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Response Surface Method (RSM) has been widely used for flammable cloud size prediction as it can reduce computational intensity for further Explosion Risk Analysis (ERA) especially during the early design phase of offshore platforms. However, RSM encounters the overfitting problem under very limited simulations. In order to overcome the disadvantage of RSM, Bayesian Regularization Artificial Neural (BRANN)-based model has been recently developed and its robustness and efficiency have been widely verified. However, for ERA during the early design phase, there seems to be room to further reduce the computational intensity while ensuring the model's acceptable accuracy. This study aims to develop an integrated method, namely the combination of Center Composite Design (CCD) method with Bayesian Regularization Artificial Neural Network (BRANN), for flammable cloud size prediction. A case study with constant and transient leakages is conducted to illustrate the feasibility and advantage of this hybrid method. Additionally, the performance of CCD-BRANN is compared with that of RSM. It is concluded that the newly developed hybrid method is more robust and computational efficient for ERAs during early design phase.

ETV5 is an ETS transcription factor that has been associated with obesity in genomic association studies. However, little is known about the role of ETV5 in hepatic lipid metabolism and nonalcoholic fatty liver disease. In the current study, we found that ETV5 protein expression was increased in diet- and genetically induced steatotic liver. ETV5 responded to the nutrient status in a mammalian target of rapamycin complex 1 (mTORC1)–dependent manner and in turn, regulated mTORC1 activity. Both viral-mediated and genetic depletion of ETV5 in mice led to increased lipid accumulation in the liver. RNA sequencing analysis revealed that peroxisome proliferator–activated receptor (PPAR) signaling and fatty acid degradation/metabolism pathways were significantly downregulated in ETV5-deficient hepatocytes in vivo and in vitro. Mechanistically, ETV5 could bind to the PPAR response element region of downstream genes and enhance its transactivity. Collectively, our study identifies ETV5 as a novel transcription factor for the regulation of hepatic fatty acid metabolism, which is required for the optimal β-oxidation process. ETV5 may provide a therapeutic target for the treatment of hepatic steatosis.

The successful joining of carbon fiber-reinforced aluminum matrix (Cf/Al) composites and TC4 alloy can produce composite structure and meet the demands of lightweight in aerospace field. Up to now, few experimental researches have been reported on the joining of Cf/Al composites and TC4 alloy. In this study, the AgCu foils and Ni–Al–Zr compact were designed for the self-propagating high-temperature synthesis joining of these two materials. Cf/Al composites were joined with a reactive Ti plated on its joining surface. The typical microstructure of TC4/(AgCu/Ni–Al–Zr/AgCu)/Ti/Cf/Al joint was analyzed, and the effects of joining condition on microstructural evolution of the SHS joint were investigated. A thin reaction layer of Ni–Al–Ti intermetallic compounds was formed adjacent to the TC4 alloy. As a result, AgCu foils could reduce the effect of reaction heat on the substrates and improve the joint shear strength. When the thickness of AgCu foils reaches 150 μm, the Ni–Al–Zr interlayer mainly acts as auxiliary heat source. High joining pressure caused the active elements to diffuse into Cf/Al composites and weakened the shear strength of the joint. Finally, the joint shear strength could reach 36.4 MPa when the AgCu foils were 50 μm and the joining pressure was 2 MPa.

The spatial distribution of the sediment nitrogen in ten typical estuaries of Lake Taihu was determined. A simple quantitative estimation model and principal component analysis (PCA) method were applied to find the source and major factors of estuarine sediment nitrogen loading. The average concentrations of total nitrogen (TN), organic nitrogen (Org-N), ammonium nitrogen and nitrate-nitrogen in the sediments of the ten estuaries were 1315.5, 1220.1, 82.53 and 6.45 mg/kg, with the organic fraction dominating. Results showed a significant difference for the TN concentration in sediments of different estuaries, which was mainly caused by geographical location, land use type and vegetation restoration measures. An important result was that sediment nitrogen in 80% of the estuaries was mainly originated from autochthonous algae and presettled organic matter, although there has been continuous pollution input from inflow rivers. The source estimation results found that the autochthonous aquaculture excretion, algae and hydrophyte debris and buried biodetritus accounted for 58.9% of the total nitrogen loading, which dominated the nitrogen sources compared with the pollution input. In addition, the PCA method was used to find that phosphorus loading and redox conditions were the major limiting factors affecting the distribution of inorganic and , respectively.

