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  • Public defence: 2017-09-01 09:00 Sal 135, byggnad 9 A, Allmänmedicin, Umeå
    Muindi, Kanyiva
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Air pollution in Nairobi slums: sources, levels and lay perceptions2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background

    Air quality in Africa has remained a relatively under-researched field. Most of the African population is dependent on biomass for cooking and heating, with most of the combustion happening in low efficiency stoves in unvented kitchens. The resulting high emissions are compounded by ingress from poor outdoor air in a context of poor emissions controls. The situation is dire in slum households where homes are crowded and space is limited, pushing households to cook in the same room that is used for sleeping. This study assessed the levels of particulate matter with aerodynamic diameter £ 2.5 microns (PM2.5) in slum households and people's perceptions of and attitudes towards air pollution and health risks of exposure in two slum areas, Viwandani and Korogocho, in the Nairobi city.

    Methods

    The study employed both qualitative and quantitative methods. For the quantitative study, we used structured questionnaires to collect data about the source of air pollution among adults aged 18 years and above and pregnant women residing in the two study communities. We used the DustTrak™ air samplers to monitor the indoor PM2.5 levels in selected households. We also collected data on community perceptions on air pollution, annoyance and associated health risks. We presented hotspot maps to portray the spatial distribution of perceptions on air pollution in the study areas. For the qualitative study, we conducted focus group discussions with adult community members. Groups were disaggregated by age to account for different languages used to communicate with the younger and older people. We analysed the qualitative data using thematic analysis.

    Results

    Household levels of PM2.5 varied widely across households and ranged from 1 to 12,369μg/m3 (SD=287.11). The household levels of PM2.5 levels were likely to exceed the WHO guidelines given the high levels observed in less than 24 hours of monitoring periods (on average 10.4 hours in Viwandani and 11.8 hours in Korogocho). Most of the respondents did not use ventilation use in the evening which coincided with the use of cookstove and lamp, mostly burning kerosene. The levels of PM2.5 varied by the type of fuels, with the highest emissions in households using kerosene for cooking and lighting. The PM2.5 levels spiked in the evenings and during periods of cooking using charcoal/wood. Despite these high levels, residents perceived indoor air to be less polluted compared with the outdoor air, possibly due to the presence of large sources of emissions near the communities such as dumpsites and industries. The community had mixed perceptions on the health impacts of air pollution, with respiratory illnesses perceived as the main consequence while vector or sanitation related diseases such as diarrhoea was also perceived to be related to air pollution.

    Conclusions

    With poor housing and reliance on dirty fuels, households in slums face potentially high levels of exposure to PM2.5 with dire implications on health. To address the poor perception on air pollution and knowledge gaps on the health effects of air pollution, education programs need to be developed and tailored. These programs should aim to provide residents with information on air quality and its impact on the health; what they can do as communities as well as empower them to reach out to government/stakeholders for action on outdoor sources of pollution such as emissions from dumpsites or industries. The government has a larger role in addressing some of the key pollution sources through policy formulation and strong implementation/enforcement.

  • Public defence: 2017-09-08 09:00 KB.E3.03 (stora hörsalen), KBC-huset, Umeå
    Lindgren, Cecilia
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Design strategies for new drugs targeting multicomponent systems: focusing on class II MHC proteins and acetylcholinesterase2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The field of medicinal chemistry is constantly evolving. Aided by advances within techniques as well as knowledge of biological systems, increasingly complex targets and drugs can be considered. This thesis includes two projects focusing on the design of drugs targeting multicomponent systems, referring to systems for which multiple components must be considered during the drug design process.

    In the first project, the long-term goal is to develop a vaccine against the autoimmune disease rheumatoid arthritis (RA). The cause of RA is unknown, but it is genetically linked to expression of class II MHC proteins that present antigens to T-cell receptors (TCRs), responsible for initiating an immune response. A glycopeptide fragment, CII259–273, from type II collagen has shown promising results as a vaccine against arthritis resembling RA in mice. CII259–273 binds to the class II MHC protein followed by presentation to the TCR, forming a multicomponent system.

