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  • Disputation: 2020-05-26 13:00 Stockholm
    Geiger Poignant, Elisabeth
    Stockholms universitet, Humanistiska fakulteten, Institutionen för svenska och flerspråkighet.
    Tolkade publika författarsamtal: Berättande och triadisk interaktion över språkgränser2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    På bokmässor, litteraturfestivaler och internationella författarscener anordnas årligen en mängd publika samtal med utländska författare i Sverige, och i en del av dessa medverkar en tolk. Språkförståelsen hos både moderator, författare och publik varierar. Vad krävs för att författarens budskap går fram, för att samtalet blir intressant, underhållande och informativt för den svenska publiken? Hur påverkar närvaron av en tolk ett författarsamtal?

    I denna avhandling studeras sådana samtal som forskningsobjekt inom översättningsvetenskap. Studien fördjupar kunskapen om tolkade författarsamtal som ett litterärt och kommunikativt fenomen. I en av delstudierna kartläggs författarsamtalets utveckling som litteratur-evenemang och samtalens språkliga diversitet i Sverige under åren 1998–2018. I avhandlingens övriga delstudier undersöks samspelet i den tvåspråkiga kommunikationssituationen utifrån ett mikrosociologiskt, samtals- och interaktions­analytiskt perspektiv.

    Multimodal analys av deltagarnas gester och prosodi belyser den tolkade turens roll i och effekter på den lokala turtagningsordningen. Narratologisk analys visar hur moderator, författare och tolk, oavsett att de rör sig fram och tillbaka över språkgränser, kan upprätthålla en obruten linje genom berättelsers olika spänningsmoment.

    Elisabeth Geiger Poignant vill med sin avhandling bidra till att öka kunskapen om tolkning som interaktionell kommunikativ praktik generellt, och specifikt om hur den tar form i publika tolkade författarsamtal.

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    Tolkade publika författarsamtal: Berättande och triadisk interaktion över språkgränser
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  • Disputation: 2020-05-27 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Subbotina, Elena
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Production and transformation of organic compounds from renewable feedstock: Catalytic approaches2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis is focused on the development of strategies for lignocellulosic biomass valorization. The thesis consists of two parts.

    The first part of the presented work is related to the catalytic fractionation of biomass (lignin-first approach) and the production of monomeric compounds from lignocellulose. In the first project (Chapter 2) we have established a process to study the transformations occurring during the catalytic organosolv pulping of wood in the presence of Pd/C. This was achieved by performing a fractionation under continuous-flow conditions. In the designed process, the pulping and the transition metal catalyzed reactions were separated in space and time. Thus, the role of the solvolysis and the transfer hydrogenation reactions were studied independently. We discovered that during the solvolysis of wood, a substantial amount of monomeric lignin fragments are released into the solution. The main role of the catalyst is to stabilize these monomers and prevent their repolymerization. Based on the obtained knowledge we developed a new version of the lignin-first approach (Chapter 3). In this process zeolites were used as shape-selective catalysts. We have demonstrated that by tuning the size of pores of the catalyst the undesirable bimolecular reactions can be minimized. Furthermore, the released monomers can be converted into stable products via transfer hydrogenation reactions.  

    The second part is related to studies of dimeric and trimeric lignin model compounds. In Chapter 4, the reactivity of the dibenzodioxocin motif, which is considered a main branching point in the lignin structure has been investigated. We have designed a protocol for the catalytic reductive cleavage of lignin model compounds representing this motif, in the presence of Pd/C and benign hydride donors. The cleavage of the dibenzodioxocin structure results in the formation of dimeric biaryl compounds. Unlike monomers, the valorization of lignin-derived dimers is less studied. The last chapter is focused on the transformation of biaryls into highly functionalized synthetic building blocks. This was achieved via a visible light induced dearomative spirolactonization of biaryl carboxylic acids. The synthetic value of the obtained products was demonstrated by the conversion of the products into more complex structures.

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    Production and transformation of organic compounds from renewable feedstock
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    Nailing Page Defence day 200527
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  • Disputation: 2020-05-27 10:00 Lilla hörsalen, Naturhistoriska riksmuseet, Stockholm
    Curtis, Reed T.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för pedagogik och didaktik.
    Without mast, without sails, without compass: Non-traditional trajectories into higher education and the duality of the folk-market2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    In 1809, the trajectory of Swedish history and the identities associated with the country changed after Finland was lost to Russia. Swedish General von Döbeln explained that the loss left the nation "without mast, without sails, without compass." The research within this dissertation is not of war but of a similar sense of loss. The loss of the folk-home.

    Through an abductive case-study of present-day students entering higher education, the author explores the sociocultural history of Sweden, the Swedish education system, student self-efficacy beliefs, and the educational trajectories students experience on their way into higher education. This research uses a mixed methods design where a quantitative survey and qualitative narrative interviews complement each other. First, students within an introduction to university learning summer course at a large research university in Sweden completed a psychosocial survey measuring their self-efficacy beliefs about their academic skills and career decision making abilities. A statistically significant correlation was found between the two measures. 

    Second, 11 students from the same course participated in narrative interviews where they detailed their educational trajectories between upper-secondary education and higher education. The author constructed, analyzed, mapped, and discussed each narrative using careership and social cognitive theory. Students within this study suggest that their transition between compulsory education and upper-secondary education was particularly impactful and shaped their self-efficacy beliefs and educational trajectories into higher education. Students describe a lonely process of upper-secondary education decision making at the age of 15 when they were sent to market without preparation, without support, and without the necessary tools. The majority eventually changed academic programs and schools during upper-secondary education. This led to lengthy ruptures outside of formal education that significantly delayed their progress towards graduation. Students only later decided to pursue a non-traditional trajectory into higher education after the negative self-efficacy beliefs they developed during these ruptures were challenged externally.

    Lastly, previous research, theory, and the empirical findings were systematically combined through an interactive process of abduction. First, the author developed the concept of the folk-market, which better represents the current neoliberal welfare model present in late modern Sweden. The folk-market must be understood as a duality. The folk-market is both a market for folk and a market of folk. Citizens are both the consumers and the consumed. Second, the author presents folk-market theory, which suggests that neoliberal reforms that embed markets within welfare systems alter transition regimes, redirect state responsibility, and distance the connections citizens have with the state. Therefore, the findings suggest that notions of statist individualism misrepresent late modern Sweden. The relationships individuals and families have with the state are now indirect and filtered through the folk-market. This study also indicates that though Swedish, neoliberal, and adolescent narratives of "autonomous youth" are unrealistic, they directly shape educational policy in Sweden. As such, many students in Sweden are left navigating a competitive folk-market without mast, without sails, without compass.

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    Without mast, without sails, without compass
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  • Disputation: 2020-05-27 14:00 Nordenskiöldsalen, Geovetenskapens Hus, Stockholm
    van Vlokhoven, Has
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Nationalekonomiska institutionen.
    On the Cost of Capital, Profits and the Diffusion of Ideas2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Estimating the Cost of Capital and the Profit Share Compensation of the factor of production capital is not directly observed since most firms own part of their capital stock. I develop a new method to estimate capital compensation. I show how firms' input choices reveal the user cost of capital when firms minimize costs and produce according to a homogeneous production function. Subtracting estimated capital compensation together with all other observed costs from sales gives economic profits. Estimating the model using Compustat data, I find that the cost of capital has been declining, and that the profit share has been increasing over the past fifty years from around 4% to around 8% of sales. The increase in the profit share coincides with the observed fall in the labor share, while I estimate the capital share to be falling as well. Therefore, the fall in the labor share is not due to an increased capital intensity, but due to an increase in profits.

    Profits and the Marginal Product of Capital Around the World The extent to which marginal products of capital are equalized across countries is informative of how well international capital markets function. I estimate the marginal product of capital across a wide range of countries while allowing for imperfect competition. I find that richer countries have a higher marginal product of capital than poorer countries, but that this is entirely driven by differences in depreciation rates. Thus, in terms of output net of depreciation there is no gain by reallocating capital from poor to rich countries or vice versa. Furthermore, I find that profits have increased globally, but that the rise in profits is more pronounced in rich countries.

    The Life Cycle of Profits Old firms make more profits than young firms, and nowadays profits are more back-loaded than thirty years ago. I study to what extent this changing life-cycle pattern of profits explains the observed rise in profits and fall in firm entry. I build a quantitative life cycle model with oligopolistic competition and an occupational choice between being an entrepreneur and being a worker. All else equal, the more back-loaded profits are, the lower the value of the firm due to discounting, and therefore the fewer agents choose to be an entrepreneur. In equilibrium, aggregate profits rise to a level such that agents are indifferent between occupations. I find that the observed change in the life-cycle pattern of profits explains about two-thirds of the rise in profits, and more than fully explains the fall in firm entry.

    Diffusion of Ideas in Networks and Endogenous Search I study the diffusion of technology when the decision to search for productivity-enhancing technologies depends on the network of interactions between agents. Agents have the option to engage in costly learning from their first-degree connections. The more productive an agent's connections, the more willing it is to learn. Hence, the network affects the reservation productivity at which agents choose to learn and affects therefore aggregate productivity. I find that the denser the network, the higher learning effort and therefore the higher total factor productivity and the lower inequality. However, the effect of the network on the share of agents that learn in equilibrium is ambiguous. Furthermore, I find that nodes that are central in terms of their closeness to other nodes tend to exert more learning effort and have a higher productivity.

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    On the Cost of Capital, Profits and the Diffusion of Ideas
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  • Disputation: 2020-05-28 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Toth, Alexandra
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Significance of mitochondrial ultrastructure for bioenergetics2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Mitochondria are the site where most of the energy from food is converted into adenosine triphosphate (ATP). This process is taking place at the inner membrane (IM) of mitochondria, and is called oxidative phosphorylation, and results in the establishment of a proton motive force (pmf). The proton motive force is a combination of a proton difference over the mitochondrial IM and a charge difference. The ATP is then synthesized by the ATP synthase, which is utilizing the pmf for this process. The IM of mitochondria has many invaginations, which are called cristae. The enzymes of the respiratory chain are mainly located at the flat sheet part, while the ATP synthase is located at the rim of the cristae. The hypothesis arises whether the cristae membrane would serve as a proton sink for the ATP synthase, due to the curved shape of the cristae. We aimed at answering this hypothesis by attaching a pH-sensitive green fluorescent protein (pHluorin2) at different locations within the mitochondria. The study revealed that there is no substantial pH difference across the IM of yeast mitochondria and that the cristae are not functioning as a proton sink, but rather its main function is to provide an optimal environment, for coupled enzymatic activity. The second project investigated the importance of the mobile electron carrier; cytochrome c (cyt c) of its ability to freely diffuse along with the IM. Cyt c is the electron carrier between the bc1 complex and cytochrome c oxidase of the respiratory chain. It is also involved in programmed cell death (apoptosis) of higher eukaryotes, where its release from mitochondria initiates apoptosis. As its role in yeast apoptosis is not entirely clear, we created a yeast strain where cyt c was tethered to the IM, in a background strain that was devoid of the mobile cyt c. Interestingly, the level of apoptosis was higher in the yeast strain with the non-mobile cyt c, which indicated that cyt c release in yeast is not a necessary step to initiate apoptosis. The strain with the IM tethered cyt c had also higher levels of reactive oxygen species (ROS), shorter life span, alterations of the mitochondrial network in comparison to the wild type strain. Despite not showing any major alterations in the respiratory chain, the mutant yeast strain had elevated oxygen consumption, indicating a compensatory mechanism, which could have caused the elevated ROS levels which ultimately induced apoptosis. Maintaining a steady level of ATP is crucial for the cell, and one such mechanism in higher eukaryotes is the creatine phosphate shuttle system, by the enzyme; creatine kinase. Creatine kinase is catalyzing the phosphorylation of creatine in mitochondria, and the phosphocreatine is transported out to the cytosol, where the cytoplasmic isoform of the enzyme is regenerating ATP from the phosphocreatine. A yeast strain was created to express the mitochondrial creatine kinase, which could serve as a strategy in industrially relevant yeast strains, to circumvent ATP levels to drop during the production processes. To gain an understanding of the importance of cyt c diffusion, its relevance for the respiratory chain, the yeast strain from the second project was modified so that it was fused to the bc1 complex. The strain showed a functional respiratory chain, and further work will provide insights into the diffusion of the respiratory complexes and their interaction with the IM.

