Search

The unbalance of tourism development and comparative superiority of the tea industry brings new opportunities to the poor groups along Lijiang River Valley for improving their livelihoods. From the perspective of sustainable livelihoods, we analyze the problems in tea farmers' livelihoods, such as lack of fund, low capacity in price negotiation, and high cost of resisting various risks. Recommendations are put forward for tea farmers to improve their livelihoods through ways of enterprise cooperation, innovative marketing, brand cultivation, industrial integration and so on. [ABSTRACT FROM AUTHOR]

The effects of two types of carbon blacks (CBs), N990 and Vulcan XC-72, on the mechanical properties and thermal conductivity of filled silicone rubber (SR) were investigated. It was found that the addition of CB particles increased the thermal conductivity, the thermal stability and the tensile strength of the silicone rubber composites. The scanning electron microscope showed that Vulcan XC-72 of higher structure was more liable to form conductive network within the matrix, and the thermal conductivity of the composites filled by Vulcan XC-72 was superior to that of the composites filled by N990 at the same filler loading. The Agari model and the Payne effect were used to explain the influence of N990 and Vulcan XC-72 on the formation of thermal conductive networks. Furthermore, Vulcan XC-72 also had better enhancing effects on the mechanical properties and the electrical conductivity of the composites. It was notable that at the high filler contents, silicone rubber filled with N990 also possessed good general properties. [ABSTRACT FROM AUTHOR]

Multi-drug-resistant tuberculosis (MDR-TB) is a huge public health problem. The treatment regimen of MDR-TB requires prolonged chemotherapy with multiple drugs including second-line anti-TB agents associated with severe adverse effects. Capreomycin, a polypeptide antibiotic, is the first choice of second-line anti-TB drugs in MDR-TB therapy. It requires repeated intramuscular or intravenous administration five times per week. Pulmonary drug delivery is non-invasive with the advantages of local targeting and reduced risk of systemic toxicity. In this study, inhaled dry powder formulation of capreomycin targeting the lung was developed using spray drying technique. Among the 16 formulations designed, the one containing 25% capreomycin (w/w) and spray-dried at an inlet temperature of 90 °C showed the best overall performance with the mass median aerodynamic diameter (MMAD) of 3.38 μm and a fine particle fraction (FPF) of around 65%. In the pharmacokinetic study in mice, drug concentration in the lungs was approximately 8-fold higher than the minimum inhibitory concentration (MIC) (1.25 to 2.5 µg/mL) for at least 24 h following intratracheal administration (20 mg/kg). Compared to intravenous injection, inhaled capreomycin showed significantly higher area under the curve, slower clearance and longer mean residence time in both the lungs and plasma.

Synthesis conditions and performance of a novel alite-strontium calcium sulfoaluminate cement are reported: the clinker composition is modified from that of Portland cement. The mineral composition and the microstructure of the clinker were analysed by X-ray diffraction (XRD) analysis, scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDS) and lithofacies. The results show that strontium calcium sulfoaluminate and the minerals of Portland cement clinker can coexist in one clinker system. The optimal composition of alite-strontium calcium sulfoaluminate clinker is as follows: strontium calcium sulfoaluminate 9% (mass %), C3S 59·35%, C2S 14·14%, C3A 7.50%, C3AF 10·00%. The content of strontium calcium sulfoaluminate produced during the sintering process at 13808°C is high. The compressive strength of the cement prepared under the testing conditions reaches 30·5 MPa, 58·4 MPa and 122·2 MPa at 1 day, 3 days and 28 days curing ages, respectively. [ABSTRACT FROM AUTHOR]

Population control has become a major problem in many wildlife species. Sterility control through contraception has been proposed as amethod for reducing population size. In this paper, the single specieswith sterility control and feedback controls is considered. Sufficient conditions are obtained for the permanence and extinction of the system. The results show that the feedback controls do not influence the permanence of the species. [ABSTRACT FROM AUTHOR]

