| 1. |
- Karlsson Tiselius, Andreas, 1977-
(författare)
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Island biogeography of young land uplift islands - viewed through the lens of bryophytes in a northern Swedish archipelago
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Increasing habitat fragmentation and rapid global warming is changing the conditions for species populations and ecological communities around the world. This presents challenges for the maintenance of biodiversity and a dominant paradigm for conservation in fragmented habitats is given by island biogeography and metapopulation (or metacommunity) ecology.In this thesis I approach key concepts (area, connectivity and community assembly) in island biogeography and metacommunity ecology within the context of a dynamic land uplift archipelago. The presented work consists of two interwoven themes: (i) A methodological theme in which statistical approaches are developed to deal with the complexities of multispecies dynamic systems, and (ii) an applied theme dealing with community assembly and island biogeography of bryophytes on young land uplift islands.To describe island connectivity for entire species assemblages, an approach using functional principal component analysis (fPCA) on patch connectivity functions (the connectivity of an island as a continuous function of a variable representing the spatial scale of species dispersal capacities) was developed. In addition, a new statistical method, functional co-inertia analysis (fCoIA), for analyzing co-variation between multivariate species data and continuous functions was developed and applied to the relation between bryophyte species incidences and the island age/area-dynamics.Primarily asexual bryophyte species are dispersal limited and presence probabilities are related to island connectivity. No such patterns were found for species, at least occasionally, producing spores. Our results suggest that bryophyte dispersal is regulated by the contribution of spores to a regional spore rain and that bryophyte species with low spore output at the landscape level may be extra vulnerable under habitat fragmentation and loss. Having specialized asexual propagules increases the presence probabilities on islands, partly compensating for the dispersal limitation in asexual species. This suggests a trade-off between dispersal and establishment capacity, but also points to the importance of local dispersal for maintaining populations under the succession driven spatial turnover of microsites on the islands. Bryophyte colonization is strongly limited by habitat availability when a given habitats is rare, but there seems to exist a threshold over which other processes (e.g. dispersal limitation) become more important. Species with more vagile life history strategies appear to be stronger affected by the area of available habitats than many perennial species
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| 2. |
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| 3. |
- Eliasson, Nina, 1965-
(författare)
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Att kommunicera skolans naturvetenskap : ett genusperspektiv på elevers deltagande i gemensam och enskild kommunikation
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Both individual and whole class communication of students are described in this thesis, which is based on a clear gender perspective. Two articles describe the participation of boys and girls in communication with the whole class, the empirical data collected consisting of videotaped lessons. The extent to which boys and girls participate in the communication is reported in the first study, and in the second the extent to which boys and girls respond to the teacher's closed or open questions about science is presented. The third study reports boys' and girls' individual communication when responding to written science questions. The summary chapter ties the results together from the perspective of Positioning Theory, making the thesis a result of Mixed Methods Research.Results show that boys participate in whole class communication more often than girls, with approximately the same level of dominance as shown in research from the early 80s. Boys also answer more questions than girls, the differences becoming apparent when teachers ask closed questions that can be answered in one or two words. In isolation, girls answer written questions to the same extent as boys, but give longer responses containing a more developed scientific language.Results showing that boys position themselves as knowledgeable more often than girls when teachers ask closed questions, are explained from the perspective of Positioning Theory. Girls more often position themselves as knowledgeable when teachers ask open questions that require reflection. In test situations, with time for reflection, the boys and girls position themselves as knowledgeable students to the same extent.Teachers need to be aware of the positioning attempts created by teaching, and consequently take into account that different approaches in teaching provide boys and girls with different access to the communication space.
