104 research outputs found

    Bloch surface waves-controlled fluorescence emission: coupling into nanometer-sized polymeric waveguides

    Get PDF
    The lateral confinement of Bloch surface waves on a patterned multilayer is investigated by means of leakage radiation microscopy (LRM). Arrays of nanometric polymeric waveguides are fabricated on a proper silicon-nitride/silicon-oxide multilayer grown on a standard glass coverslip. By exploiting the functional properties of the polymer, fluorescent proteins are grafted onto the waveguides. A fluorescence LRM analysis of both the direct and the Fourier image plane reveals that a substantial amount of emitted radiation couples into a guided mode and then propagates into the nanometric waveguide. The observations of the mode are supported by numerical simulations

    Impact of Raman amplification on a 2 Tb/s coherent WDM system

    Get PDF
    The impact of hybrid erbium-doped fiber amplifier (EDFA)/Raman amplification on a spectrally efficient coherent-wavelength-division-multiplexed (CoWDM) optical communication system is experimentally studied and modeled. Simulations suggested that 23-dB Raman gain over an unrepeatered span of 124 km single-mode fiber would allow a decrease of the mean input power of ~6 dB for a fixed bit-error rate (BER). Experimentally we demonstrated 1.2-dB Q-factor improvement for a 2-Tb/s seven-band CoWDM with backward Raman amplification. The system delivered an optical signal-to-noise ratio of 35 dB at the output of the receiver preamplifier providing a worst-case BER of 2 × 10 -6 over 49 subcarriers at 42.8 Gbaud, leaving a system margin (in terms of Q -factor) of ~4 dB from the forward-error correction threshold

    All-optical OFDM and distributed Raman amplification:challenges to enable high capacities and extend reach

    Get PDF
    We review recent advances in all-optical OFDM technologies and discuss the performance of a field trial of a 2 Tbit/s Coherent WDM over 124 km with distributed Raman amplification. The results indicate that careful optimisation of the Raman pumps is essential. We also consider how all-optical OFDM systems perform favourably against energy consumption when compared with alternative coherent detection schemes. We argue that, in an energy constrained high-capacity transmission system, direct detected all-optical OFDM with `ideal' Raman amplification is an attractive candidate for metro area datacentre interconnects with ~100 km fibre spans, with an overall energy requirement at least three times lower than coherent detection techniques

    Innovative In Situ and Ex Situ Conservation Strategies of the Madonie Fir Abies nebrodensis

    Get PDF
    Abies nebrodensis (Lojac.) Mattei is an endemic species of the north-west of Sicily located in an 84 ha area in the Madonie Regional park. The current population is limited to 30 relic adult trees and a fluctuating number of juveniles of natural regeneration. The species is defined as “Critically Endangered” in the Italian list of threatened plants and is classified as CR-D in the 2000 IUCN Red List of Threatened Species. This article reports the key action undertaken by the LIFE4FIR project aimed at preserving A. nebrodensis, and the results obtained so far in three years of activity. OpenArrays SNPs genotyping revealed a high rate of inbreeding in the natural population and that the adult trees are genetically related. Controlled cross-pollination was consequently performed to increase the genetic variability of the progeny. Outbred offspring are currently being grown in the nursery. Reforestation has been planned by using 4000 selected outbred seedlings in 10 areas within Madonie Park to create re-diffusion cores. Support and protection of the relic population have been implemented through regular phytosanitary surveys, as well as new fencing and video surveillance systems against grazing and wild herbivores. A seedbank and cryobank for the long-term germplasm conservation have been established.European Union LIFE18/NAT/IT/00016

    Psychometric testing of three Chinese online-related addictive behavior instruments among Hong Kong university students

