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Direct injection (DI) natural gas engines are modern engine concepts providing clean combustion and high fuel efficiency. Even at high injection pressures, such engines operate at heterogeneous/stratified fuel/air mixture conditions due to the relatively short mixing time of the fuel jet. The sub-optimal fuel-air mixture results in emissions of unburnt hydrocarbon (UHC). In particular, one of the

Changing Landscapes and Persistent Places is a study of the cultural landscape on the Bjäre peninsula in northwest Skåne. The many Bronze Age remains that give the landscape its distinctive character are the starting point for an attempt to increase our understanding of the historical depth of today’s landscape. The two perspectives of “landscape” and “places” carry the discussion forward, almost

In the first part of this thesis discrete time hedging is considered. In paper A an adaptive hedging scheme where the hedge portfolio is re-balanced when the hedge ratios differ by some amount, here denoted eta, is investigated. An expression of the normalized expected mean squared hedging error as eta tends to zero is derived. The result is compared to an earlier result on discrete time hedging o

It has previously been shown by the authors that the pre-chamber ignition technique operating with fuel-rich pre-chamber combustion strategy is a very effective means of extending the lean limit of combustion with excess air in heavy duty natural gas engines in order to improve indicated efficiency and reduce emissions. This article presents a study of the influence of pre-chamber volume and nozzl

Background: Intolerance of uncertainly (IU), cognitive avoidance (CA) and positive beliefs about worry (PB) independently predict worry frequency in older adolescents and adults, and when targeted together in treatment produce significant reductions in both worry and anxiety in this age range. The present study addresses a gap in the literature by testing whether a cognitive model of excessive wor

In dynamic flexgrid optical networks, the usage of capacity may not be optimal due to the permanent process of setting up and tearing down connections, which, if not controlled, leads to spectrum fragmentation and, as a result, to increase of connection blocking. On top of this, a restoration mechanism that is launched in reaction to a link failure (cable cut) restores the affected lightpaths. Eve

The outcomes of the Fourth Session of the Global Platform for Disaster Risk Reduction show that making cities and rural areas safe from disasters and climate change impacts and enhancing citizens' resilience is everybody's business and part of the larger sustainability challenge. Under the theme Resilient People, Resilient Planet', the session took place on 19-23 May 2013 in Geneva, Switzerland. T

Baker's yeast (Saccharomyces cerevisiae) has been genetically engineered to ferment the pentose sugar xylose present in lignocellulose biomass. One of the reactions controlling the rate of xylose utilization is catalyzed by xylose reductase (XR). In particular, the cofactor specificity of XR is not optimized with respect to the downstream pathway, and the reaction rate is insufficient for high xyl

The key step in the reaction mechanism of multicopper oxidases (MCOs)-the cleavage of the O-O bond in O-2-has been investigated using combined quantum mechanical and molecular mechanical (QM/MM) methods. This process represents a reaction pathway from the peroxy intermediate after it accepts one electron from the nearby type-1 Cu site to the experimentally-observed native intermediate, which is th

The oxidation of biogenic volatile organic compounds (BVOCs) gives a range of products, from semi-volatile to extremely low-volatility compounds. To treat the interaction of these secondary organic vapours with the particle phase, global aerosol microphysics models generally use either a thermodynamic partitioning approach (assuming instant equilibrium between semi-volatile oxidation products and

The prototypical antimicrobial peptide, melittin, is well-known for its ability to induce pores in zwitterionic model lipid membranes. However, the mechanism by which melittin accomplishes this is not fully understood. We have conducted all-atom and coarse-grained molecular dynamics simulations which suggest that melittin employs a highly cooperative mechanism for the induction of both small and l

Nitrous oxide, carbon dioxide and methane are greenhouse gases (GHG) emitted from wastewater treatment that contribute to its carbon footprint. As a result of the increasing awareness of GHG emissions from wastewater treatment plants (WWTPs), new modelling, design, and operational tools have been developed to address and reduce GHG emissions at the plant-wide scale and beyond. This paper reviews t

The objective of this work is to establish under which conditions short RNA molecules (similar to miRNA) associate with zwitterionic phospholipids and how this differs from the association with cationic surfactants. We study how the base pairing (i.e., single stranded versus double stranded nucleic acids) and the length of the nucleic acid and the charge of the lipid/surfactant monolayer affect th

Negative pressure wound therapy (NPWT) has become widely adopted over the last 15 years and over 1000 peer reviewed publications are available describing its use. Despite this, there remains uncertainty regarding several aspects of usage. In order to respond to this gap a global expert panel was convened to develop evidence-based recommendations describing the use of NPWT. In this paper the result

High-energy proton- and deuteron-nucleus collisions provide an excellent tool for studying a wide array of physics effects, including modifications of parton distribution functions in nuclei, gluon saturation, and color neutralization and hadronization in a nuclear environment, among others. All of these effects are expected to have a significant dependence on the size of the nuclear target and th

Readouts that define the physiological distributions of drugs in tissues are an unmet challenge and at best imprecise, but are needed in order to understand both the pharmacokinetic and pharmacodynamic properties associated with efficacy. Here we demonstrate that it is feasible to follow the in vivo transport of unlabeled drugs within specific organ and tissue compartments on a platform that appli