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The use of a metabolically structured model in the study of growth, nitrification, and denitrification by Thiosphaera pantotropha

Thiosphaera pantotropha is capable of aerobic heterotropic nitrification and both aerobic and anaerobic denitrification. These phenomena have been studied in acetate-limited aerobic and anaerobic continous cultures supplied with ammonia and nitrate. The internal reaction rates were defined, based on biochemical knowledge. The observable external conversion rates are related through a linear equati

Heterotrophic nitrification and aerobic denitrification in Alcaligenes faecalis strain TUD

Heterotrophic nitrification and aerobic and anaerobic denitrification byAlcaligenes faecalis strain TUD were studied in continuous cultures under various environmental conditions. Both nitrification and denitrification activities increased with the dilution rate. At dissolved oxygen concentrations above 46% air saturation, hydroxylamine, nitrite and nitrate accumulated, indicating that both the ni

Shrub expansion may reduce summer permafrost thaw in Siberian tundra

Climate change is expected to cause extensive vegetation changes in the Arctic: deciduous shrubs are already expanding, in response to climate warming. The results from transect studies suggest that increasing shrub cover will impact significantly on the surface energy balance. However, little is known about the direct effects of shrub cover on permafrost thaw during summer. We experimentally quan

Where identity meets information : teacher trainees' performance of identity positions and information activities

Introduction. This paper reports findings from an on-going analysis of how pre-school teacher trainees position their identities, as learners and future pre-school teachers, as information activities are performed in a Facebook Group and on a blog. Method. The analysis is based on results from an ethnographic study at a pre-school teacher-training programme at a Swedish university. Participant obs

Competition between heterotrophic and autotrophic nitrifiers for ammonia in chemostat cultures

Mixed cultures of a heterotrophic nitrifier/aerobic denitrifier, Thiosphaera pantotropha, and an autotrophic nitrifier, Nitrosomonas europaea, were grown in chemostats under dual ammonia-and acetate limitation. Because of simultaneous nitrification and denitrification by T. pantotropha, the activity of the cultures was evaluated from nitrogen balances as complete as possible. Under most conditions

Where and how do you buy medicines? : Report

In order to understand where and how the Swedish public access their medicines, especially prescribed medicines, an online survey was conducted as a pilot study during April and May 2016. Among a collection of 155 answers, the data shows that, although a majority of the respondents feel hesitated and negative towards shopping prescribed medicines online, a tendency is demonstrated that people woul

Low Cost Remote Antenna Units in CMOS for Fiber-fed Distributed MIMO Systems

Massive multiple input multiple output (MIMO) is a revolutionary communication technique, where large numbers of antennas are employed at the base stations to increase the spectral efficiency, reliability and data rate of the system. Moreover, in multi-user MIMO (MU-MIMO) multiple users can be served by the base stations on the same time-frequency resource. Distributed antenna system (DAS) is a fo

Inhibition of denitrification and oxygen utilization by Thiosphaera pantotropha

Mass spectrometry confirmed that the entire denitrification system of Thiosphaera pantotropha is present under aerobic conditions. Acetate-dependent oxygen uptake is totally inhibited by 0.3mM cyanide. Nitrate reduction by cells grown with and without nitrate was inhibited by 10 and 15mM azide, respectively. The nitrous oxide reductase was totally inhibited by 1% acetylene or 0.125mM cyanide. This

3-Phosphoinositide-dependent kinase 1 potentiates upstream lesions on the phosphatidylinositol 3-kinase pathway in breast carcinoma

Lesions of ERBB2, PTEN, and PIK3CA activate the phosphatidylinositol 3-kinase (PI3K) pathway during cancer development by increasing levels of phosphatidylinositol-3,4,5-triphosphate (PIP(3)). 3-Phosphoinositide-dependent kinase 1 (PDK1) is the first node of the PI3K signal output and is required for activation of AKT. PIP(3) recruits PDK1 and AKT to the cell membrane through interactions with the

A typology of fisheries management tools : Using experience to catalyse greater success

Fisheries provide nutrition and livelihoods for coastal populations, but many fisheries are fully or over-exploited and we lack an approach for analysing which factors affect management tool performance. We conducted a literature review of 390 studies to assess how fisheries characteristics affected management tool performance across both small-scale and large-scale fisheries. We defined success a

The variation of productivity and its allocation along a tropical elevation gradient : A whole carbon budget perspective

Summary: Why do forest productivity and biomass decline with elevation? To address this question, research to date generally has focused on correlative approaches describing changes in woody growth and biomass with elevation. We present a novel, mechanistic approach to this question by quantifying the autotrophic carbon budget in 16 forest plots along a 3300 m elevation transect in Peru. Low growt