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  • Public defence: 2023-09-25 14:00 Air & Fire, Solna
    Zhu, Wensi
    Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics.
    Decipher protein complex structures from sequence2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Proteins are essential constituents of biological systems. A profound understanding of protein structure is significant for unraveling the intricate mechanisms of biological processes. The recent development of computational methods using AI technology is revolutionizing the structural biology field. Accurate predictions of three-dimentional protein structures can be generated from protein sequences, enabling rapid and accurate insights into protein interactions and functions. This thesis aims to investigate the applications of various cutting-edge methods in protein complex structure prediction. We first explore using trRosetta for dimeric protein complexes, and the study shows that the single-chain protein structure predictor is feasible for protein complexes. In light of the success of AlphaFold2, we use the pipeline FoldDock, which is an adaption of AlphaFold2 on protein complexes, for protein-protein interactions (PPIs) of two human interactome datasets and construct a PPI network. Next, we conduct a benchmark study of AlphaFold-Multimer in multi-chain protein complexes with 2 to 6 chains and examine how different evaluation scores affect the prediction assessment. In the last paper, we predict the large protein complexes starting from subcomponents using AlphaFold2 and a Monte Carlo Tree Search algorithm. The studies in this thesis show that deep learning approaches can yield reliable results in predicting protein complex structures, and there is ample potential for further improvement. 

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  • Public defence: 2023-09-28 13:00 De Geersalen, Geovetenskapens hus, Stockholm
    Åhlén, Imenne
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Ecosystem services of wetlands and wetlandscapes under hydro-climatic change: Impacts of water flow and inundation patterns2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Wetlands provide ecosystem services valuable for human society and are therefore often considered as nature based solution to different environmental problems. However, with centuries of wetland degradation due to anthropogenic pressures, such as agricultural expansion and forest industry, as well as pressures from climate change, there are large challenges for sustainable wetland management. Thus, for wetland protection and restoration practices to be successful, a deepened understanding on the actual mechanisms controlling wetland functions is required. Understanding how wetlands are connected, with and influenced, by their surrounding environment is also needed. Although most pressures experienced by wetlands operate on scales beyond the individual wetland scale, relatively few studies have thus far addressed large-scale functions and ecosystem service provision from hydrologically interconnected wetlands at the scale of wetlandscapes (i.e., the wetlands’ aggregated hydrological catchments in the landscape). The aim of this thesis is to investigate ecosystem service delivery from wetlands and wetlandscapes under hydro-climatic changes, considering 25 different wetlandscapes located in four different climate zones of the world. The thesis also systematically quantifies ecohydrological characteristics important for ecosystem service delivery and biodiversity support of wetlands and wetlandscapes in the Norrström Drainage basin located near Stockholm, Sweden. 

    Conducted hydro-climatic analyses showed that impacts of climate change on wetlandscapes cannot be fully understood from average changes in climatic variables of the climate zones within which the wetlandscapes are located. This may be due to the fact that wetlands are not randomly and evenly distributed within climate zones, but may be located in areas subject to stronger climatic changes than regional means. In addition, anthropogenic pressures were on average shown to have higher impacts on runoff in wetlandscapes in comparison to climate change. The pressures however showed relatively large variability between different wetlandscapes, which needs to be considered in mitigation strategies against wetland degradation and deterioration. Similarly, regarding wetlandscape ecohydrological characteristics, results indicated that there are variability between wetlandscapes of different sizes, where larger wetlandscapes showed features that can support ecosystem services to larger degree than small wetlandscapes. Large spatial variability in wetland ecohydrological characteristics was also seen within a wetlandscape. For instance, water storage dynamics and buffering capacity varied depending on the position of the wetland in the landscape. These differences in hydrological conditions were shown to result in different inundation dynamics between wetlands, which for instance also showed to impact insect community composition.

    Overall, this thesis shows that assessments of wetland ecosystem services need to be addressed using a wetlandscape approach, combined with actual on site hydrological measurements. The approach used in this thesis could help decrease uncertainties related to the impacts of hydro-climatic changes and anthropogenic pressures on wetlands and wetlandscapes, supporting location-specific wetland management strategies related to creation, restoration and sustainable use of wetlands and their ecosystems.

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  • Public defence: 2023-09-28 13:00 lärosal 7, hus 1, Albano, Stockholm
    Wandery, Oscar
    Stockholm University, Faculty of Social Sciences, Stockholm Business School.
    The Ecstasy of Tragedy: An Ethnography of Hospice2023Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Culture is a double-edged sword in organizational research. Certain researchers consider culture the key to understanding organizations while others see it as a pseudo-scientific and faddish term. Similarly in the private sector, some argue that it is an essential part of their company’s success while others treat it as a high-scoring word in corporate-speak-bingo. This dissertation lies somewhere in between these positions. This dissertation explores the organizational culture of hospice care based on three years of volunteering (bi-weekly), two months of non-participant observations, and 30 interviews (17 semi-structured and 13 unstructured). It makes the case that while some organizations are not subject to distinct or persistent cultures in an anthropological sense, other organizations display cultural continuity in ways that resemble clans, tribes, or communes. The purpose of this dissertation is to explore the cultural reproduction of such an organization – hospice. Building on work within affective theory and new-wave organization culture, this dissertation discusses the role that ecstasy plays in the persistence of communal bonds in hospice, and it explores different social- and psychological processes within hospice that leads to the maintenance of its norms, symbols, and values. 