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| 4. |
- Florén, Thomas, 1969-
(författare)
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Talangfabriken : Om organisation av kunskap och kreativitet i skivindustrin
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The purpose of this dissertation is to describe, explain and understand how record companies identify and develop new music and new talent. The analysis is carried out on three levels: individual, organizational and sector level. In a record company, this task formally goes to A&R (Artist and Repertoire). This dissertation takes its point of departure in how the capacity for discovering new talent can be understood in terms of knowledge, creativity and competence and how this capacity is affected in the meeting between the record company and the industry.The theoretical framework of the dissertation spans two sociological fields: the sociology of organizations and the sociology of knowledge. While it takes its organizational starting point in the Knowledge Company Approach, it employs a practice-based approach to discuss knowledge. I argue that within the Knowledge company approach there are two contrasting ways to understand knowledge; a distinction is made between knowledge- and creativity-intensive enterprises. The results show that the record industry’s polarized structure can be seen as a result of the Knowledge Company’s typical problems.The A&R’s work is described as including two phases, one intuitive and one analytical. The intuitive assessment is direct, unconscious and without reflection. This ability has been described as "intuition" and "gut feeling". The analytical phase adds analysis and reflection based on knowledge. The results from the interviews with A&R’s reveal the limit of formal and explicit knowledge not only in the choice of music but also in the marketing strategies.The overarching picture is one in which record companies move in a space characterized by tension between dichotomous forces – art and commercialism, creativity and knowledge, culture and economy, chaos and order, but where opposite poles are not mutually exclusive but complementary.
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| 5. |
- Grabowski, Pawel, 1975-
(författare)
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Telomere length as prognostic parameter in chronic lymphocytic leukemia
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- B-cell chronic lymphocytic leukemia (B-CLL) is the most common leukemia among the adult population in western countries and accounts for 30-40% of all leukemias. With survival time ranging from months to decades, the clinical course of individual CLL patients is highly variable. This heterogeneity and in the end the need for means to identify the patients with less favorable disease has encouraged the search for biomarkers that can predict the prognosis. Telomeres are repetitive structures protecting the chromosomal endings and shorten at each cell division. Telomere length (TL) has been indicated as a prognostic factor both in hematological malignancies and solid tumors. In B-CLL, TL is associated with mutation status of the immunoglobulin heavy chain variable (IGHV) gene and with clinical course. In the present thesis the main aim was to evaluate TL as a biomarker in B-CLL using a quantitative PCR-based method for TL determination. In paper I, TL was shown to be a prognostic factor for stage A and stage B/C patients, whereas IGHV mutation status predicted outcome only in stage A patients. Moreover, IGHV mutated CLL cases were subdivided by TL into two groups with different prognosis, a subdivision not seen for unmutated cases. Interestingly, the IGHV-mutated group with short telomeres had en overall survival close to that of the unmutated cases. Thus, a combination of IGHV mutation status and telomere length gave an improved subclassification of CLL identifying previously unrecognized patient groups with different outcomes. TL correlates with cellular origin of B-cell malignancies in relation to the germinal center (GC). In paper II different B-cell lymphoma/leukemia subtypes were analyzed. Shortest telomeres were found in IGHV unmutated CLLs, differing significantly from IGHV mutated cases. Contrary to this, mantle cell lymphomas (MCL) demonstrated similar TL regardless of IGHV mutation status. TL differed significantly between GC-like and non-GC-like diffuse large B-cell lymphomas (DLBCL) and follicular lymphomas (FL) had shorter telomeres than GC-like DLBCL. Hairy cell leukemias, which display Ig gene intraclonal heterogeneity, had longer telomeres than FLs and non-GC-DLBCL, but shorter than GC-DLBCL. In conclusion, TL seemed not to simply correlate with GC origin. Paper III presents a B-CLL cohort assessed for TL, genomic aberrations, IGHV mutation status, CD38 and ZAP-70 expression. An inverse correlation existed between TL and IGHV homology, CD38 and ZAP-70 expression. The presence of genomic aberrations was similar among patients regardless of TL. In contrast, 13q deletion, a favorable biomarker, was more frequent in patients with long telomeres, while 11q and 17p deletions (markers of less favorable outcome) were more frequent in the subgroup with short telomeres. In paper IV a large group of mainly indolent CLL cases from a population based cohort was studied again showing an association between TL and prognosis, especially in “good” prognosis cases as defined by other biomarkers. Multivariate analysis indicated a strong connection between IGHV mutation status, lipoprotein lipase (LPL) expression and TL. A comparison of TL in diagnostic and follow up samples demonstrated a significant correlation, and also in the follow samples TL constituted a significant biomarker for survival.
