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  • Disputas: 2017-10-20 10:00 David Magnussonsalen (U31), Stockholm
    von Below, Camilla
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Psykologiska institutionen.
    When psychotherapy does not help: ...and when it does: Lessons from young adults' experiences of psychoanalytic psychotherapy2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The process and outcome of psychoanalytic psychotherapy have been studied for a long time. However, the experiences of patients, particularly in therapies where goals were not met, have not yet been the target of extensive research. Psychoanalytic psychotherapy with young adults might face particular challenges. The overall aim of this thesis was to explore the experiences of young adults in psychoanalytic psychotherapy, with a particular focus on differences between suboptimal therapies and therapies with generally good outcome. The setting was naturalistic, and perspectives of the patient, therapist and observer were combined. Qualitative and quantitative methods were used. Study I explored experiences of psychotherapy process and outcome among seven patients in psychoanalytic psychotherapy, who expressed dissatisfaction. Interviews at termination and 18 months later were analysed using grounded theory and compared to therapist experiences. Patients experienced abandonment with their problems in and after therapy, since therapy according to the patients lacked connections to daily life, as well as flexibility, activity and understanding from the therapist. Therapists presented a different picture of the same therapies, mainly focused on the difficulties of the patients. Study II analysed the experiences of 20 non-improved or deteriorated young adult psychotherapy patients at termination of therapy and 36 months later. Non-improvement and deterioration were calculated based on the reliable change index on self-rating scores. The grounded theory analysis of interviews established spinning one’s wheels as a core category. The relationship to the therapist was described as artificial, although at times helpful. Participants experienced their own activity in life and active components of therapy as helpful, but thought focus in therapy was too much on past experiences. Study III explored the experiences of 17 young adult patients, in psychoanalytic individual or group therapy, overcoming depression. The analysis of interviews from therapy termination and 18 months later indicated that finding an identity and a place in life were perceived as intertwined with symptom relief. Negative experiences included difficulties to change oneself, fear of change, and problems in therapy, such as too little activity on the therapist’s part.

    The results were discussed in relation to young adulthood, therapeutic alliance, mentalization, and attachment. The conclusion was expressed in a comprehensive process model of suboptimal therapy with young adults, with suggested ways to prevent such a development. The therapist’s meta-communication and correct assessment of the patient’s mentalization capacity from moment to moment are proposed as crucial. Regarding clinical implications, therapists of young adult patients need to establish meta-communication on therapy progress, as even experienced therapists might be unaware of dissatisfaction or deterioration. Meta-communication could be considered part of the treatment itself, as it may foster mentalization and good outcome. Further, the period of young adulthood entails decisions and developing an adult life, and therapists need to make room for this by active interventions.

  • Disputas: 2017-10-20 13:00 Lilla Hörsalen, Naturhistoriska riksmuseet, Stockholm
    Langström, Christer
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för pedagogik och didaktik.
    Lärande i professionellt samtalsstöd: Villkor för vuxna arbetssökandes karriärprocesser2017Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    The aim of this thesis is to contribute knowledge to how professional conversations such as career guidance and coaching contribute to adults’ learning in their career development. Unemployment is a topic that has recently gained much attention in the political debate as well as in society. Career guidance and coaching have largely been used as a means for supporting the unemployed in their career development. This thesis takes the adult job seekers’ perspective for increasing our knowledge of the learning-process taking place in professional conversations. The study draws on theories of learning, recognition, career development, dialogue and relationships. The thesis focuses on the following research questions:How do participants experience professional conversations?

    What learning conditions emerge from the participants’ experiences?

    How does learning take place and what meaning does this have for the participants in their career development?

    The study was conducted in two municipal labor market projects. The empirical data is based on 22 qualitative interviews with 16 long-term unemployed, 16 initial interviews and six follow-up interviews one-and-a-half year after the first interview. The interviews were conducted as reflective conversations, about participants past experiences of professional conversations in order to benefit participants’ own stories.

    The results show that:

    Learning in professional conversations is influenced by the tensions between participants’ self-image, societal demands on the outcome of conversations and how the conversations are organized.

    The participants’ previous experiences of different forms of employment measures seem to affect their experiences of the professional conversations.

    Participants’ previous experiences of professional conversations affect the participants’ learning in different ways.

    How the professionals have treated the participants affects the participants’ confidence or skepticism towards the professional helper. It opens or closes for the relationship and work alliance between them.

    The participants’ emotional experiences in their encounter with professionals appear to be an important driving force in the learning process. Small nuances such as how the professional attitude is perceived are crucial to the learning process. The dissertation shows that emotional and relational aspects, largely, influence participants’ learning process in professional conversation. Three conditions for learning were identified: Pre-existing conditions, organizational conditions, and conversation related conditions. Four learning processes have also been identified: The positive, the turning, the adaptive and the negative. These learning processes seem to affect the continuing career process in different ways.

  • Disputas: 2017-10-20 13:00 Magnélisalen, Stochkolm
    Ogris, Christoph
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Global functional association network inference and crosstalk analysis for pathway annotation2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Cell functions are steered by complex interactions of gene products, like forming a temporary or stable complex, altering gene expression or catalyzing a reaction. Mapping these interactions is the key in understanding biological processes and therefore is the focus of numerous experiments and studies. Small-scale experiments deliver high quality data but lack coverage whereas high-throughput techniques cover thousands of interactions but can be error-prone. Unfortunately all of these approaches can only focus on one type of interaction at the time. This makes experimental mapping of the genome-wide network a cost and time intensive procedure. However, to overcome these problems, different computational approaches have been suggested that integrate multiple data sets and/or different evidence types. This widens the stringent definition of an interaction and introduces a more general term - functional association. 

    FunCoup is a database for genome-wide functional association networks of Homo sapiens and 16 model organisms. FunCoup distinguishes between five different functional associations: co-membership in a protein complex, physical interaction, participation in the same signaling cascade, participation in the same metabolic process and for prokaryotic species, co-occurrence in the same operon. For each class, FunCoup applies naive Bayesian integration of ten different evidence types of data, to predict novel interactions. It further uses orthologs to transfer interaction evidence between species. This considerably increases coverage, and allows inference of comprehensive networks even for not well studied organisms. 