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  • Public defence: 2023-09-29 08:15 hörsal 1, hus 1, Albano, Stockholm
    Mechler, Jakob
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Beyond the Blank Screen: Internet-Delivered Psychodynamic Therapy for Adolescent Depression: Evaluating Non-Inferiority, the Role of Emotion Regulation, and Sudden Gains2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Adolescent major depressive disorder (MDD) is a common and debilitating disorder, associated with clinically significant distress and impairment in functioning. A vast array of negative consequences of adolescent MDD have also been found to extend into adulthood. Still, the majority of affected youths do not receive adequate treatment. Internet-delivered interventions address many barriers to treatment, for instance stigma and lack of qualified psychiatric care. However, the most studied internet-delivered treatment, internet-delivered cognitive behavioural therapy (ICBT), leads to clinically meaningful change in somewhat less than 50% of participants. These results indicate the need for treatment alternatives. This thesis consists of three empirical studies examining a newly developed such alternative, internet-delivered psychodynamic treatment (IPDT). Study 1 (n = 272) was a randomised controlled trial, testing whether IPDT was non-inferior to ICBT for depressed adolescents (15–19 years). Results indicated that both treatments were effective, with large within-group effects, and that IPDT was non-inferior to ICBT. No significant differences were noted on primary or secondary outcomes in the intent-to-treat analyses. Study 2 (n = 67) tested emotion regulation as a baseline predictor of rate of change, and whether intra-individual change in emotion regulation was a mechanism of change in IPDT. Results indicated that patients with relatively more severe deficits in emotion regulation had a steeper trajectory towards improvement. Intra-individual changes in emotion regulation also predicted improvements in the subsequent week, indicating that emotion regulation acted as a mechanism of change in IPDT. Study 3 (n = 66) tested whether sudden gains (SGs) and large intersession improvements (LIIs; defined as SGs without demanding symptom stability pre- and post-gain) were associated with superior outcome. LIIs were associated with improved outcome at post-treatment and at follow-up, whilst SGs were not. Overall, the above findings suggest that IPDT is a viable alternative to ICBT for depressed adolescents, that IPDT partly works through increases in emotion regulation and that patients who improve suddenly, between consecutive weeks in IPDT, are more likely to benefit from treatment.

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    Beyond the Blank Screen: Internet-Delivered Psychodynamic Therapy for Adolescent Depression: Evaluating Non-Inferiority, the Role of Emotion Regulation, and Sudden Gains
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  • Public defence: 2023-09-29 13:00 Vivi Täckholmsalen (Q-salen), NPQ-huset, Stockholm
    Rêgo, Alexandre
    Stockholm University, Faculty of Science, Department of Zoology.
    Quo vadis? Insights into the determinants of evolutionary dynamics2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Predicting future evolutionary outcomes and explaining past and current patterns of biodiversity are fundamental goals in evolutionary biology. Trajectories of evolving populations are determined by evolutionary mechanisms (natural selection, mutation, genetic drift, and gene flow) and the environment in which the populations are found. Our ability to predict and explain evolution are thus dependent on understanding how, and when, these mechanisms and the environment affect evolutionary outcomes. However, many nuances exist in the interactions of these mechanisms with each other. Furthermore, environments can be incredibly complex– too complex to capture fully when designing controlled experiments to test evolutionary hypotheses. It is clear that several challenges exist in composing a comprehensive synthesis of the determinants of evolution.

    In this thesis, I have contributed to our understanding of evolutionary dynamics and outcomes by exploring how the above-stated factors affect inferences and predictions of evolution. I leveraged both computational and biological systems to answer several evolutionary questions. I first used simulations to estimate the effects fluctuating population size had on deterministic trajectories of adaptive alleles (Paper I). I found that declines in population size can alter the rate at which adaptive sweeps occur. As a consequence of altered rates of sweeps, our ability to infer accurate strengths of selection is decreased, even when selection is very strong. In a second experiment (Paper II), I used the seed beetle Callosobruchus maculatus to investigate (1) whether environments which imposed stronger selection would result in higher phenotypic and genomic parallelism, and (2) whether the degree of parallelism was dependent on the evolutionary history of populations. Despite expectations that adaptation to the environment which imposed stronger selection would result in higher parallelism, the opposite results were observed. However, the degree of parallelism within treatments varied considerably among populations of different evolutionary histories. In a final experiment (Paper III), I explored how environmental complexity alters the dynamics and outcomes of evolution using populations of the yeast Saccharomyces cerevisiae evolved in a full-factorial combination of several environments. I found that trade-off evolution was prevalent in complex environments, and the dynamics of evolution were dependent on the level of environmental complexity and the inclusion of specific stressors. Finally, I used the same evolved populations of yeast to ask whether the outcomes of evolution in highly complex environments could be predicted based on outcomes in populations evolved to the individual components of the complex environment (Paper IV). Across all biological levels, there existed very little predictability from evolution to the individual environmental components.

    The conclusions of this thesis align with the outcomes of numerous prior investigations into the predictability of evolution– it depends on context. However, this thesis highlights the importance of often-overlooked elements such as: (1) the capacity of demography to alter predictable trajectories of selected alleles, (2) the impact of evolutionary histories on the identification of parallelism in replicated populations, and (3) the potential omission of key ecological factors essential for adequately describing evolution in nature.

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  • Public defence: 2023-09-29 13:45 hörsal 6, hus 4, Albano, Stockholm
    Lindqvist, Karin
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Making Connections: Outcomes and the Role of the Therapeutic Relationship in Internet-Delivered Psychodynamic Treatment for Adolescent Depression2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Major depressive disorder (MDD) is ranked one of the most burdensome disorders for adolescents worldwide. There is an urgent need for accessible interventions, as many adolescents suffering from MDD do not receive treatment. Internet-delivered interventions remove barriers to seeking and receiving treatment, and internet-delivered cognitive behavioural therapy (ICBT) has been found to be effective for adolescent MDD. However, not all are helped by ICBT and treatment alternatives are needed. Internet-delivered psychodynamic therapy (IPDT) has previously been tested with promising effects in adults, but no studies have assessed its efficacy for adolescents. Furthermore, little is known about mechanisms of change in internet interventions targeting adolescent MDD and how adolescents experience the therapeutic relationship in IPDT. This thesis aims to evaluate efficacy as well as processes and experiences of IPDT, from different perspectives.

    Study I investigated effects of IPDT for adolescents aged 15–18 (n = 76) suffering from MDD, compared to control condition. IPDT was found to be significantly more effective than a supportive control condition on reducing depression (d = 0.82). Furthermore, moderate to large significant effects in favour of IPDT were found for comorbid anxiety, emotion regulation and self-compassion.