Redox-responsive theranostic nanoparticles based on poly-(N-e-carbobenzyloxy- l -lysine) (PZLL) grafted hyaluronan (HA) (HA-g-SS-PZLL) copolymers were constructed for hepatocellular carcinoma diagnosis and therapy. These hyaluronan derivatives formed nanoparticles via a self-assembly process in aqueous solution at low concentration. Theranostic nanoparticles were obtained after loading hydrophobic doxorubicin (DOX) and superparamagnetic iron oxide (SPIO) into the core of the nanoparticles via a dialysis method. Theranostic nanoparticles exhibited redox triggered DOX release behavior, and faster DOX released from theranostic nanoparticles was detected under a reducing environment compared with slow DOX release under a normal physiological environment. Confocal laser scanning microscopy (CLSM), flow cytometry and Prussian blue staining against HepG2 cells demonstrated that HA-g-SS-PZLL theranostic nanoparticles were capable of delivering DOX and SPIO into the cells. The analysis of the anticancer effect revealed that the HA-g-SS-PZLL theranostic nanoparticles shown higher cytotoxicity against HepG2 cells than DOX-loaded HA-g-PZLL nanoparticles. In vitro T2 magnetic resonance imaging (MRI) results exhibited that theranostic nanoparticles showed a good contrast enhancement effect, and the r2 relaxivity value was approximately 231 Fe mM−1 s−1. Finally, the theranostic nanoparticles acted as nanoprobes for HepG2 tumor-bearing BALB/c mice for in vivo MRI. Therefore, HA-g-SS-PZLL copolymers have great potential as theranostic nanoparticles for tumor-targeted diagnosis and treatment.

The synthesized imidazoline phosphate quaternary ammonium salt has low stability, which is spontaneously and rapidly hydrolyzed to the long-chain fatty acid amide (LFA). The hydrolysate (LFA) has been found to be an efficient inhibitor for Q235 steel against CO2 corrosion, which yields a maximum value above 90% at a concentration of 1000 mg L−1. The LFA inhibitor acts as an anodic type inhibitor and its inhibition mechanism is a “negative catalysis effect”. The heteroatoms in the acyl, amine and phosphate groups in the LFA molecule are the active centers to bond with Fe atoms to form a chemisorbed film on the steel surface.

Polysaccharide biopolymers are biomacromolecules derived from renewable resources with versatile functions including thickening, crosslinking, adsorption, etc. Possessing high efficiency and low cost, they have brought wide applications in all phases of petroleum recovery, from well drilling to wastewater treatment. The biopolymers are generally utilized as additives of fluids or plugging agents, to correct the fluid properties that affect the performance and cost of petroleum recovery. This review focuses on both the characteristics of biopolymers and their utilization in the petroleum recovery process. Research on the synthesis and characterization of polymers, as well as controlling their structures through modification, aims to develop novel recipes of biopolymer treatment with new application realms. The influences of biopolymer in many petroleum recovery cases were also evaluated to permit establishing the correlations between their physicochemical properties and performances. As their performance is heavily affected by the local environment, screening and testing polymers under controlled conditions is the necessary step to guarantee the efficiency and safety of biopolymer treatments.