UV absorbent was blended with virgin carbon black to prepare modified carbon black (m-CB) using a solid phase modification. The mixed solutions of poly(ethylene terephthalate) (PET)/CB and PET/m-CB were coated on glass substrates to fabricate light screening films. Scanning electron microscopy (SEM) showed that m-CB had better dispersibility than CB in PET matrix. Nonisothermal crystallization kinetics of virgin PET, PET/CB, and PET/m-CB films were investigated by differential scanning calorimetry (DSC). The data were described by a modified Avrami model. The results showed CB and m-CB acted as nucleating agents and increased the crystallization rate of PET. But due to the low crystallization capacity of copolymerized PET (co-PET) matrix, the nucleating effects were not as obvious as expected. The addition of 4 wt% m-CB improved the UV screening ability of the composite film significantly and just slightly increased their haze. [ABSTRACT FROM AUTHOR]

A class of implicit multivalued vector equilibrium problems is studied. By using the generalized Fan-Browder fixed point theorem, some existence results of solutions for the implicit multivalued vector equilibrium problems are obtained under some suitable assumptions. Moreover, a stability result of solutions for the implicit multivalued vector equilibrium problems is derived. These results extend and unify some recent results for implicit vector equilibrium problems, multivalued vector variational inequality problems, and vector variational inequality problems. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the nucleation effect of modified carbon black on the crystallization of poly(lactic) acid (PLA). The researchers used differential scanning calorimetry (DSC) analysis to investigate the nonisothermal crystallization of PLA, PLA/carbon black (CB) and PLA/modified carbon black (MCB) composites. It explains the applications and use of carbon black (CB). The study confirms that MCB advances nuclei density and promotes the crystallization rate of the PLA matrix.

Abstract  A novel method was employed to modify the surface of carbon black (CB) by an organic small molecule in a Haake Rheomix mixer. Jeziorny equation, the Ozawa model and Mo equation were employed to describe the non-isothermal crystallization process of poly (lactic acid) (PLA), PLA/CB and PLA/modified carbon black (MCB) composites. It is found that the Ozawa model fail to describe the non-isothermal crystallization process for PLA and its composites, while Jeziorny equation and Mo’s theory provide a good fitting. The comparison of crystallization kinetics between PLA/MCB and PLA through Lauritzen–Hoffman model indicates that there appears a transition from regimes II to III in PLA and PLA/MCB. The fold surface free energy σ e of PLA/MCB composite is higher than that of neat PLA, implying that the existence of nucleating agent is unfavorable for the regular folding of the molecule chain. [ABSTRACT FROM AUTHOR]

Abstract  Polystyrene (PS)/carbon black (CB) composite microspheres were prepared using a modified CB, which was prepared by blending CB with a hindered phenol antioxidant Irganox 1330 in an internal mixer. Scanning electron microscopy indicated that the modified CB adsorbed on the surface of PS microspheres homogenously to form a raspberry-like morphology composite. The non-covalent binding of Irganox 1330 on the surface of PS microsphere was observed from the UV-Vis absorption spectrum in ethanol, while the fluorescence of PS was almost totally quenched by the binding of Irganox 1330. These results implied there were aromatic interactions between Irganox 1330 and the PS microspheres, which played a crucial role in the formation of composite microspheres. [ABSTRACT FROM AUTHOR]

The encapsulation of poly (n-butyl acrylates) (PBA) onto carbon black (CB) surface v/a ultrasonic irradiation initiating emulsion polymerization was investigated. The results showed that the route performed at ambient temperature can efficiently prepare PBA encapsulated CB as proved by the aggregation of PBA encapsulated CB in the precipitator of PBA. The surface properties of CB coated with PBA were analyzed by FT-IR and XPS. The content of PBA encapsulated on the CB surface reaches 11.87% determined by TGA. Compared with the conventional chemical modification of CB, it was found that the particle size of CB obtained by the present approach can be controlled, and dynamic light scattering results quantified that CB particles with narrower size distribution and smaller size were obtained. The PBA encapsulated CB can be dispersed uniformly in the polymer matrix. [ABSTRACT FROM AUTHOR]

