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• CASA, RUSLE, and InVEST were utilized for ecological environment assessment. • We analyzed the ecological environment of Pingtan Island from multiple aspects. • We conducted correlation analysis from both natural and socio-economic perspectives. • The impact of GDP and population on ecological service is large in our study. In response to the needs of national ecological construction, especially the construction of high-quality marine space and reasonable use of the marine environment, Pingtan Island as a demonstration area of China's environmental construction, this study evaluates the quality of its ecological environment, which provides reference for the protection of the future ecological environment. In this study, CASA (Carnegie-ames-stanford approach), RUSLE (Revised universal soil loss equation) and InVEST (Integrated valuation of ecosystem services and trade-offs) models were selected for ecological environment assessment in the Pingtan Island. The NPP (Net primary productivity) calculated by CASA model, soil erosion data calculated by RUSLE and habitat quality, total carbon, water yield, and sediment delivery ratio calculated by InVEST model showed that the ecological environment quality and ecological service function of the study area had a weakening trend from 2000 to 2010. In particular, there was a tendency to weaken the water yield and sediment delivery ratio in the Pingtan Island between 2000 and 2010. The weakening trend during 2010 and 2020 was much higher than that during 2000 and 2010. The main influencing factor of each ecological service function is NDVI, which indicates that the degree of vegetation cover is the key factor determining the ecological service function. The impact of GDP and population on the ecological service functions is also large, which indicates that with the acceleration of urbanization, the ecological service function of the research area has been negatively affected. Changes in ecological services and ecological restoration functions are significant for local sustainable development. [ABSTRACT FROM AUTHOR]

This study investigated the tribological properties of Cu 36 Zr 48 Ag 8 Al 8 BMG against Cu 36 Zr 48 Ag 8 Al 8 BMG under H 2 SO 4 corrosive conditions with different concentrations. Results show that Cu 36 Zr 48 Ag 8 Al 8 BMG exhibits good tribological behaviors under H 2 SO 4 conditions. Especially, when the material was soaked in 15 wt% H 2 SO 4 solution, the friction coefficient and wear rate can be as low as 0.10 ± 0.01 and (0.28 ± 0.23) × 10−6 mm3 N−1m−1. It is mainly attributed to the existence of metal oxide films formed by surface oxidation and passivation actions as well as the fluid lubricating films formed by H 2 SO 4 solution and dissolution reaction products ( A l 2 (S O 4) 3 and CuS O 4 ) on the worn surfaces. These perfect properties promote Cu 36 Zr 48 Ag 8 Al 8 BMG to have the promise to replace the stainless steel under H 2 SO 4 corrosive condition. • Cu 36 Zr 48 Ag 8 Al 8 BMG possess higher corrosion resistance than 316 SS in H 2 SO 4 solution. • Self–mated BMG present low friction and wear rate under H 2 SO 4 conditions. • The formed metal oxides films and fluid lubricant films improve the tribological properties. • The formed metal oxides films promote BMG to have high corrosion resistance. • Metal oxides films and fluid lubricant films are changed with the variation of solutions. [ABSTRACT FROM AUTHOR]

• Waterborne PAI-graphite coatings are green lubricating materials. • Waterborne PAI-graphite coatings exhibit superior mechanical and tribological properties. • Tribological mechanisms of waterborne coatings were systematically investigated. • Tribological properties of waterborne coatings under different experimental conditions were explored. The purpose of this work is to fabricate novel green waterborne PAI-graphite bonded solid-lubricating coatings (BSLCs) with superior mechanical and tribological properties so as to replace the reported organic-solvent BSLCs to some extent, and further investigate the lubricating mechanisms. The work indicates that, the preparation of the waterborne PAI-graphite BSLCs have greatly reduced the utilization rate of organic solvents (without the usage of organic solvent). The basic physicochemical properties of the coatings have reached the corresponding level of the organic-solvent BSLCs. When the mass ratio of waterborne PAI resin and graphite is 1.2, the waterborne graphite-based BSLCs exhibit superior mechanical and tribological properties, which are comparable to those of the reported organic-solvent BSLCs. The variation of tribological properties of the waterborne PAI-graphite coatings under diversified applied loads and reciprocating frequencies were explored systematically for the sake of the better understanding of environmental adaptability of the waterborne PAI-graphite BSLCs. [ABSTRACT FROM AUTHOR]

