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Pulmonary tuberculosis (PTB) is caused by Mycobacterium tuberculosis and is one of the most serious diseases worldwide. Circular RNAs (circRNAs) are a large class of non-coding RNAs that were identified with potential regulatory roles in disease pathogenesis and progression. In this study, we used whole transcriptome sequencing to identify circRNAs from 3 PTB patients and 3 healthy individuals to determine the expression pattern of circRNAs in blood and the circRNA molecular regulatory networks in PTB pathogenesis. One hundred and seventy differentially expressed (≥ 2-fold change) circRNAs were dysregulated in PTB, compared with in healthy individuals. Quantitative real-time polymerase chain reaction was used to validate the RNA sequencing analysis from 20 PTB patients, and the results were consistent with the sequencing data. Gene Ontology annotation and Kyoto Encyclopedia of Genes and Genomes pathway analysis were applied to explore the potential circRNA functions of the significantly deregulated genes. Several immunity pathways, including endocytosis pathways in cancer, mitogen-activated protein kinase signaling pathway, human T-lymphotropic virus type 1 infection, and ubiquitin-mediated proteolysis, were involved in PTB pathogenesis. Competing endogenous RNAs (ceRNA) were constructed and inferred that aberrant expression of circRNA-associated ceRNA resulted in extensive variation in gene expression by miRNA-mediated circRNA-mRNA crosstalk interactions. Our study revealed that the circRNA-miRNA-mRNA network may shed light on the biological functions of circRNAs in PTB and provide useful information for exploring potential roles of circRNA in PTB.

In this study, an environmentally friendly approach for surface modification of polymer membrane was reported, which named surface-initiated electrochemically mediated atom transfer radical polymerization (SI-eATRP). It was triggered after diffusion of a CuI/L activator generated at a working electrode. The introduction of electrochemically mediation can control the polymerization of monomers by a one-electron reduction of an initially added air-stable CuII salt. The reaction was carried out in an electrochemical cell with a three-electrode system at low temperature. Using this technique, hydrophilic polymer brushes of poly(N-vinylpyrrolidone) were grafted onto PES membrane surface. The effects of reaction conditions like polymerization time, monomer concentration, initiator amount, and different monomer on the polymerizations of monomer were investigated in detail. Based on these data, we concluded that the polymerization on polymer membrane surface could be controlled by mediating the reaction condition. Moreover, the precisely controlled polymerization may allow it to serve as excellent model systems for polymer membrane modification, in general, to illustrate the role of electrochemically mediating on the polymerization approach. And the water contact angle of the modified membrane decreased from 89° to 72°. The APTT of the modified membrane increased from 46 s to 81 s. Those results indicated that the surface modification by grafting PVP brushes provided practical application for the PES membranes with high surface properties.

A series of poly(ionic liquid)s (PILs) modified polyethersulfone membranes were fabricated via an in-situ cross-linking copolymerization method. Due to the positive charge and ion-exchange properties of the PILs, the membranes showed anion species and strength responsive behaviors. The morphologies and chemical compositions of the membranes were characterized by scanning electron microscope and X-ray photoelectron spectroscopy. The anion species and strength responsive properties were investigated by measuring the fluxes of the membranes with various anion species and concentrations of salt solutions. The anion strength response of the membranes was positive, and the responsive coefficient of the membranes (the ratio of the salt water flux to pure water flux) could reach 26 times when responded to the stimulus of NaCl aqueous solution; the cation species and concentrations had barely influence on the responsive behavior. Meanwhile, the membranes were responded to both anion species (including PF6−, BF4− and SCN-) and their strength: the pure water fluxes and the morphologies of the modified membranes changed associated with different types of anions, and the membranes after ion-exchanging also showed obvious anion strength responsive behaviors to the corresponding salt solutions. The facile design of anion-responsive membranes via in-situ cross-linking polymerization opens up a new route to fabricate “intelligent” membranes for ion-recognizable chemical/biomedical separations and purifications.

In this study, a novel core@shell bead adsorbent was fabricated by using poly (acrylic acid) (PAA) microgels and polyethersulfone (PES) via a facile and versatile strategy for dye uptake from wastewater. PAA microgels were synthesized by distillation precipitation polymerization, followed by enwrapping with PES films to form core@shell beads by a phase inversion technique. The scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) mapping confirmed that the bead had a core@shell structure with PAA microgels in the core and PES on the shell. Batch adsorption experiments indicated that the contact time, initial dye concentration, adsorbent dosage, pH and ionic strength greatly affected the adsorption process. The beads could adsorb methylene blue as high as 84.82 mg/g while the adsorption capacities of methyl violet, rhodamine B, amaranth red and methyl orange were 43.37, 14.60, 2.93 and 2.29 mg/g, respectively. Simultaneously, the beads were recyclable for the removal of dye and the adsorption process fitted well with the non-linear Freundlich isotherm. All the results indicated that the prepared beads were promising in dye treatment.

(Ce x Nd1−x )32.7Fe66.22B1.08 (x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0) ribbons were prepared by melt spinning, and the effect of substitution of Ce for Nd on their microstructure and magnetic properties was investigated. Especially, the phase compositions and microstructures of the ribbons were examined by Mossbauer spectrometry and transmission electron microscopy, respectively. The results indicated that the coercivity (H ci) and remanence (B r) of the ribbons decreased with the increase of Ce content. However, an abnormal increase of H ci was observed in the sample of x = 0.4. This was mainly due to the synergistic effects of the microstructures, the ratio of secondary phases, and the site-preference of rare earth atoms. In this study, the optimal magnetic properties of B r = 6.95 kGs, H ci = 13.65 kOe and (BH)max = 9.56 MGOe were achieved in the (Nd0.6Ce0.4)32.7Fe66.22B1.08 ribbon, which indicated that Ce had a great potential to prepare the low cost and high coercivity magnets.