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    Significance of mitochondrial ultrastructure for bioenergetics
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  • Disputation: 2020-05-28 13:00 Bergsmannen, Aula Magna, Stockholm
    Adamsson, Emelie
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Företagsekonomiska institutionen.
    The Construction of Corporate Irresponsibility: A constitutive perspective on communication in media narratives2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Stories in which corporations are revealed as irresponsible are frequently published and broadcast in journalistic media. These media stories, as well as stories from other stakeholders, contribute to the formation of counter-narratives that consequently stand against corporate narratives with a focus on responsibility. Since corporate irresponsibility is a value judgment attributed by others, narratives about corporations in the media can have particular importance for meaning construction. The aim of this study is accordingly to explain how corporate irresponsibility is constituted in these narratives, by focusing on how corporate irresponsibility is constructed in media stories. The study takes its theoretical departure in the communicative constitution of organizations (CCO) perspective and consequently sees communication as the primary constituent of corporate irresponsibility. A narrative approach is also added by highlighting narratives as a particularly powerful form of communication. The empirical starting point for the study is two long-running media stories that are analyzed qualitatively based on material gathered both from print and broadcast media and from interviews. The findings show that the construction of corporate irresponsibility in media stories can take different forms, in this study represented by chronic irresponsibility narratives and acute irresponsibility narratives. By understanding how these two types of narratives differ from each other, it is recognized that meaning construction is not a given and can take various forms depending on the underlying negligence or irresponsibility issues. The study shows that it is in the meetings of the narratives in particular that opportunities for discussion and dialogue arises. It is consequently suggested that it is when narratives collide that communicative events, in which the meaning of corporate irresponsibility is negotiated and re-negotiated, most likely appear. This study therefore concludes that when arguing that communication is the primary mode through which the organization is constituted, narratives told about the corporations, by media and other stakeholders, should also be included in the analysis. The study thus contributes to the CCO perspective by applying the ideas of constitutive communication to narratives told neither inside nor outside the organization. Based on the results of the study, it is argued that the formation of narratives has consequences for understandings about corporate irresponsibility, both for the corporation in the media limelight and for society in general.

     

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    The Construction of Corporate Irresponsibility
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  • Disputation: 2020-05-29 10:00 David Magnussonsalen (U31), Stockholm
    Miloff, Alexander
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen.
    Virtual reality exposure therapy for spider phobia2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Exposure therapy for specific phobia involving systematic and repeated presentation of an aversive stimuli or situation is a highly effective treatment for reducing fear and anxiety. Dissemination of this evidence-based treatment has proved challenging, however, and for over 20 years an alternative method of delivery using virtual reality technology has been explored with positive results. This thesis consists of three empirical studies examining a new generation of virtual reality exposure therapy (VRET) that by using automation, inexpensive hardware, and downloadable software aims to ensure that a highly efficacious exposure therapy can be made available to almost anyone. Study I evaluated the efficacy of this novel automated VRET for spider phobia as compared to gold-standard in-vivo one-session treatment (OST) using a randomized non-inferiority design. Results indicated that large effect size reductions in self-reported fear were evident at post-assessment in both treatments and the automated VRET was not inferior to OST at 3- and 12-months follow-up according to behavioral approach test, but was significantly worse until 12-month follow-up. No significant difference was noted on a questionnaire measuring negative effects of treatment. Study II conducted a process measure evaluation of patient alliance towards the virtual therapist used in the VRET treatment with a purpose-built questionnaire entitled the Virtual Therapist Alliance Scale (VTAS). Exploratory factor analysis indicated a sound two-factor solution composed of a primary task, goal and co-presence factor and a secondary bond and empathy factor. Psychometric evaluation of the VTAS suggested good internal consistency, and a moderate correlation between the VTAS and change in self-reported fear over follow-up. Study III assessed what individuals with a fear of spiders found most frightening about spiders. Both quantitative ratings and qualitative descriptions indicated that movement characteristics were reported as most fear provoking and to a lesser extent appearance characteristics, however factor analysis of scores in these categories did not find a correlation with participant baseline self-reported fear. Overall, the above findings suggest that VRET is a potential alternative to OST for the treatment of spider phobia also with respect to therapist alliance, and spider movement characteristics should be emphasized in future VRET treatments.

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    Virtual reality exposure therapy for spider phobia
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  • Disputation: 2020-05-29 10:00 Nordenskiöldsalen, Geovetenskapens hus, Stockholm
    Lundström, Lina
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Barn- och ungdomsvetenskapliga institutionen.
    Att göra vänskap: En kultursociologisk analys av högstadieelevers sociala relationer2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This doctoral thesis explores how secondary school students perform friendship in a Swedish school. The thesis aims to describe and explain how cultural elements, such as an audience of peers, stages for friendship performances (e.g. classrooms), time, cultural norms and ideals, interact in the production of meaning that are part in the drawing of social boundaries. Processes that make certain performances of friendship possible and others challenging. Video recordings, interviews and field observations are utilised in order to analyse how friendships are performed in an educational setting where the cultural ideal is to have (many) friends. The thesis applies a cultural sociological perspective– spanning from Alexander’s theory on cultural pragmatics, Lamont and Molnàr’s work on boundaries in social life, to Goffman’s micro analysis of social interaction. The results illuminate the importance of understanding friendship as cultural performances and that these performances often require hard work. Such performances are affected by the way students ascribe meaning to the cultural elements. This means that the outcome of a performance is not decided beforehand but is dependent on when, where, with and in front of whom, friendship is performed. The performances of friendship are a process, and therefore it possible to study which cultural elements that come into play, how they affect and are affected by the performances and how dimensions of social power, for instance, inclusion and exclusion processes, are part of the performances of friendship. The thesis identifies two main empirical results. Firstly, it shows how students’ performances of friendship are dependent on the school as a physical, organisational and cultural stage. The cultural ideal is that friends should be freely chosen. However, school is not voluntary, which creates a duality that challenges the ideal of voluntary friendship. Students spend the majority of their time together on the same stage where they form memories of friendship and expectations of future relational work, such as how an authentic friendship ought to be performed. Time and stage are thus cultural elements that intertwine in the deciding where social boundaries for friendship are drawn, namely, which students that can be friends. The social boundaries can also be strengthened by referring to a collective background representation containing e.g. gender norms and ideals for friendship. Ideals that are reproduced as far back as Aristotle. Yet, since cultural elements and their ascribed meaning also are apt for change, unexpected friendship performances become possible. Secondly, cultural ideals of friendship, such as loyalty and generosity, work to draw boundaries within and around friendship constellations, working in inclusionary and exclusionary ways. There is a strong cultural force in the relational dynamics of the doings of friendship. The self-worth and cultural value of being part of a specific “us” comes through in the students’ relational work. Further, when an established way of performing friendship is threatened due to minor changes, such as new unexpected friendships, the students use disloyalty and stinginess. Thus, they use the opposite of the friendship ideals to draw boundaries. In this sense, the thesis illuminates how a constructed cultural ideal can have real consequences and influence the doing of friendship, through both inclusion and exclusion.

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    Att göra vänskap: En kultursociologisk analys av högstadieelevers sociala relationer
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  • Disputation: 2020-05-29 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Posevins, Daniels
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Advances in Stereoselective Palladium(ΙΙ)-Catalyzed Oxidative Transformations of Allenes2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Palladium(ΙΙ)-catalyzed carbon-carbon and carbon-heteroatom bond formation via selective C-H bond oxidation constitutes a step-economical and versatile approach towards complex target molecules. This thesis has been focused on the development of new selective palladium(ΙΙ)-catalyzed transformations of allenes under oxidative conditions catalyzed by either homogenous or heterogeneous palladium(ΙΙ) catalysts.

    The first part of this thesis describes carbocyclization-borylation of bisallenes, alkynylation of enallenes and preparation of [3]dendralenes from readily available allene starting materials. These homogenous palladium(ΙΙ)-catalyzed transformations involve selective allenic C-H cleavage under oxidative conditions. The aforementioned reactions can be carried out under aerobic biomimetic conditions by using electron transfer mediators (ETMs) and oxygen gas as the stoichiometric oxidant.

    The second part deals with highly diastereoselective palladium-catalyzed oxidative carbocyclization reactions of enallenes assisted by weakly coordinating functional groups, such as hydroxyl or sulfonamide groups. It was demonstrated, that this weak coordination is sufficient to trigger the allene attack on the metal center enabling formation of (vinyl)Pd(II) intermediates, previously achievable by the directing effect of unsaturated hydrocarbon groups. A broad range of borylated cyclohexanol derivatives, as well as cis-fused [5,5] bicyclic γ-lactones and γ-lactams were obtained with superb diastereoselectivity via palladium(ΙΙ)-catalyzed carbocyclization-functionalization reactions of enallenols.

    The final part of the thesis describes applications of the heterogenous catalyst Pd-AmP-MCF in oxidation reactions of allenes. Chemodivergent oxidative cascade reactions of enallenols were realized by switching between heterogeneous (Pd-AmP-MCF) and homogeneous (Pd(OAc)2) palladium catalysts. In separate cases, the heterogeneous catalyst Pd-AmP-MCF showed improved performance over its homogeneous counterpart, accompanied by high recyclability and no detectable metal leaching. Synthetically important cyclic skeletons such as cyclobutenols, furanes, oxaboroles, and fused γ-lactones/lactams were obtained via borylative or carbonylative carbocyclization reactions of enallenols in high yields and with excellent stereoselectivity.

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    Advances in Stereoselective Palladium(ΙΙ)-Catalyzed Oxidative Transformations of Allenes
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  • Disputation: 2020-05-29 13:00 Nordenskiöldsalen, Geovetenskapens hus, Stockholm
    Voytiv, Sofiya
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Sociologiska institutionen.
    Deterritorializing Conflict, Reterritorializing Boundaries: Diaspora and Conflict in the "Homeland"2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Ethnicized armed conflicts are usually studied in their territorial dimension and analyzed through the patterns of involvement of different direct and indirect actors. Mostly the focus lies on the multiple ways these direct and indirect actors affect the processes and outcomes of such conflicts. While direct actors mostly participate in the fighting itself, indirect ones can involve transnational advocacy organizations and diasporic groups. Diasporas in this perspective are usually considered to be either “peace-makers” or “peace-wreckers”. Less research has been done on the effects the ethnicized armed conflict in the “homeland” can have on diasporic communities.

    In this dissertation, I develop theoretical conceptualization of the intersection of armed conflict in the “homeland” and diaspora. I focus on a specific case of Ukrainian-Russian conflict and Ukrainian, Russian and conflict-generated diasporic groups in Sweden.

