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  • Disputation: 2023-12-01 10:00 hörsal 2, hus A, Södra huset, Stockholm
    Zell, Jeremy L.
    Stockholms universitet, Juridiska fakulteten, Juridiska institutionen.
    Excess of Mandate in International Commercial Arbitration Law: A Comparison of the US Federal Arbitration Act and the Swedish Arbitration Act2023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This study analyzes the concept of “excess of mandate” as a ground for set-aside in International Commercial Arbitration Law. In particular, it compares the US courts’ application of the concept in US law with Swedish courts’ application under Swedish law.

    The study employs a standard comparative model. It examines the legal history, case law, statutory law, and legislative history of the two jurisdictions. The study seeks to identify, among other things, factual circumstances that would constitute excess of mandate in both jurisdictions, or lead to differing court rulings in each jurisdiction. Hypothetical scenarios are also used to identify unique and similar outcomes depending on the circumstances of a given case and the way in which the two different court systems apply the concept of excess of mandate.

    The study concludes that, despite the fact that excess of mandate is treated as a wide-spread international concept in international arbitration, the concept’s application can vary greatly from jurisdiction to jurisdiction. This is due to, among other things, a given legislature’s purpose for writing the concept into national law and each jurisdiction’s procedural law traditions and practices.

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    Excess of Mandate in International Commercial Arbitration Law: A Comparison of the US Federal Arbitration Act and the Swedish Arbitration Act
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  • Disputation: 2023-12-01 13:00 Vivi Täckholmsalen (Q-salen), NPQ-huset, Stockholm
    Jie, Vun Wen
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    How the sensory ecology of the bumblebee affects their functional traits2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Morfologiska egenskaper är viktiga för egenskapsbaserade ekologiska studier eftersom de möjliggör förutsägelse av biologisk mångfald över hela biosfären. För närvarande tillämpas inte den prediktiva kraften hos egenskapsbaserad ekologi ofta på landlevande leddjur, även om de ger oss viktiga jordbruksmässiga, ekologiska och kulturella värden. Syftet med min doktorsexamen var att studera hur funktionella morfologiska egenskaper hos humlor är kopplade till olika miljöfaktorer.Att förbise intraspecifika variationer av funktionella morfologiska egenskaper i egenskapsbaserad ekologi är vanligt och kan leda till att en art underskattar anpassningsförmågan.

    I kapitel I använde vi allometri för att jämföra skalförhållandet mellan tre olika organ (sammansatta ögon, vingar och antenner) bland polymorfa arbetare i storleken hos den gulstjärtade humlan, Bombus terrestris. Vi använde 12 kolonier varav hälften utvecklades vid en suboptimal förhöjd temperatur (32°C, snarare än 25°C). Vi fann att varje koloni hade en specifik skalningsprofil för varje organ och dessa skillnader kunde inte tillskrivas temperaturstress. Variabiliteten i skalning mellan kolonier antyder en intraspecifik flexibilitet i investeringar i funktionella morfologiska egenskaper.

    I kapitel II utvecklade jag en metod för att uppskatta storleken på dorsal rim area (DRA), en specialiserad region i det sammansatta ögat av B. terrestris. DRA har varit mycket understuderat på grund av bristen på enkla och högeffektiva metoder för att studera den. Min metod omfattar användningen av 2D-fotografering och mikrodatortomografi (mikro-CT) för att bestämma storleken på DRA och egenskaperna hos dess ommatidiala strukturer. Med min metod utförde jag en allometrisk studie på skalningen av DRA med kroppsstorlek i B.terrestris och fann att kristallina koner av DRA är betydligt mindre jämfört med andra regioner i ögat.

    I kapitel III jämförde jag synsystemen (sammansatta ögon, DRA, ocelli) hos arbetare hos fyra olika humlor (B. jonellus, B. pratorum, B. hypnorum och B. monticola). Dessa arter finns i olika livsmiljöer och jag fann att detta återspeglas i deras visuella systeminvestering. Arter som lever i skogar investerade mer i sina visuella system jämfört med arter som finns i öppna eller öppna/skogsklädda miljöer. Vår studie tyder på att habitatpreferenser verkligen kan forma det visuella systemet hos olika humlor.

    Humlor förekommer ofta sympatiskt och vi studerade deras samexistens i en hemiboreal skog med en begränsad variation av blomresurser. Humlor kan undvika konkurrens genom att söka föda vid olika tider på dygnet. För att identifiera de egenskaper som kan möjliggöra denna samexistens, kombinerade vi heldagsövervakning av humlesamhällen med detaljerade funktionella egenskapersmätningar i kapitel IV. Vi fann att temperaturen påverkade närvaron och frånvaron av arter medan ljusintensiteten påverkade mängden individer och antyder att detta mönster kan kopplas till visuella och termoregulatoriska egenskaper.

    Mina kombinerade resultat visar att humlor är ett utmärkt modellsystem för att studera egenskaper-miljö-relationer eftersom de uppvisar (i) intraspecifika skillnader i egenskaper, (ii) idiosynkratiska och allestädes närvarande egenskaper som DRA, (iii) tydliga egenskaper-miljö-relationer, och (iv) ett exempel på hur egenskaper underlättar samexistensen av liknande arter.

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    How the sensory ecology of the bumblebee affects their functional traits
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  • Disputation: 2023-12-01 13:00 De Geersalen, Geovetenskapens hus, Stockholm
    Hamm, Alexandra
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Permafrost Groundwater Dynamics: Modeling of vertical and lateral flows in the active layer across multiple scales2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Hydrological processes in the Arctic are profoundly influenced by the presence of permanently frozen ground, known as permafrost. Conversely, permafrost is greatly affected by hydrological changes resulting from climate change. Understanding and accurately representing the processes causing permafrost thaw is essential for evaluating the consequences of climate change on permafrost landscapes. In this thesis, I explore how water movements in permafrost landscapes affect the thermal state of the ground and the potential of groundwater flow to transport both heat and solutes. As groundwater is inherently difficult to observe in field experiments, the main method in this thesis is simulating permafrost dynamics with a state-of-the-art physics-based numerical model. Modeling allows investigating these dynamics in both space and time. Results show that an increase in summer rainfall and the associated vertical movement of water in the soil causes opposing effects in the ground temperature response. While enhanced summer rainfall likely leads to a warming in continental permafrost landscapes, in maritime landscapes it may cause a cooling of the ground. This is governed by the effects of rainfall on the hydrothermal properties of the soil and how efficiently it conducts and stores energy.

    Lateral water movement was found to substantially affect soil moisture distribution along a hillslope underlain by continuous permafrost. Soil moisture is important in the context of the hydrothermal properties within a hillslope but also for the capability of the ground to transport solutes. High soil moisture leads to higher soil hydraulic conductivity and therefore affects how fast solutes such as dissolved organic carbon can be transported with the groundwater. Depending on the vertical location of solutes within the soil, this determines the travel time of solutes in the groundwater towards surface water recipients. Additionally, depending on the rate at which air temperatures will increase in the future, permafrost carbon may experience different modes of lateral transport and residence times in the soil. This thesis highlights the complex interplay between permafrost and hydrology and why it is important to study them as a coupled system in order to fully understand the impacts of climate change on the fate of permafrost. 

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    Permafrost Groundwater Dynamics
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  • Disputation: 2023-12-01 13:00 hörsal 8, hus D, Stockholm
    Beyene, Abraham Kumsa
    Stockholms universitet, Humanistiska fakulteten, Institutionen för ämnesdidaktik.
    Obstacles to students' learning of the limit concept: A comparative study2023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This thesis explores obstacles to students’ learning of the limit of a function as students learn the concept in post-compulsory schools in two culturally different contexts, namely Sweden and Ethiopia. The study investigates obstacles to students’ learning of the intuitive limit concept (the limit concept that is based on the intuitive definition) taught in upper secondary schools of these two contexts and characterises the nature of these obstacles. Additionally, the study compares the obstacles identified in the two contexts.

    The study uses a collective instrumental case study approach. Data were collected through teacher interviews before and after lessons, lesson observations, student group interviews, and analysis of textbooks and official documents such as curricula and syllabi.

    The study employed an eclectic conceptual framework that considers the mathematical content, the didactical aspects (teaching) and the students. The study identifies three main categories of obstacles: epistemological obstacles (EOs) arising from the nature of the mathematical concept of limit and other concepts important in limits, didactical obstacles (DOs) arising from teaching practices, and cognitive obstacles (COs) arising from incompatibilities between what is encountered in the lessons and students’ previous knowledge. Within each category, the study lists specific obstacles within each case and then compares and contrasts these. The analysis reveals the dependence of some obstacles on the culture of teaching and the context, particularly DOs and COs. The study also highlights the interplay between different specific obstacles and how the presence of one obstacle can contribute to the occurrence of another. Some of the interplays between some of the specific obstacles seem more common in one of the contexts than the other. For example, in the Swedish case, it was more common that the didactical choices acted on the epistemological obstacles in such a way that didactical obstacles were generated, which then played a role in the occurrence of some cognitive obstacles. This was summarised symbolically as EO→D→DO→CO. On the contrary, in the Ethiopian case, it was more common that the didactical choices impacted on how students understood an idea, which then resulted in the occurrence of cognitive obstacles. This was summarised symbolically as EO→D→C→CO. Thus, the study finds that EOs can be reinforced by the didactical choices reflected in the teaching. Furthermore, the specific EO can have different sources and triggers in the two contexts.