In this study, polyethersulfone (PES) membranes were modified by in situ cross-linking polymerization of polyurethane with functional groups of –COOH and –SO3H using PEG as the chain extender in one pot, followed with a phase inversion technique. The composite membranes were characterized by FTIR, water contact angle, and scanning electron microscope. Comparing with pristine PES membrane, the modified membranes showed decreased water contact angles and changed cross-sectional morphology. The modified membranes also showed decreased protein adsorption and suppressed platelet adhesion, as well as improved antifouling property. In addition, the composite membranes had prolonged activated partial thromboplastin times due to the functional groups and improved hydrophilicity. The results of contact activation and complement activation also indicated that the modified membranes had good blood compatibility. Furthermore, the cytocompatibility was significantly improved. The highly hemocompatible PES composite membranes fabricated by the in situ cross-linking polymerization of polyurethane may have great potential to be used in the field of blood purification.

In corridor fires, ventilation condition plays an important role on the fire development. Relevant studies have attracted extensive concern, and mainly focused on the effect of opening size on a compartment fire, or on the blockage effect for a tunnel fire. However, the ceiling-jet flow in a corridor under different opening conditions has not been studied. In this paper, the CFD simulation has been carried out to study effect of openings on vertical velocity, which is useful for the theoretical analysis on the smoke layer. Vertical velocity profile in the far-field agreed well with Gauss function. What is more, a small experimental set has been established to carry out the effect of openings on smoke temperature in a confined reduced-scale corridor. By varying the opening size and opening position, while other parameters were fixed, mass loss and temperature field were measured and analyzed, and these data were further applied to compare with the Delichatsios’s model and previous studies.

A new type of thin-walled steel tube/bamboo plywood hollow composite column with binding bars (SBCCB) that used transverse binding bars to reinforce the composite column was developed. The compression performance of 4 specimens with larger slenderness ratio was tested to examine the failure mode of the SBCCBs. The results indicated that the compression failure modes are mainly crushing failure of the bamboo plywood material, partial debonding failure of the adhesion interface and buckling instability failure; the ultimate bearing capacity of the specimens is not only related to net cross-sectional area and slenderness ratio, but also greatly affected due to binding bars. Transverse binding bars can ensure the integrity of the composite column, effectively reduce the debonding failure of the adhesion interface and significantly improve the load-bearing capacity of the SBCCBs.

Based on our recently developed Maxwell iteration for the lattice Boltzmann method, we propose a class of single-node boundary schemes for Dirichlet boundary conditions of the Navier–Stokes equations. The schemes all have second-order accuracy for both straight and curved boundaries. The accuracy and stability of two specific schemes are examined through several numerical experiments. The results validate the second-order accuracy and show that a boundary scheme with a convex combination of distribution functions has better stability.

We report on a self-defensive bilayer hydrogel coating which can switch from a cell adhesion surface to an antibacterial adhesion surface. To covalently attach the coating, an antifouling hydrogel thin film was firstly prepared on a thiol modified substrate as the bottom layer via the thiol–ene click reaction of the ene-functionalized copolymer of poly(sulfobetaine methacrylate-acrylate acid-2-hydroxyethyl methacrylate) (P(SBMA-AA-HEMA)). Thereafter, heparin-mimicking polymer chains were grafted onto the hydrogel film surface as the upper layer via surface initiated atom transfer radical polymerization. The ester group of HEMA was designed as the sensitive part which could be cleaved in a bacterial infectious environment, while the hydroxyl group was designed as the anchoring point of the upper layer. The surface morphology and chemical composition after each modification step were characterized by scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. The bilayer coating could promote cell adhesion and proliferation, as well as bacterial adhesion. After being immersed into a cholesterol esterase solution (simulative bacterial infectious environment), the upper layer could be detached rapidly, and the exposed bottom layer then showed strong resistance to bacteria. Our approach towards bacteria-responsive “intelligent” coating gives new insights into the antibacterial protection of biomedical devices.

To improve the hemocompatibility and antifouling property of polyethersulfone (PES) membranes, heparin-mimicking microgels of poly(acrylic acid-co-N-vinyl-2-pyrrolidone) (P(AA-VP)) and poly(2-acrylamido-2-methylpropanesulfonic acid-co-acrylamide) (P(AMPS-AM)) were synthesized by conventional free radical copolymerization, and then incorporated into a PES matrix by blending. The results of Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and scanning electron microscopy (SEM) confirmed that heparin-mimicking microgels were successfully synthesized. The presence of the microgels in the membrane matrix was also confirmed by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetric analysis (TGA), and SEM. Compared with pristine PES membranes, the improvement of the antifouling property of the heparin-mimicking microgel modified membranes was demonstrated by the increased flux recovery ratio and improved anti-bacterial adhesion, while the enhancement of hemocompatibility for the modified membranes was proved by the decreased plasma protein adsorption, suppressed platelet adhesion, prolonged clotting times, as well as depressed blood-related complement activation. Additionally, after introducing the heparin-mimicking microgels, the membranes showed enhanced cell adhesion and proliferation properties. These results indicated that the heparin-mimicking microgel modified membranes had great potential to be used as blood contacting materials.

