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Sökning: mat:dok lärosäte:mau 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.
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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 developimproved biomaterials is progressing rapidly.Of specific interest is to accelerate bone formation around theimplant surface, which could improve the reliability of the implanteven in patients with compromised situations. Although the surfacemodification of the implant has been proven to certain extent topromote osseointegration, the lack of bone in the patient remains amajor issue and bone augmentation is commonly conducted priorto implant insertion. Synthetic and naturally derived resorbablematerials are commonly used. However, problems such as the lackof optimal mechanical properties or the undesirable materialresorption kinetics still exist and there still remain possibility forimprovement. Clinical approaches for orthopaedic trauma require the use ofnon-resorbable screws, plates and pins made of metallic materialssuch as titanium, cobalt-chrome and stainless steel alloys. Themajor drawback of these materials is the need of implant removalat re-entry. Therefore, the research of bioresorbable materials thatcould withstand the mechanical stresses is an ongoing topic.Based on this clinical reality, the aim of this thesis was toinvestigate the suitability of magnesium (Mg) as a biomaterial forregenerative bone applications. Namely, Mg as a doping materialfor engineered mesoporous titanium implant surfaces (Studies I, IIand III), and as a bioresorbable metal alloy for bone regenerationin bone trauma and bone defects conditions (Study IV).Study I, II, IIIMesoporous titania films produced with evaporation-induced selfassembly(EISA) technique and applied as implant surface coatingsare under investigation as a release system for the controlledadministration of several substances, such as osteoporotic drugs, toenhance early bone anchorage to the implant. Modulating the poresize of such films though the selection of EISA parameters permitsto control the adsorption of such substances into the mesoporousmatrix and their subsequent release into the peri-implant region.Studies I, II and III analysed the effect of Mg incorporation intomesoporous titania coatings towards two cellular models duringearly and later stages of cell activity.Study I characterized the morphology, chemistry, and topographyof mesoporous titania coatings and the effects of Mg-loading onsurface micro- and nano-structures. Mg release was determinedand its effect was evaluated on human foetal osteoblast populations.It was shown that mesoporous films possessed a smoothsurface with pores that faced outward. Mg adsorption did notsubstantially alter the mesoporous surface roughness both atmicro- and nano- levels. Mg was released within 24 hours ofincubation in cell culture conditions, thus its bioactive effect onlyoccurred during initial osteoblasts activity.Study II evaluated the ability of Mg-loaded mesoporous coatings tomodulate multipotent adipose-derived stromal cell differentiationtoward the osteoblast phenotype. The results demonstrated thatMg release had a strong impact on this cellular model, promotingosteoblast marker expression in standard cell culture conditions.Interestingly, Mg significantly promoted the expression of osteopontin,a protein that is essential for early biomaterial-cellosteogenic interaction.In study III, the reagents and EISA parameters in the mesoporousdeposition were varied to generate three mesoporous titaniacoatings with 2-, 6- and 7-nm average pore size, to increase Mgcontent in the interconnected porosity of the films. The effect ofvarious Mg contents released from the three mesoporous structureswas tested on human foetal osteoblasts populations with pre-designedosteogenic PCR arrays and real-time polymerase chainreaction. It was shown that Mg release affected osteogenesis andwas controlled by tuning the pore dimensions of the mesoporousfilms. Increasing pore size by 1 nm (from 6 nm to 7 nm)significantly enhanced the bioactivity of the film without alteringthe surface roughness.Study IVIn orthopaedics Mg alloys has received increasing attention asbioresorbable metals for bone regeneration. However, localizedmaterial degradation is too fast and provokes the premature loss ofmechanical properties, preventing correct cellular development andbone healing in vivo . For this reason, various alloying elements arecombined with high-purity Mg to modulate and optimize degradationbehaviour.Study IV of this thesis investigated the degradation parameters ofMg2Ag, Mg10Gd, and Mg4Y3RE alloys and how the alloysdifferently affect human umbilical cord perivascular cell adhesionand spreading. Mg4Y3RE showed the highest degradation rateand, thereby, the highest trend in increases in pH and osmolality ofthe surrounding fluid. However, both Mg4Y3RE and Mg10Gdallowed cells to better adhere and spread across their degradedsurfaces; in comparison, surface degradation of Mg2Ag was moreaggressive with weak or no visible cellular structures on it.ConclusionsIn summary, the results of the present thesis explored the potentialof Mg for its application in bone tissue regeneration. Titaniumimplant surfaces coated with mesoporous TiO2 thin films andfurther loaded with Mg enhanced bone cell activity and osteoprogenitordevelopment into mature osteoblasts. Thus, mesoporousdeposition followed by Mg loading may be a suitablealternative to existing implant surface treatments.Bioresorbable materials must degrade slowly and uniformly inorder to simulate the tissue healing process. Mg10Gd possessesreduced content of alloying element and a suitable homogenousdegradation pattern in vitro that allows proper adhesion ofundifferentiated cells. Mg10Gd thus represents a biodegradableMg-based material with promising mechanical and biologicalproperties for use in dental and orthopaedic fields.
