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Sökning: mat:dok lärosäte:mah år:(2015)

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1.
  • Albèr, Cathrine (författare)
  • Humectants and skin : effects of hydration from molecule to man
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Humectants belong to a group of hydrophilic compounds frequently used in skin care products with the aim to diminish the clinical symptom of skin dryness. The biochemical and biophysical mechanisms by which humectants interact with the skin barrier are far from fully understood. Increased understanding of such mechanisms can enhance the possibilities to tailor skin care products for various skin abnormalities. The work presented in this thesis centres on one high (hyaluronan) and two low (urea and glycerol) molecular weight humectants and their interactions with water, as well as their effect on the barrier properties of the outermost layer of the skin, i.e. the stratum corneum (SC). We explore the effect of hydration on thermodynamic properties of humectants, in particular hyaluronan, by using isothermal sorption calorimetry, differential scanning calorimetry and small- and wide-angle X-ray scattering. By combining data from several methods, a binary phase diagram of the hyaluronan - water system was constructed. We also investigate the effect of hydration and presence of humectants on the SC permeability in vitro by using an experimental set-up that allows for control of the boundary conditions in terms of water activity. In contrast to low molecular weight humectants, like urea and glycerol, it was concluded that hyaluronan (17 kDa) does not penetrate the skin barrier due to size exclusion. Addition of urea, glycerol or hyaluronan to aqueous formulations inevitably lowers the water activity of the formulation, which in tum affects the SC permeability when being applied. Moreover, it was shown that skin permeability of a model drug metronidazole decreases upon addition of hyaluronan to the formulation, while high skin permeability was maintained with addition of urea or glycerol. In addition, skin membrane electrical resistance, which normally increases at dehydrating skin conditions, remained low in presence of urea and glycerol. Excised skin hydrated at different hydration levels were examined with confocal Raman microspectroscopy. Large water inclusions were observed in fully hydrated SC after 24h exposure to a buffer solution. Addition of urea was shown to promote the formation of these inclusions. Urea and glycerol were also shown to improve the hydration capacity of isolated comeocytes. Similar approach as used in vitro was employed in vivo to explore the effect of hydration and humectants on skin permeability. It was shown that the water activity of the applied formulations have a marked effect on the barrier properties and urea and glycerol was shown to improve skin hydration even at reduced water activity of the applied formulation.
2.
  • Cecchinato, Francesca (författare)
  • On magnesium-modified titanium coatings and magnesium alloys for oral orthopaedic applications: in vitro investigation
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • In dentistry and orthopaedic surgery, research to find and develop improved biomaterials is progressing rapidly. Of specific interest is to accelerate bone formation around the implant surface, which could improve the reliability of the implant even in patients with compromised situations. Although the surface modification of the implant has been proven to certain extent to promote osseointegration, the lack of bone in the patient remains a major issue and bone augmentation is commonly conducted prior to implant insertion. Synthetic and naturally derived resorbable materials are commonly used. However, problems such as the lack of optimal mechanical properties or the undesirable material resorption kinetics still exist and there still remain possibility for improvement. Clinical approaches for orthopaedic trauma require the use of non-resorbable screws, plates and pins made of metallic materials such as titanium, cobalt-chrome and stainless steel alloys. The major drawback of these materials is the need of implant removal at re-entry. Therefore, the research of bioresorbable materials that could withstand the mechanical stresses is an ongoing topic.Based on this clinical reality, the aim of this thesis was to investigate the suitability of magnesium (Mg) as a biomaterial for regenerative bone applications. Namely, Mg as a doping material for engineered mesoporous titanium implant surfaces (Studies I, II and III), and as a bioresorbable metal alloy for bone regeneration in bone trauma and bone defects conditions (Study IV).Study I, II, III Mesoporous titania films produced with evaporation-induced selfassembly (EISA) technique and applied as implant surface coatings are under investigation as a release system for the controlled administration of several substances, such as osteoporotic drugs, to enhance early bone anchorage to the implant. Modulating the pore size of such films though the selection of EISA parameters permits to control the adsorption of such substances into the mesoporous matrix and their subsequent release into the peri-implant region. Studies I, II and III analysed the effect of Mg incorporation into mesoporous titania coatings towards two cellular models during early and later stages of cell activity.Study I characterized the morphology, chemistry, and topography of mesoporous titania coatings and the effects of Mg-loading on surface micro- and nano-structures. Mg release was determined and its effect was evaluated on human foetal osteoblast populations. It was shown that mesoporous films possessed a smooth surface with pores that faced outward. Mg adsorption did not substantially alter the mesoporous surface roughness both at micro- and nano- levels. Mg was released within 24 hours of incubation in cell culture conditions, thus its bioactive effect only occurred during initial osteoblasts activity. Study II evaluated the ability of Mg-loaded mesoporous coatings to modulate multipotent adipose-derived stromal cell differentiation toward the osteoblast phenotype. The results demonstrated that Mg release had a strong impact on this cellular model, promoting osteoblast marker expression in standard cell culture conditions. Interestingly, Mg significantly promoted the expression of osteopontin, a protein that is essential for early biomaterial-cell osteogenic interaction.In study III, the reagents and EISA parameters in the mesoporous deposition were varied to generate three mesoporous titania coatings with 2-, 6- and 7-nm average pore size, to increase Mg content in the interconnected porosity of the films. The effect of various Mg contents released from the three mesoporous structureswas tested on human foetal osteoblasts populations with pre-designed osteogenic PCR arrays and real-time polymerase chain reaction. It was shown that Mg release affected osteogenesis and was controlled by tuning the pore dimensions of the mesoporous films. Increasing pore size by 1 nm (from 6 nm to 7 nm) significantly enhanced the bioactivity of the film without altering the surface roughness.Study IV In orthopaedics Mg alloys has received increasing attention as bioresorbable metals for bone regeneration. However, localized material degradation is too fast and provokes the premature loss of mechanical properties, preventing correct cellular development and bone healing in vivo . For this reason, various alloying elements are combined with high-purity Mg to modulate and optimize degradation behaviour. Study IV of this thesis investigated the degradation parameters of Mg2Ag, Mg10Gd, and Mg4Y3RE alloys and how the alloys differently affect human umbilical cord perivascular cell adhesion and spreading. Mg4Y3RE showed the highest degradation rate and, thereby, the highest trend in increases in pH and osmolality of the surrounding fluid. However, both Mg4Y3RE and Mg10Gd allowed cells to better adhere and spread across their degraded surfaces; in comparison, surface degradation of Mg2Ag was more aggressive with weak or no visible cellular structures on it. Conclusions In summary, the results of the present thesis explored the potential of Mg for its application in bone tissue regeneration. Titanium implant surfaces coated with mesoporous TiO2 thin films and further loaded with Mg enhanced bone cell activity and osteoprogenitor development into mature osteoblasts. Thus, mesoporous deposition followed by Mg loading may be a suitable alternative to existing implant surface treatments. Bioresorbable materials must degrade slowly and uniformly in order to simulate the tissue healing process. Mg10Gd possesses reduced content of alloying element and a suitable homogenous degradation pattern in vitro that allows proper adhesion of undifferentiated cells. Mg10Gd thus represents a biodegradable Mg-based material with promising mechanical and biological properties for use in dental and orthopaedic fields.
