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Satellite clock bias is the key factor affecting the accuracy of the single point positioning of a global navigation satellite system. The traditional model back propagation (BP) neural network is prone to local optimum problems. This paper presents a prediction model and algorithm for the clock bias of the BP neural network based on the optimization of the mind evolutionary algorithm (MEA), which is used to optimize the initial weights and thresholds of the BP neural network. The accuracy of the comparison between clock bias data is verified with and without one-time difference processing. Compared with grey model (GM (1,1)) and BP neural network, this paper discusses the advantages and general applicability of this method from different constellation satellites, different atomic clock type satellites, and the amount of modeling data. The accuracy of the grey model (GM(1,1)), BP, and MEA-BP models for satellite clock bias prediction is analyzed and the root mean square error, range difference error, and the mean of the clock bias data compared. The results demonstrate that the prediction accuracy of the three satellites significantly increased after one-time difference processing and that they have good stability. The prediction accuracy of four sessions of 2 h, 3 h, 6 h, and 12 h obtained using the MEA-BP model was better than 0.74, 0.80, 1.12, and 0.87 ns, respectively. The MEA-BP model has a specific degree of improvement in the prediction accuracy of the different sessions. Additionally, the prediction accuracy of different models has a specific relationship with the length of the original modeling sequence, of which BP model is the most affected, and MEABP is relatively less affected by the length of the modeling sequence, indicating that the MEA-BP model has strong anti-interference ability. [ABSTRACT FROM AUTHOR]

Summary: There is no large data analysis reporting the outcome of Chinese kidney transplant patients using mycophenolate mofetil (MMF). This study analyzed 6719 patients from the Chinese Scientific Registry of Kidney Transplantation using MMF, which included 1153 from donation after cardiac death (DCD), 1271 from donation after brain and cardiac death (DBCD), and 4295 from living donor (LD). Compared with the transplants from deceased donor (DD), better outcomes including 3‐year graft survival probabilities (LD = 95.8% vs. DD = 91.3%), incidence of delayed graft function (DGF, LD = 2.4% vs. DD = 17.7%), infection (LD = 10.7% vs. DD = 20.7%), graft loss (LD = 2.3% vs. DD = 6.3), and death (LD = 1.3% vs. DD = 3.2%) were shown in the LD group, with similar incidences of acute rejection (AR, LD = 3.7% vs. DD = 4.7%), hyperuricemia (LD = 21.7% vs. DD = 22.2%) within postoperative 1 year, and serum creatinine (Scr) >133 μmol/l at 1 year (LD = 18.8% vs. DD = 18.6%). Nonsignificant differences were found between the DCD and DBCD group. The 5‐year survival of patient and graft in the LD group were 97.5% and 93.0%. Adjusted Cox model for graft loss showed significant associations with DGF [hazard ratio 3.7 (95% CI: 2.4, 5.8)], AR [2.8 (1.7, 4.6)], Scr >133 μmol/l at 1 year [2.6 (1.5, 4.2)], hyperuricemia [2.3 (1.6, 3.3)], and DD [1.6 (1.1, 2.4)]. [ABSTRACT FROM AUTHOR]

TiO 2 is one of the wonder materials that possess extraordinary engineering versatility in terms of nanostructures, shapes and morphology. TiO 2 nanomaterials have shown superior antibacterial capability, it is however still unclear about the intrinsic dimensional effects on antibacterial mechanisms. This study reported a fundamental antibacterial mechanism about the intrinsic antibacterial capabilities of the engineered nanostructured TiO 2 materials (ENMs) – from three aspects 1) the structures of such nanoparticles, rods, tubes, fibres and spheres; 2) sizes/diameters/length of the ENMs; 3) combined effect due to dimensions and structures. Experimental results revealed that, the 1 D nanotubular TiO 2 , being the smallest individual ENMs possessed the highest toxicity towards E. coli; further studies showed that 3 D dendritic nanostructure incorporated with 1 D ultrathin TiO 2 nanorods had the highest antibacterial efficiency. Comparative studies have suggested that, the well-engineered 3 D TiO 2 nanomaterials (microspheres) with enhanced surface properties such as evenly grown 1 D sub-structures were more aggressive than the cluster aggregated 1D nanomaterials. In-depth research concluded that with well-controlled nanorods density and length, the integrated 3 D ENMs exhibited most efficient antibacterial activities. Such results could benefit the future antibacterial applications and the agent fabrications. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) was compounded with β-nucleating agent and injection-molded at 180 °C or 220 °C. The samples were subsequently treated by supercritical carbon dioxide (scCO 2 ) at different temperatures. Results show that processing temperature and scCO 2 treatment could strongly influence the tensile and impact properties of β-nucleated PP. In particular, the sample processed at 220 °C and treated at 120 °C exhibit much enhanced impact strength (4.8 times that of its untreated counterpart). FTIR, WAXD, SEM and DMA were performed to explore the effects of processing temperature and scCO 2 treatment on structure of the samples. Deformation-induced plastic flow and micro-voids were also evaluated to construct structure-property relations. It was found that the influence of processing temperature on mechanical properties is mainly associated with the β-form content and β-crystalline morphology, while the structural changes in the crystalline lamellar scale may be responsible for the toughening effect of scCO 2 treatment. [ABSTRACT FROM AUTHOR]

In order to realize the ideal water treatment in a green and energy saving manner, TiO 2 based multifunctional membrane proved to be a promising approach owing to its capability in utilizing visible light for photocatalytic pollutant degradation and disinfection of bacteria. However, few studies were found about the investigation of antibacterial abilities arising from the intrinsic properties of membrane and its minor composition. Here, a multifunctional membrane was created via a green approach to integrate the merits of hierarchical Ag/AgBr/TNF composites with micro-/-nano porous structures, the intrinsic antibacterial abilities of Ag, and the visible light absorption capability of AgBr. The synergy effects made it being a promising multifunctional membrane for concurrent water filtration and disinfection in a sustainable way. Through a versatile characterization techniques of FESEM, XRD, TES, XPS, and UV-vis spectrometer, the morphology, structure and surface properties of the well prepared Ag/AgBr/TNF multifunctional membrane was thoroughly studied to reveal the deep mechanism behind the high flux, high photocatalytic degradation and disinfection efficiency under visible light. It indicates that the Ag/AgBr/TNF multifunctional membrane exhibited better photocatalytic activity, higher water permeate flux, and higher disinfection abilities over commercial P25 membrane under visible light. Besides the deep mechanism elaborated, the key factors in terms of predominant oxidative species was also exploited in details. This further solidify the broad future of the developed multifunctional membrane. In view of the roaring demand of advanced water treatment and disinfection technology, it is reasonable to believe our developed visible light responsive Ag/AgBr/TNF multifunctional membrane will show great significances to a green and clean future. [ABSTRACT FROM AUTHOR]