Both cuticle and membrane lipids play essential roles in quality maintenance and disease resistance in fresh fruits. Many reports have indicated the modification of alternative branch pathways in epicuticular wax mutants; however, the specific alterations concerning lipids have not been clarified thus far. Here, we conducted a comprehensive, time-resolved lipidomic, and transcriptomic analysis on the “Newhall” navel orange (WT) and its glossy mutant (MT) “Gannan No. 1”. The results revealed severely suppressed wax formation accompanied by significantly elevated production of 36-carbon plastid lipids with increasing fruit maturation in MT. Transcriptomics analysis further identified a series of key functional enzymes and transcription factors putatively involved in the biosynthesis pathways of wax and membrane lipids. Moreover, the high accumulation of jasmonic acid (JA) in MT was possibly due to the need to maintain plastid lipid homeostasis, as the expression levels of two significantly upregulated lipases (CsDAD1 and CsDALL2) were positively correlated with plastid lipids and characterized to hydrolyze plastid lipids to increase the JA content. Our results will provide new insights into the molecular mechanisms underlying the natural variation of plant lipids to lay a foundation for the quality improvement of citrus fruit.

As a widely used antibiotic, sulfamethoxazole (SMX) has attracted increasing research attention. However, acidic condition was normally required for efficient SMX removal, and the energy variation of adsorption system is not fully elucidated. In this study, based on a typical mineral adsorbent of volcanic rock (VR), anion exchange was introduced by Polypyrrole (PPy) modification to overcome the electrostatic repulsion in alkaline environment, and site energy distribution (SED) theory was applied to explore adsorption behavior and mechanism on SMX from an energy perspective. The batch adsorption experiments and a series of complementary characterization were combined, confirming that pore filling and hydrogen bonding are the dominant adsorption mechanisms for SMX removal by VR. While the adsorption distinction between PPy supported VR (PPy-VR) and VR could be explained by electrostatic attraction, π-π electron donor-acceptor interaction (π-π EDA) and ion exchange, which further explained the wide pH application potential of modified sorbent. Moreover, Dubinin-Ashtakhov (DA) model was used to calculate the energy distribution, and PPy-VR exhibited a stronger adsorption affinity (Em=8.55-11.57KJ/mol) and energy heterogeneity (δe*=2.15-2.57) for SMX. The high-energy adsorption centers increased significantly (92.63%) after modification, which mainly attributed to π-π EDA and ion exchange introduced by PPy loading. The surface modification method provides a feasible idea for the improvement of application environment of adsorbents, and the analysis of SED is expected to promote the understanding of the connection between site energy and adsorption mechanism.

The application of an electric field promoted the migration of Na+ ions on the glass substrate. A sodium-depleted layer was formed on the glass surface, playing a key role in a successful bonding. Al accumulated at the glass/solder interface and enhanced the interfacial reactions. Al2O3 + Al2SiO5 + SnO, Cu6Sn5 and Cu3Sn reaction layers were respectively detected on both sides. The electric field and bonding temperature were varied to illustrate their impact on the interfacial bonding. The joint formation mechanism is discussed. When the bonding voltage was 1400 V and the bonding temperature was 400 °C, the glass/copper joint was free of cracks, and had a maximum shear strength of 11.5 MPa.

Catheter-associated urinary tract infections, caused by a build-up of biofilm on the catheter surface, are one of the most common nosocomial infections. For this work, we prepared a compositional variant of Tecoflex®, a commercial thermoplastic polyurethane (TPU), with peptide-like cationic pendant functional groups to study their effect on biofilm growth. Tecoflex® is used for fabrication of catheters and therefore a variant that shows decreased biofilm accumulation could have the potential to combat nosocomial infections. The cationic pendant groups were incorporated into the polyurethane composition similar to Tecoflex® by copolymerization of an amine functionalized N-substituted diol to give a cationic polyurethane (Tecoflex-NH3+). The antimicrobial properties of this cationic polyurethane were investigated using Escherichia coli, a Gram-negative bacterium and as confirmed by microscopy studies and bactericidal assays, the cationic polyurethane coating exhibited a contact-killing mechanism, and it significantly slowed down the build-up of biofilm compared to Tecoflex® coating. Moreover, the cationic polyurethane demonstrated minimal toxicity towards mammalian cells.

