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Parameters Influencing Soot Oxidation Rates in an Optical Diesel Engine

Soot emissions from diesel engines are the net result of two competing processes: soot formation and soot oxidation. Previous studies have shown poor correlation between soot formation rates and the soot emissions. This article presents a systematic study of a number of parameters affecting soot oxidation rate and how it correlates with the soot emissions. An optical heavy-duty engine is used in c

Comparison of Laser-Extinction and Natural Luminosity Measurements for Soot Probing in Diesel Optical Engines

Soot emissions from diesel internal combustion engines are strictly regulated nowadays. Laser extinction measurement (LEM) and natural luminosity (NL) of sooty flames are commonly applied to study soot. LEM measures soot along the laser beam path and it can probe soot regardless of temperature. NL integrates the whole field of view and relies on soot temperature. In this work, a comparison of simu

A Study of In-Cylinder Soot Oxidation by Laser Extinction Measurements During an EGR-Sweep in an Optical Diesel Engine

Two competing in-cylinder processes, soot formation and soot oxidation, govern soot emissions from diesel engines. Previous studies have shown a lack of correlation between the soot formation rate and soot emissions. The current experiment focuses on the correlation between soot oxidation rates and soot emissions. Laser extinction is measured using a red (690nm) laser beam, which is sent verticall

Investigation of Late-Cycle Soot Oxidation Using Laser Extinction and In-Cylinder Gas Sampling at Varying Inlet Oxygen Concentrations in Diesel Engines

This study focuses on the relative importance of O2 and OH as oxidizers of soot during the late cycle in diesel engines, where the soot oxidation is characterized in an optically accessible engine using laser extinction measurements. These are combined with in cylinder gas sampling data from a single cylinder engine fitted with a fast gas sampling valve. Both measurements confirm that the in-cylin

Quality Registries in Sweden, Healthcare Improvements and Elderly Persons with Cognitive Impairments

Policy-makers, the medical industry and researchers are demonstrating a keen interest in the potential of large registries of patient data, both nationally and internationally. The registries offer promising ways to measure and develop operational quality within health and medical care services. As a result of certain favourable patient data regula- tions and government funding, the development of

Neurons against Noise : Neural adaptations for dim light vision in hawkmoths

Alla djur uppfattar världen med sina sinnen, vilka ger information till beslut och rörelser. Tyvärr har sinnena begränsningar och när de upphör att ge pålitlig information kommer djurets överlevnad att hotas. Synsinnet till exempel utmanas dagligen, eftersom dess signalstyrka minskar när mörkret faller och ökar igen när solen går upp. I denna avhandling undersökte jag synsystemets anpassningar hosAll animals perceive the world through their senses, which form the basis for their decisions and motor actions. However, when these all-important senses reach their limit and cease to provide reliable information, the animal’s survival is threatened. Among the senses, vision is brought to its limits on a daily basis, because its signal strength is diminished as night falls, and increases again as

N-acetylation of arylalkylmines (serotonin and tryptamine) in the crayfish brain.

1. The presence of N-acetyltransferase in the crayfish brain (Pacifastacus leniusculus) was investigated. The arylalkylamines tryptamine and 14C-serotonin, are acetylated by crayfish brain homogenates with the acetyl donors 3H-acetyl coenzyme A and N, S-diacetylcysteamine, respectively.2. Resolution of serotonin metabolites by thin layer chromatography (chloroform/methanol/glacial acetic acid, 93

Identification of L-3,4-dihydroxyphenylalanine in the brain of the crayfish Pacifastacus leniusculus (Dana) and in tentacles of the sea anemone Metridium senile (L) by use of gas chromatography-mass spectrometry.

1. The amino acid l-3,4-dihydroxyphenylalanine (l-DOPA) was extracted from tentacles of the sea anemone Metridium senile and from brains of the crayfish Pacifastacus leniuscuius.2. The identity of l-DOPA was ascertained by gas chromatography-mass spectrometry as the heptafluorobutyryl iso-butyl ester derivative. Dopa is identified with GC-MS for the first time and the derivatization is a novel mod

Gland cells in the tentacles of the jellyfish Cyanea lamarcki reactive with an antibody against 5-hydroxytryptamine.

