Evolution of sex chromosomes in Sylvioidea songbirds

Sex chromosomes were discovered more than 100 years ago. They have been studied intensely from a theoretical perspective since then, giving rise to a large body of testable predictions about their evolution from autosomes. A common feature of sex chromosomes is recombination suppression between the sex chromosome copies (X and Y in male heterogametic systems, or Z and W in female heterogametic systems). Without recombination, the sex-limited chromosome (Y or W) is expected to degenerate through the accumulation of deleterious mutations and repeat elements. Over long evolutionary time scales, this degeneration may leave the Y/W chromosomes short and almost completely devoid of functional genes.Using genome sequencing technology, we can now study the full DNA sequence of sex chromosomes. The analysis of sequence data from a wide range of taxonomic groups has revealed that sex chromosomes are more dynamic and variable than previously believed. Several aspects of sex chromosome evolution, however, remain poorly understood, especially relating to the early stages of evolution from autosomes. This is partly because some hypotheses are challenging to test, but also because most well-studied sex chromosome systems are evolutionarily old and biased towards XY systems.In this thesis, I study the evolution of sex chromosomes across Sylvioidea songbirds using genomic data and bioinformatic methodology. All members of this superfamily have a shared “neo-sex chromosome”: a fusion between an autosome (chromosome 4A) and the existing sex chromosomes. The sex chromosomes of birds (ZW) formed in a common ancestor more than 100 million years ago. Since then, the W chromosome has undergone severe degradation and shortening, obscuring almost all traces of their early evolution. Additions of new genetic material through autosome-sex chromosome fusions, however, allow us to study the early stages of sex chromosome evolution.I developed a computational pipeline aimed at discovering and visualizing sex chromosomes. I applied this pipeline to genomic data from species belonging to 13 different Sylvioidea families, and found that four additional autosome-sex chromosome fusions have occurred in different lineages within the group (involving chromosomes 3, 4, 5 and 8). These different fused regions have intermediate to extremely low W degeneration levels, with dosage sensitive and evolutionarily constrained genes being retained to a higher degree than other genes. I also studied the structure of these neo-sex chromosomes, how female gene expression changes in response to W degeneration and how recombination suppression extends along newly added sex chromosome regions. The work in this thesis shows that Sylvioidea songbirds are an ideal system for testing theory relating to sex chromosome evolution, and that bird sex chromosomes are more variable than previously believed

Early life and its implications for astrobiology : a case study from Bitter Springs Chert, Australia

Early life research faces additional challenges than those of the study of later life forms. Due to the de-materialization of the earliest rocks, valuable information about the early Earth is forever lost. Furthermore, early life was small and morphologically basic, effectuating abiotic pseudofossils to infiltrate the fossil record. A central theme is the close connection early life research share with astrobiology, manifested by the notion that early terre-strial life research should be conducted with as much vigilance as potential fossil findings from a remote planet. Both fields benefit from a broad-minded approach as the basic building blocks of life, previously thought to be pre-sent in all life forms, might have room for interchangability. Therefore, the biomarkers traditionally searched for might not reveal the full story of life. Petrography, XRF, SEM and FTIR was applied to rocks from Bitter Springs Formation, Australia, in hope to detect biogenic material. Hydrocarbons were detected in one of the samples thro-ugh FTIR analysis, which is a strong indicator for biogenicity. Many structures were found that are most probably bacterial fossils and oncoid structures.Forskning kring tidigt liv möter svårigheter utöver de som forskning kring senare liv ställs inför. På grund av att de tidigaste bergarterna inte finns bevarade har viktig information om jordens tidiga förhållanden för evigt gått förlorad. Dessutom var de tidigaste livsformerna små och morfologiskt enkla, vilket betyder att abiotiska pseudofossil lätt kan infiltrera fossilarkivet. Ett centralt tema är den nära kopplingen mellan forskning kring tidigt liv och astrobiologi, delvis på grund av att tidigt liv på jorden måste undersökas med samma hårda krav som vi skulle ställa på potentiella fossil från andra planeter. Båda forskningsfälten gagnas av vidsynthet då det är möjligt att de byggstenar vi traditionellt sett kopplat till livsformer kan bytas ut mot andra ämnen. Det är därför möjligt att sökandet efter traditionella biomarkörer inte räcker till för att klarlägga livets fulla historia. Petrografiska undersökningar, XRF, SEM och FTIR applicerades på stuffer från Bitter Springs Formation, Australien, för att se ifall deinnehöll biologiskt material. Kolväten hittades genom FTIR-analys, vilket är en stark bioindikator. Flera strukturer hittades som högst troligtvis är fossila bakterier och oncoider

The citizens’ perspective : awareness, feelings and acceptance of surveillance and surveillance systems for fighting crime in Sweden. A quantitative study

