Purely nonlinear disorder-induced localizations and their parametric amplification

We investigate spatial localization in a quadratic nonlinear medium in the presence of randomness. By means of numerical simulations and theoretical analyses we show that, in the down conversion regime, the transverse random modulation of the nonlinear susceptibility generates localizations of the fundamental wave that grow exponentially in propagation. The localization length is optically controlled by the pump intensity which determines the amplification rate. The results also apply to cubic nonlinearities.Comment: 5 pages, 5 figure

Broadband parametric processes in χ^(2) nonlinear photonic crystals

International audienceWe develop a general model, based on a (2+1)D unidirectional pulse propagation equation, for describing broadband noncollinear parametric interactions in two-dimensional quadratic lattices. We apply it to the analysis of twin-beam optical parametric generation in hexagonally poled LiTaO 3 , gaining further insights into experimental observations

Coincident Fluorescence-Burst Analysis of the Loading Yields of Exosome-Mimetic Nanovesicles with Fluorescently-Labeled Cargo Molecules

The possible targeting functionality and low immunogenicity of exosomes and exosome-like nanovesicles make them promising as drug-delivery carriers. To tap into this potential, accurate non-destructive methods to load them and characterize their contents are of utmost importance. However, the small size, polydispersity, and aggregation of nanovesicles in solution make quantitative characterizations of their loading particularly challenging. Here, an ad-hoc methodology is developed based on burst analysis of dual-color confocal fluorescence microscopy experiments, suited for quantitative characterizations of exosome-like nanovesicles and of their fluorescently-labeled loading. It is applied to study exosome-mimetic nanovesicles derived from animal extracellular-vesicles and human red blood cell detergent-resistant membranes, loaded with fluorescently-tagged dUTP cargo molecules. For both classes of nanovesicles, successful loading is proved and by dual-color coincident fluorescence burst analysis, size statistics and loading yields are retrieved and quantified. The procedure affords single-vesicle characterizations well-suited for the investigation of a variety of cargo molecules and biological nanovesicle combinations besides the proof-of-principle demonstrations of this study. The results highlight a powerful characterization tool essential for optimizing the loading process and for advanced engineering of biomimetic nanovesicles for therapeutic drug delivery

Processing ultrafast optical signals in broadband telecom systems by means of cascaded quadratic nonlinearities

Quadratic optical nonlinearities offer several attractive features for the implementation of ultra-fast, low-noise and transparent telecom devices. Technological progress has dramatically increased their efficiency, driving a steady move towards practical applications. In this talk we shall discuss the use of cascaded quadratic interactions in LiNbO3 integrated devices for pulse diagnostics, format conversion and signal regeneration in ultra-fast multi-wavelength telecom systems

Ultraviolet writing of channel waveguides in proton-exchanged LiNbO₃

We report on a direct ultraviolet (UV) writing method for the fabrication of channel waveguides at 1.55 µm in LiNbO3 through UV irradiation of surface and buried planar waveguides made by annealed proton exchange and reverse proton exchange. A systematic study of the guidance properties as a function of the UV writing conditions is presented

Efficient Wavelength Shifting Over The Erbium Amplifier Bandwidth Via Cascaded Second Order Processes In Lithium Niobate Waveguides

We investigate two schemes for wavelength conversion based on the cascading of two successive second order processes in a quasi-phase-matched lithium niobate channel waveguide. Efficient conversion over the full erbium amplifier bandwidth is possible with a single multi-hundred milliwatt pump laser operating around 1.55 mu m

Processing of telecommunication signals using periodically poled lithium niobate waveguides

This talk reports on processing of high-speed telecommunication signals based on cascaded quadratic nonlinearities in periodically poled lithium niobate (PPLN) waveguides. A strong pump positioned within the acceptance bandwidth of the PPLN device can interact via a cascaded nonlinear process with a second signal, thereby facilitating a switch with a broad optical bandwidth and yielding an output located within the same wavelength band as the inputs. The combination of the PPLN switch with custom-designed optical filtering for pre-conditioning of the signals gives rise to a versatile pulse processing system exhibiting important advantages in terms of compactness and environmental stability. As an example, Fig.1 describes schematically how an optical time-division multiplexed (OTDM) signal can be converted through cascaded second-harmonic generation and difference-frequency generation to a wavelength-division multiplexed (WDM) signal. The experiments that have led to this demonstration will be described in the talk