In the article, a novel and facile method for hydrophilic modification of nano-lanthanum trifluoride particles was designed, the experimental results reveal that the surface of the nano-lanthanum trifluoride are absorbed with cross-linked molecules via electrostatic attraction and hydrogen bonds to further improve the water-dispersion capacity of nano-lanthanum trifluoride. In addition, the modified nano-lanthanum trifluorides achieve nano-scale dispersion in water-based bonded solid lubricating coatings, and 5 wt.% of modified lanthanum trifluoride into coatings can greatly enhance the mechanical and tribological properties of water-based coatings, which are superior to that of organic-solvent based coatings. Furthermore, the modified lanthanum trifluoride for promoting the wear resistance of the coatings illustrates more significant compared to unmodified lanthanum trifluoride and lanthanum trifluoride wetted by acrylic surfactant. [ABSTRACT FROM AUTHOR]

A series of novel environmental friendly bonded solid lubricating composite coatings were prepared via facile paint spray method and by virtue of adjusting the proportion of the composition of the coating (PTFE, water-based polyamide-imide (PAI) and LaF 3 ). The experimental results suggested that the physical, chemical and tribological properties of the water-based PAI-PTFE bonded solid lubricating composite coating with 5 wt% LaF 3 are comparable to that of organic-solvent resin composite coatings, additionally, the preparation of water-based resin bonded solid lubricating coatings have greatly minimized usage of fossil fuel. Furthermore, the work also explored the variation laws of tribological properties of the coatings under different applied load and slipping frequency. [ABSTRACT FROM AUTHOR]

Recent reports regarding metal halide semiconductors of perovskite nanocrystal structures have presented us a promising future on their optoelectronic applications such as laser and light harvesting devices. In this paper, all-inorganic perovskites CsPbX 3 (X=Cl, Br and I) quantum dots (QDs) with tunable fluorescence from 400 nm to 700 nm were prepared by a facile hot-injection method. Besides, random lasing with coherent feedback was observed in films of CsPbX 3 QDs. Under 400 nm optical excitation at room temperature, sharp lasing peaks emission at around 427 nm, 527 nm and 539 nm with low pump thresholds intensity were achieved by halide substitution. The dynamic fluorescence from one single quantum dot also was detailed investigated. These results demonstrated that all-inorganic perovskites could be used as low-threshold and wavelength-tunable gain materials for lasing application at room-temperature. [ABSTRACT FROM AUTHOR]

Waterborne bonded solid lubricating coatings (BSLCs) are normally prepared by physical blending, the basic components of which, however, exhibit poor wetting and dispersing properties and interfacial bonding strength. This article focuses on the structural design and chemical modification of waterborne polyurethane to optimize the adhesion of BSLCs thereof. By virtue of further compounding with polytetrafluoroethylene emulsions, a series of novel environmentally-friendly waterborne BSLCs have been successfully prepared, and then by adjusting the interface bonding between the resin and the lubricant in the coatings, the lubrication and wear resistance of the prepared BSLCs are systematically optimized. Experimental results demonstrate that the prepared waterborne BSLCs can effectively reduce the consumption of fossil resources and show superior physicochemical properties, lubrication and wear resistance, which are comparable to those of the organic solvent-based coatings. Furthermore, through systematic analysis of the damage morphology, structural variations and chemical compositions of the wear marks, the tribological mechanisms of the prepared BSLCs are illustrated. The current study help to promote the development of environment-friendly solid lubricating materials, and provides alternatives for the use of organic solvent-based BSLCs for reducing pollutions. [Display omitted] • Adhesion strength of the waterborne polyurethane is enhanced via chemical modification from level 5 to level 1. • Waterborne polyurethane BSLCs are novel green lubricating materials with superior physicochemical properties. • Tribological performances of waterborne coatings with mass ratio of 0.9 are comparable to the organic-based coatings. • Tribological mechanisms are systematically investigated concerning the wear marks. [ABSTRACT FROM AUTHOR]