3.
  • Dimberg, Lillemor (författare)
  • Malocclusions and quality of life : cross-sectional and longitudinal studies in children
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • There are few longitudinal studies of the prevalence of malocclusions and possible self-correction of malocclusions during the development of the dentition. Early intervention might be unnecessary if self- correction of the malocclusion occurs during the transition from the primary to the permanent dentition. Most studies are cross-sectional and in those of longitudinal design, the results are inconsistent and difficult to interpret. Malocclusions may or may not influence the quality of life in children and adolescents. Thus, evaluations of the influence of different malocclusions on quality of life will certainly underpin a broader understanding and knowledge about how malocclusions affect the daily life of young patients. This information may also be important when it comes to assessing the most appropriate time for starting orthodontic treatment, not only from a professional point of view, but also, most importantly, from the patients’ perspective. The overall aim of this thesis was therefore to evaluate the prevalence of malocclusions, and to document changes occurring during the development of the dentition, from the primary dentition stage at age 3, through the mixed dentition at age 7, to the early permanent dentition at age 11.5 years. Further aims were to review the current state of knowledge about the impact of malocclusions on oral health related quality of life (OHRQoL) and to investigate how malocclusions affect the quality of life in a cohort of children, aged 11.5 years, whose dental care is provided by the Swedish Public Dental Service.
4.
  • Emilson, Anders (författare)
  • Design in the space between stories : design for social innovation and sustainability–from responding to societal challenges to preparing for societal collapse
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • We seem to be approaching the end of the era we know as Industrial Civilization. If this is the case, we will leave a stable period of progress and growth and enter into a long period of decline where many of our systems and support structures will collapse. From the perspective of how we are accustomed to living our lives and the narratives we live by, the future looks dark. How will this affect an optimistic, creative, and future-making discipline like design, a discipline which emerged out of the industrial revolution? What can design offer in the transition from industrial civilization to a new society where we can survive and thrive? What is the task of design if not to design for the market economy? What possible futures will designers then propose? Designers will need to learn to navigate future paths: those that will likely lead to sustainability and those that will likely lead to collapse. In this thesis, I explore the two paths, or scenario storylines, of Great Transition and Conventional Development. I consider the space between these stories—the space between sustainability and collapse—as a design space with many possible futures to explore. I propose that designers not only address societal challenges with the belief that we can solve them and live in a world that is both sustainable and resilient, but also consider what it means to fail and address the prospect of societal collapse. What kind of world will we end up in then? And what can we do to avoid a collapse or else prepare ourselves for a life in a world of societal breakdown? In the search for the answers to these questions, I explore design things and how values and frames as well as stories and design fictions can be used by constellations of concerned citizens when exploring possible futures.
5.
  • Glaser, Joakim (författare)
  • Från Mielke till Merkel. Kontinuitet, brott och förändring i supporterkultur i östra Tyskland
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Det övergripande syftet med avhandlingen är att undersöka det dialektiska förhållandet mellan å ena sidan identitetsskapande processer kring fotbollsklubbar och å andra sidan samhällsförändringar. Ytterst handlar det sålunda om hur fotbollssupportrars identitetsformeringar påverkats av och påverkat historiska, politiska och sociala förändringar i östra Tyskland mellan 1965 och 2015. Avhandlingen bygger på två fundament. Det första är den historiska och sociala kontext som supporterkulturen är en del av. Det handlar om DDR och den så kallade återföreningen av Tyskland och dess historiska och sociala konsekvenser, och, vilket är nog så viktig, min egen förförståelse för och kunskap om dessa företeelser. Det andra fundamentet, vilket kanske är det viktigaste, är de intervjuade östtyska fotbollssupportrarna och deras narrativ om fotbollens roll i detta sammanhang. Avhandlingen är baserad på intervjuer och deltagande observationer genomförda med supportrar till BFC Dynamo, FC Erzgebirge Aue, 1. FC Magdeburg och 1. FC Union Berlin. I avhandlingen utgår jag från tre narrativa nivåer. För det första en narrativ nivå som utgår från de intervjuades personliga erfarenheter och berättelser. För det andra en narrativ nivå som framför allt kopplas till klubbarna, men också till region eller stad och andra fenomen som förknippas med klubben, och därigenom skapar en gemensam identifikation. Slutligen en tredje narrativ nivå som utgår från det hegemoniska, och där dominerande diskurser, makt, ekonomiska och sociala strukturer och förhållanden mellan östra och västra Tyskland är viktiga. Det är framför allt på denna tredje nivå som begreppet diskurs används och knyts till det hegemoniska. Genom att studera hur dessa tre nivåer förhåller sig till varandra i de olika berättelserna synliggörs växelverkan mellan identitetsskapande och olika narrativ. Studien visar att supporterkulturen i DDR kännetecknades av en viss frihet som till en början både uppmuntrades och accepterades av statsmakten i DDR. Med tiden kom emellertid supporterkulturen att uppfattas som ett tilltagande problem. Det är en förklaring till att fotbollen och supporterkulturen i DDR av vissa forskare har tolkats som fora för politiska protester vilka banade väg för DDR:s kollaps och den tyska återföreningen. De intervjuade supportrarnas narrativ bekräftar också att åskådare vid tillfällen artikulerade ett missnöje med situationen i DDR, men att fotbollen och supporterkulturen inte spelade samma politiska roll som den evangeliska kyrkan eller Neues Forum. I avhandlingen visar jag vidare att de intervjuades narrativ ger vid handen att fotbollen och supporterkulturen förlorade i betydelse under die Wende. Nya strukturer och hegemoniska diskurser utmanade etablerade sociala och kulturella praktiker i östra Tyskland. Sammanslagningen av de två tyska fotbollsförbunden resulterade i en underordnad position för de före detta DDR-klubbarna och deras supportrar. En konsekvens av detta var att nation och makt kom att bli viktiga inslag i identitetsskapandet kring fotbollsklubbarna och supporterkulturen efter den tyska återföreningen. Jag åskådliggör i avhandlingen också hur identifikationen med östra Tyskland till viss del har vuxit sig starkare än vad som var fallet under DDR-tiden. Det ojämlika maktförhållandet inom fotbollen mellan östra och västra Tyskland och reaktioner på västtyska fördomar om östtyska fotbollssupportrar är några exempel på situationer som har konstruerat östtyska identiteter efter 1990. Även om supportrarnas narrativ ger uttryck för olika situerade östtyska identiteter är attityderna till den tyska återföreningen överlag positiva. Supporterkulturen i östra Tyskland är ett ovanligt kulturellt fenomen som konstruerar sammanhängande narrativ, vilka binder samman DDR med Förbundsrepubliken. Genom att studera hur dessa narrativ konstrueras har jag undvikit att tolka DDR som en anomali i den tyska historien. På detta sätt bidrar avhandlingen med ny kunskap om och ny förståelse både för supporterkulturen i östra Tyskland och för den tyska återföreningen.
