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Arbetet presenterar en metod som uppskattar ljud så som en människa uppfattar det i ett rum. Metoden kan användas i exempelvis applikationer med augmented reality och brusreducering. Att kunna uppskatta ljud i ett ljudfält är en nödvändighet för många applikationer. I exempelvis aktivt brusreducerade hörlurar får man in en signal som man vill tysta genom att skicka ut en motsatt signal, som i teoThere are different ways of evaluating the sound pressure in a sound field. Doing so is an essential part of several applications, such as active sound control and voice analysis. One way of evaluating the sound pressure in a sound field is by measuring a few discrete points in the field, combined with an interpolation method to find the sound pressure for the remaining field. Recently, it has bee

The field of machine learning has advanced significantly in recent decades, and, at the same time, computational power has improved to the point where training large machine learning models, such as artificial neural networks, is now accessible. Consequently, there has been a rise in the use of these models within the financial sector, with some firms leveraging them to assist with investment deci

This research is concerned with the relation between racism and the notion of rurality. More specifically, it studies a formally defined rural area in France where the State relocated migrants between 2016 and 2019, placing them in a derelict military camp. By so doing, the study contributes to the ongoing debate whether the rural-urban dichotomy should be considered a sufficiently realistic or de

Japanese knotweed (Reynoutria japonica) is a problematic plant species that causes a lot of damage on anthropological constructions as well as ecosystems throughout Europe. Several attempts have been made to control this species, such as glyphosates, cutting/mowing, covering with geoweave and digging, so far with varying degrees of success. In recent times different techniques of heat treatment ha

Algae exhibit different strategies to avoid predation by zooplankton. In green algae, which are generally not known for being toxic, colony formation or a protective mucilage cover can be such defence mechanisms. This study investigates the predation defence of Microglena globulifera (Chlamydomonadales), a unicellular freshwater green alga, against the rotifer Brachionus calyciflorus. Rotifers gro

Vägen till helvetet är kantad av defekta humlor Pollination är avgörande både för grödor och vilda växter, men de senaste decennierna har antalet pollinatörer minskat, särskilt de viktiga humlorna. Humlor får avkomma på ett sätt som gör dem särskilt känsliga för inavel. Jag har prövat två metoder för att upptäcka inavel i två humlearter, mosshumla (Bombus muscorum) och haghumla (Bombus sylvarum),Bumblebees, a pollinator, are haplodiploid with single-locus complementary sex determination (sl-CSD) and as a consequence can give rise to diploid males. Diploid males have previously been found to be associated with high costs and multiple severe effects. Mostly studied on Bombus terrestris, a common species, the frequency of diploid males have been suggested as a measure of inbreeding and there

Human-mediated landscape alterations has led to habitat loss for many pollinator species, causing declines in both diversity and abundance. In addition to habitat loss, habitat fragmentation can reduce population connectivity and lead to declines in genetic diversity, the variation that enable adaptation to novel conditions. In spite of this, to which extent pollinator species have lost genetic di

The trade-off between current and future reproduction is universal and forms the basis of life-history theory. Brood size manipulations is one of the most common way to test this trade-off. Although the effect of brood size manipulation on immune response have been tested in many studies, little is known about baseline innate immune function. To fill this gap, I created three groups (enlarged, red

Organisms must aim to find suitable places to settle and reproduce, and this choice varies according to environmental and individual features. The choice of an adequate place can have crucial repercussions on the reproductive success and thus, animal fitness. In many species natal dispersal is a key process accounting for crucial implications for a species spatial distribution. Hence, natal disper

The sperm whale (Physeter macrocephalus) is a cosmopolitan species with a broad distribution that ranges from the tropics to the poles. Males are known to migrate between nutrient-rich high latitude waters and low latitude breeding grounds. In the North Atlantic, large males are found up to the southern limits of the ice edge. However, their seasonal distribution patterns remain poorly known in th