    I argue that the ethnicized armed conflict in the “homeland” can become deterritorialized. In other words, ideas, attitudes and ethnicized narratives of such conflicts can become detached from a certain geographical location and settle in the transnational space of interactions. Such conflict deterritorialization can in its turn trigger diasporization processes elsewhere. It can also mobilize the pre-existing diasporic organizations for “homeland”-related activism. If diasporic individuals and communities use the symbols, ideas and narratives of the conflict in the “homeland” in defining the Other, as well as their relationships and networks, another process – conflict reterritorialization – is at play. This process can subsequently shift group boundary making and maintenance processes.

    Together, the concepts of conflict deterritorialization and reterritorialization help explain the patterns and mechanisms of the armed conflict in its meaning dimension. In addition, such theoretical conceptualization enables the analysis of the effects the conflict might have in the diasporic setting, including the processes of politicization.

    Using the specific case of Ukrainian-Russian conflict (2014-ongoing) I analyze the collaboration networks of Ukrainian, Russian and conflict-generated organizations active in Sweden between 2013 and 2016 and interview Ukrainians and Russians from Ukraine living in Sweden. I show that both patterns of conflict deterritorialization and reterritorialization are present in this specific diasporic setting to different degrees.

    Study 1 theoretically conceptualizes conflict deterritorialization as a diasporization process using previous findings from different case studies. Study 2 investigates the mechanisms of diaspora politicization and the role of conflict-generated diasporas in facilitating these mechanisms. In Study 3 I find that during the most violent period of war in eastern Ukraine, the attitude towards the conflict might have become a leading factor for collaborations between diasporic organizations. And, finally, Study 4 explores the potentiality of armed conflict in the “homeland” to contribute to a shift in ethnic group boundary making processes in the diasporic setting.

    Taken together the four studies aim to shed light on the non-territorial meaning dimension of the ethnicized armed conflicts theoretically and empirically. Thus, the dissertation contributes to the development of the holistic understanding of war and diaspora while taking into account the importance of contexts, factors and conditions of the country of residence, the “homeland” and the transnational space.

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    Deterritorializing Conflict, Reterritorializing Boundaries: Diaspora and Conflict in the "Homeland"
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  • Disputation: 2020-05-30 13:00 hörsal 3, hus B, Stockholm
    Berlin, Marie
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Sociologiska institutionen.
    Out-of-Home Care and Educational Outcomes: Prevalence, Patterns and Consequences2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The aim of this thesis is to examine educational stratification in the context of out-of-home care (OHC; foster family care, residential care) and to place one of society’s most vulnerable groups in the fields of social stratification and family complexity research. About 5% of the Swedish population experience OHC during childhood or adolescence. OHC is not only a matter of protecting children and youth; it is also intended to improve future opportunities and compensate for adverse childhood factors. However, a vast body of international research, including Swedish studies, shows that a substantial proportion of young people from OHC have poor school performance and low educational attainment as adults. Furthermore, this is strongly associated with their high risk of other adverse outcomes in life. To date there are no signs of improvement in this regard, and the disadvantage of having a low education is increasing in today’s knowledge-based society.

    Many previous OHC studies have relied on small, local samples, and longitudinal data are often lacking. In this respect, Swedish researchers are well positioned to contribute to the field through research based on our high-quality population registers. The main data source in this thesis – the Child Welfare Intervention Register – covers half a century of OHC data. Based on these data, an overview of OHC prevalence in Sweden and patterns of educational outcomes are presented in the introductory chapter. The thesis further consists of five individual studies investigating different aspects of the transition through the educational system to adult life among children and youth from OHC. Two of the five studies focus on children who spent most of their childhood in OHC and for whom society has assumed a long-term commitment of parental responsibilities.

    The descriptive data show that patterns of poor educational outcomes in the OHC population have remained stable as long as they can be followed in the registers. Study I shows that youth who exited long-term care were disadvantaged as compared to youth without OHC experience, both in terms of educational attainment and regarding the strong association between poor school performance and other adverse outcomes in young adulthood. Up to 55% of their excess risks of later psychosocial problems were statistically attributable to dismal school performance. Study II shows that 54% of clients in substance-misuse treatment in the 1980s had been in OHC, half before their teen years and half as teenagers. In this group, OHC was associated with excess mortality during the 30-year follow-up from exit from treatment, with statistical significance mainly for females who had entered OHC before their teens. School failure was more common in the OHC population than for misuse clients without OHC experience, and was strongly associated with the excess mortality of females. Two Nordic comparative studies (Studies III and IV) show that the OHC population had a substantially higher risk of not completing upper-secondary education across countries, and that poor performance in primary school inflicted a greater risk in OHC youth of being NEET in young adulthood than for their peers without OHC experience. Study V shows that the intergenerational transmission of education was weak and inconsistent in the foster care setting, and that living in a highly educated foster family did not have a robust positive effect on foster children’s educational outcomes.

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  • Disputation: 2020-06-01 14:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Lübcke, Marvin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bifunctionalization of Small Organic Molecules Based on Fluorine Incorporation2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The dissertation work that is summarized in this thesis describes novel syntheses of organofluorine compounds with a broad coverage of different fluorine-containing motifs.

    Chapter 2.1 covers works on the exploration of new trifluoromethylthiolating reactions of diazocarbonyl compounds. A rhodium-catalyzed oxy-trifluoromethylthiolation reaction enabled the synthesis of densely functionalized carbonyl compounds. Different oxygen nucleophiles, for instance alcohols, ethers and acetals underwent this transformation.

    A zinc triflimide mediated three-component reaction established an arylation-trifluoromethylthiolation of diazocarbonyl compounds. In situ generation of triarylboranes was rendered most effective for the arylation event. Both procedures made use of the high reactivity of a recently developed electrophilic trifluoromethylthiolating reagent.

    The second chapter (2.2) is dedicated to the late-stage construction of trifluoromethyl motifs. By means of halide exchange, nucleophilic fluoride from a copper(I)-complex could be used to exchange bromide with fluoride in the α-position to carbonyl groups as well as in benzylic positions.

    The third chapter (2.3) covers the development of an enantioselective fluorocyclization reaction. In situ generated aryliodine(III)-fluoride species were used as organocatalysts. Through this oxidative olefin difunctionalization reaction, quaternary C-F stereogenic centers could be constructed with high enantiomeric excesses. DFT calculations enabled deeper understanding of the mechanism and the origin of stereoselectivity.

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  • Disputation: 2020-06-02 13:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Kapuscinski, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Following nanoparticle self-assembly in real-time: Small-angle X-ray scattering and quartz crystal microbalance study of self-assembling iron oxide nanocubes2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Self-assembly of nanoparticles is a widely used technique to produce nanostructured materials with crystallographic coherence on the atomic scale, i.e. mesocrystals, which can display useful collective properties. This thesis focusses on the underlying mechanism and dynamics of mesocrystal formation by using real-time techniques. Quartz-crystal microbalance with dissipation monitoring (QCM-D) as well as small-angle X-ray scattering (SAXS) in combination with optical microscopy were used to probe the temporal evolution of growing mesocrystals to elucidate the growth mechanism.

    Time-resolved small-angle X-ray scattering was used to probe the formation and how the structure and defects of the growing mesocrystals in levitating droplets evolve with time. Probing self-assembly of oleate-capped iron oxide nanocubes during evaporation-driven poor-solvent enrichment (EDPSE) showed that a low particle concentration in combination with a short nucleation period can generate large and well-ordered mesocrystals. Information on the formation and transformation of defects in mesocrystals were obtained by analysis of the temporal evolution of crystal strain. A transition from a rapidly increasing isotropic strain to a decreasing anisotropic strain towards the end of the growth stage was observed. The occurrence of anisotropic strain was assigned to the formation of stress-relieving dislocations in the crystal, which were induced by large internal stresses caused by superlattice contraction.

    Directed assembly of superparamagnetic iron oxide nanocubes, subjected to a weak magnetic field, produced one-dimensional mesocrystal fibers. Real-time SAXS as well as optical microscopy revealed a two-stage growth mechanism. The primary stage involved the growth of cuboidal mesocrystals by nanocube self-assembly. In a secondary stage, the cuboidal mesocrystals were assembled and aligned into fibers by the magnetic field. Evaluation of the magnetic dipole-dipole and van der Waals interactions showed that the dipolar forces arising between two nanocubes in a weak magnetic field are negligible compared to the van der Waals forces, but become the dominant force for larger mesocrystals, which drives the formation of fibers.

    QCM-D combined with optical microscopy provided simultaneously information on the rheological properties as well as on the mass of an adsorbed self-assembled layer of iron oxide nanocubes. We show that the iron oxide nanocubes rapidly assembled into an array with primarily viscous characteristics. This fluid-like behaviour can be assigned to a layer of solvent surrounding the nanocubes inside the assembly. Expulsion of the thin solvent layer from the assembled array is responsible for the increase in rigidity observed shortly after the beginning of self-assembly.

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    Following nanoparticle self-assembly in real-time: Small-angle X-ray scattering and quartz crystal microbalance study of self-assembling iron oxide nanocubes
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  • Disputation: 2020-06-04 13:00 sal G, Arrheniuslaboratorierna, Stockholm
    Westerman, Johan
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Sociologiska institutionen.
    Motives matter: Intrinsic motivation in work learning and labor market performance2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This dissertation examines the importance of individual work motivation for two crucial dimensions of inequality: work learning and labor market performance. The first dimension relates to learning activities at work, and the second to wage attainment and knowledge-oriented task assignment. While motivation is a broad concept, the empirical analyses focus on task involvement and the motivation to learn. Job mobility is further used to indicate a motivational strategy aimed at gaining new labor market experiences. 

    These kinds of motivation are related to individual variation in intrinsic motivation, representing: pure curiosity and a strive for competence in novel environments, a focus on personal development rather than on proving ability, satisfaction gained from feelings of competence and autonomy during task performance, and experience of complete absorption in activities of learning and mastery. 

    The connection between intrinsic motivation and extrinsic labor market rewards (such as wage attainment) is theorized to follow from: (a) a higher level of performance in learning activities at work, (b) consequent assignment to more productive work tasks, and (c) a rise in material rewards (wages) linked to this assignment.

    Variation in the extent to which intrinsic motivation can be elicited in individuals, and the extent to which intrinsic motivation is targeted toward performance related activities in the labor market, is thus expected to matter for patterns of inequality. Intrinsic motivation, as a productive factor shaping inequality, is expected to grow in importance in paralell with an increase in the labor market value of skills, and a decline in bureaucratic and closely monitored production organization. As a research agenda, the analysis of intrinsic motivation is thus crucial for understanding evolving patterns of conflict and inequality in contemporary societies.

    Study I analyzes the relationship between task involvement and wage attainment, and shows that task involvement is moderately associated with higher wages in two datasets: the Swedish Level-of-Living Survey (LNU) and the European Social Survey (ESS). Study II analyzes the relationship between repeated job mobility (a ‘new experiences strategy’) and work learning. Two datasets are used: LNU and the Swedish part of the Programme for the International Assessment of Adult Competencies (PIAAC). Results show that repeated job mobility is positively associated with several, but not all, kinds of learning activities. Study III analyzes the associations that motivation to learn shares with knowledge-oriented task assignment and wage attainment using PIAAC data for 17 European countries. Results show that the motivation to learn is strongly correlated with knowledge-oriented task assignment, and moderately correlated with wage attainment. These correlations are similar across distinct levels of numerical proficiency, and across labor market contexts.