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| 6. |
- Gustafson, Åsa, 1968-
(författare)
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Sköra livsmönster : Om integrations- och normaliseringsprocesser bland bosniska flyktingar
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this study is to illustrate and unfold the dynamic interaction between conditions of integration and patterns of integration, in other words the structural conditions related to processes of integration and normalization of every day life. This is done with concrete reference to Bosnian refugees living in Malmö and Umeå during 1996-1997, having received permanent permission to stay in Sweden during 1992-1995. How do refugees under different conditions arrange their lives, perceive their own life situation, manage the course of daily life and develop individual life patterns? The study shows that processes of integration and normalisation depend on and has an impact on involvement and participation in social, economic, political and cultural life in general. Background statistics, official documents and local daily press material together with intense interviews with Bosnian refugees and key-informants constitute the empirical base of the study. The theoretical base consists of a holistic perspective on integration, including aspects of ethnicity, culture and gender. The focus is on the double-sided processes of integration among refugees in relation to the established population. Refugees’ processes of integration and normalization are described and discussed with reference to patterns of living conditions, patterns of integration, patterns of action and patterns of attitudes. The general conclusion is that refugees’ life patterns are very fragile. Processes of integration and normalization depend on conditions of involvement and of participation as well as the openness of the society at large and specifically on how civil, political and social rights are supplied for. This in turn raises the question of the importance of not only formal but also substantial citizenship rights. Integration is also closely related to possible changes towards more flexible gendered spaces of action. The more equal gender relations in the family become the more it opens up for possibilities of integration and normalization for both women and men. Encompassing possibilities to integration into the society at large combined with increased potentials of altering conventional power relations between women and men are vital for the processes of integration and normalization among refugees.
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| 7. |
- Heuman, Anna, 1990-
(författare)
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Negotiating standard language ideology : Metalinguistic discussions in mundane, online interaction
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis investigates how ordinary language users enact language policy and thus negotiate (standard) language ideology in mundane, online interaction. The language policy work is found in metalinguistic discussions on various social media. The discussions have been triggered by deviations from standard written language, mostly on the level of orthography. The discussions mainly target different aspects of standard language ideology. The three studies included in this compilation thesis identify discursive strategies and reveal the contradictory ideologies underpinning the discussions.The discussions are analysed with an interactional and procedural focus, highlighting the unfolding negotiations of standard language ideology. The results show that standard language ideology is prevailing which, in turn, enables certain realisations. When drawing on standard norms, the participants can use strategies that do not include explicit arguments. However, the discussions also include contradictions and strategies that challenge traditional standard beliefs. These results illustrate the mundane, vivid metalinguistic negotiations in which standard language ideology is primarily enforced, but also challenged.The results illuminate how standardisation is not a mythical and imperceptible process, but one of constant and visible iteration, also in very mundane situations. Furthermore, the pervasiveness of standard language ideology could make it harder for those who deviate from it to be listened to or even to participate at all. In this way, everyday metalinguistic discussions are one among many language policy activities that can enforce loyalty to the standard variety and its position as unmarked.
