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Shape memory polymers (SMPs) are the simplest and most attractive alternatives for soft substrates of typical bilayer wrinkle systems because of shape fixity and recovery capabilities. Herein, we have successfully programmed large compressive strains in chemical cross-linking shape memory polystyrene (PS) microparticles via nanoimprint lithography, which acted as the substrate of a wrinkle system using a gold nanoparticle (Au NP) film as the top layer. When triggered by two different stimuli (direct heating and toluene vapors), the thin Au NP film could transform into various wrinkle structures atop the recovered PS particles. In addition, we also investigated the evolution mechanisms of wrinkling by heating and toluene vapors and tuned the wrinkled surfaces through altering the Au NP thickness and stimulation methods (direct heating and toluene vapors), which utilized the structural adjustability of Au NPs to program the amplitude, wavelength, and morphology of the wrinkles. The concept presented here provides a cost-effective approach to realize the surface wrinkling and can be extended to other available SMPs.

High-performance shape memory thermosetting polymers and their composites for four-dimensional (4D) printing are essential in practical applications. To date, most printable thermosets suffer from complicated processes, poor thermodynamic performances, and low printing speed. Here, photosensitive composite inks for fast photocuring printing are developed. The inks consist of epoxy acrylate (EPAc), polyethylene glycol dimethacrylate (PEGDMA), and carbon fillers, which form a firm network structure when exposed to UV light. EPAc is synthesized via addition esterification of epoxy resin and acrylic acid under mild conditions. It is worth noting that raw materials for the reaction are diverse, including not only various epoxy resins but also molecules with epoxy groups. The 4D printing speed of up to 180 mm/h is mainly attributed to the exothermic reaction initiated by free radicals, which accelerates the polymerization of EPAc and PEGDMA. Most importantly, by increasing the exposure time of each layer from 1 s to 3 s during the printing process, the epoxy composite-infilled carbon nanotubes and carbon fibers are printed to ensure the integrity of the microlayer structure. Furthermore, we design a claw-like catcher device based on the above printable composite inks to demonstrate its potential applications in aerospace, such as grasping end-of-service spacecraft or explosive debris. Undoubtedly, 4D printing technology opens up a new portal for the manufacturing of thermoset epoxy composites and complex structures, which make the shape memory thermosetting epoxy resins and their composites possess excellent properties and good engineering application prospects.

PM2.5 and its main chemical components have been investigated during six air pollution periods across four seasons from Jun. 16, 2016 to Jun. 15, 2017 at a suburban site in Beijing, China. Daily PM2.5 mass concentrations were measured with associated ions, OC, EC, 16 PAHs and seven heavy metals. Mass closure analyses were conducted using measured and reconstructed chemical components. Chemical ratios were used to identify possible pollution sources, while principal component analysis (PCA) coupled with multiple linear regression (MLR) method was used to estimate the source contribution to PM2.5 mass. The annual mean PM2.5 concentration (96.7 μg m−3) is about 2.8 times the national level-2 standard limit, with apparent seasonal variation of daily exceedances as winter > spring > autumn > summer. Generally, higher levels are observed in winter and autumn than in spring and summer for NO3−, SO42−, NH4+, Cl−, K+, OC, EC, PAHs and metals Zn, As, Cu, Pb, along with higher concentrations of NOx, CO and SO2. Secondary ions and carbon fractions are most abundant over all seasons, except levels of dust related species Ca2+, Mg2+, Ca, Fe and Mn are also high in spring. The reconstructed results show that PM2.5 consists of mostly organic compounds (26–38%) and ammonium salts (NH4NO3 + (NH4)2SO4) (43–53%) in winter and autumn, while summer is dominated mainly by ammonium salts (81%). In spring, very high PM2.5 episodes are occasionally composed of large amount of soil/road dust and gypsum particles (23–55%) due to floating dust events with drier weather conditions and human activities. Fuel combustions and secondary sources are responsible for ~70% of PM2.5 mass while mobile source is mostly a regional origin.

This study aims to investigate the dynamic changes over time in the immobilization efficiency of hydroxyapatite, bentonite, and biochar for Cd and Pb co-contaminated soil given the potential remobilization of immobilized heavy metals for long-term stabilized soils. Hydroxyapatite, bentonite, and biochar were applied only once at 2.5% (w/w) of soil during a 5-year pot experiment with pepper-cabbage (Capsicum annuum L.-Brassica pekinensis) rotation. The dynamic changes of soil pH, soil organic carbon (SOC), TCLP (toxicity characteristic leaching procedure)-, DTPA-, and PBET (simulated human gastric solution extraction)-Cd and Pb in soil, fractionation of Cd and Pb in soil, as well as the dynamic variations of bioaccessible Cd and Pb in vegetables were determined. The results indicated the application of hydroxyapatite, bentonite, and biochar significantly increased the proportion of residual fraction of Cd and Pb, and reduced the mobility, bioavailability, and bioaccessibility of Cd and Pb analyzed by TCLP, DTPA, and PBET, respectively. Moreover, the concentrations of TCLP-, DTPA-, and PBET-Cd and Pb gradually increased over time. The proportions of acid-extractable Cd and Pb in amended treatments in 2019 were higher than those in 2016. The increment for acid-extractable Cd fraction was 4.69%, 5.53%, and 4.19% in hydroxyapatite, bentonite, and biochar, respectively. While the increment for acid-extractable Pb fraction was 1.48%, 2.08%, and 1.91%, respectively. The bioaccessible Cd and Pb in pepper and cabbage significantly decreased after remediation while no remarkable changes were observed for Pb from 2017 to 2019. The three amendments were effective ameliorants for Cd and Pb co-contaminated acidic soil, but the immobilization efficiency decreased over time. Moreover, hydroxyapatite showed the highest efficiency on metal stabilization and vegetable safety.

The concentration level of cytokeratin fragment antigen 21-1 (CYFRA21-1) can be used as an important indicator for predicting non–small cell lung cancer (NSCLC). Here, a sandwich-type electrochemical immunosensor for ultrasensitive detection of CYFRA21-1 is developed. The sensor based on a combination of gold nanoparticle (AuNPs) decorated Ti3C2Tx-MXene (Au-Ti3C2Tx) as the substrate enhancer, and toluidine blue (TB) modified AuNPs doped covalent organic framework (COF) polymer as the signal tag (TB-Au-COF). The Au-Ti3C2Tx is used to capture numerous primary antibodies and accelerate the electron transfer rate of the substrate, while the TB-Au-COF can be applied to provide a large number of signal units TB and secondary antibodies. These features of composites endow the proposed immunosensor with high sensitivity and current response to CYFRA21-1. Under optimum conditions, the immunosensor offers a wide current response for CYFRA21-1 from 0.5–1.0 × 104 pg·mL−1 with a detection limit of 0.1 pg·mL−1. Furthermore, the biosensing platform can be applied for CYFRA21-1 detection to analyze real serum samples, providing an effective and useful avenue for the applicability of Au-Ti3C2Tx and TB-Au-COF composite materials in biosensing field.

