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Vectorial optics with fine inhomogeneous polarization control are highly desired. Metasurfaces have been captivated a promising candidate, but their static post-fabrication geometry largely limits the dynamic tunability. Liquid crystal (LC) is usually employed as an additional index-changing layer together with metasurfaces. Unfortunately, most of the reported LCs only impart a varying but uniform phase on top of that from the metasurface, which we term "scalar" LC optics. Here, we pixelate a single-layer LC to display versatile and tunable vectorial holography, in which the polarization and amplitude could be arbitrarily and independently controlled at varying spatial positions. Furthermore, the subtle and vectorial LC-holography highlights the broadband and electrically-switchable functionalities. Our vectorial LC holography reveals significant opportunities for advanced cryptography, super-resolution imaging, and many other applications. [ABSTRACT FROM AUTHOR]

One of the most important wastewater treatment processes is microelectrolysis, which is extensively used in the primary treatment of pharmaceutical wastewater. In this study, microelectrolysis, as a pretreatment method for the refractory metronidazole pharmaceutical wastewater (MPW) of choice, was improved using the Fenton process and used to remove the chemical oxygen demand (COD) and improve the biochemical capability of MPW. The results showed that the highest COD removal of 40.8% was obtained in the presence of optimized significant factors and the BI (BI = biochemical oxygen demand over five days/COD) of MPW increased from 0.10 to 0.31. In addition, the ultraviolet–visible (UV–Vis) spectroscopy demonstrated that metronidazole in MPW was effectively removed during the combined processes. All these results showed that microelectrolysis combined with Fenton oxidation for MPW was an effective treatment process to achieve higher COD removal and biodegradability improvement. Finally, the breakthrough curves at different flow rates were measured to prove the feasibility of the combined process under optimal conditions. [ABSTRACT FROM AUTHOR]

Polydatin, a natural product, is detected in many daily diets, such as grape juices and peanut. Autophagy regulation is recognized as a new potential strategy for cancer therapy, and previous studies demonstrated that polydatin showed remarkable anti-cancer ability. Nevertheless, the capability of polydatin to induce autophagy and its role in anti-osteosarcoma remains obscure. In this study, we investigated the anticancer effect of polydatin on human osteosarcoma cell line MG-63 and its underlying mechanism. Our results indicated that polydatin significantly inhibited proliferation of MG-63 cells in a dose- and time-dependent manner, and increased their apoptosis and autophagic flux. Further experiments showed that polydatin reduced the expression and phosphorylation (Y705) level of STAT3 (Signal transducer and activator of transcription 3), increased the expression of autophagy-related genes (Atg12, Atg14, BECN1, PIC3K3), and therewith triggered autophagic cell death in MG-63 cells. Of note, the cytotoxicity effect of polydatin was rescued by co-treatment with Colivelin (STAT3 activator), suggesting the dependency of MG-63 cells on STAT3 for survival in this process. Moreover, polydatin-triggered autophagy and apoptosis were remarkably reduced following exposure to autophagy inhibitor 3-methyladenine, while cell viability was increased. In conclusion, these data demonstrated that polydatin induced MG-63 cell death through inducing apoptosis, and autophagy which was mediated via the STAT3 signaling. Therefore, polydatin might be a potential clinical drug in the remedy of osteosarcoma. [ABSTRACT FROM AUTHOR]

Short-chain chlorinated paraffins (SCCPs) are extremely complex technical mixtures of polychlorinated n-alkanes with carbon chain lengths from C to C and chlorine content between 49 and 70 %. SCCPs are under consideration for inclusion in the Stockholm Convention on persistent organic pollutants. SCCPs have been used extensively in industrial production, but little is known about the pollution level in soil environment in China. In this study, levels and distribution of SCCPs in soil samples from Chongming Island were analyzed. Concentrations of total SCCPs in soil samples ranged from 0.42 to 420 ng g, with a median of 9.6 ng g. The ubiquitous occurrence of SCCPs in Chongming Island implied that long-range atmospheric transport and soil-air exchange may be the most important pathways for SCCP contamination in the background area. The localized SCCP contamination could be derived from an unidentified source. Hierarchical cluster analysis indicated that C- and C-congeners were predominant in most soils and C- and C-congeners dominated in the remaining soils. Cl- and Cl-congeners were on the average the most dominant chlorine congeners in nearly all soils. Principal component analysis suggested that the separation of even and odd carbon chain congeners occurred during long-range atmospheric transport and aging in soil in the study area. [ABSTRACT FROM AUTHOR]

Active planar optical devices that can dynamically manipulate light are highly sought after in modern optics and nanophotonics. The geometric phase derived from the photonic spin-orbit interaction provides an integrated strategy. Corresponding elements usually suffer from static functions. Here, we introduce an inhomogeneously self-organized anisotropic medium featured by photo-invertible chiral superstructure to realize geometric phase elements with continuously tunable working spectrum and light-flipped phase profile. Via preprograming the alignment of a cholesteric liquid crystal mixed with a photo-responsive chiral dopant, we demonstrate light-activated deflector, lens, Airy beam and optical vortex generators. Their polychromatic working bands are reversibly tuned in an ultra-broadband over 1000 nm covering green to telecomm region. The chirality inversion triggers facile switching of functionalities, such as beam steering, focusing/defocusing and spin-to-orbital angular momentum conversion. This work offers a platform for advanced adaptive and multifunctional flat optics with merits of high compactness, low loss and broad bandwidth. Optically reconfigurable elements are in demand for future applications. The authors report on the use of chirality-invertible cholesteric liquid crystals to actively manipulate geometric phase and create switchable planar optics elements that perform a variety of functions. [ABSTRACT FROM AUTHOR]