    Considering two culturally different contexts, this study sheds light on the obstacles to students’ understanding of the limit of a function in their learning of the concept. It highlights the influence of the culture of teaching and the context dependence of obstacles, providing insights into how the nature of the concept, teaching practices, and students’ prior knowledge impact on their learning. The study’s findings contribute to filling the gap in previous research of a lack of evidence concerning the interplay between the three forms of obstacles, the role of teaching culture and context on the occurrence of obstacles, and classroom-based comparative studies on the teaching and learning of the limit concept and calculus. The result of the study may also contribute to informing teaching practice and to the development of teaching strategies and curriculum design for improving students’ understanding of the limit concept and other mathematical concepts in general.

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    Obstacles to students' learning of the limit concept
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  • Disputation: 2023-12-01 13:00 hörsal 5, hus B, Stockholm
    Rodríguez Morales, Jorge Ernesto
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för ekonomisk historia och internationella relationer.
    The political economy of adaptation pathways to climate change: An historical institutional approach2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    While there is a growing recognition of the need for societies to adapt to climate change, adaptation governance often falls short and can even worsen existing vulnerabilities. This problem is exacerbated by the deep connection between climate change and economic system governance. It underscores the importance of gaining a better understanding of how economic governance influences adaptation pathways. However, this intricate interplay remains relatively unexplored in the realms of both global governance and climate adaptation research.

    This thesis seeks to address this gap in the existing literature by adopting a historical political economy approach. This approach helps us comprehend how adaptation is governed within the context of historically formed 'glocalized' regimes and sheds light on why adaptation pathways may inadvertently exacerbate vulnerabilities. The research considers how vulnerabilities and adaptation pathways are deeply embedded in glocalized regimes and how historical processes constrain transformative changes while explaining instances of maladaptation. The thesis explores the argument empirically by relying on extensive fieldwork material and document analysis in three Latin American countries: Brazil, Peru, and Uruguay. These countries have economies heavily reliant on extractive sectors like mining and agriculture, which play pivotal roles in their economic histories and are associated with local vulnerabilities and socio-environmental impacts.

    The results suggest that climate responses are not exogenous to the glocalized capitalist regimes but adaptation pathways are, in fact, driven by extractive capitalism. Furthermore, the results show how dominant scientific frames are deployed in both the production of knowledge and the adaptation responses to climate impacts and vulnerabilities. These responses tend to marginalize discussions about the transformative changes necessary for tackling climate change and vulnerabilities under the influence of extractive capitalism. By revealing and analyzing these structural dynamics, this thesis contributes significantly to climate adaptation and global governance scholarship.

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    The political economy of adaptation pathways to climate change
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  • Disputation: 2023-12-01 15:00 Air & Fire, SciLifeLab, Solna
    Persson, Emma
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Big data networks and orthology analysis2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Understanding biological systems in complex organisms is important in life science in order to comprehend the interplay of genes, proteins, and compounds causing complex diseases. As biological systems are intricate, bioinformatics tools, models, and algorithms are of the utmost importance to understand the bigger picture and decipher biological meaning from the vast amounts of information available from biological experiments and predictions. Bioinformatics programs and algorithms do not only depend on information from experiments, but also on information generated from other tools in order to draw accurate conclusions and make predictions. 

    Prediction of orthologs, genes having a common ancestry, separated by a speciation event, are important building blocks for a wide variety of tools and analysis pipelines, as they can be used to transfer gene function between species. Orthologs can for example be used to map genes of model organisms to genes in humans in studies of drug targets. They are extensively used in functional association networks in order to transfer information between species. Functional association networks are models of associations between genes or proteins, where associations can be derived from experimental evidence of different types, from the species itself, or transferred from other species using orthologs. The networks can be used to explore the context and neighbors of a gene, but also for a variety of higher-level analyses, e.g. network-based pathway enrichment analysis. In pathway enrichment analysis the networks can be utilized to contextualize experimental gene sets and annotate them with biological functions. As these tools depend on each other, it is of great importance that the networks used in pathway enrichment analysis are comprehensive and accurate, and that the orthologs used in the networks are relevant and significant. 

    In this thesis, the development and improvement of five bioinformatics tools within three areas of bioinformatics are presented. Despite the tools residing within slightly different areas, they all rely on each other, and can all on different levels improve our understanding of biological functions and biological meaning, from the level of orthology analysis to functional association networks to pathway enrichment analysis.

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    Big data networks and orthology analysis
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  • Disputation: 2023-12-02 10:00 Hörsal 12, Hus F, Stockholm
    Bengtsson, Andreas
    Stockholms universitet, Humanistiska fakulteten, Institutionen för Asien- och Mellanösternstudier (IAM).
    The effects of extramural language: Relationships between engagement in Japanese language activities and general Japanese language proficiency2023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [sv]

    Många andraspråksinlärare upplever att de främst lär sig sitt målspråk genom att använda det utanför klassrummet. Detta ämne, språkinlärning som ett resultat av extramural språkanvändning, har fått ökad uppmärksamhet under det senaste decenniet, men det är fortfarande brist på forskning om detta ämne, och de studier som finns har enbart fokuserat på ögonblicksbilder av enskilda grupper av inlärare på liknande språkkunskapsnivåer med engelska som målspråk.

    Den här studien undersöker sambandet mellan extramural japanska och allmän japansk språkfärdighet hos vuxna inlärare som studerar på universitetet i Sverige kvantitativt. Den gör det både som ett tvärsnitt, genom att jämföra fem grupper med olika kunskapsnivåer för att undersöka den modererande effekten av språkkunskap på en makronivå, och longitudinellt, för att gå bortom korrelationer och ge empiriska data om orsakssamband. Totalt samlades data in från 168 personer, varav ett flertal deltog i studien vid flera tillfällen och olika kunskapsnivåer, under en period på två och ett halvt år. Data analyserades med icke-parametriska korrelationer och bayesiansk regression.

    Resultaten visar att deltagarna ägnade sig åt extramural japanska under ett stort antal timmar varje vecka. Vissa former av japansk språkanvändning (t.ex. textläsning och samtal ansikte-mot-ansikte) var relaterade till allmän japansk språkfärdighet, medan andra inte var det (t.ex. lyssna på musik och titta på videor med undertexter på målspråket). Dessa samband var i huvudsak positiva, även om samband som var negativa eller både positiva och negativa i olika fall förekom. Kunskapsnivån var en modererande faktor, och olika former av språkanvändning hade varierande koppling till allmän japansk språkfärdighet beroende på deltagarnas kunskapsnivåer. Dessutom tyder resultaten på att extramural användning av andraspråket påverkade språkfärdighet, men språkfärdighet påverkade inte i hög grad extramural användning av andraspråket. Detta är bland de första studierna som visar en sådan kausal effekt empiriskt.

    Sammanfattningsvis gör studien betydande bidrag till vår förståelse av sambandet mellan extramural användning av andraspråk och språkfärdighet. Dessutom ger resultaten indikationer på tillämpligheten av resultaten från studier på ett språk för språkinlärning på andra språk. Utöver detta erbjuder studien en innovativ forskningsram för att undersöka extramural andraspråksanvändning, som bör vara robust och giltig oavsett målspråk.

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    The effects of extramural language: Relationships between engagement in Japanese language activities and general Japanese language proficiency
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  • Disputation: 2023-12-07 13:00 De Geersalen, Geovetenskapens hus, Stockholm
    Roth, Nina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Grasslands in a changing climate: Summer drought and winter warming effects on grassland vegetation2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Grasslands harbour a high biodiversity of both plants and animals, and they provide many ecosystem services such as fodder production, pollination, and carbon storage. Climate change is likely to alter grassland ecosystems, with the effects varying according to the exact nature and timing of changes. Hence, understanding of seasonal climate change effects on grasslands and how negative impacts can be reduced is important to maintain biodiversity and to ensure continued delivery of ecosystem services.

    In this thesis I explored how seasonally specific aspects of climate change, i.e. summer drought and winter warming, affect aboveground plant biomass, plant community composition, and floral resources for pollinating insects. Moreover, I aimed to outline ways to mitigate potential negative climate change effects by adapting conventional grazing and mowing regimes and/or by applying soil amendments (i.e. compost) as a novel management method. Soil amendments have been suggested as a method to increase carbon sequestration and they might mitigate negative drought effects. However, there is no empirical evidence of how European grassland ecosystems would be affected should such measures be applied.

    A literature review of climate change studies revealed that the terms ‘wetter’ and ‘drier’ can be defined by a variety of hydroclimatic variables, or are not defined at all, making it difficult to synthesise climate change effects on ecosystems and societies. In two in-situ experiments I investigated the effects of summer drought (using rain-out shelters), soil amendments and mowing on four Swedish grasslands, and the effects of winter warming (using open-top chambers) and sheep grazing on three British Upland grasslands. The experimental summer drought caused a non-significant decline in aboveground plant biomass (i.e. fodder production), plant species diversity, and floral resources. Applying soil amendments increased aboveground plant biomass and floral resources (in yearly mown plots), but these positive effects were reduced under drought. There were signs of negative soil amendment effects on legumes. Winter warming led to an increase in graminoid biomass and a decrease in bryophyte biomass. Sheep grazing buffered the growth of a competitive species under winter warming but had only minor effects overall.

    My thesis emphasizes that it is important to clearly define terms like ‘wetter’ and ‘drier’ when studying effects of climate change on ecosystems, since clarifying the effects of climate across habitats and management interventions will require the synthesis of results across a range of experimental and observational systems. My field experiments indicate that even relatively small climatic changes affect grassland plant biomass and biodiversity, and that these effects depend on the season and grassland site in question. Furthermore, soil amendments have mainly positive effects on the grassland vegetation, indicating that they have potential for broad-scale application as a method to increase carbon sequestration. Given that my experiments were set up in-situ in grasslands and the treatments were rather mild and realistic in magnitude according to local climate change predictions, the observed vegetation changes within only three years are quite remarkable. They therefore highlight the need for detailed empirical and mechanistic understanding of how climate change processes are likely to affect grassland ecosystems.

