The Experts below are selected from a list of 420 Experts worldwide ranked by ideXlab platform

Marius Dybwad - One of the best experts on this subject based on the ideXlab platform.

  • temporal variability of the bioaerosol background at a subway station concentration level size distribution and diversity of Airborne bacteria
    Applied and Environmental Microbiology, 2014
    Co-Authors: Marius Dybwad, Gunnar Skogan, Janet Martha Blatny
    Abstract:

    Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of Airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the Airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 10 3 CFU m 3 and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The Airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne Bacterium-containing particles were distributed between different sizes for particles of>1.1m, although50% were between 1.1 and 3.3 m. Anthropogenic activities (mainly passengers) were demonstrated as major sources of Airborne bacteria and predominantly contributed 1.1- to 3.3-m Bacterium-containing particles. Ourfindings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents.

Janet Martha Blatny - One of the best experts on this subject based on the ideXlab platform.

  • temporal variability of the bioaerosol background at a subway station concentration level size distribution and diversity of Airborne bacteria
    Applied and Environmental Microbiology, 2014
    Co-Authors: Marius Dybwad, Gunnar Skogan, Janet Martha Blatny
    Abstract:

    Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of Airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the Airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 10 3 CFU m 3 and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The Airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne Bacterium-containing particles were distributed between different sizes for particles of>1.1m, although50% were between 1.1 and 3.3 m. Anthropogenic activities (mainly passengers) were demonstrated as major sources of Airborne bacteria and predominantly contributed 1.1- to 3.3-m Bacterium-containing particles. Ourfindings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents.

John D. Macmicking - One of the best experts on this subject based on the ideXlab platform.

  • Cell-Autonomous Effector Mechanisms against MycoBacterium
    2016
    Co-Authors: John D. Macmicking
    Abstract:

    Few pathogens run the gauntlet of sterilizing immunity like MycoBacterium tuberculosis (Mtb). This organism infects mononuclear phagocytes and is also ingested by neutrophils, both ofwhichpossess an arsenal of cell-intrinsic effectormechanisms capable of eliminating it. Here Mtb encounters acid, oxidants, nitrosylating agents, and redox congeners, often exuberantly delivered under low oxygen tension. Further pressure is applied by withholding divalent Fe2þ, Mn2þ, Cu2þ, and Zn2þ, aswell as bymetabolic privation in the form of carbon needed for anaplerosis and aromatic amino acids for growth. Finally, host E3 ligases ubiq-uinate, cationic peptides disrupt, and lysosomal enzymes digestMtb as part of the autopha-gic response to this particular pathogen. It is a testament to the evolutionary fitness ofMtb that sterilization is rarely complete, although sufficient to ensure most people infected with this Airborne Bacterium remain disease-free. Cells constitute the basic unit in biology.They safeguard and transmit genetic infor-mation, exchange gases, assimilate nutrients, and compartmentalize their enzymaticmachin-ery to concentrate activities that share a com

Gunnar Skogan - One of the best experts on this subject based on the ideXlab platform.

  • temporal variability of the bioaerosol background at a subway station concentration level size distribution and diversity of Airborne bacteria
    Applied and Environmental Microbiology, 2014
    Co-Authors: Marius Dybwad, Gunnar Skogan, Janet Martha Blatny
    Abstract:

    Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of Airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the Airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 10 3 CFU m 3 and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The Airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne Bacterium-containing particles were distributed between different sizes for particles of>1.1m, although50% were between 1.1 and 3.3 m. Anthropogenic activities (mainly passengers) were demonstrated as major sources of Airborne bacteria and predominantly contributed 1.1- to 3.3-m Bacterium-containing particles. Ourfindings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents.

Dale L Handlin - One of the best experts on this subject based on the ideXlab platform.

  • antimicrobial behavior of semifluorinated quaternized triblock copolymers against Airborne and marine microorganisms
    ACS Applied Materials & Interfaces, 2010
    Co-Authors: Daewon Park, John A Finlay, Rebekah J Ward, Craig J Weinman, Sitaraman Krishnan, Marvin Y Paik, Karen E Sohn, Maureen E Callow, James A Callow, Dale L Handlin
    Abstract:

    Semifluorinated-quaternized triblock copolymers (SQTCs) were synthesized by chemical modification of polystyrene-block-poly(ethylene-ran-butylene)-block-polyisoprene ABC triblock copolymers. Surface characterization of the polymers was performed by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) analysis. The surface of the SQTC showed very high antibacterial activity against the Airborne Bacterium Staphylococcus aureus with >99 % inhibition of growth. In contrast in marine fouling assays, zoospores of the green alga Ulva settled on the SQTC, which can be attributed to the positively charged surface. The adhesion strength of sporelings (young plants) of Ulva and Navicula diatoms (a unicellular alga) was high. The SQTC did not show marked algicidal activity.