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  • 1.
    Shevtsov, Stepan
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM). KU Leuven, Belgium.
    A Control-theoretic Approach to Realize Self-adaptive Software Systems with Guarantees2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Engineering modern software systems is a challenging task as these systems are subject to different types of uncertainties. Examples of such uncertainties are disturbances in the environment that are difficult to predict and goals that may change during operation. The idea of self-adaptation is to handle these uncertainties at runtime, when the knowledge becomes available to resolve them. As more software systems with strict requirements are designed to be self-adaptive, the need for adaptation guarantees is becoming a high-priority concern. Providing such guarantees with traditional architecture-based approaches has shown to be challenging, calling for new approaches to engineer self-adaptive systems. To tackle this challenge, this thesis studies control-based software adaptation (CBSA). CBSA applies principles from control theory to design self-adaptive software systems. More specifically, we address the following research problem using CBSA: how to realize self-adaptive software systems that satisfy multiple stakeholder requirements with guarantees in the presence of uncertainties.

    The thesis addresses the research problem in two subsequent stages. The first stage focuses on satisfying multiple stakeholder requirements of different types, and providing adaptation guarantees. This stage starts with a systematic literature review of CBSA, which provides a comprehensive overview of the field, including existing CBSA approaches, applied models and controllers, and analyzed guarantees. From the review, we identify a number of gaps in the existing research and concrete challenges in addressing the research problem. Then, we devise SimCA, a control-theoretic approach to realize self-adaptive software systems that satisfy multiple requirements with guarantees. SimCA combines mathematical models of software system, a control-based adaptation mechanism, and formal analysis of the required guarantees. SimCA is also reusable, meaning that it can be applied to a family of cooperative software systems with strict requirements. The second research stage focuses on handling different types of uncertainty.We first discuss the types of uncertainty and study whether existing CBSA approaches try to deal with these types. We then introduce an enhanced approach called SimCA* that includes components to deal with uncertainty in software parameters, addition or removal of requirements at runtime and software component interactions. In order to obtain evidence about the applicability and reusability of SimCA and SimCA*, we apply informal exploratory case studies with three software systems with strict requirements from different domains.

  • 2.
    Rahman, Mohammad A.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Biophysical studies of the actin-myosin motor system and applications in nanoscience2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The actin-myosin motor system plays important roles in cellular processes. In addition, actin and myosin have been used for developments towards nanotechnological applications in recent years. Therefore, fundamental biophysical studies of actin and myosin and the actomyosin force generating cycle are important both in biology and for nanotechnology where the latter applications require methodological insights for optimization. This dual goal is central in the present thesis with major focus on factors that control the function (e.g. velocity) and the effectiveness of transport of filaments (e.g. filament flexural rigidity) through nanoscale channels with supplementation of methodological insights. The thesis thus provides evidence that actin is a dynamic filament whose flexural rigidity is different at different MgATP concentrations as well as in the presence or absence of myosin binding. Furthermore, probing the myosin ATPase cycle with the myosin inhibitor blebbistatin revealed that velocity is easily modified by this drug. Our detailed studies also suggest that actin-myosin force generation is preceded by Pi release and that blebbistatin changes the rate limiting transition in the cycle from the attachment step to a step between weakly attached states. The studies of actin dynamics and of the actomyosin force generating cycle were largely performed using in vitro motility assay (IVMA) where surface adsorbed myosin motor or its proteolytic fragments propel fluorescently labeled actin filaments. The IVMA is often taken as the basis for developments towards different nanotechnological applications. However, in the IVMA, actomyosin motility is often negatively affected by the presence of “dead”, non-functional myosin heads. Therefore, in this thesis, two popular methods, that are often used to remove dead myosin heads, are analyzed and compared. It was found that after affinity purification, the in vitro actin sliding velocity is reduced compared to the control conditions, something that was not seen with the use of blocking actin. Therefore, the effects of the affinity purification method should be considered when interpreting IVMA data. This is important while using IVMA both for fundamental studies and for nanotechnological applications. Another issue in the use of IVMAs in nanotechnological applications is the requirement for expensive and time-consuming fabrication of nanostructured devices. We therefore developed a suitable method for regenerating molecular motor based bionanodevices without a need to disassemble the flow cell. Evidence is presented that, use of proteinase K with a suitable detergent (SDS or Triton X100) lead to successful regeneration of devices where both actin-myosin and microtubule-kinesin motility are used. Lastly, this thesis presents efforts to immobilize engineered light sensitive myosin motors on trimethyl chlorosilane (TMCS) derivatized surfaces for light operated switching of myosin motor in order to control actin movement in nano-networks. This has potential for developing a programmable junction in a biocomputation network. In brief, the described results have contributed both to the fundamental understanding of actin and myosin properties and the actomyosin interaction mechanisms. They have also given technical insights for molecular motor based bionanotechnology.

  • 3.
    Sjökvist, Tinh
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Coated Norway Spruce: Influence of Wood Characteristics on Water Sorption and Coating Durability2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Wood used outdoors is often degraded and discoloured by microorganisms as a natural part of its life cycle, particularly when exposed to high levels of moisture for prolonged times. In this case, the application of a coating (i.e. paint) is an option for increasing the service life of the wood.

    Norway spruce (Picea abies (L.) Karst.) is commonly used for outdoor applications in Sweden. Earlier studies have shown that uncoated spruce heartwood is less prone to moisture sorption in outdoor exposure, resulting in lower moisture content (MC) levels, as compared to sapwood. However, studies related to the above mentioned characteristics are rather limited for coated spruce, especially including the influence of outdoor exposure (i.e. weathering).

    The aim of this thesis is, therefore, to increase the knowledge of how heartwood and sapwood of different densities influence on the durability of coated Norway spruce for outdoor use. Different types of coatings with alkyd-, acrylic-, flour- (calcimine paint), or linseed-oil-based resin were included. The objectives were to study the water sorption (including MC variation) behaviour and crack formation of uncoated and coated heartwood and sapwood of different densities.