    Study II explored participants’ (n = 18) experiences of the psychotherapeutic relationship in IPDT. Semi-structured interviews were analysed using thematic analysis. Four themes were created: “a meaningful and significant relationship with someone who cared”, “a helping relationship with someone who guided and motivated me through therapy”; “a relationship made safer and more open by the fact that we didn’t have to meet”; and “a nonsignificant relationship with someone I didn’t really know and who didn’t know me”.

    Study III examined the relationship between therapeutic alliance, emotion regulation and outcome week-by-week in IPDT and ICBT for adolescent depression (n = 272). Results showed that therapeutic alliance, as rated by both therapist and participant, predicted outcome in depressive symptoms week-by-week in both treatments. Furthermore, this relationship was mediated by emotion regulation, again in both treatments.

    In conclusion, results from this thesis indicate that IPDT may be a viable treatment option for adolescent depression. Furthermore, it is possible to form a close and safe relationship between therapist and participant, experienced as important for the psychotherapeutic process by many participants. Lastly, therapeutic alliance plays an important role in both IPDT and ICBT for adolescent depression, partly through its effect on emotion regulation.

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  • Public defence: 2023-10-05 13:00 hörsalen, BUV 110, Frescati backe, Stockholm
    Olsson, Maria
    Stockholm University, Faculty of Social Sciences, Department of Child and Youth Studies.
    Galna kameror och barns virtuella bildseende, bildtänkande och filmgörande i förskolan2023Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The aim of this thesis is to contribute knowledge about children’s image-vision, image-thinking and image- and filmmaking in preschool, through a collaboration with children and digital film technology, and about Gilles Deleuze’s film philosophy (1989) as well as digital videography and the methodology created in the research process. The empirical production was carried out as a digital decentralized videography, according to Pink et al. (2016), over a period of about 12 months. A total of 29 children participated in filmmaking at filmings and screenings collected in fifteen film event-logs. The researcher follows, films and interacts with the children’s filmmaking. Deleuze’s transcendental empiricism makes it possible to think about the indeterminable that is triggered in filmmaking as movement and change. Thus, internal differences are established as an immediacy between thinking and being. Feeling and being in itself can be understood as a form of consciousness in its ’own right that is both definite and indefinite. The form of the indeterminable becomes determinable within time. Deleuze’s concept crystal-image works in the analyses, unfolding the concepts mirror-image, recollection-image as well as ritornello and gallop. The concept mirror-image works as an image with two sides, the current and the virtual. In one chapter of the thesis, the researcher accompanies the children Andreas and Hanna’s filmmaking. The image of a common virtual vision is made visible and actually becomes with the digital film cameras and the speech about who sees whom. In a second chapter, the children Kim and Erik film to try to see a ghost that Erik remembers seeing in the room outside the toilets. With the concept recollection-image, the memory of a virtual ghost from the past can be re-played and actualized in the present and become visible. In a third chapter, the concepts ritornello and gallop set parallel images of time in motion towards the future. It is about how the children Isak and Rebecka film and play on rhythmic instruments. The children play their film on a screen and imitate their own movements that are visible on the screen. With the gallop, the world is coming to an end and the ritornello creates the beginning of the world possible, and takes it away from time. The results of the thesis contribute knowledge about how children’s and adults’ interaction with digital film technology can open opportunities for children and adults to interact and rethink the reality of the surrounding environment with digital film. This shows the importance of understanding how relationships between materialities, images and life in preschool are connected. In addition, the thesis contributes knowledge of how a continuous alternation between images of the actual, visible, and the virtual, invisible, can emerge in children’s filmmaking. This makes it possible to follow the children through digitized time passages and retrieve memories from the past and place them in the present, and also in the future. The thesis thus raises new questions about what kind of virtual images of realities can become available and also visible and actual, in the meeting between children’s image-vision and digital film technology.

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  • Public defence: 2023-10-06 09:00 Vivi Täckholmsalen (Q-salen), NPQ-huset, Stockholm
    Serandour, Baptiste
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Ecological niche dynamic, lessons from plankton2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Abiotic conditions shape biological communities around the globe. Through spatial and temporal heterogeneity, environments impact plankton physiology, phenology and distribution. Understanding the dynamic relationships between biotic and abiotic components is essential to assess the resistance and resilience of biological communities to environmental changes. In an intricate interaction network, plankton organisms are channeling energy to higher trophic levels. However, the relative importance of the different energy sources and trophic pathways within the pelagic food web remains to be quantified. A better comprehension of the ecological niches of the main plankton species, and the influence of abiotic conditions on their interaction network is needed to enhance our understanding of fluxes and predicting the response of oceans to environmental change. 

    In this thesis, we employed diverse approaches to explore the influence of environmental conditions on feeding interactions and spatial distribution of Baltic Sea plankton species. Using metabarcoding tools, we show the broad trophic niche of mesozooplankton species and shed light on the diet variability across species belonging to a similar size class. Additionally, we observed for some species, the ability to change trophic behavior on a spatial and temporal scales. These new insights were incorporated in flux models to quantify energy pathways, which revealed the essential role of cyanobacteria in supporting the pelagic food web. However, biotic interactions are sensitive to abiotic conditions, therefore, expected environmental changes could lead to modifications in the marine network. We assessed the influence of changes in abiotic parameters on the spatial and seasonal distribution of key Baltic Sea species by projecting their suitable habitat areas in both current and future conditions. In this doctoral project, we unveil the future loss in habitat suitability of several important zooplankton species of the Baltic Sea food web, potentially leading to cascading effects. In addition, we mapped the distribution of suitable habitats of the newly introduced Cnidarian species Blackfordia virginica to the Baltic Sea. We show that a notable proportion of coastal areas present favorable levels of environmental parameters for the growth of this species, which could alter the pelagic communities in these regions.

