increased R-s, by 13.1%. This result was supported by a meta-analysis at seven grassland sites across the Tibetan Plateau. Further, we found that warm-season grazing did not affect R-a or R-h, whereas cold-season grazing enhanced Ra (23.2%) more than R-h (4.9%). Cold-season grazing affected 12, and R-a differently depending on interannual variation in climate conditions. A significant increase of 17.1% and 26.3%, respectively, was recorded in dry and cold years, but no change was recorded in wet and warm years. This study highlights the differential responses of R, components to grazing, and suggests that different grazing patterns should be considered when evaluating future carbon cycles in grazing ecosystems on the Tibetan Plateau.

Objectives Heteroresistance is a phenomenon in which there are various responses to antibiotics from bacterial cells within the same population. Here, we isolated and characterised an imipenem heteroresistant Acinetobacter baumannii strain (HRAB-85). Methods The genome of strain HRAB-85 was completely sequenced and analysed to understand its antibiotic resistance mechanisms. Population analysis and multilocus sequence typing were performed. Results Subpopulations grew in the presence of imipenem at concentrations of up to 64μg/mL, and the strain was found to belong to ST208. The total length of strain HRAB-85 was 4,098,585bp with a GC content of 39.98%. The genome harboured at least four insertion sequences: the common IS Aba1 , IS Aba22 , IS Aba24 , and newly reported IS Aba26 . Additionally, 19 antibiotic-resistance genes against eight classes of antimicrobial agents were found, and 11 genomic islands (GIs) were identified. Among them, GI3, GI10, and GI11 contained many ISs and antibiotic-resistance determinants. Conclusions The existence of imipenem heteroresistant phenotypes in A. baumannii was substantiated in this hospital, and imipenem pressure, which could induce imipenem-heteroresistant subpopulations, may select for highly resistant strains. The complete genome sequencing and bioinformatics analysis of HRAB-85 could improve our understanding of the epidemiology and resistance mechanisms of carbapenem-heteroresistant A. baumannii .

Business English as a lingua franca (BELF) is gaining popularity in international business and research domains. In the framework of the socio-cognitive approach, this article examines the role of metapragmatic expressions (MPEs) in creating common ground (CG) in BELF meeting interactions. Based on the data from one business meeting drawn from the Vienna-Oxford International Corpus of English, it is found that the speakers mainly employ four types of MPEs, i.e. commentaries, speech-action descriptions, message glosses and evidentials, as pre-emptive or corrective strategies when they are aware of potential or actual problems or difficulties in interactions. MPEs are intended to activate shared sense (e.g. previous agreement, mutual experiences and company policy) and current sense (e.g. different or new perspectives, evaluations and sympathy) to construct emergent CG of knowledge and emergent CG of affiliation to achieve mutual understanding in BELF meeting interactions.

Carcinoembryonic antigen (CEA) is an important biomarker in cancer diagnosis. Here, we present an efficient, selective lateral-flow immunoassay (LFIA) based on magnetic nanoparticles (MNPs) for in situ sensitive and accurate point-of-care detection of CEA. Signal amplification mechanism involved linking of detection MNPs with signal MNPs through biotin-modified single-stranded DNA (ssDNA) and streptavidin. To verify the effectiveness of this modified LFIA system, the sensitivity and specificity were evaluated. Sensitivity evaluation showed a broad detection range of 0.25-1000ng/ml for CEA protein by the modified LFIA, and the limit of detection (LOD) of the modified LFIA was 0.25ng/ml, thus producing significant increase in detection threshold compared with the traditional LFIA. The modified LFIA could selectively recognize CEA in presence of several interfering proteins. In addition, this newly developed assay was applied for quantitative detection of CEA in human serum specimens collected from 10 randomly selected patients. The modified LFIA system detected minimum 0.27ng/ml of CEA concentration in serum samples. The results were consistent with the clinical data obtained using commercial electrochemiluminescence immunoassay (ECLIA) (p

Tungsten oxide (WO3) as precursor was prepared by one-step hydrothermal method and then nitrogenized under ammonia atmosphere to obtain tungsten nitride (WN) electrocatalyst for oxygen reduction reaction (ORR). Different morphological structures such as rod-like, needle-like and urchin-like of WO3 were carried out by adding morphology control agents and adjusting hydrothermal time. WN catalyst from needle-like WO3 with minimum section diameter emerged outstanding ORR performance (rapid kinetics of oxygen reduction and approach to four-electron reaction) for its nanoscale particles, low agglomeration and nitrogen doping. The low-cost WN possessed fine durability and better methanol resistance compared to commercial Pt/C, which were also crucial issues in fuel cells.

Cobalt modified tungsten nitride catalyst supported on carbon nanotubes (Co-WN/CNTs) was synthesized through electrospinning and heat treatment, in which WN and Co were uniformly dispersed in N-doped CNTs. The migration of small-sized Co in graphitized carbon results in formation of CNTs when heat-treated. WN, Co element, Co3+, and organic-N constitute multiple active sites of the catalyst, and high graphitized carbon provides strong charge transfer ability and good conductivity for electron. The excellent oxygen reduction activity, efficient four-electron reactions and the stable multiple cycles of Co-WN/CNTs catalyst depend on the multiple active sites and their high dispersion in graphitized carbon.

The main objective of this paper is to study the stability and stabilization problems for a class of impulsive switched systems with inappropriate impulsive switching signals under asynchronous switching. Here, “inappropriate” means that the impulse jump moment may be inconsistent with the asynchronous switching moment or the system switching moment. And “asynchronous” implies that the switching of controller modes lags behind that of system modes. The hybrid case of stable or unstable subsystems combining with stable and unstable impulses is explored. A novel Lyapunov-like function is constructed, which is discontinuous at some special instants, including the switching instants, the instants when the system modes and filter modes are matched, and the impulse jump instants. Based on the novel multiple Lyapunov-like function, the sufficient conditions for the closed loop system to be globally uniformly exponentially stable (GUES) are obtained with admissible edge-dependent switching signals. Furthermore, by excogitating the state-feedback switching controller, the gain matrix of the controller can be obtained by solving the linear matrix inequalities. Finally, two numerical examples and simulation results are given to prove the effectiveness of our main results.