Predicting the hydrate formation condition is an important issue for determining high CO 2 content natural gas transport. The widely used Parrish-Prausnitz (P-P) model cannot predict the hydrate formation temperatures and pressures accurately for high CO 2 content natural gas. This paper introduced a simple correction factor into the P-P model, resulting in an improved P-P model. The analytical expression of this new parameter is developed by correlating the deviations of the predicted hydrate formation temperatures with the CO 2 molar fraction in the gas mixtures. A total of 140 sets of experimental data were applied to validate the proposed model, which covered wide pressure and CO 2 molar fraction ranges of 1.45–13.0 MPa and 0–90%, respectively. The results show that the improved P-P model balances a simple form with high accuracy. The average deviation of the improved P-P model is 0.098 °C, whereas that of the original P-P model is 2.424 °C. It is essentially comparable in its prediction ability to CSMGem software and the cell potential method when it is applied to predicting the hydrate temperatures of high CO 2 content natural gases.

Bacterial flagella are large extracellular protein organelles that drive bacteria motility and taxis in response to environmental changes. Previous research has focused mostly on describing the flagellar assembly, its rotation speed and power output. However, whether flagella are permanent cell structures and, if not, the circumstances and timing of their production and loss during the bacterial life cycle remain poorly understood. Here we used the single polar flagellum ofVibrio alginolyticusas our model and, usingin vivofluorescence imaging, revealed that the percentage of flagellated bacteria (PFB) in a population varies substantially across different bacterial growth phases. In the early-exponential phase, the PFB increases rapidly in respect to incubation time, mostly through widespread flagella production. In the mid-exponential phase, the PFB peaks at around 76% and the partitioning of flagella between the daughter cells is 1:1 and strictly at the old poles. After entering the stationary phase, the PFB starts to decline, mainly because daughter cells stop making new flagella after cell division. Interestingly, we discovered that bacteria can actively abandon flagella after prolonged stationary culturing, though cell division has long been suspended. Lack of glucose was found to be a major factor promoting flagellar disassembly. We also revealed that the active loss of flagella was initiated by breakage in the rod connecting the extracellular filament to the basal body formed by MS- and C-rings. Our results highlight the dynamic production and loss of flagellar filaments during the bacterial life cycle.

Citrus yellow vein clearing virus is a newly accepted member of the genus Mandarivirus in the family Alphaflexiviridae. The triple gene block proteins (TGBp1, TGBp2 and TGBp3) encoded by plant viruses in this family function on facilitating virus movement. However, the protein function of citrus yellow vein clearing virus (CYVCV) have never been explored. Here, we showed in both yeast two-hybrid (Y2H) and bimolecular fluorescence (BiFC) assays that the coat protein (CP), TGBp1 and TGBp2 of CYVCV are self-interacting. Its CP also interacts with all three TGB proteins, and TGBp1 and TGBp2 interact with each other but not with TGBp3. Furthermore, the viral CP colocalizes with TGBp1 and TGBp3 at the plasmodesmata (PD) of epidermal cells of Nicotiana benthamiana leaves, and TGBp1 can translocate TGBp2 from granular-like structures embedded within ER networks to the PD. The results suggest that these proteins could coexist at the PD of epidermal cells of N. benthamiana. Using Agrobacterium infiltration-mediated RNA silencing assays, we show that CYVCV CP is a strong RNA silencing suppressor (RSS) triggered by positive-sense green fluorescent protein (GFP) RNA. The presented results provide insights for further revealing the mechanism of the viral movement and suppression of RNA silencing.