We amplified a full-length hepatitis B virus (HBV) genome from the serum of a chronic hepatitis B patient who experienced virological breakthrough with high HBV DNA titer following adefovir (ADV) therapy. The PCR product was cloned and sequencing of the six clones revealed an isolate of C2 subgenotype. Mutation(s) in the polymerase gene responsible for ADV resistance included rtA181T (all clones) and rtN236T (four clones). The rtA181T mutation caused the W172* nonsense mutation in the overlapping S gene. In addition, all the clones harbored another nonsense mutation in the S gene (C69*) and a 207nt in-frame deletion in the preS1 region. These clones were converted to a 1.1mer construct for transient transfection of Huh7 cells. All the clones were deficient in hepatitis B surface antigen production. Three clones had similar levels of DNA replication. Comparison with a wild-type clone of the same genotype revealed a higher intracellular level of replicative DNA for clone c4, which was reduced by putting back the deleted 207nt, but not by co-transfection with an expression construct for the three surface proteins to rescue virion production. The HBcAg expression of the c4 and c4+207nt clones was mainly in the nucleus. Co-transfection with the L/M/S proteins expression construct did not alter the distribution of core. Clone c4 showed a significantly decreased susceptibility to ADV, a mild reduction in susceptibility to lamivudine and tenofovir, but remained sensitive to entecavir. In conclusion, this is an unusual ADV-resistant HBV isolate harboring two nonsense mutations in the S gene and a large in-frame deletion in the preS1 region, but still retains a high replication phenotype, which can provide a platform for recombinant vector construction.

Containers are usually sealed during transportation. When fire occurs in the containers, it is difficult to detect at early stage. In order to understand the fire behavior for different dangerous goods and at different sealing ratio the container door, a series of experiments have been conducted to investigate container fire with different kinds of fuel, heat release rates and sealing ratios varied from 0% to 100%. Both the temperature distributions and the maximum temperature beneath the ceiling of the container have been calculated by the empirical model and compared with the experimental data. Results show that the maximum temperature increases with the sealing ratio due to the heat accumulation inside the container. The temperature along the container ceiling decays exponentially. Moreover, with the consideration of the sealing ratio of container door, a modified model is proposed to predict the maximum temperature beneath the container ceiling, which agree well with the experimental data.

The urban bus service system is one of the most important components of a public transport system. Thus, exploring the spatial configuration of the urban bus service system promotes an understanding of the quality of bus services. Such an understanding is of great importance to urban transport planning and policy making. In this study, we investigated the spatial characteristics of an urban bus service system by using the complex network approach. First, a three-step workflow was developed to collect a bus operating dataset from a public website. Then, we utilized the P-space method to represent the bus service network by connecting all bus stop pairs along each bus line. With the constructed bus network, a set of network analysis indicators were calculated to quantify the role of nodes in the network. A case study of Shenzhen, China was implemented to understand the statistical properties and spatial characteristics of the urban bus network configuration. The empirical findings can provide insights into the statistical laws and distinct convenient areas in a bus service network, and consequently aid in optimizing the allocation of bus stops and routes.

Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a dynamic but reversible disease. We aimed to clarify whether the change in Chinese Group on the Study of Severe Hepatitis B-ACLF (COSSH-ACLF) grade in HBV-ACLF patients can be used to predict prognosis, and to explore the appropriate conditions for performing urgent liver transplantation. We assessed the COSSH-ACLF grades of HBV-ACLF patients at different time points from June 2013 to May 2019 at Huashan Hospital in Shanghai, China, and analyzed the relationship between the change in grade and patient prognosis. A total of 207 HBV-ACLF patients were enrolled, of which 79 underwent urgent liver transplantation. Their COSSH-ACLF grades were calculated at diagnosis, 3–7 days after diagnosis, and on the final day. Most of the final ACLF grades were consistent with their corresponding grades at days 3–7 after diagnosis (62.5%), while only 44.5% were in accordance with the initial grades at diagnosis. In patients who had a poor prognosis (initial ACLF-3 and ACLF-2 or -3 at days 3–7), the 28-day survival rate was 93.3% in those who underwent transplantation and 6.8% in those who did not (P

The genetic association of primary biliary cholangitis with major histocompatibility complex (MHC) has been widely confirmed among different ethnicities. To map specific MHC region variants associated with PBC in a Han Chinese cohort, we imputed HLA antigens and amino acids (AA) in 1126 PBC cases and 1770 healthy control subjects using a Han-MHC reference database. We demonstrate that HLA-DRB1 and/or HLA-DQB1 contributed the strongest signals, and that HLA-DPB1 was a separate independent locus. Regression analyses with classical HLA alleles indicate that HLA-DQB1*03:01 or HLA-DQβ1-Pro55, HLA-DPB1*17:01 or HLA-DPβ1-Asp84 and HLA-DRB1*08:03 could largely explain MHC association with PBC. Forward stepwise regression analyses with HLA amino acid variants localize the major signals to HLA-DRβ1-Ala74, HLA-DQβ1-Pro55 and HLA-DPβ1-Asp84. Electrostatic potential calculations implicated AA variations at HLA-DQβ1 position 55 and HLA-DPβ1 position 84 as critical to peptide binding properties. Furthermore, although several critical Han Chinese AA variants differed from those shown in European populations, the predicted effects on antigen binding are likely to be very similar or identical and underlie the major component of MHC association with PBC.