The bulk metallic glass has the potential application used in mechanical moving parts serving in corrosive environments because of its excellent mechanical, tribological properties and corrosion resistance. Here, Zr 48 Cu 36 Al 8 Ag 8 BMG/graphite composites with a 3D lubricating layer are prepared via an in-situ integrated technique. The synergism of the graphite lubrication and the micro-texture effect could significantly smooth the friction coefficient curve and reduce wear. Although seawater has a lubricating effect, the corrosion affects the reliability of BMG/graphite composites. By applying an external potential to the friction system, the effect of preventing galvanic phenomena at the interface between the alloy and graphite and improving the wear resistance of the composite material can be effectively achieved. • BMG/graphite self-lubricating composite was prepared via an in-situ integrated technique. • The material has a 3D lubricating layer near surface. • Graphite lubricating films and micro-textured effect improve tribological properties. • Corrosion and wear resistance in seawater can further improved by applying an potential. [ABSTRACT FROM AUTHOR]

The tribological behaviors of the high-performance Cu 36 Zr 48 Ag 8 Al 8 bulk metallic glass (BMG) under dry-sliding, deionized water and NaOH solution conditions were systematically investigated and the corresponding wear mechanisms were revealed via analyzing the chemical composition and topography of wear track. The results illustrate that the Cu 36 Zr 48 Ag 8 Al 8 BMG exhibits tribological properties superior to those of 316 stainless steel under different friction conditions, especially in a NaOH solution. During friction sliding, the formation of uniform and continuous metal-oxide layers on the surface can enhance its wear resistance and protect it from further corrosion by OH−. Furthermore, the NaOH solution and the dissolved products on the frictional surface form fluid-lubricating films, which may also reduce the friction coefficient and wear rate of the material. • Self–mated CuZr–based BMG present low friction and wear rate under NaOH conditions. • The formation of metal oxides layers and fluid lubricating films improve properties. • Corrosion resistance benefit from amorphous structure and metal oxide layers. • Cu 36 Zr 48 Ag 8 Al 8 BMG exhibit good environmental adaptability under NaOH conditions. [ABSTRACT FROM AUTHOR]

• Two kinds of aqueous PTFE based coatings are green lubricating materials. • The basic physicochemical properties of two aqueous PTFE based coatings are comparable to that of organic-solvent based coatings. • Aqueous PTFE-ADPs based coatings exhibit superior mechanical and tribological performances to that of PTFE-PPs based coatings. • Tribocorrosive properties and active mechanism under diversified environments are thoroughly investigated. In the paper, the two kinds of environment-friendly aqueous PTFE based bonded solid lubricating coatings were prepared via facial paint spraying method, significantly reducing the waste of organic solvents. The basic physicochemical properties of two kinds of aqueous PTFE based coatings are comparable to that of organic-solvent based coatings. In addition, the tribocorrosive properties and active mechanism of two kinds of aqueous PTFE based coatings were thoroughly investigated under diversified environments, and the results illustrate that aqueous PTFE-ADPs based coatings exhibit superior mechanical and tribological performances to that of PTFE-PPs based coatings, and the tribocorrosive properties of two PTFE based coatings show major variation under different environments, which provides valuable references for environmental adaptability of the aqueous PTFE-based coatings, and further promotes the development of bonded solid lubricating coatings toward the direction of low carbon and environmental protection. [ABSTRACT FROM AUTHOR]