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6.
  • Halldin, Anders (författare)
  • On a biomechanical approach to analysis of stability and load bearing capacity of oral implants
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Introduction When an implant is placed in the bone the body responds to the trauma by encapsulating the implant and its survival depends on the ability for hard tissue encapsulation. The stability of the implant during the healing phase is essential to achieve a good result [1]. Biological, physiological and mechanical phenomena affect implant stability. To achieve sufficient stability during the initial healing phase the implant has to provide sufficient static interaction with the bone. The static interaction might affect the biological processes that in turn affect implant stability. Although, numerous studies on the effect of dynamic interaction on implant stability and bone remodeling exist, the effect of static strain has yet to be clarified. As the healing progresses it may result in bone formation in close contact with the implant (i.e osseointegration) that stabilizes the implant. It has been found that implant surface modifications at the micro level promote osseointegration and that moderately roughened implants provide rapid and strong bone response [2, 3]. In addition, the application of nanostructures to an implant surface has been shown to elicit an initial complex gene response that may result in further enhancement in bone formation around the implant [4]. Furthermore the implant surface structure interlocks mechanically with the bone that affects the stability of the implant.The implant surface design has to take into account both biological and mechanical behavior of the tissues. Materials and methods To investigate how implant stability and the biological response are affected by an induced static load to the bone an in vivo study was performed. Two types of controlled static loads, excessive and moderate, were induced by specially designed implants. Two types of surface structure, turned and blasted, were applied on the implants. The implants were inserted in rabbits and healed for 3-84 days before the stability was measured by removal torque. To simulate how the pressure changes, due to biological and mechanical phenomena, on an implant surface that was subjected to an initial pressure, a constitutive model was developed that was comprised of visco-elastic, visco-plastic and remodeling components. The pressure on the surface in turn affects the implant stability. To investigate how the biomechanical and the biological responses are affected by the surface structure an in vivo study and a finite element analysis of the theoretical interfacial shear strength were performed. In the pre-clinical study, three groups of implants with different nano- and microstructures were compared to an implant with a control surface structure. The theoretical interfacial strength at different healing times was estimated by simulating the surface structure interlocking capacity to bone using an explicit finite element method. Simulations were performed for different surface structures and for different pressures, simulating visco-elastic and remodeling phenomena.Results Implants that induced a moderate bone condensation in the bone had a significantly higher removal torque value at the implantation times of 3-24 days compared to implants that did not induce condensation. The effect the induced moderate bone condensation had on implant stability decreases over time until the pressure has vanished, which approximately occurred after 28-30 days. Turned implants, placed in tibia, that induced excessive bone condensation resulted in significant increased implant stability at implantation times of 3-24 days compared to implants that induced no condensation. However, when they were placed in femur it provided no significant difference in removal torque at an implantation time of 24 days compared to implants that induced no condensation. The developed constitutive model is able to capture visco-elastic material behavior and remodeling phenomena of cortical bone which can be used to simulate how the pressure changes on an implant surface that is subjected to an initial pressure caused by condensation. The implant nano- and microsurface structure affects the magnitude of the removal torque value. It was found that implants, with no significant difference in surface roughness parameters (Sa, Ssk, Sdr) on micro level, can present a significant difference in removal torque value at 4 weeks of implantation time. In addition, it was also found that implants with a significant difference in surface roughness parameters (Sa, Ssk, Sdr) can present no significant difference in removal torque value at 4 weeks of implantation times. The difference may be due to various biological responses from the nano- and microstructure surfaces. The simulated interfacial strength for the different surfaces did not reach the interfacial strength that corresponds to the removal torque obtained in the in vivo study. Comparing the two surfaces in respect of removal torque ratio, suggests that during the early healing phase the difference is caused by different bone formation rates from biological processes. As the healing progresses the effect of structural interlocking capacity is more pronounced. Conclusions The results suggest that increased static strain in the bone not only creates higher implant stability at the time of insertion, but also generates increased implant stability throughout the observation period of 3-24 days. The proposed constitutive material model consists of three different components: a visco-elastic component, a visco-plastic component and a remodeling component. The model captures with good agreement the experimental behavior of cortical bone during different longitudinal loading situations i.e. in vitro stress-strain relationship, in vivo relaxation, in vitro creep and in vivo remodeling. The results of the present study suggest that nano- and microstructure alteration on a blasted implant might enhance the initial biomechanical performance, while for longer healing times, the surface interlocking capacity seems to be more important. Simulation of the interfacial shear strength by means of finite element analysis seems to be a promising method to estimate the load bearing capacity of the bone-to-implant interface for different surface structures at stable healing conditions i.e. longer healing times. Furthermore, it is a promising method to estimate the implant stability for different magnitudes of condensation.