Heterojunctioned architectures were facilely fabricated using hydrothermally treated electrospun TiO 2 nanofibers in an alkaline Sr(NO 3 ) 2 precursor solution in an electronic oven. TiO 2 on the fiber surface was partially dissolved into Ti 4+ to react with Sr 2+ in favor of the nucleation of SrTiO 3 on TiO 2 nanofibers, and thus a heterojunction was formed between SrTiO 3 and TiO 2 , which will benefit the improvement of photocatalytic activity. And then a multifunctional membrane was created by functionalizing the surface of commercial cellulose acetate (CA) membrane with heterojunctioned SrTiO 3 /TiO 2 nanofibers. This newly structured membrane exhibited excellent water purification performances in a concurrent photocatalytic membrane filtration system under the irradiation of UV light, because it is able to integrate the advantages of photocatalysis and membrane filtration while minimizes their disadvantages. The high water purification performances in terms of high photodegradation ability and high permeate flux are attributed to the high photocatalytic activity of heterojunctioned SrTiO 3 /TiO 2 nanofibers architectures and their structured porous functional layer favorable for fast water pass through. [ABSTRACT FROM AUTHOR]

In this work, influence of matrix crystallization on the electrical conductivity and mechanical properties of poly( l -lactide)/multiwalled carbon nanotubes (PLLA/MWCNTs) nanocomposites has been investigated. By introducing trace amount of nucleating agent (0.15 wt%) and controlling isothermal crystallization time (0.1–8 min) of PLLA matrix in a hot mould (130 °C), the injection molded bars of the nanocomposites with different matrix crystallinities (5–45%) were prepared. Interestingly, the electrical conductivity is found to be linearly increased with increasing matrix crystallinity for nanocomposites with low concentrations of MWCNTs (below the percolation threshold). This could be attributed to the volume exclusion effect and the straightening effect of MWCNTs provided by PLLA crystallization, as evidenced from SEM observations. However, matrix crystallization induced reconstruction of MWCNTs network cannot effectively enhance the electrical conductivity when the concentration of MWCNTs is high enough (above the percolation threshold). More interestingly, the reconstructed MWCNTs network shows a better reinforcement effect in the nanocomposites as compared with that initially formed in the amorphous matrix. [ABSTRACT FROM AUTHOR]

Highlights: [•] Novel-structured TiO2/CuO composite nanofibers was optimized for H2 generation. [ • ] Vivid changes of physicochemical properties influenced by calcinations temperature. [ • ] Significance of physicochemical properties synergy on H2 generation was revealed. [ • ] The optimized photocatalyst exhibited the highest H2 generation activity. [ • ] Reusable and stable with negligible Cu leaching. [Copyright &y& Elsevier]

Using electrospinning, specially prepared Ti and Sr precursor TiO2/ SrTiO3 composite nanofibers were successfully fabricated. This would ensure the close and uniform contact between TiO2 and SrTiO3, which significantly contributes to the electrons transfer at the interface between the two semiconductors with different band gaps. Meanwhile, the long fibrous structure of TiO2/ SrTiO3 composite nanofibers would further ease the electron transfer, enlarge the specific surface area, and enhance the light absorption capability thus leading to the improvement of photocatalytic efficiency. Because of the above-mentioned advantages, the TiO2/ SrTiO3 composite nanofibers exhibited higher photocatalytic H2 generation efficiency over bare TiO2 nanofibers in a water/methanol sacrificial reagent system under the irradiation of UV light. [ABSTRACT FROM AUTHOR]

Abstract: Here, hierarchically meso/nanoporous TiO2 was successfully fabricated by a facile and efficient hydrolysis and calcination method using Ti(OC4H9)4 and K2S2O8 as precursors. The hydrosol was firstly prepared by drop-wise adding ethanol dissolved Ti(OC4H9)4 solution into acetone dissolved K2S2O8 solution under a vigorous stirring and heating condition. After being sufficiently hydrolyzed, the hydrosol was calcined to promote the crystallization of TiO2 and successfully dope S and C on TiO2. The calcination temperature significantly affects the doping of S and C on TiO2, crystallization of TiO2, formation of hierarchically meso/nanoporous structure of TiO2 and its light absorption capability. The S- and C-codoped TiO2 exhibits high photocatalytic H2 generation efficiency in a water/methanol sacrificial reagent system under the irradiation of UV light. The high photocatalytic efficiency is dependent on the comprehensively competing effects of the codoping of S and C, crystallization, specific surface area and light absorption capability. The S- and C-codoped TiO2 calcined at 600°C demonstrates the highest photocatalytic H2 generation efficiency, which is ascribed to the balanced synergy of the abovementioned factors. [Copyright &y& Elsevier]

Abstract: The effect of fabrication method on the properties of hierarchical 3D TiO2 nanostructures was investigated by employing and developing both hydrothermal method and calcination method to synthesize hierarchical 3D TiO2 nanorod spheres in this study. A comprehensive comparison in terms of morphologies, crystallization, specific surface areas, light absorption capabilities, and photoluminescence spectrum was conducted between 3D TiO2 nanorod spheres synthesized via hydrothermal method and that synthesized via calcination method. A better photocatalytic activity was demonstrated over the TiO2 nanorod spheres synthesized through calcination method. This was ascribed to the better crystallization and monodispersion of the hierarchical 3D TiO2 nanorod spheres resulted from the calcination method; thus rendering it with more superior characteristics such as larger specific surface area, enhanced light absorption capability and faster transfer of electrons which suppress the recombination of photogenerated electrons and holes. This study is thus significant not only in promoting the development of hierarchical 3D TiO2 nanorod spheres via different methods, but also in revealing the effect of fabrication method on the photocatalytic activity of hierarchical 3D TiO2 nanorod spheres. The calcination method is proposed to be a facile and promising method for scale-up production of the hierarchical 3D TiO2 nanorod spheres with high photocatalytic activity for efficient pollutants degradation. [Copyright &y& Elsevier]