• Propose a new method to calculate fracture number and length of methane deflagration fracturing technology. • Conduct fracturing experiments with large-sized samples to verify the technical feasibility of methane deflagration fracturing technology. • The methods have high accuracy and are also suitable for other fracturing technologies. The innovative Methane in-situ deflagration fracturing technology offers several benefits. It can prevent formation pollution and eliminates the need for complex treatment procedures for backflow materials. Additionally, it reduces ground transportation expenses and is poised to become a highly effective and eco-friendly waterless fracturing technology. This paper suggests methods for determining the number and length of fractures in oil and gas well stimulation, considering the main influencing factors. The fracture number is calculated using mass conservation principles, while the fracture length is determined using the crack propagation model. The fracturing experiments with large-sized samples were conducted to verify the technical feasibility of the new fracturing technology and fill the gap in large-scale physical model experimental research for deflagration fracturing technology. Following the experiment, compare experimental data with calculated data, and analyze the factors that affect the fracture number and length. The results indicate that both methods are highly feasible and possess strong predictive accuracy. It is advised that to enhance the fracturing effect on formations with high crustal stress, it is beneficial to appropriately increase the peak pressure, reduce the pressure rate, and increase the fracturing time while ensuring that the wellbore remains undamaged. Moreover, these proposed methods are versatile and adaptable, making them suitable for explosive fracturing within hydraulically fractured formations and high-energy gas fracturing technology. [ABSTRACT FROM AUTHOR]

• Cyclic test on prestressed precast piers with high-strength bars is performed. • Effects of high-strength ED bars on seismic resilience are firstly witnessed. • Proposed fiber-based FE model is efficient for the novel PPC pier system. Precast segmental bridge piers are vigorously pursued, especially in low- and medium- seismicity regions, for their merits in accelerating construction, reducing environmental/traffic disturbances, enhancing quality control, etc. Recently, unbonded tendons are utilized to reduce the residual displacement and to facilitate fast rehabilitation of key bridges in the urban traffic system. To further enhance the resilience, prestressed precast segmentally-erected (PPC) piers were fabricated and tested, reinforced with a hybrid of unbonded tendons and high-strength (H) energy dissipation (ED) bars. In this study: (1) cyclic loading tests for the PPC piers with "H" ED bars were reported, and the seismic resilience was quantitatively evaluated and compared with the PPC piers with normal-strength (L) ED bars; (2) the computationally efficient fiber-based finite element (FE) model is developed for the tested PPC piers. Experimental results demonstrated that the "H" ED bars brought out apparent amelioration, in terms of load-carrying, ductility and self-centering capacities. In consideration of rising seismic resilience, "H" ED bars are recommended to replace currently large-scale adopted "L" ED bars in the PPC pier of vital bridges. Through validation with experimental results, the proposed fiber-based FE model is able to provide satisfactory predictions for seismic responses of the tested PPC piers. [ABSTRACT FROM AUTHOR]

• We reconstructed hundreds of shale pore networks using FIB-SEM and QSGS. • We developed a parallelized MRT-LBM to model slip and early transition flows. • We studied the effects of multiscale heterogeneity on gas permeability. • Slippage diminishes with increasing tortuosity and surface curvature/roughness. • We empirically correlated the proportionality factor, porosity and tortuosity. Gaseous microflow in nanoporous media of ultratight shale strata was reexamined. Hundreds of nanoscale pore network samples of the Wufeng and Longmaxi shale matrix were reconstructed by ultra-precise FIB-SEM experiments and the Quartet Structure Generation Set (QSGS) method. An OpenMP-based, high-performance, parallelized MRT-LBM model to predict shale gas flow in reconstructed nanoporous media was developed accordingly. The MRT-LBM model was validated against the analytical solutions, molecular dynamics simulations, and discrete velocity method. The MRT-LBM accurately predicted gaseous microflow in the continuum, slip, and early transition flow regimes. Using this solver, extensive pore-scale simulations of the gas transport in nanoscale pore networks were performed to study the effects of pore heterogeneity and slippage effects on the apparent permeability of shale gas. It has been known that gas slippage and Knudsen diffusion dramatically improve gas flow in a single capillary. Hence, permeability models based on a bundle of capillaries followed the increasing gas flow predictions. However, our modeling results revealed that gas slippage is suppressed by pore tortuosity, wall curvature, and surface roughness. The proportionality factor of the Klinkenberg model decreases with increasing tortuosity and decreasing porosity. We develop an apparent permeability model appropriate for low-porosity and large-tortuosity shale nanoporous media, with a corrected proportionality factor. [ABSTRACT FROM AUTHOR]