    BinoX is a novel method for pathway analysis and determining the relation between gene sets, using functional association networks. Traditionally, pathway annotation has been done using gene overlap only, but these methods only get a small part of the whole picture. Placing the gene sets in context of a network provides additional evidence for pathway analysis, revealing a global picture based on the whole genome.

    PathwAX is a web server based on the BinoX algorithm. A user can input a gene set and get online network crosstalk based pathway annotation. PathwAX uses the FunCoup networks and 280 pre-defined pathways. Most runs take just a few seconds and the results are summarized in an interactive chart the user can manipulate to gain further insights of the gene set's pathway associations.

  • Disputas: 2017-10-26 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Schiller, Nina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Insertion studies of model transmembrane segments into bacterial and eukaryotic membranes2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Cells are encapsulated by a biological membrane in order to separate the cell interior from the surrounding environment. Different lipids and proteins compose the membrane and present a semi-permeable barrier for the diffusion of ions and molecules across the lipid bilayer. Membrane proteins also mediate the passage of signals between the interior and the exterior of the cell.   To ensure the proper functioning of membrane proteins, it is essential that nascent membrane proteins are correctly integrated into the lipid bilayer to be able to fold and oligomerize.  In this thesis, an engineered protein containing two natural transmembrane segments followed by an additional test segment, has been used as a model protein to study (i) sequence requirements for translocon-mediated insertion of the test segment, (ii) dynamics of nascent membrane proteins undergoing translocon-mediated insertion and (iii) to carry out an extensive mutagenesis scan to identify critical residues in the mammalian arrest peptide Xbp1 that enhances translational stalling in the ribosome. This provides a toolbox of arrest peptides with different stalling strengths that will be useful for force measurements on nascent protein chains.     

  • Disputas: 2017-10-27 10:00 Magnélisalen, Kemiska övningslaboratoriet
    Ståhle, Jonas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Structure Elucidations of Bacterial Polysaccharides using NMR Spectroscopy and Bioinformatics2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Carbohydrates are ubiquitous components in nature involved in a range of tasks. They cover every cell and contribute both structural stability as well as identity. Lipopolysaccharides are the outermost exposed part of the bacterial cell wall and the primary target for host-pathogen recognition. Understanding the structure and biosynthesis of these polysaccharides is crucial to combat disease and develop new medicine. Structural determinations can be carried out using NMR spectroscopy, a powerful tool giving information on an atomistic scale. This thesis is focused on method development to study polysaccharide structures as well as application on bacterial lipopolysaccharides. The focus has been to incorporate a bioinformatics approach prior to analysis by NMR spectroscopy, and then computer assisted methods to aid in the subsequent analysis of the spectra.

    The third chapter deals with the recent developments of ECODAB, a tool that can help predict structural fragments in Escherichia coli O-antigens. It was migrated to a relational database and the aforementioned predictions can now be made automatically by ECODAB. The fourth chapter gives insight into the program CASPER, a computer program that helps with structure determination of oligo- and polysaccharides. An approach to determine substituent positions in polysaccharides was investigated. The underlying database was also expanded and the improved capabilities were demonstrated by determining O-antigenic structures that could not previously be solved. The fifth chapter is an application to O‑antigen structures of E. coli strains. This is done by a combination of NMR spectroscopy and bioinformatics to predict components as well as linkages prior to spectra analysis. In the first case, a full structure elucidation was performed on E. coli serogroup O63, and in the second case a demonstration of the bioinformatics approach is done to E. coli serogroup O93. In the sixth chapter, a new version of the CarbBuilder software is presented. This includes a more robust building algorithm that helps build sterically crowded polysaccharide structures, as well as a general expansion of possible components. 

  • Disputas: 2017-10-27 10:00 hörsal 11, hus F, Stockholm
    Östergren, Olof
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Sociologiska institutionen.
    Understanding the Educational Gradient in Mortality2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    There is a positive association between education and longevity. Individuals with a university degree tend to live longer than high school graduates who, in turn, live longer than those with compulsory education. These differences are neither larger nor smaller in Sweden than in other European countries, despite its ambitious welfare-state policies. Furthermore, educational differences in longevity are growing, especially among women.

    In this thesis I look at the structural, individual and behavioral processes which generate and maintain the educational gradient in mortality. This is done by compiling theoretical insights and empirical research from a range of scientific disciplines. In doing so, this thesis aims to contribute to a more comprehensive understanding of the educational gradient in mortality.

    Several factors contribute to the association between education and health. Social and biological processes initiated in early life influence both educational achievement and adult health. Education helps individuals become more effective as agents by fostering generic skills such as information-gathering and decision-making. This aspect of education, learned effectiveness, promotes control and health regardless of available resources and prevailing conditions. Education thus has a direct influence on health. Education also indirectly influences health by giving access to better occupational positions and higher incomes, as well as by promoting social capital and healthy habits.

    The empirical section of the thesis consists of four separate quantitative studies using register data. Three of the studies use Swedish national register data while one uses register data from 18 European populations. The results indicate that widening income inequalities in mortality have contributed to a widening of educational inequalities in mortality, since education is a determinant of income. Both alcohol and smoking contribute to educational inequalities in longevity, but smoking has played an especially pronounced role in the widening of inequalities among women. Smoking represents a significant part of the explanation as to why women with low education have experienced smaller gains in life expectancy than the rest of the population. The results also indicate that the general trend towards more well-educated populations has contributed to the widening educational inequalities in mortality in Europe and that education is a stronger predictor of mortality among low income-earners than among the rest of the population.

  • Disputas: 2017-10-27 13:00 Nordenskiöldsalen, Geovetenskapens hus, Stockholm
    Kuns, Brian
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Kulturgeografiska institutionen.
    Peasants and Stock Markets: Pathways from Collective Farming in the Post-Soviet Grain-Belt2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    What happened in the post-Soviet, European grain-belt after collective farms were dissolved and in what way can we say that collective farm legacies influence agrarian developments in this region today? These are the main questions of this thesis, which is a work of critical human geography, but is also inspired by theories, methods and approaches from the social sciences, broadly defined. Territorially, the focus is Ukraine, but several articles in this thesis take a wider geographic perspective beyond Ukraine, in particular taking into account the role of Nordic investors in the agrarian sector in Ukraine and Russia. The main aim of this thesis is to examine how farms of different sizes – from small peasant farms to super large corporate farms – develop and change in post-communist circumstances. Another purpose is to reinterpret Soviet agrarian history, in light of what happened after the collapse of communism, in order to incorporate the Soviet experience in a global historical narrative, and to better understand the legacy of collective farming today.

