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Fictitious Carbon, Fictitious Change? : Environmental Implications of the Commodification of Carbon

Governments increasingly rely on the use of market instruments to tackle climate change and help decarbonize a deeply fossil fuel-dependent economy. This dissertation examines this trend as one instance of the ‘commodification of carbon’, or the process through which emission reductions are made into commodities and then traded on the market. It engages the commodification framework and related th

Enhanced summer warming reduces fungal decomposer diversity and litter mass loss more strongly in dry than in wet tundra

Many Arctic regions are currently experiencing substantial summer and winter climate changes. Litter decomposition is a fundamental component of ecosystem carbon and nutrient cycles, with fungi being among the primary decomposers. To assess the impacts of seasonal climatic changes on litter fungal communities and their functioning, Betula glandulosa leaf litter was surface-incubated in two adjacen

The role of summer precipitation and summer temperature in establishment and growth of dwarf shrub Betula nana in northeast Siberian tundra

It is widely believed that deciduous tundra-shrub dominance is increasing in the pan-Arctic region, mainly due to rising temperature. We sampled dwarf birch (Betula nana L.) at a northeastern Siberian tundra site and used dendrochronological methods to explore the relationship between climatic variables and local shrub dominance. We found that establishment of shrub ramets was positively related t

Length Distributions of Nanowires Growing by Surface Diffusion

We present experimental data on the time and radius-dependent length distributions of Au-catalyzed InAs nanowires grown by metal organic vapor phase epitaxy. We show that these distributions are not as sharp as commonly believed. Rather, they appear to be much broader than Poissonian from the very beginning and spread quickly as the nanowires grow. We develop a model that attributes the observed b

Local Magnetic Suppression of Topological Surface States in Bi2Te3 Nanowires

Locally induced, magnetic order on the surface of a topological insulator nanowire could enable room-temperature topological quantum devices. Here we report on the realization of selective magnetic control over topological surface states on a single facet of a rectangular Bi2Te3 nanowire via a magnetic insulating Fe3O4 substrate. Low-temperature magnetotransport studies provide evidence for local

Neural correlates of mental context reinstatement supporting episodic memory retrieval

This study investigated if mental reinstatement of an encoding context during retrieval increases memory accessibility. Participants performed a cued-recall memory task where the overlap between encoding and retrieval context and the nature of context reinstatement (mental versus physical) were manipulated. Memory performance improved when the encoding-retrieval context overlapped in a comparable

Initial Stages of Tundra Shrub Litter Decomposition May Be Accelerated by Deeper Winter Snow But Slowed Down by Spring Warming

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

Electrophysiological correlates of episodic memory retrieval are material sensitive

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

Comparing Analog Front-Ends for Duty-Cycled Wake-Up Receivers in Wireless Sensor Networks

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

Thermokarst dynamics and soil organic matter characteristics controlling initial carbon release from permafrost soils in the Siberian Yedoma region : Limnological processes in permafrost environments

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

Shrub expansion in tundra ecosystems: dynamics, impacts and research priorities

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

The response of Arctic vegetation to the summer climate: relation between shrub cover, NDVI, surface albedo and temperature

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

Holistic approach for treatment of accidental hazards during conceptual design of bridge - A case study in Sweden

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

Convexity and Robustness of Dynamic Network Traffic Assignment for Control of Freeway Networks

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

Defining authenticity in product design

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