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| 8. |
- Johansson, Fredrik
(författare)
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Evaluating the performance of TEWA systems
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- It is in military engagements the task of the air defense to protect valuable assets such as air bases from being destroyed by hostile aircrafts and missiles. In order to fulfill this mission, the defenders are equipped with sensors and firing units. To infer whether a target is hostile and threatening or not is far from a trivial task. This is dealt with in a threat evaluation process, in which the targets are ranked based upon their estimated level of threat posed to the defended assets. Once the degree of threat has been estimated, the problem of weapon allocation comes into the picture. Given that a number of threatening targets have been identified, the defenders need to decide on whether any firing units shall be allocated to the targets, and if so, which firing unit to engage which target. To complicate matters, the outcomes of such engagements are usually stochastic. Moreover, there are often tight time constraints on how fast the threat evaluation and weapon allocation processes need to be executed. There are already today a large number of threat evaluation and weapon allocation (TEWA) systems in use, i.e. decision support systems aiding military decision makers with the threat evaluation and weapon allocation processes. However, despite the critical role of such systems, it is not clear how to evaluate the performance of the systems and their algorithms. Hence, the work in thesis is focused on the development and evaluation of TEWA systems, and the algorithms for threat evaluation and weapon allocation being part of such systems. A number of algorithms for threat evaluation and static weapon allocation are suggested and implemented, and testbeds for facilitating the evaluation of these are developed. Experimental results show that the use of particle swarm optimization is suitable for real-time target-based weapon allocation in situations involving up to approximately ten targets and ten firing units, while it for larger problem sizes gives better results to make use of an enhanced greedy maximum marginal return algorithm, or a genetic algorithm seeded with the solution returned by the greedy algorithm.
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| 9. |
- Karlsson, Maria, 1975-
(författare)
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Estimators of semiparametric truncated and censored regression models
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis contributes in several ways to the existing knowledge on estimation of truncated, censored, and left truncated right censored (LTRC) regression models. Three new semiparametric estimators are proposed, allowing for asymmetric error distributions. A bootstrap method for estimation of the covariance matrix of the quadratic mode estimator (QME) is proposed and studied. In addition, finite sample properties of estimators for truncated, censored, and LTRC data are studied within simulation studies and applications with real data. The first paper consists of a simulation study of the QME and other estimators of truncated regression models. The paper contributes with results suggesting the bootstrap technique being potentially useful for estimation of the QME covariance matrix. In the second paper estimators of truncated and censored semiparametric regression models are proposed. These estimators are generalizations of the QME and the winsorized mean estimator (WME) by allowing asymmetric ``trimming'' of observations. Consistency and asymptotic normality of the estimators are shown. By combining the two moment restrictions used to derive the estimators in the second paper, a consistent estimator of LTRC regression models is proposed in the third paper. The fourth paper contains an application where LTRC interpurchase intervals of cars are analysed. Results regarding the interpurchase behaviour of consumers are provided, as are results on estimator properties.
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| 10. |
- Persson Borres, Magnus
(författare)
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Metachromatic cells and eosinophils in atopic children : A prospective study
- 1991
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Metachromatic cells and eosinophil leukocytes were studied prospectively in 64 newborns with and without a family history of atopic disease (FH). Cellfindings in nasal mucosa and peripheral blood were related to development of atopic symptoms up to 18 months of age. For this purpose, a gentle scraping method suitable for infants was developed. Nasal metachromatic cells were more prevalent in atopic than in non-atopic infants. The cells were found in infants with respiratory allergy as well as in infants with eczema. Non-atopic infants with metachromatic cells all had FH. The cells were detected prior to or at the time of diagnosis. Thus, metachromatic cells are associated with atopic propensity as defined by development of atopic disease and/or a FH. Infants with respiratory allergy had more often acute otitis media compared to infants with eczema and non-atopic infants. Appearance of nasal metachromatic cells were associated with increased middle ear morbidity in atopic and non-atopic infants and high scores of cells correlated with high numbers of otitis media. Infants with respiratoryallergy may have otitis media as a result of the allergic condition. Blood eosinophils were studied in a total of 154 infants and were found to decrease with age. Blood eosinophilia at 3 months preceded atopic development but was not associated with FH. Nasal eosinophilia was a common finding in atopic and non-atopic infants. In conclusion, appearance of nasal metachromatic cells and blood eosinophilia are associated with atopic disease and may have roles as predictors of atopic disease.
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