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    Motives matter
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  • Disputation: 2020-06-05 10:00 sal G, Arrheniuslaboratorierna, Stockholm
    Baheru, Haymanot
    Stockholms universitet, Juridiska fakulteten, Juridiska institutionen.
    Hyressättning: Prisets reglering vid bostadshyra2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This thesis examines all historical and present day rent control models in the context of the Swedish housing market, both in form and substance. The systematic study of the historical development illustrates how varieties of rent control regimes, i.e. rent setting regulations, have been a permanent feature in the Swedish rental market since 1942 when a rent freezing act was introduced. In a long reregulation process between mid-1950s and mid-1980s, the rent control transformed from a matter of public law to private law. As the latter, legislative initiatives over said decades have effectively established an all-encompassing legislative infrastructure subjecting all residential tenancy contracts in the primary and the secondary housing market, but also hotel like lettings, to regulations which aim to establish a fair rent.

    The aim of the thesis is to determine what constitutes a fair rent in the Swedish residential tenancy law. The thesis finds that the concept of fair rent refers to a rent that does not exceed the applicable price ceiling – the objective price. Fairness of the subjectively applied rent is therefore assessed in relation to compliance with the permissible price. Divergence from the objective price is considered unfair if it contravenes the ceiling. The concept of fair rent derives its meaning from seven regulative models in the legal infrastructure. The main regulative models are found in the use value system – a system that is dominated by the collective bargaining regime where the Tenant's union enjoys a monopolylike position. The alternatives, contract models of different constructions, are found both within the scope of the use value system and outside. Within the co-operative rental sector, both an association model and the models of the use value-system can be found. The regulative models are not necessarily mutually exclusive. Several regulative models can be simultaneously applicable, whereby the same apartment can command several 'fair rents' − none less fair than the other. The arbitrary construction of fairness and its application on the rental market is the result of legislative initiatives, necessitated as reactive measures, and political compromises.  

  • Disputation: 2020-06-05 10:00 Stockholm
    Stenström, Anders
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Kriminologiska institutionen.
    The Plural Policing of Fraud: Power and the investigation of insurance and welfare fraud in Sweden2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    There is a vast literature on plural policing and the ways in which non-governmental actors now have and are assuming more responsibility for crime control. This literature argues that the connection between policing and the state is being eroded, questioned and sometimes abandoned in favour of networks in which the state acts as one actor among many others. This thesis examines the Swedish policing of insurance and welfare fraud via an analysis of the ways in which power is organized and articulated by actors in the private insurance industry, and at the Swedish Social Insurance Agency and police authority.

    The three articles included in the thesis contribute to a field that has received comparatively little attention, particularly in Sweden but also internationally. The existing literature has primarily been interested in the control of street-level criminality and the operations of uniformed security actors. Investigation practices in general and the plural policing of white-collar crime in particular have received far less attention. In Sweden, studies of policing are primarily state-centred, and the interactions between the police and other policing actors require further consideration. When examining insurance fraud, scholars have not considered the ways in which the insurance institution controls fraud; instead, this literature focuses on the characteristics of fraudsters. Thus the current thesis furthers our knowledge of a field of policing about which we currently know relatively little.

    The thesis takes as its general assumption the view that this form of policing is marked by a basic ambiguity between on the one hand being responsibilized and assuming responsibility for crime control, and on the other being responsible for other goals, such as promoting trust in, and the legitimacy and survival of the insurance institution. Existing research suggests that this ambiguity is resolved by simply denying compensation, adjusting premium levels, and cancelling policies or social benefits. My research shows that there is no Swedish exceptionalism in this sense.

    Based on a Foucauldian understanding of power, the thesis furthers our understanding of how the insurance institution is organized to tolerate fraud. The uncertainty between crime control and additional organizational goals is embedded in attempts to police the policing actors themselves, which is reflected in forces that make the policing of fraud a professional risk for the policing actors. The thesis argues that power relations provide opportunities to ensure that organizational goals are not endangered, while at the same time maintaining the public image that crime is being controlled. In contrast with existing research, the thesis shows that the law and the state – analytical categories that existing research, and particularly post-Foucauldian approaches, tend to reject or avoid – are critical to the plural policing of fraud. It is further suggested that scholars need to pay more attention to the way different technologies of power shape relationships between the actors involved in plural policing and their definitions of their own roles. In particular, scholars need to consider the role of the state and the legal framework in such arrangements. 

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    The Plural Policing of Fraud
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  • Disputation: 2020-06-05 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Oschmann, Michael
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium Catalysis in Directed C-H Bond Activation and Cycloisomerisation Reactions2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The main focus of this thesis concerns the development of Pd(II)-catalysed synthetic methodologies for the preparation of biologically active compounds.

    In the first part (paper I-III), unactivated C–H bonds of a cyclobutane derivative are selectively functionalised using a directing group starting from the feedstock compound verbenone (paper I). In the following part the development of an efficient transamidation protocol for the directing group removal is reported (paper II). Both procedures were then used in conjunction, for the synthesis of diverse C-3 arylated benzofuran-2-carboxylamides, in only 3 steps starting from benzofuran-2-carboxylic acid (paper III).

    The second part (paper IV-V) aimed to evaluate the catalytic efficiency of the heterogeneous catalyst Pd(II)-AmP-MCF in the intramolecular hydroamination of propargylic carbamates. The catalyst was able to promote the formation of various 1,3-oxazolidin-2-ones in high yields, at room temperature with low palladium loadings (paper IV). This investigation is followed by a mechanistic study of the Pd(II)-AmP-MCF catalyst’s deactivation process during a lactone formation, using X-ray absorption spectroscopy (paper V).

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    Palladium Catalysis in Directed C-H Bond Activation and Cycloisomerisation Reactions
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  • Disputation: 2020-06-05 13:00 Lilla hörsalen, Naturhistoriska riksmuseet, Stockholm
    Christidis, Maria
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för pedagogik och didaktik. The Swedish Red Cross University College.
    Integrated teaching for expanded vocational knowing: Studies in the Swedish upper secondary Health and social care program2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Integrated teaching is emphasized in Swedish upper secondary vocational education and training, for managing sociocultural and historical changes related to: a) increased demands on future competent health care workers, b) educational reforms, c) altered conditions for vocational teachers’ work, and d) vocational contextualization of teaching and learning content. However, national curricula from 1970, 1994, and 2011 recommend integrated teaching as a solution without any specific concretization of what integration could or should contribute with. Thus, the aim of this thesis was to explore the realization of integrated teaching and the vocational knowing made available by integration for students at the Swedish upper secondary Health and social care program, and partly for nursing students in higher education and training. The research questions attended to how integrated teaching is realized, and what vocational knowing is made available by integration.

    Theoretical point of departure was Cultural historical activity theory (CHAT), complemented with New literacy studies (NLS). The methodological framework included ethnographically inspired case studies, interviews, specifically semi-structured interviews and life-history interviews, and a systematic review. Research material was collected in 2012 and 2018. Analysis was performed with selected concepts from CHAT, and in one study also with concepts from NLS. In one study, i.e. the systematic review, GRADE CERQual was used for an assessment of confidence in the review findings.

    Study results showed that integrated teaching, regardless of composition and format, made available a vocational, a general, and an expanded vocational knowing. Also, vocational contextualization of school subjects was shown to be significant as an additional teaching and learning content and as mediational means between school and workplace.

    In conclusion, integrated teaching was shown to respond to the sociocultural and historical developments by making available for students an expanded vocational knowing. Also, vocational contextualization was shown to make possible for students learning knowing relevant for their future profession.

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    Integrated teaching for expanded vocational knowing
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  • Disputation: 2020-06-05 13:00
    Ramöller, Daniel
    Stockholms universitet, Humanistiska fakulteten, Filosofiska institutionen.
    On the possibility of limited weighing of lives2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This thesis discusses the possibility of limited moral trade-offs between different people’s welfare. In chapter 2, I introduce the two central limited trade-off conditions. First, according to minimal infinite superiority, significantly benefiting one person matters more than slightly benefiting each of any number of better-off people. Second, according to minimal finite superiority, significantly benefiting many people matters more than slightly benefiting one person. I consider both axiological and deontic interpretations of these conditions. However, I explain why none of the simple classic moral principles—the simple total and the maximin principles—satisfy both conditions. Furthermore, in chapter 3, I strengthen several proved impossibility results according to which no moral theory satisfies weak interpretations of these central trade-off conditions and several other seemingly plausible minimal conditions. I show that giving up structural axiological and deontic conditions is not a satisfactory solution to these paradoxes. In chapter 4, I discuss the modification of a background assumption of these impossibility results on the measurement of welfare. I show that, given a modification that allows for lexicographically ordered welfare components, a total principle can satisfy all the conditions of the impossibility results. However, I argue that such a modification is not entirely satisfactory because it does not apply in certain instances of the paradoxes. In chapter 5, I discuss a further weakening of minimal infinite superiority. However, I show that a suggested possibility result based on this modification is not valid and that further moral conditions, such as minimal finite superiority, need to be modified. Moreover, I argue that these modified conditions and the principle suggested in the possibility proof—a minimax complaint principle—do not capture the basic idea of the two central limited trade-off conditions sufficiently well. In chapter 6, I argue that other principles suggested for the task—the total claim principles—share the same fate as the simple total principles or the minimax complaint principle. In chapter 7, I propose new principles that take their structural roots from voting theory. I show that, in contrast to the other principles discussed, these principles give plausible verdicts where the other principles failed. Finally, in chapter 8, I consider possible objections levelled against this proposal, and I suggest solutions and avenues for future research.

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    On the possibility of limited weighing of lives
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  • Disputation: 2020-06-05 14:00 Nordenskiöldsalen, Geovetenskapens hus, Stockholm
    Foltyn, Richard
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Nationalekonomiska institutionen.
    Essays in Macroeconomics and Household Finance2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Experience-based Learning, Stock Market Participation and Portfolio Choice

    Recent evidence suggests that lifetime experiences play an important role in determining households' investment choices. I incorporate these findings and the fact that household portfolios are underdiversified into an otherwise standard life-cycle model and examine to what extent they can help resolve long-standing puzzles in the literature regarding stock market participation and the fraction of financial wealth invested in risky assets. I show that experience-based learning about returns creates a positive correlation between a household's position in the wealth distribution and its optimism about future returns. The wealthy consequently increase their investment in risky assets, while participation is limited among poor households. I find that in a reasonably calibrated quantitative model, this mechanism is able to close approximately half of the gap between the participation rates observed in the data and the predictions from standard models.

    Health Dynamics and Heterogeneous Life Expectancies

    In this paper, we provide improved estimates for age-dependent health transitions and survival probabilities for different subsamples of the US population. The estimated yearly transition matrices can be used in any life-cycle model where health and survival dynamics are of interest. The results show substantial heterogeneity in life expectancy in the population. For a 70-year-old man in excellent health, the probability of reaching his 80th birthday is around 75%, while the corresponding probability for a man in poor health is just below 40%.