Abstract: To counter the global water crisis such as water resources scarcity and water quality deterioration, membrane filtration has been widely used as a promising technology. Recently, nano-materials and its structured membranes demonstrated multifunctional water purification capability in terms of decontamination and disinfection. Here, hierarchical nitrogen (N)-doped “nut-like” ZnO nanostructured material was hydrothermally synthesized at large scale. This hierarchical N-doped “nut-like” ZnO nanostructured material was well characterized and successfully assembled on a piece of polymer membrane surface to create a multifunctional membrane. This newly developed membrane demonstrated high pollutants removal ability via rejection and photodegradation, and strong antibacterial growth ability under visible light irradiation. At the same time, this novel membrane holds the potential to produce clean water at a constant high flux. The experimental results indicated that the hierarchical N-doped ZnO “nut-like” nanostructured material enhanced the photocatalytic activity in a comparison to commercial ZnO powder. This is caused by enlarging the specific surface area and enhancing the light utilization rate. It is reasonable to believe this hierarchical N-doped “nut-like” ZnO nanostructured membrane would benefit the water purification field. [Copyright &y& Elsevier]

Abstract: Through hydrothermally growing SrTiO3 cubics on the surface of electrospun TiO2 nanofibers, SrTiO3/TiO2 nanofibers heterostructures were successfully fabricated in the present study. This process is able to ensure uniform distribution of SrTiO3 on the surface of TiO2 nanofibers and lead to close contact between SrTiO3 and TiO2, which is beneficial for the fast separation of photogenerated electrons and holes so as to suppress the recombination of photogenerated electrons and holes at the interphase of SrTiO3 and TiO2. Besides this, the long 1D fibrous structure easy for electron transfer, the hierarchical structure promoting mass transfer and allowing more light reflection and absorption, and the large specific surface area providing more reactions sites to facilitate the reactants to desired oxidation places all together create a synergistic effect on improving the photocatalytic activity of the hierarchical SrTiO3/TiO2 nanofibers heterostructures. Under the irradiation of UV light, in a water/methanol sacrificial reagent system, the SrTiO3/TiO2 nanofibers heterostructures generate five times more H2 than bare TiO2 nanofibers because of its high photocatalytic activity. [Copyright &y& Elsevier]

Abstract: Currently, the biggest challenge for filtration membrane application is the severe membrane fouling problem, which consequently results in low flux and high energy cost. Herein, a novel kind of multifunctional membrane was fabricated via integrating the advantages of conventional polymer membrane as supporting layer and “forest” like hierarchically structured TiO2/ZnO nanomaterials as functional layer. This membrane has shown multifunctional properties, such as, high photocatalytic activity, high flux and high antibacterial capacity, which make it as a good candidate to tackle the challenge of producing clean water at a constant high flux with no membrane fouling problem and energy saving manner. The outstanding performance of this novel membrane would bring enough benefits to filtration membrane industry for clean water production and environmental protection. [Copyright &y& Elsevier]

Abstract: Hierarchical porous TiO2 hollow microspheres were synthesized by a facile approach from a one-step template method. This novel approach avoids tedious multiple steps from conventional template method for fabricating hierarchical porous and hollow microspheres. The as-prepared microspheres were characterized by XRD, SEM, TEM, nitrogen adsorption, and UV–vis DRS. Its photocatalytic activity was demonstrated in the photocatalytic degradation of Rhodamine B. Structural characterization indicates that the as-prepared microspheres had a hollow interior and a hierarchical porous structure with both large and small mesopores on its surface. The average diameters and BET surface areas of the hierarchical porous TiO2 hollow microspheres were 1.5μm and 117m2/g, respectively. Optical adsorption investigation shows that the hierarchical porous TiO2 hollow microspheres possessed the optical band gap of 3.42eV. A possible formation mechanism for the hierarchical porous TiO2 hollow microspheres was discussed. The hierarchical porous TiO2 hollow microspheres exhibited much higher photocatalytic activity than the commercial P25 TiO2. In addition, the as-prepared microspheres can be easily recycling for reuse. All these advantages show a bright future for this microspheric photocatalyst in environmental purification. [Copyright &y& Elsevier]

In this study, bismuth/titanium oxide (Bi3+/TiO 2) composite nanofibers (herein after referred to as Bi/TiO 2) with enhanced physicochemical properties thus photocatalytic efficiency are successfully synthesized via electrospinning which maximizes the uniformity of Bi and Ti at molecular level. Bi/TiO 2 shows positive characterization through anatase crystallinity, large light utilization rate, high specific surface area and low electron holes pair recombination rate as a result of the novel materials synthesis approach. Glycerol as a typical pollutant of industrial wastewater, is used here to demonstrate the concurrent production of chean water and H 2 over the well synthesized Bi/TiO 2. Bi is incorporated to extend the light absorbance capability of TiO 2 to visible light region. Experimental data shows that 3% Bi/TiO 2 exhibits the highest H 2 generation and Total Organic Carbon (TOC) removal. The reduction of TOC of 8% means the conversion of glycerol into H 2 has been achieved, which is in favor of the production of clean water from highly polluted glycerol wastewater. An optimization study is undertaken by varying the calcination temperature to investigate properties-activity relationship of the new photocatalyst, which exhibited higher photocatlytic efficiency under both UV–visible and visible light compared with that of bare TiO 2. The mechanism illustration is derived from the novel materials synthesis and property optimization to explain the rationale behind this interesting phenomenon. It is worth to note that Bi/TiO 2 nanofibers represent a promising photocatalyst for environmental remediation and sustainability where it can be potentially used in glycerol by-product or waste from the industry under the renewable solar irradiation to generate H 2 and clean water simultaneously. [Display omitted] • Bi-incorporated TiO 2 nanofibers exhibited to be able to concurrently generate H 2 and clean water under solar irradiation. • Enhanced physico-chemical properties of Bi/TiO 2 nanofibers. • Enlarged specific surface area & unique mesoporosity. • Enhanced light absorption capability for better photocatalytic reaction, and. • Well-dispersed heterojunctions for an efficient electrons-holes separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two novel POSS bearing norbornene groups (i.e., T 7 N 3 and T 8 N 4) are synthesized. • The addition of T 7 N 3 and T 8 N 4 significantly reduces the k value of PDCPD. • The low- k materials can be rapidly prepared through with low energy consumption approach. Low dielectric constant (low -k, k < 2.5) thermoset polymers play a crucial role in high-frequency communication technology and the microelectronic industry. However, existing low- k materials often suffer from time- and energy-consuming preparation procedures and have k values greater than 2.5. Herein, we present the frontal ring opening metathesis polymerization (FROMP) of dicyclopentadiene and phenyl-functionalized POSS bearing three and four norbornene groups (i.e., T 7 N 3 and T 8 N 4), enabling the rapid formation of high-performance low- k nanocomposites through a low energy consumption approach. The results reveal that T 7 N 3 and T 8 N 4 exhibit excellent compatibility with poly(dicyclopentadiene) (PDCPD) without adversely affecting the materials' FROMP behaviors. Consequently, by increasing IC-POSS content, both the dielectric and comprehensive properties of PDCPD can be significantly enhanced while the influence of IC-POSS type remains limited. In particular, both PT 7 -40 (40 wt% of T 7 N 3 , k = 2.1) and PT 8 -40 (40 wt% of T 8 N 4 , k = 2.12) demonstrate the lowest k values; moreover, PT 8 -40 exhibits the highest dimensional stability (with a coefficient of thermal expansion of 79.3 ppm oC−1), glass transition temperature (188 °C), elastic modulus (2.32 GPa), yield strength (70.4 MPa), and hydrophobicity among all samples. By programming the front velocity, these materials can be processed into complex structures through a combination of FROMP and three-dimensional printing techniques. This work offers a facile and energy-efficient approach for preparing low- k materials with on-demand structures and properties. [ABSTRACT FROM AUTHOR]

