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We analyzed the evolution of the radial profiles and the azimuthal variations of the stellar metallicities from the VINTERGATAN simulation of a Milky Way-like galaxy. We find that negative gradients exist as soon as the disk settles at high redshift, and are maintained throughout the long-term evolution of the galaxy, including during major merger events. The inside-out growth of the disk and an o
Objective: Progressive Supranuclear Palsy (PSP) is a severe neurodegenerative disease characterized by tangles of hyperphosphorylated tau protein and tufted astrocytes. Developing treatments for PSP is challenging due to the lack of disease models reproducing its key pathological features. This study aimed to model sporadic PSP-Richardson's syndrome (PSP-RS) using multi-donor midbrain organoids (M
Background: The adoption of eHealth accelerated during the COVID-19 pandemic. Inequalities in the adoption of eHealth during the COVID-19 pandemic have been reported, but there are few such studies among people with impairment. Objectives: This study aimed to investigate self-reported use and difficulty in the use of eHealth before the COVID-19 pandemic compared to during late social distancing re
This thesis analyses how welfare, entitlement and welfare subjects are discursively constructed in the policy process surrounding the proposed qualification requirements for social insurance benefits and financial assistance, as part of the Swedish social benefit reform, ‘bidragsreformen’. Drawing on Norman Fairclough’s three-dimensional model of discourse analysis, the study examines the governme
I detta examensarbete, numeriska simuleringsverktyg- CFD och FEM- användes för att beräkna flödet, temperaturfältet och de termiska deformationerna inuti en maskin för försegling av den vertikala kanten av en kartongförpackning. Arket- förpackningsmaterialet har en U-form- matas in i maskinen- side sealer- där varm luft blåses mot båda kanterna av arket. Syftet är att smälta polymer lagret på kanIn this master’s thesis work, numerical simulation tools- computational fluid dynamics (CFD) and finite element method (FEM)- are used to predict the flow, the temperature field and the deformations within a machine for sealing the vertical seam of a carton package. The blank- the packaging material folded as a U-shape- is fed into the machine- the side sealer- where hot air is blown toward both e
Background: Local networks have been recognized for their potential to govern collaborative action toward a low-carbon future in urban areas, yet there is a need to learn more about the strengths and weaknesses of such governance structures. In this paper we assess the Local Roadmap for a Climate Neutral Building & Construction Industry in Malmö 2030 (LFM30) network which was initiated in 2018
Shifting everyday consumption from linear to circular is a key sustainability challenge, and interventions targeting households and consumers are increasingly promoted as a means to support this transition. However, much remains unclear about the theoretical assumptions that underpin such interventions and how these shape their design and outcomes. This article presents a systematic literature rev
Botulinum-toxin A (BoNT/A) is used for a wide range of conditions. Intramuscular administration of BoNT/A inhibits the release of acetylcholine at the neuromuscular junction from presynaptic motor neurons causing muscle-paralysis. The aim of the present study was to investigate the effect of high dose intramuscular BoNT/A injections (6 UI = 60 pg) on muscle tissue. The gait pattern of the rats was
utomotive systems offer a rich opportunity for hybrid models, controls, and tools. Beyond the traditional use of hybrid models for representing the behavior of the composition of discrete controller and continuous plants, automotive mechanical systems exhibit hybrid behavior as demonstrated in this chapter. In addition, hybrid systems can be used to capture system specifications at the highest lev
The current research focuses in understanding how inlet pressure, EGR, combustion phasing, engine speed and pilot main ratio are affecting the main parameters of the combustion (e.g. efficiency, NOx, soot, maximum pressure rise rate) in the novel concept of injecting high octane number fuels in partially premixed combustion. The influence of the above mentioned parameters was studied by performing
Using alternative fuels like Natural Gas (NG) has shown good potentials on heavy duty engines. Heavy duty NG engines can be operated either lean or stoichiometric diluted with EGR. Extending Dilution limit has been identified as a beneficial strategy for increasing efficiency and decreasing emissions. However dilution limit is limited in these types of engines because of the lower burnings rate of
The behavior of Ethanol and seven fuels in the boiling point range of gasoline but with an Octane Number spanning from 69 to 99 was investigated in Partially Premixed Combustion. A load sweep was performed from 5 to 18 bar gross IMEP at 1300 rpm. The engine used in the experiments was a single cylinder Scania D12. To allow high load operations and achieve sufficient mixing, the compression ratio w
By using a turbo the operating range of the HCCI engine can be increased, but at the expense of increased controller complexity. The dynamics the turbo introduces in the intake and the exhaust manifolds, have a large impact on the in-cylinder mixture temperature, pressure and finally the combustion phasing. To compensate for this and to maintain desired combustion phasing, precise control of the n
For diesel engines the major exhaust problem is particulate matter and NOx emissions. To reduce NOx, exhaust gas recirculation (EGR) is often used. The behavior of the EGR-level will therefore influence the emissions and it is therefore valuable to keep track of the EGR-level. Especially during transients it is difficult to predict how the EGR-level varies. In this paper the CO2-level in the intak
Partially Premixed Combustion (PPC) is a combustion concept by which it is possible to get low smoke and NOx emissions simultaneously. PPC requires high EGR levels and injection timings sufficiently early or late to extend the ignition delay so that air and fuel mix extensively prior to combustion. This paper investigates the operating region of single injection diesel PPC in a multi cylinder heav
A diesel engine developed for an international market must be able to run on different fuels considering the diesel fuel qualities and the increasing selection of biofuels in the world. This leads to the question of how different fuels perform relative to a standard diesel fuel when not changing the hardware settings. In this study five fuels (Japanese diesel, MK3, EN590 with 10% RME, EN590 with 3
Natural gas and hydrogen enriched natural gas has been tested as fuels together with diesel oil and RME in a single cylinder Scania research engine. The gas was introduced as port injection while the diesel was introduced as early direct injection. Because the gas was premixed with air before combustion and the diesel was injected early in the compression stroke, the engine ran close to HCCI mode.
In HCCI you do not have the same control of the combustion like in SI and Diesel engines. Controlling the start of a combustion event is a difficult task and requires feedback from previous cycles. This feedback can be retrieved from ion current measurements. By applying a voltage over the spark gap, ions will lead a current and a signal that represents the combustion in the cylinder will be retri
A piezoelectric micro mass flow controller (MMFC) for liquid fuel injection into a mini-HCCI-motor for power generation is introduced. Piezoelectric actuation ensures negligible power consumption for fuel injection allowing self-sustaining operation. A pressurized fuel tank is connected to the MMFC which is designed like a normally-closed, on-/off-operating valve. Integrated piezoresistors are use
This work has focused on studying the in-cylinder pressure fluctuations caused by rapid HCCI combustion and determine what they consist of. Inhomogeneous autoignition sets up pressure waves traversing the combustion chamber. These pressure waves induce high gas velocities which causes increased heat transfer to the walls or in worst case engine damage. In order to study the pressure fluctuations a
