Spatial resolution effect of light coupling structures

This research project was founded by the National Council for Scientific and Technological Development (CNPq) of Brazil (302397/2014-0), by the National Natural Science Foundation of China (11204386, 11411130117, 11334015), by the Open research project of the State Key Laboratory of Optoelectronic Materials and Technologies, Sun-Yat Sen University of China (OEMT-2015-KF-12, OEMT-2015-KF-13) and by EPSRC of U.K. under grant EP/J01771X/1 (Structured Light). Kezheng Li is also supported by the aboard exchange scholar and international doctoral cooperative project of Sun Yat-sen University.The coupling of light between free space and thin film semiconductors is an essential requirement of modern optoelectronic technology. For monochromatic and single mode devices, high performance grating couplers have been developed that are well understood. For broadband and multimode devices, however, more complex structures, here referred to as "coupling surfaces", are required, which are often difficult to realise technologically. We identify general design rules based on the Fourier properties of the coupling surface and show how they can be used to determine the spatial resolution required for the coupler's fabrication. To our knowledge, this question has not been previously addressed, but it is important for the understanding of diffractive nanostructures and their technological realisation. We exemplify our insights with solar cells and UV photodetectors, where high-performance nanostructures that can be realised cost-effectively are essential.Publisher PDFPeer reviewe

Efficient Silicon Metasurfaces for Visible Light

Dielectric metasurfaces require high refractive index contrast materials for optimum performance. This requirement imposes a severe restraint; either devices have been demonstrated at wavelengths of 700 nm and above using high-index semiconductors such as silicon, or they use lower index dielectric materials such as TiO2 or Si3N4 and operate in the visible wavelength regime. Here, we show that the high refractive index of silicon can be exploited at wavelengths as short as 532 nm by demonstrating a crystalline silicon metasurface with a transmission efficiency of 71% at this wavelength and a diffraction efficiency of 95% into the desired diffraction order. The metasurfaces consist of a graded array of silicon posts arranged in a square lattice on a quartz substrate. We show full 2π phase control, and we experimentally demonstrate polarization-independent beam deflection at 532 nm wavelength. Our results open a new way for realizing efficient metasurfaces based on silicon for the technologically all-important display applications

Anti-angiogenesis therapy in the Vx2 rabbit cancer model with a lipase-cleavable Sn 2 taxane phospholipid prodrug using αvβ3-targeted theranostic nanoparticles

In nanomedicine, the hydrophobic nature of paclitaxel has favored its incorporation into many nanoparticle formulations for anti-cancer chemotherapy. At lower doses taxanes are reported to elicit anti-angiogenic responses. In the present study, the facile synthesis, development and characterization of a new lipase-labile docetaxel prodrug is reported and shown to be an effective anti-angiogenic agent in vitro and in vivo. The Sn 2 phosphatidylcholine prodrug was stably incorporated into the lipid membrane of α(v)β(3)-integrin targeted perfluorocarbon (PFC) nanoparticles (α(v)β(3)-Dxtl-PD NP) and did not appreciably release during dissolution against PBS buffer or plasma over three days. Overnight exposure of α(v)β(3)-Dxtl-PD NP to plasma spiked with phospholipase enzyme failed to liberate the taxane from the membrane until the nanoparticle integrity was compromised with alcohol. The bioactivity and efficacy of α(v)β(3)-Dxtl-PD NP in endothelial cell culture was as effective as Taxol(®) or free docetaxel in methanol at equimolar doses over 96 hours. The anti-angiogenesis effectiveness of α(v)β(3)-Dxtl-PD NP was demonstrated in the Vx2 rabbit model using MR imaging of angiogenesis with the same α(v)β(3)-PFC nanoparticle platform. Nontargeted Dxtl-PD NP had a similar MR anti-angiogenesis response as the integrin-targeted agent, but microscopically measured decreases in tumor cell proliferation and increased apoptosis were detected only for the targeted drug. Equivalent dosages of Abraxane(®) given over the same treatment schedule had no effect on angiogenesis when compared to control rabbits receiving saline only. These data demonstrate that α(v)β(3)-Dxtl-PD NP can reduce MR detectable angiogenesis and slow tumor progression in the Vx2 model, whereas equivalent systemic treatment with free taxane had no benefit