7.
  • Harvard Maare, Åsa (författare)
  • Designing for Peer Learning : : Mathematics, Games and Peer Groups in Leisure-time Centers
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Constrained by national tests and the mathematics curriculum, teachers have problems finding time for exploratory and hands-on mathematical activities, especially so in classes with a reduced pace of progression, for example because of a large proportion of second-language learners. Could the leisure-time center, where time is not earmarked, provide such opportunities? The conclusion of this thesis is that this can be done, on the condition that designed activities build on the central premise of the leisure-time center: children have the right to choose which activities to engage with. The thesis is interdisciplinary, combining design research, situated cognition/embodied interaction, and pedagogy. The empirical material comes from a design project conducted in collaboration with the Rook, a multicultural school with an integrated leisure-time center. The participating children were 7-9 years old. The games studied were card and board games, especially combinatorial mathematics games (Set and Nim). The situated and embodied approach towards design is reflected in the analysis, which approaches visual artifacts as parts of multimodal communicative scenes with many co-present participants engaged in playing games or solving problems. It is shown that children learn the game through observation and participation, either as players or in non-playing roles. For many games, rules are written in a format that is inaccessible to children. One of the design tasks in the project has been to develop secondary artifacts related to games: graphic guides, conceptual maps, and paper-based exercises that can be used by children without adult support. The premise of the learners’ right to choose has many consequences for the design of learning activities. One is that motivation changes from being a property of the learner to a property of the activity. In order to highlight this difference, this thesis proposes the notions of learnability and learnworthiness to describe those aspects of an activity and its context which make it motivating from the learner’s perspective. The thesis concludes with a discussion of how design can increase the learnability and learnworthiness of a learning activity. Watching the activity being practiced is the most important resource for potential participants to determine its learnability and learnworthiness. The qualities determining the learnworthiness of an activity are reciprocity, mastery, and the potential for closure. Watching a peer successfully solving a task increases the learnability for the observers as well. If problem-solvers think aloud and use their hands to move or point at cards, collaboration and learning by observers is facilitated. Providing games with non-competitive side activities creates opportunities for deliberate practice, and offers a safe entry for children who are reluctant to engage as players.
8.
  • Hasslöf, Helen, 1961- (författare)
  • The educational challenge in "education for sustainable development" : : qualification, social change and the political
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • This thesis explores how Education for Sustainable Development (ESD) as an overarching perspective makes meaning of educational aims and purposes. Sustainable development, as a concept, is by necessity complex, and deals with integrated dimensions of environmental, social-cultural and economic sustainability. It involves a diverse range of embedded values and ideologies and calls for engagement in value-related and political issues relating to environment, equality and lifestyle. In my thesis, I have turned to the actors in social practice who are set to realise the educational perspectives of ESD – the teachers. Accordingly, the analyses departure from secondary and upper secondary school teachers’ reciprocal meaning-making when discussing the desirable aims of teaching and ESD. Building upon previous educational research, the thesis has three purposes, and the results are presented in four articles. The results of the studies bring new empirical knowledge and perspectives to educational research and practice, by adding further understanding of the political and democratic dimensions of ESD. The first purpose is to investigate and describe the complexity of the concept of sustainable development from a conflict perspective and to analyse meaning-making discussions of sustainability in an educational context. This is elaborated in the first study (Article I). To achieve this, a Conflict Reflection Tool (CRT) has been developed, by combining the conflicting dynamics of sustainable development with dialogic and univocal functions of speech. In the included case study, the CRT analysis of teachers’ discussions shows how fact-based, univocal science utterances closed the discussion for conflicting perspectives to emerge. However, conflicting views did emerge and were re-valued in a dialogic genre through the interplay of different dimensions of sustainability and different societal levels of conflicts. The second purpose is to investigate how the desired aims of ESD are (re)articulated in areas of educational tension in order to make particular meaning by teachers with experience in ESD practice. Three complex ESD areas are in focus, namely, the development of students as political subjects (Article II), qualification in relation to ESD (Article III), and education for social change in relation to ‘sustainable’ living (Article IV). In each of these areas, the functions of qualification, socialisation and subjectification (c.f. Biesta) are relationally analysed to further problematise educational purposes. Through analyses with inpiration from discourse theory, the results show in Article II the emerging discourse of critical thinking as room for subjectification where students were invited to be adressed as political subjects. This discourse was articulated in struggle with the aims of qualification and socialisation, i.e. challenged by elements articulating a more scientific and rational worldview. Article III shows three discourses of qualification. Of these three, scientific reasoning and awareness of complexity are articulated as contrasting epistemological discourses of qualification. However, in the third discourse, qualification as critical thinking, these different epistemological views are articulated as intertwined as different ways to view sustainability. Article IV shows how the teachers struggle between three positions: the rational subject, as a neutral conductor; the responsible subject, as a role model, or the reconstructing subject, as a reconstructor. The overlapping positions depend upon how socialisation towards sustainable lifestyles, political and ethical perspectives are identified in relation to the educational aims and the emerging myths of social change. The third purpose is to develop analytical methods where conflicting articulations of environmental issues and sustainability are taken into account based on language and discourse theory for conducting empirical investigations of meaning-making.