Wound treatment is a long-lasting clinical issue. Poor angiogenesis leading to delayed wound closure causes huge challenges for healing. Functional electrospun membranes have been established as an efficient strategy to promote wound recovery by protecting and improving vascular regeneration. Here, we aimed to investigate the effect of tazarotene, an active drug for angiogenesis, loaded in aligned electrospun nanofibrous barrier on a soft tissue wound. This aligned membrane was arranged in a single direction, and tazarotene could be released from its nanofibers sustainably. The in vitro study demonstrated that compared with the random drug-loaded or other control groups, the aligned tazarotene-loaded membranes [poly-caprolactone (PCL)/AT] could stimulate proliferation, migration, angiogenesis, and vascular endothelial growth factor secretion and its gene expression of human umbilical vein endothelial cells. Furthermore, the in vivo model showed that the prepared tazarotene-loaded aligned membrane significantly accelerated the speed of healing, improved the neovascularization and re-epithelialization, and inhibited the inflammatory reaction in the wound area. All these results above indicated that the PCL/AT nanofibrous dressing, which could promote angiogenesis because of both stimulation of structure and chemical signals, is a promising wound-caring material.

The prevention of bacteria-induced infections has been increasing in importance in both clinical surgery and biomedical engineering. Although great attention has been paid to designing intelligent antibacterial surfaces, the fabrication processes are still not facile and universal enough, and the antibacterial efficiencies of these surfaces are also not ideal. Herein, ionic liquid (IL) molecules of 3-(12-mercaptododecyl)-1-methyl-1H-imidazol-3-ium bromide (IL(Br)) were synthesized with the minimum inhibitory concentrations as low as 4 and 8 μg mL−1 against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively. By simply immersing a polymeric substrate into the IL(Br) solution, an antibacterial surface with high killing efficiency of 99% against S. aureus (94% against E. coli) was achieved via a mussel-inspired approach. Subsequently, 97% S. aureus and 95% E. coli on the substrate could be released by simple ion-exchange of Br− with (CF3SO2)2N− due to the ion sensitivity of the IL molecular brushes. Thus, the proposed facile strategy towards a superior efficiency surface could be potentially used in intelligent antibacterial fields.

Applications of effective and steady metal catalysts for the hydrogen evolution reaction (HER) via electrolysis of water have a huge potential to relax energy crisis and reduce carbon dioxide emission. Herein, we design a simple, facile, and general approach for the synthesis of a series of transition-metal phosphide nanoparticles embedded in N-doped carbon (NC) nanomaterials using metal salts, abundantly available hexamethylene diamine tetra(methyl phosphonic acid), and urea as precursors. The resultant transition-metal phosphide nanoparticles can serve as high-efficiency and steady HER catalysts. Particularly, when the current density is 10 mA cm-2, the overpotentials of the obtained RhP2@NC are 30, 85, and 70 mV in acid (0.5 M H2SO4), neutral (1 M PBS), and alkaline (1 M KOH) solutions, respectively. Besides, the RhP2@NC exhibits good stability after 10 h in aforementioned solutions. More importantly, it is suited to fabricate other transition-metal phosphide nanoparticles/NC heterostructures by this synthetic strategy. The obtained CoP@NC, FeP@NC, Ni2P@NC, and Cu3P@NC also show relatively high efficiency for HER. Hence, the versatile synthesis strategy opens a new route for the research and fabrication of transition-metal phosphide-based catalysts for HER.

pH-responsive nanocarriers such as polymeric micelles that self-assemble from amphiphilic copolymers containing amino groups have been limited by their significant effects on the blood and thus compromise of their hemocompatibility due to the amino group-induced positive charges. Here we report a biomimetic phosphorylcholine strategy to improve the hemocompatibility of the pH-responsive micelles with positive charges. Amphiphilic copolymers containing different number of tertiary amino groups were synthesized in five steps through ring opening polymerization, azide reaction, thio-bromo “Click” chemistry, and atom transfer radical polymerization to self-assemble biomimetic phosphorylcholine micelles with pH-responsiveness, which shown no significant effects on red blood cells, coagulation, and platelet activation. Moreover, albumin adsorption on the micelles was significantly lower than that of polycaprolactone-methoxypolyethylene glycol (PCL-mPEG) control, and in terms of immune cells, the micelles showed controllable phagocytosis that dependent on the number of tertiary amino groups, in which the one containing four tertiary amino groups in its corresponding copolymer remains had a lower phagocytosis by whole blood leukocyte than that of PCL-mPEG. Based on these results, the hemocompatibility related mechanism of the micelles was discussed and proposed. Our findings demonstrated that this biomimetic phosphorylcholine is a promising strategy to improve the hemocompatibility of the positively charged nanocarriers.

Given the complexity of pollutants in wastewater, development of facile and effective multifunctional materials, which can not only kill bacteria but also remove dyes from wastewater, is in high demand. Herein, a facile strategy for the preparation of positively-charged nanofibrous membranes (NFMs) is reported via the combination of electrospinning and in-situ cross-linked polymerization of poly ([2-(methacryloyloxy)-ethyl] trimethyl ammonium chloride) (PMETAC) in poly (ether sulfone) (PES) solution. The quaternary ammonium salt polymer of PMETAC enabled the NFMs with positive charge to kill bacteria and remove anionic dyes. The antibacterial tests including agar plate counting and live/dead staining indicate that the NFMs show strong antibacterial ability with bacterial killing ratios of nearly 99% for both Escherichia coli and Staphylococcus aureus, as well as remarkable recyclability towards killing bacteria. The dyes adsorption experiments show that the NFMs exhibit high adsorption capacity for anionic dyes up to 208 mg g−1 for Congo Red (CR) and good reusability toward CR. Impressively, the membrane adsorption column test indicates that the CR dye removal ratio is up to 100% for the first time, and that is still as high as 96.5% for the third time with a fresh dye solution. Given the above advantages, such fascinating NFMs may provide new perspectives in the exploitation of multifunctional membrane materials for complex water remediation.