Inflated membranes are popularly used in civil and aerospace engineering. They are flexible and their behaviors are featured by the interaction between the inner air pressure and deformation of the enveloping membrane (air–membrane interaction) which has not yet received attention in the literature. This paper aims at studying the air–membrane interaction and its influence on the static and dynamic properties of an inflated membrane by numerically analyzing a square ETFE (ethylene–tetrafluoroethylene) cushion. To account for the air–membrane interaction, the inner air was regarded as a linear potential fluid in developing the governing equations. The finite element model was derived from the discretized equations and verified through comparison with experimental results and those in the literature. Thereafter, the air–membrane interaction and its variation with influencing factors were investigated in the static and dynamic analysis by comparing results from the verified finite element model with the numerical solutions where the inner air was treated as the traction boundary conditions of the enveloping membrane. Results of this study indicate that (1) air–membrane interaction becomes more prominent with increasing external load and is gradually weakened with a rise in the frequency order; (2) air–membrane interaction makes the top membrane joined with the bottom membrane in the deformation and vibration; and (3) air–membrane interaction is strengthened with an increase in the initial inner pressure or geometric dimensions, but weakened when the membrane thickness or rise–span ratio increases. The present research is helpful to the understanding of the role the inner air plays in the behavior of inflated membranes, and may therefore improve the accuracy in analysis and the rationality in the design.

Peng-Robinson equation of state (PR EoS) is a reliable and widely used cubic EoS to predict natural gases thermodynamic properties. However, large deviations between the calculated compressibility factor values and the realistic values are observed when it is applied to the high volume CO2-content natural gas. In order to enhance its applicability, a new correction parameter associated with three-parameters (the reduced temperature Tr, reduced pressure Pr and CO2 volume content) is introduced into the attractive term of PR EoS by fitting the deviations between 267 groups of experimental compressibility factors and corresponding calculation values. The results reveal that the average absolute deviation between experimental data and predicted compressibility factors from the improved PR EoS is 2.708% when the pressures range from 3 MPa to 15 MPa, temperatures range from 263.15 K to 313.15 K and CO2 volume contents range from 9.84% to 100%. The deviation is reduced by 9.61% when compared to that of the original PR EoS. The results also demonstrate that this improved PR EoS has better performance than PRSV, PRTwu BWRS EoSs, and is essentially comparable in predictability to PC-SAFT EoS.

To improve the compressibility factor prediction of CO 2 -content natural gas, this short communication proposes a new combinational Stewart-Burkhardt-Voo (SBV) + Prausnitz-Gunn (PG) mixing rule for the Lee-Kesler equation of state. The rule suggests using SBV and PG mixing rules for the pseudocritical temperature and pressure computations, respectively, when the reduced temperature is higher than one and the reduced pressure is higher than five; otherwise, the pseudocritical temperature and pressure is calculated according to SBV mixing rule. Comparisons between experimental and calculation data show that the maximum average relative deviation is 1.56% when the mole fraction of CO 2 is less than 50%.

Substrate clogging is regarded as one of the main influencing factors on the sustainable operation in subsurface flow constructed wetlands (SSFCWs). The accumulation of extracellular polymeric substances (EPS) produced by microbial metabolism may contribute to the substrate clogging due to the increasing formation of biofilms in CWs. In this study, the quantity and composition of EPS, and the distribution and variation of bacterial communities in different CW systems with and without aeration and biochar addition were comparatively investigated. Biochar and intermittent aeration addition could shift the production and compositions of EPS in SSFCW. Higher total EPS production was observed in CW with intermittent aeration and biochar (328 mg L−1), compared with control (241 mg L−1), CW with biochar addition (154 mg L−1) and CW with intermittent aeration (285 mg L−1). In addition, biochar addition could decrease the content of soluble EPS (S-EPS), and combination of biochar and aeration could increase the content of tightly B-EPS (TB-EPS). Four fluorescent components were identified in EPS samples by parallel factor (PARAFAC) analysis. The fluorescence intensity of tryptophan-like substance was maximum, followed by tyrosine-like substance and humic acid-like substance. The application of intermittent aeration and biochar improved the abundance of microbes but decreased the diversity of microbes. Moreover, higher relative abundance of some functional bacteria correlated with the nitrogen removal was found in biochar added intermittently aerated SSFCW. The obtained results revealed that intermittent aeration and biochar addition could enhance treatment performance, but might have a potential risk of substrate clogging in SSFCWs.