Although ginsenoside Rg3 is very important in pharmaceutical field, the application of this drug is greatly limited by the release rate due to its poor dissolution. Here we introduced a meso/macroporous SiO2 to assist dispersing Rg3. The as-obtained SiO2/Rg3 (m/M-SiO2/Rg3) with this well-designed support showed superior Rg3 release rate compared to a mesoporous SiO2/Rg3 (m-SiO2/Rg3) at the same release duration and Rg3 loading 20 wt%. The excellent performance of the carrier drug could be attributed to the structural characteristics of hierarchically porous SiO2. On one hand, the macropores (~ 270 nm) accommodate for the active ingredient as effective reservoirs, more importantly the interconnected macropores efficiently shortens the paths of transferring Rg3, which facilitates releasing Rg3 at the nearest mesoporous channels (~ 2.8 nm) penetrated on the wall of adjacent macropores.

Cardamonin (CDM) is a natural chalcone with strong anti-inflammatory properties. Inflammation-induced osteogenic changes in valve interstitial cells (VICs) play crucial roles in the development of calcific aortic valve disease (CAVD), a degenerative disease characterized by degeneration, thickening, fibrosis, and calcification of the heart valve tissues. To investigate the anti-osteogenic differentiation role of CDM in human valve interstitial cells (hVICs), which consequently reverses the calcification of the aortic valve, human VICs were exposed to osteogenic induction medium (OM) with CDM for further cell viability, osteogenic gene and protein expression analyses, and anti-calcification testing. mRNA sequencing was utilized to analyze the differentially expressed genes (DEGs) and related signaling pathways as potential molecular targets involved in CDM's anti-calcification activity. Human aortic valve leaflet ex vivo calcific cultures were used to investigate the CDM inhibition of osteogenic differentiation of hVICs at the tissue level. ApoE-/- mice fed with a high-fat (HF) diet were used to evaluate the effect of CDM on aortic valve calcification. No significant CDM cytotoxicity was seen in the hVICs at 10 μM. The addition of CDM to OM prevented calcified nodule accumulation, and a decrease in the gene/protein expression levels of BMP2, RUNX2, SPP1, TNF-α, and COL1A2 was observed. Venn diagram analysis of the DEGs identified 666 common DEGs and highlighted the NOD-like receptor signaling pathway (ko04621) as an anti-calcification target of CDM. CDM also repressed the activation of p-AKT, p-ERK1/2, and p-IκBα, and prevented the OM-induced nuclear transcription of NF-κB p65. In the in vitro and ex vivo calcific conditional culture experiments, CDM exhibited anti-inflammatory and anti-calcification effects by suppressing the activation of the NLRP3 inflammasome and downregulating IL-1β expression. In vivo, CDM ameliorated aortic valve calcification by interfering with NLRP3 expression. Our study demonstrated that CDM inhibited the phenotypical calcific transformation of hVICs by mediating the inactivation of the NF-κB/NLRP3 inflammasome. Therefore, it is considered to be a promising natural compound for use in preventing the progression of heart valve calcification disease.

There is increasing interest in understanding the role of airborne chemical components in modulating the cell cycle of human bronchial epithelial (HBE) cells that is associated with burden of cardiopulmonary disease. To address this need, our study collected ambient PM10 (particles with aerodynamic diameter less than or equal to 10 μm) and PM2.5 (particles with aerodynamic diameter less than or equal to 2.5 μm) across four sampling sites in Beijing during the year of 2015. Chemical components including organic carbon (OC), elemental carbon (EC), polycyclic aromatic hydrocarbons (PAHs), metals and water soluble ions were determined. Spearman's rank-order correlation was performed to examine the associations between chemical components in ambient particles and cell cycle distributions with p-values adjusted by Bonferroni methodology. Our results demonstrated the significant associations between certain chemical compositions (i.e., PAHs, EC, As and Ni) and percentages of HBE cells in G0/G1 and G1/G2 phases, respectively. Our results highlighted the need to reduce the specific toxins (e.g., PAHs, EC, As and Ni) from ambient particles to protect cardiopulmonary health associated with air pollution. Future study may focus on illustrating the mechanism of certain chemical compositions in altering the cell cycle in HBE cells.

In this paper, a high sensitivity and accuracy biosensor for CEA detection based on atom transfer radical polymerization (ATRP) with β-cyclodextrin (β-CD) and 2-bromoisobutyryl bromide (BIBB) as a macroinitiator is reported for the first time. Carcinoembryonic antigen (CEA), as a tumor-associated antigen, can be of great significance in the diagnosis of illness. Herein, thiolated CEA-aptamer 1 (Apt 1) at the 5′-terminal is first immobilized on amino magnetic beads (MBs) via a cross-linking agent to specifically recognize the antigen of CEA. After the sandwich-type structure formed, β-CD, with a bridging effect, is linked to the carboxylation CEA-aptamer 2* (Apt 2*) and BIBB via esterification reaction and substitution reaction, respectively. Remarkably, the combination of β-CD and the initiators BIBB can provide a large number of active sites for monomers and significantly amplify the fluorescent signal. Under optimum experimental conditions, the proposed biosensor for detecting CEA has a strong linear relationship in the wide detection range of 1.0 × 10−15–1.0 × 10−7 g mL−1 (R2 = 0.9989), and it is capable of detecting as low as 6.76 ag mL−1 CEA. Furthermore, the fluorescence biosensor exhibits splendid analytical performance in practical sample analysis. More importantly, the excellent sensitivity with outstanding anti-interference properties of this proposed biosensor makes it of great potential in the field of bioanalytical applications.

To understand the impact of fireworks on heavy metals in dust, the human health and ecological risks and source identification of six common heavy metals, lead (Pb), chromium (Cr), arsenic (As), copper (Cu), zinc (Zn) and nickel (Ni), were investigated in aged dust (AD) and fireworks dust (FD) collected from seven main administrative districts in Beijing. The health risk was assessed with the hazard quotient (HQ) and hazard index (HI) for non-carcinogenic elements and the carcinogenic risk (RI) for carcinogenic elements. The potential ecological risk was estimated based on the ecological risk index (RI). Principal component analysis (PCA) and Pearson correlation analysis were conducted to identify the main sources of the heavy metals. The results showed that the mean concentrations of these metals in both AD and FD were much higher than the corresponding background values in Beijing soil; the Cu and Zn concentrations were significantly elevated by firework burning, while the other four metal concentrations in AD and FD were similar. The HQ and HI values for Cr, Zn, As and Cu in FD were higher than those in AD, indicating that the health risk of heavy metals in dust increased due to firework burning. The ecological risk of the above heavy metals in five of the seven studied districts increased from low to moderate or considerable risk after firework burning. Based on the PCA results, fireworks are an extra pollution source for heavy metals in dust. This research will help the government to implement effective measures to improve urban environmental quality.

The compatibility of polylactic acid (PLA)/polybutylene succinate (PBS) blends was studied by molecular dynamics and mesoscopic dynamics, which is a controversial issue in experiments. Six simulation models of PLA/PBS with different composition ratios (100/0, 90/10, 80/20, 70/30, 60/40, 0/100) were constructed. The radial distribution function, hydrogen bond, free energy density, order parameter and iso-density surface morphology of the PLA/PBS systems were simulated and analyzed. Due to the formation of hydrogen bonds and van der Waals bonds between different elements of PLA chains and PBS chains, the PLA/PBS blends exhibit good compatibility at all composition ratios.