During extracorporeal blood purification, anticoagulants are administered to prevent thrombogenesis. However, haemorrhagic complications owing to near-complete inactivation of blood coagulation and delayed recovery of haemostasis pose serious risks to patients. Here, we show in vitro and in beagle dogs that hydrogel microspheres that adsorb the coagulation factors VIII, IX and XI provide transient blood thinning when placed in the extracorporeal circuit before blood purification. The microspheres inhibited the activities of the coagulation factors by levels (~8-30%) similar to those occurring in mild haemophilia. On its reintroduction into the animal, the purified pseudo-haemophilic blood favoured faster recovery of haemostasis. The transient blood-thinning strategy may increase the safety of clinical blood-purification procedures.

Here, we report the application of mussel-inspired surface coating to prepare heparin-mimetic biomacromolecules modified magnetic Fe

A relaxation-rate formula is presented for the entropic lattice Boltzmann model (ELBM) — a discrete kinetic theory for hydrodynamics. The simple formula not only guarantees the discrete time H-theorem but also gives full consideration to the consistency with hydrodynamics. The relaxation rate calculated with the formula effectively characterizes the drastic changes of the flow fields. By using this formula, the computational cost of the ELBM is significantly reduced and the model now can be efficiently used for a broad range of applications including high Reynolds number flows.

We demonstrate high brightness and efficient light-emitting diodes (QLEDs) with 60-nm-thick double quantum dot light-emitting layers (D-EMLs) based on poly(p-phenylene benzobisoxazole) precursors. This structure distributes the charge balance by blocking electrons. The D-EML QLEDs exhibit significant improvement in brightness, efficiency, and stability. The external quantum efficiency and luminance of D-EML QLEDs show 170% and 48% enhancement compared with a single light-emitting layer, respectively. The efficiency roll-off of D-EML QLEDs is only 16% of that of the S-EML up to 10 V.

This study presents a quantitative analysis and interpretation about the effects of natural air flow, opening size and fire location on flame length in the underground vertical channel like car elevator or staircase. The gas burner of 0.1 × 0.1 m with five heat release rates (HRR) is used and eight locations are considered in 1/7 scale model. The air flow structure inside the vertical channel is investigated by CFD simulation. Hydraulic diameter and a characteristic length is proposed to calculate the flame length. A specific correlation between the flame length and dimensionless HRR is established to estimate the degree of fire disasters in the vertical channel with different opening size and locations.

Microspheres composed of H2SO4-protonated graphitic carbon nitride (g-C3N4) nanosheets were prepared through a template-free dialysis method. The g-C3N4 microspheres displayed a much larger band gap and greater UV light absorption in the light region of 200–300 nm compared with that of bulk g-C3N4, and thus substantially improved their UV light photocatalytic performance towards the degradation of Rhodamine B (RhB). The present work approached soft solution assembly of g-C3N4 nanosheets in a one pot manner, demonstrating a new strategy for constructing g-C3N4 nanostructures.

Flexible sensors based on conductive hydrogels have found potential applications in many emerging electronic devices, but they often suffer from poor mechanical properties, single response mode and low sensitivity. Herein, robust and sensitive pressure/strain sensors are designed and fabricated utilizing novel composite hydrogels composed of hollow polyaniline spheres (HPS), poly(vinyl alcohol) (PVA) and phytic acid (PA). By taking advantages of structure-derived elasticity of hollow spheres, conductivity of doped conducting polymers, flexibility of polymer matrix and physically cross-linked structure, the composite hydrogels exhibit outstanding mechanical properties, strain sensitivity, piezoresistivity and solution processability. The optimized composite hydrogel possesses high tensile strength (9.3 MPa), stretchability (>493%) and toughness (2.6 MJ/m3). Resistive-type strain sensors assembled from the composite hydrogel can achieve a gauge factor (GF) of 2.9 in the strain range of 0%~300%, a GF of 7.4 in the strain range of 300%–450%, a response time of 0.22 s and high reliability (1000 cycles). Capacitive-type pressure sensor with ultrahigh sensitivity of GF = 3.6 kPa−1 is fabricated by sandwiching a dielectric layer between two composite hydrogel films. Interestingly, piezoresistivity of such composite hydrogels makes them promising materials for piezoresistive-type pressure sensors and visualization of pressure. On the basis of their high performances, flexible sensors of the composite hydrogels are applied in monitoring various human motions, physiological activities and bending/vibration deformations in daily life.

In this paper, we develop a high order finite difference boundary treatment method for the implicit-explicit (IMEX) Runge-Kutta (RK) schemes solving hyperbolic systems with possibly stiff source terms on a Cartesian mesh. The main challenge is how to obtain the solutions at ghost points resulting from the wide stencil of the interior high order scheme. We address this problem by combining the idea of using the RK schemes at the boundary and an inverse Lax-Wendroff (ILW) procedure in [29] , [30] . Specifically, we only apply the ILW procedure in the starting stage of the RK method. In the intermediate stages, we solve out the intermediate solutions as well as their first-order spatial derivatives at the boundary by using the RK schemes, which are then used to compute solutions at ghost points by Taylor expansions. Our method is different from the widely used approach for the explicit RK schemes by imposing boundary conditions at intermediate stages [14] , [29] , [30] which does not apply to IMEX schemes. In addition, the intermediate boundary conditions are available for explicit RK schemes only up to third order while our method applies to IMEX and explicit RK schemes of arbitrary order. The stability and the desired accuracy of our boundary treatment with IMEX RK method up to fourth order are demonstrated numerically through 1D examples and 2D reactive Euler equations.