    Furthermore was an objective to study the microbial growth on the surface of similar samples of coated spruce in outdoor exposure. The used methods included wetting and liquid permeability experiments, accelerated water absorption (with samples floating freely in water), and outdoor field test. The field method lasted between three to five years and involved monitoring of the MC variation, the crack formation and the microbial growth on the samples.

    The results based on wetting measurements using octane as the adsorbed liquid showed no difference in liquid permeability between the spruce heartwood and sapwood samples of comparable densities, and indicated a similar level of pit aspiration (closure). The common flow path between two cells of conifers occurs through the pits. Still, the sapwood samples had in general a clearly higher water sorption rate than heartwood samples. It could be concluded that the increased sorption was presumably caused by a lowered water surface tension, most likely by a contamination effect of the water by surface-active sapwood extractives rather than differences in morphology of heartwood and sapwood.

    However, no clear difference in water absorption and MC levels was seen between coated heartwood and sapwood in the field study or in the accelerated water absorption study. Thus, it is suggested that a coating hinders the surfaceactive extractives to lower the water surface tension, resulting in a similar water absorption behaviour of coated heartwood and sapwood. The influence of density on water sorption of coated spruce was similarly to uncoated spruce, meaning the low-density samples had a higher MC than the high-density samples in the field tests. Furthermore, a one-year weathering of the coated and uncoated samples caused a larger increase in water sorption of high-density heartwood in the accelerated water absorption study.

    The field study on uncoated and calcimine-coated spruce showed a higher number of cracks on the high-density samples than on the low-density samples. Additionally, within each density group, a larger number of cracks were seen on sapwood samples as compared to heartwood samples. High-density samples with an alkyd- or an acrylic coating also showed a higher number of cracks. As expected, the formation of cracks on the samples increased their water sorption significantly. The microbial growth was higher on sapwood than on heartwood samples with a white coloured alkyd coating.

    The main conclusion is that heartwood and sapwood of different densities influence the water sorption and durability of coated Norway spruce. However, the principles in water sorption of uncoated heartwood and sapwood could not be applied to coated samples. Overall, the results point out that low-density heartwood could be the best material combination to improve the durability of coated spruce in outdoor use. The knowledge acquired in this thesis can enable an increased service life of coated spruce in outdoor use. The increase in service life is achieved by a careful selection of the wood material regarding the proportion of heartwood and to the choice of wood density. As a concluding remark, the role of surface-active spruce extractives needs to be explored, and a follow-up investigation in the context of water sorption is suggested for future research.

  • 4.
    Waxegård, Gustaf
    Linnaeus University, Faculty of Health and Life Sciences, Department of Psychology.
    Conceptualizing professionals' strategies in care pathways for neurodevelopmental disorders2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Neurodevelopmental disorders (ND), are complex neuropsychological functional impairments. About 3-5% of all children meet criteria for attention deficit and hyperactivity disorder (ADHD), and about 1% for autism spectrum disorder – along with intellectual developmental disorder the most common ND diagnoses. Degree and type of functional impairment vary greatly within and between patients, necessitating multi-professional assessment and treatment. Using classic grounded theory (Glaser), this thesis offers a new theory of professionals’ practices in care pathways for ND. It also contains a pilot evaluation of a new, tablet-based, clinical test of attention.

    Study I shows that care pathways for ND are characterized by social dilemmas. What is rational for an individual professional, team or clinic, is not always rational for the care pathway as a whole. Collective action therefor requires development and sustainability of inter-professional trust. The study highlights strategies used by professionals to decide on whether to act collectively or unilaterally. Such trust testing strategies are couched in the frameworks of social dilemma-theory and game-theory.  

    Study II emphasizes the importance of professional control over strategies, structures and methods in the care pathway for ND (unpacking control) to deal with ND-related complexity. Lack of such control can short-circuit the ability to work successfully as a professional. Unpacking control is understood mainly in the light of professions theory.

    Study III evaluates the new MapCog Spectra test as a rapid method to detect and assess clinical problems of attention. Four groups of children and adolescents took the test. Two groups were comprised of patients with either ND or other psychiatric problems. Two groups were comprised of school children without known clinical conditions. The MapCog Spectra test separated clinical from non-clinical groups with good precision.

    In the thesis, concepts from studies I and II are integrated and extended to form a unified theory about professional practices in care pathways for ND. The latters are suggested to be a particular form of commons, which can be collectively managed by professionals in more or less successful ways. A quantitative model for the dynamics in the care pathways is presented.

  • 5.
    Jonsdottir, Sigridur Sia
    Linnaeus University, Faculty of Health and Life Sciences, Department of Health and Caring Sciences.
    Effects of perinatal distress, satisfaction in partner relationship and social support on pregnancy and outcome of childbirth2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Aim: The aim of this thesis was to achieve a deeper understanding of the situation among women experiencing perinatal distress during pregnancy and childbirth and the effects that dissatisfaction in partner relationship and weak social support from family and friends could have on pregnancy and childbirth.

    Methods: Following screening for perinatal distress, 562 expecting mothers came for a semi-structured interview. This screening, done with the Depression Anxiety Stress Scales and the Edinburgh Postpartum Depression Scale, categorized 360 (64.1%) women into the perinatal distressed group (PDG) and 202 (35.9%) into the non-distressed group (NDG). During the interview women answered the Dyadic Adjustment Scale and the Multidimensional Scale of Perceived Social Support. Data were collected with these instruments for study I. Additional data for the three other studies were gathered from the women´s pregnancy records (II), electronic medical records (II, III), and childbirth records (IV). Results of the four studies were obtained by using descriptive statistics; parametric and nonparametric statistics and regression modeling.

    Results: Women in the PDG were significantly more likely than the NDG to be dissatisfied in their partner relationship, continue smoking during pregnancy, be dissatisfied with division of household tasks and child-rearing, have elementary or lower education, and to be students or unemployed. They were also significantly more likely to experience fatigue, vomiting and pelvic girdle pain during pregnancy. Women in the PDG who received weak family support reported nausea and heartburn more frequently than those with strong family support. Women in the PDG utilized more antenatal care service and were allocated more part time as well as earlier sick leaves during pregnancy, than those in the NDG. Women in the PDG were significantly more likely to use epidural anesthesia as a single pain management during labor.