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    Grasslands in a changing climate: Summer drought and winter warming effects on grassland vegetation
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  • Disputation: 2023-12-07 13:00 sal FB52, AlbaNova universitetscentrum, Stockholm
    Berkowicz, Sharon
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    The Role of Molecular Heterogeneity in the Structural Dynamics of Aqueous Solutions2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The liquid-liquid critical point hypothesis suggests that liquid water exists in two liquid states with different local structures, so-called high- and low-density liquid (HDL, LDL). At ambient pressure water locally fluctuates between these two states, with the fluctuations becoming more pronounced as the liquid is supercooled. In this thesis, we explore the role of molecular heterogeneity in the structural dynamics of aqueous solutions, specifically investigating the interplay of different solutes in water with the hypothesized HDL-LDL fluctuations. In our experimental approach, we utilize coherent light and X-ray scattering techniques, including small- and wide-angle X-ray scattering (SAXS, WAXS), as well as correlation methods, such as dynamic light scattering (DLS) and X-ray photon correlation spectroscopy (XPCS), that enable us to probe structural dynamics at a broad range of length and time scales. 

    Using DLS, we measure the diffusive dynamic behaviour of differently sized nanomolecular probes in supercooled water, finding that it is effectively similar and independent of probe size down to molecular scales of ≈1 nm. In contrast to single water molecules, these probes experience a similar dynamic environment, which coincides with the bulk viscosity. These results could suggest that anomalous influence from the hypothesized water fluctuations becomes apparent first on sub-nm length scales. Furthermore, we explore how the presence of small polar-organic solutes modulates the water phase diagram, utilizing glycerol-water solutions as a model system. By outrunning freezing with the rapid evaporative cooling technique, combined with ultrafast X-ray scattering at X-ray free-electron lasers (XFELs), we are able to probe the liquid structure in deeply supercooled dilute glycerol-water solutions. Our findings indicate the existence of HDL- and LDL-like fluctuations upon supercooling, with a Widom line shifted to slightly lower temperatures compared to pure water. Further experiments on deeply supercooled glycerol-water solutions at intermediate glycerol concentrations, combining WAXS and SAXS/XPCS, provide additional insights. These results reveal a first-order-like liquid-liquid transition involving discontinuous changes in the inter-atomic liquid structure and nanoscale liquid dynamics, which precedes ice crystallization. 

    Lastly, with the aim of developing powerful tools for resolving dynamics within spatially heterogeneous systems, including aqueous solutions, we combine the spatial resolution of nanofocused coherent X-ray beams with dynamic measurements by XPCS. Here, we successfully demonstrate a first proof-of-concept experiment of so-called nanofocused XPCS at MAX IV synchrotron radiation facility. In future experiments, we plan to go beyond standard XPCS at synchrotrons, towards accessing ultrafast atomic-scale liquid dynamics by X-ray speckle visibility spectroscopy (XSVS) at XFELs.

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    The Role of Molecular Heterogeneity in the Structural Dynamics of Aqueous Solutions
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  • Disputation: 2023-12-08 09:30 hörsal 7, hus 4, Albano, Stockholm
    Dorst, Kevin M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Deciphering Carbohydrate Structure: From NMR Chemical Shifts to Conformational Analysis2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Carbohydrates are ubiquitous in nature and exhibit a multitude of roles. Besides nucleic and amino acids, they can be regarded as the third alphabet of life. They are used as energy source to fuel the cells, as structural building blocks and play a key role in cellular recognition processes. Compared to the other two groups of biomacromolecules, carbohydrates display a higher level of structural complexity by virtue of the number of individual monosaccharide building blocks, as well as the greater number of possibilities of connecting them and additional modifications. This renders a high information content and a good understanding of the structure-function relationship of glycans is important, since the presence or absence of specific structures can make the difference between health and disease.

    Carbohydrate structures can be characterized and studied by NMR spectroscopy at the atomic level. This process is time-consuming and error-prone, due to the narrow spectral window, in which most carbohydrate resonances are located leading to severe spectral overlap. Computer programs have been developed, aiding this process. This thesis investigates the quality of prediction of NMR chemical shifts of glycopeptides, highly branched oligosaccharide structures and those bearing a non-natural organic aglycone at the reducing end, as well as the automated determination of primary carbohydrate structures from unassigned NMR spectroscopic data thereof. Novel developments of the CASPER program are highlighted.

    The three-dimensional structure of carbohydrates plays an important role during carbohydrate-protein interactions. This thesis investigates the conformational preferences and dynamics of glycan structures ranging from di- to tetrasaccharides. A particular focus lies on the measurement of transglycosidic 3JCH coupling constants by NMR. Furthermore, the experimental spectroscopic data is compared to results from MD simulations.

    Synthetic carbohydrate chemistry has a strong focus on stereoselective C−O bond formation for the synthesis of oligo- and polysaccharides. Each glycosylation reaction can produce two stereoisomeric structures. To date, the mechanistic pathway of glycosylation reactions is still not fully understood, since many different parameters influence the stereoselectivity. A combined experimental and computational study exploring the role of the solvent is presented and a linear correlation of the selectivity with a solvatochromic parameter for the polarizability of the solvent was found.

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    Deciphering Carbohydrate Structure: From NMR Chemical Shifts to Conformational Analysis
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  • Disputation: 2023-12-08 10:00 Vivi Täckholmsalen (Q-salen), NPQ-huset, Stockholm
    Moradinour, Zahra
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    The sensory morphology of insect pollinators: From structure to behaviour and ecology2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Insektpollinatörer spelar en viktig roll för att balansera våra ekosystem och upprätthålla mångfalden av växter och livsmedel. På grund av antropogena aktiviteter såsom global uppvärmning, förlust och försämring av livsmiljöer, bekämpningsmedel och patogener har många pollinatorpopulationer genomgått drastiska minskningar under de senaste decennierna. Plötsliga förändringar i livsmiljöer kan påverka utvecklingen av insekters sensorsystem och leda till förändringar i deras morfologi, funktion och därigenom beteende. Trots mängden av studier om insektpollinatörer och deras minskande populationer, så förbises ofta effekten av förändrade livsmiljöer på deras sensorsystem. För att fylla denna kunskapslucka studerade jag morfologin hos sensorsystemen hos fjärilar och humlor - två pollinatorgrupper som återfinns i tempererade områden - med avseende på utveckling, beteende, ekologi och anpassning. I Kapitel I använde jag allometri för att studera hur investeringen i sensorsystem varierar inom och mellan olika kön hos fjärilen Pieris napi. Jag mätte storlek och andra parametrar för sensorsystem, inklusive ögon, antenner, snabel och vingar. Jag visade att investeringen i sensorsystem varierar mellan könen och att endast antennlängd och vingstorlek ökar allometriskt med kroppsstorlek. Dessa resultat antyder att inte alla sensorsystem skalar med kroppsstorlek och den energetiska investeringen mellan dem kan variera mellan könen av samma art. I Kapitel II utforskade jag effekten av en suboptimal temperatur på utvecklingen och morfologin av sensorsystem hos P. napi, en ektotherm solitär insekt. Jag exponerade puppor av P. napi för 23°C (optimal temperatur) och 32°C (suboptimal temperatur) och mätte deras kroppsstorlek och storlek på sensorsystemen efter uppkomst. Jag fann att dödligheten var högre vid den suboptimala temperaturen och att uppkomsttiden minskade. Dessutom minskade kroppsstorleken och snabelns storlek hos båda könen, medan antennlängden endast minskade hos hanar. Dessa resultat visar att global uppvärmning kan ha negativa konsekvenser för fjärilars överlevnad och påverka storleken på deras sensorsystem, eventuellt genom att accelerera utvecklingsprocessen. I Kapitel III studerade vi effekten av värmeböljeliknande temperaturer på sensorsystem och beteende hos en annan insektpollinatör, Bombus terrestris. Våra resultat visade att utveckling vid suboptimala temperaturer hade en negativ inverkan på beteendesvar hos humlearbetare. Intressant nog hade den höjda temperaturen ingen signifikant effekt på storleken av deras antenner, ögon och framvingar. Dessa resultat indikerar att en ökad utvecklingstemperatur kan försämra viktiga beteendesvar på sensorsignaler utan att orsaka synliga förändringar i morfologin hos sensorsystemen. I Kapitel IV utforskade jag hur väl den kvalitativa ljusmikromiljön som är förknippad med en utbredningsområde för insekter överensstämmer med noggrant mätta kvantitativa värden. Jag använde tre fjärilarter (P. napi, Pararge aegeria, Vanessa atalanta) som är förknippade med olika ljusmiljöer och har olika spridningsområden. Resultaten visade att endast fördelningen av P. napi påverkades av ljusintensiteten. Investeringen i ögon och hjärnnervvävnad varierade mellan de tre arterna, men denna variation hade ingen tydlig relation till deras kvalitativa eller kvantitativa ljusmiljö. Därför kunde jag visa att noggrann bedömning av ljusmiljöer är avgörande för att förstå och tolka visuella och neurala anpassningar hos insekter.