Charged exciton kinetics in monolayer MoSe2_2 near ferroelectric domain walls in periodically poled LiNbO3_3

Monolayers of semiconducting transition metal dichalcogenides are a strongly emergent platform for exploring quantum phenomena in condensed matter, building novel opto-electronic devices with enhanced functionalities. Due to their atomic thickness, their excitonic optical response is highly sensitive to their dielectric environment. In this work, we explore the optical properties of monolayer thick MoSe$_2$ straddling domain wall boundaries in periodically poled LiNbO$_3$. Spatially-resolved photoluminescence experiments reveal spatial sorting of charge and photo-generated neutral and charged excitons across the boundary. Our results reveal evidence for extremely large in-plane electric fields of 3000\,kV/cm at the domain wall whose effect is manifested in exciton dissociation and routing of free charges and trions toward oppositely poled domains and a non-intuitive spatial intensity dependence. By modeling our result using drift-diffusion and continuity equations, we obtain excellent qualitative agreement with our observations and have explained the observed spatial luminescence modulation using realistic material parameters.Comment: 29 pages, 6 figures, submetted materia

First-Line Chemotherapy for HER-2–Negative Metastatic Breast Cancer Patients Who Received Anthracyclines as Adjuvant Treatment

Learning Objectives After completing this course, the reader will be able to: Discuss the value of retreatment with anthracyclines for HER-2–negative metastatic breast cancer patients who received anthracyclines as adjuvant treatment.Discuss the role of liposomal anthracyclines, taxanes, and combinations without anthracyclines and taxanes, or innovative treatments, including target-based agents.Comment on the weakness and quality of available evidence. Access and take the CME test online and receive 1 AMA PRA Category 1 Credit™ at CME.TheOncologist.co

A Igreja Católica e o Meio Ambiente: Considerações Sobre os Textos-Base da Campanha da Fraternidade a Partir do Concílio Vaticano II

This study aimed at sampling the diversity of ants in environments influenced by diamond mining activities in the Brazilian savannah, providing information on the ant fauna in this region of Mato Grosso.The study was carried out in the city of Poxoréu-MT, Brazil, in a property with diamond mining,where pitfall traps were installed in four different transects per environment: A1 – degraded area by diamond mining A2 – adjacent area to A1 with savannah vegetation with anthropogenic influence, A3 – adjacent area to A2 with anthropized savannah vegetation, bordering with A4 – area with savannah vegetation preserved without anthropogenic changes. Samples were collected bimonthly for a period of one year, and the samples were quantified and identified taking into account their species level in order to allow the application of the diversity indices for each environment. 15 species of ants were sampled among the four environments, being nine species in A1, 13 in A2, 15 in A3 and 12 species in A4, presenting Brachymyrmex patagonicus as the most abundant, foraging in all environments. Diversity indices allow to conclude that A3 has the greatest diversity of species, and conversely the lower dominance, in all environments. However, A1 was the most dominant species of ants due to the lowest diversity. Thus, environmental degradation by diamond mining can affect the composition of ants and their dominance in the savannah vegetation.A Campanha da Fraternidade surgiu durante o Concílio Vaticano II. A sua realização demonstra uma preocupação com o despertar do ser humano para os seus problemas existenciais. Nesse sentido, o objetivo da Campanha da Fraternidade é promover uma reflexão sobre temas importantes para a vida do ser humano, com o intuito de mudar o seu agir, através do princípio do cuidado, diante de algumas realidades que são necessárias para o bom relacionamento e sobrevivência de cada um. O objetivo principal do estudo é identificar a abordagem sobre a questão do meio ambiente nos textos-base das Campanhas da Fraternidade da Igreja Católica do Brasil, à luz da Doutrina Social da mesma, dos documentos do CELAM e CNBB. Os objetivos específicos são: compreender a proposta da ética do cuidado; apresentar as orientações da Igreja em relação ao meio ambiente a partir da Doutrina Social e dos documentos do CELAM e CNBB; identificar as propostas ou ensinamentos sobre o meio ambiente nos textos-base das Campanhas da Fraternidade de 1979 a 2011. A metodologia fundamenta-se nas análises de ampla pesquisa documental, destacando os textos das Campanhas da Fraternidade, as Encíclicas Papais, entre outros documentos da Igreja. Considerando o tamanho e a abrangência da Igreja Católica, sua contribuição para a questão da preservação do meio ambiente é relevante