In this paper, a series of shape-memory poly(arylene ether ketone)s (PAKEs) with various flexible groups (i.e., carbolic bonds, ether, and ketone linkages) and entangled crystalline polymeric structures were synthesized by combining different bisphenol monomer (bisphenol A monomer and methyl hydroquinone monomer) proportions with a 4,4′-difluorobenzophenone monomer. The flexible parts and the entangled parts acted as a reversible phase and permanent phase, respectively. The prepared PAEK films exhibited excellent heat-triggered shape-memory behaviors with tunable glass transition temperatures (Tg) from 116 °C to 140.5 °C including an extremely high fixity ratio (over 98%), high recovery ratio (over 92%), and fast recovery rate (within 7.0 s). As increasing the content of the methyl hydroquinone monomer in the structural unit, the recovery ratio showed a downward trend, whereas the recovery time increased gradually. In addition, the electric-triggered shape-memory effect of the PAEK films was achieved via the introduction of carbon nanotubes (CNTs). Upon applying a voltage of 25 V, the recovery ratios of the composite films containing 10 wt% and 15 wt% CNTs were all over 80% (of 83.0% and 87.6%, respectively), indicating a great electric-triggered shape-memory behavior. The recovery ratio increased and the triggered voltage decreased as increasing the content of CNTs. The heat and electric dual-triggered shape-memory PAEK composites could be important smart materials possessing wide application prospects.

Pacman dinuclear CoII triphenylporphyrin-tri(pentafluorophenyl)porphyrin 1 and dinuclear CoII bis-tri(pentafluorophenyl)porphyrin 2, anchored at the two meso-positions of a benzene linker, are synthesized and examined as electrocatalysts for the oxygen reduction reaction (ORR). Both dinuclear Co bisporphyrins are more efficient and selective than corresponding mononuclear CoII tetra(pentafluorophenyl)porphyrin 3 and CoII tetraphenylporphyrin 4 for the four-electron electrocatalytic reduction of O2 to water. Significantly, although the ORR selectivities of the two dinuclear Co bisporphyrins are similar to each other, 1 outperforms 2, in terms of larger catalytic ORR currents and lower overpotentials. Electrochemical studies showed different redox behaviors of the two Co sites of 1: the CoIII/CoII reduction of the Co-TPP (TPP = triphenylporphyrin) site is well-behind that of the Co-TPFP (TPFP = tri(pentafluorophenyl)porphyrin) site by 440 mV. This difference indicated their different roles in the ORR: CoII-TPFP is likely the O2 binding and reduction site, while CoIII-TPP, which is generated by the oxidation of CoII-TPP on electrodes, may function as a Lewis acid to assist the O2 binding and activation. The positively charged CoIII-TPP will have through-space charge interactions with the negatively charged O2-adduct unit, which will reduce the activation energy barrier for the ORR. This effect of Co-TPP closely resembles that of the CuB site of metalloenzyme cytochrome c oxidase (CcO), which catalyzes the biological reduction of O2. This work represents a rare example of asymmetrical dinuclear metal catalysts, which can catalyze the 4e reduction of O2 with high selectivity and significantly improved activity.

Alkaline phosphatase (ALP) activity is a diagnostic indicator for a variety of clinical diseases. In this study, an electrochemical method for detecting ALP activity through activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) was developed. Specifically, 3-mercaptopropionic (MPA) was firstly fixed on the electrode through sulfur–gold bonding. Subsequently, α-bromophenylacetic acid (BPAA) as initiator was attached to MPA through the recognized carboxylate-Zr4+-phosphate chemistry. Finally, in the existence of ALP, L-Ascorbic acid 2-phosphate sesquimagnesium salt hydrate (AAPS) was hydrolyzed to produce ascorbic acid (AA) which participated in the ARGET ATRP reaction, grafting polymer containing plenty of ferrocene electroactive probes on the surface of electrode. Under optimal experimental conditions, this method had a linear scope of 20–200 mU mL−1, and a limit of detection (LOD) of 1.64 mU mL−1. In addition, the proposed method had good selectivity as well as anti-interference capability, with satisfactory results in inhibition rate and human serum experiments. By merits of good analytical performance, easy operation, and low cost, such a method for ALP activity detection has promising applications in ALP-related disease detection and inhibitor screening.

As an important hydrolytic enzyme, abnormal activity of alkaline phosphatase (ALP) is closely associated with a variety of diseases. It has been identified as an important diagnostic indicator for clinical hepatobiliary and bone diseases. Herein, a novel electrochemical sensor based on signal amplification strategy through ring-opening polymerization (ROP) has been developed to assay of ALP activity. First of all, 3-mercaptopropanoic acid (MPA) was employed as a cross-linking agent to attach O-phosphoethanolamine to the electrode surface via amide bond. Then, ALP catalyzed the hydrolysis of phosphate monoester structures to hydroxyl groups, which could initiate ROP reaction. The polymer grafted on the electrode surface contains a large number of ferrocene electroactive molecules, which effectively increased the signal output of the electrochemical sensor and improved the sensitivity of ALP activity detection. Under optimum conditions, this electrochemical sensor rendered a satisfactory linear dependence over the range from 20 to 120 mU mL-1, with a low detection limit of 0.66 mU mL-1. Furthermore, this strategy presented satisfactory selectivity and interference resistance in human serum sample, and compared with clinical data, the relative error of the results obtained by this method was less than 5%. Thus, this method showed considerable potential for the detection of ALP activity in clinical application.

In this study, we investigated the therapeutic effects and mechanism of atractylodin (ATL) on dextran sulfate sodium (DSS)-induced ulcerative colitis in mice. We found that atractylodin could significantly reverse the effects of DSS-induced ulcerative colitis, such as weight loss, disease activity index score; shorten the colon length, and reverse the pathological changes in the colon of mice. Atractylodin could inhibit the activation of colonic macrophages by inhibiting the MAPK pathway and alleviate intestinal inflammation in the mouse model of ulcerative colitis. Moreover, it could protect the intestinal barrier by inhibiting the decrease of the tight junction proteins, ZO-1, occludin, and MUC2. Additionally, atractylodin could decrease the abundance of harmful bacteria and increase that of beneficial bacteria in the intestinal tract of mice, effectively improving the intestinal microecology. In an LPS-induced macrophage model, atractylodin could inhibit the MAPK pathway and expression of the inflammatory factors of macrophages. Atractylodin could also inhibit the production of lactate, which is the end product of glycolysis; inhibit the activity of GAPDH, which is an important rate-limiting enzyme in glycolysis; inhibit the malonylation of GAPDH, and, thus, inhibit the translation of TNF-α. Therefore, ours is the first study to highlight the potential of atractylodin in the treatment of ulcerative colitis and reveal its possible mechanism.

A new Cd(II) complex, [Cd(H4pbidc)(H2O)] n (1), incorporating 2,2′-(propane-1,3-diyl)bis(1H- imidazole-4,5-dicarboxylic acid) (H6pbidc) was synthesized and characterized by elemental analysis, infrared spectra and X-ray single-crystal diffraction. In complex 1, each Cd(II) ion is hepta-coordinated, showing a significantly distorted pentagonal-bipyramidal coordination environment. Adjacent Cd(II) ions are alternately joined through two carboxylate oxygen atoms and two bridging water molecules resulting in a one-dimensional chain structure. In the solid state, adjacent chains are further linked by hydrogen bonds, forming a three-dimensional supramolecular architecture. Meanwhile, the interactions of complex 1 with bovine serum albumin were analysed by fluorescence measurements under physiological conditions. The results indicated that the fluorescence intensity of bovine serum albumin was decreased considerably upon the addition of complex 1 through a static quenching mechanism with formation of one binding site. The negative values of the thermodynamic parameters including enthalpy change (Δ H), entropy change (Δ S) and Gibbs free energy change (Δ G) showed that hydrogen bonding and van der Waals forces were the main interactions in the binding of complex 1 to bovine serum albumin, and the binding process is spontaneous in thermodynamics.

