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Polycrystalline BiCuSeO oxides are prepared by solid-state reaction followed by pressureless sintering (PLS) and high pressure sintering (HPS) methods. Both the experimental results and the density functional theory calculations indicate that the crystal defect concentrations of BiCuSeO can be reduced under the effect of high pressure. By comparing with the PLS sample, a larger power factor and a lower thermal conductivity can be obtained for the HPS sample. The maximum figure of merit ZT∼0.4 @ 800 K was obtained for the HPS sample, which is about 3 times higher than the PLS sample. These results indicate that the effect of high pressure is beneficial to modifying the microstructure and improving the thermoelectric performance of BiCuSeO oxyselenide. [ABSTRACT FROM AUTHOR]

The Swan gooseAnser cygnoidesis a large threatened goose species in the IUCN Red List, with a natural breeding range in East Asia, migratory and wintering mainly in central and eastern China. In this study, we used PCR-based method to determine the complete mitochondrial genome (mtDNA) of this Anatidae species. The complete mtDNA is a 16,740 bp circular molecule containing 37 typical genes. The gene order is identical with that of the standard avian gene order. All protein-coding genes start with a typical ATG codon except ND5, COI and COII. The termination codon is usually the standard TAA. The non-coding region contains some inter-genic spacers and a control region. [ABSTRACT FROM AUTHOR]

The efficient targeting of drugs to tumor cell and subsequent rapid drug release remain primary challenges in the development of nanomedicines for cancer therapy. Here, we constructed a glucose transporter 1 (GLUT1)-targeting and tumor cell microenvironment-sensitive drug release Glucose-PEG-PAMAM-s-s-Camptothecin-Cy7 (GPCC) conjugate to tackle the dilemma. The conjugate was characterized by a small particle size, spherical shape, and glutathione (GSH)-sensitive drug release. In vitro tumor targeting was explored in monolayer (2D) and multilayer tumor spheroid (3D) HepG2 cancer cell models (GLUT1+). The cellular uptake of GPCC was higher than that in the control groups and that in normal L02 cells (GLUT1−), likely due to the conjugated glucose moiety. Moreover, the GPCC conjugate exhibited stronger cytotoxicity, higher S arrest and enhanced apoptosis and necrosis rate in HepG2 cells than control groups but not L02 cells. However, the cytotoxicity of GPCC was lower than that of free CPT, which could be explained by the slower release of CPT from the GPCC compared with free CPT. Additional in vivo tumor targeting experiments demonstrated the superior tumor-targeting ability of the GPCC conjugate, which significantly accumulated in tumor meanwhile minimize in normal tissues compared with control groups. The GPCC conjugate showed better pharmacokinetic properties, enabling a prolonged circulation time and increased camptothecin area under the curve (AUC). These features contributed to better therapeutic efficacy and lower toxicity in H22 hepatocarcinoma tumor-bearing mice. The GLUT1-targeting, GSH-sensitive GPCC conjugate provides an efficient, safe and economic approach for tumor cell targeted drug delivery. [ABSTRACT FROM AUTHOR]

The efficient targeting of drugs to tumor cell and subsequent rapid drug release remain primary challenges in the development of nanomedicines for cancer therapy. Here, we constructed a glucose transporter 1 (GLUT1)-targeting and tumor cell microenvironment-sensitive drug release Glucose-PEG-PAMAM-s-s-Camptothecin-Cy7 (GPCC) conjugate to tackle the dilemma. The conjugate was characterized by a small particle size, spherical shape, and glutathione (GSH)-sensitive drug release. In vitro tumor targeting was explored in monolayer (2D) and multilayer tumor spheroid (3D) HepG2 cancer cell models (GLUT1+). The cellular uptake of GPCC was higher than that in the control groups and that in normal L02 cells (GLUT1−), likely due to the conjugated glucose moiety. Moreover, the GPCC conjugate exhibited stronger cytotoxicity, higher S arrest and enhanced apoptosis and necrosis rate in HepG2 cells than control groups but not L02 cells. However, the cytotoxicity of GPCC was lower than that of free CPT, which could be explained by the slower release of CPT from the GPCC compared with free CPT. Additional in vivo tumor targeting experiments demonstrated the superior tumor-targeting ability of the GPCC conjugate, which significantly accumulated in tumor meanwhile minimize in normal tissues compared with control groups. The GPCC conjugate showed better pharmacokinetic properties, enabling a prolonged circulation time and increased camptothecin area under the curve (AUC). These features contributed to better therapeutic efficacy and lower toxicity in H22 hepatocarcinoma tumor-bearing mice. The GLUT1-targeting, GSH-sensitive GPCC conjugate provides an efficient, safe and economic approach for tumor cell targeted drug delivery. [ABSTRACT FROM AUTHOR]

The structural properties of pyrochlore Eu2Zr2O7under high pressure have been studied by using Raman spectroscopy andin situangle-dispersive X-ray diffraction (ADXRD). The results of Raman spectra indicate that Eu2Zr2O7undergoes a reversible structural change around 21.2 GPa. The results of Rietveld refinements fromin situADXRD data indicate that the ordered pyrochlore structure (Fd-3m) transforms to the defect-cotunnite structure (Pnma) at 26.5 GPa. The phase transition is irreversible and the transformation process is mainly induced by the accumulations of anti-site defects of the cation sublattice and Frenkel defects on the anion sublattice. Besides, the bonds should play a more important role than the bonds in the process of the phase transformation. [ABSTRACT FROM AUTHOR]

Tree SparrowPasser montanusis an Eurasian distribution passerine bird, which has 9 subspecies. In this study, we determined the complete mitochondrial genome ofPasser montanus saturatus. The mitochondrial DNA is 16,904 bp long with A + T contents of 52.56%. The mitochondrial genome is typical circular that encodes the complete set of 37 genes. All protein-coding genes use the standard mitochondrial initiation codon ATG, except for COI starts with GTG and ND3 starts with ATA. TAN is the most frequent stop codon, and AGN and T– – are also occurred very common. All tRNAs possess the classic clover leaf secondary structure except for tRNASer (AGN)and tRNACys (CUN), which lack the “DHU” stem, only forming a simple loop. [ABSTRACT FROM PUBLISHER]