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A new type of multifunctional quantum dot (QD)-polypeptide hybrid nanogel with targeted imaging and drug delivery properties has been developed by metal-affinity driven self-assembly between artificial polypeptides and CdSe-ZnS core-shell QDs. On the surface of QDs, a tunable sandwich-like microstructure consisting of two hydrophobic layers and one hydrophilic layer between them was verified by capillary electrophoresis, transmission electron microscopy, and dynamic light scattering measurements. Hydrophobic and hydrophilic drugs can be simultaneously loaded in a QD-polypeptide nanogel. In vitro drug release of drug-loaded QD-polypeptide nanogels varies strongly with temperature, pH, and competitors. A drug-loaded QD-polypeptide nanogel with an arginine-glycine-aspartic acid (RGD) motif exhibited efficient receptor-mediated endocytosis in αvβ3 overexpressing HeLa cells but not in the control MCF-7 cells as analyzed by confocal microscopy and flow cytometry. In contrast, non-targeted QD-polypeptide nanogels revealed minimal binding and uptake in HeLa cells. Compared with the original QDs, the QD-polypeptide nanogels showed lower in vitro cytotoxicity for both HeLa cells and NIH 3T3 cells. Furthermore, the cytotoxicity of the targeted QD-polypeptide nanogel was lower for normal NIH 3T3 cells than that for HeLa cancer cells. These results demonstrate that the integration of imaging and drug delivery functions in a single QD-polypeptide nanogel has the potential for application in cancer diagnosis, imaging, and therapy.

Since 2000–2001, dengue virus type 1 has circulated in the Pacific region. However, in 2007, type 4 reemerged and has almost completely displaced the strains of type 1. If only 1 serotype circulates at any time and is replaced approximately every 5 years, DENV-3 may reappear in 2012.

Ash fusion temperatures (AFTs) of ashes with different ratio of V2O5 and NiO were investigated under mild reducing (CO/CO2 = 6:4) and oxidizing (air) atmosphere. FactSage, X-ray diffraction (XRD), and scanning electron microscopy/electron dispersive X-ray (SEM-EDX) were applied to determine liquidus temperatures, minerals transformation, and morphology of ash and slag at high temperature. AFTs vary with the content of V2O5, NiO, and VNiO (V2O5 and NiO) and a significant difference was exhibited between reducing and oxidizing atmosphere. Redox reactions of V2O5 and NiO with atmospheres are the major reason for the difference. V2O3 and spinel decrease the melting rate of minerals and increase the AFTs. V2O5 of low liquidus temperature may form eutectic matter with anorthite; so, AFTs significantly decreased under oxidizing atmosphere. Ni aggregation formed regular ball increases AFTs slightly under reducing atmosphere. AFTs with VNiO approach to AFTs with V2O5 because V2O3 is the most refractory minerals under reducing atmosphere and V2O5 forms eutectic matter with spinel under oxidizing atmosphere. The association of refractory minerals and liquid phase influenced the distribution of solid minerals during melting in ash and slag, which was also an important factor to illustrate the influence on AFTs. The correlation between liquidus temperature and AFTs of oxidizing atmosphere for ash containing Ni was established, but the similar correlation for ash containing V was proved not to be feasible. The linear regression relationships of AFTs with the content of V2O5, NiO, and VNiO were established for predicting the fusion temperatures of ash with V and VNi.

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Bats have been identified as natural reservoirs of many viruses, including reoviruses. Recent studies have demonstrated the interspecies transmission of bat reoviruses to humans. In this study, we report the isolation and molecular characterization of six strains of mammalian orthoreovirus (MRV) from Hipposideros and Myotis spp. These isolates were grouped into MRV serotype 1, 2 or 3 based on the sequences of the S1 gene, which encodes the outer coat protein s1. Importantly, we found that three of six bat MRV strains shared high similarity with MRVs isolated from diseased minks, piglets or humans based on the S1 segment, suggesting that interspecies transmission has occurred between bats and humans or animals. Phylogenetic analyses based on the 10 segments showed that the genomic segments of these bat MRVs had different evolution lineages, suggesting that these bat MRVs may have arisen through reassortment of MRVs of different origins.

In this article, a novel AgS nanoparticle-decorated MoS composite (A@M) was synthesized through a facile in situ growth of the monoclinic crystallographic AgS on MoS nanosheets. The A@M composite was used as a catalyst in water splitting which exhibits higher electrocatalytic and photoelectrocatalytic activity than the respective pure MoS and AgS counterparts. Experimental results indicate that the as-prepared A@M composite with an optimal AgS/MoS molar ratio of 16.30% (16%A@M) shows the best catalytic performance with low overpotentials (110 mV for V, 190 mV for onset overpotential, 208 mV for the current density of 20 mA cm), a small Tafel slope (42 mV dec), and a high photocurrent (82 μA cm under an applied potential of 0.4 V). The enhanced electrocatalytic activity is associated with the improved electrical conductivity resulting from the stretched MoS nanosheets and the enriched active sites due to the decorated AgS particles. The formation of a type II heterojunction structure at the interface between AgS and MoS facilitates the separation of photogenerated charge carriers, and thus is responsible for the enhanced photoelectrocatalytic activity and photocatalytic H production rate (628 μmol h g). This work suggests a promising choice to overcome the intrinsic drawbacks of MoS nanostructures for the application in hydrogen evolution.