    These issues are explored in four papers and a comprehensive summary. The first article examines small-scale, household “peasant” agriculture in southern Ukraine and shows the conditions and factors, which have contributed to an impressive intensification of farming in certain villages. The second article investigates large-scale, Nordic investments in Ukrainian and Russian agriculture, with the aim of explaining why many (but not all) such investments have not succeeded to the degree that investors hoped. The third paper focuses on the legacy and afterlife of Soviet-era investments in large-scale irrigation in southern Ukraine, and uses the post-Soviet reincarnation of irrigation in this region to problematize traditional narratives on Soviet environmental management in a global context. The fourth paper, with a wider historical lens, explains the link between collective farms and today’s agroholding agriculture in much of the region, while also discussing the sustainability crisis in agriculture both in a Soviet and post-Soviet context, concluding with a description of a possible and ironic (but by no means inevitable) scenario whereby post-Soviet agriculture saves global capitalism. 

    Theoretically, this thesis is informed by agrarian political economy; related, contemporary debates on the financialization of agriculture; and critical human geography discussions on uneven development and the geographies of difference. This thesis also is inspired by Actor Network Theory, and the view that reality is constituted by hybrid subject-objects, which are instantiated through the agency of an assemblage or network of different actors, material things, discourses, institutions, etc... While such Actor Network approaches are certainly not new, their application to Soviet and post-Soviet change is relatively new. The source material, which is the basis for the empirical approach of this thesis, is eclectic, and produced via mixed methods from different locations. Analysis is based on interviews (75 interviews in southern Ukraine, in Kyiv, and in Stockholm, plus 28 visits to household farms in one study village in southern Ukraine); participant observation (carried out in the study village in southern Ukraine and in corporate shareholder meetings mostly in Stockholm); various texts, such as corporate documents and newspaper commentary; agricultural statistics; and satellite data. 

    Among other conclusions, this thesis argues that, given certain factors, small-scale, household agriculture can be viable, at the same time that the concentration and consolidation of agriculture into large-scale holdings is likely to continue, at least in the short term. This thesis also highlights similarities between Soviet and capitalist agriculture in a global historical context, which is one reason that the transformation from Soviet to capitalist agriculture could occur so fast in some areas.

  • Disputas: 2017-10-27 13:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Kranak, Verina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Investigating Hydrogenous Behavior of Zintl Phases: Interstitial Hydrides, Polyanionic Hydrides, Complex Hydrides, Oxidative Decomposition2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis is an investigation into the hydrogenous behavior of Zintl phases. Zintl phases are comprised of an active metal (i.e alkali, alkaline earth, and rare earth) and a p-block element. The discussion gives an overview of the influence hydrogen affects the electronic and geometric structure of Zintl phases and subsequent properties. Incorporation of hydrogen into a Zintl phase is categorized as either polyanionic or interstitial Zintl phase hydrides. In the former the hydrogen covalently bonds to the polyanion and in the latter the hydrogen behaves hydridic, coordinates exclusively with the active metal, leading to an oxidation of the polyanion. Synthesis of hydrogenous Zintl phases may be through either a direct hydrogenation of a Zintl phase precursor or by combining active metal hydrides and p-block elements. The latter strategy typically leads to thermodynamically stable hydrides, whereas the former supports the formation of kinetically controlled products. 

    Polyanionic hydrides are exemplified by SrAlGeH and BaAlGeH. The underlying Zintl phases SrAlGe and BaAlGe have a structure that relates to the AlB2 structure type. These Zintl phases possess 9 valence electrons for bonding and, thus, are charge imbalanced species. Connected to the charge imbalance are superconductive properties (the Tc of SrAlGe and BaAlGe is 6.7 and 6.3 °C, respectively). In the polyanionic hydrides the hydrogen is covalently bonded as a terminating ligand to the Al atoms. The Al and Ge atoms in the anionic substructure [AlGeH]2- form corrugated hexagon layers. Thus, with respect to the underlying Zintl phases there is only a minimal change to the arrangement of metal atoms. However, the electronic properties are drastically changed since the Zintl phase hydrides are semiconductors. 

    Interstitial hydrides are exemplified by Ba3Si4Hx (1 < x < 2) which was obtained from the hydrogenation of the Zintl phase Ba3Si4. Ba3Si4 contains a Si46- “butterfly” polyanion. Hydrogenation resulted in a disordered hydride in which blocks of two competing tetragonal structures are intergrown. In the first structure the hydrogen is located inside Ba6 octahedra (I-Ba3Si4H), and in the second structure the hydrogen is located inside Ba5 square pyramids (P-Ba3Si4H2). In both scenarios the “butterfly anions appear oxidized and form Si44- tetrahedra.

    Hydrogenation may also be used as a synthesis technique to produce p-block element rich Zintl phases, such as silicide clathrates. During hydrogenation active metal is removed from the Zintl phase precursor as metal hydride. This process, called oxidative decomposition, was demonstrated with RbSi, KSi and NaSi. Hydrogenation yielded clathrate I at 300 °C and 500 °C for RbSi and KSi, respectively. Whereas a mixture of both clathrate I and II resulted at 500 °C for NaSi. 

    Low temperature hydrogenations of KSi and RbSi resulted in the formation of the silanides KSiH3 and RbSiH3. These silanides do not represent Zintl phase hydrides but are complex hydrides with discrete SiH3- complex species. KSiH3 and RbSiH3 occur dimorphic, with a disordered α-phase (room temperature; SG Fm-3m) and an ordered β-phase (below -70 °C; SG = Pnma (KSiH3); SG = P21/m ( RbSiH3)). During this thesis the vibrational properties of the silyl anion was characterized. The Si–H stretching force constants for the disordered α-phases are around 2.035 Ncm-1 whereas in the ordered b-forms this value is reduced to ~1.956 Ncm-1. The fact that SiH3- possesses stronger Si-H bonds in the α-phases was attributed to dynamic disorder where SiH3- moieties quasi freely rotate in a very weakly coordinating alkali metal ion environment.