    Subjective Life Expectancies, Time Preference Heterogeneity and Wealth Inequality

    Time preference heterogeneity is one of the potential sources of wealth inequality, but preferences are difficult to measure and quantify. In this paper, we investigate one source of time preference heterogeneity: heterogeneity in life expectancy. We document a systematic bias in subjective survival beliefs within cohorts that exacerbates the heterogeneity found in the population: individuals with a low survival probability relative to their peers underestimate their life expectancies, while individuals with a high survival probability overestimate theirs. We introduce survival heterogeneity into an otherwise standard overlapping-generations model and let survival probabilities and beliefs evolve stochastically according to a health and death process estimated from micro data. We find strong effects of life expectancy heterogeneity on within-cohort wealth inequality, but small effects on economy-wide wealth inequality.

    On the Redistributive Effects of Government Bailouts in the Mortgage Market

    In this paper we study the aggregate and distributional consequences of government bailout guarantees in the US mortgage market. We construct a model with aggregate risk in which competitive financial intermediaries issue mortgages to households that can default on their debt. Default probabilities are priced into mortgage interest rates unless a government bailout guarantee makes the lenders whole even in economic downturns in which foreclosure rates surge. We use the model to assess the extent to which bailout guarantees lead to excessive mortgage lending, household leverage and foreclosures in episodes of housing crises, as well as excess volatility in house prices in severe recessions.

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    Essays in Macroeconomics and Household Finance
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  • Disputation: 2020-06-08 13:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Rathore, Sorbhi
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Structural characterisation of mitochondrial macromolecular complexes using cryo-EM: Mitoribosome biogenesis and respiratory chain supercomplex2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Mitochondria, popularly known as powerhouse of the cell, contain specialised mitoribosomes that synthesise essential membrane proteins. These essential proteins are required to form enzyme complexes, which carry out the process of oxidative phosphorylation (OXPHOS). OXPHOS is carried out by five enzyme complexes (Complex I-V), out of which complex I, III and IV pump protons during electron transfer from NADH to Oand complex V uses the generated proton gradient to synthesise ATP. Cryo-EM, as a revolutionary technique in structural biology made it possible to determine the structures of mitoribosome assembly intermediates and respiratory chain supercomplexes. These structures have allowed us to investigate the mitoribosome biogenesis pathway in human and yeast and to gain deeper insights into the architecture of supercomplexes. In the first area of research, using cryo-EM we were for the first time able to capture mitoribosomes in different late stages of assembly and to determine their high-resolution structures with novel factors bound. Investigation of this process was previously unreachable due to lack of techniques to trap these mitoribosome complexes in different states of assembly. The structures of these assembly intermediates establish the role of assembly factors such as MALSU1, LOR8F8, mt-ACP, MTG1 and mitoribosomal proteins (MRPs) in mitoribosome biogenesis and to ensure proper maturation of each subunit, reflecting their role in regulating translation. Furthermore, genetic deletion studies of MTG1 and uL16m in yeast show the importance of transiently acting factors and MRPs in the mitoribosome assembly process and their effects on translation. The assembly pathway of mitoribosomes is critical for protein synthesis since defects in the translation process causes inherited human pathologies. Therefore, elucidation of mitoribosomal biogenesis pathways may also contribute to the development of potential new therapeutic opportunities. In the second research area, structures of the respiratory chain supercomplex from yeast were determined. These are the first near-atomic resolution structures that show organization of complex III and complex IV into two distinct classes that form higher order assemblies (III2IV1and III2IV2). Moreover, the architecture of the supercomplex structures differs from the previously determined respirasomes (I1III2IV1) structures in mammals. We obtained a near-atomic resolution structure of the yeast complex IV, revealed core protein-protein and protein-lipid interactions that hold the supercomplex together. Moreover we found novel subunits required for supercomplex formation in S. cerevisiae. The last part of my study focuses on cryo-EM sample method development where we could successfully demonstrate the usefulness of a simple pressure-assisted sample preparation method for microcrystals, proteins and mitochondria. Our findings show great resolution improvements of selected area electron diffraction patterns of microcrystals, a significant reduction in needed sample concentration for single particle studies and an enrichment of gold nano-particles for tomographic studies.

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    Structural characterisation of mitochondrial macromolecular complexes using cryo-EM
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  • Disputation: 2020-06-09 10:00 sal G, Arrheniuslaboratorierna, Stockholm
    Blomqvist, Niklas
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Nationalekonomiska institutionen.
    Essays on Labor Economics: The Role of Government in Labor Supply Choices2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    "Right to Work Full-time" Policies and Involuntary Part-time Employment

    This paper investigates the effect of right to full-time policies implemented to decrease involuntary part-time work for public care workers employed by Swedish municipalities. Taking advantage of a staggered decision process, these policies are evaluated using a difference-in-differences approach. Results show that involuntary part-time employment is real and significant, with 10% of part-time employed workers choosing full-time when given the opportunity. The effect mainly comes from a decrease in contracts of <75% of full-time and an increase in contracts of 80% of full-time and above. Further results from the full-time policies show that being more flexible in the choice of hours worked is popular among workers, indicated by an increase in tenure and reduced turnover in municipalities that offer more flexibility in the choice of hours worked.

    Hours Constraints and Tax Elasticity Estimates - Evidence from Swedish Public Care Workers

    There is a concern that tax elasticity estimates may be downward biased in the presence of optimization frictions for workers. So far, there is limited evidence on the nature of these optimization frictions. This paper provides new insight into one part of the optimization frictions black box, namely hours constraints. Using unique and newly collected data, I exploit a staggered implementation of a policy that gave some public care workers the opportunity to choose their preferred hours of work. Taking advantage of this policy, I estimate differences in tax elasticities between constrained and unconstrained public care workers by comparing bunching at a large tax kink in the Swedish tax system. The empirical evidence points to the conclusion that hours constraints do not affect tax elasticity estimates.

    Restricting Residence Permits - Short-Run Evidence from a Swedish Reform

    In June 2016, the Swedish parliament decided to restrict the granting of permanent residence permits for asylum seekers in Sweden. The new status quo for a refugee is a temporary rather than a permanent residence permit. In a first evaluation of this reform we use a Regression discontinuity analysis in which we follow refugees, aged 25-65, over their first years after arrival. Our main results show that a temporary residence permit increases the probability of working and enrolling in regular education.

    Mom and Dad Got Jobs: Natural Resources, Economic Activity, and Infant Health

    The impact of local economic shocks, such as the discovery and exploitation of natural resources, on labor markets and health is not well understood. Both positive and negative effects have been documented in the literature. In this paper, we show that the phase before active resource extraction begins directly affects the local economy. This implies that previous estimates – typically based on designs exploiting differences before and after the active phase of extraction begins - may have understated the actual effect of natural resource extraction on outcomes of interest. Using rich data from Sweden combined with differences in the timing and location of mineral exploitation permits, we find a positive impact on female and male employment and earnings and a negative effect on housing prices. Children’s health outcomes are also negatively affected, an effect likely driven by the increase in local economic activity rather than extraction-related externalities.

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    Essays on Labor Economics
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  • Disputation: 2020-06-09 13:15 sal FB42, AlbaNova universitetscentrum, Stockholm
    Mahyaeh, Iman
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Study of the phase diagram of Zn symmetric chains2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In this thesis we study the phase diagrams of Zn symmetric chains. We start with investigating the topological phases of the Kitaev chain, a Z2 symmetric model, with long range couplings and a phase gradient. Then we go beyond the free fermion classification of topological phases and consider the effect of interactions by studying the Kitaev-Hubbard chain, incorporating a density-density interaction. Next we move on to the Z3 symmetric models and present a frustration free model with an exact three-fold degenerate ground state. In the end we present the phase diagram of a hopping model of Z3 Fock parafermions, the generalization of polarized Dirac fermions which could host at most two particles per site. The model has a pairwise hopping which is forbidden for fermions. In our studies we use analytical methods like the Lieb-Schultz-Mattis method, bosonization and conformal field theory, as well as numerical ones like exact diagonalization and the density matrix renormalization group.

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  • Disputation: 2020-06-10 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Gestin, Maxime
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    PepFect14, a Versatile Cell-Penetrating Peptide2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Cell-penetrating peptides have been discovered almost three decades ago and there are, nowadays, thousands of available sequences. They offer multiple applications in the field of drug delivery as they are able to carry therapeutic macromolecules across the plasma membrane. Throughout the years, new sequences have been developed and designed to achieve new applications such as specificity for certain kinds of cargoes, intrinsic therapeutic effects and targeted delivery.

    In this thesis, we focused on a single most promising cell-penetrating peptide named PepFect14 and aimed at reaching a better understanding of the factors involved in the cellular uptake through paper I and paper II. Notably, in paper I we screened a library of small molecule drugs that influences signaling pathways and discovered that three drugs had an unreported influence on endocytosis. In paper II, After performing an RNA sequencing on cells treated with PepFect14, we demonstrated the involvement of autophagy in the intracellular trafficking of the cell-penetrating peptide. A second aim of this thesis, covered in paper III and paper IV, was to discover new applications for PepFect14 in order to broaden its potential. In paper III, we successfully used PepFect14 to mediate the intracellular delivery of heat shock protein 70kDa. This was the first protein delivery assisted by PepFect14. In paper IV, PepFect14 was covalently fused to mtCPP1, a cell-penetrating peptide that targets mitochondria and reduce the level of reactive oxygen species. The constructs showed the ability to keep the properties of both peptides and achieved a mitochondria-targeted antisense therapy.

    Overall, this thesis summarizes our effort to develop and bring to their full potential already existing cell-penetrating peptides instead of developing new sequences for each new application.

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    PepFect14, a Versatile Cell-Penetrating Peptide
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  • Disputation: 2020-06-10 13:00 sal 14, hus 5, Kräftriket, Stockholm
    Muhinyuza, Stanislas
    Stockholms universitet, Naturvetenskapliga fakulteten, Matematiska institutionen.
    Statistical Inference of Tangency Portfolio in Small and Large Dimension2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis considers statistical test theory in portfolio theory. It analyses the asymptotic behavior of the considered tests in the high-dimensional setting, meaning k/n c ∈ (0, ∞) as n → ∞, where k and n are portfolio size and sample size, respectively. It also considers the high-dimensional asymptotic of the product of components involved in the computation of the optimal portfolio. The thesis comprises four manuscripts:

    Paper I is concerned with the test on the location of the tangency portfolio on the set of feasible portfolios. Considering the independent and normally multivariate asset returns, we propose a finite-sample test on the mean-variance efficiency of the tangency portfolio (TP). We derive the distribution of the proposed test statistic under both the null and alternative hypotheses, using which we assess the power of the test and construct a confidence interval. The out-of-sample performance of the portfolio determined by the proposed test is conducted and through an extensive simulation study, we show the robustness of the developed test towards the violation of the normality assumptions. We also apply the developed test to real data in the empirical study.

    Paper II extends the results of paper I. It is concerned with the study of the asymptotic distributions of the test on the existence of efficient frontier (EF) and the efficiency of the tangency portfolio in the mean-variance space in the high-dimension setting under both the null and alternative hypotheses. Finite-sample performance and robustness of the proposed tests are studied through an extensive simulation study.

    In paper III, we study the distributional properties of the TP weights under the assumption of normally distributed logarithmic returns. The distribution of the weights of the TP is given under the form of a stochastic representation (SR). Using the derived SR we deliver the asymptotic distribution of the TP weights under a high-dimensional asymptotic regime. Besides, we consider tests about the elements of the TP weights and derive the asymptotic distribution of the test statistic under the null and alternative hypotheses. In a simulation study, we compare the power function of the high-dimensional asymptotic and the exact tests. Moreover, in an empirical study, we apply the developed theory in analysing the TP weights in a portfolio made of stocks from the S&P 500 index.

