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The focus has recently been directed towards the engine out soot from Diesel engines. Running an engine in PPC (Partially Premixed Combustion) mode has a proven tendency of reducing these emissions significantly. In addition to combustion strategy, several studies have suggested that using alcohol fuels aid in reducing soot emissions to ultra-low levels. This study analyzes and compares the characThe focus has recently been directed towards the engine out soot from Diesel engines. Running an engine in PPC (Partially Premixed Combustion) mode has a proven tendency of reducing these emissions significantly. In addition to combustion strategy, several studies have suggested that using alcohol fuels aid in reducing soot emissions to ultra-low levels. This study analyzes and compares the charac

In this work, we generalize the recent sparse iterative covariance-based estimator (SPICE) by extending the problem formulation to allow for different norm constraints on the signal and noise parameters in the covariance model. The resulting extended SPICE algorithm offers the same benefits as the regular SPICE algorithm, including being hyper-parameter free, but the choice of norms allows further

High pressure reducing valve (HPRV) is widely used for pressure and temperature control of heated steams in power plant and other related process engineering. The structures of throttling components inside HPRVs have important effects on the control performances. In this paper, a parametric study of throttling components in a multi-stage high pressure reducing valve (MSHPRV) is carried out, includ

Biografisk artikel om språkvetaren m m Hjalmar Edgren (1840-1903) med tonvikt på hans period som docent vid Lunds universitet 1880-1885 samt de kontakter med andra lundaakademiker han därvid skaffade sig.

Semiconductor nanowires are often regarded as having potential to be building blocks for novel applications. Their geometry allows defect-free combinations of materials that have a high degree of lattice mismatch. III-V semiconductor nanowires can also be grown in the wurtzite crystal phase, which is not stable in bulk material or thin films. The atomic arrangement differs between wurtzite and zin

Resultaten i denna avhandling ökar vår kunskap om hur evolutionen av feromondetektering hos fjärilar gått till.Luktsinnet är viktigt för de flesta djur, inklusive människor, hundar, insekter och många andra. Hos insekter, särskilt nattfjärilar och flugor, används luktsinnet för att hitta parningspartners, föda, äggläggningsställen och att undkomma fiender.Feromoner är kemikalier som produceras ochIn moths, females produce sex pheromone compounds to attract males over a long distance for mating. The antennae of moths and many other insects have specialized odorant receptors (ORs), called pheromone receptors (PRs), to sense the pheromone compounds and they group in a monophyletic clade (PR clade).In this thesis, I investigated and compared various components of the olfactory system in differ

Small remnants of non-arable habitat within the farmland mosaic are considered important for the conservation of farmland biodiversity, but their contribution to landscape-scale species richness is poorly understood. In the present study, we examined the relative contributions of different habitat types to the landscape-scale species richness of vascular plants within farmland of varying landscape

Ribs are often employed in internal cooling passages of turbine blades to augment heat transfer with cooling air flowing through the internal ribbed passages. The present work concentrates on truncated ribs to improve thermal performances with continuous ribs in a high aspect ratio channel. With various truncation types and arrangements of truncated ribs, the optimized thermal performance of ribbe

One challenge in the development of laser wakefield accelerators is to demonstrate sufficient control and reproducibility of the parameters of the generated bunches of accelerated electrons. Here we report on a numerical study, where we demonstrate that trapping using density down-ramps allows for tuning of several electron bunch parameters by varying the properties of the density down-ramp. We sh

Marine seismic data are distorted by ghosts as waves propagating upward reflect downward from the sea surface. Ghosts appear on the source side and the receiver side. However, whereas the receiver-side ghost problem has been studied in detail, and many different solutions have been proposed and implemented commercially, the source-side ghost problem has remained largely unsolved with few satisfact

I Lunds universitets strategiska plan för 2012-2016 framhålls att man vill ”vidareutveckla det akademiska lärarskapet”. All utbildning vid lärosätet ska hålla högsta kvalitet och man ska erbjuda attraktiva och akademiskt framstående lärandemiljöer. Detta åstadkoms bland annat genom att universitetets lärare kan ”arbeta med ett forskande förhållningssätt, både i förhållande till studenternas lärand

Metal nanoclusters, supported on inert substrates, exhibiting well-defined shapes and sizes in a broad range of temperatures are a major object of desire in nanotechnology. Here, a technique is presented that improves the thermal stability of monodisperse and crystalline transition metal nanoclusters grown in a regular array on metal-supported graphene. To stabilize the clusters after growth under

We explored the role of the Krebs cycle enzyme fumarate hydratase (FH) in glucose-stimulated insulin secretion (GSIS). Mice lacking Fh1 in pancreatic β cells (Fh1βKO mice) appear normal for 6–8 weeks but then develop progressive glucose intolerance and diabetes. Glucose tolerance is rescued by expression of mitochondrial or cytosolic FH but not by deletion of Hif1α or Nrf2. Progressive hyperglycem

Although a causative role of α-synuclein (α-syn) is well established in Parkinson’s disease pathogenesis, available animal models of synucleinopathy do not replicate the full range of cellular and behavioral changes characteristic of the human disease. This study was designed to generate a more faithful model of Parkinson’s disease by injecting human α-syn fibril seeds into the rat substantia nigr

Helianthemum oelandicum var. canescens (Hartm.) Fr. is an endemic taxon with a restricted distribution (less than 10 km2) in the southernmost part of the Baltic island of Öland, SE, Sweden. The taxon varies with respect to stellate hairs. Most plants can be classified into two morphs, the stellated morph (with a dense carpet of stellate hairs on the abaxial surface of the leaves) and the bristled

The purpose of this article is to analyze how university teachers’ professionalism shapes the coordination processes in higher education institutions (HEIs). By developing an innovative framework, which combines governance theories and theories about professionalization, we found that university teachers’ roles in coordination with governance actors in HEIs follow two different logics: to comply w

Subclinical vitamin K deficits refer to carboxylation defects of different types of vitamin K-dependent hepatic and extrahepatic so-called Gla proteins without prolongation of the prothrombin time. This condition has been reported in different clinical situations due to insufficient supply or malabsorption of vitamin K as well as drug interactions. This review discusses the effects of different vi

This study demonstrates the effect of column selectivity and density of supercritical carbon dioxide (SC-CO2) on the separation of monochloropropanediol (MCPD) esters, known as food toxicants, using SC-CO2 without addition of cosolvent in ultrahigh performance supercritical fluid chromatography-mass spectrometry (UHPSFC-MS). This study shows that over 20 2-monochloropropanediol (2-MCPD) and 3-mono

This work analyzes the effects on support recovery for different choices of the hyper- or regularization parameter in LASSO-like sparse and group-sparse regression problems. The hyperparameter implicitly selects the model order of the solution, and is typically set using cross-validation (CV). This may be computationally prohibitive for large-scale problems, and also often overestimates the model