9.
  • Kisch, Annika M (författare)
  • Allogeneic stem cell transplantation : patients’ and sibling donors’ perspectives
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Allogeneic haematopoietic stem cell transplantation (hereafter HSCT) is an established treatment which offers a potential cure for a variety of diseases, mainly haematological malignancies. However, the treatment is also associated with significant risks of acute complications and late side effects, including mortality. The donor is either a relative, most often a sibling, or an unrelated registry donor. Methods for donating stem cells are bone marrow harvesting or peripheral blood stem cell collection. The most common and transient side effects from stem cell donation are fatigue, headache, bone and muscle pain. Major side effects are rare but there is a small risk of fatalities and serious adverse events. To facilitate the provision of adequate information and care of patients undergoing HSCT and their sibling donors there is a need to explore and study their situations and experiences. This thesis aims to investigate patients’ and sibling donors’ perspectives of HSCT. The first study investigated changes in the patients’ quality of life (QoL) from before HSCT to 100 days and 12 months after the transplantation, and identified factors associated with the changes. The study was completed by 40 patients who answered the questionnaires (FACT-BMT and FACIT-Sp) on all three occasions. The majority of the dimensions covered in QoL deteriorated from before and up to 100 days and 12 months after HSCT, except for the emotional well-being which improved. The factors associated with reduced QoL over time were significant infections, female gender and transplantation with stem cells from a sibling donor. Factors associated with improved emotional well-being over time were absence of significant infections and marital status ‘other than married/cohabiting’. In the second study an information and care model (IC model) for potential sibling stem cell donors was evaluated. A questionnaire survey was answered by 148 siblings who had been informed about and asked to undergo HLA typing by the IC model. The majority of the potential sibling donors were satisfied with the information and care they had received. However, areas for improvement were highlighted, such as a wish to have the results from the HLA typing conveyed through personal contact and that the complicating influence of health professionals and relatives on their decision to undergo HLA typing and possible donation could be prevented. In the third study ten HSCT patients were interviewed immediately before transplantation regarding their experiences of having a sibling as donor. The results, with the main theme Being in no man’s land, show that the patients are in a complex situation before transplantation, experiencing a mixture of emotions and thoughts. In the fourth study ten sibling donors, where the recipients were the participants in Study III, were interviewed regarding their experiences before donation of being a stem cell donor for a sick sibling. The main theme, Being a cog in a big wheel, in the results shows that the sibling donors go through a complex process before donation, a situation they have not volunteered for but have got into accidently, experiencing a mixture of emotions and thoughts. The results also show that the sibling donors do not usually reveal their thoughts and emotions about being a donor to anyone. The patients’ and sibling donors’ experiences can be seen to be connected to each other, however, they have not usually talked to each other about their emotions and thoughts. To conclude, HSCT patients’ overall QoL and the majority of the dimensions of QoL deteriorated from before until 100 days and 12 months after HSCT, while their emotional well-being improved. The privacy and free choice of potential sibling donors have to be respected and the information and care of patients and their sibling donors should be kept separate. Health professionals should bear in mind that both patients with a sibling as donor and sibling donors are in complex situations before transplantation and donation, experiencing a mixture of emotions and thoughts. Further, it is important to individualize the information and care for HSCT patients and their sibling donors in a supportive and professional manner.
10.
  • Mahmood Jallal Hadi, Deyar (författare)
  • On core and bi-layered all-ceramic fixed dental prostheses, design and mechanical properties : studies on stabilized zirconiumdioxide
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Loss of teeth can affect a person’s self-esteem, social life, appearance and oral function. Reconstruction of a missing tooth has scientifically been shown to increase self-esteem and quality of life and to maintain oral function. For many patients a fixed dental prostheses (FDP) is preferred, either tooth- or implant-supported. Improvement and development of all-ceramic materials have made them preferable to other alternatives. However, despite properties of dental ceramics’ well known biocompatibility, good chemical and mechanical, the materials have their weaknesses, such as brittleness and some difficulties with the layering porcelain. Many all-ceramic materials cannot withstand minor flexure; more than 0.1 - 0.3 %, will lead to fracture. Oxide-ceramic, specifically yttria stabilized tetragonal zirconia polycrystals (Y-TZP) has become the most commonly used all-ceramic material. This material has the potential to be used for larger restorations. In addition, one of many challenges is to ensure durable zirconia-based restorations in the oral cavity. In the clinical situation, crowns and bridges are supported by a combination of different structures with differing properties, i.e. bone, dentine and enamel. The complexity of the supporting tissues in the oral cavity creates stress patterns in the prosthetic material, which need to be considered when designing a dental restoration. The durability of all-ceramic FDPs is dependent on knowledge of the material and design of the FDPs. In particular the design, shape of the connector and the radius of curvature at the gingival embrasure play a significant role in the load-bearing capacity of FDPs. The overall aim of this thesis is to evaluate design of zirconia-based restorations in relation to achieving increased fracture resistance. Another aim is related to how the choice of material used for supporting tooth analogues in the test set-up and how this influences test results relating to fracture strength of all-ceramic FDPs. Study I evaluates different radii (0.60 and 0.90 mm) of curvature in the embrasure of the connector area and different connector dimensions (2 x 2, 3 x 2 and 3 x 3 mm) and their effects on the fracture resistance of 3-unit all-ceramic FPDs made of Y-TZP. The results show that by increasing the radius of the gingival embrasure from 0.6 to 0.9 mm, the fracture strength for a Y-TZP FPD with connector dimension 3 x 3 mm will increase by 20%. Study II investigated how the choice of material (aluminium, polymer and DuraLay) used for supporting tooth analogues and support complexity influence test results concerning the fracture strength of FDPs made of a brittle material Y-TZP. The outcome of the study demonstrated that Y-TZP FDPs cemented on tooth analogues made of aluminium, with high E-modulus showed a significantly higher load at fracture and a different fracture mode than shown in clinical situations. Study III evaluates how factors as different default settings for connector design of two different CAD/CAM systems and different