    Conclusion: Perinatal distress affects pregnancy and childbirth. It is more common among women who are dissatisfied in their partner relationship and with the division of household tasks and child-rearing. Perception of weak social support also affects pregnancy among distressed women. Distressed women along with their partners and families should be offered support and consultation to relieve distress and strengthen their bonds during pregnancy and childbirth.  

  • 6.
    Zimmer, Björn
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Guided Interaction and Collaborative Exploration in Heterogeneous Network Visualizations2019Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The visual exploration of large and complex network structures remains a challenge for many application fields, such as systems biology or social sciences. Often, various domain experts would like to work together to improve the analysis time or the quality of the analysis results. Collaborative visualization tools can facilitate the analysis process in such situations. Moreover, a growing number of real world networks are multivariate and often interconnected with each other. Entities in a network may have relationships with elements of other related data sets, which do not necessarily have to be networks themselves, and these relationships may be defined by attributes that can vary greatly. A challenge is to correctly assign the attributes and relations between different data sets and graphs in order to be able to analyze them visually afterwards. The navigation between the resulting visualizations is also difficult. How can users be guided to other interesting data points relevant to their current view and how can this information be additionally displayed in a graph without losing the overview of the data?

    In this dissertation, we propose our new web-based visualization environment OnGraX, which supports distributed, synchronous and asynchronous collaboration of networks and related multivariate data sets. In addition to standard collaboration features like event tracking or synchronizing, our client/server-based system provides a rich set of visualization and interaction techniques for better navigation and overview of the input network. Changes made by specific analysts or even just visited network elements can be highlighted by heat maps, which enable us to visualize user behavior data without affecting the original graph visualization. We evaluate the usability of the heat map approach against two alternatives in a user experiment.

    Additional features of OnGraX include a comprehensive visual analytics approach that supports researchers to specify and subsequently explore attribute-based relationships across networks, text documents, and derived secondary data. Our approach provides an individual search functionality based on keywords and semantically similar terms over an entire text corpus to find related network nodes. For examining these nodes in the interconnected network views, we introduce a new interaction technique, called Hub2Go, which facilitates the navigation by guiding the user to the information of interest. To showcase these features, we use a large text corpus collected from papers listed in the IEEE VIS publications data set (1990--2015) that consists of 2,752 documents. We analyze relationships between various heterogeneous networks, a Bag-of-Words index, and a word similarity matrix, all derived from the initial corpus and metadata. We also propose a design for the interactive specification of degree-of-interest functions, which can be used to provide and evaluate configurations for guidance based on network attributes and logged user data in heterogeneous networks.

  • 7.
    Eklund, Andreas
    Linnaeus University, School of Business and Economics, Department of Marketing.
    Harmonising value in a car’s interior using sensory marketing as a lens2019Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The human senses have always influenced people’s perceptions of thesurrounding environment and objects. As a consequence of the evolvement ofthe experience economy, research on the human senses has increasedsubstantially and attracted scholars from various research domains, includingsensory marketing. In the marketing domain, research emphasises that value iscreated when consumers experience brands, products, and servicescapes that areexciting and fun to interact with through the human senses. In accordance withthe service-dominant logic discussion, value is created from the servicesurrounding the product, such as the experience, which includes manufacturersand consumers. Although this has partly been captured under sensorymarketing, little is known of how sensory marketing cues contribute to brandexperience and brand value. Theoretically, it is emphasised that creating valueis a service process, where the manufacturer’s goal is to plan and design amultisensory brand experience facilitated by the human senses leading toconsumer value, as well as to enhance the brand as an image. Hence, the purposeof this dissertation is to understand and explain how value is created within acar’s interior by applying sensory marketing as a lens.

    To address the purpose, an exploratory sequential mixed methods approachwas employed to capture different aspects of creating value. The empirical dataare based on a case study with a global premium car manufacturer, focusing onhow value is created and offered within a car’s interior. The qualitative sequenceexplored how the manufacturer plans and designs a value proposition byembedding sensory cues in the car’s interior. Furthermore, how value-in-use iscreated by providing a brand experience is analysed. The quantitative sequenceexamined the relationship between brand experience and brand image to explainhow consumer value as an experience is created.

    The dissertation concludes that creating value in the car’s interior followsthe logic of service-dominant logic and includes manufacturers and consumers.For the manufacturer, this was a strategic process to position the automotivebrand as premium by offering value in the car’s interior. To achieve this, valuewas planned and designed by embedding sensory cues in the car’s interior.However, sensory cues were not embedded in isolation; rather they wereharmonised with another to gestalt the coherent theme of Scandinavia in termsof colour, material, and shape to provide consumers with a brand experience forsense-making. Moreover, it was demonstrated that not all brand experiencedimensions impact brand image to create value as an experience. The resultsshow that sensory, affective, and harmony experience have a positiverelationship with brand image, which generates the consumer’s value as anexperience.

    Overall, the dissertation contributes to the process of creating value in thecar’s interior by relating sensory marketing with branding and service-dominantlogic, with harmony uniting these. Similar to an orchestra, where the conductorstrategically organises various instruments on the stage to play a harmoniousmelody for the audience, the manufacturer uses the car’s interior as a stage withsensory cues to provide consumers with a harmonious brand experience, leadingto a positive brand image. Harmony has been identified, operationalised,measured, and tested with a positive result. Theoretical, managerial, and ethicalimplications are discussed.

  • 8.
    Lindblad, Fredrik
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Identifying drivers and barriers for market growth within the industry producing wooden multi-family houses: Land allocation process for future growth2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    At present, Sweden is experiencing a housing shortage, which Swedish authorities expect to continue until at least 2025. Producers of wooden multi-family houses have a relatively small market share compared to those who use traditional building materials. Limited ability to meet the increased building demand restricts possibilities for development regarding innovation, bio-economy and sustainability.