    We have used molecular dynamics (MD) simulations to study the effect that modifications of CII259–273 have on the multicomponent system. Non-native amino acids and amide bond isosteres have been introduced. This has demonstrated the importance of retaining the backbone conformation of CII259–273, as well as the hydrogen bonds formed to the backbone. The ability to introduce such modifications would be of value to affect the potency towards the MHC protein, and prevent degradation of the glycopeptide. The studies have revealed a multicomponent system that is highly sensitive to even small modifications that can affect the dynamics of the entire complex.

    In the second project, the long-term goal is to develop a broad-spectrum antidote against nerve agents. Nerve agents are extremely toxic compounds that act by covalently inhibiting the enzyme acetylcholinesterase (AChE), which is essential for termination of nerve signalling. A major limitation of current antidotes is that their efficiency is dependent on the type of nerve agent. A broad-spectrum antidote must be able to bind to the multicomponent system consisting of AChE covalently inhibited by different nerve agents. It will then act by performing a nucleophilic attack on the nerve agent adduct, thus breaking the covalent bond to AChE.

    We have used statistical molecular design (SMD) and quantitative structure-activity relationship (QSAR) modelling to identify a fragment with a potency for AChE inhibited by different nerve agents. A nucleophilic component able to restore the enzyme to the active form was thereafter introduced. This resulted in a functional reactivator, efficient for multiple nerve agents. Furthermore, the mechanism of reactivation has been investigated through structural studies, enabled by a combination of X-ray crystallography and molecular modelling. A high flexibility of the reactivator, as well as the ability to bind to AChE in multiple conformations, are defined as important properties for a broad-spectrum antidote.

  • Public defence: 2017-09-08 10:00 Föreläsningssal 5, Falun
    Borg, Farhana
    Umeå University, Faculty of Social Sciences, Department of applied educational science. Högskolan Dalarna.
    Caring for people and the planet: preschool children’s knowledge and practices of sustainability2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Children across the globe today are continuously being exposed to and affected by various kinds of real-world complexities and challenges; however, research on their knowledge and practices in terms of sustainability is limited, in particular with regards to how preschool- and home-related factors are associated with their learning for sustainability. Since 1998, different types of eco-certification have been awarded by the Swedish National Agency for Education and Keep Sweden Tidy Foundation to promote education for sustainability (EfS) in all areas of education and learning. Despite certificates having been granted in Sweden since 1998, no studies have been conducted at the national level to investigate whether eco-certification has any role to play in children’s learning for environmental and sustainability issues. This knowledge is important to develop pedagogical activities to engage young children meaningfully in learning for sustainability at preschool. This study was undertaken so as to address this research gap in a Swedish context.

    The overall aim of this study was to enhance the existing knowledge about preschool children’s learning for sustainability in Sweden. The objectives of this study have been to investigate and compare the knowledge and self-reported practices of sustainability among children attending eco-certified and non-eco-certified preschools, respectively, and to explore the extent to which preschool- and home-related factors are associated with children’s knowledge and practices of sustainability. Further, this study explored children’s perceived sources of such knowledge. The term ‘knowledge’ in this text refers to the descriptions of children’s ideas and thoughts. Similarly, eco-certified preschool refers to a school that work explicitly with EfS.

    The study was designed from a "child’s perspective": this means that it was designed by adults to understand children’s perceptions and actions. Bandura’s (1977) social learning theory and Bruner’s (1961) iconic (image-based) modes of representation were applied in various stages of the study. A conceptual framework was developed within the three-interlocking-circles model of sustainability that illustrates how environmental, social and economic dimensions are interconnected. The concept of sustainability was operationalized in four themes: economic equality, resource sharing, recycling and transport use.

    With the use of illustrations and semi-structured questions, final-year preschool children (n=53), aged five to six years, and the directors (n=7) at six eco-certified and six non-eco-certified preschools were interviewed, while guardians (n=89) and teachers (n=74) filled out questionnaires. Qualitative and quantitative data were analyzed using content analysis and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA), respectively. The quality and complexity of children’s responses were assessed and classified using the SOLO Taxonomy (Biggs & Collis, 1982).