Constructing stereocomplex (SC) crystallites at the interface of poly(L‐lactide) (PLLA)/elastomer blends represent a promising strategy to develop heat‐resistant and super‐tough PLLA materials because such SC crystallites can behave as not only nucleator to accelerate crystallization of PLLA matrix but also interfacial binder to strengthen interface. The properties of blends could be largely dominated by the SC interfacial layer, however, it is still unclear how the interfacial structure affects nucleating efficiency and interfacial strength. Herein, taking PLLA/poly(ethylene‐co‐methyl acrylate‐graft‐poly(D‐lactide)) (EMA‐g‐PDLA) blends as an example, EMA‐g‐PDLA bearing different chain lengths and grafting densities is prepared to tailor the size and packing density of interface‐localized SC crystallites. The results indicate that the interfacial structure and properties of the blends have been successfully manipulated. Compared with low‐graft‐density long PDLA chains, high‐graft‐density short ones can readily collaborate with PLLA chains to form numerous SC crystallites with smaller size and higher packing density at the interface and thus dramatically enhance the impact toughness and matrix crystallization rate. Moreover, the toughness is dominated by the content of SC crystallites, but the matrix crystallization is determined by their size and packing density. The work provides a new understanding of SC structure controlling the properties of PLLA/elastomer blends. [ABSTRACT FROM AUTHOR]

The nucleation efficiency (NE) of stereocomplex crystallites (SCs) formed in asymmetric poly(L‐lactide)/poly(D‐lactide) (PLLA/PDLA) blends is generally unsatisfactory because the competition between stereocomplexation and chain mixing involved in the melt‐mixing process can cause low formation efficiency and even severe aggregation of SCs. Herein, it is attempted to achieve high‐efficient formation of finely dispersed SCs particles by designing a unique melt‐mixing procedure, where the mixing of PLLA with 0.75 wt% PDLA is first performed at elevated temperatures (far above the melting temperature of SCs) to allow the homogeneous mixing of PLLA/PDLA chains and then at a low temperature (slightly above that of homocrystallites) to permit the full stereocomplexation of the premixed chains. It is found that the SCs formed in the blends exhibit unexpectedly low NEs (e.g., 54.5%), much inferior to that (73.6%) in the counterpart without undergoing premixing. This is because the introduction of premixing leads to a remarkable deterioration in the amount of SCs particles formed, despite decreased particle size, highlighting that the direct mixing at low temperatures of 170–180 °C (about 20–30 °C lower than that used in common melt‐processing of PLA) is more effective for the construction of SCs with superior NE. The mechanisms for these striking findings are discussed. [ABSTRACT FROM AUTHOR]

Low dielectric constant (k) polymers with excellent comprehensive properties are useful materials in the microelectronics industry as matrix resins or encapsulation layers. With the inherent low polarization, high reactivity, good processability, and low cost, poly(dicyclopentadiene) (PDCPD) has received considerable attention as low‐k materials. However, its practical application is limited by the relatively high thermal expansion and k value. Herein, three norbornene‐functionalized polyhedral oligomeric silsesquioxanes (POSSs) with T8, T10, and T12 polyhedral cores are synthesized and employed for enhancing the dielectric and comprehensive properties of PDCPD via reactive blending. The results show that these POSSs have good compatibility with PDCPD matrix and nano‐dispersed POSSs particles could be obtained. As a result, the materials' properties can be largely enhanced by varying the POSS content and POSS size. Especially, PT12N12‐40 (40 wt% of T12N12) shows the lowest k value (2.1) and coefficient of thermal expansion (63.4 ppm°C−1), highest glass transition temperature (202.5 °C), yield strength (78.0 MPa), and elastic modulus (2.36 GPa), along with excellent hydrophobicity. This study highlights a useful strategy to fabricate high‐performance low‐k polymer nanocomposites by using larger POSS and reactive blending, which provides useful materials for the future microelectronic industry and high frequency communication. [ABSTRACT FROM AUTHOR]