    Get PDF
    Objective: To validate the Chinese version of the nine-item Internet Gaming Disorder Scales- Short Form (IGDS-SF9), Bergen Social Media Addiction Scale (BSMAS), and Smartphone Application-Based Addiction Scale (SABAS) among Hong Kong university students. Participants and Methods: Participants aged between 17 and 30 years participated in the present study (n=307; 32.4% males; mean [SD] age=21.64 [8.11]). All the participants completed the IGDS-SF9, BSMAS, SABAS, and the Hospital Anxiety and Depression Scale (HADS). Confirmatory factor analyses (CFAs) were used to examine the factorial structures and the unidimensionality for IGDS-SF9, BSMAS, and SABAS. Results: CFAs demonstrated that the three scales were all unidimensional with satisfactory fit indices: comparative fit index = 0.969 to 0.992. In addition, the IGDS-SF9 and BSMAS were slightly modified based on the modification index in CFA. Conclusions: The Chinese IGDS-SF9, BSMAS, and SABAS are valid instruments to assess the addiction levels of internet-related activities for Hong Kong university students

    Surface nanophotonics with Bloch waves on dielectric multilayers

    Get PDF
    Planar mutilayers sustaining either TE or TM polarized Bloch Surface Waves (BSWs) offer new opportunities for management of light at the nanoscale. We will discuss how BSWs can be exploited in guiding and confining light on nanometric relieves, enhancing fluorescence emission and providing additional features for plasmonic nano-antennas

    Co-administration With the Pharmacological Chaperone AT1001 Increases Recombinant Human α-Galactosidase A Tissue Uptake and Improves Substrate Reduction in Fabry Mice

    Get PDF
    Fabry disease is an X-linked lysosomal storage disorder (LSD) caused by mutations in the gene (GLA) that encodes the lysosomal hydrolase α-galactosidase A (α-Gal A), and is characterized by pathological accumulation of the substrate, globotriaosylceramide (GL-3). Regular infusion of recombinant human α-Gal A (rhα-Gal A), termed enzyme replacement therapy (ERT), is the primary treatment for Fabry disease. However, rhα-Gal A has low physical stability, a short circulating half-life, and variable uptake into different disease-relevant tissues. We hypothesized that coadministration of the orally available, small molecule pharmacological chaperone AT1001 (GR181413A, 1-deoxygalactonojirimycin, migalastat hydrochloride) may improve the pharmacological properties of rhα-Gal A via binding and stabilization. AT1001 prevented rhα-Gal A denaturation and activity loss in vitro at neutral pH and 37 °C. Coincubation of Fabry fibroblasts with rhα-Gal A and AT1001 resulted in up to fourfold higher cellular α-Gal A and ~30% greater GL-3 reduction compared to rhα-Gal A alone. Furthermore, coadministration of AT1001 to rats increased the circulating half-life of rhα-Gal A by >2.5-fold, and in GLA knockout mice resulted in up to fivefold higher α-Gal A levels and fourfold greater GL-3 reduction than rhα-Gal A alone. Collectively, these data highlight the potentially beneficial effects of AT1001 on rhα-Gal A, thus warranting clinical investigation

    BAG1: The Guardian of Anti-Apoptotic Proteins in Acute Myeloid Leukemia

    Get PDF
    BCL2 associated Athano-Gene 1 (BAG1) is a multifunctional protein that has been described to be involved in different cell processes linked to cell survival. It has been reported as deregulated in diverse cancer types. Here, BAG1 protein was found highly expressed in children with acute myeloid leukemia at diagnosis, and in a cohort of leukemic cell lines. A silencing approach was used for determining BAG1's role in AML, finding that its down-regulation decreased expression of BCL2, BCL-XL, MCL1, and phospho-ERK1/2, all proteins able to sustain leukemia, without affecting the pro-apoptotic protein BAX. BAG1 down-regulation was also found to increase expression of BAG3, whose similar activity was able to compensate the loss of function of BAG1. BAG1/BAG3 co-silencing caused an enhanced cell predisposition to death in cell lines and also in primary AML cultures, affecting the same proteins. Cell death was CASPASE-3 dependent, was accompanied by PARP cleavage and documented by an increased release of pro-apoptotic molecules Smac/DIABLO and Cytochrome c. BAG1 was found to directly maintain BCL2 and to protect MCL1 from proteasomal degradation by controlling USP9X expression, which appeared to be its novel target. Finally, BAG1 was found able to affect leukemia cell fate by influencing the expression of anti-apoptotic proteins crucial for AML maintenance
    corecore