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Recycling of carbon fiber reinforced composites is important for sustainable development and the circular economy. Despite the use of dynamic chemistry, developing high-strength recyclable CFRPs remains a major challenge due to the mutual exclusivity between the dynamic and mechanical properties of materials. Here, we developed a high-strength recyclable epoxy resin (HREP) based on dynamic dithioacetal covalent adaptive network using diglycidyl ether bisphenol A (DGEBA), pentaerythritol tetra(3-mercapto-propionate) (PETMP), and vanillin epoxy resin (VEPR). At high temperatures, the exchange reaction of thermally activated dithioacetals accelerated the rearrangement of the network, giving it significant reprocessing ability. Moreover, HREP exhibited excellent solvent resistance due to the increased cross-linking density. Using this high-strength recyclable epoxy resin as the matrix and carbon fiber modified with hyperbranched ionic liquids (HBP-AMIM+PF6−) as the reinforcing agent, high performance CFRPs were successfully prepared. The tensile strength, interfacial shear strength (IFSS) and interlaminar shear strength (ILSS) of the optimized formulation (HREP20/CF-HBPPF6) were 1016.1, 70.8 and 76.0 MPa, respectively. In addition, the CFRPs demonstrated excellent solvent and acid/alkali-resistance. The CFRPs could completely degrade within 24 h in DMSO at 140 °C, and the recycled CF still maintained the same tensile strength and ILSS as the original after multiple degradation cycles. [ABSTRACT FROM AUTHOR]

Actinobacillus pleuropneuminiae is the major cause of invasive respiratory disease in swine. To develop an efficient subunit vaccine against pathogens, we designed a dual antigen in a single vaccine that increased the potential for an immune response. We present a dual antigen vaccine (pore-forming domain and nutritional immunity) that induces humoral and cell-mediated T-cell responses, antibodies and TH1 and TH2 cells. Mice were immunized with the dual antigen and individual antigen and then subjected to immune response analysis. A significant antibody response was observed for the dual antigen group. For the cellular immune response, CD4+ and CD8+ T-cell expansion, proinflammatory cytokine (IL-1β, IL-6) and TH2-type cytokine (IL-4, IL-10) gene expression was observed for the dual antigen. Finally, in a challenge test with A. pleuropneumoniae serotype1, the dual antigen, individual antigen and PBS vaccine conferred 100, 40 and 0 % protection. In conclusion, the dual antigen presents critical antigens and increases the efficacy of the vaccine. [ABSTRACT FROM AUTHOR]

Background: Streptococcus suis (S. suis) causes arthritis, meningitis, septicemia, and sudden death in pigs and is also an zoonotic agent for humans. The present study demonstrated that immunization with recombinant Sao-L (surface antigen one-L, rSao-L) protein from a strain of S. suis serotype 2 in pigs was able to increase cross-serotype protection against S. suis serotype 1 and 2 challenge. Since weaning piglets are more susceptible to S. suis infections due to the stresses associated with weaning, prepartum immunization in sows may convey passive immunity to piglets and provide protection. Results: Pregnant sows were immunized with a vaccine containing inactivated S. suis serotype 2 plus rSao as the antigens. Blood samples were collected from their piglets after birth for analysis of antigen-specific antibody titers and levels of various cytokines. Results demonstrated that the titers of S. suis and rSao-specific antibodies were significantly (p < 0.05) higher in the vaccinated piglets in comparison with that of piglets in the control group. The serum levels of interferon (IFN)-β, interleukin (IL)-4, IL-6, and IL-12 were significantly (p < 0.05) increased in piglets born from vaccinated sows when compared to piglets from unvaccinated sows. In addition, piglets were challenged by heterologous and homologous S. suis. All piglets from unvaccinated sows developed severe symptoms of bacteremia, fever, anorexia, depression, and arthritis. On the other hand, piglets from vaccinated sows had significantly (p < 0.05) reduced clinical symptoms and lesion score (by 75 and 81%). Conclusions: Our results revealed that immunizing pregnant sows with the vaccine containing inactivated S. suis bacterin plus rSao as the antigens is able to enhance passive immunity against heterologous and homologous S. suis challenge in their piglets. [ABSTRACT FROM AUTHOR]

Abstract: A series of complicated 9,9-diarylfluorenes (CDAFs) with highly thermal and morphological stability, end-capped oligothiophenes (T) n (PF) m (n =1–3, m =2) and triphenylamines TPA(PF) m (m =1–3), were synthesized via BF3·Et2O-mediated Friedel–Crafts reaction. TPA(PF)2 with bulky 9-phenylfluorene moieties (PFMs) as a morphological stabilizer possesses excellently amorphous solid state with a glass transition temperature (T g) up to 140°C and no T g was observed for TPA(PF)3 with high decomposition temperature up to 499°C. Preliminary characterizations of typical double-layer devices with the configuration of ITO/TPA(PF)3/AlQ3/Mg:Ag show luminance efficiency of ca. 2.25cd/A at 100cd/m2 with a maximum brightness of ca. 8300cd/m2. [Copyright &y& Elsevier]