radii of curvature in the embrasure area of the connector will affect the fracture strength and the fracture mode of 3-unit, i.e. 4-unit allceramic FDPs made from Y-TZP and further to investigate how the number of pontics affect the fracture strength of Y-TZP. The results showed that the most crucial factor for the load-bearing capacity is the design of the radius of the gingival embrasures. Increasing the number of pontics from three to four decreases the load-bearing capacity nearly twice. Study IV investigate and compare the fracture strength and fracture mode in 11 groups of the currently most used multilayer all-ceramic systems for Y-TZP FDPs, with respect to the choice of core material, veneering material area, manufacturing technique (split-file, overpress, built-up porcelains and glass-ceramics), design of connectors and radius of curvature of FDP cores. The results show that the design of a framework is a crucial factor for the load bearing capacity of an all-ceramic FDP. The state-of-the-art designs are preferable, since the split-file designed cores call for a cross-sectional connector area, at least 42% larger, to have the same load bearing capacity as the state-of-the-art designed cores. Analyses of the fracture patterns demonstrated differences between the milled veneers and over-pressed or built-up veneers, where the milled ones showed numerically more veneer cracks whereas the other groups only showed complete connector fractures. All veneering materials/techniques tested were found, with great safety margin to be sufficient for clinical use both anteriorly and posteriorly.
11.
  • Maimaitiyili, Tuerdi (författare)
  • Phase transformation and stability studies of the Zr-H system
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Popular Abstract in English Zirconium alloys are widely used in nuclear power reactors as cladding material for their fuels due to the high strength, good corrosion resistance and low neutron absorption cross-section, even in extreme environment, that is characteristic for zirconium. The element, however, also has strong affinity for hydrogen, and when both are present they readily react and form a family of compounds called hydrides. It is well known that even small amounts of hydrides in zirconium based materials will cause the material to loose ductility, making it brittle, and susceptible to cracking. In the case of nuclear fuel, these zirconium based alloys are not only the cladding of uranium fuels in the reactors but also the first barrier of defense of nuclear waste and radioactive substance in general, and as such the problem of hydrogen absorption and hydrides formation becomes significant and important to study. Despite the fact that zirconium hydrides have been extensively studied for about half a century, the basic nature and mechanisms of hydride formation, the transformation between various phases of hydride, and their exact crystal structures are not yet fully understood. In order to find answer to some of these problems, the precipitation and dissolution, that is the formation and removal, of hydrides, in pure zirconium powder were carried out and studied. The processes were monitored in real time using high resolution synchrotron and neutron radiations, whereby whole diffraction patterns of crystal structures where recorded of zirconium and the hydrides. These patterns were used in the analysis of the environments and conditions that are important for the formation of hydrides, as well as to answer questions about the mechanisms and speed with which these events occur. Based on the observations during these experiments, and the results of the analysis, a better understanding of the behavior of different hydride phases has been achieved. In particular during thermal treatment and in-situ hydrogenation compared to those being reported in literature. Some new findings were also reported. The main ones being: 1. All commonly reported zirconium hydride phases were recorded, for the first time, in a single in-situ experiment. 2. The complete reversible transformation between two different zirconium hydride phases was observed. 3. The phase transformation type between two commonly reported zirconium hydrides, called delta and epsilon, was analyzed and defined. 4. The preparation route of a controversial zirconium hydride, known as gamma zirconium hydride, is introduced and its exact crystal structure and formation mechanisms are also discussed in detail.
12.
  • Palm, Peter, 1977- (författare)
  • Challenges of Commercial Real Estate Management An analysis of the Swedish commercial real estate industry
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Avhandlingen består av fem artiklar som var och en adresserar ett specifikt område inom förvaltning av kommersiella fastigheter. Det övergripande syftet med avhandlingen är att se till de utmaningar förvaltning av kommersiella fastigheter innebär. De två första artiklarna utgör en plattform för resten av avhandlingen och är en kartläggning av branschen. Artikel I fokuserar på branschens kund och service medvetenhet i deras årsredovisningar. Artikel II är en uppföljande intervjustudie av företagen i artikel I gällande ledningens uppfattning gällande vilka organisations frågor som är av strategisk natur för att leverera god kundservice. Tredje artikeln adresserar kontorsmarknaden och hur fastighetsägarens organisatoriska attribut påverkar annonseringstiden av kontorslokaler. Den testar eventualiteten att internet som marknadsplats för uthyrning av kontor är en så kallad lemons market, där företrädelsevis ”dåliga” objekt marknadsförs. De två sista artiklarna studerar sedan incitament i förvaltningsorganisationen om den bedrivs in-house eller är outsourcad. Den första av dessa två berör specifikt hur incitament för att genomföra arbetsuppgifter regleras och den andra artikeln ser istället till hur beslutsfattaren säkerställer sig information från förvaltningen för att kunna ta väl informerade beslut. I första artikeln får vi med oss att den kommersiella fastighetsmarknaden i Sverige är kundorienterad. Vi kan konstatera att branschen redan före 2004 hade gjort skiftet från produkt orientering till kund/service orientering. Däremot kunde vi inte konstatera att kundfokus hade ökat i företagens årsredovisningar mellan åren 2004-2008. Slutsatsen från artikel II är att oavsett förvaltningsorganisation, in-house eller outsourcad, är argumentationen från ledningen i dessa företag att val av organisering av förvaltningen är bottnad i service leveransen till deras kunder/hyresgäster. Tredje artikeln är ett test av internet som marknadsplats för kontor i Malö CBD där teorin om market for lemons testas. Organisering av förvaltningen var en av kvalitetssignalerna, tillsammans med storlek, kontor på orten och om företaget varit i Hyresnämnden. Slutsatsen är att vi inte kan förkasta hypotesen om att marknadsplatsen är en market for lemons. Slutsatsen från artikel IV och V lyfter fram skillnaden i hur incitament skapar i förvaltningsorganisationerna, då den är organiserad in-house alternativt outsourcad. Förvaltningen i outsourcade organisationer regleras primärt av kontraktet, mellan ägarbolaget och service bolaget som de är anställda av, där det stipuleras när och hur de förväntas leverera såväl information som kund service. Förvaltningen i företagen med in-house förvaltning arbetar istället genom frihet under ansvar där de bedöms genom resultatet av deras service istället för genom checklistor och Job beskrivningar. Oavsett organisering av förvaltningen så finns där inte några monetära incitament för förvaltaren som baseras direkt på deras individuella prestationer.