In this study, spray characteristics of biodiesel blending with di-n-butyl ether (DBE15, DBE30) were investigated by experiment and analysis and compared with diesel. Spray characteristics parameters including spray tip penetration, spray cone angle, maximum spray width and spray tip velocity were used to compare under different injection pressures and ambient pressures. The spray images were analyzed according to light intensity level, while the gas entrainment mass and equivalent ratio were analyzed by empirical model. The results showed that the spray tip penetration of biodiesel added with DBE was reduced and the spray cone angle and maximum spray width were increased. The range of light intensity level of biodiesel was the narrowest, while the light intensity level of biodiesel-DBE blends was similar to that of diesel. Empirical models showed that biodiesel shows poor gas-fuel mixing. DBE30 had a larger gas entrainment mass and a lower equivalence ratio, similar to diesel. It was proved that the biodiesel added with DBE enhanced the gas-fuel mixing.

The detection of hydrogen peroxide (H2O2) is essential due to its extensive application in bio-medical and environment. Herein, we synthesized a novel polyethyleneimine-Au nanoparticle-copper protoporphyrin (PEI-AuNPs-CuPP) nanocomposite toward H2O2 detection. Ultraviolet-visible spectrometry (UV-vis), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FTIR) were used to characterize this nanomaterial. Analytical performance of this proposed sensor was evaluated through differential pulse voltammetry (DPV) and cyclic voltammetry (CV). It was found surprisingly that the PEI-AuNPs-CuPP-based sensor exhibited sensing for H2O2 with a detection limit of 91.74 aM. In addition, this sensor displayed superb selectivity in the presence of dopamine (DA), ascorbic acid (AA), uric acid (UA), and glucose (Glu), which held satisfactory analytical performance for the detection of H2O2 in human serum samples, indicating a promising application in biological sample analysis.

In this assay, a new polyethyleneinmine-gold nanoparticles-protoporphyrin cobalt (II) (PEI-AuNPs-CoPP) nanocomposite was synthesized by a simple method under mild conditions, and it was used to fabricate an electrochemical sensor for the detection of hydrogen peroxide (H2O2). The structures of nanomaterials were characterized by fourier transform infrared (FTIR) spectroscopy and ultraviolet visible spectrometry (UV–vis). Under the optimum condition, the current intensity was linearly related to H2O2 concentration in the range of 50–280 aM (R2 = 0.9932). It's worth mentioning that a lower detection limit of 7.26 aM was obtained at a signal-to-noise rate of 3. In addition, the experiments showed that ascorbic acid (AA), uric acid (UA) and glucose (Glu) had little effect on the determination of H2O2. The sensor had a good analytical performance for the determination of H2O2 in human serum samples. These results suggested that the proposed PEI-AuNPs-CoPP nanocomposites had practical application prospect in biological sample analysis and clinical diagnosis.

Shape-memory polymers (SMPs) and their composite materials are stimuli-responsive materials that have the unique characteristics of lightweight, large deformation, variable stiffness, and biocompatibility. This paper reviews the research status of the mechanical models for SMPs, shape-memory nanocomposites and shape-memory polymer composites (SMPCs); it also introduces some spatially deployable structures, such as hinges, beams, and antennae based on SMPCs. In addition, the deformation types of 4D printing structures and the potential applications of this technology in robots and medical devices are also summarized.

Butane has the potentiality to be a new-era energy source. MILD combustion can be realised by jet flame in vitiated co-flow. Lift-off height is an important parameter of jet flame in vitiat...

In this study, spray characteristics of biodiesel blending with di-n-butyl ether (DBE15, DBE30) were investigated by experiment and analysis. Spray characteristics parameters including spray tip penetration and spray cone angle were used to compare the atomization effect under different injection pressures and ambient pressures. The spray tip penetration was logarithmically used to analyze the breakup time and to correct the empirical formula available from literature. The results show that the spray tip penetration of the blends added a certain proportion of di-n-butyl ether was shortened, and the spray cone angle was increased. In addition, the correction formula for introducing the density term was more suitable for the data of this experiment than the conventional empirical formula for predicting the spray tip penetration.

The objective of this paper is to investigate the flame structure and liftoff behaviors of a dimethyl ether central jet in CH4/air vitiated coflow in a coflow burner. The liftoff behaviors of dimethyl ether jet flames in the air flow were studied firstly. The flame stability of the burner was analyzed by measuring the flow field temperature with thermocouples. By changing the coflow rate and CH4 equivalence ratio, the liftoff behaviors of dimethyl ether jet flames under different vitiated coflow environments were discussed. The jet flame structure was also analyzed qualitatively by high-speed photography.

Elaeis guineensis is a tropical crop with high oil content, and the nutritional value of oil is very high. Amino acids not only affect the growth and development of plants but also act as intermediate metabolites of oils, which determine the final quality of oils. In this study, eleven amino acid permease genes (EgAAPs) in E. guineensis were identified from the amino acid transporter family. Real-time PCR results showed that seven EgAAPs (EgAAP1, EgAAP2, EgAAP3, EgAAP4, EgAAP6 EgAAP9, and EgAAP10) played an important role in vegetative growth because of their higher expression levels in roots and leaves, but EgAAP5, EgAAP7, EgAAP8 and EgAAP11 were also important for their higher expression levels in flowers or fruits. E. guineensis seedlings were treated with 20% PEG-6000 and 4 °C to induce drought stress and cold stress, respectively. The expression of six EgAAPs (EgAAP1, EgAAP2, EgAAP4, EgAAP6, EgAAP8 and EgAAP11) was decreased in both roots and leaves during cold treatment, and only the expression of EgAAP5 was increased in both roots and leaves after 6 h of cold treatment. The expression of six EgAAPs (EgAAP2, EgAAP4, EgAAP7, EgAAP8, EgAAP10 and EgAAP11) was decreased in roots but increased in leaves under PEG treatment, indicating an opposite pattern of expression levels of these EgAAPs in roots and leaves. However, only EgAAP5 had a similar pattern of expression levels between roots and leaves under PEG treatment. The findings provide information on how EgAAPs in E. guineensis are regulated during growth and development, and under various environmental stresses.

