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Vid avdelningen för kärnfysik utvecklas för närvarande andra generationens Ir-koincidensspektrometer. Anledningen till detta är att det finns ett stort behov bland geologer att mäta spårkvantiteter av Iridium i olika geologiska skikt för att korrelera skiktens ålder med eventuella stora meteoritnedslag. Första generationens spektrometer byggde på en dubbelkoincidens mätt med två HPGe-detektorer, mPresently, the development of the second generation Ir coincidence spectrometer is talking place at the division of Nuclear Physics. There is a large need among geologists to measure trace quantities of Ir in different geological layers and correlate the age of the layer with different large meteorite impacts. The first generation Ir spectrometer was based on a coincidence measured by two HPGe det

As passenger cars emissions standards are tightened manufacturers are forced to cut the cars fuel consumption. This can be done in various ways and one of these is to improve a cars aerodynamic attributes, and above all the car's drag coefficient. A part of the car's total drag is from the air passing through the car's engine compartment and cooling system. The air to slow down, rerout

Short chain fatty acids (SCFAs; acetic, propionic and butyric acid) are formed during bacterial fermentation of carbohydrates in the colon. The interest in SCFA production is related to an increasing body of knowledge of the physiological effects of these acids. SCFAs are important anions in the colonic lumen and serve locally as nutrients for the mucosa cells, stimulating mucosal proliferation an

The present work describes the numerical modeling of medium-speed marine engines, operating in a fumigated dual-fuel mode, i.e. with the second fuel injected in the ports. This engine technology allows reducing engine-out emissions while maintaining the engine efficiency and can be fairly easily retrofitted from current diesel engines. The main premixed fuel that is added can be a low-carbon one a

In response to growing criticism of new public management reforms, the Nordic countries have introduced so-called trust reforms aimed at transforming public sector management and leadership. There is, however, scarce knowledge about the role of organizational concepts in national trust reform and how they are translated, not least in a comparative perspective. This study offers an in-depth analysiIn response to growing criticism of new public management reforms, the Nordic countries have introduced so-called trust reforms aimed at transforming public sector management and leadership. There is, however, scarce knowledge about the role of organizational concepts in national trust reform and how they are translated, not least in a comparative perspective. This study offers an in-depth analysi

Digitaliseringen har medfört svåra utmaningar för det nuvarande skattesystemet. Internationell bolagsbeskattning återspeglar tanken att ett företag måste vara fysiskt närvarande för att leverera varor eller tjänster på en marknad. Nya företagsmodeller möjliggör däremot att kunna nå ut till konsumenter utan någon fysisk närvaro. Det nuvarande internationella skatteregelverket gör det möjligt för boThe digitalisation has posed difficult challenges for the current tax system. International corporate taxation reflects the idea that a company must be physically present to deliver goods or services in a market. However, new business models allow companies to interact with consumers without being physically present. The current international tax regulations allow companies to generate significant

Transportsektorn bidrar med en stor mängd utsläpp som påverkar miljön genom bland annat klimatförändring, försurning av mark och sjöar och negativa effekter på organismers hälsa. Ett sätt att minska den negativa miljöpåverkan är att sätta miljökrav vid upphandling av transporter. E.ON Värme Sverige AB (EVS), har i dagsläget uppskattat ca 55 - 75 000 lastbilstransporter per år. Det som främst levThe transport sector contributes with a large portion of emissions that affects the environment in a negative way, such as acidification of the ground and lakes and the health of living organisms. One way to reduce the negative impact is to set environmental requirements when purchasing transport services. E.ON Värme Sverige AB (EVS), estimates that there are approximately 55 - 75 000 transports

I takt med att världen globaliseras allt mer uppstår också nya typer av utma-ningar. Skatteplanering och skatteflykt orsakar idag stor skada på länders skattebas. För att motverka detta har OECD sedan 2013 arbetat med ett pro-jekt som kallas för BEPS (Base Erosion and Profit Shifting). BEPS består av 15 åtgärder för att motverka erodering av skattebasen och vinstallokering. Projektet har beskrivit

