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Dual-responsive nanocapsules of poly (N-isopropyl acrylamide (NIPAM)-co-acrylic acid (AA)-co-2-hydroxyethylmethacrylate (HEMA)) were synthesized by precipitation polymerization. The dual (temperatu...

In this study, free-radical polymerisation inside MCM-41 mesopores was examined to expose a construction route for a temperature-responsive switchable polymer–silica nanohybrid material with well-defined porosity. Herein, we introduced a vinyl monomer (N-isopropyl acrylamide), a cross-linker, and an AIBN initiator into the palladium nanoparticle incorporated MCM-41 pore channels using the wet-impregnation method followed by in situ radical polymerisation. The structural properties of the synthesised PNIPAM–PdNP–MCM-41 catalyst were analysed by various sophisticated analytical techniques. The temperature switchable nanohybrid catalyst was used to reduce carbonyl compounds to their corresponding alcohols. The catalyst showed high catalytic efficiency and robustness in an aqueous medium at 25 °C. Moreover, the system's polymer layer remarkably boosted catalytic selectivity and activity for carbonyl compound reduction as compared to other controlled catalysts. The suggested switchable system can be employed as a temperature-controllable heterogeneous catalyst and highlights a substitute technique to counter the methodical insufficiency in switchable supported molecular catalytic system production.

Effects of key adhesive parameters such as curing temperature and the amount of adhesive on the out-of-plane compression and fatigue strength of sandwich panels with pyramidal core are experimentally investigated and compared with those of theoretical analysis. It is shown that two different curing temperatures lead to the different liquidity of surplus adhesive squeezed out and then the shapes of spew fillet. Sandwich panels with arc spew fillets have higher compression strength than those with rounded spew fillets. With the increase of the amount of adhesive, the out-of-plane compression strength of those sandwich panels clearly increases firstly and then gradually tends to the theoretical value. By analysis of the S-N fatigue curves of four types of sandwich specimens, the shape of spew fillet, the amount of adhesive and the loading ratios are identified as the key factors governing the compression fatigue properties of truss-cored sandwich structures.

The design of switchable hybrid systems to control the catalytic activity using stimuli-responsive polymers have a great significance in the precise manipulation of the oxidation reactions. Herein, we proposed a novel and facile approach for the synthesis of a dual-responsive silica nanohybrid catalyst by combining the temperature-responsive poly N-isopropylacrylamide (PNIPAM) and pH-responsive poly 4-vinylpyridine (P(4-VP)) with MCM-41 as integrated support via free radical polymerization. The prepared switchable material was decorated with silver nanoparticles (AgNPs) through the co-reduction approach. The X-ray photoelectron spectroscopy (XPS) data confirmed the existence of AgNPs in the zero oxidation state while the dynamic light scattering (DLS) measurements revealed that the material exists in maximum swelling confirmation at low temperature (

To investigate lipopolysaccharide (LPS)-induced changes of cytoskeletal filamentous actin in primary isolated pulmonary microvascular endothelial cells (PMVECs) from wild-type and RAGE knock-out mouse.The lungs of wild-type and RAGE knock-out mice were digested with collagenase type I to obtain endothelial cells purified by anti-CD31-coupled magnetic beads. The PMVEC identified by factor VIII labeling were stimulated with LPS at different concentrations and the changes of filamentous actin were observed by confocal microscopy.The cultured primary cells showed typical endothelial cell phenotype as examined with factor VIII labeling. LPS stimulation caused rearrangement of the cytoskeletal filament F-actin in wild-type mouse PMVECs with stress fiber formation, but such changes were not obvious in RAGE knock-out mouse PMVECs.Mouse PMVECs of a high purity can be obtained by immune magnetic beads. RAGE is involved in LPS-induced destruction of mouse PMVEC cytoskeletons.

Porous TiO2 thin film of photocatalyst was synthesized by charged microemulsion templating. In the process, cationic polystytrene microemulsion (PSTM) was successfully added into the precursor solution of TiO2 (Ti-sol). The factors, such as the charged surfactant species, the amount of PSTM and pH of the solution mixture strongly affect the stability of the solution mixture. TiO2 film containing larger pores in diameter of 20–100 nm was obtained after heat treatment and analyzed by BET and BJH. The addition of PSTM effectively influences crystal structure, specific surface area and morphology of thin films. The crystal particle growth of anatase phase is restrained by PSTM addition, and the addition of PSTM promotes the crystal phase transformation from anatase to rutile phase, as was testified by XRD, AFM and FT-IR. The photocatalytic degradation suggests that the optimal addition of PSTM (the volume ratio of PSTM and Ti-sol being 0.3) can reach a remarkable enhancement of photocatalytic activity of TiO2 films, shown by an increase of almost 66% of the apparent rate constant of degradation.

To investigate the effects of entero-hepatic bile acid circulation on the inter-digestive migrating myoelectrical complex (MMC) in rats.Thirty-two rats were divided into four groups. Three pairs of bipolar silver electrodes were chronically implanted in the antrum, duodenum and jejunum. Three groups of them were ligated around the upper part of common bile duct (CBD). The experiments were performed in conscious and fasting state. The gastrointestinal myoelectrical activity was recorded. Ursodeoxycholic acid (UDCA) and saline were then perfused into stomachs of two groups with CBD obstruction and the effects of them on the MMC were observed.A typical pattern of MMC was observed in normal fasting rats. MMC of antral and duodenal origin disappeared temporarily in earlier stage of CBD obstruction. While MMC of jejunum origin appeared. increased MMC cycle duration was seen after 4 d in rats with CBD obstruction. The MMC after CBD obstruction was characterized by an increased duration of phase II-like activity and decreased duration of phase I and III activity. Perfusion into stomachs with UDCA resulted in a shorter MMC cycle duration and a longer duration of phase III of duodenal origin compared to the normal group.Entero-hepatic bile acid circulation initiates inter-digestive MMC of duodenal origin.