The creation of floral resources for pollinators, such as flower strips, is seen as a relevant and needed intervention but comes with both cost and an opportunity for farmers. It may be worth it if, for example, pollinators are attracted to pollinator-dependent crops and deliver crop pollination. Unfortunately, since pollinators are mobile organisms, the spatial distribution of crop pollination re

Bumblebees (Bombus terrestris) are central place foragers, that have been shown to use path integration based vectors to navigate their environment. They also have remarkable learning and memory abilities, and can readily learn different cues. Recently, a behavioural assay has been developed that allows for rigorous testing of these mechanisms in a laboratory setting. This thesis aimed to use this

Överdrivet synkroniserade urladdningar i mänskliga hjärnkulturer Under flera decennier har forskare försökt förklara vad det är som sker i hjärnan under ett epileptiskt anfall. Detta tillstånd kännetecknas av att små eller stora populationer av hjärnceller överaktiveras i synkroni under förloppet av sekunder eller flera timmar. En obalans mellan inhibitoriska hjärnceller, som stänger av celler ocHigh synchronicity within cortical circuits resulting from imbalance between excitatory and inhibitory activity is a key feature of epileptiform seizures and different neuronal development stages. The exact mechanism contributing to this activity is still debated but multiple receptors expressed by cortical cells such as Glutamatergic, GABAergic neurons and astrocytes could be involved. With the r

This thesis revisits one of the most prominent contributions to the literature on labour income shares by \citet{blanchard1997} and offers an alternative perspective on the developments in European and Anglo-Saxon countries between 1970 and 2019. Labour shares in both groups of countries declined resulting from changes in relative factor prices and quantities. I find that changes in relative facto

In this project, RAM, we wanted to question today’s consumption of furniture and create furniture with longevity in mind. Explore the possibilities of designing furniture that would grow with you through life to avoid having the need to buy new in different stages of life. The project resulted in a storage system that can adapt to different living situations which can accrue through life. O

Vid byggande, sanering av före detta avfallsdeponier eller liknande företag som påverkar marken krävs noggranna markundersökningar för att kunna utföra arbetet så tids- och kostnadseffektivt som möjligt samt för att minimera miljöpåverkan. Sådana markundersökningar sker inte sällan med hjälp av geofysiska mätmetoder, där seismik är en av dem. Det är vanligt att använda aktiva metoder med exempelvi

Bark beetle attacks have led to widespread tree disturbance and deaths in many parts of the world, and thereby also economic and biodiversity losses. Forest-rich Sweden has experienced periodic attacks, latest in 2018. There is a great interest in identifying the most important explanatory features behind bark beetle attacks and making spatial predictions on where attacks might happen. This could

Gensax löser gåta om cellandning Gensaxen CRISPR-Cas9 är ett användbart redskap för att studera proteiner och deras funktioner. Den tillåter modifikationer att göras på specifika positioner på DNA som kan resultera i olika varianter av proteiner. Dessa varianter kan studeras och slutsatser kan dras om deras funktioner. Här utvärderas en CRISPR-Cas9-baserad metod, samt används för att studera samm

Plastic production and disposal have excessively contributed to climate change and other environmental problems. Therefore, the green route for the production of recyclable polymers, which is industrially and economically practical, is indispensable. 2,5-furan dicarboxylic acid (FDCA) synthesised from 5-Hydroxymethylfurfural (HMF) is a new alternative biobased resource for polymers. FDCA has been

T-celler – kroppens eget försvar för att besegra barncancer I Sverige drabbas runt 350 barn av cancer varje år. En variant av barncancer där tumörerna ofta uppstår på binjurarna och påverkar nervsystemet är neuroblastom (NBL). I det här projektet har vi studerat hur immunförsvaret och då mer specifikt hur mördar-T-cellerna kan användas för att bekämpa cancern. Genom att hitta nya målproteiner somNeuroblastoma (NBL) is the most common pediatric extracranial solid tumor and often manifests in the adrenal gland affecting the sympathetic nervous system. Despite many treatment alternatives, the risk of relapse remains, and the overall five-year survival is around 50 %. By downregulating major histocompatibility complex I (MHC-I), the NBL cells can evade the immune system affecting the function