Diversity and phylogeny of basidiomycetous yeasts from plant leaves and soil: Proposal of two new orders, three new families, eight new genera and one hundred and seven new species

Funding Information: We thank Prof. Jian-Yun Zhuang for his advice on nomenclatural matters. We thank Dr. Alexander Idnurm for his kindly providing the sequences and informations of strain IAM13481 and his critical comments for this manuscript, Dr. Aleksey Kachalkin for his sharing the physilogical data of strain KBP Y-5548 and Masako Takashima for her sharing the physilogical data of strain TY-217. We also thank Ana Pontes and Cl?udia Carvalho for editing illustrations of Kondoa myxariophila and for ITS sequencing, respectively. This study was supported by grants No. 31570016 from the National Natural Science Foundation of China (NSFC) and national project on scientific groundwork No. 2014FY210400 from the Ministry of Science and Technology of China. The authors are solely responsible for the content of this work.Nearly 500 basidiomycetous yeast species were accepted in the latest edition of The Yeasts: A Taxonomic Study published in 2011. However, this number presents only the tip of the iceberg of yeast species diversity in nature. Possibly more than 99 % of yeast species, as is true for many groups of fungi, are yet unknown and await discovery. Over the past two decades nearly 200 unidentified isolates were obtained during a series of environmental surveys of yeasts in phyllosphere and soils, mainly from China. Among these isolates, 107 new species were identified based on the phylogenetic analyses of nuclear ribosomal DNA (rDNA) [D1/D2 domains of the large subunit (LSU), the small subunit (SSU), and the internal transcribed spacer region including the 5.8S rDNA (ITS)] and protein-coding genes [both subunits of DNA polymerase II (RPB1 and RPB2), the translation elongation factor 1-α (TEF1) and the mitochondrial gene cytochrome b (CYTB)], and physiological comparisons. Forty-six of these belong to 16 genera in the Tremellomycetes (Agaricomycotina). The other 61 are distributed in 26 genera in the Pucciniomycotina. Here we circumscribe eight new genera, three new families and two new orders based on the multi-locus phylogenetic analyses combined with the clustering optimisation analysis and the predicted similarity thresholds for yeasts and filamentous fungal delimitation at genus and higher ranks. Additionally, as a result of these analyses, three new combinations are proposed and 66 taxa are validated.publishersversionpublishe

Short-Term Effects of Gaseous Pollutants and Particulate Matter on Daily Hospital Admissions for Cardio-Cerebrovascular Disease in Lanzhou: Evidence from a Heavily Polluted City in China

Panel studies show a consistent association between increase in the cardiovascular hospitalizations with air pollutants in economically developed regions, but little evidence in less developed inland areas. In this study, a time-series analysis was used to examine the specific effects of major air pollutants [particulate matter less than 10 microns in diameter (PM10), sulfur dioxide (SO2), and nitrogen dioxides (NO2)] on daily hospital admissions for cardio-cerebrovascular diseases in Lanzhou, a heavily polluted city in China. We examined the effects of air pollutants for stratified groups by age and gender, and conducted the modifying effect of seasons on air pollutants to test the possible interaction. The significant associations were found between PM10, SO2 and NO2 and cardiac disease admissions, SO2 and NO2 were found to be associated with the cerebrovascular disease admissions. The elderly was associated more strongly with gaseous pollutants than younger. The modifying effect of seasons on air pollutants also existed. The significant effect of gaseous pollutants (SO2 and NO2) was found on daily hospital admissions even after adjustment for other pollutants except for SO2 on cardiac diseases. In a word, this study provides the evidence for the detrimental short-term health effects of urban gaseous pollutants on cardio-cerebrovascular diseases in Lanzhou

Case-Based Reasoning Technology Based on TRIZ and Generalized Location Pattern

The case representation is the premise for case retrieval, reuse, revision and storage. The theory of inventive problem solving (TRIZ) is the knowledge-based, systematic approach to innovation and a powerful problem solving methodology. Generalized Location Pattern is a useful tool to realize design automation based on the Function Surface. A new case code representation is established based on both of them, which contains principles information of product innovative design and geometrical information of the assembly or part. The Case-Based Reasoning (CBR) technology for Innovative-Design Automation is illustrated in detail. A prototype computer-aided design (CAD) system has been developed to verify the usefulness and meaning of CBR for Innovative-Design Automation based on TRIZ an