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    The sensory morphology of insect pollinators: From structure to behaviour and ecology
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  • Disputation: 2023-12-08 10:00 Seminar room, Stockholm Centre for Commercial Law (SCCL), Stockholm
    Skarpsvärd, Marcus
    Stockholms universitet, Juridiska fakulteten, Juridiska institutionen.
    The Costs of Legal Certainty: A Forensically-Informed Methodology on How to Identify the Relevant Costs in Exclusionary Abuse Cases2023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This dissertation examines the forensic relationship between unilateral price practices and prima facie exclusionary abuse(s) under Article 102 TFEU. The research aim is to ascertain relevant cost benchmarks that can be used to determine the legal qualification of a dominant firm’s price practices.

    The research syntheses and results reflect the law in force on the 1 February 2023 and are outcomes of applying the forensic method. The forensic method was applied by systematising the relevant financial data together with the legal sources for the purpose of categorising impugned price behaviours as exclusionary or competition on the merits.

    The research demonstrates, inter alia, that the legal use of cost benchmarks is entrenched in concept of the rule of law by seeking to strike a balance between legal certainty and the effectiveness of Article 102 TFEU. In order to realise this objective, the Court of Justice has constructed three distinct legal tests and depending on which test that is used, it will have a significant impact on which cost benchmark(s) that is to be regarded as relevant. The first is the AKZO test, which is a fixed cost test as it explicitly states which cost benchmarks that must be used. The second is the great bulk of cost test, which is a semi-fixed cost test as it is limited to the objectives that the chosen cost yardstick must realise. The third is the as efficient competitor test, which is an open-ended cost test as it is limited to its aim. However, despite clarifications from the Court of Justice, the law on exclusionary pricing remains complex, ambiguous, and sometimes contradictory. To that end, whilst the research concludes that variable cost is an inappropriate benchmark to apply in service sectors, the research also reveals that lex lata allows for the use of variable cost in a manner which is so extensive that the cost yardstick ultimately will apply in an overlapping way. The legal overlap that follows makes Article 102 TFEU wide-ranging to the extent that legal contradictions will occur. The research concludes that the incoherence is the result of using the wrong yardstick over which to classify the cost under scrutiny.

    Based on the research results, the dissertation makes two main propositions to rectify the incoherence. First, the relevant cost benchmark ought to be the managerial forward-looking calculated out-of-pocket cost. Second, the relevant yardstick over which costs should be classified ought to be the period in which the accused dominant undertaking’s price practice is in force.

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    The Costs of Legal Certainty: A Forensically-Informed Methodology on How to Identify the Relevant Costs in Exclusionary Abuse Cases
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  • Disputation: 2023-12-08 10:00 hörsal 11, hus F, Stockholm
    Johansson, Dan
    Stockholms universitet, Humanistiska fakulteten, Historiska institutionen.
    Makt och Motstånd: Bönderna, örlogsflottan och den svenska staten 1522-16402023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The development of the Swedish state is studied through the central and local organizations that built, repaired, maintained and provisioned the Royal Swedish Navy. The state is viewed as an organization which bargained for resources with powerful social groups. Inspiration comes from theories of modern firm growth, powerholder-subordinate relations, and Charles Tilly´s theory of state formation. The statebuilding process has mainly been understood as a top-down process determined by negotiations between rulers and elites. In this dissertation, I argue for the relevance of another perspective, “statebuilding from below”. In 16th and early 17th century Sweden around 60 % of the land was owned by freeholders; freeholders who, with property rights and access to central and local representative assemblies, had influence over local political and economic issues. In the absence of a strong nobility and wealthy cities Swedish rulers, and the Swedish statebuilding process were dependent on freeholding farmers; both for their political support and the resources they represented in the form of taxes and labor. The main issue of the dissertation is to explain the different paths the organization supporting the Royal Swedish Navy took over a period of 120 years. From centralization, to decentralization, from state-organized to privately organized, and back.

    In order to demonstrate this “statebuilding from below” I investigate the organization’s provision of timber, labor and revenue, setting this in a context of power mobilization, conflicts and negotiations. Between 1523 and the mid-1540s the farmer’s met the states demand for resources to the navy with resistance, both open and violent. The state answered with coersion and repression. From the mid-1540s the state was forced to adapt to the reality of power relations between itself, the nobility and the tax-paying farmers. The result was a new way to interact and respond to farmers grievances. The system “the negotiating state” gave protection to ordinary people, against nobles, the authorities and famine, and stopped the open and violent protests. Negotiations and agreements between the king’s bailiffs and the freeholders were central for the state, and for the organizations ability to reach its goals.

    But as the navy and state power grew the system could not prevent an increased exploitation. To finance the production, shipbuilding was organized with local resources and decentralized to a vast number of local plants. In response the farmers combined the institutionally-sanctioned methods of protest with passive or hidden resistance; a resistance that grow with the states demands for revenue, ship carpenters and labor. In the first decade of the 17th century the king used the central parliament to mobilize greater resources for the armed forces and the navy.  In 1611 the decentralized organization imploded. Instead of more coercion the state was again forced to adapt to the resistance from farmers and nobles. From 1615 the organization was centralized into three large production units. The earlier system with forced labor was abandoned. Centralization and an alliance between the king and the nobles changed power relations and created stability. However, despite the stronger position of the state, the freeholders’ actions compelled the development of a system with central and local representative arenas, where negotiations could take place and complaints heard. These steps were necessary for the creation of legitimacy and the necessary compliance with continued resource extraction. The freeholders’ influence on the early modern Swedish state building process was extensive and must be described as “state building from below”.

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    Makt och Motstånd: Bönderna, örlogsflottan och den svenska staten 1522-1640
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  • Disputation: 2023-12-08 13:00 Föreläsningssalen, Stockholm
    Fossås, Ole Johnny
    Stockholms universitet, Humanistiska fakulteten, Institutionen för mediestudier.
    Extracting versatility: Films commissioned by the mining industry in postwar Sweden2023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This study investigates how films commissioned by Swedish mining companies were employed for institutional use between 1945 and 1965. A central aspect of what gave these films their versatility stems from circumstances that allowed commissioned texts to pass as non-partisan audiovisual aids, as educational and informative instruments and as occasional examples of film art through intermediaries. In detaching texts from the biases of commissioning bodies, these films were treated as instrumental – and occasionally artistically valuable – texts on mining, in relation to work management and Sápmi contexts. Because these commissioned films blended in with established institutions, rather than offering a radical voice in society, they became sources for knowledge about how and which forms of audiovisual communication on industry were regarded as broadly viable. This study contributes new knowledge on the broader environment of Swedish film, including its use by industry, its role in early public service television, and the conditions for existence of short film production in relation to subsidy policies.

    In its methodological approach, this study is in conversation with the field of useful cinema studies and seeks to expand its focus on film as part of broader organizational behaviour outside of direct company reach. Through four case studies that mix archival research with textual analysis, selected film examples are examined in how they interplayed with institutional conceptualizations of advertising, management, public service, and film as an art form. Chapter 1 contextualizes communication challenges in a nonpartisan postwar climate from the perspective of industry companies as film commissioners. Here, artistic experimentation and advertising approaches were considered unfavourable compared to a more traditional and factual approach, which was then believed to be more versatile. Chapter 2 analyses how the managerial approaches of the mining industry were revitalised, through the Swedish Council for Personnel Administration working as a film consultancy that established films about industry as an aid towards increased productivity. Through analysis of their entanglements with two films commissioned by mining companies, it is argued that the autonomy of the manager is protected, while the miner’s work is promoted as optimisable through close monitoring by management. Chapter 3 contextualises the use of industry-commissioned films on early public service television. It argues that ambiguous conceptions of public service within programming on industry presented commission films with broadcast opportunities, effectively circumventing advertising prohibitions. Analysis of two films on the mining industry broadcast in 1957 and 1960 respectively argues that television was used to impose invisibility on the existence of the industrial exploitation of Sápmi. Chapter 4 explores the relations between film policy and the dominance of commissioned films over independent short film production in postwar Sweden. Criticisms of commissioned films as boring in their adherence to traditions in filmmaking are connected to an ambition for them to become spaces for experimentation. This intention was in part driven by the lack of special subsidies for independent short film production. While some experimentation occurred in industry-commissioned films, it was sporadic in part due to commissioners not seeing themselves as patrons for the film arts.

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    Extracting versatility: Films commissioned by the mining industry in postwar Sweden
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  • Disputation: 2023-12-08 14:30 Vivi Täckholmssalen (Q211), NPQ-huset, Stockholm
    McComas, Sarah
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    The molecular basis for substrate recognition and gating in sugar transporters2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Sugar is a vital sustenance for most forms of life. For a cell to take up sugar, specialized transport proteins embedded into the membrane bilayer known as sugar porters, are required. Dysfunction of sugar porters is associated with some metabolic diseases, and their expression is upregulated in many cancers as they typically require more sugar than normal cells. Furthermore, sugar porters also play a role in the vitality of the malaria parasite.

    The mechanism of sugar transport is known as a rocker-switch alternating access mechanism. Simplistically, sugar binds between two similar domains on the outside of a sugar transporter and the domains then move around the sugar, so the sugar is exposed to the inside. During this domain movement, protein mass will block the sugar binding site from both outside and inside, forming the occluded state which is essential to ensure no substrate leakage during transport. Despite this relatively simple model of transport, little is known about how different sugar porters display diverse substrate specificity, affinity, and turnover.

    In the four papers making up this thesis, we structurally characterize missing pieces of the sugar transport cycle, identify how these states are connected with simulations, and assess factors contributing to sugar transport by functional assays. With simulations, we show how sugar catalyzes conformational change by interacting with the occluded state. We demonstrate our functional proteoliposome-based transport assay, which allows us to measure the effect of protein mutations, inhibitors, and lipid influences in sugar recognition and turnover. Characterization of the malaria parasite hexose transporter PfHT1 has allowed us to understand antimalarial inhibitor specificity against this protein which could have implications in combating the disease, as well as pharmacological control of sugar porters in general.

