663 research outputs found

    Not In My State\u27s Indian Reservation -- A Legislative Fix to Close an Environmental Law Loophole

    Get PDF
    For hundreds of years, this continent\u27s Indians shared a spiritual belief that they must respect and protect their Mother Earth above all else. Today, however, many tribes no longer view the environment as a bank of natural resources that they must shield and shelter at any cost. Instead, the economic pressures of the twentieth century-particularly underdevelopment, unemployment, and poverty -are forcing a growing number of Indian tribes to exchange the spiritual view of their once pristine environment for a commercial one. This shift from nurturing nature to exploiting the environment on a growing number of reservations results largely from a legal loophole that permits nonnatives to pollute inside Indian country in ways they could not elsewhere

    IGFBP-3 inhibits Wnt signaling in metastatic melanoma cells.

    Get PDF
    In previous works, we have shown that insulin-like growth factor-binding protein-3 (IGFBP-3), a tissue and circulating protein able to bind to IGFs, decreases drastically in the blood serum of patients with diffuse metastatic melanoma. In agreement with the clinical data, recombinant IGFBP-3 was found to inhibit the motility and invasiveness of cultured metastatic melanoma cells and to prevent growth of grafted melanomas in mice. The present work was aimed at identifying the signal transduction pathways underlying the anti-tumoral effects of IGFBP-3. We show that the anti-tumoral effect of IGFBP-3 is due to inhibition of the Wnt pathway and depends upon the presence of CD44, a receptor protein known to modulate Wnt signaling. Once it has entered the cell, IGFBP-3 binds the Wnt signalosome interacting specifically with its component GSK-3β. As a consequence, the β-catenin destruction complex dissociates from the LRP6 Wnt receptor and GSK-3β is activated through dephosphorylation, becoming free to target cytoplasmic β-catenin which is degraded by the proteasomal pathway. Altogether, the results suggest that IGFBP-3 is a novel and effective inhibitor of Wnt signaling. As IGFBP-3 is a physiological protein which has no detectable toxic effects either on cultured cells or live mice, it might qualify as an interesting new therapeutic agent in melanoma, and potentially many other cancers with a hyperactive Wnt signaling

    THE FUTURE OF WILDFLOWER RESEARCH AND DEVELOPMENT IN SOUTH AFRICA - THE LACHENALIA CASE STUDY

    Get PDF
    This paper reports the socio-economic impact of the lachenalia research program of the ARCRoodeplaat Vegetable and Ornamental Plant Institute (ARC-Roodeplaat) over the period 1965-2010. Data were collected from researchers, the local propagator and the market agent in Holland, using guidelines and questionnaires. A financial and economic analysis were conducted. The results of both were negative, unless increased productivity, early entry into all potential markets and a decreased research gestation period were assumed. Additional impacts were qualitatively assessed. The program contributed to employment creation, the preservation of biodiversity, capacity building and beneficial institutional linkages. The management information generated by the study was used in planning and priority setting at the institute.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

    100+ Gbps/λ 50 km C-Band Downstream PON Using CD Digital Pre-Compensation and Direct-Detection ONU Receiver

    Get PDF
    We experimentally demonstrate a single-wavelength 100 Gbps downstream PON transmission aided by chromatic dispersion digital pre-compensation (CD-DPC) using simple digital signal processing (DSP) finite impulse response (FIR) filters in combination with an IQ Mach-Zehnder modulator (IQ-MZM) at the transmitter side and direct-detection receiver at the optical network unit (ONU). A reach of 50 km over standard single-mode fiber in C-band and an optical distribution network (ODN) loss of 28.5 dB are achieved. Transmission of 50 and 125 Gbps over 50 km of fiber is also tested, achieving 32 dB and 24 dB of ODN loss, respectively. The complexity of the filters, the optimization of the main design parameters, and the tolerance of the CD-DPC to the uncertainty of the exact accumulated link dispersion are analyzed in detail

    1976 Base Data for the Dairy Market Policy Simulator

    Full text link
    A.E. Res. 80-2

    Two-Fiber Self-Homodyne Transmission for Short-Reach Coherent Optical Communications

    Get PDF
    We experimentally evaluate the performance of two-fiber self-homodyne short-reach transmission, showing that it enables the use of DFB laser provided that the optical path mismatch is kept below 1 m for PM-QPSK and 0.5 m for PM-16QAM

    Phase Noise Impact and scalability of self-homodyne short-reach coherent transmission using DFB lasers

    Get PDF
    We investigate on a two-fiber short-reach self-homodyne coherent transmission system without optical amplification, where the same transmission laser is used to generate a modulated signal carrying useful data and a continuous wave signal, which serves as a local oscillator at the receiver side. Target of the work is to determine by experiments and theoretical models under which conditions DFB lasers can be used instead of more expensive ECL lasers. After careful characterization of lasers phase noise in terms of linewidth as a function of the mismatch between the optical paths of the signal and of the local oscillator, the performance of two laser technologies is investigated in the proposed transmission setup, showing that commercial DFB laser can be used, provided that the optical path mismatch between the two fibers is kept below 1.8 meter for 28 GBaud PM-QPSK and 0.8 meter for PM-16QAM modulation format in combination with a soft-decision forward error correction algorithm. After an experimental demonstration, we theoretically investigate the scalability laws of the proposed systems in different configuration flavours

    Exploitation of deployed telecommunication fiber infrastructures for sensing applications

    Get PDF
    The optical fiber infrastructure deployed in our cities to support the metropolitan area networks is exploited for sensing applications, where the optical sensing signals co-propagate together with the telecom traffic. Thanks to a coherent interferometric approach, structural monitoring of buildings can be achieved in deployed passive optical networks based on fiber-to-the-home structure. Moreover, the same technology is experimented in urban fibre ring networks to detect and localize mechanical vibrations or dynamic perturbation
    • …
    corecore