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In this work, the crystal structure, thermal conductivity, as well as dielectric and electrical properties of poly(vinylidene fluoride-co-chlorotrifluoroethylene) [P(VDF-CTFE)] filled with two different carbon nanofillers including exfoliated graphite nanoplates (xGNPs) and multi-walled carbon nanotubes (MWCNTs) have been compared. The xGNPs and the MWCNTs were well dispersed in the P(VDF-CTFE) matrix using a simple solution-blending process. The xGNPs have the ability to induce the large amount of useful polar β and γ crystal phases for P(VDF-CTFE) via the relatively strong interfacial interaction between their functional groups and the dipoles of P(VDF-CTFE), while the MWCNTs only produce the relatively low amount of β crystal phases for P(VDF-CTFE) due to their weak π-dipole interactions with P(VDF-CTFE). It was found that both the electrical conductivity and dielectric properties of xGNPs/P(VDF-CTFE) composite were better than those of MWCNTs/P(VDF-CTFE) composite. The thermal conductivities of xGNPs/P(VDF-CTFE) composites were much higher when compared with those of MWCNTs/P(VDF-CTFE) composites at the same filler content, which is probably owing to the better compatibility between xGNPs and P(VDF-CTFE). For example, the thermal conductivities of xGNPs (5 wt%)/P(VDF-CTFE) composite and MWCNTs (5 wt%)/P(VDF-CTFE) composite were 0.83 W/mK and 0.43 W/mK, respectively. [ABSTRACT FROM AUTHOR]

Siegesbeckia pubescens (SP) has been used as a traditional medicine for the treatment of and inflammatory diseases. However, the activities of SP against hepatocellular carcinoma and the related mechanisms remain unclear. The present study aimed to examine the effects of the essential oil of SP (SPEO) on the proliferation of hepatocellular carcinoma cells and the possible mechanisms. The growth inhibition of HepG2 cells was analyzed by MTT assay. Hoechst 33258 and fluorescence microscopy were utilized to observe the nuclear morphological changes of apoptotic cells. Flow cytometry was used to detect cell apoptosis and cell cycle. The expressions of the target proteins were detected by Western blotting. The results showed that SPEO obviously inhibited the proliferation of HepG2 cells in a dose-dependent manner. SPEO activated a series of apoptotic proteins in HepG2 cells, increasing expression levels of Bax, caspase-3 and caspase-9, and decreasing the bcl-2 expression level. SPEO displayed promising anti-hepatocellular carcinoma activities in vitro, partly by inducing apoptosis in HepG2 cells through activating the mitochondrial pathway. [ABSTRACT FROM AUTHOR]