     

    Swedish municipalities are responsible for planning the building development in their regions based on their projected requirements and strategies. Combining this with a desire to develop sustainable building solutions based on wood increases complexity in the public procurement process. Currently, public building developments are achieved through the Public Procurement Act or land-allocation activity, depending on the development strategy. This normally involves developing local strategies regarding, e.g. design, material choice and geographical development. Identifying drivers and barriers in the industry and market enables improved market entry activities related to public building initiatives using wood-based solutions. Hence, improving transparency in land-allocation activity generates possibilities for companies to respond successfully to requests from municipalities. This knowledge is used to better understand the required strategic development for companies, the government and municipalities to increase use of sustainable building materials such as wood in Swedish multi-family housing projects.

     

    Results show that the industry experiences barriers associated with municipalities' actions and knowledge related to wood as a building solution. Further, concrete’s strength as a building material is an issue, since municipalities tend to opt for familiar solutions. Furthermore, the way in which municipalities manage land-allocation activity is perceived as insufficient, with limited information, a subjective evaluation process, and uncertainties regarding their roles in the process. These factors contribute to ambiguity and sub-optimisation for developers proposing wood-based building solutions.

  • 9.
    Johansson, Maria
    Linnaeus University, Faculty of Health and Life Sciences, Department of Health and Caring Sciences.
    Intensivvårdsdagbok i Sverige: betydelse och tillämpning2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Aim: The overall aim of the thesis was to explore how the Intensive Care Unit (ICU) diary was experienced by family members, family members of non-survivors and nursing staff in the ICU setting, thereby contributing to the development of national clinical practice guidelines regarding the structure, content and use of the ICU diary.

    Methods:  A qualitative design was employed for all four studies:  a hermeneutic approach was adopted in studies I and II, whilst a qualitative descriptive design with the use of focus groups interviews was chosen in study III. An Instrumental Multiple Case Study design was carried out in study IV.

    Main Findings: The diary symbolised the maintenance of relationships with the patients and was a substitute for the usual opportunities for communication. The diary was instrumental in meeting the needs of the majority of participant family members. The diary provided the means to be present at the patient’s bedside, to feel involved in caregiving, to maintain hope and to relay relevant information. If the critically ill family member did not survive the stay in the ICU, the diary acted as a form of bereavement support by processing the death of the patient. Nevertheless, some family members found the diary too public an arena to write in as the diary entries indicated visiting patterns which in turn provoke feelings of guilt when the visits were infrequent. Further, not knowing what to write was another source of pressure.

    Nursing staff experienced that writing diaries often felt meaningful and led to an increased motivation and engagement in patient care and family support. They expressed that they felt they did something good for the patient and family members. Thus, the diary can be seen as a way to promote person-centred care, where family members were offered to participate in the care. However, in the absence of guidelines or clear guidelines about the use of an ICU diary, then not many patients actually received a diary.

    Conclusions: Practice guidelines concerning ICU diaries would help to ensure the more widespread and consistent use of diaries for all ICU patients. As family members may benefit from the diary, even if the patient may not always be able to do so. The ICU diary can be seen as a tool to help promote person-centred care by directly involving family members and providing a human touch, thus helping to counterbalance the highly technical physical environment of ICU.

  • 10.
    Hanell, Fredrik
    Lund University, Sweden.
    Lärarstudenters digitala studievardag: Informationslitteracitet vid en förskollärarutbildning2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This dissertation reports on an investigation into how digital tools are used, negotiated and given meaning in Swedish pre-school teacher education. The overall aim has been to create a deeper understanding of how students’ information literacies are enacted when digital tools are used and appropriated in the daily life at a pre-school teacher education, in relation to conceptions of the digitalisation of teacher education in national policy. A netnographical study at a pre-school teacher education was conducted between 2012 and 2015. The study generated online material, mainly from a Facebook Group used by students and teacher, and field notes from participant observations, transcribed interviews and a field diary. Through application of a socio-cultural perspective on information literacy, the netnographical material was analysed using the concepts appropriation and identity. To analyse the discursive level, four national policy documents with demands for increased digital competence in teacher education were analysed using Carol Bacchi’s ‘what’s the problem represented to be?’ approach.

    The findings show how views on learning and identity interact with the materiality of the digital tools and the enabling and constraining properties of the local learning environment when information literacies are enacted. The identity position discussion-oriented student is connected to how the Facebook Group is appropriated as a relation-building tool and a relational information literacy. This type of information literacy entails a view on learning as co-learning, rooted in the historical development of pre-school teacher education, and a non-hierarchical understanding of teacher and student roles. The identity positions goal-oriented student and customer-oriented student are connected to how the Facebook Group is appropriated as a collaborative problem-solving tool and a pragmatic information literacy. This form of information literacy reflects instrumental and neoliberal views on learning, and a traditional understanding of teacher and student roles. The policy analysis shows how an economic and competitive perspective underpins demands for increased digital competence in teacher education, and how the value of digital tools for learning and teaching is taken for granted. The idea of co-learning, that is found to be influential but not fully accepted at the pre-school teacher education, is difficult to combine with an economic perspective emphasising measurability and quantification. The economic perspective is partly compatible with a pragmatic information literacy. The findings of the dissertation shed light on the gap between what is described as important in policy documents and what teacher students and teachers describe as important when digital tools are used in teacher education.

  • 11.
    Sjöstrand Öhrfelt, Magdalena
    Linnaeus University, Faculty of Social Sciences, Department of Education and Teacher's Practice.
    Ord och inga visor: konstruktioner av förskolebarnet i kunskapsekonomin2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Historically, changes in preschool policy have been legitimized in relation to ideas about the preschool child and the various problems that the education of this child is supposed to be able to “solve”. From an early age, children have been considered the most effective tool for dealing with a variety of social, economic or environmental issues of central importance for maintaining and developing society.