    In paper IV, we derive a stochastic representation of the product of a singular Wishart matrix and a singular Gaussian vector. We then use the derived SR in the obtention of the characteristic function of that product and in proving the asymptotic normality under the double asymptotic regime. The performance of the obtained asymptotic is shown in the simulation study.

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    Statistical Inference of Tangency Portfolio in Small and Large Dimension
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  • Disputation: 2020-06-11 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Stephan, Katharina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Biogenesis of the bc1 complex in mitochondria2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Mitochondria perform a variety of tasks, but the function they are most prominent for is the energy conversion to form ATP, the universal energy equivalent of the cell. The majority of this ATP is created by the oxidative phosphorylation system, consisting of the respiratory chain and the ATP synthase. These elaborate machineries channel electrons through the respiratory complexes and thereby generate an electrochemical gradient across the inner mitochondrial membrane. This, so called proton motive force, is in turn utilized by the ATP Synthase to produce ATP.

    A particularity of the oxidative phosphorylation complexes is that their subunits are derived from two genetic sources. As a result, and the fact that the respiratory chain complexes contain redox cofactors, the biogenesis of these enzymes is challenging and involves multiple, highly coordinated and regulated assembly steps. For the obligate homodimeric bc1 complex, a handful of assembly factors are known and its assembly can be divided into distinct assembly intermediates. In this work we provided insights into the maturation of the catalytic subunit cytochrome b. We revealed that the insertion of the redox active heme b groups is sequential and that it depends on the interaction with the early assembly factor Cbp4. With successful insertion of both heme bs, the binding of the structural subunit Qcr7 is necessary for stabilization and further assembly.

    Furthermore, we were able to delineate the dimerization event in detail. We could establish that the interaction of the two matrix subunits, Cor1 and Cor2, with the bc1 complex assembly intermediate II, as well as the dissociation of Cbp4, are the triggering point for dimerization.

    In our subsequent work we investigated the roles of the fairly uncharacterized assembly factor Bca1 and its interplay with the structural subunit Qcr7. We could demonstrate that Bca1 interacts early and transiently during assembly and is an important factor for efficient assembly. Additionally, we could show that Qcr7 is not only a structural subunit but also serves as an assembly checkpoint for the maturation of the bc1 complex.

    With our work we could illustrate the necessity for basic biochemical research within the model organism yeast, as the fundamental molecular mechanisms are well conserved. This is exemplified by our work on UQCC3, the human orthologue of the bc1 complex assembly factor Cbp4.

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    Biogenesis of the bc1 complex in mitochondria
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  • Disputation: 2020-06-11 13:00 Auditorium (215), Manne Siegbahnhusen, Stockholm
    Wahlin, Claes
    Stockholms universitet, Humanistiska fakulteten, Institutionen för kultur och estetik.
    Att anlita översättning: Chaucer, Dryden, Arnold, Pound2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This thesis – Translation employed – Chaucer, Dryden, Arnold, Pound – investigates the motives and circumstances of translations of four authors/translators: Geoffrey Chaucer, John Dryden, Matthew Arnold and Ezra Pound. All four employ translation for purposes that exceed linguistically faithful transmission of a source text.

    My point of departure is the theoretical framework known as translation studies, which places critical focus less on the semantic transfer of texts than on a translator’s motivation for choosing a specific text to translate and the projected function of that text in a target literary system.

    In the first section I contrast the Chaucer’s translation of Boethius’ De consolatione philosophiae, with Chaucer’s Troilus and Criseyde. Chaucer’s Boece is a rather literal translation of its predecessor, linguistically faithful, though with the target text expanded and commented. In Troilus and Criseyde, by contrast, Chaucer semi-hides his sources, among them Petrarch. Chaucer’s Boece follows a primary mode of translation. By silently adapting Petrarch’s text, Troilus and Criseyde is translation in the secondary mode.

    Dryden updated Chaucer (as founder of English poetry and language), and I recount here the political, social and cultural climate in a time when social upheaval rendered reading suspicious and the printed words itself a danger to public order. In this climate, the Royal Society, as well as some individual authors, set out to develop a pure and perfect language. I examine in particular Dryden’s translation of the prologue to one of Chaucer’s Canterbury tales and discuss how Dryden’s notion of metempsychosis, and his idea that poets through history can be thought of as a long chain of father-son relations, legitimised his domestication of the source text.

    In the mid-19th Century, Arnold’s critique of Francis Newman’s translation of Homer’s The Iliad reflects a Victorian view of the Greek classics, as well as substantial ambitions for Homer. I sketch this background and compare Newman’s and Arnold’s distinct prescriptions for an English Homer. I argue that Newman’s main purpose was to make Homer known to the uneducated, but interested public, whereas Arnold’s vision was for a domesticated Homer, who functioned as an ethical and cultural beacon and nationalistic ideal.

    In the 20th century Pound’s translation of a sirventes by the occitan troubadour Bertran de Born, shows how Pound developed his own language partly by making his predecessors seem contemporaneous. The aim of this chapter is not only to rehearse this, but also to downplay the supposedly radically new in Pound’s translation practice. Here I compare Bertran de Born’s poems, as translated by Victorian John F. Rowbotham with the two translations made by Pound. The difference between Rowbotham’s domesticated version and Pound’s, shows how Pound in his first, so-called pedagogical translation, keeps close to the source text, and in his second, poetical translation, employs the Born’s work for his poetical ambitions. Pound had at least two literary objectives for the translations of Bertran de Born: one concerning his own poetic idiom, and the other his ambition to reinvigorate the contemporary literary culture. Pound sought to blend the past with the present in his own poetry, a purpose that he realises in the poem “Sestina: Altaforte”.

    Certain translation strategies recur, such as the idea of metempsychosis in Dryden and Pound, and the need to appropriate the target text in full, particularly for Chaucer and Pound. Political considerations have bearing in the case of Chaucer (the church), and are also prominent for Dryden and Arnold. Pound by contrast is almost exclusively interested in aesthetics. All four authors/translators employ translation for purposes that have less to do with an historical understanding of an original, source text than their own contemporary use of a target text.

     

     

  • Disputation: 2020-06-11 13:00 Endast online: https://stockholmuniversity.zoom.us/j/5073530222 (inte i Lilla hörsalen, NOD-huset, Kista)
    Aspling, Fredrik
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Unleashing Animal-Computer Interaction: A Theoretical Investigation of the “I” in ACI2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Non-human animals have had a long co-existence and relationship with human culture and society, and we interact with them in a number of ways, and for various reasons. Their involvement in technology can be traced back more than half a century, initially restricted to scientific contexts, for example, for the study of animal behavior, cognition, or language learning abilities. The advancement and growing ubiquity of technology has extended their interactions with technology beyond scientific settings to other domains and everyday contexts, and for a broader set of reasons. This development is also driven by the emerging research area of animal-computer interaction (ACI), in which scholars of human-computer interaction (HCI) are starting to explore the possibilities of designing interactive technology for and with animals. This requires engagement with the difficult task of understanding this new set of actors and the types of interactions and functionality they possibly would like to have with computing. This is a challenge even when it comes to humans, but the challenge escalates when considering other animals, and presents even more challenges. Animals live different lives to us, and include a broad and diverse category of species, with different ways of experiencing and being in the world, and we have difficulty understanding each other due to these interspecies differences. The shift from human to animal interaction is far from straightforward.

    This new and embryonic situation contests traditional notions of what a “user” is and can be, and how both digital technologies and other species, are being used. Consequently, it also challenges previous theoretical foundations and methods for understanding and designing user-computer interactions. The latter has received special attention, where user-centered design approaches and methods from the field of HCI and interaction design (IxD) has become a natural point of departure. As a complement, ACI needs a bolder and more creative way of progressing when it comes to building a theoretical framework to account for these new forms of interaction. There is a need to extend our thinking and the conventional ways of doing research and design, and to preserve curiosity and theoretical and methodological openness. As an alternative to many other design approaches, this thesis advocates the theoretical investigation of the “I” in ACI, aiming to extend the conventional notion of how interaction is conceptualized, a topic that has suffered from negligence. Drawing on ethnomethodological and ethnographic fieldwork – covering a maximum variation of extreme and deviant of cases – this thesis investigates the boundaries of the field and different theoretical perspectives and empirical insights, in order to increase our understanding of the emerging dynamics of multispecies-computer interactions, and also how these insights can excite the imagination and generate topics for zoocentric design and computing.

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    Unleashing Animal-Computer Interaction
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  • Disputation: 2020-06-12 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Menon, Preeti
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    The amyloid-β precursor protein (APP) and its adaptor protein Fe65: Two key players in Alzheimer’s disease2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Alzheimer’s disease (AD) is a neurodegenerative disease characterized by the abnormal accumulation and aggregation of amyloid beta (Aβ) peptides within the brain. Generation of Aβ occur when the amyloid-beta precursor protein (APP) is proteolytically processed by β- and then γ-secretase in the amyloidogenic pathway. However, if APP instead is cleaved by α- and γ-secretase in the non-amyloidogenic pathway, Aβ formation is prevented and neuroprotective sAPPα is generated. In addition to these canonical processing pathways, APP can also be cleaved along non-canonical pathways by Δ, η, caspase or Meprinβ, resulting in numerous fragments that have different functional properties. The trafficking and processing of APP is a complex process and can be regulated by the adaptor protein Fe65. Following γ-secretase mediated cleavage of APP, the intracellular domain of APP and Fe65 can together translocate into the nucleus and regulate nuclear signaling. However, the exact mechanisms of how APP processing and APP/Fe65 nuclear signaling are regulated is still unclear.  

    The aim of this thesis was to study different factors that may influence the regulation of APP processing and Fe65 nuclear localization. We found that phosphorylation of APP at Ser675 alters APP processing resulting in reduced levels of sAPPα and total sAPP, without affecting the plasma membrane level of APP. We could further observe an increased level of a slower migrating C99 like CTF, which was not generated by β-secretase cleavage of APP as there was no expression of BACE1 in the cell model used. Instead, generation of this CTF was blocked upon Meprinβ siRNA knockdown. Taken together these findings suggest that APP-Ser675 phosphorylation promotes Meprinβ processing of APP. In another study, we found that mutation of Ser228 at the Fe65 N-terminal dramatically increased the interaction between Fe65 and full-length APP. Moreover, this enhanced interaction resulted in decreased levels of non-amyloidogenic processing of APP and thus neuroprotective sAPPα. This suggest that the level of Fe65-APP interaction is important in regulating APP processing. Therefore, we also wanted to elucidate more about how the adaptor protein Fe65 is regulated. We found that Fe65 is likely phosphorylated on several residues in the N-terminus and that these phosphorylated forms preferentially localized in the cytoplasm. In addition, we could show that the nuclear level and nuclear/cytoplasmic ratio of Fe65 was decreased upon mutation of Fe65-Ser228 to glutamic acid, mimicking phosphorylation. Taken together this suggest that phosphorylation of Ser228 together with other residues in the N-terminus of Fe65 negatively regulate the Fe65 nuclear localization. In a third study, we could also show that the Fe65 PTB2 domain, rather than the WW domain, plays an important role in localizing Fe65 to the nucleus. Lastly, using different inhibitors, we found that blocking α-secretase processing decrease the Fe65 nuclear localization to the same extent as γ-secretase inhibition in both undifferentiated and RA or PMA differentiated cells. This suggest that α-secretase processing of APP or other Fe65 interacting transmembrane proteins play a more important role in regulation of Fe65 nuclear localization than previously thought. Interestingly, while ADAM10 was the most important α-secretase mediating this effect in undifferentiated cells, other α-secretases, likely ADAM17, played a more important role in RA or PMA differentiated neuroblastoma cells.