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    The molecular basis for substrate recognition and gating in sugar transporters
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  • Disputation: 2023-12-11 09:00 G-salen, Arrheniuslaboratorierna hus F, Stockholm
    Lundström, Oxana
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Intrinsic disorder and tandem repeats - match made in evolution: Computational studies of molecular evolution2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Proteins are both the building blocks and workers of the cell, carrying out most of the important functions. For a long time, their structure has been regarded as the primary factor for their function, but intrinsically disordered proteins demonstrate an alternative to this paradigm. Disordered proteins can temporarily assume different forms based on their interactions with other molecules and play critical roles in several biological processes, including cell signaling and regulation of gene expression.

    Tandem repeats are repeated patterns in genetic sequence. The role of tandem repeats in many protein structures is well documented today, but their role in disordered proteins is not entirely clear. This thesis aims to shed light on the mechanisms by which protein disorder and tandem repeats are linked.

    Only 2.5% of residues in all known protein sequences are characterized by the overlap of tandem repeats and protein disorder as described in Paper III, but many of these proteins have crucial functions and are linked to human diseases. Short tandem repeats emerge in this study as most frequently occurring in disordered regions. Genetic variation in disordered proteins accounts for length differences in eukaryotic genes (Paper I) and many orphan, recently evolved proteins, are disordered due to high GC content (Paper II). 

    A medical application of this research is illustrated in the thesis with examples of variations in short tandem repeats (STRs) and their role in human diseases. Paper IV presents a comprehensive resource of human STR variation and Paper V illustrates how it can be used to identify specific STRs of interest, such as in the case of colorectal cancer where variations in certain STRs lead to altered gene expression patterns in tumors.

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    Intrinsic disorder and tandem repeats - match made in evolution: Computational studies of molecular evolution
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  • Disputation: 2023-12-11 09:00 lärosal C497, hus C
    Favre, Gabriel
    Stockholms universitet, Naturvetenskapliga fakulteten, Matematiska institutionen.
    Amenable-like properties of étale groupoids2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis consists of three papers related to analytic and representation theoretic properties of étale groupoids.

    In the first paper, we characterize algebraically the type I and CCR property for ample groupoids and their non-commutative duals: Boolean inverse semigroups. Our results use and generalize Thoma’s work on discrete groups. Algebraic characterizations in the more general context of non-Hausdorff groupoids have been obtained in the author’s licentiate thesis. They use a non-Hausdorff version of the Clark-van Wyk topological characterization. We also characterize type I inverse semigroups using the Booleanization of inverse semigroups introduced by Lawson. The inverse semigroups of type I are characterized by excluding specific subquotients of their Booleanization.

    In the second paper, we show that any free action of a connected Lie group of polynomial growth on a finite dimensional locally compact space has a finite tubular dimension by constructing a tubular cover of appropriate multiplicity. As a consequence, the C*-algebras associated to the corresponding transformation groupoids all have finite nuclear dimension. The proof strategy is adapted from the strategy for R-actions of Hirshberg-Wu to the polynomial growth setting. As a corollary, we obtain that the groupoids associated to model sets in connected simply connected nilpotent Lie groups admit a classifiable C*-algebra.

    In the third paper, we study inner amenability for groupoids attached to irregular point sets in general second countable locally compact groups. Upon imposing a regularity condition on the point set–finite local complexity–we are able to show inner amenability of the corresponding ample groupoid. The motivation for this work is the question of Anantharaman-Delaroche asking whether all étale groupoids are inner amenable. As a motivating example, model sets arising from arithmetic lattices give inner amenable groupoids, even in non-amenable groups.

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    Amenable-like properties of étale groupoids
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  • Disputation: 2023-12-14 10:00 hörsal 5, Stockholm
    Lind, Petter
    Stockholms universitet, Naturvetenskapliga fakulteten, Meteorologiska institutionen (MISU).
    Kilometer-scale climate modeling of precipitation in the Nordic region2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Future changes in precipitation, in particular extremes, are among the most impact-relevant consequences of a warming climate driven by increases in atmospheric greenhouse gas concentrations. Still, climate model projections of future changes in regional and local precipitation remain uncertain. This is in part due to inabilities of climate models to properly represent important atmospheric moist processes, such as convection, as well as surface properties like complex terrain, primarily since these models are typically run at relatively coarse horizontal resolution. The application of a new generation of kilometer-scale ”convection-permitting” models (CPMs), which treat deep convection explicitly, has led to a step-change improvement in simulating precipitation, especially short-duration local intense events. Therefore, CPMs have proven to be valuable tools in understanding precipitation in present climate and its response to rising global temperatures.Here, the performance of the HARMONIE-Climate (HCLIM) CPM in a regional context has been investigated as well as the added value of this model in comparison with HCLIM run with standard grid resolution of ~10 km. In the present climate, the HCLIM CPM applied over the Nordic region outperforms both the coarser-scale HCLIM and a global reanalysis data set, especially for precipitation on sub-daily time scales in summer when precipitation is often convective. This is corroborated in a study investigating how precipitation is related to large-scale atmospheric circulation, which revealed differences between the HCLIM CPM and its coarser counterpart in convection-dominated circulation types in summer. By improving the frequency and intensity distributions, the wet bias seen in the coarser HCLIM version is reduced by the CPM while also better capturing intense precipitation events, but also improvements in the partitioning between snow and rain in complex terrain.In projections of a future warmer climate, the HCLIM CPM simulates stronger increases in heavy precipitation compared to the coarser-scale HCLIM version, most notably in the warm season, sometimes in excess of the thermodynamically constrained increase in atmospheric moisture content of ~7%/oC, referred to as the Clausius-Clapeyron scaling relation (CC-relation). Applying the HCLIM CPM over European sub-regions with different temperature and humidity conditions reveal consistently stronger increase of sub-daily precipitation at the local scale compared to the scales represented by coarser models. However, the environmental conditions played an important role in the scaling of precipitation with temperature; a scaling larger than the CC-relation was found in regions with relatively moist conditions, while in dry areas the scaling was in line with or smaller than the CC-relation.It is concluded that there is a clear benefit of using HCLIM at the convection-permitting scale, a fit-for-purpose model to investigate precipitation processes and their change following global warming over the Nordic region and elsewhere.

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  • Disputation: 2023-12-14 13:00 hörsal 11, hus F, stockholm
    Rodineliussen, Rasmus
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Socialantropologiska institutionen.
    Underwater Worlds: An Ethnography of Waste, Pollution, and Marine Life2023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    In this dissertation, I investigate relations between humans, waste, pollution, and marine life. I introduce the concept of Aquabiopolitics as a means to understand how humans govern life in water in order to enrich human life on land. The study focuses on the Baltic Sea and Lake Mälaren, using Stockholm, the capital of Sweden, as the connection point. Throughout the dissertation, I explore how human practices over time have had devastating effects on marine life and continue to have so today. 

    The dissertation engages with the marine world through underwater ethnography to provide a perspective on water from below the surface. In this endeavor, I employ the assistance of marine scientists and trash scuba divers who are jointly invested in tracking human maltreatment of water and finding solutions for treating water differently in the future. We will follow the scientists on expeditions at sea and to their laboratories in order to learn about their methods and relations to underwater worlds. Together with the trash scuba divers, we will dive into the dark murky waters around Stockholm—experiencing what it is like to move below water, among sharp and toxic waste, without any visibility.  

    The work of creating a knowing and caring relationship between humans and water is of key importance to both scientists and divers. Therefore, one of the main parts of this dissertation is to analyze how, and if, this relationship can be created: via social media, images, installations, or other means. For as the divers often say: Water is Life. Make it Important!

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    Publikationen är tillgänglig i fulltext från 2024-11-23 09:00
  • Disputation: 2023-12-15 10:00 Lärosal 22, hus 4, Albano, Stockholm
    Xiang, Yu
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Företagsekonomiska institutionen.
    Intricate Involuted Intertwinings: On Accounting, Technology, and Materiality2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The Information Age was supposed to be different. It was supposed to transform every aspect of our lives, and accounting was going to be no exception. Yet, management accounting as an academic discipline has had a fraught relationship with technology – each generation of new information technology has been written about in enthusiastic terms, only to be followed by disillusionment and abandonment some years later. It is the contention of this thesis that our current conceptualisation of the role of information technology in management accounting, where the technological and the social are understood to be two fundamentally separate and distinct entities, is inadequate in addressing the sociomaterial nature of technology, and consequently we are unable to grasp the ways in which technology is made to work in practice. New technologies in organisations do not produce change in a straightforward, predictable manner. Instead, technology and organisational processes intertwine in complex patterns, leading to the emergence of novel practices and sometimes unforeseen outcomes. 

     

    This thesis studies the mundane, material aspect of work from a sociomaterial perspective, one that emphasises the nature of technology as inseparable entanglements between the social and the material, in order to better understand the intricate, involuted intertwining between technology and management accounting. The papers that make up this thesis draw from a variety of sociological writings, including those of Knorr Cetina, Deleuze, and Galloway & Thacker, and find that technology is not solely the domain of designers and purchasers of technological systems, but is rather continuous performed by rank and file users in mundane interactions with technological artefacts. Moreover, they show that management accounting practices have material grounds, that the variety of devices we encounter in accounting, be they a chart, an ERP system, or an online ranking mechanism, do not exist in the world as disembodied and abstract concepts, but have materiality to them, and that this materiality shapes practices, often in unforeseen ways. These findings are a first step toward understanding the practical, everyday work involved in making technology work, and in turn making way for more grounded expectations of the effects of technology on management accounting.