    Against this background, the purpose of this thesis is to examine representations of the preschool child in different policy texts (textbooks, research- and educational policy) related to changing requirements and targets affecting contemporary Swedish preschools. Discursive constructions of the preschool child are considered as important central aspects, used to legitimize political reforms in accordance with pedagogical ideas and prevailing social contexts. The thesis focuses on the tensions within contemporary constructions of the preschool child in the so-called “knowledge economy”: i.e. the tensions between a competent child, who is both able and willing to take advantage of education, and a “newcomer” – the vulnerable child – in need of obtaining the benefits of education in order to be able to cope with the future.

    The simultaneously competent and vulnerable preschool child is thus an efficiently designed target for the interests of economic transnational organizations viewing education mainly in terms of human capital development, as well as an important factor for economic competitiveness.

    In the thesis’ final analysis, I study how the OECD, EU and IEA are developing methods for measuring and evaluating the results of preschool education, with the intention of being able to "streamline" it by finding universally successful concepts that are both cost-effective and of high quality. The construction of the preschool child as simultaneously competent and vulnerable is used to legitimize shifts in power over the definition of the Swedish preschool agenda, the fundamental ideas of what preschool is about, what its aims are, and for whom it is intended. As these ideas are disguised as being the result of supposedly "objective" forces far from the ideological contradictions of the political sphere, a critical discussion concerning the goals and aims of early childhood education becomes almost impossible to achieve.

  • 12.
    Johansson, Maude
    Linnaeus University, Faculty of Health and Life Sciences, Department of Psychology.
    Postpartum depression, depressive symptoms and parental stress in mothers and fathers 25-30 months after child birth: A family perspective2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The overall aim of this thesis was to explore the prevalence of postpartum depression and parental stress 25 - 30 months after delivery. The first study was conducted 25 months after delivery. The aims were to investigate the prevalence of postpartum depression and the associations between postpartum depression and parental stress in two areas of study; spouse relationship problems and feelings of incompetence in parenthood. Seven hundred mothers and 646 fathers answered a questionnaire. The results showed that the prevalence of depressive symptoms was more than 11% for mothers and nearly 5% for fathers and that parents with postpartum depressive symptoms experienced more feelings of incompetence and spouse relationship problems than parents without postpartum depressive symptoms.

    The second study included 176 mothers and 146 fathers. The aims of the study were to determine the prevalence of postpartum depressive symptoms, and if parental stress and attachment style affected postpartum depression in mothers and fathers 30 months after birth. The prevalence rate of postpartum depressive symptoms in mothers was 14.9 %, while for fathers it was 11.5 %. We observed a difference with the preoccupied and fearful attachment style in terms of parents with postpartum depressive symptoms and parents without postpartum depressive symptoms. However, the differences were not significant. Furthermore, parental stress outperformed attachment styles as a predictor for postpartum depressive symptoms in both the mothers and the fathers.

    Study III was a qualitative interview study explored the lived experiences of mothers and fathers, their experiences of postpartum depression, and parental stress. Five prominent themes were identified. Both mothers and fathers described experiences of inadequacy as the most stressful. Experiences of problems during pregnancy or a traumatic delivery contributed to depressive symptoms and anxiety in mothers, and affected fathers’ wellbeing.

    Thus, identifying depressive symptoms with the Edinburgh Postnatal Depressive Scale (EPDS), mothers described varying experiences of child health care support. Depressive symptoms seemed to affect the spouses’ relationships. Experiences of emotional problems and insecure upbringing in the parents’ family of origin may contribute to vulnerability that led to long-term problems for mothers.

    The overall conclusion of this thesis was that postpartum depression and parental stress had a significant impact on the everyday lives and that postpartum depression does not seemed to decline 25- 30 months after childbirth.

  • 13.
    Thulin, Johanna
    Linnaeus University, Faculty of Social Sciences, Department of Social Work.
    Putting words to child physical abuse: Possible consequences, the process of disclosure, and effects of treatment. From children’s perspectives2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Aim: The overall aim of the thesis is to explore the experiences and possible consequences concerning reported health and relations between a parent perpetrator of physical child abuse and the children who are victims of the parental physical abuse, the children’s thoughts when disclosing the abuse, and the impact of an intervention designed to support these children in a Swedish context – Combined Parent Child Cognitive Behavioral Therapy (CPC-CBT). Methods: This thesis has a mix-method design. Study I and IV used different self-assessment scales, and the outcomes were analysed using descriptive statistics, paired-samples t test, independent t test, ANOVA, Pearson correlations, and hierarchical linear regression. Study II and III consisted of interviews with 15 (Study II) and 20 (Study III) children, respectively. The interviews were transcribed verbatim and analysed using qualitative content analysis. Results: The results suggest that experiencing child physical abuse affects the relationship between a parent and a child as well as the child’s wellbeing in several ways. However, the results also suggest that participating in the CPC-CBT intervention could decrease parents’ use of violence and increase the child’s wellbeing. In addition, the results suggest that trust and participation influence whether a child discloses abuse and contributes to the success of treatment. Conclusion: The CPC-CBT could be seen as a successful turning point for the participating children, shifting from one trajectory (living in fear of violence) to another (living without fear). Furthermore, when children disclose to adults about their physical abuse, it is important that the adults recognise the children’s participatory rights and strive to earn their trust.

  • 14.
    Ståhlkrantz, Katarina
    Linnaeus University, Faculty of Social Sciences, Department of Pedagogy and Learning.
    Rektors pedagogiska ledarskap: en kritisk policyanalys2019Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The pedagogical leadership is regarded as the most significant of the principal ́s duties. Because there is no clear definition of pedagogical leadership as a concept, it may be difficult for the principal to know how to practice it. Various versions of the concept’s meaning are currently circulating, in turn offering different norms to relate to and act upon. This doctoral thesis takes its point of departure from the policy proposal of a Rektorslyft in the Swedish national budget of 2011, as a solution to the problem that principals were not considered to be good enough pedagogical leaders. The study is designed as a critical policy analysis, with a curriculum theory framework and a critical interpretative perspective. The critical approach is directing focus towards the steering of the school. Further, a poststructuralist perspective adds a discursive approach to the study. The empirical material consists of a selection of official education policy documents, mainly governmental official reports. The aim of the study is to examine and analyse how the pedagogical leader is discursively constructed in official education government documents, what changes and stabilities can be distinguished in these discursive constructions over time and how these can be understood and explained. Bacchi ́s WPR-method and Foucault ́s genealogy is used as a methodological framework for the text analysis. The result shows six discursive breakpoints in the construction of the pedagogical leader from the 1950s to 2010s. These breakpoints have a close relationship to changes in school steering. Principals’ pedagogical leadership can therefore be regarded as a policy to legitimise new steering reforms. The result further indicates that principals from the 1950s to 2010s were given a clearer personal responsibility within the pedagogical leadership. The changes identified through the critical policy analysis can be explained by the context and policy streams. The text analysis also indicated stabilities in the discursive construction of the pedagogical leader. These stabilities can be explained by traditions and school structures. Hopefully, this study has contributed to a better and deepened understanding of principals’ pedagogical leadership, as well as have given the concept an empirical and theoretical basis.