    Overall, this thesis refines our comprehension of the trophic interactions, illustrates the role of cyanobacteria in the Baltic Sea and projects potential modifications in zooplanktonic communities, through changes in habitat suitability levels and invasion, due to expected changes in abiotic conditions.

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  • Public defence: 2023-10-06 10:00 hörsal 4, hus B, Stockholm
    Golmohammadi, Gloria
    Stockholm University, Faculty of Law, Department of Law.
    Realizing the Principle of Participatory Democracy in the EU: The Role of Law-making Consultation2023Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis sheds light on an EU foundational principle, the principle of participatory democracy and assesses its implications for EU multi-level law-making, focusing on how the principle can be given expression through consultation. It is clear from the primary Treaty article giving shape to the principle of participatory democracy, that consultation is a key duty. This doctoral thesis offers a contribution to understanding how law-making consultation can advance the realization of the principle of participatory democracy. It focuses on consultation as a multi-level phenomenon occurring at the EU and national level, using Sweden as the reference case. The thesis first unpacks the principle of participatory democracy, tracing its origins and theoretical underpinnings and identifies key legal rights and obligations flowing from the principle. Drawing on case studies, current law-making consultation practices at the EU level and national Swedish level are assessed to determine to what degree they adhere to or conflict with the identified key legal obligations. Based on this analysis, suggestions are offered to improve the quality of consultations so that the realization of the principle of participatory democracy is significantly advanced. 

    The thesis demonstrates that the Commission is legally obliged to consult widely and transparently prior to proposing legislation, as well as attend to equality of access to consultation opportunities and provide consultation feedback. The analysis shows that judicial review for certain EU law-making consultation requirements is possible, while procedural hurdles weaken this redress mechanism. The legal analysis also reveals that Member States are under an obligation to interpret national law in light of citizen’s right to participate in the democratic life of the Union. The thesis shows how this Treaty right refers to both representative and participatory democracy mechanisms and includes the right of citizens to know and attempt to influence EU legislative decision-making at the EU and national level. A legal interpretation of the Swedish constitutional duty to consult, in light of the principle of participatory democracy, extends the Swedish government’s obligation to consult in the formulation of its negotiation positions in the Council. In mapping out the legal imperatives of the principle, two main obligations for Commission consultation are identified; active transparency in the form of consultation feedback and procedural equality. In addition, the duty of the Swedish government to consult at the national level in preparing negotiation positions is noted. The case studies demonstrate that the procedural requirement of feedback can be applied effectively to the Commission’s consultations whereas the obligation of attending to equality is less straightforward. The case studies also suggest a gap between the legal imperatives of the principle of participatory and consultation practices for selected key obligations at the EU and national level. Five lines of action are suggested in order to elevate consultation to a participatory democracy practice, centered on: feedback, procedural equality, democratic innovation, multi-level coherence and consultation as an EU secondary law strategy.

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  • Public defence: 2023-10-06 13:00 De Geersalen, Geovetenskapens hus, Stockholm
    Kapás, Rozália E.
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Grassland restoration: Connectivity, plant community change and cows2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The ecological significance of semi-natural grasslands is high because these habitats provide a home for a diverse flora and fauna and support a range of associated ecosystem services. Due to large-scale land-use changes the extent of grassland habitat has declined. Hence, restoration efforts to mitigate grassland losses are now being prioritized across the globe and there is an increasing need to understand the drivers behind the recovery of degraded habitats. Since many restoration initiatives rely on spontaneous dispersal of plant species from sources at both local- and landscape-scales, community assembly is influenced by a range of factors which interact both over time and across spatial scales. Given this complexity over the scales, gaps remain in our understanding of how post-restoration management can be designed to facilitate the effective dispersal and establishment of target species in restored grasslands.

    In this thesis, I examined colonization patterns in Swedish grasslands by comparing plant communities in both ancient and restored grasslands and under contrasting management regimes. At small spatial scales and over the short-term following restoration, I investigated species recruitment sources and their relative contribution to colonization and regeneration. At larger temporal and spatial scales, I examined how the composition of vegetation and seed bank communities is determined by local environmental factors together with distance to species pool and presence of grazing livestock.

    I found that species mostly colonized spatially from local species sources through seed rain. The seed bank contributed to species colonization to a greater extent in ancient grasslands than in restored grasslands. Management through livestock grazing and shorter distance to species pool were positively associated with the number of species found in grasslands. Grazing livestock facilitated target species establishment into restored sites and the differences between ancient and restored grassland communities were smaller when grazing was active, highlighting that ancient sites can provide a source of colonizing species for restored sites. I found that plant species associated with former land-use declined immediately following restoration, while the occurrence of target species generally increased. However, there was a high initial stochasticity in the establishment of the target species and communities in restored grasslands were still distinct from continuously managed sites even after several decades.

    These results demonstrate that species presence in nearby ancient grasslands and potential dispersal from the local seed sources drives species colonization in restored and ancient grasslands. Livestock grazing was shown to be an important driver of grassland recovery, either by mediating spatial dispersal of seeds or improving site conditions for establishment. Target species are able to accumulate in the vegetation and seed bank over the long-term, as restored grasslands age. This accumulation will ensure an increasing resilience of grassland communities against future disturbances or changes in the climate. However this depends upon active management, for example by implementing management plans which include continued livestock grazing, and upon conserving remaining ancient grasslands as hotspots for biodiversity within the wider landscape.