This document presents the results for Sweden within the framework of a larger study undertaken as part of the RESPECT project – “Rules, Expectations and Security through Privacy-enhanced Convenient Technologies” (RESPECT; G.A. 285582) – which was co-financed by the European Commission within the Seventh Framework Programme (2007-2013). Analyses are based on a survey regarding the perceptions, feelings, attitudes and behaviours of citizens towards surveillance for the purpose of fighting crime, carried out amongst a quota sample that is representative of the population in Sweden for age and gender. Responses were gathered, predominantly, through an online survey supplemented in some partner countries by a number of questionnaires administered in face to face interviews, in order to fulfil the quota and also reach those citizens who do not use the internet. The questionnaire consisted of 50 questions and was available online in all languages of the European Union between November 2013 and March 2014. The Swedish sample is based on the responses from 170 individuals who indicated Sweden as their country of residence. As a result, the Swedish respondents indicated a strongly felt lack of trust in the protection of, and control over, personal information gathered via surveillance. Further, the majority of respondents feel more unhappy than happy with the different types of surveillance (except CCTV), and they feel also unhappy about surveillance taking place without them knowing about it. Additionally, there is a rather strong link between feeling happy, or unhappy, about surveillance and feeling secure or insecure through the presence of surveillance. A large number of Swedish respondents appear to have two distinct, and very different, reactions to surveillance. Some people feel secure in the presence of surveillance, but in others surveillance produces feelings of insecurity. However, the majority of respondents feel more insecure than secure due to surveillance measures. Analyses also indicate that increasing the perceived effectiveness of surveillance measures as well as increasing the perceived effectiveness of laws regarding the protection of personal data gathered via surveillance may make citizens feel more secure. More research is needed to disentangle the relationships and effects between surveillance measures, feelings of security or insecurity, and citizens’ general quality of life feelings.This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 285582.peer-reviewe

Dense sampling of bird diversity increases power of comparative genomics (vol 587, pg 252, 2020)

Publishe

Time pressure and performance in Puzzle games : Stress, performance and entertainment value

Denna studie är framtagen för att utforska egenskaperna hos tidspress i ett pusselspel och om den har en effekt på spelare. För att utvärdera om tidspress har en märkbar effekt på spelare så kommer studien att analysera fenomenet i relation till tre primära kategorier: tidseffektiviteten, beslutstagandet och hur underhållande momentet var för spelaren. För att kunna mäta de skillnader tidspress har på spelare så delades testpersonerna in i två grupper. En grupp som blir utsatta för tidspress under testsessionerna och en som inte blir det. Studiens resultat  pekar på att tidspress har en tydlig påverkan på spelare som blir utsatta för den vad gäller deras prestation. Resultatet på hur spelare blir påverkade är dock dubbeltydigt och de två utvärderingsmodellerna ger resultat skiljer sig från varandra markant

Att börja från noll? : en studie av hur olika pedagoger lär ut komposition till nybörjare

Syftet med detta examensarbete är att ta reda på hur man kan arbeta med elever/deltagare som saknar förkunskaper i låtskrivande. I denna studie har jag använt mig av kvalitativa intervjuer med ett par musikpedagoger och av tidigare forskning som berör ämnet. Kapitlet om tidigare forskning innefattar litteratur som berör kreativitet, frågan om huruvida vi alla har förkunskaper eller inte, eventuellt användande av digitala verktyg, musikskapande i skolan och andra närliggande begrepp. Den tidigare forskningen ställs sedan mot resultatet i diskussionskapitlet. Undersökningen utgår inte från skolans musikundervisning och dess läroplan utan fokuserar istället på hur man rent generellt kan arbeta med nybörjare och komponerande. Jag vill undersöka och förhoppningsvis få verktyg i hur man lär ut skapande av musik, av att skriva låtar. Slutsatserna av min undersökning visar på det komplexa arbetet pedagoger utför för att få elever och kursdeltagare att komma igång, hitta inspiration och kreativitet rörande låtskriveri. Flexibilitet, lyhördhet och innovationsförmåga verkar vara tillgångar som är essentiella för pedagogers undervisningssituation

Semesterrätt

Juridikbok.seCC-BY-NC 4.0</p

Semesterrätt

Juridikbok.seCC-BY-NC 4.0</p

Maintaining well-being when working remotely : Work habits of employees at a geographical IT office in Sweden during the COVID-19 pandemic, their perceived well-being and productivity

The COVID-19 pandemic has in many ways changed how we live our lives. As a means to decrease the risks, working at a distance is now common for most employees during the pandemic. A problem that has arisen is getting overall information on how employees well-being and productivity has been affected by the new forced work environment. The primary part of this study is to identify the current effects of remote work on employees at an engineering consultancy company, active in the field of consulting engineering, environmental technology and architecture in Sweden through a web-based survey and compare the results to previous studies on the subject of remote work. A secondary objective of this study was to develop a smartphone application with the goal of increasing the physical activity of employees currently working from home. A secondary part of this study was to identify a problem specific to remote work, and to come up with a technical solution to the problem through prototyping, development and testing. The survey's results revealed that Sweco management (where the survey was conducted) provided sufficient resources in order to preserve and enhance the general well-being of its workers who currently work from home, but they struggled to distinguish work and home life, as do many others in similar circumstances. Respondents also reported a higher workload and less physical exercise during the work day. Employees at the company reported higher levels of well-being and productivity than participants in other international studies. Although the company has taken precautions to improve the working conditions of its workers, further research into the subject is encouraged to see whether they stand out in their investment in their employees' well-being or whether they are simply following the pattern set by other businesses in the same sector