    The results showed that by the time the children completed preschool, many had acquired some knowledge about how to use money, about the sorting of different recyclable items at home and at preschool, and about the impact of different modes of transport on the environment and people’s lives. They also had ideas about the lives of other children in the world and what it can mean to share resources with other people. There was a positive relationship between children’s declarative (understanding) and functional (practice) knowledge of sustainability issues and the involvement of teachers and guardians in sustainability-related discussions and activities. No statistically significant differences between eco-certified and non-eco-certified preschools in terms of children’s declarative and functional knowledge were found. Parents were reported to be the main sources of children’s knowledge along with the children themselves, teachers and media.

    The findings offer support for integrating environmental, social and economic dimensions of sustainability into the daily pedagogical activities of preschools and for giving children opportunities to participate in discussions and practical activities that concern their lives. Further studies are needed to investigate the extent to which different educational activities contribute to developing children’s understanding and behavior when it comes to a sustainable society.

  • Public defence: 2017-09-15 10:00 Fö 5, Falun
    Persson, Anders
    Umeå University, Faculty of Arts, Department of historical, philosophical and religious studies.
    Lärartillvaro och historieundervisning: innebörder av ett nytt uppdrag i de mätbara resultatens tid2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Swedish compulsory school has recently been subjected to a number of political reforms. Between 2011 and 2014, for example, earlier grades, more national tests and a new curriculum plan (Lgr 11) were to be implemented. This thesis aims to examine those changes as they were experienced by teachers who teach history in Swedish upper primary schools. The theoretical framework is in-spired by existential philosophy, primarily as formulated in the works of Martin Heidegger and Hanna Arendt. In this way, the study highlights the teachers’ lived experience by making use of the concepts yearning, appearance, acting and mood.

    The study comprises of 36 interviews with 26 informants. The interviews were carried out and transcribed during 2014. The questions focus on both the existential being of the teachers’ lives as well as the ideological function of the history subject. This highly renders in the issue of how lived experiences of a specific school reform corresponded to the teachers’ own perception of a mean-ingful history education. Both the yearnings that were expressed by the participants and their de-scriptions of what they have experienced, have been related to the overall educational ideological functions stated by Gert Biesta (socialisation, subjectification and qualification) and Jonas Aspelin (existentialisation).

    Although the teachers’ narratives were greatly varied in some aspects, their interpretations of the new assignment seemed to be quite homogenous. Most of the teachers portrayed a situation characterised by performativity. Measurable knowledge and more frequent documentation seemed to be prioritised. Some of them stressed that they experienced less autonomy. In terms of history, the new curriculum was associated with more content knowledge, cognitive skills and procedural abilities. From the teachers’ perspective, pure qualification, rather than subjectification and social-isation, characterised the new curriculum.

    Still, the teachers’ feelings towards the curricular changes showed a great deal of divergence. Some of them embraced most of the new aspects. They claimed that clearly formulated require-ments in the history curricula provided them with security. They declared that their history teaching to some extent became more professional. In line with such beliefs, some teachers asserted that the strengthened focus on analytical skills improved their teaching. Particularly those who ex-pressed that they preferred such analytic procedural approaches described their experience in terms of confirmation and approval. Others appeared to struggle with the changes. While a few teachers even tried to resist the curricular changes, some found themselves forced to endure what appeared to be a totally new situation. They expressed disbelief, frustration and pain. Notably it was those most devoted to the existentialisational function of history teaching that usually seemed to express such alienation. As argued, they appeared to long for a lost possibility to engage their pupils, to bring history alive and to make meaning of the past.

  • Public defence: 2017-09-22 09:00 KBE303-Stora hörsalen, KBC-huset
    Zhou, Yang
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Regulation of pre-mRNA splicing and mRNA degradation in Saccharomyces cerevisiae2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Messenger RNAs are transcribed and co-transcriptionally processed in the nucleus, and transported to the cytoplasm. In the cytoplasm, mRNAs serve as the template for protein synthesis and are eventually degraded. The removal of intron sequences from a precursor mRNA is termed splicing and is carried out by the dynamic spliceosome. In this thesis, I describe the regulated splicing of two transcripts in Saccharomyces cerevisiae. I also describe a study where the mechanisms that control the expression of magnesium transporters are elucidated.