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  • Public defence: 2023-10-06 13:00 Aula Nod, Nod huset
    De Alwis, Sulakshana
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences. Abertay University, School of Business, Law and Social Sciences, Division of Accounting.
    Technology-Assisted Supplemental Work in Sri Lanka: The Role of Information Communication Technologies in Work-life Boundaries and Work-life Conflict2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Due to increased affordability and accessibility, information and communication technologies (ICTs) are omnipresent in the daily lives of many individuals and consequently influence how people think, feel, and react in day-to-day life experiences. Workplaces are increasingly becoming less bounded by place and time, and employees can connect with work anywhere, anytime. The limitless connectivity enabled by ICTs has created paradoxical experiences for employees. On the one hand, connectivity increases flexibility, empowering employees to work whenever they prefer and wherever they want to be. On the other hand, connectivity creates after-hours expectations where employees are expected to be available anytime to work (i.e. Technology-Assisted Supplemental Work - TASW). However, ICTs alone cannot create these paradoxical experiences, and it is the constitutive entanglements between ICTs, social, organisational and individual factors that create paradoxical experiences. Employing the sociomaterial perspective, in this thesis, we looked at how ICTs have become entangled with different social, organisational, and individual factors in the work-life boundary experiences of individuals and how these entanglements contribute to Technology-Assisted Supplemental Work (TASW) and the work-life conflict of employees. 

    The findings showed that TASW and work-life boundary experiences are outcomes of complex web relations between different sociomaterial assemblages. The flexibility availability paradox is an outcome of these constitutive entanglements between ICTs and human factors. Hence, the same technological constellations could create different boundary experiences for individuals due to the specific nature of the entanglements. Cultural values such as collectivism and power distance could elevate after-hours expectations if top management support such work norms. The findings also showed that female employees can be further disadvantaged due to TASW, especially if they are from a society that upholds traditional gender norms. In such circumstances, introducing technology as a facilitator of work-life balance through flexibility is questionable. All in all, the entanglement of ICTs with social, cultural and individual factors can decide the work-life conflict of employees. These findings suggest that the role of technology needs to be conceptualised carefully in work-life research. Assuming technology to be an exogenous factor or completely absent from work-life experiences will not give a complete picture of the work-life experiences of individuals. Thus, looking at work-life experiences from the sociomaterial perspective would assist researchers in finding more richer insights about this phenomenon and such new insights would be beneficial for organisations to implement formal guidelines to manage TASW requirements to reduce the negative consequences of TASW. 

     

     

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  • Public defence: 2023-10-06 13:00 sal FB53, AlbaNova, Stockholm
    Tempest, Kajsa-My
    Stockholm University, Faculty of Science, Department of Physics.
    Three-body Universality Controlled by a Feshbach Resonance2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The quantum Efimov effect manifests itself in the limit of resonant two-body interactions, where the scattering length diverges. In this scenario, an infinite number of shallow bound trimer states are formed with binding energies that obey a discrete geometric scaling law. The effect is universal in the sense that it can, in principle, appear in any system of bosons with resonant interactions. These states have been studied experimentally in dilute gases of ultracold atoms, where the magnetic-field-dependent coupling to a different molecular state, i.e., where a Feshbach resonance, can be used to tune the scattering length to the resonant regime. A limited number of Efimov states can also be formed for scattering lengths of finite magnitude. As experimental observations of these states accumulated, an unexpected regularity was found in the value of the scattering length where the first Efimov state emerges from the three-body continuum. This regularity is commonly referred to as van der Waals universality. It is believed to exclusively appear when broad Feshbach resonances are used to tune the scattering length. Theoretical predictions suggest a different kind of regularity for narrow Feshbach resonances, but the few experimental observations that exist are inconclusive in regard to these predictions.

    This thesis summarises the methodology I have used for developing a multichannel model that includes a magnetically tunable Feshbach resonance used for varying the scattering length. With this model, I am able to study effects related to the resonance width, which the commonly used single-channel models are unable to capture. By solving the Schrödinger equation in the adiabatic hyperspherical approximation, I obtain three-body hyperradial potentials, which I subsequently use to obtain the discrete Efimov energy spectrum. The origin of the van der Waals universality is believed to be caused by a universally positioned repulsive wall in the three-body effective hyperradial potential responsible for the Efimov effect. I observe a slight shift in the position of this wall as the system approaches the narrow resonance limit. More notably, the attractive well becomes exceedingly shallow. In the Efimov energy spectra, I find a clear dependence on the width of the resonance and the position of the first appearing Efimov state. The results agree qualitatively with the predictions of others but for the narrow resonance, there is a large quantitative difference. The observed scaling between consecutive Efimov states agrees well with Efimov's prediction.

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  • Public defence: 2023-10-06 13:00 hörsal 9, hus D, Stockholm
    Woods, Joanna
    Stockholm University, Faculty of Humanities, Department of English.
    Of Imagined and Potential Futures: Speculative Fiction in Southern Africa, 2008-20182023Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This research project explores the rhetorical function of contemporary Anglophone speculative fiction (sf) in southern Africa. Focusing on short fiction produced between 2008 and 2018, the project delineates this literary production both theoretically and historically. It is the “difference” of contemporary African sf that needs attention, the thesis argues, and through such difference we might evaluate how this literature manifests as a prominent, collective call to de-colonise dominant ways of seeing.

    Moreover, the contemporary sf scene in the southern region of the continent is not well represented in scholarship. To date, much more work has been done on, for example, sf in Nigeria, or indeed in South Africa. Similarly, far more studies exist on the novel form. And yet, it is a contention of this project that short sf is far more abundant in Africa today. The project therefore addresses important gaps by providing perspective on short sf in Malawi, Zimbabwe, and South Africa. It also draws attention to various questions that will need further study in the field of Afrofuturism and Africanfuturism.

    The methodological choice to view this literature within a rhetorical framework complicates the duality of culture and text characteristic of cultural studies and focuses instead on how relationships among texts, writers, publishing agents and readers function. This is especially relevant in an African literary studies context because such approach works to bypass practices of silencing and the appropriation of certain perspectives, reorients agency, and redirects the conversation to focus on interactions between literary actors more closely. Since little attention has been paid to African literary narratives from a rhetorical angle, even less to African speculative texts, an effort is made to create a new lens using pragmatic frames (Bitzer 1968), rhetorical narrative studies (Phelan 2007), and the “literary field” (Bourdieu 1993). In addition, the project draws insights from the social sciences to combine quantitative and qualitative methods of investigation.