Background. Th17 cell differentiation is involved in the development and progression of many diseases, such as rheumatoid arthritis and systemic lupus erythematosus. Present study mainly focused on the role of LINC-XIST in Th17 cell differentiation. Methods. The naïve CD4+ T cells were isolated from human whole blood. Cells were cultured under Th17 cell-polarizing condition for 6 days. The expression of LINC-XIST and miR-153-3p was measured by qPCR. The relationship between LINC-XIST, miR-153-3p, and ETS1 was predicted by TargetScan website and authenticated by luciferase reporter assay. ELISA assays were conducted to evaluate the IL-17 concentration. Western blot was utilized to measure the protein expression of ETS1. Th17 cell frequency was examined by flow cytometry. Results. The expression of XIST markedly decreased and miR-153-3p expression markedly increased with Th17 cell differentiation. The mRNA expression of IL-17, IL-17 concentration, and Th17 cell frequency were observably decreased in overexpressed LINC-XIST group. Luciferase reporter assay authenticated that miR-153-5p was directly regulated by LINC-XIST. miR-153-3p inhibitor observably decreased IL-17 concentration, mRNA expression of IL-17, and Th17 cell frequency while si-XIST reversed this impact. ETS1 was confirmed to be regulated by miR-153-5p via luciferase reporter assay. In addition, ETS1 markedly decreased IL-17 mRNA expression, IL-17 concentration, and Th17 cell frequency while miR-153-5p mimic reversed this impact. Conclusion. LNCRNA XIST inhibited miR-377-3p to hinder Th17 cell differentiation through upregulating ETS1. [ABSTRACT FROM AUTHOR]

• A novel airfoil flow field is proposed for fuel cells. • Airfoil flow field can enhance mass transfer while maintain low pressure drop. • Fuel cell with airfoil flow field is evaluated via experimental test and simulation. • Airfoil flow field increases the fuel cell's maximum power density effectively. • Airfoil flow field promotes the uniform distributions in fuel cells. Optimal configuration of bipolar plate (BP) embedding flow field is of great significance in improving the power density and durability of proton exchange membrane fuel cells (PEMFCs). Inspired by the airfoil in aircraft dividing the airflow into two streams causing pressure difference, a novel airfoil flow field (AFF) is designed to enhance the mass transfer capacity in channel and across the rib between two adjacent channels, which hardly increases the pressure drop in channel, unlike many baffle designs. The performance improvement achieved by implementing AFF in PEMFC is compared with common parallel flow field (PFF) and the wave flow field (WFF) by experimental test with respect to polarization curve and electrochemical loss and numerical simulation via a three-dimensional (3D) PEMFC model. The experimental results indicate that the novel AFF exhibits best fuel cell performance at various operation conditions (e.g. relative humidity, air stoichiometric ratio) mainly benefitted from the enhanced oxygen transfer, which contributes to the improvement of maximum power density by 8.85 % and 14.37 % compared to PFF and WFF, respectively. The modeling results indicate that the pressure drop increase in AFF is negligible compared with PFF, and is even slightly lower than WFF, indicating high practicability. Moreover, the utilization of AFF also helps the uniformity of oxygen concentration, current density and temperature in PEMFC. [ABSTRACT FROM AUTHOR]

Background. Th17 cell differentiation is involved in the development and progression of many diseases, such as rheumatoid arthritis and systemic lupus erythematosus. Present study mainly focused on the role of LINC-XIST in Th17 cell differentiation. Methods. The naïve CD4+ T cells were isolated from human whole blood. Cells were cultured under Th17 cell-polarizing condition for 6 days. The expression of LINC-XIST and miR-153-3p was measured by qPCR. The relationship between LINC-XIST, miR-153-3p, and ETS1 was predicted by TargetScan website and authenticated by luciferase reporter assay. ELISA assays were conducted to evaluate the IL-17 concentration. Western blot was utilized to measure the protein expression of ETS1. Th17 cell frequency was examined by flow cytometry. Results. The expression of XIST markedly decreased and miR-153-3p expression markedly increased with Th17 cell differentiation. The mRNA expression of IL-17, IL-17 concentration, and Th17 cell frequency were observably decreased in overexpressed LINC-XIST group. Luciferase reporter assay authenticated that miR-153-5p was directly regulated by LINC-XIST. miR-153-3p inhibitor observably decreased IL-17 concentration, mRNA expression of IL-17, and Th17 cell frequency while si-XIST reversed this impact. ETS1 was confirmed to be regulated by miR-153-5p via luciferase reporter assay. In addition, ETS1 markedly decreased IL-17 mRNA expression, IL-17 concentration, and Th17 cell frequency while miR-153-5p mimic reversed this impact. Conclusion. LNCRNA XIST inhibited miR-377-3p to hinder Th17 cell differentiation through upregulating ETS1. [ABSTRACT FROM AUTHOR]

Abstract: Here we present a simple two-phase assembling method to produce high-quality graphene oxide–TiO2 nanorod composites (GO–TiO2 NRCs) on gram scale. TiO2 nanorods dispersed in toluene are synthesized from a facile two-phase hydrothermal method. The effective attachment of TiO2 nanorods on the whole GO sheets at the water–toluene interface is confirmed by Transmission Electron Microscope (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The as-synthesized TiO2 nanorods show a slightly higher efficiency in the photocatalytic degradation of C. I. Acid Orange 7 (AO 7) irradiated under UV light (λ =254nm) and higher antibacterial activity under simulated sunlight than that of TiO2 nanoparticles with the same diameter. After combined with graphene oxide (GO), the GO–TiO2 NRCs show much higher photocatalytic activities than that of TiO2 nanorods alone and the GO–TiO2 nanoparticle composites (GO–TiO2 NPCs). The ratio of TiO2 and GO has no evident effect on the photocatalytic activity of GO–TiO2 NRCs when all the TiO2 nanorods are anchored on the GO sheets. The higher photocatalytic activity of GO–TiO2 NRCs is ascribed to the anti-charge recombination and the more (101) facets. Considering the superior photocatalytic activity of GO–TiO2 NRCs and the fact that they can been easily mass-produced, we expect this material may find important applications in environmental engineering and other fields. [Copyright &y& Elsevier]