In this study, we report a simple way to fabricate VO x thin film from pure-water solution, as the hole extraction layer (HEL) for perovskite hybrid solar cells (pero-HSCs). Furthermore, an aminopropanoic acid (APPA) interfacial layer is used to modify VO x thin film for reducing the charge carrier recombination rate. As a result, the pero-HSCs with the VO x /APPA HEL exhibits better device performance than that of the pero-HSCs with the VO x HEL and the pero-HSCs with poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonate) HEL. Moreover, the pero-HSCs with the VO x /APPA HEL exhibits hysteresis-free characteristics. All these results indicate that we report a simple approach to realize high performance of perovskite hybrid solar cells. [ABSTRACT FROM AUTHOR]

Allergic rhinitis (AR) is a common disease worldwide. Imbalances in T helper (Th) cell differentiation and the dysregulation of related cytokines form the immunological basis of AR. miR-126 may play an important regulatory role in AR as a new marker and predictor of the disease. Therefore, the aim of this study was to explore the regulatory effects of miR-126 on Th cell differentiation and cytokine expression in AR. T lymphocytes and rat models were transfected with a miR-126 mimic and an inhibitor. The expression of miR-126 and Th cell-related cytokines was detected by RT-qPCR and western blotting. The serum IgE levels were detected using ELISA. In the nasal mucosa, pathological changes were observed by HE staining, protein expression was detected by immunohistochemistry, and the differentiation ratio of Th cell subsets was detected by flow cytometry. During the occurrence and development of AR, the expression of miR-126 and the IgE levels were increased in the AR group. The number of Treg cell subsets decreased in the AR rats, increased after the miR-126 agomir intervention and decreased after miR-126 antagomir intervention. The number of Th1 and Th2 cell subsets increased in the AR rats, decreased after miR-126 agomir intervention and increased after the miR-126 antagomir intervention. We propose that miR-126 may be involved in the pathogenesis of AR by positively regulating the expression of Treg cytokines and negatively regulating the expression of the Th1 and Th2 cytokines. [ABSTRACT FROM AUTHOR]

• An observational cohort study of 191 ICU patients with sepsis for Tβ4. • Prognostic value of Tβ4 in ICU patients with sepsis. • Lower Tβ4 stages were associated with higher odds of poor prognosis. Sepsis is a systemic inflammatory response syndrome, associated with high risk of acute kidney injury (AKI) and in-hospital mortality. Thymosin beta-4 (Tβ4) is an actin-sequestering protein that can prevent inflammation in several tissues. Thus, we studied the role of Tβ4 in sepsis. The Tβ4 concentrations were prospectively measured in 191 patients within 6 h of the intensive care units (ICU) admission with diagnosis of sepsis. The cohort was divided into Tβ4 concentration tertiles: 1.19–7.11 ng/ml (n = 64), 7.12–11.01 ng/ml (n = 64), and 11.02–28.10 ng/ml (n = 63). Of 191 patients, 92 patients developed AKI, 24 of whom received continuous renal replacement therapy (CRRT), 29 patients died within 7 days, and 53 patients died within 28 days. Lower Tβ4 stages were correlated with poor prognosis, including AKI(odds ratio [OR], 2.102 per stage lower; 95% confidence interval [CI], 1.448 to 3.050; P < 0.001), CRRT(OR, 2.346 per stage lower; 95% CI, 1.287 to 4.276; P = 0.005), 7-day mortality(OR, 1.755 per stage lower; 95% CI, 1.050 to 2.935; P = 0.032), and 28-day mortality(OR, 1.821 per stage lower; 95% CI, 1.209 to 2.743; P = 0.004). Kaplan-Meier analysis also demonstrated that patients with lower Tβ4 stages had a high risk of AKI and death. In addition, the area under the curve (AUC) of Tβ4 for predicting AKI, CRRT, 7-day mortality, and 28-day mortality were, respectively, 0.702 (95% CI 0.628–0.776), 0.717 (95% CI 0.592–0.842), 0.694 (95% CI 0.579–0.808), and 0.682 (95% CI 0.598–0.767). Lower Tβ4 stages are associated with higher odds of poor prognosis in ICU patients with sepsis. [ABSTRACT FROM AUTHOR]