    In summary, the results obtained in this thesis have increased the understanding of APP processing and how the adaptor protein Fe65 may act as a molecular switch altering APP cleavage.

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    The amyloid-β precursor protein (APP) and its adaptor protein Fe65
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  • Disputation: 2020-06-12 10:00 Vivi Täckholmsalen (Q-salen), Stockholm
    Scher, Sebastian
    Stockholms universitet, Naturvetenskapliga fakulteten, Meteorologiska institutionen (MISU).
    Artificial intelligence in weather and climate prediction: Learning atmospheric dynamics2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Weather and climate prediction is dominated by high dimensionality, interactions on many different spatial and temporal scales and chaotic dynamics. This makes many problems in the field quite complex ones, and also state-of-the-art numerical models are - despite their immense computational costs - not sufficient for many applications. Therefore, it is appealing to use emerging new technologies such as artificial intelligence to tackle these problems.

    We show that it is possible to use deep neural networks to emulate the full dynamics of a strongly simplified general circulation model, providing both good forecasts of the model state several days ahead as well as stable long-term climate timeseries. This method partly also works on more complex and realistic models, but only for forecasting the model's weather several days ahead, not for creating climate runs. It is sufficient to use 50-100 years of data for training the networks. The same neural network method can be combined with singular value decomposition from numerical ensemble weather forecasting in order to generate probabilistic ensemble forecasts with the neural networks.

    On a more fundamental level, we show that in a simple dynamical systems setting there seem to be limitations in the ability of feed-forward neural networks to generalize to new regions of the system. This is caused by different parts of the network learning to model different parts of the system. Contradictory, for another simple dynamical system this is shown not to be an issue, raising doubts on the usefulness of results from simple models in the context of more complex ones. Additionally, we show that neural networks are to some extent able to “learn” the influence of slowly changing external forcings on the dynamics of the system, but only given broad enough forcing regimes.

    Finally, we present a method to complement operational weather forecasts. Given the initial fields and the error of past weather forecasts, a neural network is used to predict the uncertainty in new forecasts, given only the initial field of the new forecast.

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    Artificial intelligence in weather and climate prediction: Learning atmospheric dynamics
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  • Disputation: 2020-06-12 10:00 Sal P216, NPQ-huset, Stockholm
    Hurtig, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut.
    Divisive structures: Two billions years of biofilament evolution2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Our understanding of the functional and regulatory complexity that existed in the eukaryotic progenitor is poor, and investigations have been hindered by our nebulous understanding of where eukaryotes stem from. Recently discovered archaeal lineages with hitherto unseen homology to eukaryotic systems suggest archaea can further our understanding of the eukaryotic cell’s ancestry. However, much of archaeal biology remains largely unexplored. Two eukaryotic systems with archaeal homologues, namely the actin and ESCRT-III protein filament systems, are essential for diverse processes in eukaryotic biology. In this thesis, we show that an archaeal homologue of ESCRT-III divides the cell under proteasomal regulation, a regulatory mechanism central to eukaryotic cell cycle regulation. Additionally, we show how predicted putative profilin and gelsolin homologues regulate the postulated proto-cytoskeleton of Asgard archaea. In investigating the function and regulation of these archaeal systems we demonstrate compelling parallels between archaeal and eukaryotic regulatory strategies which stresses the close evolutionary relationship that exists between these two domains.

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    Divisive structures
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  • Disputation: 2020-06-12 13:00 rum 2427 på Institutionen för pedagogik och didaktik, Stockholm
    Malm, Tobias
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för pedagogik och didaktik.
    Konsten att hålla ihop: Om lärande och organisering i rockband2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Rock bands are foundational for modern day music life. These small groups provide well-being and self-fulfillment to its members, as well as fuel for the cultural life and the increasingly highlighted creative industries. Rock bands, however, are particularly difficult to organize. Bands face a range of challenges in keeping together and developing as a group.

    The aim of this doctoral thesis is to develop knowledge on rock band formation and development over time. Based in the discipline of education, the thesis mainly contributes to the fields of organization studies, social theories of learning, and music and cultural life research.

    The thesis uses the theory of situated learning to explore rock band formation and development. The methodology is qualitative and ethnographic, and the research design builds on three studies: an interview study with three rock bands and two case studies. All five bands are Swedish and have found different degrees of success and popularity.

    The thesis investigates band activities and courses of events, band members’ identities, and challenges faced. The findings indicate that a rock band’s activities shift between a production mode – i.e. highly productive times associated with public performances, record releases and marketing, and behind the scenes processes of creating, recording and planning – and a contrasting less active hibernation mode without bigger public projects or goals. The amount of time spent in production mode depends on the band’s degree of “membership” in the music industry. Moreover, a band member forms and actualizes identities of colleague, creator, entrepreneur, friend, hobbyist and professional, in differing combinations, situations and modes. Furthermore, the members’ most significant challenges relate to identity dilemmas.

    Based on these findings, the thesis formulates a model for a rock band’s learning trajectory and argues that a band may develop as it approaches, or becomes a more central member in, the music industry. This development demands increased public success and organizational ability: the band members’ ability to form business-oriented practices, to participate uniformly in an overarching community of practice, and to be flexible as they must identify with, and ascribe meaning to, a variety of activities in different and sometimes contradictory ways.

    The thesis concludes that the challenges of persistence as a rock band or similar group relates chiefly to group member difficulties in identifying with different activities and situations that are necessary to sustain and develop as a collective. Eventually, individual members tend to handle the experience of uncertainty and ambivalence by holding on to one singular identity, which may prevent group development, foster intra- and interpersonal tensions, and ultimately can lead to significant conflicts and/or a band’s breakup.

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    Konsten att hålla ihop
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  • Disputation: 2020-06-12 13:00 sal FB52, AlbaNova universitetscentrum, Stockholm
    Späh, Alexander
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    X-Ray Investigations of the Liquid-Liquid Critical Point Hypothesis in Supercooled Water2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis presents experimental x-ray scattering studies on supercooled liquid water. A liquid-liquid transition between two structurally distinct configurations has been found in deeply supercooled water, indicating the existence of a liquid- liquid critical point. The experiments were performed at large-scale x-ray facilities, mostly using free electron x-ray lasers including PAL-XFEL in Korea, SACLA in Japan, LCLS in the USA, SwissFEL in Switzerland and European XFEL in Germany, as well as using synchrotrons including APS in the USA, PETRA III in Germany and ESRF in France.

    Two conceptually different experimental approaches have been used to investigate the metastable phase of supercooled water. The first approach is based on rapid evaporative cooling of μm-sized water droplets that are injected into a vacuum chamber. Using this method, supercooled liquid water samples with temperatures down to approximately 227 K have been obtained, with the lowest temperature limited by homogeneous ice crystallization occurring after just a few milliseconds. In a second approach, structurally arrested high-pressure and therefore high-density amorphous ice samples are heated by an ultrafast infrared laser pulse. The fast heating melts the ice into a corresponding high-density liquid. At short time delays between the heating laser pulse and a subsequent x-ray probe pulse, the supercooled liquefied sample still experiences the high internal pressure of the initial state. At longer pump-probe delay times the supercooled water sample releases its internal pressure through structural relaxation. Hence, varying the pump-probe delay allows to probe the sample at different pressures.

    Together, these two approaches have been used to access a region within the metastable phase diagram of supercooled water that has previously been inaccessible. Using elastic x-ray scattering measurements as a structural probe of the liquid, we identified the existence of a liquid-liquid phase transition in deeply supercooled water. The observed phase transition is interpreted as the transition between a high-density and a low-density liquid phase. At high pressure this phase transition is discontinuous or first-order like, featuring a characteristic double-peak feature in the observed x-ray scattering intensity of the first diffraction maxima. At ambient pressure, however, we observe a continuous shift of the first diffraction maxima that is consistent with a continuous or second-order phase transition between the two liquids. Further evidence of a continuous phase transition at ambient pressure is seen in the temperature dependent maxima of the measured correlation length, isothermal compressibility and heat capacity, which indicate the existence of a Widom line.

    In summary, the experiments support the existence of a liquid-liquid critical point where the experimentally observed Widom line and phase coexistence line would both meet. The main result, however, is the first experimental observation of a liquid-liquid transition within a pure liquid.

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    X-Ray Investigations of the Liquid-Liquid Critical Point Hypothesis in Supercooled Water
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  • Disputation: 2020-06-12 13:00 sal G, Arrheniuslaboratorierna, Stockholm
    Almén, Daniel
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Nationalekonomiska institutionen.
    Societal Impacts of Modern Conscription: Human Capital, Social Capital and Criminal Behaviour2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Opportunity Costs and Conscription: An Unintended Progressive Tax?

    Throughout history to present days, policymakers, social commentators and others have oftentimes viewed conscription as a natural extension of secondary education, and an important institution for vocational training. This paper uses Swedish administrative data and exploits a reform in 2004, implying a sudden downsizing of the military, to identify the causal effects of peacetime conscription on later labour market outcomes and education. I find that unemployment increased in the short run, and lasted up to four years after service. There are no significant overall effects on income or educational attainment. However, these average effects hide a large heterogeneity. High ability conscripts fall behind their counterparts who did not start military service, both in terms of income and employment. Furthermore, the results suggest that the effect is attributed to high ability conscripts assigned as privates. In contrast, no such evidence is found for conscripts assigned to officer training, despite the fact that all of them have a high ability, and a longer time in service. Plausibly, high ability conscripts have high opportunity costs of doing military service, and the civilian benefits from training as privates are too small to counteract these costs. The results highlight the importance of precise matching of aptitude to type of training or education, an insight that might be generalized to other contexts beyond conscription.

    Citizenship, Social Capital and the Role of Conscription: Evidence from Sweden

    Many scholars have argued that conscription has played an important role as a nation-builder throughout history. Today, advocates of conscription often put forward its potential to induce citizenship and civic engagement. This paper addresses this claim by studying the causal effects of military service on civic engagement by using Swedish administrative data on election participation, blood donation, and the payment of a mandatory, but highly evaded, fee to the public broadcasting service. I study two qualitatively very different conscription systems from two different eras in Sweden, yielding a high external validity. To study the effects of universal conscription (almost all healthy and fit men serve) during the early 1990s, I use an empirical strategy similar in spirit to work using randomly assigned judges as an instrument. To identify the effects of selective conscription (a small fraction of motivated and positively selected men serve), I exploit a reform in 2004, implying a sudden downsizing of the military. In contrast to the previous correlational literature, the results show small and insignificant point estimates for all outcomes in both populations studied. Hence, I find no evidence of any causal effects of military service on civic engagement in either a selective-, or in a universal conscription system

    The Effect of Military Conscription on the Formation of Criminal Behaviour: Evidence from a Natural Experiment

    Conscription has been suggested to be a policy-tool to break young men's anti-social life-trajectories. This paper uses Swedish administrative data and exploits a reform in 2004, implying a sudden downsizing of the military, to identify the causal effects of peacetime conscription on contemporaneous, short- and medium-term crime. I find no evidence of any effects on criminal activity while in service. However, the post-service results show crime increasing effects of military service at the intensive margin (number of convictions), but not at the extensive margin (probability of conviction). The overall crime increasing effect seems to be primarily driven by thefts. This study finds no support for increased overall violent behaviour or that the military context per se induces anti-social behaviour. Rather, some suggestive evidence for worsened labour market opportunities for some groups is documented as a plausible mechanism behind the crime increasing results.

