THz Nanoscopy of Metal and Gallium Implanted Silicon

Drude model successfully quantifies the optical constants for bulk matter, but it is not suitable for subwavelength objects. In this paper, terahertz near-field optical microscopy and finite element simulation are used to study gold patches fabricated by Gallium etching. Electron transport is discovered in determining the optical signal strength. The signal from substrate is more complicated and still not fully understood. As the etching area decreases, near-field interaction is not dominated by doping concentration, and a higher signal is observed near connected metals. With the help of simulation, the abnormal enhancement phenomenon is discussed in detail, which lays the foundation for further experimental verification

Pleistocene glacial cycle effects on the phylogeography of the Chinese endemic bat species, Myotis davidii

<p>Abstract</p> <p>Background</p> <p>Global climatic oscillations, glaciation cycles and the unique geographic topology of China have profoundly influenced species population distributions. In most species, contemporary distributions of populations cannot be fully understood, except in a historical context. Complex patterns of Pleistocene glaciations, as well as other physiographic changes have influenced the distribution of bat species in China. Until this study, there had been no phylogeographical research on <it>Myotis davidii</it>, an endemic Chinese bat. We used a combination of nuclear and mitochondrial DNA markers to investigate genetic diversity, population structure, and the demographic history of <it>M. davidii</it>. In particular, we compared patterns of genetic variation to glacial oscillations, topography, and environmental variation during the Pleistocene in an effort to explain current distributions in light of these historical processes.</p> <p>Results</p> <p><it>M. davidii </it>comprises three lineages (MEP, SWP and SH) based on the results of molecular variance analysis (AMOVA) and phylogenetic analyses. The results of a STRUCTURE analysis reveal multi-hierarchical population structure in <it>M. davidii</it>. Nuclear and mitochondrial genetic markers reveal different levels of gene flow among populations. In the case of mtDNA, populations adhere to an isolation-by-distance model, whereas the individual assignment test reveals considerable gene flow between populations. MDIV analysis indicate that the split of the MEP and SWP/SH lineages, and from the SWP and SH lineages were at 201 ka BP and 158 ka BP, respectively. The results of a mismatch distribution analysis and neutrality tests indicate a population expansion event at 79.17 ka BP and 69.12 ka BP in MEP and SWP, respectively.</p> <p>Conclusions</p> <p>The complex demographic history, discontinuous extant distribution of haplotypes, and multiple-hierarchy population structure of <it>M. davidii </it>appear associated with climatic oscillations, topography and eco-environmental variation of China. Additionally, the three regions are genetically differentiated from one another in the entire sample set. The degree of genetic differentiation, based on the analysis of mtDNA and nDNA, suggests a male-mediated gene flow among populations. Refuges were in the MEP, SH and the lower elevations of SWP regions. This study also provides insights for conservation management units (MEP, SWP and SH).</p

Correction: Molecular Heterogeneity of Ewing Sarcoma as Detected by Ion Torrent Sequencing.

[This corrects the article DOI: 10.1371/journal.pone.0153546.]

Quantum Yield and Stability Improvement of Two‐Dimensional Perovskite Via a Second Fluorinated Insulator Layer

Abstract Aiming at the low luminous‐efficiency of two‐dimensional (2D) perovskite, its quantum yield (QY) and stability are effectively improved by a fluorinated second insulator layer 3,4‐difluoroaniline (F2PA) outside of the first insulator 2‐(2,4‐difluorophenyl) ethylamine (FPEA). The QY of perovskite with two insulator layers is improved by 3.4‐time in contrast with its counterpart with one insulator, which originates from the defect suppression and reduction of exciton Bohr radius by the second layer. The optical stability has extended 1.5‐time by the introduced second layer, as an isolation role for inner decomposed products to volatilize and for outer water molecules to penetrate. The perovskite with two insulator layers retained 90% of its initial optical properties in relative humidity 90%–95% atmosphere for 600 h, meanwhile only 50% for its counterpart with one layer. Two‐more fluorine with stronger hydrophobicity can account for this feature. Adding a second insulator layer is an effective strategy to engineer 2D perovskites and push forward its applications in optoelectronic devices

Molecular Heterogeneity of Ewing Sarcoma as Detected by Ion Torrent Sequencing

<div><p>Ewing sarcoma (ES) is the second most common malignant bone and soft tissue tumor in children and adolescents. Despite advances in comprehensive treatment, patients with ES metastases still suffer poor outcomes, thus, emphasizing the need for detailed genetic profiles of ES patients to identify suitable molecular biomarkers for improved prognosis and development of effective and targeted therapies. In this study, the next generation sequencing Ion AmpliSeq^™ Cancer Hotspot Panel v2 was used to identify cancer-related gene mutations in the tissue samples from 20 ES patients. This platform targeted 207 amplicons of 2800 loci in 50 cancer-related genes. Among the 20 tissue specimens, 62 nonsynonymous hotspot mutations were identified in 26 cancer-related genes, revealing the molecular heterogeneity of ES. Among these, five novel mutations in cancer-related genes (<i>KDR</i>, <i>STK11</i>, <i>MLH1</i>, <i>KRAS</i>, and <i>PTPN11</i>) were detected in ES, and these mutations were confirmed with traditional Sanger sequencing. ES patients with <i>KDR</i>, <i>STK11</i>, and <i>MLH1</i> mutations had higher Ki-67 proliferation indices than the ES patients lacking such mutations. Notably, more than half of the ES patients harbored one or two possible ‘druggable’ mutations that have been previously linked to a clinical cancer treatment option. Our results provided the foundation to not only elucidate possible mechanisms involved in ES pathogenesis but also indicated the utility of Ion Torrent sequencing as a sensitive and cost-effective tool to screen key oncogenes and tumor suppressors in order to develop personalized therapy for ES patients.</p></div

Variation in the resting frequency of Rhinolophus pusillus in Mainland China: Effect of climate and implications for conservation

This study describes variation patterns in the constant frequency of echolocation calls emitted at rest and when not flying (“resting frequency” RF) of the least horseshoe bat, Rhinolophus pusillus, on a broad geographical scale and in response to local climatic variables. Significant differences in RF were observed among populations throughout the species range in Mainland China, and this variation was positively and significantly related to climate conditions, especially environmental humidity, but the variability was only weakly associated with geographical distance. Sex dimorphism in the RF of R. pusillus may imply that female and male might keep their frequencies within a narrow range for sex recognition. Moreover, bats adjusted resting frequency to humidity, which may imply partitioning diet by prey size or the influence of rainfall noise. The results indicate that bats adjust echolocation call frequency to adapt to environmental conditions. Therefore, environmental selection shape the diversity of echolocation call structure of R. pusillus in geographically separated populations, and conservation efforts should focus on changes in local climate and effects of environmental noise

Patient information for 20 ES cases.

<p>Patient information for 20 ES cases.</p

Overall alteration distribution of 26 genes annotated by the COSMIC database.

<p>A) Mutation frequency of altered genes in 20 ES samples. The blue bars represent alterations in the ES samples, whereas the red bars represent ES samples without alterations. B) Mutation types of the 26 genes. Yellow bars represent missense mutations, and green bars represent nonsense mutations.</p

Deleterious mutated genes identified in ES samples by IT-PGM.

<p>Deleterious mutated genes identified in ES samples by IT-PGM.</p