Toughening modification of poly(l‐lactide) (PLLA) with rubber particles is often realized at the cost of transparency, mechanical strength, and modulus because high rubber loadings are generally required for toughening. In this work, a promising strategy to simultaneously improve the transparency and stiffness–toughness performance of poly(butyl acrylate)‐poly(methyl methacrylate) (BAMMA) core‐shell rubber nanoparticles toughened PLLA blends by utilizing the stereocomplex (SC) crystallization between PLLA and poly(d‐lactide) (PDLA) is devised. The results reveal that the construction of SC crystallites in PLLA matrix via melt‐mixing PLLA/BAMMA blends with PDLA can prevent BAMMA nanoparticles from aggregation and promote them to form network‐like structure at lower contents. As a result, not only higher toughening efficiency with less rubber contents but also superior transparency is achieved in the PLLA/PDLA/BAMMA blends as compared with the PLLA/BAMMA ones where large aggregated BAMMA clusters are formed. Moreover, the outstanding reinforcement of SC crystallites network for PLLA can impart an enhanced tensile strength and modulus to PLLA/PDLA/BAMMA blends, thus improving the stiffness–toughness performance of PLLA/PDLA/BAMMA blends to a higher degree. This work demonstrates that SC crystallization is a promising solution to solve the contradiction between transparency and mechanical properties and then obtain superior comprehensive performances in rubber toughened PLLA blends. [ABSTRACT FROM AUTHOR]

Ultrathin and/or ultrasmooth selective layer is one of the paramount goals in membrane realm for maximizing separation efficiency and/or minimizing fouling tendency. Towards this goal, the architecture of hydrogel selective layer is finely tuned for the first time for improving engineered osmosis (EO) membrane performance. Through delicately controlling synthesis parameters, ultrathin selective layer as thin as 30 nm, and ultrasmooth selective layer with sub-1 nm roughness (the smoothest EO membrane in literature) are successfully synthesized respectively. Analysis of reverse osmosis (RO) experimental results reveals hydrogel layer resistance to water permeation is linearly reduced by 1.40 × 1013 m−1 as the layer is tailored thinner per 10 nm, which leads to the remarkable enhancement of water permeability by ~10 times from 0.49 L m−2 h−1 bar−1 of 500 nm thickness to 4.75 L m−2 h−1 bar−1 of 30 nm thickness. Pressure-retarded osmosis (PRO) and forward osmosis (FO) tests indicate 45-nm-thick hydrogel layer achieves the maximum separation efficiency in terms of specific water flux (J W /J S). Moreover, the mechanism for tuning hydrogel layer architecture is discussed on the basis of microscopic characterizations. This study sheds new light on ultrathin and ultrasmooth selective layer for promoting EO membrane to smartly tackle different kinds of wastewater. Ultrathin and ultrasmooth hydrogel membranes are synthesized through fine-tuning selective layer architecture for smartly tackling different wastewaters via engineered osmosis with high separation performance. Image 1 • Hydrogel membrane architecture is fine-tuned for engineered osmosis. • Ultrathin hydrogel selective layer as thin as 30 nm is synthesized. • Ultrasmooth hydrogel selective layer with sub-1 nm roughness is achieved. • The effect of hydrogel layer architecture on separation performance is revealed. • Hydrogel membrane holds the promise to smartly tackle different wastewaters. [ABSTRACT FROM AUTHOR]

Abstract: Stereocomplex (SC) crystallization between poly( l‐lactide) (PLLA) and poly( d‐lactide) (PDLA) exhibits tremendous potential to improve the properties of polylactide (PLA), but the practical processing of SC‐type PLA (SC‐PLA) is significantly hindered by the insufficient melt stability and serious degradation after complete melting of SC crystallites over 240 °C. In a previous work, powder metallurgy inspired low‐temperature (180–210 °C) compression sintering is proposed to fabricate SC‐PLA products from its nascent powder. However, its industrial application is still challenging mainly due to the low production efficiency (half an hour is required) as well as the weak ability to fabricate products with complex shapes. In this work, an effort to rapidly fabricate complex‐shaped SC‐PLA products using low‐temperature injection molding technology is reported, where SC‐PLA nascent powder is partially melted. To ensure appropriate powder flowability, small amounts of glyceryl monostearate are incorporated as a lubricant. The results show that, both the self‐nucleation and flow‐induced nucleation effects facilitate the SC crystallization across the interfaces between adjacent unmelted powder particles, which considerably shortens the sintering cycle to about 2 min. In this way, complex‐shaped SC‐PLA products (such as gears) with superb performance are successfully fabricated by injection molding for the first time. [ABSTRACT FROM AUTHOR]

The hydrophilicity of PVDF membrane is playing an enormously important role in its widespread water treatment fields considering the excellent intrinsic properties of PVDF raw materials. Rather than the conventional surface modification or hybridization, herein, we report a novel approach to prepare super-hydrophilic PVDF ultrafiltration (UF) membrane by creating a prefabricated super-hydrophilic surface of inorganic TiO 2 nanoparticles (NPs). The resultant membrane [prepared by prefabrication surface adhesion of TiO 2 NPs on PVDF-PEG-TiO 2 hybrid membrane (SaT-PPT)] has a uniform distribution of TiO 2 NPs not only on the membrane surface but also within membrane matrix, this will maximize the super-hydrophilic feature throughout the membrane: from inner porous structures to outer surfaces, and will avoid “dead-corner” to block fast water pass through. The performances of SaT-PPT membrane as compared with the control membranes (PVDF-PEG, and PVDF-PEG with TiO 2 anchored only at surface) were investigated in terms of humic acid (HA) rejection, flux and flux decline in lab-made cross flow UF experiments with and without UV irradiation. It indicated that SaT-PPT membrane exhibited the highest hydrophilicity and flux, lowest flux decline and total resistance, but still with the highest HA rejection rate. In addition, SaT-PPT membrane showed the highest flux recovery after simple physical cleaning to extend the longer life span of membrane. It is reasonable to believe that our developed SaT-PPT membranes will provide insightful engineering practices to benefit the broad water treatment applications. [ABSTRACT FROM AUTHOR]

The preparation of elastomer/plastic blends with co-continuous structure is beneficial to achieve good shape recovery and fixing performances. In this work, carbon black (CB) nanoparticles with self-networking capability were introduced to tailor the phase morphology and shape memory properties of polylactide (PLA)/thermoplastic poly(ether) urethane (TPU) blend (70/30 by weight). A morphological change from sea-island structure to co-continuous structure was observed with increasing CB content. The strong affinities between CB nanoparticles and TPU as well as the self-networking capability of CB nanoparticles led to the formation of this co-continuous structure. With such novel structure, the PLA70/TPU30/CB ternary composites owned an outstanding shape memory property because the continuous TPU phase provided stronger recovery driving force. Moreover, the selective localization of CB nanoparticles in the continuous TPU phase imparted the composites with enhanced mechanical properties and excellent electrical conductivities with low filler content. The composites then showed a good electroactive shape memory behavior, which could recover to their original shape within 80 s at 30 V. Our work provides a universal strategy via CB self-networking to prepare double percolated conductive polymer composites with optimal shape memory properties and excellent electrical conductivities, which may promote specific applications in intelligent devices. [ABSTRACT FROM AUTHOR]