    The thesis consists of an introduction and three main chapters: “Mapping the Field”, “Ways of Seeing – Temporalities”, and “Ways of Seeing – Spatialities”. It also includes an Excel spreadsheet, in which much mapping of the scene occurs. Along with notes on authorship and production, the spreadsheet contains documentation of keywords noted while reading the stories. Three keywords made themselves most manifest: time, space, and ways of seeing, and thereafter helped to structure the project’s chapters. The findings in the spreadsheet and interview material particularly inform Chapter One, which illuminates the emerging field of sf in the southern region of Africa by mapping the scene of production (2008-2018). Chapter Two investigates the rhetorical function of time and temporalities as nodes of interest in five sf texts. It investigates how time is deployed as rhetorical “resource” (Phelan 2007) in stories by Ivor Hartmann, Stacy Hardy, Tendai Huchu, Wesley Macheso, and Mohale Mashigo. The third chapter, finally, explores to what effect space and spatialities are employed by sf writers in another five short stories. It argues that interest in space, as conceived as “heterotopia” (Foucault 1967), in stories by Cristy Zinn, Tendai Huchu, Andrew Dakalira, Stephen Embleton, and Shadreck Chikoti provoke specific “structures of feeling” in the sf scene today.

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  • Public defence: 2023-10-06 14:00 Gamma2 - Air&Fire - G2690, Solna
    Pozzati, Gabriele
    Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics.
    Deep learning solutions to protein quaternary structure2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Interactions between proteins are directly involved in most biological processes and are essential for the correct functioning of every form of life. The nature of protein-protein interactions allows functional assemblies of hundreds of protein chains. Given the enormous complexity and the pivotal role of protein interactions in life’s mechanics, the necessity to obtain a complete comprehension of such mechanisms is just as big as the challenge to achieve such knowledge. In the last few decades, experimental procedures constantly improved, dramatically increasing the available structural data for protein interactions. Unfortunately, experimental methods require a lot of time and resources and cannot always be applied with the same degree of success. Several computational methods have been developed in parallel with experimental procedures to overcome such limitations. Therefore, this thesis focused on screening existing computational methods and adopting them to improve the overall accuracy in solving structures of protein-complexes. In the first paper, I propose a simple rigid-body docking framework to test several interface predictors and their ability to drive a protein-protein docking procedure. Next, in the second paper, I display a method to adapt the trRosetta deep neural network to predict inter-residues distances and dihedral angle constraints for full protein complexes. The same concept is then improved in the third paper with FoldDock, an adaptation of Alphafold2 to work on multiple protein sequences and produce the corresponding complex. Finally, in the fourth paper, the FoldDock pipeline is applied to a large dataset of protein pairwise interactions derived from the hu.MAP and HuRI datasets, resulting in the characterization of more than 3000 high-confidence structural models.

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  • Public defence: 2023-10-12 13:00 Högbomsalen, Geovetenskapens, 3rd floor, Stockholm
    Aminjafari, Saeid
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Monitoring Water Availability in Northern Inland Waters from Space2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    River deltas and lakes support biodiversity and offer crucial ecosystem services such as freshwater provision, flood control, and fishing. However, climate change and human activities have affected deltas and lakes globally, altering the services they provide. Since delta and lake surface water occurrence and water levels respond to climate change and anthropogenic activities, we need to monitor their variations to understand the potential drivers for effective water management strategies. However, important deltas like the Selenga River Delta (SRD) in Russia lack a detailed analysis of water occurrence. Regarding lake water level, there has been a decline in the number of gauging stations globally, due to installation and maintenance costs. For example, Sweden has ~100,000 lakes which are sources of freshwater and hydro-power, but only 38 lakes have long and continuous in-situ records of water level.

    As satellite data are reliable alternatives for conventional methods to monitor deltas and lakes, I employed Earth Observations (EO) to quantify changes in surface water occurrence in the SRD and water levels in Swedish lakes and identify their main drivers. I also developed and explored a novel methodology for lake water level estimation based on Differential Interferometric Synthetic Aperture Radar (D-InSAR) by calculating the six-day phase differences in 30 Swedish lakes.

    To achieve these objectives, I trained and applied a Maximum Likelihood classification to Landsat images from 1987 to 2020 and quantified surface water occurrence and its changes in the SRD. I found that surface water occurrence in 51% of the delta experienced a decrease. As the Selenga River is the only river flowing into the SRD, the change in surface water occurrence in the SRD correlated with river discharge, but not with the river suspended sediment concentration, the lake water level in the outlet of the SRD, or evapotranspiration over the delta.

    In Sweden, I used satellite altimetry data from ERS-2, ENVISAT, JASON-1,2,3, SARAL, and Sentinel-3A/B to quantify water levels in 144 lakes from 1995-2022. I found that 52% of the lakes showed increasing trends (mostly in the north) and 43% decreasing trends (mostly in the south). Water level trends and variabilities did not correlate strongly with hydroclimatic changes (precipitation and temperature) but differed in regulated lakes compared to unregulated ones, both in the north and in the south of Sweden.

    The results of the D-InSAR method for water level estimation in two Swedish lakes (Hjälmaren and Solnen) showed that with water level changes smaller than a complete SAR phase, the phase changes correlate with in-situ water level changes with a minimum Root Mean Square Error of 0.43 cm in some pixels. In all 30 lakes, I accumulated the phase changes of each pixel throughout the whole number of interferograms to construct water levels. This method replicated the direction of water level changes shown by high Pearson’s correlations in at least one pixel in each lake.

    This thesis highlights the importance of EO for estimating surface water occurrence and lake water levels and brings focus to the future of EO through advanced space missions such as Surface Water and Ocean Topography (SWOT) and NASA-ISRO Synthetic Aperture Radar (NISAR). The findings underscore the need to continuously monitor lake water level and occurrence to adapt to climate change and understand the effects of water-regulatory schemes.