Polyethersulfone (PES) and its derivatives are chemical resistant, thermally stable and excellent processable, which have been widely used in filtration and hemodialysis fields. However, the hydrophobicity and bioinert of pristine PES limit the application in hemodialysis. In this study, PES derivatives were successfully prepared in homogeneous phase system via gamma irradiation polymerization of sodium styrene sulfonate (SSS), acrylic acid (AA) and N-pyrrolidone (NVP). The obtained derivatives of PES-g-SSS, PES-g-NVP, PES-g-AA/SSS, PES-g-NVP/SSS, and PES-g-AA/NVP/SSS could be directly used to prepare membranes using dimethylacetamide as solvent by phase inversion method. Then, Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), water contact angle, and surface zeta potential analyses were used to characterize the structure of modified PES membranes. The results of ultrafiltration experiment showed that the water flux increased 104.4% for PES-g-AA/SSS and 103.7% for PES-g-AA/NVP/SSS compared with the pristine PES. Moreover, the contact angle, protein adsorption and platelet adhesion decreased in all modified membranes, especially the PES-g-AA/NVP/SSS membrane has no platelet adhesion at all. The hemocompatibility of the membranes was further tested by complement activation, clotting time and hemolysis ratio, which showed the modified membranes have good hemocompatibility. The proposed one-step radiation-induced homogeneous polymerization approach opens a new route to fabricate advanced PES derivatives as blood-contacting materials.

A novel ion species-responsive oil-water separation material was designed: poly ionic liquid (PIL) was carried on the graphene oxide (GO) by free radical polymerization, then the PIL modified GO sheets (GO-PIL) were coated on cotton fabric (CF). The wettability of the obtained GO-PIL coated CF (GO-PIL@CF) could be switched between hydrophilic and hydrophobic state with the exchange of different types of counteranions. Water contact angle of the GO-PIL@CF could be switched between 0 to about 145°; and correspondingly the underwater oil contact angle would change between about 148 to 0°. Because of the switchable wettability, the GO-PIL@CF could selectively separate water or oil from the oil-water mixtures. Meanwhile, due to the loose fibrous structure, the GO-PIL@CF showed relatively high permeate fluxes; in the hydrophilic state the water flux was about 36000 L/m2h, while in the hydrophobic state the fluxes for the low-density oils (n-hexane and toluene) were about 59,000 and 65000 L/m2h, respectively. Consequently, the separation processes could be completed simply by gravity. In addition, because of the soft and flexible mechanical property, the GO-PIL@CF could serve as wrappage of traditional absorbents and be applied directly as absorbent to remove water or oil selectively from their mixtures.

Scale criterion has been proposed for tunnel fires, however, some parameters are usually not feasible to be implemented. In this study, numerical and experimental simulations have been performed to validate the scale criterion. First, the wall thickness parameter was studied since it plays an important role in the heat conduction. The results of the simulations were compared with Hu’s full-scale experimental data. Then, the other ambient temperature and wall materials parameters were investigated through the numerical simulations. Furthermore, a series of experiments were conducted in two reduced-scale tunnel tables. The simulation results showed that when the ambient temperature varied with the scale criterion, the decay speed of the dimensionless smoke temperature for the 1/18 scale becomes a little smaller. Experimental results showed that the decay speed of dimensionless temperature rises if both the asbestos and steel board was smaller. However, the decay speed in the cases of steel boards was larger than that of the simulation results. Moreover, when the aluminum silicate board was used as the wall material, the results of numerical simulations agreed well with experiments in the near-field. But when x/H > 4, the decay speed of dimensionless temperature rise for experiments was larger than numerical simulations.

A recyclable and regenerable magnetic polysaccharide absorbent for methylene blue (MB) removal was prepared by coating magnetic polyethyleneimine nanoparticles (PEI@MNPs) with sulfonated chitosan (SCS) and further cross-linked with glutaraldehyde. The driving force for coating is the electrostactic interaction between positively charged PEI and negatively charged SCS. Infrared spectra, zeta potential, thermal gravimetric analysis and X-ray diffraction demonstrated the successful synthesis of magnetic polysaccharide absorbent. The self-assembly of polysaccharide with magnetic nanopartices did not alter the saturation magnetization value of the absorbent confirmed by vibrating sample magnetometer. The nanoparticles showed fast removal (about 30min reached equilibrium) of MB. In particular, the removal ability of MB after desorption did not reduce, demonstrating an excellent regeneration ability. Our study provides new insights into utilizing polysaccharides for environmental remediation and creating advanced magnetic materials for various promising applications.