  • 15.
    Svensson, Anders
    Linnaeus University, Faculty of Health and Life Sciences, Department of Health and Caring Sciences.
    Räddningsaktörers tidiga närvaro vid akuta situationer på svensk landsbygd2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Aim: The overall aim was to describe the first responders´ (FRs) experiences ofarriving early at emergency situations in rural areas in Sweden and the characteristicfeatures of the assignments they encounter. The four studies aimed to: describe critical incidents in which ambulance nurses experience worry in their professional life and the actions they take in order to prevent and cope with it (I), explore and describe experiences of the First Incident Person (FIP) assignment within an Fire Department (FD) (II), describe experiences of the While Waiting for the Ambulance (WWFA) assignment, as experienced by home healthcare nurses (III) and map out and describe WWFA assignments focusing on frequency, event time,CardioPulmonary Resuscitation (CPR) and survival >30 days after performed CPR (IV).

    Methods: The four studies in this thesis had both descriptive and explorative designs. They were analysed with qualitative and quantitative analysis methods.

    Results: By dispatching FRs in rural areas an early presence at the scene of anaccident or emergency situation can be secured, which prevent full scenarios to happen and increase the possibility to save lives. However, FRs are worried about specific emergency situations as well as situations related to their work environment.Leaving ongoing work tasks cause ethical dilemmas and inner emotional worries why support before, during and after an FR assignment is sought for.

    Conclusions: Generating effective interprofessional collaboration during FR assignment requires that the FRs work conditions are adopted to the assignment requirements for immediate response. The feeling of security disappears when the FRs are excluded from the group affiliation and the need to feel support in new interprofessional collaboration structures becomes clear. Support function based on individual requests is to be designed. Continuous collaborative exercises are required where all involved FRs participate.

  • 16.
    Kucher, Kostiantyn
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Sentiment and Stance Visualization of Textual Data for Social Media2019Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Rapid progress in digital technologies has transformed the world in many ways during the past few decades, in particular, with the new means of communication such as social media. Social media platforms typically rely on textual data produced or shared by the users in multiple timestamped posts. Analyses of such data are challenging for traditional manual methods that are unable to scale up to the volume and the variety of the data. While computational methods can partially address these challenges, they have to be used together with the methods developed within information visualization and visual analytics to gain knowledge from the text data by using interactive visual representations.

    One of the most interesting aspects of text data is related to expressions of sentiments and opinions. The corresponding task of sentiment analysis has been studied within computational linguistics, and sentiment visualization techniques exist as well. However, there are gaps in research on the related task of stance analysis, dedicated to subjectivity that is not expressible only in terms of sentiment. Research on stance is an area of interest in linguistics, but support by computational and visual methods has been limited so far. The challenges related to definition, analysis, and visualization of stance in textual data call for an interdisciplinary research effort. The StaViCTA project addressed these challenges with a focus on written text in English. The corresponding results in the area of visualization are reported in this work, based on multiple publications.

    The main goal of this dissertation is to define, categorize, and implement means for visual analysis of sentiment and stance in textual data, in particular, for social media. Our work is based on the theoretical framework and automatic classifier of stance developed by our project collaborators, involving multiple non-exclusive stance categories such as certainty and prediction. We define a design space for sentiment and stance visualization techniques based on literature surveys. We discuss multiple visualization and visual analytics approaches developed by us to facilitate the underlying research on stance analysis, data collection and annotation, and visual analysis of sentiment and stance in real-world text data from several social media sources. The work described in this dissertation was carried out in cooperation with domain experts in linguistics and computational linguistics, and our approaches were validated with case studies, expert user reviews, and critical discussion. The results of this work open up further opportunities for research in text visualization and visual text analytics. The potential application areas are academic research, business intelligence, social media monitoring, and journalism.

  • 17.
    Lindgren, Patric
    Linnaeus University, Faculty of Social Sciences, Department of Political Science.
    Småstat i brytningstid: Sveriges säkerhetspolitiska orientering efter tre världskonflikter under 1900-talet2019Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis aims to explain how small states, in this case Sweden, security politics adapts to new circumstances after great conflicts in the 20th century. The analytical model is built by a combination of the opposite theories of international politics, realism and idealism, combined with actor based and structure based perspectives and thus creating a four field analytical matrix.

    The empirical foundation constitutes of three post conflict periods; post-first world war, post-second world war and post-cold war periods. For every period three cases are analyzed; one foreign politics initiative, one association to an international organization and one defence politics decision. In the post-first world war period the focus is on the Swedish intervention of the Åland archipelago, the association to the League of Nations and disarmament decision in 1925. In the post-second world war period the focus is on the association of Sweden to the United Nations, the Swedish initiative to a Scandinavian defence alliance and the defence decision of 1948. In the post-cold war period the focus is on the Swedish association to the European Union, the Swedish participation in the NATO led IFOR operation in Bosnia and the defence decision in 1996.

    The main conclusions of these investigations are that small states, like Sweden, both are restricted in their foreign and security politics by international structures and able to use the same structure to promote their interests. Time is a key element for analyzing both structural and actor based aspects of a small states capacity. Also, in the case of Sweden, there tends to be a tension between an idealistic dominated politics and a realistic dominated politics when it comes to foreign and security politics, and that idealism seems to have increased in the latter period.