There are principally two mechanisms to improve the impact resistance of polymer-based composites, intrinsic toughening and extrinsic toughening. But the interplay between them is far from being well understood. Here, glass fiber was incorporated into polypropylene to promote extrinsic toughening mechanism, while addition of elastomer and annealing were adopted for intrinsic toughening. In this way, the interaction among glass fiber, elastomer and annealing could be discussed based on various characterizations, and their combined effect on mechanical properties of the composites could be determined. The results show that the intrinsic toughening mechanism of elastomer will be suppressed by glass fiber irrespective of the support of annealing, though annealing could work synergistically with glass fiber to toughen polypropylene. The possible structure-property relations are discussed. This work will provide deeper insight into the toughening behavior of polymer composites and practical guidance for the design of composites with excellent stiffness-toughness balance. [ABSTRACT FROM AUTHOR]

Bio-degradable polylactide (PLA) based composites has attracted much attention both in academic research and industrial applications in recent decades due to the increasing environmental concerns. In this work, we tried to obtain PLA based composites with good stiffness-toughness balanced properties by adjusting carbon fiber (CF) network in polylactide (PLA) matrix via adding a small amount of soft poly(ether)urethane (PU). It was interesting to find that PU could serve as “solder” to weld CF into a more perfect network due to the fact that PU has stronger interaction with CF as compared with PLA and improve the interface interaction between CF and PLA meanwhile. The self-weld CF network structure was confirmed by SEM characterizations, rheology and conductivity tests. More importantly, the formation of self-weld network structure constructed by both stiff CF and ductile PU elastomer can simultaneously improve tensile strength, impact toughness and even electrical conductivity of PLA. This inspiring result demonstrates that the addition of soft elastomer which has a strong interaction with fiber into fiber-reinforced polymers could be a universal platform to improve the performance of polymer composites via tuning fibers network and the interfacial interaction between fibers and polymer matrix. [ABSTRACT FROM AUTHOR]

[Display omitted] • Larger POSS was introduced into PDCPD to develop low- k materials. • Uniform dispersion of POSS nanoparticles was achieved. • Both POSS size and POSS content can strongly affect the materials' properties. • T 12 V 12 based materials showed the lowest k value and best other properties. Low dielectric constant (low- k) polymer nanocomposites with good comprehensive properties are essential for microelectronics and wireless communication industry. Although extensive studies show that incorporation of polyhedral oligomeric silsesquioxane (POSS) is an effective strategy to realize this purpose, nearly all of them are based on T 8 POSS and the influence of larger POSSs (i.e., T 10 and T 12 POSS) on polymer's properties remains unclear. Herein three vinyl POSSs (T 8 V 8 , T 10 V 10 , and T 12 V 12) with increased sizes were introduced into poly(dicyclopentadiene) (PDCPD) for preparation of high-performance low- k nanocomposites. Because these three POSSs are soluble in dicyclopentadiene monomer, a series of nanocomposites with molecular scale POSS dispersion were achieved after thermo-crosslinking. The results show that the k value of PDCPD can be decreased not only by increasing the content of these three POSSs but also by altering the POSS size. Consequently, the k value of PDCPD at 1 kHz was found to be reduced from 2.54 to 2.10 by adding high content of larger POSS (i.e., 7 wt% of T 12 V 12) without damaging its inherent low dielectric loss. This result highlights the rule of POSS size and POSS content on the dielectric properties and could be used to predicate ultralow- k polymer nanocomposites by extrapolating to larger POSS and higher POSS content. Meanwhile, the comprehensive properties of PDCPD such as glass transition temperature, dimensional stability, mechanical properties, and hydrophobicity, are able to be enhanced by altering the POSS size and increasing the POSS content, making these resulting nanocomposites become useful materials for future microelectronic industry. [ABSTRACT FROM AUTHOR]

As a novel thermoplastic elastomer, olefin block copolymers (OBCs) show a tremendous application potential in many areas. However, the practical use of OBCs is mainly restricted to the low load-bearing environments because of its poor low-strain mechanical strength and stiffness. In this work, short Kevlar fiber was introduced into OBC matrix to improve its mechanical properties. The results show that introduction of pristine Kevlar fiber only gives rise to a slight increase in tensile strength of OBC owing to the poor interfacial strength, regardless of the presence of compatibilizer maleic anhydride-grafted polypropylene (MA-g-PP). However, a largely enhanced tensile strength can be easily obtained when hydrolyzed or polydopamine-coated Kevlar fiber was incorporated into the OBC matrix using the MA-g-PP as the reactive compatibilizer. More importantly, the tensile strength can be further enhanced with the orientation of Kevlar fiber in the composites. As compared with compression molded composites with randomly orientated fibers, injection molded composites with highly oriented fibers exhibit a significantly higher tensile strength at the same composition. Moreover, it is interesting to observe that Kevlar fiber can be easily exfoliated into several microfibers during melt-mixing with OBC, but the exfoliation has no evident effect on the reinforcement effect possibly because of the poor interfacial strength between the newly-formed microfibers and the OBC matrix. Our work demonstrates that mechanical performance of short fiber reinforced elastomer composites could be significantly improved by enhancing interfacial strength and fiber orientation using a facile surface modification strategy and conventional melt-processing technology. [ABSTRACT FROM AUTHOR]

Abstract: β-Modification and annealing were adopted to improve the impact strength of long glass fiber reinforced (LFPP) composites. It was found that either β-modification or annealing is an efficient way to toughen LFPP composites, and largely enhanced impact toughness can be achieved via simultaneously using β-modification and annealing, particularly for the toughness at low temperatures (−40°C to −20°C). Meanwhile, the tensile strength and Young’s modulus of the composites could be maintained. Various characterizations were used to understand the microstructure changes and toughening mechanism after β-modification and annealing. The results show that the higher extent of the matrix plastic deformation could be the main reason for the enhanced toughness as induced by β-modification and annealing. The possible structural origins for the higher extent of matrix plastic deformation are also discussed. [Copyright &y& Elsevier]