Solution self-assembly of a linear ABA triblock copolymer with two terminal crystallizable poly(ferrocenyldimethylsilane) (PFS) core-forming "A" blocks and a central poly(dimethylsiloxane) (PDMS) corona-forming "B" block has been investigated. The low dispersity (D = 1.05) copolymer, PFS26-b-PDMS584-b-PFS26 (block ratio 1.0:22.5:1.0), was prepared through a combination of living anionic polymerization and end-to-end coupling. The block ratio and dispersity were established by a combination of MALDI-TOF mass spectrometry, 1H NMR, and GPC. Individual 1D fiber-like micelles with looped PDMS coronas were formed in mixed solvents of hexane and decane. Low length-dispersity fiber-like micelles of controlled length were prepared from short seed micelles of PFS26-b-PDMS584-b-PFS26 derived from sonication using the seeded growth method termed living crystallization-driven self-assembly. In addition, seeded growth of blends of both PFS26-b-PDMS584-b-PFS26 and PFS26 homopolymer and of PFS26-b-PDMS584-b-PFS26 and the analogous diblock copolymer PFS26-b-PDMS292 were also explored. Large aggregates with fiber-like protrusions were formed by spontaneous nucleation of the blends of PFS26-b-PDMS584-b-PFS26 and PFS26. High-aspect ratio ribbon-like micelles were formed by adding the blends of PFS26-b-PDMS584-b-PFS26 and PFS26 to the cylindrical PFS26-b-PDMS584-b-PFS26 seeds. In contrast, surprisingly, seeded growth of blends of PFS26-b-PDMS584-b-PFS26 and PFS26-b-PDMS292 or the individual components using seeds of either PFS26-b-PDMS584-b-PFS26 or PFS26-b-PDMS292 showed that growth was only detected in the case of matching of the seed and multiblock copolymer chemistries.

Low-overpotential water oxidation catalyzed by copper(ii) porphyrin to produce O2 in neutral aqueous solution and H2O2 in acidic solution., Low overpotential water oxidation under mild conditions is required for new energy conversion technologies with potential application prospects. Extensive studies on molecular catalysis have been performed to gain fundamental knowledge for the rational designing of cheap, efficient and robust catalysts. We herein report a water-soluble CuII complex of tetrakis(4-N-methylpyridyl)porphyrin (1), which catalyzes the oxygen evolution reaction (OER) in neutral aqueous solutions with small overpotentials: the onset potential of the catalytic water oxidation wave measured at current density j = 0.10 mA cm–2 is 1.13 V versus a normal hydrogen electrode (NHE), which corresponds to an onset overpotential of 310 mV. Constant potential electrolysis of 1 at neutral pH and at 1.30 V versus NHE displayed a substantial and stable current for O2 evolution with a faradaic efficiency of >93%. More importantly, in addition to the 4e water oxidation to O2 at neutral pH, 1 can catalyze the 2e water oxidation to H2O2 in acidic solutions. The produced H2O2 is detected by rotating ring–disk electrode measurements and by the sodium iodide method after bulk electrolysis at pH 3.0. This work presents an efficient and robust Cu-based catalyst for water oxidation in both neutral and acidic solutions. The observation of H2O2 during water oxidation catalysis is rare and will provide new insights into the water oxidation mechanism.

The cytokeratin19 fragment (CYFRA 21-1) is an essential biomarker for non-small cell lung cancer (NSCLC). This work proposed a novel electrochemical immunosensor with a high selective and sensitive detection of CYFRA 21-1via the ring-opening polymerization (ROP) signal amplification strategy. Specifically, 3-mercaptopropionic (MPA) was employed as a cross-linking agent to immobilize cAb on the electrode surface for subsequent specific capture of CYFRA 21-1. After CYFRA 21-1 bound to cAb, the amino groups of them were blocked with acrolein. Then, the sandwich-type compositions were formed via the specific recognition between detection antibody (dAb) and CYFRA 21-1. Finally, the ROP was triggered by the amino group on dAb and the polymers containing a large number of ferrocene electroactive molecules were in situ grown on the electrode surface, thereby outputting a high sensing signal. Under optimal conditions, the fabricated immunosensor showed an ultrasensitive and highly selective with a linear range of 1 pg/mL ∼1 μg/mL, and the detection limit down to 9.08 fg/mL. Furthermore, a bright correlation was obtained for CYFRA 21-1 detection in the clinical serum samples. By merits of its ease of operation, environmental friendliness and low cost, this method had considerable potential application in bioanalytical for the ultrasensitive quantitation of biological molecules.

An electrochemical biosensor for highly sensitive detection of tobacco mosaic virus (TMV) RNA (tRNA) based on click chemistry and photoinduced atom transfer radical polymerization (photoATRP) is developed for the first time. Herein, tRNA is recognized and captured by hairpin DNA immobilized on the gold electrode surface by Au–S self-assembly. Propyl 2-bromoisobutyrate (PBIB), a photoATRP initiator containing an alkyne group, is conjugated to the azide group of hairpin DNA via a Cu(I)-catalyzed azidoalkyl cyclization reaction (CuAAC). Under the irradiation of 470 nm blue light, photoATRP is activated by the photoredox catalyst (eosin Y, EY), resulting in the formation of a large number of electroactive probes (ferrocenylmethyl methacrylate, FMMA), which significantly amplifies the signal. Under the optimal experimental parameters, the strategy has a wide linear detection (0.1 pM–10 nM) (R2 = 0.995) with a limit of detection (LOD) as low as 3.5 fM. In addition, the biosensor also exhibited good selectivity for mismatched bases, excellent stability and reproducibility. Moreover, satisfactory result was achieved when the biosensor was applied to the detection of tRNA from healthy rehmannia total RNA extracts, which demonstrates the great potential of the method in the practical detection of TMV.

It is important to assess the toxic effects posed by soil pollutants toward plants. However, plant toxicology experiments normally involve a considerable amount of manpower, consumables and time. Therefore, the use of metal toxicity prediction models, independent of toxicity tests, is critical. In this study, we investigated the toxicity of different metal ions to wheat using hydroponic experiments. We employed the methods of soft–hard ion grouping, soft–hard ligand theory and K (conditional binding constant based on the biotic ligand model principle) in combination with hydroponic experiments to explore the application of quantitative ion character-activity relationships in predicting phytotoxicity. The results showed that the toxicity of the 19 metal ions tested varied significantly, with EC50 ranging from 0.27 μM to 4463.36 μM. The linear regression relationships between the toxicity of these metal ions and their physicochemical properties were poor (R2 = 0.237–0.331, p

Improving the sensitivity of detection is crucial to monitor biomarker, assess toxicity, and track therapeutic agent. Herein, a sensitivity-improved immunosensor is reported for the first time via functionalized graphene oxide (GO) and a "grafting-to" ring-opening polymerization (ROP) dual signal amplification strategy. Through the ROP reaction using 2-[(4-ferrocenylbutoxy)methyl] oxirane (FcEpo) as the monomer, lots of electroactive tags are linked in situ from multiple initiation sites on the GO surface modified with ethanol amine (GO-ETA), thereby achieving high sensitivity even in the case of trace amounts of tumor markers. The utmost important factor for achieving this high sensitivity is to select functionalized GO as the initiator that contains a large number of repeated hydroxyl functional groups so as to trigger additional ROP reaction. Under the optimal conditions, the high sensitivity and applicability is demonstrated by the use of GO-ETA-mediated ROP-based immunosensor to detect non-small cell lung cancer (NSCLC)-specific biomarker down to 72.58 ag/mL (equivalent to ~6 molecules in a 5 μL sample). Furthermore, the satisfactory results for the determination of biomarkers in clinical serum samples highlighted that this immunosensor holds a huge potential in practical clinical application. This work described an electrochemical immunosensor for ultrasensitive detection of CYFRA 21-1 via the functionalized graphene oxide (GO) and a "grafting-to" ring-opening polymerization (ROP) dual signal amplification strategy, which hold the merits of high sensitivity, applicability, selectivity, efficiency, easy operation and environmental friendliness.