A light- and electron-microscopic immunocytochemical study on the localization of 5-hydroxytryptamine in Cyanea lamarcki revealed a reaction product in the epidermal gland cells surrounding the nematocyst clusters. The closely related scyphozoan medusa Cyanea capillata lacked a reaction product in the similar mucus-producing gland cells. Earlier conflicting views on the presence and localization o

Single modified cilia displayed by cells of human internal stratifed epithelia (oral cavity, vagina)

Serial sections of human vaginal and keratinized oral-gingival epithelia were investigated for ciliary structures. Most melanocytes of the gingival epithelium lacked cilia, whereas almost all basal keratinocytes of the deeper portion of the epithelial ridges possessed one cilium each. In the suprabasal layers of the ridges only a few keratinocytes exhibited a single cilium. In the basal layer, at

Presence of 3 4-dihydroxyphenylalanine and 3,4,5-trihydroxyphenylalanine in a coelenterate nervous system: possible tyrosinase-mediated accumulation.

3,4-dihydroxyphenylalanine (DOPA), 3,4,5-trihydroxyphenylalanine (5-OH-DOPA), 5-S-cysteinylDOPA (5-SC.D) and 2-S-cysteinylDOPA (2-SC.D) in the tentacles of the sea anemone, Metridium senile, were studied by the combined use of differential centrifugation of tissue homogenates, ultracentrifugation on sucrose density gradients, HPLC and electron microscopy. DOPA, 5-OH-DOPA and o-diphenol:O2 oxidored

The Role of Public Transport in Society—A Case Study of General Policy Documents in Sweden

Abstract: The aim of this paper is to study how local governments in Sweden view the role of public transport in society, and to investigate how public transport is used in a strategic capacity. By studying general policy documents, the ambition is to gain a wider understanding of the role of public transport based on the societal context it is situated in. Documents from 15 regions and 27 municipThe aim of this paper is to study how local governments in Sweden view the role of public transport in society, and to investigate how public transport is used in a strategic capacity. By studying general policy documents, the ambition is to gain a wider understanding of the role of public transport based on the societal context it is situated in. Documents from 15 regions and 27 municipalities ha

Competition between managed honeybees and wild bumblebees depends on landscape context

Honeybees might outcompete wild bees by depleting common resources, possibly more so in simplified landscapes where flower-rich habitats have been lost. We tested this by experimentally adding honeybee hives to nine sites while ensuring that ten additional sites were free from hives. The landscape surrounding each geographically separated site either held low (homogeneous landscape) or high (heter

Reconstructing Recent Work on Macrosocial Stress as a Research Program

We reconstruct recent work on macrosocial stress (Chou, Parmar, & Galinsky, 2016) as if it were an instance of a research strategy that tests point-alternative hypotheses within a full-fledged research program. Because this strategy is free of various deficits that beset dominant strategies (e.g., meta-analysis, Bayes factor analysis), our article demonstrates one way in which the confidence c

Association between uterine artery Doppler blood flow changes and arterial wall elasticity in pregnant women

Introduction: Uterine artery (UtA) Doppler velocimetry changes and increased arterial stiffness are associated with preeclampsia. We aimed to investigate the relation between UtA velocimetry changes and arterial stiffness in pregnant women. Methods: Doppler velocimetry and photoplethysmographic digital pulse wave analysis (DPA) were performed in 173 pregnant women in the second or the third trimes

High-frequency InGaAs tri-gate MOSFETs with fmax of 400 GHz

Extremely scaled down tri-gate RF metal-oxide-semiconductor field-effect transistors (MOSFETs) utilising lateral nanowires as the channel, with gate length and nanowire width both of 20 nm are reported. These devices exhibit simultaneous extrapolated ft and fmax of 275 and 400 GHz at VDS = 0.5 V, which is the largest combined ft and fmax, as well as the largest fmax reported for all III-V MOSFETs.

Big Science Transformed : Science, Politics and Organization in Europe and the United States

This book analyses the emergence of a transformed Big Science in Europe and the United States, using both historical and sociological perspectives. It shows how technology-intensive natural sciences grew to a prominent position in Western societies during the post-World War II era, and how their development cohered with both technological and social developments. At the helm of post-war science ar

Hypoparathyroidism after total thyroidectomy in patients with previous gastric bypass

Purpose: Case reports suggest that patients with previous gastric bypass have an increased risk of severe hypocalcemia after total thyroidectomy, but there are no population-based studies. The prevalence of gastric bypass before thyroidectomy and the risk of hypocalcemia after thyroidectomy in patients with previous gastric bypass were investigated. Methods: By cross-linking The Scandinavian Quali