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  • Public defence: 2023-10-12 13:00 lärosal 4, hus 1, Albano, Stockholm
    Nussipova, Gulnar
    Stockholm University, Faculty of Social Sciences, Stockholm Business School.
    Unpacking the Value of Emerging Technologies: Experimentation, Communication and Knowledge Brokering2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    While many emerging technologies are making significant strides in the marketplace, others are developing at a slower pace. Historical experience has shown that their success can vary widely, from outright failure to becoming indispensable to daily life. The creation of value associated with emerging technologies has become a focal point for CEOs, business leaders, policymakers, and global forums such as the World Economic Forum. They actively explore opportunities for value creation using these technologies. Yet, the value of emerging technologies often remains uncertain since their adoption in new contexts and usage may deviate significantly from providers' intended use cases. The commercialization of emerging technologies presents a profound challenge due to the uncertain value and complex landscape of innovation.

    This thesis aims to investigate the processes that help unpack the value of emerging technologies to customers in a B2B context, with a focus on processes that recognize the evolving, dynamic nature of value. The thesis contends that co - creation processes help customers in unpacking the value of emerging technologies. Given the constantly evolving nature of emerging technologies, it is important to adopt a comprehensive perspective in order to fully comprehend their complex nature. In order to address the challenges presented by the uncertain value of emerging technologies in B2B settings, this thesis proposes a framework that focuses on three co-creation processes - experimentation, communication, and knowledge brokering - that may assist customers in unpacking the value of emerging technologies for their businesses. Finally, the thesis concludes with a discussion of its contributions, both theoretical and practical implications, and recommendations for further research.

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  • Public defence: 2023-10-13 13:00 Lilla hörsalen, Kista
    Firouzi, Ramin
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Distributed Intelligence for IoT Systems Using Edge Computing2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over the past decade, the Internet of Things (IoT) has undergone a paradigm shift away from centralized cloud computing to edge computing. Hundreds of billions of things are estimated to be deployed in the rapidly advancing IoT paradigm, resulting in an enormous amount of data. Sending all the data to the cloud has recently proven to be a performance bottleneck, as it causes many network issues, including high latency, high power consumption, security issues, privacy issues, etc. However, the existing paradigms do not use edge devices for decision-making. Distributed intelligence could strengthen the IoT in several ways by distributing decision-making tasks among edge devices within the network instead of sending all data to a central server. All computational tasks and data are shared among edge devices. Edge computing offers many advantages, including distributed processing, low latency, fault tolerance, better scalability, better security, and data protection. These advantages are helpful for critical applications that require higher reliability, real-time processing, mobility support, and context awareness. This thesis investigated the application of different types of intelligence (e.g., rule-based, machine learning, etc.) to implementing distributed intelligence at the edge of the network and the network challenges that arise. The first part of this thesis presents a novel and generalizable distributed intelligence architecture that leverages edge computing to enable the intelligence of things by utilizing information closer to IoT devices. The architecture is comprised of two tiers, which address the heterogeneity and constraints of IoT devices. Additionally, the first part of this thesis identifies a suitable reasoner for two-level distributed intelligence and an efficient way of applying it in the architecture via an IoT gateway. To mitigate communication challenges in edge computing, the second part of the thesis proposes two-level mechanisms by leveraging the benefits of software-defined networking (SDN) and 5G networks based on open radio access network (O-RAN) as part of a communication overlay for the distributed intelligence architecture. The third part of this thesis investigates integrating the two-tier architecture and the communication mechanisms in order to provide distributed intelligence in IoT systems in an optimal manner.

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  • Public defence: 2023-10-13 13:00 Auditoriet (215), Manne Siegbahnhusen, Stockholm
    Redbark Wallander, Ingrid
    Stockholm University, Faculty of Humanities, Department of Culture and Aesthetics.
    När dansen blev modern: Framväxt, formering och förändring av ett svenskt konstområde, 1930-19602023Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This dissertation, When Dance Became Modern (När dansen blev modern), deals with theatrical dance in Sweden between 1930 and 1960 from a historiographical perspective and assumes that dance is interwoven with socio-cultural contexts. The aim is to investigate what factors create the conditions for certain genres and aesthetics to emerge.

    The historiographical narrative that the investigation departs is largely concentrated on the Royal Theater. A narrative has been consolidated where the 1930s and 1940s are described as a period of decline in contrast to the radical change of the 1950s. The historiography is based on historiographical theories and methods where turning points are the focus, contrasts are identified, and the development of events is uneven. The thesis reviews the history of dance that contrasts traditional views of dance with an emerging, new aesthetic of dance–i.e., the traditional versus the modern.

    My point of departure is that when dance is established as an art form, it is woven together with various aspects of the emerging modernity. Therefore, how the field of dance, as a profession and aesthetics, took shape is examined. I highlight relationships other than purely aesthetic ones and also consider various genre expressions as part of the modern. Here, the framework includes modernity’s social changes, national cultural policy ideas, and in some cases the ideas within, for example, the translocal dance field.

    The intention to identify and analyze several contemporary phenomena in the sphere of dance has necessitated different types of sources. The empirical material consists largely of reviews, articles, program leaflets, and posters, but statutes and protocols are also used. Additional sources are dance history books, biographies, and memoirs as well as etymological books, dictionaries, encyclopedias, and legal texts and government investigations. Finally, the empirical material includes choreography in film and some interviews.

    In the thesis, I use a cultural theory model that combines three methodological approaches with associated methods: interviews, discourse analysis, and analysis of the historical context. The purpose of the multidimensional method is to create a space for agency for the individual that is both part of the discursive mediation and the socio-cultural context. Hence, I show how discourses about dance and the historical context work together to create “the modern” in dance.

    This study shows that many actors in different constellations collaborate to develop new structures that support “modern” ideas about dance, albeit these are often unstable constellations. During this period of change, professional categories such as dancer, choreographer, dance pedagogue, and dance critic crystallize as specialist areas. Transnational exchange takes place through international guest performances and through the dance practitioners who further their education and participate in competitions. Dichotomies between dance genres, aesthetic view, and different dance skills appear as the boundaries are constantly challenged and transgressed. Performance conventions change and ballet takes on a central role through full-length performances at the Royal Theater as well as touring that far exceeded that of the free dance movement. A significant expression of the modern is that the relationship between seemingly opposite positions is recurrently relevant in the dance field’s establishment phase.

