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The Arctic climate is projected to change during the coming century, with expected higher air temperatures and increased winter snowfall. These climatic changes might alter litter decomposition rates, which in turn could affect carbon (C) and nitrogen (N) cycling rates in tundra ecosystems. However, little is known of seasonal climate change effects on plant litter decomposition rates and N dynami

It remains unclear whether the event-related potential (ERP) correlates of episodic memory are modulated by the type of information retrieved. In two experiments, we recorded electrophysiological brain activity while participants discriminated between old and new items from three different stimulus categories (faces, objects, and words). In the first experiment, we used a randomized event-related

Using ultralow-power wake-up receivers (WRxs) can reduce idle listening energy cost in wireless sensor networks with low traffic intensity. This has led to many WRx analog front-end (AFE) designs presented in literature, with a large variety of trade-offs between the sensitivity, the data rate, and the power consumption. Energy consumed during wake-up in a network depends on many parameters and wi

Abstract This study relates soil organic matter (SOM) characteristics to initial soil incubation carbon release from upper permafrost samples in Yedoma region soils of northeastern Siberia, Russia. Carbon (C) and nitrogen (N) content, carbon to nitrogen ratios (C:N), δ13C and δ15N values show clear trends that correspond with SOM age and degree of decomposition. Incubation results indicate that ol

Recent research using repeat photography, long-term ecological monitoring and dendrochronology has documented shrub expansion in arctic, high-latitude and alpine tundra ecosystems. Here, we (1) synthesize these findings, (2) present a conceptual framework that identifies mechanisms and constraints on shrub increase, (3) explore causes, feedbacks and implications of the increased shrub cover in tun

Recently observed Arctic greening trends from normalized difference vegetation index (NDVI) data suggest that shrub growth is increasing in response to increasing summer temperature. An increase in shrub cover is expected to decrease summer albedo and thus positively feed back to climate warming. However, it is unknown how albedo and NDVI are affected by shrub cover and inter-annual variations in

The control of risks in engineering design is, for most conventional construction projects, achieved through the use of design codes. However, relying on design based on code-compliance can lead to situations where risks are overlooked or inadequately treated; a complementary approach is needed. In this paper, a holistic risk-informed approach for the treatment of accidental hazards during the con

We study System Optimum Dynamic Traffic Assignment (SO-DTA) for realistic traffic dynamics controlled by variable speed limits, ramp metering, and routing controls. We consider continuous-time cell-based Dynamic Network Loading models that include the Cell Transmission Model with FIFO rule at the diverge junctions as well as non-FIFO diverge rules. We consider SO-DTA formulations in which the tota

Now, more than ever, we are told that ‘authenticity’ is an added value that customers want. The objective of this study is to determine what authenticity relevant for design is and whether it can be used as a standardised procedure to improve product design. In this study, industrial designers have been interviewed about their views on authenticity. This paper is a combined result of a literature Now, more than ever, we are told that 'authenticity' is an added value that customers want. The objective of this study is to determine what kind of authenticity is relevant to design, and whether it can be used as a standardised procedure to improve product design. In this study industrial designers were interviewed about their views on authenticity. The paper represents the combined result of a

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

Thiosphaera pantotropha is capable of simultaneous heterotrophic nitrification and aerobic denitrification. Consequently, its nitrification potential could not be judged from nitrite accumulation, but was estimated from complete nitrogen balances. The maximum rate of nitrification obtained during these experiments was 93.9 nmol min−1 mg of protein−1. The nitrification rate could be reduced by the

The chapter monitors the different pillars of old age pension schemes and discusses coherence and coordination between primarily the public schemes and the occupational pension schemes with the example of the reformed Swedish model and takes into account both labour and tax related consequences. While the public pension scheme in Sweden was subject to significant reforms already 20 years ago, manyThis chapter monitors the different pillars of old-age pension schemes and discusses coherence and coordination, primarily between public schemes and occupational pension schemes, with the example of the reformed Swedish model. The chapter also takes into account both labour and tax-related consequences. While the public pension scheme in Sweden was already subject to significant reforms 20 years

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

An oxygen microsensor in combination with mathematical modeling was used to determine the behavior of immobilized Thiosphaera pantotropha. This organism can convert ammonia completely to nitrogen gas under aerobic conditions (coupled nitrification/denitrification) and denitrifies nitrate at highest rates under anaerobic conditions. Immobilization of T. pantotropha can result in aerobic and anaerob

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

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