Extremely metal-poor (EMP) stars are an integral piece in the puzzle that is the early universe, and although anomolous subclasses of EMP stars such as carbon-enhanced metal-poor (CEMP) stars are well studied, they make up less than half of all EMP stars with [Fe/H] ∼ -3.0. The amount of carbon depletion occurring on the red giant branch (carbon offset) is used to determine the evolutionary status

We investigate the possibility of finding Earth-like planets in the habitable zone of 34 nearby FGK-dwarfs, each known to host one giant planet exterior to their habitable zone detected by RV. First we simulate the dynamics of the planetary systems in their present day configurations and determine the fraction of stable planetary orbits within their habitable zones. Then, we postulate that the ecc

Large multiobject spectroscopic surveys require automated algorithms to optimize their observing strategy. One of the most ambitious upcoming spectroscopic surveys is the 4MOST survey. The 4MOST survey facility is a fibre-fed spectroscopic instrument on the VISTA telescope with a large enough field of view to survey a large fraction of the southern sky within a few years. Several Galactic and extr

The stellar-to-halo mass relation (SHMR) is not only one of the main sources of information we have on the connection between galaxies and their dark matter haloes, but also an important indicator of the performance of galaxy formation models. Here, we use one of the largest sample of galaxies with both high-quality rotation curves and near-infrared surface photometry, and perform a detailed compa

The detections of 1I/‘Oumuamua and 2I/Borisov within just two years of each other impressively demonstrate that interstellar objects (ISOs) must be common in the Milky Way. Once released from their parent system, these ISOs travel for billions of years through interstellar space. While often imagined as empty, interstellar space contains gas and dust most prominent in the form of molecular clouds.

Supersonic gas turbulence is a ubiquitous property of the interstellar medium. The level of turbulence, quantified by the gas velocity dispersion (σg), is observed to increase with the star formation rate (SFR) of a galaxy, but it is yet not established whether this trend is driven by stellar feedback or gravitational instabilities. In this work, we carry out hydrodynamical simulations of entire d

We use data from the 17th data release of the Apache Point Observatory Galactic Evolution Experiment (APOGEE 2) to contrast the chemical composition of the recently discovered Gaia Enceladus/Sausage system (GE/S) to those of 10 Milky Way (MW) dwarf satellite galaxies: LMC, SMC, Boötes I, Carina, Draco, Fornax, Sagittarius, Sculptor, Sextans, and Ursa Minor. Our main focus is on the distributions o

Wind-abraded cobbles (ventifacts) and aeolian sand are known from the sandy-gravelly coastal areas of south-western Sweden, especially in association with raised deltas. Ventifacts are recorded on at least two different stratigraphic levels, at some sites atop glaciofluvial sediment, at other sites atop littoral deposits, and in some places at both levels, while aeolian sand usually forms a surficWind-abraded cobbles (ventifacts) and aeolian sand are known from the sandy-gravelly coastal areas of south-western Sweden, especially in association with raised deltas. Ventifacts are recorded on at least two different stratigraphic levels, at some sites atop glaciofluvial sediment, at other sites atop littoral deposits, and in some places at both levels, while aeolian sand usually forms a surfic

Popular Abstract in English Parkinson’s disease (PD) is the second most common, after Alzheimer’s disease, neurodegenerative disease in man. Stiffness in joints, shaky hands, and slowness of movements make it difficult for people with PD to complete normal daily tasks like buttoning up a shirt. Additionally, PD affects memory, mood, sleep and the function of the gastro-intestinal tract. Over time,Parkinson’s disease (PD) is currently the second most common neurodegenerative disorder (after Alzheimer’s disease). PD is diagnosed on its motor symptoms, which include akinesia, bradykinesia, rigidity, postural imbalance and resting tremor. It is well established that the motor symptoms develop due to lack of dopamine in the striatum. This is caused by progressive degeneration of dopaminergic ne

Popular Abstract in Swedish En ny metod för att syntetisera avancerade kolhydrater har utvecklats. I en utvärdering har två kolhydratstrukturer, viktiga intermediat i ett nytt cancervaccin, syntetiserats.