• Aqueous PAI-MoS 2 -graphite bonded solid lubricating coatings are novel green lubricated materials. • Aqueous coating with the MRGM of 0.3 exhibits more excellent mechanical and tribological properties. • Tribological mechanisms of aqueous coatings are systematically investigated concerning the morphology, structure and chemical compositions of wear scars. In this paper, a series of the environmental-friendly aqueous PAI-MoS 2 -graphite bonded solid-lubricating coatings (BSLCs) are prepared depending on the design concept of the recombination of two-component lubricant and aqueous resin, and the mechanical strength and wear resistance of the coatings are deeply optimized by virtue of the synergy of the components of coatings. The experimental results demonstrate that the successful preparation of aqueous BSLCs greatly reduces the utilization of toxic organic solvents and is conducive to environmental protection and resource conservation. Doping an appropriate amount of graphite into the aqueous BSLCs is beneficial to maximize the promotion of the mechanical and tribological properties of the coating, and when the mass ratio of graphite to MoS 2 (MRGM) is 0.3, the mechanical strength, friction reduction and wear resistance of the coatings display the comparable level as that of the organic-solvent based BSLCs. Based on the analysis of the variations of the morphology, structure and chemical composition of the wear scars, the corresponding active mechanisms on the mechanical and tribological properties of the coating are investigated in depth. [ABSTRACT FROM AUTHOR]

More and more countries utilize nurse anesthetists as an anesthetic care provider to make up for the insufficiency of anesthesiologists. To examine whether introducing nurse anesthetists with expanded scope of practice to anesthetic care would jeopardize the safety of patients and quality of anesthetic care. This observational study used an interrupted time series design. A metropolitan teaching cancer hospital located in Southwest China. 24290 patients with surgical procedures under general anesthesia from January 2015 to December 2017 were included. In May 2016, nurse anesthetists with expanded scope of practice were introduced to anesthetic care. Administrative and medical record data were accessed to identify the occurrence of anesthetic outcomes including failed tracheal intubation and inability to ventilate with mask, aspiration, problem with airway in the post-anesthesia care room, hypothermia (temperature ≤ 35°C or chills), unplanned stay in the post-anesthesia care room longer than 3 hours, unexpected intensive care unit admission, reintubation, vascular and cardiopulmonary disorders and death. Statistical process control analysis was conducted to test special cause variation in outcomes over time. Findings demonstrated significant decrease in the proportion of patients staying in the post-anesthesia care room longer than 3 hours and with hypothermia following nurse anesthetists introduced to anesthetic care. Other anesthetic outcomes were not significantly changed. The results demonstrate that involvement of nurse anesthetists with expanded scope of practice in anesthetic care did not jeopardize patients' safety or quality of anesthesia. Moreover, it may have beneficial impact in preventing prolonged stay in the post-anesthesia care room and hypothermia. Further research is required to examine the impact of involvement of nurse anesthetists in anesthetic care across all clinical contexts. [ABSTRACT FROM AUTHOR]