2,590 research outputs found

    THE FEASIBILITY OF RESTORING RUFFED GROUSE INTO ILLINOIS

    Get PDF

    Toxic dinoflagellates and marine mammal mortalities : proceedings of an expert consultation held at the Woods Hole Oceanographic Institution

    Get PDF
    On May 8 and 9, 1989, a consultation of experts was convened at the Woods Hole Oceanographic Institution to discuss the possible link between natural biotoxins and recent mass mortalities of humpback whales and bottlenose dolphins along the eastern coast of the United States. The focus was on the possible role of dinoflagellate toxins in these events. The objectives of the meeting were to review and assess the existing evidence and to recommend research priorities and needs.Funding was provided by NOAA, National Marine Fisheries Service, Woods Hole Oceanographic Institution Coastal Research Center through a grant from the Andrew W. Mellon Foundation and the Woods Hole Oceanographic Institution Sea Grant Program under Grant NA86-D-SW90 (Project R/B - 92 and M/O-2)

    Windborne migration of Auchenorrhyncha (Hemiptera) over Britain

    Get PDF
    Planthoppers (Delphacidae), leafhoppers (Cicadellidae) and froghoppers (Aphrophoridae) (Hemiptera: Auchenorrhyncha) caught during day and night sampling at a height of 200 m above ground at Cardington, Bedfordshire, UK, during eight summers (between 1999 and 2007) were consolidated with high-altitude catches made over England in the 1930s. Comparisons were made with other auchenorrhynchan trapping results from northwest Europe, which were indicative of migration. The migratory abilities in the species concerned were then interpreted in terms of various life-history traits or ecological characteristics, such as ontogenetic, diel and seasonal flight patterns, voltinism, habitat preferences, and host plant affinity. In contrast to some other areas of the world (North America, East Asia), the migratory abilities of most Auchenorrhyncha species in northwest Europe is poorly understood, and thus the present study draws together, and complements, fragmentary information on this topic as a basis for further research

    The circulation near the head of Chesapeake Bay

    Get PDF
    Three-month long current records are examined for a position near the head of the Chesapeake Bay. For time scales longer than 5 days the flow was determined by the strength of the Susquehanna discharge. A major event was Tropical Storm Eloise which occurred near the middle of the observation period and whose influence dominated the current spectra...

    An Evaluation of Audio-Visual and Self-Learning Programs for Agricultural Economic Students

    Get PDF
    Exact date of working paper unknown

    Estimated annual economic impacts from harmful algal blooms (HABs) in the United States

    Get PDF
    Blooms of toxic or harmful microalgae, commonly called "red tides," represent a significant and expanding threat to human health and fisheries resources throughout the United States and the world. Ecological, aesthetic, and public health impacts include: mass mortalities of wild and farmed fish and shellfish, human intoxication and death from the consumption of contaminated shellfish or fish, alterations of marine food webs through adverse effects on larvae and other life history stages of commercial fish species, the noxious smell and appearance of algae accumulated in nearshore waters or deposited on beaches, and mass mortalities of marine mammals, seabirds, and other animals. In this report, we provide an estimate of the economic impacts of HABs in the United States from events where such impacts were measurable with a fair degree of confidence during the interval 1987-92. The total economic impact averaged $49 million per year, with public health impacts representing the largest component (45 percent). Commercial fisheries impacts were the next largest (37 percent of the total), while recreation/tourism accounted for 13 percent, and monitoring/management impacts 4 percent. These estimates are highly conservative, as many economic costs or impacts from HABs could not be estimated.Funding was provided by the National Oceanic and Atmospheric Administration under Grants No. NA46RG0470 and NA90AA-D-SG480, the National Science Foundation under Grant No. OCE-9321244, and the Johnson Endowment of the Marine Policy Center

    Recent Transits of the Super-Earth Exoplanet GJ 1214b

    Full text link
    We report recent ground-based photometry of the transiting super-Earth exoplanet GJ1214b at several wavelengths, including the infrared near 1.25 microns (J-band). We observed a J-band transit with the FLAMINGOS infrared imager and the 2.1-meter telescope on Kitt Peak, and we observed several optical transits using a 0.5-meter telescope on Kitt Peak and the 0.36-meter Universidad de Monterrey Observatory telescope. Our high-precision J-band observations exploit the brightness of the M-dwarf host star at this infrared wavelength as compared to the optical, as well as being significantly less affected by stellar activity and limb darkening. We fit the J-band transit to obtain an independent determination of the planetary and stellar radii. Our radius for the planet (2.61^+0.30_-0.11 Earth radii) is in excellent agreement with the discovery value reported by Charbonneau et al. based on optical data. We demonstrate that the planetary radius is insensitive to degeneracies in the fitting process. We use all of our observations to improve the transit ephemeris, finding P=1.5804043 +/- 0.0000005 days, and T0=2454964.94390 +/- 0.00006 BJD.Comment: Accepted for ApJ Letters, 7 pages, 3 Figures, 2 Table

    Surface Roughness of CoCr and ZrO2 Femoral Heads with Metal Transfer: A Retrieval and Wear Simulator Study

    Get PDF
    Metal transfer to femoral heads may result from impingement against the metallic acetabular shell following subluxation/dislocation, or when metallic debris enters the articulation zone. Such transfers roughen the head surface, increasing polyethylene wear in total hip replacements. Presently, we examined the surface roughness of retrieved femoral heads with metallic transfer. Profilometry revealed roughness averages in regions of metal transfer averaging 0.380 μm for CoCr and 0.294 μm for ZrO2 which were one order of magnitude higher than those from non-implanted controls. Scanning electron microscopy (SEM) revealed adherent transfers on these retrievals, with titanium presence confirmed by electron dispersive spectroscopy. Due to the concern for increased wear, metal transfer was induced on non-implanted heads, which were then articulated against flat polyethylene discs in multidirectional sliding wear tests. Increased polyethylene wear was associated with these specimens as compared to unaltered controls. SEM imaging provided visual evidence that the transfers remained adherent following the wear tests. Pre- and post-test roughness averages exceeded 1 μm for both the CoCr and ZrO2 heads. Overall, these results suggest that metal transfer increases the surface roughness of CoCr and ZrO2 femoral heads and that the transfers may remain adherent following articulation against polyethylene, leading to increased polyethylene wear
    corecore