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    Intricate Involuted Intertwinings: On Accounting, Technology, and Materiality
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  • Disputation: 2023-12-15 10:00 G-salen, Arrheniuslaboratorierna, Stockholm
    Jarnesand, Marie
    Stockholms universitet, Juridiska fakulteten, Juridiska institutionen.
    Högsta domstolen och enhetligheten: Om enhetlighetsargumentets betydelse för prejudikatprocessen2023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Argumentation of uniformity with respect to the Supreme Court has a long tradition and appears in the procedural law context in a variety of ways. It is widely used as a motive for introducing or arguing against changes in the process order, as well as an argument to justify that the Supreme Court must and should act in a certain way. Argumentation of uniformity is further used to legitimize as well as evaluate and criticize the Supreme Court’s role as precedent body. In this doctoral thesis the use and significance of uniformity argumentation regarding the Supreme Court, hereafter the uniformity argument, is examined, analysed and nuanced. A preliminary point of departure for the study is that the uniformity argument may not be as uniform as it appears at first glance. What appears to be the same argument, may in fact hide nuances, different layers or even contradictions, which can be brought to light by studying the uniformity argument more closely in the different contexts in which it is raised.

    In conclusion, I have highlighted some possible distinctions in the uniformity argument. Among other things, I have pointed to a broader uniformity argument and a narrower one. The broader uniformity argument is described as including both questions of law and questions of fact, in contrast to the narrower uniformity argument which only aims at the position with questions of law. I have highlighted a forward-looking and proactive uniformity argument and a backward-looking and reactive one. I have highlighted that the uniformity argument is used in virtually all contexts where the Supreme Court is discussed or shaped. Furthermore, I have shown how the uniformity argument is used with a variety of uses. I have put my finger on the continuity of the uniformity argument in precedent procedural contexts despite clear changes in the procedural landscape. I have identified that the vagueness of the uniformity argument is important for its resilience, but that this same vagueness can create problems. The thesis has identified, made visible and problematized that the uniformity argument contains different aspects and that different procedural institutes are based on different arguments. This becomes important for the Supreme Court as a precedent instance. 

    The hope is that the results of the thesis will contribute to increasing the rigor in discussions and reforms about the Supreme Court’s operations and focus. In a larger perspective, the study has made visible how a soluble argument such as uniformity acts as a form of meta-norm that gains importance on a variety of levels, for theory formation, legislative policy and procedural rules.

  • Disputation: 2023-12-15 10:00 hörsal 5, hus B, Stockholm
    Deliaval, Marie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of chiral allyl and propargyl boronates by organocatalytic carbene insertion to carbon-boron bonds2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis describes the development of a novel organocatalytic method for the synthesis of chiral allyl- and propargyl- organoboron compounds with high enantioselectivity. These organoboron species are versatile building blocks in asymmetric synthesis.

    We have developed a new efficient homologation method of alkenyl boronic acids. This reaction affords enantiomerically enriched trifluoromethylated allylboronates. These organoboron species were used in allylboration of carbonyl compounds, imines and indole derivatives. The reactions proceeded with a remarkably high stereoselectivity to give homoallylic alcohols and amines. In addition, the chiral allylboronic acids can be oxidized to the corresponding alcohols with retention of the configuration.

    Based on the homologation of alkenylboronic acids a new three-component reaction is developed. This reaction involved coupling of alkynyl boronates, diazo compounds and ketones in the presence of chiral organocatalysts. This coupling proceeds with high selectivity under mild reaction conditions. The three-component coupling reaction is based on a homologation–allylboration sequence. The process is suitable for synthesis of CF3- and TMS-substituted allenols with excellent diastereo- and enantioselectivity. Application of aromatic, cyclic and non-cyclic ketones leads to formation of chiral tertiary allenols.

    We have also studied the effects of boronic acid esters on the outcome of the homologation reaction. It was found that a facile transesterification of the boronate precursors with the organocatalyst, BINOL derivatives, is a prerequisite of the successful homologation reaction.

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    Synthesis of chiral allyl and propargyl boronates by organocatalytic carbene insertion to carbon-boron bonds
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  • Disputation: 2023-12-15 13:00 De Geersalen, Geovetenskapens hus, Stockholm
    Pereira Freitas, Gabriel
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Bioaerosols and their importance for low-level Arctic clouds2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Bioaerosols are microorganisms or functional parts of them or other biological matter suspended in air. Examples are bacteria, viruses, pollen, spores, or smaller plant debris. In the atmosphere, bioaerosols can play various functional roles, such as facilitating the spread of genetic material. Moreover, they can play an important role in climate by serving as ice nucleating particles and thus participating in cloud formation. Bioaerosols might play a significant role in a changing Arctic, where aerosol concentrations can be very low, and where natural as well as anthropogenic aerosol sources are subject to drastic changes due to climate change. In the Arctic, aerosols and clouds are prominent actors in climate by mediating short- and long-wave radiation interactions, which are further complicated by the presence of high-albedo surfaces such as sea ice. Thus, constraining the sources of aerosols and their interaction with clouds is key to understanding the Arctic climate and the changes it has been and will undergo.

    In this work, we used a single-particle instrument to differentiate bioaerosols from other particles on the basis of their fluorescence and light-scattering signal. In the Baltic Sea, we found that bioaerosols are at least 1 in every 104 coarse particles emitted by sea spray. Their temporal emission pattern was not directly correlated with biological tracers, such as chlorophyll; instead, their emission was modulated by the transition between different water masses.

    The same technique was then applied to a one-year measurement campaign at an Arctic mountain top observatory as part of a greater aerosol-cloud interaction campaign. The recorded seasonal cycle of bioaerosol concentrations peaked in summer and was most likely related to regional terrestrial sources, as its appearance coincided with a decrease in snow cover and an increase in vegetation activity. Moreover, bioaerosols were found to drive the concentration of high-temperature ice nucleating particles, even in winter. In the third study, the importance of bioaerosols serving as cloud seeds was investigated by directly measuring the concentration of bioaerosols within cloud residuals.

    The presented findings help to elucidate the contribution of bioaerosols to coarse-mode particles for marine and Arctic environments, while also providing a direct link between bioaerosols and clouds. Furthermore, we also provide the first direct observations of bioaerosols involved in cloud formation in the Arctic, along with their possible contribution to the prevalence of mixed-phase clouds in the beginning and end of summer. Thus, these results contribute to a better understanding of atmospheric (bio-)aerosol-cloud-interactions processes in the vulnerable Arctic environment but are also valuable for further developments of Earth system models that include ice nucleating and/or bioaerosol particles.

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    Bioaerosols and their importance for low-level Arctic clouds
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  • Disputation: 2023-12-15 13:00 hörsal 9, hus D, Stockholm
    de Ron, Anette
    Stockholms universitet, Humanistiska fakulteten, Institutionen för ämnesdidaktik.
    Problemlösning i matematikdidaktik och lärarutbildning: Ett mångdisciplinärt utforskande och affirmativ kritik2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The aim of this thesis in mathematics education is to produce knowledge about problem-solving as a broad and complex phenomenon in mathematics teacher education, historically and in the present. With a multidisciplinary approach and affirmative critique, possible new understandings of the phenomenon are investigated, extended and transformed in three sub-studies and two chapters in the wrapping. The thesis builds on previous research on teacher education but seeks to contribute to a multidimensional understanding of the phenomenon of problem-solving. The first sub-study provides a configurative research review that offers a picture of the different relationships in which problem-solving is involved, and how different aspects of problem-solving are highlighted and become complementary. The second sub-study is a discourse analysis of historical texts on problem-solving where the data consists of texts written for and by teachers from the 1840s and onwards. The sub-study shows how discursive truths about problem-solving are formed and consolidated over time. The third sub-study brings attention to the materiality of problem-solving teaching, and highlights how mathematics teaching in secondary school, in the form of classroom observations, can be understood in a new materialist perspective. In addition, the thesis includes further analysis of problem-solving – presented in two chapters in the wrapping – and as a consequence the thesis may is designed as a hybrid between a compilation thesis and a monograph. In one of the chapters, previous research is traced diffractively with regard to the arguments put forward as to why problem-solving is important. In the other chapter, the results of the three sub-studies are read diffractively, through and with feminist new materialism. The thesis spans over several theoretical-methodological fields and takes the reader on a walk through the problem-solving landscape. The overall results show that problem-solving is a composed phenomenon that appears in different ways in different theoretical perspectives and methodological starting points, as well as in different times and spaces. To summarize, the thesis shows that 1) there is a need for teacher education to encourage pre-service teachers to acknowledge the multiplicity regarding both knowledge of problem-solving and the solving of problems, 2) teaching in teacher education can make visible, but also question, dualities such as thinking–acting, body–soul, rationality–emotions, woman–male in order to find other ways of understanding problem-solving, 3) when aspects of gender, inequality and other sociopolitical issues are addressed in mathematics education content in teacher education, problem-solving can be linked even more to a societal context, 4) the consideration and handling of emotions in relation to mathematics is significant as a knowledge in itself and contributes to a more composed understanding of problem-solving, and 5) new dimensions of problem-solving can emerge when the planning of mathematics teaching is based on a relational understanding of learning and supported by new materialist theory. The thesis contributes with new ways of thinking about problem-solving as a composed phenomenon, what it can entail and become, and provides suggestions for an expanded and 'respons-able' understanding of problem-solving that can contribute to further develop mathematics education in teacher education.