  • Disputas: 2017-10-27 13:00 sal 14, hus 5, Kräftriket, Stockholm
    Wierstra, Felix
    Stockholms universitet, Naturvetenskapliga fakulteten, Matematiska institutionen.
    Hopf Invariants in Real and Rational Homotopy Theory2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In this thesis we use the theory of algebraic operads to define a complete invariant of real and rational homotopy classes of maps of topological spaces and manifolds. More precisely let f,g : M -> N be two smooth maps between manifolds M and N. To construct the invariant, we define a homotopy Lie structure on the space of linear maps between the homology of M and the homotopy groups of N, and a map mc from the set of based maps from M to N, to the set of Maurer-Cartan elements in the convolution algebra between the homology and homotopy. Then we show that the maps f and g are real (rational) homotopic if and only if mc(f) is gauge equivalent to mc(g), in this homotopy Lie convolution algebra. In the last part we show that in the real case, the map mc can be computed by integrating certain differential forms over certain subspaces of M. We also give a method to determine in certain cases, if the Maurer-Cartan elements mc(f) and mc(g) are gauge equivalent or not.

  • Disputas: 2017-11-02 09:30 sal FA32, AlbaNova universitetscentrum, Stockholm
    Bessidskaia Bylund, Olga
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Top quark and heavy vector boson associated production at the ATLAS experiment: Modelling, measurements and effective field theory2017Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    The Standard Model (SM) of particle physics describes the elementary particles that constitute matter and their interactions. The predictions of the SM have been confirmed by numerous experimental results. However, several questions of particle phenomena in the Universe remain unaddressed by the Standard Model, which suggests that the SM can be extended to a more complete theory. One approach to search for extensions of the SM is to test the predictions of the Standard Model in high precision measurements and see whether the results falsify the SM. For this reason, production of the ttZ and ttW processes at the ATLAS experiment at CERN is studied. It is investigated whether the SM gives correct predictions for these processes and how much room there is for contributions from new physics that give similar final states.

    Three measurements of ttZ and ttW production are performed. The first measurement is performed at 8 TeV collision energy. The next measurement uses data collected in 2015 at 13 TeV collision energy, when the production cross sections for these processes are considerably larger. The third measurement uses ten times as much data at 13 TeV collision energy. This analysis is not public at the time of writing, so only preliminary results for the expected sensitivity are presented.

    The new physics affecting ttZ production is parametrised in the model-independent framework of Effective Field Theory. Five effective operators that can affect ttZ production are studied and their coefficients are constrained in a fit to simulated data for the third measurement.

    The major background process tWZ is modelled at NLO in QCD. In order to avoid overlaps with ttZ, the Diagram Removal (DR) method is employed in two versions: one where the quantum interference is neglected (DR1) and another where it is modelled (DR2). The differences between the two predictions are explored and enter the measurement as a modelling uncertainty.

  • Disputas: 2017-11-02 10:00 De Geersalen, Geovetenskapens hus, Stockholm
    Kuusela, Tommy
    Stockholms universitet, Humanistiska fakulteten, Institutionen för etnologi, religionshistoria och genusvetenskap.
    "Hallen var lyst i helig frid": Krig och fred mellan gudar och jättar i en fornnordisk hallmiljö2017Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    This thesis is the first study to examine the interaction between gods and giants in Old Norse mythology from the perspective of Iron Age halls. Its central aim is to contextualise Old Norse mythological narratives that describe the interactions between gods and giants in a hall environment, and to show how the mythological depictions can be compared to the norms and rules found in Iron Age hall culture, especially in connection with its warrior ideology. The relationships observed also apply to the Iron Age’s aristocratic sovereigns and their dynamic dealings – both peaceful and martial – found in the connection and rivalry between different halls and hall owners. The giants are related to the concept of “the Other”, and as hall-owners can thus be contextualised with real social relations in Iron Age society. The investigation centers arounds key topics from the perspective of a hall setting, departing from mythic traditions regarding Óðinn and Þórr as guests in the halls of giants. These topics include grið within the hall; the good and generous host; the dangerous and hostile guest; the hall as an arena for knowledge and mead; and finally the destruction of halls as an attack on the hall owner’s fame and honour. Similarities and differences between myths about Óðinn’s and Þórr’s interaction with hall-owning giants are examined in depth, and it is argued that Óðinn embodies wisdom and extracts knowledge or valuables from the giants by cunning tricks or manipulation, having (usually) travelled there alone and in disguise. Þórr, on the other hand, is argued to embody physical strength, honour, glory and courage, and his dealings with the giants revolve around these issues. He seldom seems to travel alone or under cover, and when his courage or honour is threatened, his response is to kill his host (and his retinue) and to destroy the giant’s hall. It is argued that the Old Norse conception of the world is to be understood as neither dualistic or monistic. Instead, it is proposed that the myths can be understood from a perspective of conflicts that are temporal and not permanent in nature.

  • Disputas: 2017-11-03 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Liebau, Jobst
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Taming the Griffin: Membrane interactions of peripheral and monotopic glycosyltransferases and dynamics of bacterial and plant lipids in bicelles2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Biological membranes form a protective barrier around cells and cellular compartments. A broad range of biochemical processes occur in or at membranes demonstrating that they are not only of structural but also of functional importance. One important class of membrane proteins are membrane-associated glycosyltransferases. WaaG is a representative of this class of proteins; its function is to catalyze one step in the synthesis of lipopolysaccharides, which are outer membrane lipids found in Gram-negative bacteria.

    To study protein-membrane complexes by biophysical methods, one must employ membrane mimetics, i.e. simplifications of natural membranes. One type of membrane mimetic often employed in solution-state NMR is small isotropic bicelles, obloid aggregates formed from a lipid bilayer that is dissolved in aqueous solvent by detergent molecules that make up the rim of the bicelle.

    In this thesis, fast dynamics of lipid atoms in bicelles containing lipid mixtures that faithfully mimic plant and bacterial membranes were investigated by NMR relaxation. Lipids were observed to undergo a broad range of motions; while the glycerol backbone was found to be rigid, dynamics in the acyl chains were much more rapid and unrestricted. Furthermore, by employing paramagnetic relaxation enhancements an ‘atomic ruler’ was developed that allows for measurement of the immersion depths of lipid carbon atoms.