  • 18.
    Johansson, Maria C.
    Linnaeus University, Faculty of Social Sciences, Department of Education and Teacher's Practice.
    The institutionalisation of validation and the transformation of vocational knowledge: The case of admission into Vocational Teacher Education in Sweden2019Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The aim of this thesis was to understand the validation of vocational knowledge prior to entry into vocational teacher education in Sweden with regard to conceptions and understandings of vocational knowledge, and also to understand how institutional conditions, such as ideas of how to organise validation, influence the content and form of the validation practice. From this aim the following research questions were developed: What ideas about the organisation of validation stand out in the policy and practice of validation? What conceptions and understandings of vocational knowledge is the organisation of validation built on and what do they entail? Who has the agency to describe and decide upon vocational knowledge in the policy and practice of validation? What institutional arrangements appear in the practice of validation?

    To conduct the studies in the thesis a multimethods approach was adopted, combining policy analysis and interviews. For theoretical support, new institutional theories were used and also theories of knowledge. The results revealed that the regulative elements of validation have transformed vocational knowledge to fit a frame similar to formal education. In terms of norms and values, it appears as if validation is more of a social and economic project than one of accounting for vocational knowledge and vocational pride. Cultural/cognitive matters that are taken for granted when considering vocational knowledge differ quite significantly between agents involved in validation. Validation of vocational knowledge exhibits a conceptual confusion having different conceptions of knowledge simultaneously at play. This confusion blurs the boundaries between concepts of knowledge, learning, and the learning context. In the complexity of ideas of how to organise validation and different knowledge conceptions, institutional arrangements appear to be based on a sense of belonging, either to academia or to the trade. The agency of those with vocational knowledge is limited in several ways within validation.

  • 19.
    Roos, Helena
    Linnaeus University, Faculty of Technology, Department of Mathematics.
    The meaning(s) of inclusion in mathematics in student talk: Inclusion as a topic when students talk about learning and teaching in mathematics2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis contributes to research and practice within the field of special education in mathematics with more knowledge about, and an understanding of, students´ meaning(s) of inclusion in mathematics education. Three research questions guide the study: What meaning(s) is/are ascribed, and how is inclusion used, in mathematics education research? What meaning(s) do the students ascribe to inclusion in mathematics learning and teaching? And what frames students´ meaning(s) of inclusion in mathematics learning and teaching?The first part of this study began with a systematic literature review on the notion of inclusion in mathematics education research, and the search resulted in 1,296 research studies. Of these, 76 studies were retained after the criteria for time span and peer-reviewed research were applied and 19 duplicates had been removed. The second part of the study involves a case study of three students and their meaning(s) of inclusion in mathematics education. The selected school was a lower secondary school in an urban area of Sweden. The school had set out to work inclusively, meaning their aims were to include all students in the ordinary classroom teaching in every subject and to incorporate special education into the ordinary teaching with no fixed special education groups. Three students were chosen for this part of the study: one in Grade 7 and two in Grade 8. Edward, one of the students in Grade 8, was chosen because he was thought to be a student in access to mathematics education. The other two students were chosen because they were thought to be struggling to gain access to mathematics education: Veronica in Grade 7 and Ronaldo in Grade 8 (the same class as Edward). In this study, the object of the study is the meaning(s) of inclusion in student talk. This study is an instrumental and collective case (Stake, 1995), as it involves several students’ meaning(s) aimed at developing a more general understanding of inclusion in mathematics education. The case is also an information-rich case (Patton, 2002), with contributions from students in mathematics education at an inclusive school. Applying Flyvbjerg’s (2006; 2011) notions, one can also call this kind of selection “information-oriented”, and the case is an extreme one – a choice made in order to get “a best case scenario”. An extreme case is a case used to “obtain information on unusual cases  which can be especially problematic or especially good in a more closely defined sense” (Flyvbjerg, 2011, p. 307). The data in this study consists of both observations and interviews conducted during the spring semester 2016. The observations took place in a Grade 7 and Grade 8 classroom at the same school where the interviewed students were enrolled. At least one mathematics lesson each month for each class was observed, and student interviews followed each observation. The observations were used to provide a context for the interviews and to support the analysis. In this study, discourse analysis (DA) as described by Gee (2014a; 2014b) was chosen as both the theoretical frame and as an analytical tool because of its explanatory view on discourse, with description foregrounded. With the help of DA, this study describes both the meaning(s) and the use of the notion of inclusion in mathematics education research. It also describes students’ meaning(s) of inclusion in mathematics education as well as framing issues in student talk of inclusion in mathematics education. From Gee´s point of view, DA encompasses all forms of interaction, both spoken and written, and he provides a toolkit for analysing such interaction by posing questions to the text. Gee distinguishes two theoretical notions, big and small discourses, henceforth referred to as Discourse (D) and discourse (d). Discourse represents a wider context, both social and political, and is constructed upon ways of saying, doing, and being: “If you put language, action, interaction, values, beliefs, symbols, objects, tools, and places together in such a way that other recognize you as a particular type of who (identity) engaged in a particular type of what (activity), here and now, then you have pulled of a Discourse” (Gee, 2014 a, p. 52, Gee’s italics). When looking at discourse (with a small d), it focuses on language in use – the “stretches of language” we can see in the conversations we investigate (Gee, 2014a, 2014b), meaning the relations between words and sentences and how these relations visualize the themes within the conversations. These small discourses can inform on how the language is used, what typical words and themes are visible, and how the speakers or writers design the language. According to Gee (2015), big Discourse sets a larger context for the analysis of small discourse. The results of the first part of the study answer to the research question, What meaning(s) is ascribed, and how is inclusion used in mathematics education research? They show that research on inclusion in mathematics education use the term inclusion when both referring to an ideology and a way of teaching, although these two uses are usually treated separately and independently of each other. The results of the second part of the study answer to the following research questions: What meaning(s) do the students ascribe to inclusion in mathematics learning and teaching? And what frames students´ meaning(s) of inclusion in mathematics learning and teaching? These questions show how meaning(s) of inclusion in student talk can be described by three overarching Discourses: the Discourse of mathematics classroom setting, of assessment, and of accessibility in mathematics education. Within these Discourses, smaller discourses make issues of meanings of inclusion for the students visible in terms of: testing, grades, tasks, the importance of the teacher, (not) being valued, the dislike of mathematics, the classroom organization, and being in a small group. This study shows the complexities and challenges of teaching mathematics, all while simultaneously handling students’ diversity and promoting the mathematical development of each student. To enhance students’ participation and access demands that the teacher knows her or his students, is flexible, has a pedagogical stance and tactfulness, and is knowledgeable in mathematics and mathematics education. It also demands that the teacher is able to take a critical stance and resist the prevailing discourse of assessment that can sometimes overshadow the mathematics education, and in a sense, almost become mathematics for the students. Furthermore, this study also shows how complex and challenging it is to be a mathematics student: they are required to relate to, understand, and participate in many Discourses existing at the same time in a single mathematics classroom. These Discourses interrelate and are embedded in power relations between students and teachers and institutions. This demands that the students are alert and able to use various symbols and objects as well as recognize patterns, and then act accordingly. Hence, to be able to fully participate, you have to be able to talk the talk and walk the walk (Gee, 2014a). This means that not only do you have to use the language correctly, but also you have to act properly at the right time and place.