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    fulltext
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  • Disputation: 2023-12-15 13:00 sal 2403, Institutionen för pedagogik och didaktik, Stockholm
    Eslahchi, Morteza
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för pedagogik och didaktik.
    Learning Together, Leading Change: Understanding Collective Learning in Social Entrepreneurial Organisations2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Denna avhandling syftar till att skapa en förståelse för kollektivt lärande i sociala entreprenörsorganisationer i Sverige, med särskilt fokus på COVID-19-pandemin. Genom att använda ett perspektiv centrerat kring kollektivt lärande, avser jag att utforska följande nyckelområden: a) de lärande villkor och processer som krävs för att bli en social entreprenör och skapa en social entreprenörsorganisation, b) kollektivt lärandes betydelse för organisatorisk anpassning och förändring när man hanterar exogena faktorer som COVID-19-pandemin, och c) ledarskapets roll i att skapa förutsättningar som är gynnsamma för kollektiva lärandeprocesser i sociala entreprenörsorganisationer under COVID-19-pandemin.

    Baserat på empiriska studier omdefinierar denna forskning ledarskap som en stärkande, samarbetsinriktad praxis som är nära sammankopplad med dynamiken i kollektivt lärande. Studien granskar också de adaptiva och evolutionära aspekterna av organisatoriska processer och betonar deras centrala roll för kollektivt lärande. Vidare belyser den effektiviteten i en ansats centrerad kring kollektivt lärande för att driva meningsfull organisatorisk förändring, i kontrast till toppstyrda strategier. Utförd under den globala omvälvningen som COVID-19-pandemin orsakat, erbjuder denna forskning en unik möjlighet att undersöka kollektivt lärande som ett verktyg för motståndskraft i turbulenta tider. Denna studie fyller en lucka i den befintliga litteraturen genom att fokusera på den svenska kontexten och erbjuder insikter för forskare, praktiker och beslutsfattare inom socialt entreprenörskap. Slutligen understryker forskningen potentialen hos kollektivt lärande att utrusta sociala entreprenörsorganisationer för hållbar innovation och motståndskraft, särskilt under samhälleligt utmanande förhållanden.

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    Learning Together, Leading Change: Understanding Collective Learning in Social Entrepreneurial Organisations
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  • Disputation: 2023-12-15 15:00 sal G, Arrheniuslaboratorierna, Stockholm
    Nilsson, Josefin
    Stockholms universitet, Humanistiska fakulteten, Institutionen för ämnesdidaktik.
    Vi ser om dom flyter typ.” : Att utveckla en språk- och kunskapsutvecklande ämnesundervisning för nyanlända elever – möjligheter och begränsningar ur lärarperspektiv.2023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    For more than a decade, extensive government-funded school improvement programs have aimed at strengthening quality and equality in Swedish schools. Since 2015, a specific focus has been on the group of newly arrived migrant students in terms of in-service training for teachers. Research about such initiatives is, however, lacking, particularly regarding how these efforts help teachers to better attend to newly arrived students’ language and content learning in various school subjects. The overall aim of the present thesis is to contribute new and in-depth knowledge about subject teachers’ possibilities for developing a language and content integrated approach in their subject teaching for newly arrived migrant students at secondary school level (students aged 13–16). The study was conducted in a school in tandem with an in-service training on language and content integrated teaching and learning from a second language and multilingual perspective. Using a linguistic ethnographic approach, two secondary school teachers’ meta-reflections and teaching practice in Science and Mathematics are in focus. The rich material produced over two school years during and after the in-service training consists of audio-recorded interviews, the teachers’ collegial meetings during the in-service training, audio-and video-recordings from classroom observations, fieldnotes, and photos. Using an ecological and critical framework, the teachers’ perspectives are related to the material and structural context. Central to the analyses is the teachers’ situated didactic agency and how it is shaped by power relations, available resources, and circulating discourses. These analyses are supported by the interconnected model of teacher professional growth (Clarke & Hollingsworth, 2002), which is expanded via the use of didactic agency. Findings show that the school’s mainstream policy, combined with a lack of adequate resources, limits the teachers’ opportunities to fully make use of in-service affordances and, in the long term, their possibilities for practice development. The findings also make visible how intertwined and colliding discourses about teaching in general, and newly arrived students in particular, impact on the teachers’ actions and investments. This does not only affect what the teachers can do, but also what they can learn and develop further in their teaching practices. This thesis argues that what teachers do – and do not do – needs to be understood in relation to their didactic agency. Consequently, the present thesis problematizes school-improvement initiatives where professional development for teachers is constructed as a taken-for-granted solution to complex structural problems. The thesis further argues that in-service training for teachers cannot be regarded as a substitute for the lack of material resources and spaces for manoeuvre. These findings are relevant for future school-improvement initiatives as well as professional development initiatives, especially regarding marginalized student groups. In the thesis, research conducted in collaboration with professionals in schools is encouraged, where conditions and possibilities for teachers to design teaching practices that support linguistically minority students could be further explored. In such studies, teachers’ didactic agency would serve well as a central analytical concept.

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    ”Vi ser om dom flyter typ.” : Att utveckla en språk- och kunskapsutvecklande ämnesundervisning för nyanlända elever – möjligheter och begränsningar ur lärarperspektiv.
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  • Disputation: 2023-12-18 10:00 Vivi Täckholmssalen (Q211), Stockholm
    Gaudry, Michael James
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut.
    Comparative analysis of the thermogenic protein UCP1 across the mammalian phylogeny2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Uncoupling protein 1 (UCP1) drives mitochondrial inefficiency to produce heat in mammalian brown adipose tissue (BAT). Many mammalian species rely on this form of adaptive non-shivering thermogenesis (NST) to defend high body temperatures in the cold. Little is known regarding how evolution may have shaped UCP1 function to reflect distinct thermoregulatory requirements of various lineages. This thesis merges genetic and functional data while using a comparative approach to gain insights into the evolutionary rise of thermogenic UCP1, as well as its repeated loss of function among several eutherian lineages. UCP1 structure-function relationships and mechanistic insights are gained by examining natural mutations among the orthologues of different species.  

    In Paper I, we reveal that, like eutherian mammals, marsupial UCP1 is expressed in adipose tissue of developing young gray short-tailed opossums (Monodelphis domestica) and coincides with the onset of thermoregulatory competence. Transcriptomic analyses reveal partial browning signatures in adipose tissue of young opossums, resembling eutherian beige adipose tissue. Overexpression of marsupial UCP1 in a mammalian test system (HEK293 cells), however, reveals its lack of thermogenic functionality. I then performed ancestral reconstruction of UCP1 and demonstrate that the thermogenic function arose in the stem eutherian ancestor. 

    In Paper II, I uncover that UCP1 not only became pseudogenized in pigs (e.g. Sus spp.), but in a common ancestor of both pigs and peccaries (e.g. Catagonus wagneri) as indicated from a shared inactivating mutation, re-calibrating the timeline of this inactivation and our understanding of how it may limit the geographic distribution of modern peccaries. 

    In Paper III, I uncover a novel UCP1 pseudogene unique to the largest seals, elephant seals (Mirounga spp.), showing that UCP1 is retained within most members of the seal lineage for neonatal defense of body temperatures, but its loss coincides with the extreme body sizes attained by elephant seals. 

    In Paper IV, we functionally verify that N-terminal truncation or frameshift mutation repair cannot rescue the thermogenic function of elephant seal UCP1. By contrast, we verify the thermogenic capacity of UCP1 of the small-bodied harbor seal (Phoca vitulina), matching that of terrestrial eutherians.

    In Paper V, we examine UCP1 in the naked mole-rat (Heterocephalus glaber), a species that displays a natural mutation to the histidine pair motif that has been previously deemed crucial for UCP1 function. We hypothesized that this may underlie the poor thermoregulatory abilities of the species. Our assessment of UCP1 mutants, however, reveal that the naked mole-rat retains UCP1 function and that the histidine pair motif is unnecessary for the GDP-sensitive thermogenic function of the protein, providing important structure-function information of UCP1 and questioning a proposed mechanistic model. 

    In summary, this thesis utilizes UCP1 as a biomarker to trace the evolution of mammalian NST and thermoregulation. Insights gained provide clues to the various factors influencing mammalian endothermy and hints of structure-function relationships in this thermogenic protein.  

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    Comparative analysis of the thermogenic protein UCP1 across the mammalian phylogeny
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  • Disputation: 2023-12-18 10:00 De Geersalen, Geovetenskapens hus, Stockholm
    Maneas, Georgios
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Towards co-management of Gialova Lagoon: A Natura 2000 coastal wetland in Messinia, Greece2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The management of Natura 2000 sites is considered as the cornerstone for the conservation and restoration of biodiversity within Europe. However, protected ecosystems provide a plethora of benefits to local societies, and support the local economy. Thus, to seek solutions for complex environmental issues within Natura 2000 sties it is imperative to approach the site of concern as a connected social-ecological system, and to strengthen the participation of stakeholders in decision-making following a co-management approach.

    Gialova Lagoon wetland, in Messinia, Greece represents an example of Natura 2000 site which needs to be managed. The overall aim of the PhD thesis was to assess the problem of lagoon salinization, and provide policy recommendations for wetland restoration and management of associated freshwater resources under a changing climate. The thesis has followed a social-ecological approach, by integrating DPSIR framework with participatory Systems Dynamic modelling and the concept of ecosystem services. Knowledge gaps about major social and ecological components were assessed by applying a variety of methods, namely (a) field monitoring and observations, (b) GIS analyses, (c) consultation with stakeholders, (d) modelling and scenarios.