13.
  • Rönnbäck, Julia (författare)
  • Det är väl typiskt tjejer : om basket, kropp och femininitet
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • The aim of this dissertation is to analyse how a group of female basketball players – aged 15 to 18 and located in one of Sweden’s largest cities – construct and negotiate gender and femininity through bodily and verbal practices. The study is grounded in poststructuralist theories – primarily using the theoretical work of the philosophers Judith Butler and Michel Foucault. The methods used are qualitative: participant observations, interviews and written dialogues via Facebook. The writing method used is ethnographic fiction. The first part of the analysis shows how the female basketball players frequently talk about appearance and also how they repeatedly talk about the fleshier matters of the body – such as muscles and fat. These recurrent verbal practices are parts of the processes through which the girls construct gender and femininity, and a way of exercising relational power. The girls themselves explain their frequent talk about body and appearance as something “typical” for girls and thus they use a discourse that circles them (as young women) in order to make themselves understandable. The second part of the analysis depicts how the female basketball players – in the locker room – before every game construct similar and socially recognizable female bodies. These recurrent bodily practices are further parts of the processes through which the girls construct gender and femininity. Additionally, in the second part, the analysis show how the female basketball players – through verbal and bodily practices – transform gender and convert femininity within sport and also how they, in game situations, embody two different discourses: “Girl Power” and “the insecure (sporting) girl” that encompass young (sporting) women. One conclusion in the thesis is that discourses that surround young (sporting) females appear to be central in their creation of gender identity. Furthermore, the (sporting) girls are active participants in the ongoing debate regarding what (sporting) girls are, can be and should be.
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14.
  • Serder, Margareta (författare)
  • Möten med PISA : kunskapsmätning som samspel mellan elever och provuppgifter i och om naturvetenskap
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • This thesis explores the standardized assessment of students’ scientific literacy by studying test items, frameworks and result reports from the international comparative study Programme for International Student Assessment, PISA. My research concerns the negative trend observed for Swedish students’ results in science reported in international comparisons since 2000. In this thesis, PISA is considered as a specific kind of practice that acts through a certain rationality, which frames how the measurement is constructed and interpreted. The overall aim is to highlight the epistemological and ontological assumptions that are embedded in the assessment of students’ scientific literacy by PISA. Data was constructed by video documentation of collaborative encounters between 21 groups of 15-year-old students and eleven selected items from the PISA scientific literacy assessment. This method enabled an analysis of the students’ reasoning and the difficulties that arose in these encounters. I also conducted a text analysis of selected frameworks and reports produced under the PISA label, analyzing how science and student performance are discursively constructed in these documents. In this thesis, I examine the similarities and differences between two theoretical approaches: one sociocultural and one sociomaterial. Both are used to explore the embedded assumptions of the PISA scientific literacy assessment. The sociocultural perspective focuses on the students’ situated meaning making as they solve the test questions. The sociomaterial perspective finds inspiration in science and technology studies, and takes a performative stance on scientific practice. This thesis has been formed as a hybrid of a compilation thesis and a monograph. It comprises three articles in English, published or still in the process of publication. The measured knowledge in and about science in PISA are based on onto-epistemological assumptions that are connected to science traditions which are mainly monologistic and representational, whereas this thesis proposes a dialogistic and performative stance. One identified assumption is that language is a neutral transmitter of information, which can be unambiguously communicated and translated without losing or gaining new meanings. Another is the assumption of a single unambiguous, primary frame for interpretation of the test questions, and a third that in PISA, science is assumed to be a socially and culturally neutral object for learning. It appears crucial that the students are able, and motivated, to discern and privilege the scientific perspectives and interpretations while engaging with the complexity of the tasks. My analysis suggests that framing the tasks within fictive, everyday situations, as is significant for PISA, contributes to this complexity. Further, the image of science as portrayed in the test items that were studied, risk reproducing stereotypical images of science and scientifically literate people. To PISA, students are mirrors of the school system and even future society. In the analysis of PISA documents, low performers appeared as threats to future society, due to the risk that they would become ineffective citizens. Meanwhile, other studies assert that standardized comparison is a practice that, when frequently repeated, contributes to lower results and an increasing disillusion of low achievers. It is proposed that PISA, rather than to be seen as a knowledge measurement, should be regarded a knowledge actor.
15.