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    Societal Impacts of Modern Conscription: Human Capital, Social Capital and Criminal Behaviour
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  • Disputation: 2020-06-12 15:00 Hörsal 7, hus D, Stockholm
    Kalniņš, Aigars
    Stockholms universitet, Humanistiska fakulteten, Institutionen för slaviska och baltiska språk, finska, nederländska och tyska.
    Studies in Latvian Comparative Dialectology: —with special focus on word-final *–āj(s)/*–ēj(s) and *–āji(s)/*–ēji(s)2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The thesis consists of four interconnected studies of various topics in the fields of Latvian dialectology and historical linguistics: (1) apocope and shortening; (2) loss of the present 2nd singular endings *i and *ɨ; (3) the development of the participle desinences *–ājis *ējis; (4) the ā and ēstem locative singular endings. A recurrent theme is a potential loss of *j in the phonological sequences *āji(s) *ēji(s), which were subsequently contracted to *āj(s) *ēj(s). In this regard, the first study provides the necessary East Baltic context, while studies 2, 3 and 4 investigate the relevant evidence in the Latvian dialects. At the same time, however, each of the topics is also studied on its own terms.

    In the first study, an improved account of apocope and shortening is formulated. It is argued that the primary apocope affected all unaccented short vowels, including *u, but that it took place before the accent retraction. Endings that were only affected in immobile paradigms were restored on the model of their counterparts in mobile paradigms. The secondary apocope in second posttonic syllables, which traditionally accounts for the occasional loss of inherited long vowels and diphthongs, is dated after accent retraction but restricted to *i. This implies that a series of endings such as d.sg. am, d.pl. Vms, ill.sg. Vn, 1.pl. Vm a.o. contained short vowels when the primary apocope set in. Unless Leskien’s Law operated in Latvian, the evidence suggests that the final vowels in these endings were short. If Lithuanian excludes Leskien’s Law in a given case, then the Latvian evidence is compelling, e.g., PEB d.sg.m. *amu or *ami rather than *amọ̄(i̯).

    The second study investigates present 2nd singular forms with and without a distinct ending in the Latvian dialects. The most archaic distribution seems to be the one found in Blīdene106, where only the derived presents are endingless in the indicative. Studies 2, 3 and 4 also give a comprehensive overview of the development of word-final *āj(s) *ēj(s) and *āji(s) *ēji(s). Both *āj *ēj and *āji *ēji yielded ā ē in Low Latvian, while High Latvian might have a contrast between accented āi̯ ēi̯ and unaccented ā ē. High Latvian reflects *ājs *ējs and *ājis *ējis as ājs ējs, but the Low Latvian developments are unclear. Accented *ājs *ējs yield āš ēš but in unaccented position there may be up to three phonologically regular reflexes: āš ēš, aiš eiš and ais eis. In Vidzeme and Zemgale, *ājis *ējis must have merged with *ājs *ējs, but in Courland *ājis *ējis were possibly apocopated only after *ājs *ējs had become āš ēš.

    Accordingly, only Low Latvian â ê can be reflexes of the old inessive. Low Latvian ai ei cannot be cognate with â ê but might continue the old adessive. If Low Latvian ã2 2 reflect the illative, then the three pairs, along with dialectal adverbs in uop, represent all four East Baltic local cases, which therefore must have existed at least as syntactic constructions in ProtoEast Baltic. The enigmatic High Latvian āstem locative singular ending â is identified with Low Latvian ai rather than â, which explains its remarkable lack of labialisation but implies a development *ˌaî > ˌâ.

    The utility of the proposed phonetic loss of *j is limited to disyllabic forms like l.sg. *tâji ‘that’ prs.2.sg. *smeji ‘laugh’ ptc. *gãjis ‘go,’ all of which might also be analogical, and it seems best to reject it.

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    Studies in Latvian Comparative Dialectology: —with special focus on word-final *–āj(s)/*–ēj(s) and *–āji(s)/*–ēji(s)
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  • Disputation: 2020-06-15 10:00 sal FB42, AlbaNova universitetscentrum, Stockholm
    K Manikandan, Sreekanth
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Non-equilibrium thermodynamics at the microscopic scales2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    An inherent feature of small systems in contact with thermal reservoirs, be it a pollen grain in water, or an active microbe flagellum, is fluctuations. Even with advanced microscopic techniques, distinguishing active, non-equilibrium processes defined by a constant dissipation of energy to the environment from passive, equilibrium processes is a very challenging task and a vastly developing field of research. For small (microscopic) systems in contact with thermal reservoirs, the experimental / theoretic framework that addresses these fundamental questions, is called stochastic thermodynamics.

    In this thesis, we study the stochastic thermodynamics of microscopic machines with colloidal particles as working substances. In particular, we use a path integral based framework to characterize the fluctuations of thermodynamic observables, such as Work, Heat and Entropy production in colloidal heat engines. We obtain exact analytic solutions at finite operational times and the results reveal model independent features of Work and Efficiency fluctuations.

    We also discuss the thermodynamic uncertainty relations, which relate current fluctuations in non-equilibrium steady states to the average rate of entropy production. Based on this relation, as well as exact analytical solutions for explicit models, we propose a simple and effective way to infer dissipation from current fluctuations in non-equilibrium systems, from short empirical trajectories.

    Finally, we conclude with a discussion on possible extensions of our results.

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    Non-equilibrium thermodynamics at the microscopic scales
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  • Disputation: 2020-06-15 10:00 sal G, Arrheniuslaboratorierna, Stockholm
    Lorentzon, Louise
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Nationalekonomiska institutionen.
    Empirical Essays on Public Policies: Social Insurances, Safety Nets, and Health Care2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Screening Efficiency in Sickness Insurance: Evidence from a Spell Limit Reform

    I estimate the effects of the removal of a limit on sick leave spells in the Swedish Sickness Insurance program, on labor market outcomes and sick leave. The removal of the spell limit led to longer sick leave spells. I also find that the removal led to a reduction in the share of people who are neither working, nor receiving sickness benefits. A conceptual framework is used to interpret the results in terms of benefits screening efficiency, which is found to increase through the removal of the spell limit. The identification is based on a regression discontinuity design, using the timing of sick leave start dates and the abolition of the spell limit.

    Long-Term Effects of Cash Transfers: Evidence from a Swedish Reform

    Do short-term cash transfers to the poor deliver long-term benefits? This paper studies a unique program introduced in Sweden in the 1930s. The program made large transfers – on average approximately 30 percent of total income in the collected sample – to widows with children. Income and family-size thresholds, combined with child age cutoffs, generate plausibly exogenous variation in program exposure. By digitizing and linking historical records to later administrative datasets, I study the long-term effects of this program. Focusing on life expectancy, I find no significant long-term effects; however, the estimates are imprecisely measured due to the limited sample size.

    Inertia of Dominated Pension Investments: Evidence from an Information Intervention

    In this paper we empirically investigate potential causes of imperfect competition in the fund market, as characterized by high price dispersion among comparable funds. We discriminate between three main hypotheses on the demand side: a lack of awareness of price dispersion, search costs, and financial illiteracy. A large-scale field experiment is conducted in the Swedish Premium Pension system. Information letters are sent to pension savers in two index funds, where there exists a cheaper fund with the same index strategy. We show that an information intervention that increases awareness of a cheaper, dominating fund, and reduces search costs to find such an alternative, can significantly improve households’ real investment allocations. Nonetheless, a vast majority of savers who are sent information about the name of the dominating fund do not switch funds. Thus, the high degree of inertia in pension investments remains even when search friction for identifying dominating alternatives are eliminated.

    Midwives and Maternal Mortality: Evidence from a Midwifery Policy Experiment in 19th Century Sweden

    This paper estimates the effect of a historical midwifery policy experiment on maternal mortality, infant mortality, and stillbirth during the period from 1830 to 1894 in Sweden. Exploiting sharp changes or “discontinuities” across time and place in the availability of trained and licensed midwives as an exogenous source of variation, we find that a doubling of trained midwives leads to a 20-40 percent reduction in maternal mortality and to a 20 percent increase in the uptake of midwife-assisted homebirths. The results thus suggest that a 1 percent increase in the share of midwife-assisted homebirths decreases maternal mortality by as much as 2 percent, which is a remarkable finding given that midwife training was only 6-12 months at that time. The results of this study contribute to the current debate about the most effective strategy to reduce the unacceptably high rate of maternal mortality in many developing countries, especially in low-resource settings.

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    Empirical Essays on Public Policies
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  • Disputation: 2020-06-15 10:00 The link will be made available at su.se/romklass/evenemang, Stockholm
    Berton, Marco
    Stockholms universitet, Humanistiska fakulteten, Romanska och klassiska institutionen.
    Riqueza léxica y expresión escrita en aprendices suecos de ELE: Proficiencia general, competencia léxica pasiva, tipo y complejidad de la tarea2020Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The present study explored lexical richness in the written production of Swedish university students of Spanish as a foreign language. Two aspects of lexical richness were investigated in the study, i.e., diversity (the ability to use a varied lexical repertoire), and sophistication (the proportion of relatively infrequent words). The written data were elicited by means of two task types, namely a narrative task and a decision-making task. The main aim of the study was investigating the effect of the factors overall proficiency, passive vocabulary knowledge, manipulation of task complexity and task type on lexical richness. Moreover, the study inquired into the predicting power of the first three factors in relation to lexical richness within each task type. Overall proficiency was measured by means of a cloze test, while an estimation of passive vocabulary knowledge was obtained through a word recognition test. The effect of the manipulation of task complexity was examined by using two different versions of each task. The less complex version of the narrative task was based on a cartoon strip with a tight structure and no background events. On the contrary, in the more complex version the cartoon strip depicted a story without a clear sequence and with background events which are relevant to the story plot. Regarding the decision-making task, task complexity was manipulated by changing the number of elements involved. The task itself consisted in writing a message to a friend suggesting a holiday destination. To do so, the participants had to consider the friend´s needs and check them against the possibilities offered by a travel agency. The less complex version included two destinations, while the more complex one contained six. When analysing the effect of manipulating task complexity, structural complexity measures were included with the purpose of investigating if changes in lexical richness go hand in hand with or at the expense of changes in structural complexity. The results of the analysis of these three factors showed different patterns depending on the task type examined. These results suggest that overall proficiency seems to have an effect on lexical richness only in the narrative task, whereas passive vocabulary knowledge would influence lexical richness only in the decision-making task. The manipulation of task complexity apparently affected lexical diversity and structural complexity in the narrative task, on the one hand, and lexical sophistication in the decision-making task, on the other hand. When manipulating task complexity, the relationship between lexical richness and structural complexity turned out to be unclear, as it varied in unpredictable ways depending on the learners´ overall proficiency and passive vocabulary knowledge. The intrinsic complexity inherent to task type, i.e. the different cognitive load that different task types place on the learner, showed the most consistent effect in the study, as it was supported by all the measures of lexical richness and some measures of structural complexity. Finally, the regression model conformed by overall proficiency, passive vocabulary knowledge, and the manipulation of task complexity did not prove to be suitable to predict lexical richness in either of the task types under investigation in the study.

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    Riqueza léxica y expresión escrita en aprendices suecos de ELE
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