  • 20.
    Hemmilä, Venla
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Towards low-emitting and sustainable particleandfibreboards: Formaldehyde emission test methods and adhesives from biorefinery lignins2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    High volumes, fast production speed, and low material costs have been historically the driving factors of the particle- and fibreboard industries. However, in recent years the fossil-fuel dependency and health issues of the formaldehyde-containing adhesives used in the production have gained attention from both legislators and consumers. The latest example of legislation development is the change that the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety of Germany  (Bundesministerium für Umwelt, Naturschutz und Nukleare Sicherheit) made to their testing method, effectively lowering the formaldehyde emission levels of wood-based panels in Germany from the European emission level of 0.1 ppm (E1, EN 717-1) to 0.05 ppm. As the emission levels of requirements decrease, market opportunities arise for formaldehyde-free bio-based adhesive systems. The aim of this thesis was thus to evaluate the different formaldehyde test methods at low emission levels (<0.05 ppm), and to explore new adhesive alternatives to the formaldehyde and petroleum-based systems used today.

    As formaldehyde emissions decrease, choosing the right measurement method becomes increasingly important. Repeatability and correlation between the main European and American formaldehyde measurement chambers, described in EN 717-1 and ASTM D 6007 standards respectively, were determined. In addition, an alternative fast factory method based on emissions was evaluated, and the effect of reducing the conditioning time before emission measurements was investigated. A literature research was conducted on different bio-based raw materials in order to review their potential, from both scientific and industrial viewpoints, as alternatives to the current petroleum-derived and formaldehyde-based adhesives. Lignin residues from biorefinery processes were chosen for further testing due to their increasing volumes and potential to suit various pathways for adhesive making. Three different biorefinery lignins were compared, and ammonium lignosulfonate was chosen for making adhesives for particleboards by using one petroleum-based and one bio-based crosslinker.

    The main conclusion of the formaldehyde emission part of the thesis was that formaldehyde emissions can be measured both accurately and quickly at low levels using chamber methods, even at factory environment. There was a good correlation between the American D 6007 and European EN 717-1 chamber methods at emission levels <0.05 ppm for both particleboards (r2 = 0.9167) and fibreboards (r2 = 0.9443). Further understanding on the effect of edge-sealing of boards and analytical methods described in the standards was obtained. It was confirmed that a fast chamber method with 1 day conditioning and 15 minutes measuring time could be used for factory formaldehyde control for most board types.

    The bio-based adhesives’ literature review revealed a large amount of studies on different sustainable adhesive systems, some of which seem promising. Both soy protein and tannin were found to be partially commercialized, with certain pre-requisites. Kraft-lignin was especially well researched, but was found to be difficult to use for other applications than partial replacement of phenol in phenol-formaldehyde (PF) adhesives due to poor water solubility and purity. Lignin residues from biorefinery processes were found to be a less studied, growing raw-material source with a lot of potential. Thus, supercritical water hydrolysis lignin (SCWH) and two biorefinery lignosulfonates were chemically and thermally characterized, and evaluated as raw materials for value-added applications, including adhesives. SCWH lignin was found to have more β-R linkages and lower amount of impurities than the lignosulfonates. High amount of phenolic hydroxyl groups indicated that SCWH would be well suited for phenol replacement in PF adhesives. The two lignosulfonates had more aliphatic hydroxyl groups, which can be interesting for other crosslinking reactions than PF. Ammonium lignosulfonate (ALS) was chosen for further evaluation as having slightly better properties than sodium lignosulfonate (SLS). ALS was combined with one bio-based crosslinker, furfuryl alcohol (FOH), and one synthetic crosslinker, 4,4’-diphenylmethane diisocyanate (pMDI), and tested as particleboard adhesive. Although in veneer tensile shear strength testing the crosslinkers worked equally well, pMDI provided significantly better results in particleboards. In addition, higher emissions than what can be expected from wood particles alone were detected from the particleboard samples crosslinked with FOH, even though FOH can be classified as non-formaldehyde added adhesive system. Further research is needed to elucidate how much the lignin contributes to the final adhesion strength when it is used together with pMDI.

    This thesis has provided new insights on formaldehyde emissions and bio-based adhesives towards healthier and more sustainable particle- and fibreboards. It has been proven that formaldehyde emissions can be measured accurately at emission levels of wood, enabling comparisons of formaldehyde-free systems. Formaldehyde-free adhesives based on a biorefinery lignin type and pMDI showed promising results for particleboards. However, these results need to be improved by different modifications of the lignin in order to bring the adhesive system to the economical and performance level required by the particleboard industry.

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