A thin-walled steel tube/bamboo plywood composite hollow column with binding bars (SBCCB) was developed using transverse binding bars to reinforce a thin-walled steel tube and bamboo plywood composite hollow column. Low reversed cyclic loading tests were performed on 9 SBCCB specimens to observe the damage process and morphology in the SBCCBs. The effects of the slenderness ratio, the net cross-sectional area of the bamboo plywood, the assembly patterns of the cross sections, and the binding bars on the stress and seismic performance were investigated. The results show that the main failure modes of the SBCCBs were cracking of different adhesion interfaces at the base of the column and fracturing of the bamboo plywood. The cross-sectional assembly pattern has a significant effect on the failure modes; increasing the cross-sectional area and the slenderness ratio of the composite column will dramatically improve the seismic performance of the SBCCBs. SBCCBs have excellent elastic deformation and seismic energy consumption characteristics. The binding bars ensure the integrity of the specimen and inhibit the failure of the adhesion interface at the base of the column. Finally, based on the measurement of the axial pressure and the stress-strain curve within elastic range of the composite columns, a simplified mechanical model and a calculation method for bearing capacity was formulated. The calculation values of bearing capacity agree well with the experimental ones, and calculation method can be used to provide guidance for engineering applications of a SBCCB.

A universal mold casting approach for the preparation of cation-exchange membranes (CEMs) and anion-exchange membranes (AEMs) with ultrahigh ion-exchange capacities (IECs) is developed based on in situ cross-linking polymerization of acrylic acid (AA) and 2-vinylpyridine (2VP), respectively. This new method produced ultrahigh IECs of 7.88 mequiv g–1 for CEM and 6.27 mequiv g–1 for AEM, which are 8.8 and 7.0 times that (0.89 mequiv g–1) of Nafion 117, respectively. Also, the prepared membranes demonstrate excellent thermal and chemical stability and acceptable conductivity. As a consequence, the membranes show relatively high performance for ion-exchange application and methanol barrier, exhibiting ion permeabilities of 2.06 × 10–7 cm2 s–1 for Na+, 2.57 × 10–7 cm2 s–1 for Ca2+, 1.45 × 10–7 cm2 s–1 for Cu2+ regarding CEMs, and 7.72 × 10–7 cm2 s–1 for methanol regarding AEMs. These results indicate that the CEMs and AEMs fabricated from the universal mold casting approach are promising candidates for targeti...

Thin-walled steel tube/bamboo-plywood composite hollow columns (SBCCs) have excellent physical and mechanical properties. The simple cross section of this composite makes it simple to process and suitable for industrial production. In this paper, axial and eccentric compression tests were conducted on 21 specimens to study the failure characteristics and maximum bearing capacity of this composite. The test results showed that compressive failure in an SBCC is primarily characterized by damage from glue failure at the matrix interface at the end of the column, internal damage of the bamboo-plywood material, damage from glue failure on the tension side in the middle of the column, and buckling damage to the plywood material on the compressive side. The overall adhesive strength between the matrixes primarily determined the failure mode. The maximum bearing capacity of the SBCC generally increased with the net cross-sectional area of the bamboo and decreased with the slenderness ratio and eccentricity. The hollow ratio reduced the slenderness ratio of the test specimens with the same net cross-sectional area of the bamboo and increased the critical compressive load, which significantly improved the compressive load capacity, as was reflected in the slenderness ratio. Finally, a model was formulated based on a non-linear regression analysis of the experimental data. The model was used to determine the allowable compressive capacity of an SBCC to provide guidance for engineering applications.

A facile method to construct reversible thermoresponsive switching for bacteria killing and detachment was currently developed by host-guest self-assembly of β-cyclodextrin (β-CD) and adamantane (Ad). Ad-terminated poly(N-isopropylacrylamide) (Ad-PNIPAM) and Ad-terminated poly[2-(methacryloyloxy)ethyl]trimethylammonium chloride (Ad-PMT) were synthesized via atom transfer radical polymerization, and then assembled onto the surface of β-CD grafted silicon wafer (SW-CD) by simply immersing SW-CD into a mixed solution of Ad-PNIPAM and Ad-PMT, thus forming a thermoresponsive surface (SW-PNIPAM/PMT). Atomic force microscopy (AFM), X-ray photoelectron spectrometry (XPS), and water contact angle (WCA) analysis were used to characterize the surface of SW-PNIPAM/PMT. The thermoresponsive bacteria killing and detachment switch of the SW-PNIPAM/PMT was investigated against Staphyloccocus aureus. The microbiological experiments confirmed the efficient bacteria killing and detachment switch across the lower critical solution temperature (LCST) of PNIPAM. Above the LCST, the Ad-PNIPAM chains on the SW-PNIPAM/PMT surface were collapsed to expose Ad-PMT chains, and then the exposed Ad-PMT would kill the attached bacteria. While below the LCST, the previously collapsed Ad-PNIPAM chains became more hydrophilic and swelled to cover the Ad-PMT chains, leading to the detachment of bacterial debris. Besides, the proposed method to fabricate stimuli-responsive surfaces with reversible switches for bacteria killing and detachment is facile and efficient, which creates a new route to extend the application of such smart surfaces in the fields requiring long-term antimicrobial treatment.

The chemical compositions are very important for designing blood-contacting membranes with good antifouling property and blood compatibility. In this study, we propose a method combining ATRP and click chemistry to introduce zwitterionic polymer of poly(sulfobetaine methacrylate) (PSBMA), negatively charged polymers of poly(sodium methacrylate) (PNaMAA) and/or poly(sodium p-styrene sulfonate) (PNaSS), to improve the antifouling property and blood compatibility of polysulfone (PSf) membranes. Attenuated total reflectance-Fourier transform infrared spectra, X-ray photoelectron spectroscopy and water contact angle results confirmed the successful grafting of the functional polymers. The antifouling property and blood compatibility of the modified membranes were systematically investigated. The zwitterionic polymer (PSBMA) grafted membranes showed good resistance to protein adsorption and bacterial adhesion; the negatively charged polymer (PNaSS or PNaMAA) grafted membranes showed improved blood compatibility, especially the anticoagulant property. Moreover, the PSBMA/PNaMAA modified membrane showed both antifouling property and anticoagulant property, and exhibited a synergistic effect in inhibiting blood coagulation. The functionalization of membrane surfaces by a combination of ATRP and click chemistry is demonstrated as an effective route to improve the antifouling property and blood compatibility of membranes in blood-contact.