    The thesis results suggested that past human interventions had multi-fold effects on the Gialova Lagoon wetland, namely hydrology alteration, ecosystem fragmentation, loss and transformation of natural habitats. Furthermore, the combined effects of alterations in hydrology and climate change have led to increased salinity in the wetland over time. These alterations had profound implications on wetland ecosystem services such as the diversity of habitats and waterbirds and the provision of fish. Under contemporary hydrological connectivity and on-going climatic conditions, the mean annual salinity of the lagoon has increased from approximately 35 g/L during the period 2016-2018 to approximately 40 g/L during the period 2021-2023 indicating a salinization increase of approximately 1 g/L per year. 

    To identify restoration alternatives, the work under the PhD thesis has engaged scientists with local stakeholders from the sectors of agriculture, fishing, tourism, and public administration, in a co-management approach. The end product, an SDM (Systems-Dynamics model) co-created with stakeholders, was suitable for exploring scenarios for salinity regulation and management of associated freshwater resources, under a changing climate (RCP 4.5). The derived management suggestions, namely restoration of the connectivity with the surrounding freshwater bodies (river, artesian springs) and between habitats (e.g., lagoon-marshes), could result in the de-salinization of the lagoon within a 10-year period, and could be applied within the Natura 2000 framework as they consider social and ecological needs (e.g. enhancement of biodiversity and fish production). However, under current abstraction rates for irrigation and municipal water-supply, there is a high risk of groundwater scarcity during years with dry conditions, and thus investments in water-saving technologies (e.g. smart irrigation) should be promoted to ensure adequate water availability for restoration, and enhanced resilience of the local economy against groundwater scarcity.

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    Towards co-management of Gialova Lagoon: A Natura 2000 coastal wetland in Messinia, Greece
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  • Disputation: 2023-12-18 10:00 sal FB52, AlbaNova universitetscentrum, Stockholm
    Pognan, Quentin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för astronomi.
    Non-Local Thermodynamic Equilibrium Spectral Modelling of Kilonovae2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The astrophysical origin of rapid neutron capture (r-process) elements has long remained a puzzle and been the object of scientific debate. Neutron star (NS) mergers have historically been suggested as an ideal site for the creation of these elements, and were propelled into focus following the detection of the first binary neutron star (BNS) merger in 2017. The gravitational wave (GW) signal GW170817 was accompanied by a short gamma-ray burst (sGRB) GRB170817A, and a radioactively powered electromagnetic (EM) transient AT2017gfo, known as a kilonova (KN). Since this detection, the study of NS mergers has greatly expanded across the diverse fields that model the various stages of the merger, from GW signal modelling, to radiative transfer studies predicting the emergent KN lightcurves (LCs) and spectra.

    One main goal of studying NS mergers and the associated KNe is to establish the importance of compact object mergers as key sites of r-process nucleosynthesis in the Universe. As such, identification of elements and their abundances within the merger ejecta represents a critical objective. LC and spectral analyses of KNe provide promising channels to do so, and require detailed models in order to interpret observational data. With complete GW and multi-band EM data only available for a single object thus far, the importance of detailed models regarding every aspect of KN physics is paramount. KN simulations typically make use of radiative transfer (RT) codes that propagate photons through the expanding ejecta, in order to provide LC and spectral outputs. These often model the early, photospheric times of the KN, when the ejecta are still dense enough such that the gas state is well described by Local Thermodynamic Equilibrium (LTE) conditions, which requires thermal collisional processes to dominate within the ejecta.

    Since the ejecta are expanding rapidly however, these conditions cease to apply after several days, and the KN transitions to the Non-Local Thermodynamic Equilibrium (NLTE) regime, where thermal collisional processes are no longer dominant in establishing the gas state of the ejecta. This now requires the detailed modelling of various NLTE processes which increases the complexity, yet modelling of this regime can also provide great rewards. Notably, as times goes on and the ejecta continue to expand, they will eventually become optically thin to most wavelengths and enter the nebular phase. There, the spectra are expected to be emission line dominated, providing an excellent opportunity for element identification by spectral analysis.

    This doctoral thesis conducts RT modelling in order to explore the NLTE regime of the KN in a systematic, physically accurate way. To this end, the spectral synthesis code SUMO (SUpernova MOnte Carlo Code) was adapted to model KNe, and used to investigate the spectral emission in the NLTE regime. The work in this doctoral thesis provides a first step into fully consistent modelling and analysis of KNe at later times, and a solid foundation from which to move forwards.

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    Non-Local Thermodynamic Equilibrium Spectral Modelling of Kilonovae
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  • Disputation: 2023-12-19 13:00 De Geersalen, Geovetenskapens hus, Stockholm
    Vryonidis, Efstathios
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Method for measurement of exposure to electrophiles: Strategy for identification and exposure estimation using N-terminal haemoglobin adducts2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    We are exposed to many chemicals in our everyday life. Some of these chemicals could pose risks for our health. To reduce such risks, it is important to know what we are exposed to, how much, and how toxic the chemicals are.

    This thesis focuses on development and novel applications of a method for identifying and quantifying adducts as biomarkers of exposure to electrophiles. Electrophiles are reactive and can be measured as their stable reaction products (adducts) with haemoglobin (Hb) using the FIRE procedure™. This method utilizes Fluorescein Isothiocyanate to selectively cleave the adducted (R) N-terminal valine in human Hb, with a modified Edman procedure.

    The primary aim was to further develop the FIRE procedure for application to a larger number of human blood samples, and to decrease the amount of sample needed. To achieve this, the method was adapted to 96-well plates. Further improvements resulted in a method that uses ca. half of the material used in the original method and can be used to analyse 1000 samples in one to two months.

    The newly developed version of the FIRE procedure was applied to analyse blood from 144 Norwegian adults (Paper I) and 600 Swedish adolescents (Paper II), to estimate exposure to the electrophile acrylamide. IARC has classified acrylamide as a probable human carcinogen. Diet is a major source of exposure to acrylamide in the general population, as it is formed in carbohydrate-rich food during high temperature processing. Acrylamide intake was calculated from Hb adduct levels and compared with intake estimates calculated from self-reported food consumption data obtained from dietary records and food frequency questionnaires, combined with data for acrylamide content in food. In the Norwegian study, acrylamide intake was estimated by probabilistic calculations of the two types of food consumption data, which resulted in that no large difference in the median estimate obtained by these methods was observed in comparison of estimated daily intake from Hb adduct data (0.24-0.30 µg/kg body weight). In both studies (Papers I, II), the calculated margin of exposure with regard to risk for cancer indicates that acrylamide intake from food is of concern in the studied populations.

    In Paper III, an unknown adduct, observed in earlier FIRE adductomics work, was identified with the help of high resolution accurate mass spectrometry, a synthesized standard, and nuclear magnetic resonance spectroscopy. A strategy to trace the source of the adduct was evaluated, and the epoxide glycidic acid was confirmed as a possible precursor, by measurement of adduct formation rate in vitro in human blood.

    Finally, in Paper IV the FIRE procedure was compared to bottom-up proteomics to study Hb adducts from acrylamide, acrylic acid, glycidic acid, 2,3-epoxypropyl phenyl ether, 2-methyleneglutaronitrile, and 1-chloro-2,4-dinitrobenzene (DNCB). Adducts from all electrophiles were identified with bottom-up proteomics, with Cys93 in the beta chain of Hb as the most reactive side chain. The FIRE procedure was inefficient to detect bulkier/electron-withdrawing adducts, as from the contact allergen DNCB.

    In conclusion, FIRE has high detectability for Hb adducts, although it is not suitable for adducts from all electrophiles. It is a valuable tool to identify and measure adducts, and to estimate exposure/intake of electrophiles. The new version of FIRE would facilitate the application for exposure measurement in epidemiological studies.

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    Method for measurement of exposure to electrophiles: Strategy for identification and exposure estimation using N-terminal haemoglobin adducts
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  • Disputation: 2024-01-12 13:00 sal 2403, Institutionen för pedagogik och didaktik, Stockholm
    Blåvarg, Ebba Christina
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för pedagogik och didaktik.
    Psykologi på schemat: Formeringen av ett skolämne, 1960–20152023Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The school subject psychology in Sweden has undergone several extensive transformations during the period 1960–2015. Since the launch of Läroplan för gymnasiet 1965, psychology is a part of the national curriculum for upper secondary level as a standalone school subject in Sweden. However, it has been formulated differently within different discursive practices. 

    This thesis focuses on the formation of the school subject psychology by analyzing texts on the subject from mainly three different practices where the subject is constructed. The first is a bureaucratic space that includes public policy texts developed through cooperation and regulation by way of bureaucratic processes. The second is a practice-oriented space and it includes teaching materials such as textbooks produced by publishers and individual authors. The third practice is a professional space and includes the discourse on the school subject psychology among teachers in the subject teacher’s association, teacher magazines and debate articles. Through a discursive perspective, the source material from these practices have been analyzed both by focusing on each space separately, and in parallel. 

    Overall, the discourse on the school subject psychology has changed dynamically during the focused period, in the different spaces, which is depicted in detail with examples and excerpts. In addition, four overarching discourse orders are presented. First, the overarching empirical and scientific stance that permeated the subject at the beginning of the national curriculum in the 1960s. Later, in the 1990s and 2000s, an inward shift in subject focus, from being useful for understanding the world with a critical view, to critically examining and evaluating various psychological theories. However, perhaps the most unexpected finding are two major orders of discourse that can be seen in between these in time. Firstly, an overall vivid activity in all the practices and the major change that the subject underwent in the 1970s, in conjunction with the subject revision in 1979. And secondly, the extensive and almost absolute silence that followed in relation to the subject psychology. 

    This thesis contributes to the research field by mapping the formation of psychology as a school subject in Sweden through different discursive practices, as well as highlighting various orders of discourse in relation to psychology as a school subject. 

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    Psykologi på schemat
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