    The pre-mRNA retention and splicing (RES) complex is a spliceosome-associated protein complex that promotes the splicing and nuclear retention of a subset of pre-mRNAs. The RES complex consists of three subunits, Bud13p, Snu17p and Pml1p. We show that the lack of RES factors causes a decrease in the formation of N4-acetylcytidine (ac4C) in tRNAs. This phenotype is caused by inefficient splicing of the pre-mRNA of the TAN1 gene, which is required for the formation of ac4C in tRNAs. The RES mutants also show growth defects that are exacerbated at elevated temperatures. We show that the temperature sensitive phenotype of the bud13Δ and snu17Δ cells is caused by the inefficient splicing of the MED20 pre-mRNA. The MED20 gene encodes a subunit of the Mediator complex. Unspliced pre-mRNAs that enter the cytoplasm are usually degraded by the nonsense-mediated mRNA decay (NMD) pathway, which targets transcripts that contain premature translation termination codons. Consistent with the nuclear retention function of the RES complex, we find that NMD inactivation in the RES mutants leads to the accumulation of both TAN1 and MED20 pre-mRNAs. We also show that the cis-acting elements that promote RES-dependent splicing are different between the TAN1 and MED20 pre-mRNAs.

    The NMD pathway also targets transcripts with upstream ORFs (uORFs) for degradation. The ALR1 gene encodes the major magnesium importer in yeast, and its expression is controlled by the NMD pathway via a uORF in the 5’ untranslated region. We show that the ribosome reaches the downstream main ORF by a translation reinitiation mechanism. The NMD pathway was shown to control cellular Mg2+ levels by regulating the expression of the ALR1 gene. We further show that the NMD pathway targets the transcripts of the vacuolar Mg2+ exporter Mnr2p and the mitochondrial Mg2+ exporter Mme1p for degradation.

    In summary, we conclude that the RES complex has a role in the splicing regulation of a subset of transcripts. We also suggest a regulatory role for the NMD pathway in maintaining the cellular Mg2+ concentration by controlling the expression of Mg2+ transporters.

  • Public defence: 2017-10-10 10:30 N320, Naturvetarhuset, Umeå
    Khan, Muhammad Sikandar Lal
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Presence through actions: theories, concepts, and implementations2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    During face-to-face meetings, humans use multimodal information, including verbal information, visual information, body language, facial expressions, and other non-verbal gestures. In contrast, during computer-mediated-communication (CMC), humans rely either on mono-modal information such as text-only, voice-only, or video-only or on bi-modal information by using audiovisual modalities such as video teleconferencing. Psychologically, the difference between the two lies in the level of the subjective experience of presence, where people perceive a reduced feeling of presence in the case of CMC. Despite the current advancements in CMC, it is still far from face-to-face communication, especially in terms of the experience of presence.

    This thesis aims to introduce new concepts, theories, and technologies for presence design where the core is actions for creating presence. Thus, the contribution of the thesis can be divided into a technical contribution and a knowledge contribution. Technically, this thesis details novel technologies for improving presence experience during mediated communication (video teleconferencing). The proposed technologies include action robots (including a telepresence mechatronic robot (TEBoT) and a face robot), embodied control techniques (head orientation modeling and virtual reality headset based collaboration), and face reconstruction/retrieval algorithms. The introduced technologies enable action possibilities and embodied interactions that improve the presence experience between the distantly located participants. The novel setups were put into real experimental scenarios, and the well-known social, spatial, and gaze related problems were analyzed.

    The developed technologies and the results of the experiments led to the knowledge contribution of this thesis. In terms of knowledge contribution, this thesis presents a more general theoretical conceptual framework for mediated communication technologies. This conceptual framework can guide telepresence researchers toward the development of appropriate technologies for mediated communication applications. Furthermore, this thesis also presents a novel strong concept – presence through actions - that brings in philosophical understandings for developing presence- related technologies. The strong concept - presence through actions is an intermediate-level knowledge that proposes a new way of creating and developing future 'presence artifacts'. Presence- through actions is an action-oriented phenomenological approach to presence that differs from traditional immersive presence approaches that are based (implicitly) on rationalist, internalist views.