Seismic ductility reduction factors for flexural-type structures with vertical irregularities subjected to pulse-like and non-pulse-like ground motions are investigated in this paper. By establishing various multi-node flexural cantilever-column models, the ductility reduction factor of vertically irregular structures is studied by modifying the ductility reduction factor of irregular structures. The effects of various factors such as ductility level, irregular ratio and pulse-like earthquake excitation on modification coefficient are also explored. The analysis results reveal that: 1) the modification coefficient decreases with smaller irregularity ratio; 2) ductility reduction factors for vertically irregular structures are significantly smaller than those of regular structures; 3) ductility level exerts a certain influence on ductility reduction factor without an obvious trend; and 4) the modification coefficient under pulse-like excitation is smaller than those from non-pulse-like motions and the influence of pulse-like earthquake is coupled with irregularity ratio. This paper concludes with the statistical outcomes based on average of results and recommends modified factors for practice uses.

The complex synthesis through multistep reactions and tedious purifications based on different monomers or macromolecules limits the practical applications of functional polymers. Herein, a facile approach toward a series of functional polyurethanes (PUs) is designed for versatile biological applications within fewer step reactions under mild conditions. The tertiary amino groups in the PU are converted into zwitterions or quaternary ammonium salt via simple one-step synthesis, and then used to prepare PU/polyethersulfone composite membranes. The composite membrane with tertiary amine groups exhibits significant adsorption capability to anionic dye Congo red (CR) and toxin bilirubin. The membrane bearing zwitterionic PU displays excellent blood compatibility; while which with quaternary ammonium salts has antibacterial property. Furthermore, carboxybetaine-functional composite membrane is exploited to bear Ag nanoparticles to endow with dual functions of antibacterial and antifouling properties. This work demonstrates the potential of PUs as readily available, multi-functional, and easy-to-use materials for biological applications.

In this study, poly(sodium p-styrenesulfonate)/poly(methyl methacrylate) particles were facilely prepared by in situ cross-linked polymerization followed with a liquid–liquid phase inversion technique. The particles exhibited selective adsorption for cationic dyes due to the negatively charged sulfonic groups. The intra-particle diffusion process was the rate-limiting step for the adsorption of methylene blue. More than 90% of cationic dye was removed by the adsorption column of the particles after three circulations. The particles could be facilely fabricated and industrially used for wastewater treatment.

Graphene oxide (GO), a graphene nanomaterial with great application potential, possesses promising adsorption abilities towards various water contaminants due to the ultra-large surface area and the nature of electric charge on the surface. However, ultrahigh centrifugation for a prolonged time is strongly needed to collect the highly dispersed GO in the recovery process. In this study, a GO-based polymeric composite particle with core–shell structure was fabricated by a facile method. Polyethersulfone (PES) was chosen as the shell to enwrap GO through a liquid–liquid phase inversion process, since the PES shell presented high porosity, good mechanical property and easily modified ability. Methylene blue (MB), a cationic dye, was chosen as the adsorbate to investigate the adsorption capabilities, kinetics and isotherms of the prepared particles. The PES@GO core–shell particles displayed an adsorption capacity as high as 352.11 mg g−1 for MB dye, and the adsorption rates could be improved by modifying the PES shells with hydrophilic fillers. The MB adsorption behavior fitted the pseudo-second-order kinetic model and the Langmuir isotherm very well, and the adsorption process was controlled by the intra-particle diffusion. In addition, a particle column was used to further study the removal ability of environmental toxins, and the results revealed that the composite particles had great potential to remove cationic dyes for wastewater treatment on an industrial scale.

Surface molecular imprinting for proteins is an emerging cross-field of molecular imprinting engineering and functional materials. In this contribution, we report a novel design of magnetic two-dimensional molecularly imprinted polymers (2D-MIPs) for the high recognition and separation of proteins. Bovine serum albumin-surface-imprinted polydopamines were prepared on the surfaces of the magnetic Fe3O4-graphene oxide hybrid to form magnetic 2D-MIPs for proteins. The 2D Fe3O4-graphene oxide substrate possesses a dominant surface-to-volume ratio in comparison to 3D spherical substrates with the same volume. These materials are sensitive to a magnetic field and can be easily separated using an external magnet. The binding experimental results of bovine serum albumin on magnetic 2D-MIPs and real sample analysis demonstrated the high recognition specificity, selectivity, accessibility and convenient separation of 2D-MIPs for template protein. The design and synthesis of magnetic 2D-MIPs provide a new perspective for the surface molecularly imprinted materials with potential in the recognition and separation of proteins.

Self-alignment of thermally reduced graphene sheets (TRG) that enable highly efficient heat transfer paths in their poly(p-phenylene benzobisoxazole) (PBO)-based nanocomposite films along the in-plane direction was achieved for the first time without any assistance of an external magnetic or an electric field. In the in-plane direction, the nanocomposite films possess an ultra-high thermal diffusivity (900-1000 mm2 s-1) and a thermal conductivity (50 W m-1 K-1) with a TRG concentration