Abstract: Sodium hydrosulfite is used to reduce graphite oxide in current study. The preparation of poly (vinyl alcohol) (PVA)/graphene nanocomposites is realized using two simple steps: the synthesis of PVA/graphite oxide (GO) nanocomposites film and immersion of such a film in the reducing agent aqueous solution. This method prohibits the agglomeration of GO during direct reduction in PVA/GO aqueous solution, and opens a new way to scale up the production of graphene nanocomposites using a simple reducing agent. A 40% increase in tensile strength and 70% improvement in elongation at break have been obtained with only the addition of 0.7wt.% of reduced graphite oxide. Furthermore, a good level of conductivity and a variation in the surface property of the prepared films have been observed for the composites containing graphene. [Copyright &y& Elsevier]

Abstract: One-dimensional mesoporous TiO2 nanotube (TNT) with large specific surface area was successfully fabricated, and employed in removal of Acid Orange 7 (AO7) via adsorption and heterogeneous photocatalysis. As compared to its precursor, P25 (Degussa), TNT exhibited superior adsorption ability and photocatalytic activity. It was found that the amount of adsorbed dye over TNT surface was critical to the photodegradation efficiency of AO7, and adsorption was further controlled by solution pH and co-existing ions. With an increase in pH, adsorption of AO7 decreased rapidly, and adsorption behavior transformed from monolayer adsorption to asymmetric physisorption. Under low pH conditions, multivalent anions in high concentrations severely limited AO7 adsorption on TNT; whereas the increase of pH led to a less severe inhibition of the adsorption. On the other hand, multivalent cations seem to facilitate adsorption, regardless of pH conditions. Adsorption mechanism and photodegradation kinetics of AO7 on TNT were also discussed in the paper in view of paving the way for efficient dye wastewater treatment with the application of TNT photocatalyst. [Copyright &y& Elsevier]

Abstract: The impact fracture behaviors of polyamide 6 (PA6) composites with tetra-needle-shaped zinc oxide whisker (T-ZnOw) are studied in this work. Two different silane coupling agents, KH-550 with amino groups and KH-560 with epoxy groups, are used to treat T-ZnOw. The results show that the coupling agent types, content as well as the T-ZnOw content have much influence on the impact fracture behaviors of T-ZnOw/PA6 composites. Compared with the composites filled with untreated T-ZnOw, in which the impact strength decreases linearly with the increasing content of filler, chemical treated T-ZnOw improves the impact strength of the composites apparently due to the improved interfacial interaction between T-ZnOw and matrix. Further results show that the main toughening mechanisms of treated T-ZnOw in PA6 composites include the pullout of T-ZnOw from matrix, the anchoring role of other three needles when one of the four needles of T-ZnOw is pulled out from matrix, and the local yielding or deformation of matrix around the T-ZnOw. [Copyright &y& Elsevier]

Abstract: In this work, multi-walled carbon nanotubes were successfully chemically modified by maleic anhydride (f-MWCNTs), and the f-MWCNTs were melt compounded with poly(ethylene terephthalate) (PET) by using a twin-screw extruder to prepare nanocomposites. The effects of f-MWCNTs on the crystallization behavior of PET nanocomposites were studied via DSC and POM. The results show the apparent nucleation effect of f-MWCNTs in PET crystallization. The cold-crystallization peak temperature decreases with the increase of f-MWCNTs during the heating process. On the other hand, the addition of f-MWCNTs can greatly enhance the melt-crystallization peak temperature of PET when it is cooled from the melt. The nonisothermal crystallization kinetics of PET with f-MWCNTs was analyzed by different methods and the results also prove that the f-MWCNTs clearly accelerate the crystallization process of PET. [Copyright &y& Elsevier]

To address the worldwide oil and water separation issue, a novel approach was inspired by natural phenomena to synthesize superhydrophilic and underwater superoleophobic organic/inorganic nanofibrous membranes via a scale up fabrication approach. The synthesized membranes possess a delicate organic core of PVDF-HFP and an inorganic shell of a CuO nanosheet structure, which endows super-flexible properties owing to the merits of PVDF-HFP backbones, and superhydrophilic functions contributed by the extremely rough surface of a CuO nanosheet anchored on flexible PVDF-HFP. Such an organic core and inorganic shell architecture not only functionalizes membrane performance in terms of antifouling, high flux, and low energy consumption, but also extends the lifespan by enhancing its mechanical strength and alkaline resistance to broaden its applicability. The resultant membrane exhibits good oil/water separation efficiency higher than 99.7%, as well as excellent anti-fouling properties for various oil/water mixtures. Considering the intrinsic structural innovation and its integrated advantages, this core–shell nanofibrous membrane is believed to be promising for oil/water separation, and this facile approach is also easy for scaled up manufacturing of functional organic/inorganic nanofibrous membranes with insightful benefits for industrial wastewater treatment, sensors, energy production, and many other related areas. [ABSTRACT FROM AUTHOR]

Managing the wastewater discharged from oil and shale gas fields is a big challenge, because this kind of wastewater is normally polluted by high contents of both oils and salts. Conventional pressure-driven membranes experience little success for treating this wastewater because of either severe membrane fouling or incapability of desalination. In this study, we designed a new nanocomposite forward osmosis (FO) membrane for accomplishing simultaneous oil/water separation and desalination. This nanocomposite FO membrane is composed of an oil-repelling and salt-rejecting hydrogel selective layer on top of a graphene oxide (GO) nanosheets infused polymeric support layer. The hydrogel selective layer demonstrates strong underwater oleophobicity that leads to superior anti-fouling capability under various oil/water emulsions, and the infused GO in support layer can significantly mitigate internal concentration polarization (ICP) through reducing FO membrane structural parameter by as much as 20%. Compared with commercial FO membrane, this new FO membrane demonstrates more than three times higher water flux, higher removals for oil and salts (>99.9% for oil and >99.7% for multivalent ions) and significantly lower fouling tendency when investigated with simulated shale gas wastewater. These combined merits will endorse this new FO membrane with wide applications in treating highly saline and oily wastewaters. [ABSTRACT FROM AUTHOR]