5,686 research outputs found

    Lymphotoxins and cytomegalovirus cooperatively induce interferon-beta, establishing host-virus détente

    Get PDF
    Tumor necrosis factor (TNF)-related cytokines regulate cell death and survival and provide strong selective pressures for viruses, such as cytomegalovirus (CMV), to evolve counterstrategies in order to persist in immune-competent hosts. Signaling by the lymphotoxin (LT)-β receptor or TNF receptor-1, but not Fas or TRAIL receptors, inhibits the cytopathicity and replication of human CMV by a nonapoptotic, reversible process that requires nuclear factor κB (NF-κB)-dependent induction of interferon-β (IFN-β). Efficient induction of IFN-β requires virus infection and LT signaling, demonstrating the need for both host and viral factors in the curtailment of viral replication without cellular elimination. LTα-deficient mice and LTβR-Fc transgenic mice were profoundly susceptible to murine CMV infection. Together, these results reveal an essential and conserved role for LTs in establishing host defense to CMV

    Magnetoroton scattering by phonons in the fractional quantum Hall regime

    Full text link
    Motivated by recent phonon spectroscopy experiments in the fractional quantum Hall regime we consider processes in which thermally excited magnetoroton excitations are scattered by low energy phonons. We show that such scattering processes can never give rise to dissociation of magnetorotons into unbound charged quasiparticles as had been proposed previously. In addition we show that scattering of magnetorotons to longer wavelengths by phonon absorption is possible because of the shape of the magnetoroton dispersion curve and it is shown that there is a characteristic cross-over temperature above which the rate of energy transfer to the electron gas changes from an exponential (activated) to a power law dependence on the effective phonon temperature.Comment: LaTex document, 3 eps figures. submitted to Phys Rev

    Effective Larval Foraging in Large, Low-Diet Environments by Anopheles gambiae

    Get PDF
    Adult mosquito size is constrained by conditions experienced in the larval stage including the amount and quality of diet. The energy expended collecting diet depends partly on its concentration, the water depth, and the mosquito species. In order to better understand these interactions, individualAnopheles gambiaes.s. Giles were cultured to the adult stage in three types of experiments in which one of the following conditions was fixed and the other two were varied: water volume, diet amount, and diet concentration. In addition to survival, days of development to pupation and wing length were determined. The same outcomes were measured in experiments for which special containers were constructed that allowed the detection of chemical and tactile interactions. Larvae were able to develop to adulthood in volumes as great as 30 mL/larva when diet was added at an average rate of only 7 μg/mL/day. The results demonstrate effective foraging in large low-diet volumes far above what had previously been estimated

    Geology of Wabash County

    Get PDF

    Surface Instabilities on Liquid Oxygen in an Inhomogeneous Magnetic Field

    Full text link
    Liquid oxygen exhibits surface instabilities when subjected to a sufficiently strong magnetic field. A vertically oriented magnetic field gradient both increases the magnetic field value at which the pattern forms and shrinks the length scale of the surface patterning. We show that these effects of the field gradient may be described in terms of an ``effective gravity'', which in our experiments may be varied from 1g to 360g.Comment: 4 pages, 5 embedded figures in eps forma

    The ACIGA Data Analysis programme

    Full text link
    The Data Analysis programme of the Australian Consortium for Interferometric Gravitational Astronomy (ACIGA) was set up in 1998 by the first author to complement the then existing ACIGA programmes working on suspension systems, lasers and optics, and detector configurations. The ACIGA Data Analysis programme continues to contribute significantly in the field; we present an overview of our activities.Comment: 10 pages, 0 figures, accepted, Classical and Quantum Gravity, (Proceedings of the 5th Edoardo Amaldi Conference on Gravitational Waves, Tirrenia, Pisa, Italy, 6-11 July 2003
    • …
    corecore