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  • Public defence: 2023-10-13 14:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Patrick, Joan
    Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics.
    Functional dynamics of glycosyltransferases: Solution-state NMR studies of peripheral membrane proteins involved in glycolipid biosynthesis in bacteria2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Antibiotic resistance is an existential threat enabled by bacterial adaptation and fuelled by inappropriate use of medication. The ensuing shortage of effective treatments has led to a rise in deaths linked to resistant bacterial pathogens. Disrupting cell wall biosynthesis can undermine bacterial defences, so new insights into the dynamic function of the enzymes involved could facilitate new therapies.

    Glycosyltransferases (GTs), enzymes forming glycosidic bonds, build molecules by transferring a sugar group from a donor to an acceptor. In Gram-negative bacteria, an enzymatic assembly line constructs membrane-anchored virulence factor lipopolysaccharide (LPS), which dominates the outer membrane, forming a protective layer. In mycobacteria, phosphatidyl-myo-inositol mannosides (PIMs) ensure the stability and impermeability of the inner membrane, and are constructed by a similar array of enzymes. In this thesis, bacterial GTs that work at the cytoplasmic leaflet of the inner membrane were investigated.

    PimA is an essential mycobacterial enzyme involved in constructing PIMs. It exists in multiple conformations, implying that it undergoes complex conformational changes, including a fold-switch. Associated motions were characterised with NMR dynamics experiments, revealing donor substrate-dependent population shifts and dynamic changes. At least four different states co-exist in solution, regardless of whether or not the enzyme is bound to substrate.

    WaaG performs one step in the biosynthesis of LPS in bacteria including E. coli and P.  aeruginosa. As it is not an essential enzyme, EcWaaG-deficient E. coli survive, but are more vulnerable to antibiotics. 19F NMR was employed to detect conformational and dynamic changes in EcWaaG. Upon interaction with bicelle-bound lipids and its donor substrate, UDP-glucose, EcWaaG was shown to experience a dynamic change, while a part of the protein was shown to experience slow conformational change. Hydrolysis of the donor substrate was quantified using 31P NMR. WaaG from P. aeruginosa was also investigated, focusing on the functional mechanism. NMR experiments determined that only UDP-GalNAc was hydrolysed by PaWaaG. When the active site was mutated to resemble that of EcWaaG, it was shown by 31P NMR that the mutated enzyme instead hydrolysed the donor substrate of EcWaaG, UDP-glucose. However, PaWaaG cannot be substituted for EcWaaG in vivo, underlining the importance of the interaction with the lipid-bound acceptor substrate.

    Both WaaG and PimA function adjacent to membrane. As larger objects give rise to broader signals, solution-state NMR imposes constraints on the detection of protein-lipid interactions. Small membrane mimetics like lipid bicelles can be used to mimic a membrane, but while they permit detection of effects on protein signals, detecting the effects on lipid signals requires further optimization, as further concentration-dependent challenges arise in multi-component experiments. Thus, lipid dynamics in bicelles designed to exist at low concentrations were characterized using 1H and 13C NMR. Upon binding spin-labelled PimA, paramagnetic relaxation enhancement of the lipids could be observed.

    This thesis thus widens the toolkit available to study membrane-associated proteins. It demonstrates that, far from being static structures, biomolecules like lipids and proteins are highly flexible objects whose function can only be understood if dynamics are taken into account.

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  • Public defence: 2023-10-18 10:00 De Geersalen, Geovetenskapens hus, Stockholm
    Cremer, Roxana S.
    Stockholm University, Faculty of Science, Department of Environmental Science.
    Lifecycle of Black Carbon in the Arctic2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This PhD thesis investigates the atmospheric life cycle of Black Carbon (BC) in the Arctic. The Arctic region has been rapidly changing in the last decades and the role of BC aerosols in this is still uncertain. BC aerosols are mainly produced by incomplete combustion of biomass burning and fossil fuel and stand out from other aerosol species due to their strong ability to absorb solar radiation. The impact of BC on the Earth’s radiation budget is estimated to be overall warming. While the indirect effect, interactions with clouds, is estimated to be negative, the direct radiation effect is positive because of the absorption ability of the BC. These estimates are uncertain, especially for aerosol-cloud interactions. To estimate the role of BC in the Arctic, it is necessary to know the size distribution of BC, the transport pattern and the loss processes that affect the BC concentration. In this thesis, in-situ observations from the Zeppelin observatory in the Arctic, as well as global modelling tools, are used to answer the following research questions: 1. What kind of new insights about BC size distributions can be gained from simultaneous long-term measurements of absorption and aerosol number size distributions? 2. How do source regions impact BC size distributions measured at Zeppelin? 3. How are observations of biomass burning tracers at Zeppelin connected to transport from source regions with active fires? 4. How do emissions, as well as, wet and dry removal pathways drive the diversity of the BC life cycle in General Circulation Models (GCMs)?

    A statistical method to derive BC size distributions from filter-based absorption measurements was developed and applied to long-term data from the Arctic measurement station Zeppelin on Svalbard. Promising results were obtained for inferring BC number size distributions from absorption and size distribution data, except for the most polluted conditions with the air masses arriving from Northern Eurasia and Russia - as identified from an analysis using back trajectories. Trajectory analysis was also used to link events with elevated biomass burning tracers and BC at Zeppelin to fire activity measured by satellites on the continents around the Arctic. To investigate the interplay of emissions and removal processes of BC in models and to understand the diversity in model representation of BC in the Arctic, a detailed analysis of processes in four GCMs was performed. The BC concentrations in the Arctic were compared and their response to removal processes during long-range transport to Zeppelin. The results underline the importance of BC sources and processing far away from the Arctic.

    The knowledge gained about the BC life cycle will facilitate a better assessment of the large-scale influence of BC on the Arctic climate and environment.

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