  • Weiber, Ingrid (författare)
  • Children in families where the mother has an intellectual or developmental disability : incidence, support and first person narratives
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • The aim of this thesis was to increase the knowledge about children born to mothers with an intellectual or developmental disability by investigating incidence (Study I), support at the stra tegic level (Study II), support at the family level (Study III), and experiences of having grown up with a mother with a developmental disability (Study IV). The first study investigated the 5-year incidence of children being born to mothers with an intellectua l disability in a Swedish county. Three types of registers were used, together with personal identification numbers. The resulting incidence rate, 2.12 children per 1,000 children indicates that there are currently approximately 4000 children (aged 0-18 years) that have been born to a mother with an intellectual disability in Sweden. Data for Studies II and III were collect ed by means of focus group interviews with 29 professionals supporting families with parental intellectual disability, and the data were analysed by means of content analysis. Study II described results on the strategic level of support; roles and activities of the professionals involved, identification of families in need, problems with identifying mothers with an intellectual disability, existing collaboration and dilemmas concerning legislative actions. The results indicated a rich web of support to these families from all kinds of welfare sectors, but further needs for building collaboration were identified, such as the need to coordinate education efforts. Study III described results on the family level of support: support practices, pedagogical strategies, and maintaining the child perspective. The results indicated the need for concrete training, the importance of involving the father/ partner, and the value of not losing the child perspective and of creating support practices with a clearer focus on the children. In Study IV, four women were interviewed about their experiences of growing up in a family with a mother who has a developmental disability. Narrative inquiry and content analysis were employed. The findings showed recollections of a vulnerable childhood filled with worries, fear, and anxiety, and with a strong feeling of responsibility. No effective support from the authorities was ever offered to the four informants, who dealt differently with their lives as adults with regard to their own family and children. The results of this thesis provide new knowledge about the complex situation of being a child in a family with maternal intellectual or developmental disability, and they may be used by staff in the welfare sectors in order to improve the visibility of these children and offer support adapted to the children's situation.
16.
  • Wiedel, Anna-Paulina (författare)
  • Fixed or removable appliance for early orthodontic treatment of functional anterior crossbite : evidence-based evaluations of success rate of interventions, treatment stability, cost-effectiveness and patients perceptions
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Anterior crossbite with functional shift also called pseudo Class III is a malocclusion in which the incisal edges of one or more maxillary incisors occlude with the incisal edges of the mandibular incisors in centric relationship: the mandible and mandibular incisors are then guided anteriorly in central occlusion resulting in an anterior crossbite.Early correction, at the mixed dentition stage, is recommended, in order to avoid a compromising dentofacial condition which could result in the development of a true Class III malocclusion and temporomandibular symptoms. Various treatment options are available. The method of choice for orthodontic correction of this condition should not only be clinically effective, with long-term stability, but also cost-effective and have high patient acceptance, i.e. minimal perceived pain and discomfort. At the mixed dentition stage, the condition may be treated by fixed (FA) or removable appliance (RA). To date there is insufficient evidence to determine the preferred method.The overall aim of this thesis was therefore to compare and evaluate the use of FA and RA for correcting anterior crossbite with functional shift in the mixed dentition, with special reference to clinical effectiveness, stability, cost-effectiveness and patient perceptions. Evidence-based, randomized controlled trial (RCT) methodology was used, in order to generate a high level of evidence. The thesis is based on the following studies: The material comprised 64 patients, consecutively recruited from the Department of Orthodontics, Faculty of Odontology, Malmö University, Sweden and from one Public Dental Health Service Clinic in Malmö, Skane County Council, Sweden. The patients were no syndrome and no cleft patients. The following inclusion criteria were applied: early to late mixed dentition, anterior crossbite affecting one or more incisors with functional shift, moderate space deficiency in the maxilla, no inherent skeletal Class III discrepancy, ANB angle> 0º, and no previous orthodontic treatment. Sixty-two patients agreed to participate and were randomly allocated for treatment either with FA with brackets and wires, or RA, comprising acrylic plates with protruding springs. Paper I compared and evaluated the efficiency of the two different treatment strategies to correct the anterior crossbite with anterior shift in mixed dentition. Paper II compared and evaluated the stability of the results of the two treatment methods two years after the appliances were removed. In Paper III, the cost-effectiveness of the two treatment methods was compared and evaluated by costminimization analysis. Paper IV evaluated and compared the patient´s perceptions of the two treatment methods, in terms of perceived pain, discomfort and impairment of jaw function. The following conclusions were drawn from the results: Paper I • Anterior crossbite with functional shift in the mixed dentition can be successfully corrected by either fixed or removable appliance therapy in a short-term perspective. • Treatment time for correction of anterior crossbite with functional shift was significantly shorter for FA compared to RA but the difference had minor clinical relevance. Paper II • In the mixed dentition, anterior crossbite affecting one or more incisors can be successfully corrected by either fixed or removable appliances, with similarly stable outcomes and equally favourable prognoses. • Either type of appliance can be recommended. Paper III • Correction of anterior crossbite with functional shift using fixed appliance offers significant economic benefits over removable appliances, including lower direct costs for materials and lower indirect costs. Even when only successful outcomes are considered, treatment with removable appliance is more expensive. Paper IV • The general levels of pain intensity and discomfort were low to moderate in both groups. • The level of pain and discomfort intensity was higher for the first three days in the fixed appliance group, and peaked on day two for both appliances. • Adverse effects on school and leisure activities as well as speech difficulties were more pronounced in the removable than in the fixed appliance group, whereas in the fixed appliance group, patients reported more difficulty eating different kinds of hard food. • Thus, while there were some statistically significant differences between patients´ perceptions of fixed and removable appliances but these differences were only minor and seems to have minor clinical relevance. As fixed and removable appliances were generally well accepted by the patients, both methods of treatment can be recommended. Key conclusions and clinical implications Four outcome measures were evaluated: -success rate of treatment, treatment stability, cost-effectiveness and patient acceptance, which is important from both patient and care giver perspectives. It is concluded that both methods have high success rates, demonstrate good long-term stability and are well accepted by the patients. Treatment by removable appliance is the more expensive alternative. Thus, in the studies on which this thesis is based, fixed appliance emerges as the preferred approach to correction of anterior crossbite with functional shift in the mixed dentition.
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