Multiple modifications to the structure of curcumin have been investigated with an aim to improve its potency and biochemical properties. Previously, we have synthesized a series of curcumin analogs. In the present study, the anticancer effect of 2-pyridyl cyclohexanone, one of the curcumin analogs, on esophageal carcinoma Eca109 and EC9706 cell lines and its molecular mechanisms were investigated. 2-Pyridyl cyclohexanone inhibited the proliferation of Eca109 and EC9706 cells by inducing apoptosis as indicated by morphological changes, membrane phospholipid phosphatidylserine ectropion, caspase 3 activation, and cleavage of poly(ADP-ribose) polymerase. Mechanistic studies indicated that 2-pyridyl cyclohexanone disrupted mitochondrial membrane potential, disturbed the balance of the Bcl-2 family proteins, and triggered apoptosis via the mitochondria-mediated intrinsic pathway. In 2-pyridine cyclohexanone-treated cells, the phosphorylation levels of JAK2 and STAT3 were dose-dependently decreased and p38 and p-ERK signals were notably activated in a dose-dependent manner. Moreover, we found that the addition of S3I-201, a STAT3 inhibitor, led to a decreased expression level of Bcl-2 in Eca109 cells. The chromatin immunoprecipitation assay demonstrated that STAT3 bound to the promoter of Bcl-2 in the Eca109 cells. Furthermore, the mutation of four STAT3 binding sites (−1733/−1723, −1627/−1617, −807/−797, and −134/−124) on the promote of Bcl-2 gene alone attenuated the transcriptional activation of STAT3. In addition, down-regulation of STAT3 resulted in less of transcriptional activity of STAT3 on Bcl-2 expression. These data provide a potential molecular mechanism of the apoptotic induction function of 2-pyridyl cyclohexanone, and emphasize its important roles as a therapeutic agent for esophageal squamous carcinoma.

Gene expression is precisely regulated during the inflammatory response to control infection and limit the detrimental effects of inflammation. Here, we profiled global mRNA translation dynamics in the mouse primary macrophage-mediated inflammatory response and identified hundreds of differentially translated mRNAs. These mRNAs’ 3’UTRs have enriched binding motifs for several RNA-binding proteins, which implies extensive translational regulatory networks. We characterized one such protein, Zfp36, as a translation repressor. Using primary macrophages from a Zfp36-V5 epitope tagged knock-in mouse generated by CRISPR/Cas9-mediated genome editing, we found that the endogenous Zfp36 directly interacts with the cytoplasmic poly(A)-binding protein. Importantly, this interaction is required for the translational repression of Zfp36’s target mRNAs in resolving inflammation. Altogether, these results uncovered critical roles of translational regulations in controlling appropriate gene expression during the inflammatory response and revealed a new biologically relevant molecular mechanism of translational repression via modulating the cytoplasmic poly(A)-binding protein.

In order to expand the application of polysaccharide coatings in the preservation of aquatic products, sandwich-type composite coatings were prepared using konjac glucan (KGM) and sodium alginate (SA) as coating substrates and thymol (Thy) and ε-poly-L-lysine hydrochloride (ε-PL) as antimicrobial agents and their effects on protein oxidation in fresh salmon fillets were studied during storage at 4 ℃. The results showed that the solubility, sulfhydryl content and Ca2+-ATPase activity of myofibrillar protein in the composite coating treated fillets increased, and the carbonyl content and surface hydrophobicity of myofibrillar protein (MP) decreased remarkably compared with those treated with sterile water after the same storage period. In addition, the tertiary and secondary structures of myofibrillar protein in the composite coating treated group was more complete. In the late storage period, the protein oxidation indexes of salmon fillets treated with KGM/SA + ε-PL/KGM + Thy composite coating were better than those of the samples treated with KGM/SA + ε-PL/KGM and KGM/SA + Thy/KGM composite coatings after the same storage period. Therefore, in the sandwich-type KGM/SA/KGM composite coating, ε-PL and Thy could act synergistically to delay protein oxidation and denaturation. The results of this study can provide technical guidance for the application of edible coatings in aquatic product preservation.