Aviaja Anna Hansen

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The viable and non-viable fractions of the bacterial community in a 2347-year-old permafrost soil from Spitsbergen were subjected to a comprehensive investigation using culture-independent and culture-dependent methods. LIVE/DEAD BacLight staining revealed that 26% of the total number of bacterial cells were viable. Quantitatively, aerobic microcolonies,(More)
The microbial populations in 25 full-scale activated sludge wastewater treatment plants with enhanced biological phosphorus removal (EBPR plants) have been intensively studied over several years. Most of the important bacterial groups involved in nitrification, denitrification, biological P removal, fermentation, and hydrolysis have been identified and(More)
The diversity of the putative polyphosphate-accumulating genus Tetrasphaera in wastewater treatment systems with enhanced biological phosphorus removal (EBPR) was investigated using the full-cycle rRNA approach combined with microautoradiography and histochemical staining. 16S rRNA actinobacterial gene sequences were retrieved from different full-scale EBPR(More)
The Microbial Database for Activated Sludge (MiDAS) field guide is a freely available online resource linking the identity of abundant and process critical microorganisms in activated sludge wastewater treatment systems to available data related to their functional importance. Phenotypic properties of some of these genera are described, but most are known(More)
Enhanced biological phosphorus removal (EBPR) is one of the most advanced and complicated wastewater treatment processes applied today, and it is becoming increasingly popular worldwide as a sustainable way to remove and potentially reuse P. It is carried out by complex microbial communities consisting primarily of uncultured microorganisms. The EBPR(More)
Modern intensive husbandry practices can create poor indoor air quality, with high levels of airborne dust, endotoxins, ammonia, and microorganisms. Air in a sow breeding barn was investigated to determine the biomass composition of bioaerosols using molecular methods supplemented with microscopic and cultivation-dependent approaches. A total of 2.7 ± 0.7 ×(More)
Indigenous bacteria and biomolecules (DNA and proteins) in a freeze-dried and homogenized Arctic permafrost were exposed to simulated martian conditions that correspond to about 80 days on the surface of Mars with respect to the accumulated UV dose. The simulation conditions included UV radiation, freeze-thaw cycles, the atmospheric gas composition, and(More)
We describe the design, construction, and pilot operation of a Mars simulation facility comprised of a cryogenic environmental chamber, an atmospheric gas analyzer, and a xenon/mercury discharge source for UV generation. The Mars Environmental Simulation Chamber (MESCH) consists of a double-walled cylindrical chamber. The double wall provides a cooling(More)
Membrane fouling presents the greatest challenge to the application of membrane bioreactor (MBR) technology. Formation of biofilms on the membrane surface is the suggested cause, yet little is known of the composition or dynamics of the microbial community responsible. To gain an insight into this important question, we applied 16S rRNA gene amplicon(More)