    WaaG is a membrane-associated protein that adopts a GT-B fold. For proteins of this type, it has been speculated that the N-terminal domain anchors tightly to the membrane via electrostatic interactions, while the anchoring of the C-terminal domain is weaker. Here, this model was tested for WaaG. It was found by a set of circular dichroism, fluorescence, and NMR techniques that an anchoring segment located in the N-terminal domain termed MIR-WaaG binds electrostatically to membranes, and the structure and localization of isolated MIR-WaaG inside micelles was determined. Full-length WaaG was also found to bind membranes electrostatically. It senses the surface charge density of the membrane whilst not discriminating between anionic lipid species. Motion of the C-terminal domain could not be observed under the experimental conditions used here. Lastly, the affinity of WaaG to membranes is lower than expected, indicating that WaaG should not be classified as a monotopic membrane protein but rather as a peripheral one.

  • Disputas: 2017-11-03 13:00 sal FA32, AlbaNova Universitetscentrum, Stockholm
    Ferretti, Raphael
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    The Circumstellar Environment of Type Ia Supernovae2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Type Ia supernovae (SNe Ia) have proven to be extremely useful for measuring cosmological distances and were used for the discovery of the accelerated expansion of the universe. Although thousands of SNe Ia have been observed to date, many questions surrounding the physics of the explosions and the nature of their progenitor systems remain unanswered. An notable property of many SNe Ia is the relation between extinction due to dust and their colour. For example SN 2014J, the nearest SN Ia in recent years, has an extinction relation which would be very unusual to observe in the Milky Way. One possible explanation to the peculiar extinction could be the presence of circumstellar (CS) dust surrounding the explosions. Incidentally, some proposed progenitor models of SNe Ia suggest that the explosions are surrounded by shells of matter, which could account for the unusual extinction.

    CS gas would be ionised, if it is exposed to the intense ultraviolet (UV) radiation of a SN Ia. The research presented in this thesis focuses on the search for CS gas by observing the effects of photoionisation on absorption lines commonly detected in optical spectra. Simple models suggest that the frequently studied sodium doublet (Na I D) should significantly decrease or even disappear if the gas is in the CS environment. Conversely, the absence of variations implies that the absorbing gas clouds must be far from the explosion, in the interstellar medium (ISM). To date, few SNe Ia have been shown to have variable absorption lines, to which we have added another case with SN 2013gh. Yet, we have also shown that most observations searching for variable absorption lines have been taken at too late phases, when most CS gas will have already been ionised. Setting out to obtain the earliest possible coverage of a SN Ia with high-resolution spectra, we have been able to set strong limits on the presence of CS gas surrounding SN 2017cbv.

    Along with evidence from other observational methods, these results have shown that there is little matter in the CS environments of SNe Ia, suggesting that the peculiar extinction likely results from the dust properties of their host galaxy ISM. Although the progenitor question cannot be resolved by these observations, nondetections of CS gas point to models which do not deposit large amounts of matter in their surroundings.

  • Disputas: 2017-11-03 13:00 hörsal 4, hus B, Stockholm
    Lewén, Aurora
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Ekonomisk-historiska institutionen.
    Resfeber: Berättelser från semesterns barndom 1938−19592017Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    The dissertation provides an in-depth analysis of Swedes’ perceptions about vacations during the period of 1938 to 1959. The aim is to contribute to a more thorough understanding of vacation-related consumption, which in Sweden was of growing economic importance from the 1930s and onwards. The study examines perceptions about the relationship between vacation and work; the experience with nature; interactions with family members and other social relations; relaxation and rest, and the act of travelling. The dissertation also analyzes the adoption of the first Holiday with Pay Act in 1938 and examines how people vacationed during the period. Throughout the study class and gender are used as analytical categories. The principal source material is autobiographical recollections, which consist of written replies to questionnaires sent out by the Nordic Museum. Other sources include materials related to the introduction of the Holiday with Pay Act, mainly the Swedish Government Official Report and the parliamentary debate. Representations of vacations in magazine advertisements are also analyzed.

    Equalization between classes was an important reason for the adoption of the Holiday with Pay Act in 1938. Proponents of the legislation in parliament and, to some extent even the opponents, viewed equalization as a positive outcome of the reform. As a result of the legislation, blue-collar workers, both women and men, were able to enjoy vacations to a greater extent than before. However, large groups, mainly farmers, entrepreneurs, and housewives, continued to lack entitlement to paid vacations, a fact that were debated in parliament. Nevertheless, persons without legal entitlement to paid vacations still occasionally took time off and went on vacations.

    It was relatively common to travel during the vacation, even at the beginning of the period. The desire to experience a contrast to everyday life was prominent. People desired contrast not only with work but also with everyday life outside of work, including regular leisure time, something that is particularly evident in the autobiographical recollections. In one form or another, the desire for contrast permeated views on the various factors examined in the dissertation. Travel represented an ideal way to experience contrast. Nature was more interesting if it was located somewhere else, relaxation and rest was best achieved if one went away, and meeting new people was seen as more exciting than spending time with family.

    Overall perceptions concerning vacation were similar among blue-collar and white-collar workers of both sexes, as well as among housewives, farmers, and entrepreneurs. They all wanted to experience a contrast to everyday life. On a more detailed level, though, these desires took somewhat different forms depending on working conditions and economic circumstances. These common perceptions had economic significance, as going away meant more purchases than staying at home. It was not just a matter of spending what was required for the trip to happen. Travel and the desire for contrast had amplifying effects on other vacation-related consumption as well.

    An English summary of the dissertation is provided.

  • Disputas: 2017-11-08 10:00 Auditorium 215, Humanistvillan, Stockholm
    Hübben, Kelly
    Stockholms universitet, Humanistiska fakulteten, Institutionen för kultur och estetik.
    A Genre of Animal Hanky Panky?: Animal representations, anthropomorphism and interspecies relations in The Little Golden Books.2017Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    This dissertation investigates the visual and verbal representations of animals in a selection of commercial picture books for a young readership of preschool children. The picture books selected are part of the Little Golden Book series. The first twelve books in this series were published in the United States in 1942 and are still in print today, while new books are continually being published. Because these popular picture books have had a broad readership from their inception and the books in the series have a uniform aesthetics, a comparative analysis provides insight into mainstream human-animal relationships. 

