20 research outputs found
SED fitting of nearby galaxies in the Herschel Reference Survey
We compute UV to radio continuum spectral energy distributions of 51 nearby galaxies recently observed with SPIRE onboard Herschel and present infrared colours (in the 25-500 μm spectral range). SPIRE data of normal galaxies are well reproduced with a modified black body (β=2) of temperature T≅q 20 K. In ellipticals hosting a radio galaxy, the far-infrared (FIR) emission is dominated by the synchrotron nuclear emission. The colour temperature of the cold dust is higher in quiescent E-S0a than in star-forming systems probably because of the different nature of their dust heating sources (evolved stellar populations, X-ray, fast electrons) and dust grain properties
Lethality and Developmental Delay in Drosophila melanogaster Larvae after Ingestion of Selected Pseudomonas fluorescens Strains
The fruit fly, Drosophila melanogaster, is a well-established model organism for probing the molecular and cellular basis of physiological and immune system responses of adults or late stage larvae to bacterial challenge. However, very little is known about the consequences of bacterial infections that occur in earlier stages of development. We have infected mid-second instar larvae with strains of Pseudomonas fluorescens to determine how infection alters the ability of larvae to survive and complete development.We mimicked natural routes of infection using a non-invasive feeding procedure to study the toxicity of the three sequenced P. fluorescens strains (Pf0-1, SBW25, and Pf-5) to Drosophila melanogaster. Larvae fed with the three strains of P. fluorescens showed distinct differences in developmental trajectory and survival. Treatment with SBW25 caused a subset of insects to die concomitant with a systemic melanization reaction at larval, pupal or adult stages. Larvae fed with Pf-5 died in a dose-dependent manner with adult survivors showing eye and wing morphological defects. In addition, larvae in the Pf-5 treatment groups showed a dose-dependent delay in the onset of metamorphosis relative to control-, Pf0-1-, and SBW25-treated larvae. A functional gacA gene is required for the toxic properties of wild-type Pf-5 bacteria.These experiments are the first to demonstrate that ingestion of P. fluorescens bacteria by D. melanogaster larvae causes both lethal and non-lethal phenotypes, including delay in the onset of metamorphosis and morphological defects in surviving adult flies, which can be decoupled
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Technical implementation in support of the IAEA`s remote monitoring field trial at the Oak Ridge Y-12 Plant
A remote monitoring system (RMS) field trial will be conducted for the International Atomic Energy Agency (IAEA) on highly enriched uranium materials in a vault at the Oak Ridge Y-12 Plant. Remote monitoring technologies are being evaluated to verify their capability to enhance the effectiveness and timeliness of IAEA safeguards in storage facilities while reducing the costs of inspections and burdens on the operator. Phase one of the field trial, which involved proving the satellite transmission of sensor data and safeguards images from a video camera activated by seals and motion sensors installed in the vault, was completed in September 1995. Phase two involves formal testing of the RMS as a tool for use by the IAEA during their tasks of monitoring the storage of nuclear material. The field trial to be completed during early 1997 includes access and item monitoring of nuclear materials in two storage trays. The RMS includes a variety of Sandia, Oak Ridge, and Aquila sensor technologies that provide video monitoring, radiation attribute measurements, and container identification to the on-site data acquisition system (DAS) by way of radio-frequency and Echelon LONWorks networks. The accumulated safeguards information will be transmitted to the IAEA via satellite (COMSAT/RSI) and international telephone lines