Ammonia-oxidizing archaea (AOA) are among the most abundant microorganisms and key players in the global nitrogen and carbon cycles. They share a common energy metabolism but represent a heterogeneous group with respect to their environmental distribution and adaptions, growth requirements, and genome contents. We report here the genome and proteome of Nitrososphaera viennensis EN76, the type s...

The contribution of ammonia-oxidizing bacteria and archaea (AOB and AOA, respectively) to the net oxidation of ammonia varies greatly between terrestrial environments. To better understand, predict and possibly manage terrestrial nitrogen turnover, we need to develop a conceptual understanding of ammonia oxidation as a function of environmental conditions including the ecophysiology of associat...

Ammonia-oxidizing archaea (AOA) are an important component of the planktonic community in aquatic habitats, linking nitrogen and carbon cycles through nitrification and carbon fixation. Therefore, measurements of these processes in culture-based experiments can provide insights into their contributions to energy conservation and biomass production by specific AOA. In this study, by enriching AO...

In their natural habitats, microorganisms are often exposed to periods of starvation if their substrates for energy generation or other nutrients are limiting. Many microorganisms have developed strategies to adapt to fluctuating nutrients and long-term starvation. In the environment, ammonia oxidizers have to compete with many different organisms for ammonium and are often exposed to long peri...

To exploit the capacity and performance gains associated with the use of antenna arrays, wireless communication systems require proper understanding of the spatial characteristics of the channel. Scattering models provide both Angle of Arrival (AoA) and Time of Arrival (ToA) statistics of the channel. In this paper, we investigate geometrically based single bounce model that assumes that multip...

When an activity-on-arc (AoA) project network is to be constructed, one typically seeks to minimize the number of dummy arcs. Recent investigations have shown, however, that the computational effort of many network-oriented project management techniques depends strongly on the so-called complexity index ( C l ) of a network. We show other justifications for minimizing the Cl rather than the num...

Ammonia oxidation is an important process for decreasing ammonia concentrations in wastewater-impacted rivers. Ammonia-oxidizing bacteria (AOB) and archaea (AOA) are re sponsible for ammonia oxidation, which is the first step of the nitrification process. Nitrification and urea hydrolysis were monitored in sediment and water column samples in the Grand River (Ontario), and nitrification inhibit...

Program directors of American Osteopathic Association (AOA)-approved primary care graduate training programs were surveyed concerning the relative importance of 12 academic and 10 nonacademic performance-based variables related to trainee selection. Programs holding both AOA and Accreditation Council for Graduate Medical Education approval were also compared to programs holding only AOA approva...

OBJECTIVES To determine the accuracy of calcium-containing rings measurements imaged by three-dimensional echocardiography (3DE), multi-slice CT (MSCT) and cardiac magnetic resonance (CMR) under ideal conditions against the true ring dimensions. To compare the accuracy of aortic annulus (AoA) measurements in ex vivo human hearts using 3DE, MSCT and CMR. To determine the accuracy of AoA measurem...

The beneficial influence of many foodstuffs and beverages including fruits, vegetables, tea, red wine, coffee, and cacao on human health has been recently recognized to originate from the chain-breaking antioxidant activity (AOA) of natural polyphenols, a significant constituent of the above products. For this reason, the dietary value of such products is determined to a large extent by their A...