Unclear established standard of bran-fried Atractylodis Rhizoma (BFAR), a commonly used drug in Traditional Chinese Medicine (TCM), compromised its clinical efficacy. In this study, we explored the correlation between color and near-infrared spectroscopy (NIR) feature with content of atractylodin, then established a rapid recognition model for the optimal degree of processing for BFAR preparation. The results of the Pearson analysis indicated that the color values were significantly and positively correlated with atractylodin content. The back propagation artificial neural network algorithm and cluster analysis revealed the color of different BFAR could be accurately divided into three categories; subsequently, the color range for the optimal degrees of stir-frying was established as follows: R[red value (105.79-127.25)], G[green value(75.84-89.64)], B[blue value(33.33-42.73)], L[Lightness (81.26-95.09)].Using NIR, principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and cluster analysis, three types of BFAR were accurately identified. The prediction model of atractylodin content was established using partial least squares regression analysis. The R2 of the validation set was 0.9717 and the root mean square error was 0.026. In the color judgment model, the processing degree of 8 batches of BFAR from the market is inferior. According to the NIR judgment model, the processing degree of all samples from the market is inferior. In conclusion, the best fire degree of BFAR can be identified quickly and accurately based on our established model. It is a potential method for quality evaluation of Chinese Materia Medica processing.

High solid anaerobic digestion (HSAD) was an emerging bioconversion technology which had the advantages of small digester, less digestate and low heating energy. A one-stage anaerobic system in CSTR by inoculating activated sludge of simultaneous propionate degradation and methanogenesis was proposed to improve the high-solid digestion performance and to stabilize the reaction process. Semi-continuous mode was successfully used to perform HSAD from cellulosic ethanol whole stillage at an initial substrate loading of 15.4% (w/w) dry matter content with different OLRs from 1.5 to 5.0 gVS·L−1 d−1 at an HRT of 30 days. The average methane yield during whole digestion reached 349.9 mL⋅gVS−1 with a total VS removal rate of 61.3%. The acclimation mechanism of multifunctional activated sludge was also explored by analyzing the functional property, physiological activity and microbial community structure. The results indicated the feasibility and efficiency of multifunctional activated sludge in a semi-continuous high-solid stirred tank reactor system.

Shape-memory polymers (SMPs), as a class of stimuli-responsive materials, can remember a temporary shape and return to the original shape exposed to an external stimulus, including heat, humidity, light, and electrical and magnetic fields. Electrospun shape-memory polymer fibers (ESMPFs), generally categorized as nano/microfibers with different morphologies and structures, are fabricated via electrospinning. ESMPFs, as promising materials, have potential applications in tissue engineering, drug release, smart cloth, etc. because of their large surface areas, porous structures, and shape-changing properties. In this chapter, we mainly present various SMPs and their composites as well as electrospinning used to fabricate ESMPFs. Moreover, different ESMPF structures, including nonwoven, core-shell, oriented, and particle-filled or -reinforced composites, achieved by adjusting processing parameters, are discussed. Furthermore, actuation methods covering traditional and remote-controlling approaches are also highlighted. Finally, potential applications in many different fields are elaborated along with potential challenges and perspectives.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are persistent organic contaminants of concern to human and environmental health. Several literature reviews and laboratory column experiments have been conducted to determine the transport parameters and to describe the fate of PFAS as they migrate in subsurface environments. However, there are very few case studies focusing on contaminated sites with high-resolution field data. Such studies are crucial for the validation of transport simulation models that have been developed from experimental studies, prior to their broader applications. The key purpose of this research was to evaluate lithological separations of PFAS fractions as they are transported in the vadose zone of a historically (1979) contaminated site where Aqueous Film Forming Foam (AFFF) formulations (3M Lightwater™ and Ansulite™) have been used for fire training exercises. Surface and subsurface soils, and groundwater samples were collected across the site and a total of 29 PFAS compounds were selected as target analytes. The results indicated a distinct profile of PFAS concentration with depth at most of the test bores, exhibiting separation of PFAS as transported in vadose zone soils. Perfluorooctanoic acid (PFOA), Perfluorooctane sulfonic acid (PFOS), and Perfluorohexane sulfonic acid (PFHxS) were the predominant compounds detected in the site samples and they have been found in near-surface soils (

Atractylodes lancea (Thunb.) DC. (AL) is used in traditional Chinese medicine for the treatment of spleen-deficiency syndrome (SDS). Bran-processed Atractylodes lancea (BAL) has been found to be more effective than unprocessed AL. However, the compound in BAL active against SDS remains unclear. The pharmacological efficacy of BAL and its mechanism of action against SDS were investigated by HPLC-ELSD. Candidate compound AA (atractyloside A) in AL and BAL extracts was identified by HPLC-MS analysis. AA was tested in a rat model of SDS in which body weight, gastric residual rate, and intestinal propulsion were measured, and motilin (MTL), gastrin (GAS), and c-Kit were quantified by enzyme-linked immunosorbent assay. Potential targets and associated pathways were identified based on network pharmacology analysis. mRNA expression levels were measured by qRT-PCR and protein expression levels were measured by Western blot analysis and immunohistochemistry. AA increased body weight, intestinal propulsion, MTL, GAS, and c-Kit levels, while decreasing gastric residual volume and intestinal tissue damage, as same as Epidermal Growth Factor Receptor and Proliferating Cell Nuclear Antigen levels. Seventy-one potential pharmacologic targets were identified. Analysis of protein interaction, Gene Ontology (GO) functional analysis, pathway enrichment analysis, and docking and molecular interactions highlighted MAPK signaling as the potential signal transduction pathway. Validation experiments indicated that treatment with AA increased MTL, GAS, ZO-1, and OCLN levels, while reducing AQP1, AQP3, and FGF2 levels. In addition, phosphorylation of p38 and myosin light-chain kinase (MLCK) expression were inhibited. AA improved gastrointestinal function by protecting the intestinal mucosal barrier via inhibition of the p38 MAPK pathway. The results have clinical implications for the therapy of SDS.

The sensitive detection of biomarker cytokeratin fragment antigen 21-1 (CYFRA21-1) is crucial for early diagnosis and screening of non-small cell lung cancer (NSCLC). In this work, an electrochemical biosensor based on Nafion-initiated eATRP has been built for ultrasensitive detection of CYFRA21-1 DNA for the first time. Specifically, peptide nucleic acid (PNA) probes are immobilized onto a gold electrode surface and then hybridized with target DNA to form PNA/DNA heteroduplexes for the subsequent attachment of Nafion by the identified carboxyl–Zr4+–phosphoric acid chemistry. Finally, polymer chains are obtained by linking the monomer of ferrocenylmethyl methacrylate to the PNA/MCH/DNA/Zr4+/Nafion probes via eATRP. Under optimized steady-state conditions, the sensor offers a wide current response for CYFRA21-1 DNA from 10−11 to 10−16 M with a detection limit of 6.42 × 10−17 M. The proposed method of using Nafion as the eATRP initiator exhibits high sensitivity, reproducibility and stability and is a promising strategy for early diagnosis of NSCLC.

