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A Tm3+: CaYAlO4 single crystal with disordered structure was prepared using mature Czochralski method. The influence of Tm3+ doping on the structure was studied through PXRD measurement and first-principles calculation. The PXRD pattern shows that the introduce of Tm3+ does not change the structure of CaYAlO4 matrix. Then, the spectroscopic properties of the crystal were studied in detail. The absorption spectrum was recorded. After calculating, the absorption cross-section was 5.48 × 10–20 cm2 at 798 nm and the full width at half maximum (FWHM) of the corresponding absorption band was 22 nm, indicating that the crystal could be effectively pumped by commercial AlGaAs LD. According to the measured emission spectrum, the emission cross-section was 6.14 × 10–20 cm2 at the maximum wavelength, and the FWHM of emission peak was 228 nm. The fluorescence lifetime of Tm3+: 3F4 state in Tm3+: CaYAlO4 was fitted to be 0.239 ms. Based on the gain cross-sections of the Tm3+: 3F4 → 3H6 transition, a tunable range larger than 300 nm is possible when the population inversion level reaches 50%. The above results show that the obtained Tm3+: CaYAlO4 crystal is a promising candidate for ~ 1.8 μm tunable and ultrashort pulse lasers. [ABSTRACT FROM AUTHOR]

As an important resource insect, the Cryptotympana atrata is widely distributed in the eastern and central parts of China. The cicada slough is one of the traditional crude drugs in East Asia, and the main component is polysaccharide, which has the functions of anti-convulsion, relieving asthma and improving lipid metabolism. The parasitoid fungus Cordyceps cicadae, which grows inside the cicada nymphs and forms the fruiting bodies on the surface of the host's carcass, is also known as the "cicada flower" in China. The Cordyceps cicadae is another old, traditional Chinese medicine, which has been used as a tonic and medicine to nourish and regulate human immunity for centuries. For the further development and utilization of the golden cicada, this paper summarized the C. atrata from the aspects of their biological characteristics, distribution area, life cycle, history of edible and medicinal use, edible methods and nutritional compositions; emphatically introduced the edible and potential medicinal value of the C. atrata; and specifically expounded the research progress of its application. As one popular insect food, the prospects for the development of C. atrata have also been put forward, especially in artificial breeding technology, food safety risk assessment and medicinal value utilization. [ABSTRACT FROM AUTHOR]

Pr 0. 7 Sr 0. 3 MnO3 thin films were grown epitaxially on SrTiO3 and LaAlO3 substrates by pulse laser deposition. X-ray diffraction spectra obtained on these films revealed good crystallinity and epitaxy. It was found that the oxygen deficiency and in-plane strain may affect the transport behavior and phase transition near Curie temperature in these Pr 0. 7 Sr 0. 3 MnO3 films. Also, the resistance and metal-insulator phase transition could be modulated significantly by the applied electric currents. The reduction ratio of the peak resistance reached −38% for a bias current I = 5 0 0 μ A, demonstrating a remarkable electroresistance effect. The results are interpreted based on the spatial inhomogeneity related to the coexisted multi-phases with different electronic and magnetic properties. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM), a highly malignant and heterogeneous brain tumor, contains various types of tumor and non-tumor cells. Whether GBM cells can trans-differentiate into non-neural cell types, including mural cells or endothelial cells (ECs), to support tumor growth and invasion remains controversial. Here we generated two genetic GBM models de novo in immunocompetent mouse brains, mimicking essential pathological and molecular features of human GBMs. Lineage-tracing and transplantation studies demonstrated that, although blood vessels in GBM brains underwent drastic remodeling, evidence of trans-differentiation of GBM cells into vascular cells was barely detected. Intriguingly, GBM cells could promiscuously express markers for mural cells during gliomagenesis. Furthermore, single-cell RNA sequencing showed that patterns of copy number variations (CNVs) of mural cells and ECs were distinct from those of GBM cells, indicating discrete origins of GBM cells and vascular components. Importantly, single-cell CNV analysis of human GBM specimens also suggested that GBM cells and vascular cells are likely separate lineages. Rather than expansion owing to trans-differentiation, vascular cell expanded by proliferation during tumorigenesis. Therefore, cross-lineage trans-differentiation of GBM cells is very unlikely to occur during gliomagenesis. Our findings advance understanding of cell lineage dynamics during gliomagenesis, and have implications for targeted treatment of GBMs. [ABSTRACT FROM AUTHOR]