    Children’s literature is never innocent, and fraught with power imbalances. Animals become political beings, not only in the sense that they convey a didactic message, but in the sense that each animal representation carries a host of ideas and assumptions about human-animal relations with it. Using a theoretical framework that is grounded in Human Animal Studies (HAS), and more specifically literary animal studies, this dissertation analyzes the representation of human-animal interactions and relationships in different contexts. 

    Before the advent of HAS, anthropocentric, humanist interpretations of animal presence in children’s literature used to be prevalent. Commercial picture books in particular could benefit from readings that investigate animal presence without immediately resorting to humanist interpretations. One way of doing that is to start by questioning how interspecies difference and hierarchy is constructed in these books, verbally, visually and in the interaction between words and images. Based on this, we can speculate about the consequences this may have for the reader’s conceptualization of human-animal relationships. In children’s literature speciesism and ageism often intersect, for example when young children are compared with (young) animals or when animals are presented as stand-ins for young children. This dissertation explores the mechanisms behind the representation of species difference in commercial picture books. 

    The aim of this study is to analyze how commercial picture books like the Little Golden Books harbor a potential to shape young readers’ ideas about humanity and animality, species difference and hierarchy and the possibilities of interspecies interactions. The socializing function that is an important component of all children’s books makes that these picture books can shape readers’ attitudes from an early age. When reading children’s books featuring animals, the particular way these animals are represented guides the reader towards an ideology – and in the West, this ideology is predominantly anthropocentric. In Western cultures, children and animals are commonly thought of as natural allies, and as such they are often depicted as opposed to adult culture. 

    This dissertation identifies the ways in which certain conservative tendencies are activated by these commercial picture books, but also emphasizes that they can be a subversive space where anthropocentrism can be challenged. The case studies developed in this dissertation demonstrate how even so-called ’unsophisticated’ picture books contain interesting strains of animal related ideology worthy of in-depth analysis. The visual and verbal dimensions of these picture books show that these stories are embedded in a cultural context that helps give meaning to the animals. A recurring concern is the function of anthropomorphism and the role it plays in how we value the animals in these books. I am particularly interested in how picture books depict various degrees of anthropomorphism, because it has the potential to challenge species boundaries and disrupt the human-animal dichotomy.

  • Disputas: 2017-11-09 10:00 Vivi Täckholmsalen (Q-salen), NPQ-huset, Stockholm
    Gonska, Nathalie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Proton pathways in energy conversion: K-pathway analogs in O2- and NO-reductases2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Oxygen and nitric oxide reductases are enzymes found in aerobic and anaerobic respiration, respectively. Both enzyme groups belong to the superfamily of Heme-Copper Oxidases, which is further divided into several subgroups: oxygen-reducing enzymes into A-, B- and C-type and nitric oxide reductases into qNORs and cNORs. Oxygen reducing enzymes use the energy released from oxygen reduction to take up electrons and protons from different sides of the membrane. Additionally, protons are pumped. These processes produce a membrane potential, which is used by the ATP-synthase to produce ATP, the universal energy currency of the cell. Nitric oxide reductases are not known to conserve the energy from nitric oxide reduction, although the reaction is highly exergonic.

    Here, the detailed mechanism of a B-type oxidase is studied with special interest in an element involved in proton pumping (proton loading site, PLS). The study supports the hypothesis that the PLS is protonated in one and deprotonated in the consecutive step of the oxidative catalytic cycle, and that a proton is pumped during the final oxidation phase. It further strengthens the previous suggestion that the PLS is a cluster instead of a single residue or heme propionate. Additionally, it is proposed that the residue Asp372, which is in vicinity of the heme a3 propionates previously suggested as PLS, is part of this cluster. In another study, we show that the Glu15II at the entry of the proton pathway in the B-type oxidase is the only crucial residue for proton uptake, while Tyr248 is or is close to the internal proton donor responsible for coupling proton pumping to oxygen reduction.

    The thesis also includes studies on the mechanism and electrogenicity of qNOR. We show that there is a difference in the proton-uptake reaction between qNOR and the non-electrogenic homolog cNOR, hinting at a different reaction mechanism. Further, studies on a qNOR from a different host showed that qNOR is indeed electrogenic. This surprising result opens up new discussions on the evolution of oxygen and nitric oxide reductases, and about how energy conservation can be achieved.

  • Disputas: 2017-11-10 10:00 Vivi Täckholmsalen (Q-salen), NPQ-huset, Stockholm
    Woronik, Alyssa
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    A functional genomic investigation of an alternative life history strategy: The Alba polymorphism in Colias croceus2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Life history traits affect the timing and pattern of maturation, reproduction, and survival during an organism’s lifecycle and are the major components influencing Darwinian fitness. Co-evolved patterns of these traits are known as life history strategies (LHS) and variation occurs between individuals, populations, and species. The polymorphisms underlying LHS are important targets of natural selection, yet the underlying genes and physiological mechanisms remain largely unknown. Mapping the genetic basis of a LHS and subsequently unraveling the associated physiological mechanisms is a challenging task, as complex phenotypes are often polygenic. However, in several systems discrete LHS are maintained within the population and are inherited as a single locus with pleiotropic effects. These systems provide a promising starting point for investigation into LHS mechanisms and this thesis focuses on one such strategy - the Alba polymorphism in Colias butterflies. Alba is inherited as a single autosomal locus, expressed only in females, and simultaneously affects development rate, reproductive potential, and wing color. Alba females are white, while the alternative morph is yellow/orange. About 28 of 90 species exhibit polymorphic females, though whether the Alba mechanism and associated tradeoffs are conserved across the genus remains to be determined. In this thesis I primarily focus on the species Colias croceus and integrate results from lipidomics, transcriptomics, microscopy, and genomics to gain insights to the proximate mechanisms underlying Alba and Alba’s evolution within the genus. Lipidomics confirm that, consistent with findings in New World species, C. croceus Alba females have larger abdominal lipid stores than orange, an advantage which is temperature dependent and arises primarily due to mobilized lipids. Gene expression data suggests differences in resource allocation, with Alba females investing in reproduction rather than wing color, consistent with previous findings in other Colias species. Additionally, I identify a morphological basis for Alba’s white wing color. Alba females from C. croceus, an Old World species, and Colias eurytheme, a New World species both exhibit a significant reduction in pigment granules, the structures within the wing scale that contain pigment. This is a trait that seems to be unique to Colias as other white Pierid butterflies have an abundance of pigment granules, similar to orange females. I also map the genetic basis of Alba to a single genomic region containing an Alba specific, Jockey-like transposable element insertion. Interestingly this transposable element​ is located downstream of BarH-1, a gene known to affect pigment granule formation in Drosophila. Finally, I construct a phylogeny using a global distribution of 20 Colias species to facilitate investigations of Alba’s evolution within the genus.