Cytokeratin fragment antigen 21-1 (CYFRA 21-1) DNA is perceived as sensitive tumor marker for the diagnosis of non-small cell lung cancer and other tumor. Herein, linear chain poly(e-caprolactone) (PCL) synthesized by ring-opening polymerization is applied to ultrasensitive label-free electrochemical impedance detection system for CYFRA 21-1 DNA. First, thiolated peptide nucleic acid (PNA) is self-assembled into the Au electrode surface through the formation of Au–S bonds, allowing the PNA to act as biomolecular probe and form PNA/DNA heteroduplex with the target DNA via specific hybridization. Then, PCL is conjugated to the immobilized DNA on the electrode via “carboxylate–Zr4+–phosphate” bridges. Finally, the electrochemical response of modified PNA/DNA/Zr4+/PCL electrode is determined by electrochemical impedance method to quantify of CYFRA 21-1 DNA. Under optimal conditions, this method exhibits highly sensitivity with a broad linear range (0.1 fM – 1 nM) (R2 = 0.995) and the limit of detection (LOD) is as low as 10.73 aM, which is equivalent to just 64 molecules in a 10 μL sample. What's more, the high selectivity, good anti-interference, label-free operation, and real-time monitoring in complex samples of the proposed strategy demonstrate its broad application for the early diagnosis and clinical monitoring.

Phytoremediation of metal(loid)s contaminated sites is widely used, while there is scarce of investigation on the metal-enriched biomass waste safely disposal which resulted in risks of causing secondary pollution to the soil and water bodies and even to human health. Thus, this study compared the effects of ashing and pyrolysis treatments on cadmium (Cd) and zinc (Zn) hyperaccumulation plant Sedum plumbizincicola. Chemical speciation, the Toxicity Characteristic Leaching Procedure (TCLP), and diethylenetriamine pentaacetic acid (DTPA) extraction were employed to characterize the bioavailability and leachability of Cd and Zn in the solid residues after pyrolysis and ashing. The risk assessment code (RAC) and potential ecological risk index (RI) were subsequently used to evaluate the risk of the solid residues to the environment. The results showed that both ashing and pyrolysis treatments could transform the bioavailable Cd and Zn in S. plumbizincicola into a more stable form, and the higher the temperature the greater the stablility. Pyrolysis converted a maximum of 80.0% of Cd and 70.3% of Zn in S. plumbizincicola to the oxidisable and residual fractions, compared with ashing which achieved only a ∼42% reduction. The pyrolysis process minimised the risk level of Cd and Zn to the environment based on the RAC and RI assessments. The results of the TCLP test, and DTPA extraction confirmed that the leaching rate and the bioavailable portion of Cd and Zn in the biochars produced by pyrolysis were invariably significantly (p 0.05) lower than the solid residues produced by ashing, and reached the lowest at 650 °C. In other words, pyrolysis was better than ashing for thermal treatment of the metal-enriched hyperaccumulator plant, in view of minimising the bioavailability and leachability of Cd and Zn from the solid residues to the environment. This study provides fundamental data on the choice of treatments for the disposal of metal-enriched plant biomass.

Graphical abstract The cytokeratin fragment antigen 21-1 (CYFRA 21-1) protein is a critical tumor biomarker tightly related to non-small cell lung cancer (NSCLC). Herein, we prepared an effective electrochemiluminescence (ECL) immunosensor for CYFRA 21-1 detection using electrochemically mediated atom transfer radical polymerization (eATRP). The CYFRA 21-1 antigen was fixed on the electrode surface by constructing a sandwich type antibody-antigen-antibody immune system. The sensitivity of ECL was improved by using the eATRP reaction. In this method, eATRP was applied to CYFRA 21-1 detection antibody with N-acryloyloxysuccinimide as functional monomer. This is the first time that ECL and eATRP signal amplification technology had been combined. Under the optimized testing conditions, the immunosensor showed a good linear relation in the range from 1 fg mL−1 to 1 μg mL−1 at a limit of detection of 0.8 fg mL−1 (equivalent to ~ 134 molecules in a 10 μL sample). The ECL immunosensing system based on eATRP signal amplification technology provided a new way for rapid diagnosis of lung cancer by detecting CYFRA 21-1. The paper prepared an electrochemiluminescence biosensor for ultrasensitive detection of CYFRA 21-1 via eATRP signal amplification strategy, which had the advantages of high sensitivity, reproducibility, and held potential prospect for analysis of low-abundance. Supplementary Information The online version contains supplementary material available at 10.1007/s00604-020-04677-x.

Purpose This study aimed to investigate whether magnolin (MGL) possesses the capability of suppressing inflammatory responses that can in turn alleviate osteoarthritis (OA). Methods We investigated the effects of MGL on the viability of rat chondrocytes at concentrations of 5 to 100 µM, and selected 10 µM for further study. We elucidated the molecular mechanisms and signaling pathways mediating these effects via RNA sequencing, qRT-PCR, immunofluorescent staining, and Western blotting techniques. Following this, we established an anterior cruciate ligament (ACL) transection-induced OA rat model, and injected MGL into the knee articular cavities to verify the in vivo anti-inflammatory effects of MGL. Results We found that MGL could recover the TNF-α-induced upregulation of IL-1β, COX2, ADAMTS-5, and MMP-1/3/13 at the gene/protein level, as well as the downregulation of cartilaginous ECM synthesis. Gene expression profiles of different groups identified 49 common differentially expressed genes (DEGs), which were mainly enriched in the structural constituents of the ribosome, the extracellular space, and inflammatory response. The NF-κB pathway was highly enriched, and the expression levels of DEGs associated with it (Nfkbia, Ptgs2, Rela, Tnfrsf1a, Tradd, Traf2) under TNF-α stimulation were reversed by MGL. Further studies proved that MGL simultaneously suppressed the cell nucleus translocation of p65 and the phosphorylation of IκBα. Moreover, in vivo, MGL suppressed cartilage matrix degradation, inhibited MMP-13 expression, and promoted cartilage matrix construction by upregulating SOX9 synthesis. Conclusion MGL demonstrated significant anti-inflammatory bioactivity on chondrocytes by suppressing the activation of NF-κB pathway, which in turn exhibited a significant alleviation of OA.

Nitrogen amendment is known to effectively enhance the bioremediation of hydrocarbon-contaminated soil, but the nitrogen metabolism in this process is not well understood. To unravel the nitrogen metabolic pathway(s) of diesel contaminated soil, six types of nitrogen sources were added to the diesel contaminated soil. Changes in microbial community and soil enzyme genes were investigated by metagenomics analysis and chemical analysis through a 30-day incubation study. The results showed that ammonium based nitrogen sources significantly accelerated the degradation of total petroleum hydrocarbon (TPH) (79-81%) compared to the control treatment (38%) and other non-ammonium based nitrogen amendments (43-57%). Different types of nitrogen sources could dramatically change the microbial community structure and soil enzyme gene abundance. Proteobacteria and Actinobacteria were identified as the two dominant phyla in the remediation of diesel contaminated soil. Metagenomics analysis revealed that the preferred metabolic pathway of nitrogen was from ammonium to glutamate via glutamine, and the enzymes governing this transformation were glutamine synthetase and glutamate synthetase; while in nitrate based amendment, the conversion from nitrite to ammonium was restrained by the low abundance of nitrite reductase enzyme and therefore retarded the TPH degradation rate. It is concluded that during the process of nitrogen enhanced bioremediation, the most efficient nitrogen cycling direction was from ammonium to glutamine, then to glutamate, and finally joined with carbon metabolism after transforming to 2-oxoglutarate.

