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Hirschberg P.A.,National Oceanic and Atmospheric Administration | Abrams E.,AccuWeather Inc. | Bleistein A.,National Oceanic and Atmospheric Administration | Bua W.,COMET | And 12 more authors.
Bulletin of the American Meteorological Society | Year: 2011

The AMS Board on Enterprise Communication has set goals and prepared a road map of tasks for enterprise sectors, led by the National Weather Service, to work on together to make uncertainty information integral to hydrometeorological forecasts. The Plan defines a vision, strategic goals, roles and responsibilities, and an implementation road map that will guide the Enterprise toward routinely providing the nation with comprehensive, skillful, reliable, sharp, and useful information about the uncertainty of hydrometeorological forecasts. The specific role of human forecasters in the day-to-day generation of probabilistic forecasts will depend on their ability to add value to raw and/or postprocessed ensemble model output. The NWS, for example, is providing gridded mosaics of sensible surface weather elements in its National Digital Forecast Database (NDFD).


Parks M.M.,COMET | Caliro S.,Italian National Institute of Geophysics and Volcanology | Chiodini G.,Italian National Institute of Geophysics and Volcanology | Pyle D.M.,COMET | And 6 more authors.
Earth and Planetary Science Letters | Year: 2013

Between January 2011 and April 2012, Santorini volcano (Greece) experienced a period of unrest characterised by the onset of detectable seismicity and caldera-wide uplift. This episode of inflation represented the first sizeable intrusion of magma beneath Santorini in the past 50 years. We employ a new approach using 222Rn-δ13C systematics to identify and quantify the source of diffuse degassing at Santorini during the period of renewed activity. Soil CO2 flux measurements were made across a network of sites on Nea Kameni between September 2010 and January 2012. Gas samples were collected in April and September 2011 for isotopic analysis of CO2 (δ13C), and radon detectors were deployed during September 2011 to measure (222Rn). Our results reveal a change in the pattern of degassing from the summit of the volcano (Nea Kameni) and suggest an increase in diffuse CO2 emissions between September 2010 and January 2012. High-CO2-flux soil gas samples have δ13C ~ 0‰. Using this value and other evidence from the literature we conclude that these CO2 emissions from Santorini were a mixture between CO2 sourced from magma, and CO2 released by the thermal or metamorphic breakdown of crustal limestone. We suggest that this mixing of magmatic and crustal carbonate sources may account more broadly for the typical range of δ13C values of CO2 (from ~ - 4‰ to ~ + 1‰) in diffuse volcanic and fumarole gas emissions around the Mediterranean, without the need to invoke unusual mantle source compositions. At Santorini a mixing model involving magmatic CO2 (with δ13C of -3 ± 2‰ and elevated (222Rn)/CO2 ratios ~105-106 Bqkg -1) and CO2 released from decarbonation of crustal limestone (with (222Rn)/CO2 ~ 30-300 Bqkg-1, and δ13C of +5‰) can account for the δ13C and (222Rn)/CO2 characteristics of the 'high flux' gas source. This model suggests ~60% of the carbon in the high flux deep CO2 end member is of magmatic origin. This combination of δ13C and (222Rn) measurements has potential to quantify magmatic and crustal contributions to the diffuse outgassing of CO2 in volcanic areas, especially those where breakdown of crustal limestone is likely to contribute significantly to the CO2 flux. © 2013 Elsevier B.V.


Petit V.W.,CNRS Laboratory of Communication Molecules and Adaptation of Microorganisms | Petit V.W.,CEA Fontenay-aux-roses | Rolland J.-L.,CNRS Host-Pathogen-Environment Interactions Laboratory | Blond A.,CNRS Laboratory of Communication Molecules and Adaptation of Microorganisms | And 8 more authors.
Biochimica et Biophysica Acta - General Subjects | Year: 2016

Background Hemocyanins are respiratory proteins with multiple functions. In diverse crustaceans hemocyanins can release histidine-rich antimicrobial peptides in response to microbial challenge. In penaeid shrimp, strictly antifungal peptides are released from the C-terminus of hemocyanins. Methods The three-dimensional structure of the antifungal peptide PvHCt from Litopenaeus vannamei was determined by NMR. Its mechanism of action against the shrimp pathogen Fusarium oxysporum was investigated using immunochemistry, fluorescence and transmission electron microscopy. Results PvHCt folded into an amphipathic α-helix in membrane-mimicking media and displayed a random conformation in aqueous environment. In contact with F. oxysporum, PvHCt bound massively to the surface of fungal hyphae without being imported into the cytoplasm. At minimal inhibitory concentrations, PvHCt made the fungal membrane permeable to SYTOX-green and fluorescent dextran beads of 4 kDa. Higher size beads could not enter the cytoplasm. Therefore, PvHCt likely creates local damages to the fungal membrane. While the fungal cell wall appeared preserved, gradual degeneration of the cytoplasm most often resulting in cell lysis was observed in fungal spores and hyphae. In the remaining fungal cells, PvHCt induced a protective response by the formation of daughter hyphae. Conclusion The massive accumulation of PvHCt at the surface of fungal hyphae and subsequent insertion into the plasma membrane disrupt its integrity as a permeability barrier, leading to disruption of internal homeostasis and fungal death. General significance The histidine-rich antimicrobial peptide PvHCt derived from shrimp hemocyanin is a strictly antifungal peptide, which adopts an amphipathic α-helical structure, and selectively binds to and permeabilizes fungal cells. © 2015 Elsevier B.V. All rights reserved.


PubMed | COMET, CNRS Laboratory of Communication Molecules and Adaptation of Microorganisms, CNRS Host-Pathogen-Environment Interactions Laboratory and University Pierre and Marie Curie
Type: Journal Article | Journal: Biochimica et biophysica acta | Year: 2016

Hemocyanins are respiratory proteins with multiple functions. In diverse crustaceans hemocyanins can release histidine-rich antimicrobial peptides in response to microbial challenge. In penaeid shrimp, strictly antifungal peptides are released from the C-terminus of hemocyanins.The three-dimensional structure of the antifungal peptide PvHCt from Litopenaeus vannamei was determined by NMR. Its mechanism of action against the shrimp pathogen Fusarium oxysporum was investigated using immunochemistry, fluorescence and transmission electron microscopy.PvHCt folded into an amphipathic -helix in membrane-mimicking media and displayed a random conformation in aqueous environment. In contact with F. oxysporum, PvHCt bound massively to the surface of fungal hyphae without being imported into the cytoplasm. At minimal inhibitory concentrations, PvHCt made the fungal membrane permeable to SYTOX-green and fluorescent dextran beads of 4 kDa. Higher size beads could not enter the cytoplasm. Therefore, PvHCt likely creates local damages to the fungal membrane. While the fungal cell wall appeared preserved, gradual degeneration of the cytoplasm most often resulting in cell lysis was observed in fungal spores and hyphae. In the remaining fungal cells, PvHCt induced a protective response by the formation of daughter hyphae.The massive accumulation of PvHCt at the surface of fungal hyphae and subsequent insertion into the plasma membrane disrupt its integrity as a permeability barrier, leading to disruption of internal homeostasis and fungal death.The histidine-rich antimicrobial peptide PvHCt derived from shrimp hemocyanin is a strictly antifungal peptide, which adopts an amphipathic -helical structure, and selectively binds to and permeabilizes fungal cells.

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