  • Disputas: 2017-11-10 10:00 De Geersalen, Geovetenskapens hus, Stockholm
    Weidenstedt, Linda
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Sociologiska institutionen.
    A Sociology of Empowerment: The Relevance of Communicative Contexts for Workplace Change2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Empowerment has been a popular concept in management and leadership practice and research for more than forty years. The intentions behind empowerment at the workplace are positive: empowered employees should experience a greater degree of influence, decision-making latitude, and meaningfulness. This is achieved through transfers of power, such as increases in autonomy and responsibility. Although empowerment efforts have often been shown to successfully result in empowered and highly involved employees, there has also been research that shows the opposite: the so-called paradox of empowerment is a well-known problem that refers to failed empowerment efforts through which beneficiaries feel disempowered rather than empowered.

    This thesis comprises three papers intended to contribute to empowerment research and practice within a sociological framework that offers a better understanding of implicit assumptions between employer and employee and the unintended consequences these can have on the outcome of empowerment change efforts. The analyses utilize a communicative approach in line with sociological and social-psychological theories of communication and interaction.

    The first two papers are theoretical analyses, one examining the general concept of empowerment (Paper I), the other focusing more specifically on empowerment in workplace contexts (Paper II). Paper III is an empirical analysis that investigates some of the theoretical assumptions made in Papers I and II.

    The first paper analyzes empowerment from a sociological point of view and identifies possible mechanisms behind the paradox of empowerment. It is argued that such paradoxes may evolve from discrepancies between approaching empowerment from a purely economic and structural perspective versus a communicative and relational one. It concludes with the observation that, although their agency may be increased on a structural level, empowerees may experience a parallel decrease of agential options on a communicative level.

    The second paper deals with empowerment at the workplace as a management or leadership technique. Focusing on relational aspects, a “basic communicative structure” is identified. This is analyzed as comprising a contractual and a communicative context that should be taken into consideration by empowerers in order to avoid misunderstandings in the recipients’ sensemaking processes. Paper II concludes by arguing that the way recipients make sense of their roles and situations as defined by employment and/or psychological contracts might not necessarily be in line with the communicative meanings they ascribe to the change agents’ actions, and vice versa.

    The third paper analyzes employees’ orientations and attitudes toward empowerment and the relevance of their attitudes for the success of empowerment efforts. These issues are explored by means of survey data from 268 employees in the Swedish retail sector. Results indicate that age and work intensity (part-time vs. full-time), as well as cohabitation status may have significant impacts on how empowerment efforts are approached and received by employees.

    The thesis as a whole provides insights into sociological issues of empowerment, both generally and particularly in management and leadership contexts and concludes that the communicative context of empowerment interactions plays a significant role in employees’ empowerment orientations.

  • Disputas: 2017-11-10 10:00 Högbomsalen, Stockholm
    Szabo, Attila
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik.
    Mathematical abilities and mathematical memory during problem solving and some aspects of mathematics education for gifted pupils2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis reports on two different investigations.

    The first is a systematic review of pedagogical and organizational practices associated with gifted pupils’ education in mathematics, and on the empirical basis for those practices. The review shows that certain practices – for example, enrichment programs and differentiated instructions in heterogeneous classrooms or acceleration programs and ability groupings outside those classrooms – may be beneficial for the development of gifted pupils. Also, motivational characteristics of and gender differences between mathematically gifted pupils are discussed. Around 60% of analysed papers report on empirical studies, while remaining articles are based on literature reviews, theoretical discourses and the authors’ personal experiences – acceleration programs and ability groupings are supported by more empirical data than practices aimed for the heterogeneous classroom. Further, the analyses indicate that successful acceleration programs and ability groupings should fulfil some important criteria; pupils’ participation should be voluntary, the teaching should be adapted to the capacity of participants, introduced tasks should be challenging, by offering more depth and less breadth within a certain topic, and teachers engaged in these practices should be prepared for the characteristics of gifted pupils.

    The second investigation reports on the interaction of mathematical abilities and the role of mathematical memory in the context of non-routine problems. In this respect, six Swedish high-achieving students from upper secondary school were observed individually on two occasions approximately one year apart. For these studies, an analytical framework, based on the mathematical ability defined by Krutetskii (1976), was developed. Concerning the interaction of mathematical abilities, it was found that every problem-solving activity started with an orientation phase, which was followed by a phase of processing mathematical information and every activity ended with a checking phase, when the correctness of obtained results was controlled. Further, mathematical memory was observed in close interaction with the ability to obtain and formalize mathematical information, for relatively small amounts of the total time dedicated to problem solving. Participants selected problem-solving methods at the orientation phase and found it difficult to abandon or modify those methods. In addition, when solving problems one year apart, even when not recalling the previously solved problem, participants approached both problems with methods that were identical at the individual level. The analyses show that participants who applied algebraic methods were more successful than participants who applied particular methods. Thus, by demonstrating that the success of participants’ problem-solving activities is dependent on applied methods, it is suggested that mathematical memory, despite its relatively modest presence, has a pivotal role in participants’ problem-solving activities. Finally, it is indicated that participants who applied particular methods were not able to generalize mathematical relations and operations – a mathematical ability considered an important prerequisite for the development of mathematical memory – at appropriate levels.