Background: Survivin is a dual functioning protein. It inhibits the apoptosis of cancer cells by inhibiting caspases, and also promotes cancer cell growth by stabilizing microtubules during mitosis. Since the molecular chaperone Hsp90 binds and stabilizes survivin, it is widely believed that down-regulation of survivin is one of the important therapeutic functions of Hsp90 inhibitors such as the phase III clinically trialed compound 17-AAG. However, Hsp90 interferes with a number of molecules that up-regulate the intracellular level of survivin, raising the question that clinical use of Hsp90 inhibitors may indirectly induce survivin expression and subsequently enhance cancer anti-drug responses. The purpose of this study is to determine whether targeting Hsp90 can alter survivin expression differently in different cancer cell lines and to explore possible mechanisms that cause the alteration in survivin expression. Results: Here, we demonstrated that Hsp90 inhibitors, geldanamycin and 17-AAG, induced the over-expression of survivin in three different human cancer cell lines as shown by Western blotting. Increased survivin mRNA transcripts were observed in 17-AAG and geldanamycin-treated HT-29 and HONE-1 cancer cells. Interestingly, real-time PCR and translation inhibition studies revealed that survivin was over-expressed partially through the up-regulation of protein translation instead of gene transcription in A549 cancer cells. In addition, 17-AAG-treated A549, HONE-1 and HT-29 cells showed reduced proteasomal activity while inhibition of 26S proteasome activity further increased the amount of survivin protein in cells. At the functional level, down-regulation of survivin by siRNA further increased the drug sensitivity to 17-AAG in the tested cancer cell lines. Conclusions: We showed for the first time that down-regulation of survivin is not a definite therapeutic function of Hsp90 inhibitors. Instead, targeting Hsp90 with small molecule inhibitors will induce the over-expression of survivin in certain cancer cell lines and subsequently enhances the ability of cell survival in drug-treated situations. The current study suggests that dual inhibition of Hsp90 and survivin may be warranted. [ABSTRACT FROM AUTHOR]

Abstract: A set of segment polyurethanes were synthesized and were proved to have interconnected, isolated and no hard-segmented domains. It was found that the shape fixity of the polyurethanes decreased with the increase of hard-segment content. The polyurethanes with hard-segment content from 30% to 50% had to be deformed at least to 100% strain to obtain good shape fixity. The segmented polyurethane having no hard-segment domains showed over 90% shape recovery under particular conditions. The segmented polyurethanes having interconnected hard-segment domains showed dramatically decreased shape recovery. The segmented polyurethanes having isolated hard-segment domains showed better shape recovery. When the polyurethanes were heated up to sufficiently high temperature they mostly recovered to their original shape. Stress relaxation would bring decrease to the shape recovery of the polyurethanes, especially to that of the segmented polyurethanes with low hard-segment content of 15% and 20%. For the segmented polyurethanes have isolated hard-segment domains the shape recovery decreased when the deformation amplitude increased from 50% to 200% and stopped decreasing as deformation amplitude increased to 250%. The shape recovery of the segmented polyurethanes could be enhanced nearly to 100% by a pre-deformation treatment. [Copyright &y& Elsevier]

Abstract: A series of vanadium containing mesocellular silica foams (MCF) featuring a well-defined three-dimensional (3D) mesoporosity with ultralarge mesopores were studied with regard to their performance in the oxidative dehydrogenation (ODH) of propane. Catalysts supported on two-dimensional hexagonally ordered siliceous SBA-15 and MCM-41, as well as conventional amorphous silica, were also examined. The dispersity and the nature of the vanadium oxide species were characterized by means of DRIFTS, Raman spectroscopy, DR UV–vis, and H2-TPR. Textural, SAXS, and TEM results indicate that the characteristic mesocellular structural features of MCFs are preserved after the vanadium incorporation. Spectroscopic measurements show that vanadium exists mainly in a tetrahedral environment in dehydrated V-MCF catalysts with V content <4.2 wt%, indicating that a very high surface concentration of isolated or low-polymeric VO x species could be achieved on the present V-MCF systems. The MCF-supported vanadia catalysts exhibit much higher propane conversion and propylene productivity than their conventional V-SBA, V-MCM, and V–SiO2 counterparts in the ODH of propane, demonstrating that apart from the active redox sites, internal molecular transport in mesopores of the catalyst also plays an important role in the gas-phase selective oxidation reactions. [Copyright &y& Elsevier]

Although blog service providers have developed and promoted various interactive functions of their blog platforms, effects of the interactivities on posting behaviour are still vague. Based on past literature, we proposed an information sharing behaviour model involving three types of interactivities, flow and satisfaction. A survey of 586 blog owners demonstrated strong support for the model. The results indicated that flow and satisfaction were positively affected by various types of interactivities and influenced the information sharing behaviour. Furthermore, gender differences in the relationships among interactivities, flow and satisfaction were found. Finally, the implications of this research were discussed. [ABSTRACT FROM AUTHOR]