From smart self-tightening sutures and expandable stents to morphing airplane wings, shape memory structures are increasingly present in our daily life. The lack of methods for synthesizing intricate structures from them on the micron and submicron level, however, is stopping the field from developing. In particular, the methods for the synthesis of shape memory polymers (SMPs) and structures at this scale and the effect of new geometries remain unexplored. Here, we describe the synthesis of shape memory polyurethane (PU) capsules accomplished by interfacial polymerization of emulsified droplets. The emulsified droplets contain the monomers for the hard segments, while the continuous aqueous phase contains the soft segments. A trifunctional chemical cross-linker for shape memory PU synthesis was utilized to eliminate creep and improve the recovery ratios of the final capsules. We observe an anomalous dependence of the recovery ratio with the amount of programmed strain compared to previous SMPs. We develop quantitative characterization methods and theory to show that when dealing with thin-shell objects, alternative parameters to quantify recovery ratios are needed. We show that while achieving 94-99% area recovery ratios, the linear capsule recovery ratios can be as low as 70%. This quantification method allows us to convert from observed linear aspect ratios in capsules to find out unrecovered area strain and stress. The hollow structure of the capsules grants high internal volume for some applications (e.g., drug delivery), which benefit from much higher loading of active ingredients than polymeric particles. The methods we developed for capsule synthesis and programming could be easily scaled up for larger volume applications.

Ethnopharmacological relevance Coptis chinensis Franch (CC) and Zingiber officinale Roscoe (dried ginger; DG) are traditional Chinese medicines. CC can dry dampness, relieve fire and detoxify, and is used to treat gastritis, gastric ulcer, colitis. DG can warm spleen and stomach for dispelling cold, used for the treatment of spleen and stomach deficiency. Both CC and DG are widely used to treat gastrointestinal diseases. CC-DG herb medicine combination originates from Huanglian decoction and Pinellia xiexin decoction in “Shanghan Lun” to comfort the stomach and intestines. CC and DG are used for the treatment of nausea and choking diaphragm which highly associated with gastric cancer clinically in ancient time. Aim of the study This study aimed to investigate the effects and underlying molecular mechanisms of CC-DG combination on gastric cancer. Materials and methods The CC-DG extract was subjected to HPLC analysis. Viability (MTT) and cytotoxicity (CCK8) assays were performed using the SGC7901 and MFC cells. Cell cycle and apoptosis were measured by flow cytometry. The mRNA expression levels were measured by RT-PCR. In vivo anti-tumor activity of CC-DG was assessed in a tumor xenograft model. Results Twelve different proportions of CC-DG were tested for inhibitory effects on gastric cancer cells; CC-DG ratio 1:1 was found most effective. CC-DG administration significantly reduced the cell proliferation, migration, and colony formation, while increased cell apoptosis compared with the control group. CC-DG regulated differentially expressed genes in SGC7901 cells were subjected to pathway enrichment analysis. CC-DG significantly inhibited the cell glucose metabolism, downregulated the expression of LDHA and SLC2A1 genes, and changed the expression of other related genes including ME2, LDHD, LDHB, HIF1A, PKM, Pcx, and Got1. In addition, CC-DG suppressed tumorigenesis and inhibited MKI67 expression in the tumor xenograft model. Conclusions CC-DG inhibited the proliferation, migration, invasion of SGC7901/MFC gastric cells, and in turn, suppressed tumorigenesis by regulating glucose metabolism through regulation of LDHA and SLC2A1 genes.

Cytokeratin fragment antigen 21–1 (CYFRA21-1) is a sensitive marker for detecting non-small cell lung cancer (NSCLC). Ti3C2Tx modified by gold nanoparticles (AuNPs) and molybdenum disulfide (MoS2) were synthesized for the first time to obtain the AuNPs@MoS2@Ti3C2Tx composites, which have large specific surface area and good electrocatalytic properties. A novel electrochemical immunoassay for sensitive detection of CYFRA21-1 was developed by loading a large quantity of secondary antibodies (Ab2) and toluidine blue (TB) on the surface of the material as signal probe, and Nafion-AuNPs mixture as electrode material. When the electrochemical response value of CYFRA21-1 increased linearly within the concentration range of 0.5 pg mL−1–50 ng mL−1, the detection limit can reach as low as 0.03 pg mL−1. In addition, the experimental results showed that the biosensor had the potential to rapidly detect CYFRA21-1 in the complex samples such as patient serum, and had a broad application prospect in the early diagnosis and monitoring of NSCLC.

4D printing adds time as the fourth dimension to 3D printing, which has been actively explored in the biomedical field to develop patient-specific implants due to the ease of manufacturing complex architectures and the capability of dynamic transformations. However, the 4D printing filament used for fused deposition modeling (FDM) is quite limited. Here, 4D printing shape memory polybutylene succinate/polylactic acid (PBS/PLA) composite filament is prepared. The mechanical properties, surface morphology, and shape memory performances of the printed specimens are investigated. Besides, graphene oxide functionalized PBS/PLA shows attractive photothermal properties under near-infrared (NIR) irradiation, and a dynamic, remote, and accurate controlled 4D transformation of a porous scaffold is exhibited. As the first demonstration of 4D printing filament of PBS/PLA for FDM, this work shows its promising application prospects in tissue engineering, photothermal therapy, etc. Additionally, NIR-triggered 4D transformation solves the problem that the conventional thermal-trigger transformation process is difficult to control.

The photocatalytic degradation of a model azo dye acid orange 7 (AO7) by Fe3+-doped TiO2 nanocatalyst has been studied under UV, Visible ( λ >400 nm) and solar light irradiation. The role of hydrogen peroxide to enhance the catalyst’s efficiency was examined. The reaction pathway of complete mineralization was investigated by monitoring the temporal evolution of reaction intermediates and low molecular weight organic acids (LMWOA) as final products in solution. These LMWOAs are oxidized eventually to inorganic ions such a nitrate, sulfate, oxalate etc, which are confirmed using GC–MS, UV–Vis and Ion Chromatographic analyses. The optimized conditions of photocatalytic degradation were obtained for degradation under different light source. The Fe 3 + -doped TiO2 showed high dye degradation efficiency under both UV (100%), visible (100%) and solar light (90%) which distinguishes Fe 3 + -doped TiO2 from materials in literature that are only efficient in particular light source for dye degradation. Furthermore, the Fe 3 + doped titania photocatalysts are stable and can maintain performance up to 6 recycle use. Reaction kinetics for UV and solar light induced degradation followed first order reaction whereas visible light degradation followed a zero-order reaction.

Herein, a series of foldable buckypaper/polyacrylonitrile (BP/PAN) composite films were developed in a facile strategy. This strategy was based on electrospun and vacuum pressurized filtration methods. The composite film had better mechanical properties than pristine BP via interface reinforcing, but not deprived of excellent conductivity. The maximum tensile strength and elongation at break of BP/PAN films were 1.45 and 11.65 times than pristine BP, respectively. Moreover, BP/PAN film had higher electromagnetic interference (EMI) shielding effectiveness (63.7–65 dB) in the Ku band (12–18 GHz) than pristine BP (34.3–42.9 dB), due to interfaces forming between PAN fibers and CNTs. The BP/PAN composite as a promising EMI shielding material could be utilized in military and civil applications, such as flexible antenna, EMI shielding clothes and soft portable electronic products.