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Khlebtsov N.,Chernyshevsky Saratov State University | Dykman L.,Russian Academy of Sciences
Chemical Society Reviews | Year: 2011

Recent advances in wet chemical synthesis and biomolecular functionalization of gold nanoparticles have led to a dramatic expansion of their potential biomedical applications, including biosensorics, bioimaging, photothermal therapy, and targeted drug delivery. As the range of gold nanoparticle types and their applications continues to increase, human safety concerns are gaining attention, which makes it necessary to better understand the potential toxicity hazards of these novel materials. Whereas about 80 reports on the in vivo biodistribution and in vitro cell toxicity of gold nanoparticles are available in the literature, there is lack of correlation between both fields and there is no clear understanding of intrinsic nanoparticle effects. At present, the major obstacle is the significant discrepancy in experimental conditions under which biodistribution and toxicity effects have been evaluated. This critical review presents a detailed analysis of data on the in vitro and in vivo biodistribution and toxicity of most popular gold nanoparticles, including atomic clusters and colloidal particles of diameters from 1 to 200 nm, gold nanoshells, nanorods, and nanowires. Emphasis is placed on the systematization of data over particle types and parameters, particle surface functionalization, animal and cell models, organs examined, doses applied, the type of particle administration and the time of examination, assays for evaluating gold particle toxicity, and methods for determining the gold concentration in organs and distribution of particles over cells. On the basis of a critical analysis of data, we arrive at some general conclusions on key nanoparticle parameters, methods of particle surface modification, and doses administered that determine the type and kinetics of biodistribution and toxicity at cellular and organismal levels (197 references). © 2011 The Royal Society of Chemistry. Source

Kartashov Y.V.,Russian Academy of Sciences
Optics Letters | Year: 2013

I study vector solitons involving two incoherently coupled field components in periodic parity-time (PT)-symmetric optical lattices. The specific symmetry of the lattice imposes restrictions on the symmetry of available vector soliton states. While all configurations with asymmetric intensity distributions are prohibited, such lattices support multihump solitons with an equal number of "in-phase" or "out-of-phase" spots in two components, residing on neighboring lattice channels. In the focusing medium, only the solitons containing out-of-phase spots in at least one component can be stable, while in the defocusing medium stability is achieved for structures consisting of in-phase spots. Mixed-gap vector solitons with components emerging from different gaps in the lattice spectrum also exist and can be stable in the PT-symmetric lattice. © 2013 Optical Society of America. Source

Dykman L.,Russian Academy of Sciences | Khlebtsov N.,Chernyshevsky Saratov State University
Chemical Society Reviews | Year: 2012

Gold nanoparticles (GNPs) with controlled geometrical, optical, and surface chemical properties are the subject of intensive studies and applications in biology and medicine. To date, the ever increasing diversity of published examples has included genomics and biosensorics, immunoassays and clinical chemistry, photothermolysis of cancer cells and tumors, targeted delivery of drugs and antigens, and optical bioimaging of cells and tissues with state-of-the-art nanophotonic detection systems. This critical review is focused on the application of GNP conjugates to biomedical diagnostics and analytics, photothermal and photodynamic therapies, and delivery of target molecules. Distinct from other published reviews, we present a summary of the immunological properties of GNPs. For each of the above topics, the basic principles, recent advances, and current challenges are discussed. © The Royal Society of Chemistry 2012. Source

Ooo Krasnoe Pole, Russian Academy of Sciences, Ntschran and Ooo Tiokraft | Date: 2012-12-20

The invention relates to the purification and disinfection of air and water. A photocatalytic element consists of sintered glass beads with a pore volume fraction from 20% to 40% and a pore size from 0.1 to 0.5 mm, the surface of which is coated with a titanium dioxide powder, having a specific surface area of 150-400 m

Russian Academy of Sciences | Date: 2012-11-29

The invention relates to processing of data during semantic analysis of text data and building of document semantic models. The method consists of two main steps. In step one, an ontology is extracted from external information sources that contain descriptions of particular domain objects. In step two, the text information in the document is linked to ontology concepts and a document semantic model is built. Electronic resources that may or may not be connected through a hyperlink structure are used as information sources. The technical result is achieved, in particular, by identifying all terms in the document and linking them to ontology concepts, so that each term correlates to one concept (its meaning), and then ranking term meanings by importance to the document.

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