Search results for "OAE"

Bioaerosols in the Earth system: Climate, health, and ecosystem interactions

2016

Abstract Aerosols of biological origin play a vital role in the Earth system, particularly in the interactions between atmosphere, biosphere, climate, and public health. Airborne bacteria, fungal spores, pollen, and other bioparticles are essential for the reproduction and spread of organisms across various ecosystems, and they can cause or enhance human, animal, and plant diseases. Moreover, they can serve as nuclei for cloud droplets, ice crystals, and precipitation, thus influencing the hydrological cycle and climate. The sources, abundance, composition, and effects of biological aerosols and the atmospheric microbiome are, however, not yet well characterized and constitute a large gap i…

2013

Abstract. Bioaerosols are relevant for public health and may play an important role in the climate system, but their atmospheric abundance, properties, and sources are not well understood. Here we show that the concentration of airborne biological particles in a North American forest ecosystem increases significantly during rain and that bioparticles are closely correlated with atmospheric ice nuclei (IN). The greatest increase of bioparticles and IN occurred in the size range of 2–6 μm, which is characteristic for bacterial aggregates and fungal spores. By DNA analysis we found high diversities of airborne bacteria and fungi, including groups containing human and plant pathogens (mildew, s…

Composition and diurnal variability of the natural Amazonian aerosol

2003

As part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA)-Cooperative LBA Airborne Regional Experiment (CLAIRE) 2001 campaign, separate day and nighttime aerosol samples were collected in July 2001 at a ground-based site in Amazonia, Brazil, in order to examine the composition and temporal variability of the natural “background” aerosol. A combination of analytical techniques was used to characterize the elemental and ionic composition of the aerosol. Major particle types larger than ∼0.5 μm were identified by electron and light microscopy. Both the coarse and fine aerosol were found to consist primarily of organic matter (∼70 and 80% by mass, respectively), with the coar…

Decontamination of Seawater in a Harbor: Case Study of Potential Bioterrorism Attack

2021

Bioterrorism attack to large harbors is likely, simply by the discharge of intentionally infected ship’s ballast water. Therefore, the ships must be equipped with the control probes of extensive microbial growth in the ballast water tanks to avoid such a scenario. In case of intentional discharge of ballast water containing Bacillus anthracis, a two-dimensional disinfection of the harbor’s seawater surface can be made using hydrophobic or surface-active disinfectant, by using humic acid with trimethylammonium groups, concentrating in the monomolecular layer on water–air interphase. It will prevent the formation and dispersion of the deadly bioaerosol to atmosphere after a bioterrorism attac…

Non-invasive monitoring of microbial contamination on graphic collections preserved in museums, libraries and archives

2016

Biological aerosol in indoor environments, such as museums, libraries and archives, can represent a hazard both for artworks, due to the presence of microorganisms, and for the health of operators and visitors, due to their potential infectious, allergenic or toxic effects. The detection of microbial colonization of air and surfaces, based on morphological and molecular analysis, is of fundamental importance for a correct preventive conservation and sustainable fruition. The results of the monitoring on both manufacts (prints, drawings), showing alterations potentially related to biological systems (foxing) and on furniture (metal cabinets, shelves, boxes) have been performed in the Central…

Évaluation des risques relatifs aux mesures de décontamination et de gestion des sous-produits animaux lors des cas de botulisme bovin et aviaire

2022

Le botulisme est une maladie neurologique humaine et animale, le plus souvent d’origine alimentaire, provoquée par l’action de neurotoxines bactériennes (toxines botuliques) produites par la bactérie Clostridium botulinum et qui se manifeste par une paralysie flasque pouvant aller jusqu’à la paralysie respiratoire et l’arrêt cardiaque. Neuf types toxiniques, répartis en une quarantaine de sous-types, sont actuellement connus.En France, le botulisme animal affecte essentiellement les oiseaux (sauvages et domestiques) et les bovins. Chez les volailles, on recense annuellement vingt à trente foyers, majoritairement dus aux types mosaïque C/D (élevages de poulets de chair et de dindes) suivi de…

Carbon-isotope record and palaeoenvironmental changes during the early Toarcian oceanic anoxic event in shallow-marine carbonates of the Adriatic Car…

2013

AbstractGeochemical (δ13C, δ18O and Mn) compositions of Lower Jurassic shallow-water carbonates cropping out in Croatia were analyzed to elucidate the impact of the early Toarcian oceanic anoxic event (T-OAE) on the Adriatic Carbonate Platform (AdCP). The bulk-rock carbon-isotope records through the studied sections (Velebit-A, Velebit-B and Gornje Jelenje) are characterized by two significant excursions: (i) an initial positive trend interrupted by a pronounced negative shift (c. 2.5‰) that is followed by (ii) an increasing trend of positive values (up to 4.5‰). A comparison with δ13C trends obtained from well-calibrated sections from other localities in Europe shows that the overall chara…

Indoor Air Quality including Respiratory Viruses

2021

The detection of SARS-CoV-2 in indoor environments is a cause of increasing concern. In this study, three sampling methodologies have been used in order to collect SARS-CoV-2 and 17 other respiratory viruses in indoor air, combined with a new analytical process to analyze respiratory viruses. Different areas of an ophthalmological hospital were investigated for the presence of these airborne viruses. Moreover, indoor air quality (IAQ) parameters (carbon dioxide, CO2; carbon monoxide, CO; nitrogen dioxide, NO2; volatile organic compounds, VOCs; formaldehyde, HCHO; and particulate matter, PM) have been examined to study the relationship between IAQ and airborne viruses. All indoor air and sur…

Lower Aptian climate and recording of the oceanic anoxic event 1a on the terrigenous shelf of the Paris Basin.

2021

Population response during an Oceanic Anoxic Event: The case of Posidonotis (Bivalvia) from the Lower Jurassic of the Neuquén Basin, Argentina

2019

Benthonic marine species show a wide range of biological reactions to seawater chemical changes through time, from subtle adjustments to extinction. The Early Toarcian Oceanic Anoxic Event (T-OAE) was recently recognized in the Neuquén Basin, Argentina, confirming its global scope. The event was identified chemostratigraphically on the basis of a relative increase in marine organic carbon and a characteristic negative carbon-isotope excursion (δ13Corg) in bulk rock and fossil wood in the upper Pliensbachian–lower Toarcian interval in the Arroyo Lapa section (Neuquén). Simultaneously with collection of lithological samples, a high-resolution biostratigraphical survey was carried out, and the…