14 research outputs found
Recommended from our members
Genome-wide association study of Tourette Syndrome
Tourette Syndrome (TS) is a developmental disorder that has one of the highest familial recurrence rates among neuropsychiatric diseases with complex inheritance. However, the identification of definitive TS susceptibility genes remains elusive. Here, we report the first genome-wide association study (GWAS) of TS in 1285 cases and 4964 ancestry-matched controls of European ancestry, including two European-derived population isolates, Ashkenazi Jews from North America and Israel, and French Canadians from Quebec, Canada. In a primary meta-analysis of GWAS data from these European ancestry samples, no markers achieved a genome-wide threshold of significance (p<5 × 10−8); the top signal was found in rs7868992 on chromosome 9q32 within COL27A1 (p=1.85 × 10−6). A secondary analysis including an additional 211 cases and 285 controls from two closely-related Latin-American population isolates from the Central Valley of Costa Rica and Antioquia, Colombia also identified rs7868992 as the top signal (p=3.6 × 10−7 for the combined sample of 1496 cases and 5249 controls following imputation with 1000 Genomes data). This study lays the groundwork for the eventual identification of common TS susceptibility variants in larger cohorts and helps to provide a more complete understanding of the full genetic architecture of this disorder
Visible-to-UV/Violet Upconversion Dynamics in Er3+-Doped Oxyfluoride Nanoscale Glass Ceramics
Visible-to-UV/violet upconversion luminescence is found and studied in oxyfluoride glass ceramics with Er3+ dopant concentrations of 3.5, 6.0, or 12.0 mol%, covering a broad pump-power range. The glass ceramics with doping levels of 3.5 and 6.0 mol% show the strongest upconversion luminescence intensity when compared to both higher doping levels and the respective precursor glasses. A comprehensive analysis of the involved upconversion mechanisms is presented. These materials could be useful to enhance the efficiency of the water-splitting systems by using UV/violet light upconverted from the green and red parts of the solar spectrum, which are an alternative to photovoltaic solar cells. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.status: publishe
Imprinting the nanostructures on the high refractive index semiconductor glass
The centimeter range one-and two-dimensional nanostructures of 70nm pitch have been imprinted by hot pressing with a quartz, silicon or nickel mold, at 240 degrees C, onto the surface of Ge20As20Se14Te46 semiconductor glass. Excellent glass stability of this glass allows multiple re-pressing of the nano-structures. With increasing the Te/Se ratio in the glass formula, the refractive index reaches a value of 3.5 with an option of free electron absorption at elevated temperatures pointing out the use of such nanostructures in submicron and micron scale electronic devices/chips, moth eye structures and photonic crystals. (C) 2011 Elsevier B. V. All rights reserved.status: publishe
Light-matter interactions mediated by nanoscale confinement in plasmonic resonators
Plasmonic resonators are nanosized metallic antennas that convert electromagnetic waves at optical frequencies into localized fields, providing an effective route to couple photons in and out of nanoscale volumes. This unique ability makes these nanostructures excellent tools to study and manipulate light-matter interaction at the nanoscale. The strong coupling of a plasmonic resonator to light, resulting in optical cross-sections of more than 10 times the particle-s physical size, is driven by collective oscillations of the conduction electrons in the metal - the so-called surface plasmon resonances.2 page(s
Energy-transfer luminescence of a zinc oxide/ytterbium oxide nanocomposite
© The Royal Society of Chemistry 2012. A newly structured nanocomposite material based on nanocrystalline ZnO/Yb 2 O 3 has been prepared by thermal decomposition of Yb-doped zinc carbonate hydroxide. Transmission electron microscopy has revealed that the prepared nanopowder consists of ZnO nanocrystals of about 50 to 100 nm size decorated by attached smaller Yb 2 O 3 nanocrystals of about 10 to 15 nm size. X-Ray absorption spectroscopy, in particular XANES and EXAFS, indicate the charge of Yb ions equals to +3 and their coordination is oxygen octahedral with the Yb-O and Yb-Yb interatomic distances the same as in bulk Yb 2 O 3 . Photoluminescence spectroscopy unambiguously proves an efficient excitation energy transfer from the ZnO nanocrystals to the Yb 3+ ions. The energy transfer from the ZnO nanocrystals (absorption range from 250 to 400 nm) to the Yb 3+ ions (emission range from 950 to 1100 nm) has been explained by a model, which considers the quantum cutting effect. The prepared nanocomposite is promising for application as a down-conversion layer for enhanced solar cells.status: publishe
Use of Polyguanidine-Derivatives-Based Biocides for Microbial Growth Inhibition and for the Development of A Novel Polyethylene-Based Composite Material Resistant to the Formation of Multispecies Microbial Biofilms
This study aimed to investigate the dependence of the biocidal activity of polyguanidine (co)polymers on their structure during the formation of biofilms by active PE-degrading cultures of model microorganisms. The Bc-2 copolymer of methacryloyl guanidine hydrochloride (MGHC) and diallyldimethylammonium chloride (DADMAC), which suppressed both the formation of biofilms and the growth of planktonic cultures, exhibited the highest activity. When PE was exposed in tropical soil, the composition of the microbial community on the PE surface differed significantly from that of the community in the surrounding soil. In particular, the proportion of Actinobacteria increased from 7% to 29%, while the proportion of Bacteroidetes decreased from 38% to 8%.
Keywords: biofilms, polyhexamethylene guanidine salts, dynamics of biofilm formation, antibiofilm effect, composite material
Nonlinear Optical Properties of Ag Nanoclusters and Nanoparticles Dispersed in a Glass Host
The nonlinear absorption of Ag atomic
clusters and nanoparticles
dispersed in a transparent oxyfluoride glass host has been studied.
The as-prepared glass, containing 0.15 atom % Ag, shows an absorption
band in the UV/violet attributed to the presence of amorphous Ag atomic
nanoclusters with an average size of 1.2 nm. Upon heat treatment the
Ag nanoclusters coalesce into larger nanoparticles that show a surface
plasmon absorption band in the visible. Open aperture <i>z</i>-scan experiments using 480 nm nanosecond laser pulses demonstrated
nonsaturated and saturated nonlinear absorption with large nonlinear
absorption indices for the Ag nanoclusters and nanoparticles, respectively.
These properties are promising, e.g., for applications in optical
limiting and object’s contrast enhancement