  • Disputas: 2017-11-10 13:00 William-Olssonsalen, Stockholm
    Morlanes, José Igor
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Statistiska institutionen.
    Some Extensions of Fractional Ornstein-Uhlenbeck Model: Arbitrage and Other Applications2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This doctoral thesis endeavors to extend probability and statistical models using stochastic differential equations. The described models capture essential features from data that are not explained by classical diffusion models driven by Brownian motion.

    New results obtained by the author are presented in five articles. These are divided into two parts. The first part involves three articles on statistical inference and simulation of a family of processes related to fractional Brownian motion and Ornstein-Uhlenbeck process, the so-called fractional Ornstein-Uhlenbeck process of the second kind (fOU2). In two of the articles, we show how to simulate fOU2 by means of circulant embedding method and memoryless transformations. In the other one, we construct a least squares consistent estimator of the drift parameter and prove the central limit theorem using techniques from Stochastic Calculus for Gaussian processes and Malliavin Calculus.

    The second phase of my research consists of two articles about jump market models and arbitrage portfolio strategies for an insider trader. One of the articles describes two arbitrage free markets according to their risk neutral valuation formula and an arbitrage strategy by switching the markets. The key aspect is the difference in volatility between the markets. Statistical evidence of this situation is shown from a sequential data set. In the other one, we analyze the arbitrage strategies of an strong insider in a pure jump Markov chain financial market by means of a likelihood process. This is constructed in an enlarged filtration using Itô calculus and general theory of stochastic processes.

  • Disputas: 2017-11-10 13:00 Nordenskiöldsalen, Geovetenskapens hus, Stockholm
    Eikje Ramberg, Linn
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur.
    Mynt er hva mynt gjør: En analyse av norske mynter fra 1100-tallet: produksjon, sirkulasjon og bruk2017Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    The kings of Norway issued coins on a regular basis starting in the mid-11th century, and probably conducted renovatio monetae whenever a new king came to power. As a privilege of bona regalia, the king could use coin production to serve his own interests. Economic factors are usually the main focus of discussions on coinage, but there were also political, religious and cultural dimensions that must have been important both for the production of coins and in the choice of motives, form and style. From the outset, manipulation of the coinage is visible in the debasement of silver content, followed by a reduction in weight to re-establish the silver level.  In the 12th century, the weights continued to drop and single-faced coins and bracteates became the standard; only a few biface coins are known.

    These small coins and bracteates from the 12th century carry little or no information concerning issuer, date or place of production. This lack of information has resulted in a gap in our knowledge about the role of these coins in medieval society in Norway. This role was dependent both on the intentions of the producer and on how the coins were perceived by the people, and their will to use them in certain ways. What were the reasons behind issuing the smallest coins ever produced in coin history, and what impact did this dramatic reduction in weight have on the understanding and use of the coin?

    To advance the discussion it has been vital to establish new knowledge about chronology, coin-issuing authority and mints. These areas have been addressed through two analyses using numismatic and archaeological methods. The results of the initial analyses are combined with an investigation of the size of the coin production and a study of archaeological contexts, in order to reveal how, where and when the bracteates were used. 

    The theoretical approach to understanding the role of coins is inspired by theories in anthropology and sociology about the many ways in which money can be incorporated in a society, emphasising the complex social component of coins in contrast to the traditional economic emphasis on their neutral qualities as a means of exchange. Central to this are the concepts behind formalism and substantivist and post-substantivist theory. The study concludes with a discussion that explores what can be said about economy and economic systems based on the 12th-century Norwegian coins.

  • Disputas: 2017-11-10 14:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Guala, Dimitri
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik. Stockholm, Bioinformatics Center, Science for Life Laboratory.
    Functional association networks for disease gene prediction2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Mapping of the human genome has been instrumental in understanding diseasescaused by changes in single genes. However, disease mechanisms involvingmultiple genes have proven to be much more elusive. Their complexityemerges from interactions of intracellular molecules and makes them immuneto the traditional reductionist approach. Only by modelling this complexinteraction pattern using networks is it possible to understand the emergentproperties that give rise to diseases.The overarching term used to describe both physical and indirect interactionsinvolved in the same functions is functional association. FunCoup is oneof the most comprehensive networks of functional association. It uses a naïveBayesian approach to integrate high-throughput experimental evidence of intracellularinteractions in humans and multiple model organisms. In the firstupdate, both the coverage and the quality of the interactions, were increasedand a feature for comparing interactions across species was added. The latestupdate involved a complete overhaul of all data sources, including a refinementof the training data and addition of new class and sources of interactionsas well as six new species.Disease-specific changes in genes can be identified using high-throughputgenome-wide studies of patients and healthy individuals. To understand theunderlying mechanisms that produce these changes, they can be mapped tocollections of genes with known functions, such as pathways. BinoX wasdeveloped to map altered genes to pathways using the topology of FunCoup.This approach combined with a new random model for comparison enables BinoXto outperform traditional gene-overlap-based methods and other networkbasedtechniques.Results from high-throughput experiments are challenged by noise and biases,resulting in many false positives. Statistical attempts to correct for thesechallenges have led to a reduction in coverage. Both limitations can be remediedusing prioritisation tools such as MaxLink, which ranks genes using guiltby association in the context of a functional association network. MaxLink’salgorithm was generalised to work with any disease phenotype and its statisticalfoundation was strengthened. MaxLink’s predictions were validatedexperimentally using FRET.The availability of prioritisation tools without an appropriate way to comparethem makes it difficult to select the correct tool for a problem domain.A benchmark to assess performance of prioritisation tools in terms of theirability to generalise to new data was developed. FunCoup was used for prioritisationwhile testing was done using cross-validation of terms derived fromGene Ontology. This resulted in a robust and unbiased benchmark for evaluationof current and future prioritisation tools. Surprisingly, previously superiortools based on global network structure were shown to be inferior to a localnetwork-based tool when performance was analysed on the most relevant partof the output, i.e. the top ranked genes.This thesis demonstrates how a network that models the intricate biologyof the cell can contribute with valuable insights for researchers that study diseaseswith complex genetic origins. The developed tools will help the researchcommunity to understand the underlying causes of such diseases and discovernew treatment targets. The robust way to benchmark such tools will help researchersto select the proper tool for their problem domain.