Little is known about the variations of fresh fruit biomembrane and its physiological and biochemical characteristics during storage. A navel orange mutant 'Gannan No.1' (Citrus sinensis Osbeck) showed higher membrane stability and titratable acid while lower calyx senescence compared with wild-type 'Newhall'. The membrane damage was significantly reduced in 'Gannan No.1' under 10% polyethylene-glycol (41.16% vs. 8.77%) and 30% polyethylene-glycol (52.59% vs.16.11%) treatments on day 45 after harvest. Consistently, membrane electrolyte leakage and malondialdehyde were significantly decreased in 'Gannan No.1', and superoxide dismutase and glutathione reductase were activated. A metabolic analysis was performed to evaluate membrane fatty acid unsaturation and peroxidation. Linolenic acid and hexadecylenic acid contributed to the higher degree of unsaturated fatty acids in 'Gannan No.1'. Furthermore, 'Gannan No.1' accumulated stress-resistant metabolites such as proline, α-tocopherol and glutathione. Correlation analysis of membrane homeostasis indexes with quality parameters showed the importance of biomembrane stability in maintaining citrus fruit quality.

A series of porous hydrogen-bonding covalent organic polymers (HCOPs) have been synthesized based on three-composite building blocks through a quick and succinct method for fluoroquinolone antibiotics adsorption from aqueous solutions. The porous properties of the HCOPs were regulated and controlled by adjusting the lengths of linkers, and the crystallinity and stability were strengthened due to the introduction of hydrogen bonds in HCOPs. Taking advantage of the porous properties and π-conjugated phenyl rings, as well as functional –CO–NH– and –COOH groups, HCOPs removed organic pollutants from wastewater effectively and showed good reusability. The external adsorption behavior was analyzed using both kinetic analysis and isotherm analysis. The results showed that the adsorption obeys the pseudo-second order kinetic model and follows the Langmuir isotherm model. The obtained maximum adsorption capacity of the four HCOPs was arranged in sequence according to the specific surface areas and pore sizes. Furthermore, the internal mechanisms involving perforated porousness, electrostatic interaction, hydrophobic interaction, π–π electron-donor–acceptor (EDA) interaction and hydrogen bonding formation, were investigated in detail. We envisage broadly applying the HCOPs in the facile and effective management of environmental pollution.

Electro-optic modulators (EOMs) are used to change the amplitude and/or phase of the incident light beam by altering the optical properties of a material with an applied voltage. Even though silicon-based EOMs have been demonstrated experimentally, future chip-based optical communication and signal processing technologies require EOMs with a high modulation depth, compact footprint, large bandwidth, low power consumption and cost. In this direction, indium tin oxide (ITO) and graphene have attracted significant attention primarily due to their extraordinary electro-optic properties for the design of such highperformance EOMs.

In this work we showcase two novel examples of electro-optic modulators (EOM) for ultrafast and low-power future transmitters. Unlike weak-interacting EOM design, which often require high feedback in form of high-Q cavity design we deploy novel materials and metal-based approaches. Both devices are based on novel materials, namely Graphene [1] and Indium-Tin-Oxide (ITO) [2], and feature the Silicon-on-Insulator (SOI) platform facilitating ease in monolithic integration (Fig 1).

Liquid petroleum gas (LPG) is a mixture of ethane, propane and heavier hydrocarbons used as a fuel in heating appliancations and vehicles. Due to the composition of LPG, phase transition easier occurs than gas and oil. Therefore, the running parameters of LPG pipelines are different from those of the gas and liquid pipelines. In order to predict the pressure, flow rate and temperature within the network, the network is divided into the node, pipeline element and non-pipe element sub-systems. The mathematical models for each sub-system and the whole network are built. The solution method that unites the network model and physical parameters model is discussed based on the Newton-Raphson method. Finally, the methods are applied to a branching and loop LPG network. The results show the achievements of the paper are valid for steady state simulation of LPG pipeline network.