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3.
  • Cory, Erin, 1980- (författare)
  • Re-Membering Beirut : Performing Memory and Community Across a 'Postwar' City
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • More than 20 years after the end of Lebanon’s civil war (1975-1990), reconciliation remains elusive. A number of factors contribute to this stasis. No agreed-upon historical narrative exists by which Lebanon’s 18 ethnoreligious groups can make sense of the war, and the state has interests – both economic and political – for burying common memories and erasing common spaces. In light of these erasures, the capital Beirut, like much of the country, remains divided along spatial, ideological, and mnemonic lines.The extant literature has generally considered the perils of what Samir Khalaf (2006) calls Beirut’s “geography of fear.” By contrast, this dissertation considers the city a realm of possibility. “Re-membering Beirut: Performing Memory and Community Across a ‘Postwar’ City,” fuses ethnographic research, analysis, and performative writing to introduce the ide of “re-membering,” a term I use to describe how people engage the residual material of the city-at-war – its textures, tempos, routes, and representations – to render legible the shared pasts and current political claims of historically divided communities. Through case studies including a walking tour, a protest, and street art, I argue for considering the city’s in-between spaces as loci for emergent cross-communal politics, and for movement as both object of analysis and method. The sometimes ephemeral publics that take shape around these performances and practices reconfigure how Beirutis understand themselves in relation to their city and each other, whilc simultaneously revealing the city’s persistent ideological and spatial terrain.The project contributes to a fuller picture of how people across the Middle East and North Africa (the MENA region) are using urban space and cultural production – in the wake of the Arab revolutions and most urgently in the midst of the ongoing Syrian crisis – to communicate shared pain and dissent, and to mobilize in the face of failing or oppressive political systems. As the region once again divides itself along both old and new fault lines, the study explores the perils of occluding violent histories, as well as the critical role of culture in inter-communal postwar healing.
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4.
  • 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 malocclusionsand possible self-correction of malocclusions during the developmentof the dentition. Early intervention might be unnecessary if self-correction of the malocclusion occurs during the transition from theprimary to the permanent dentition. Most studies are cross-sectionaland in those of longitudinal design, the results are inconsistent anddifficult to interpret.Malocclusions may or may not influence the quality of life inchildren and adolescents. Thus, evaluations of the influence ofdifferent malocclusions on quality of life will certainly underpin abroader understanding and knowledge about how malocclusionsaffect the daily life of young patients. This information may also beimportant when it comes to assessing the most appropriate time forstarting orthodontic treatment, not only from a professional pointof view, but also, most importantly, from the patients’ perspective.The overall aim of this thesis was therefore to evaluate theprevalence of malocclusions, and to document changes occurringduring the development of the dentition, from the primary dentitionstage at age 3, through the mixed dentition at age 7, to the earlypermanent dentition at age 11.5 years. Further aims were to reviewthe current state of knowledge about the impact of malocclusionson oral health related quality of life (OHRQoL) and to investigatehow malocclusions affect the quality of life in a cohort of children,aged 11.5 years, whose dental care is provided by the Swedish PublicDental Service.
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5.
  • 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.
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6.
  • 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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7.
  • Halldin, Anders (författare)
  • On a biomechanical approach to analysis of stability and load bearing capacity of oral implants
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • IntroductionWhen an implant is placed in the bone the body responds to thetrauma by encapsulating the implant and its survival depends onthe ability for hard tissue encapsulation. The stability of the implantduring the healing phase is essential to achieve a good result[1]. Biological, physiological and mechanical phenomena affectimplant stability. To achieve sufficient stability during the initialhealing phase the implant has to provide sufficient static interactionwith the bone. The static interaction might affect the biologicalprocesses that in turn affect implant stability. Although, numerousstudies on the effect of dynamic interaction on implant stabilityand bone remodeling exist, the effect of static strain has yetto be clarified.As the healing progresses it may result in bone formation in closecontact with the implant (i.e osseointegration) that stabilizes theimplant. It has been found that implant surface modifications atthe micro level promote osseointegration and that moderatelyroughened implants provide rapid and strong bone response [2, 3].In addition, the application of nanostructures to an implant surfacehas been shown to elicit an initial complex gene response that mayresult in further enhancement in bone formation around the implant[4]. Furthermore the implant surface structure interlocks mechanicallywith the bone that affects the stability of the implant.The implant surface design has to take into account both biologicaland mechanical behavior of the tissues.Materials and methodsTo investigate how implant stability and the biological responseare affected by an induced static load to the bone an in vivo studywas performed. Two types of controlled static loads, excessive andmoderate, were induced by specially designed implants. Two typesof surface structure, turned and blasted, were applied on the implants.The implants were inserted in rabbits and healed for 3-84days before the stability was measured by removal torque.To simulate how the pressure changes, due to biological and mechanicalphenomena, on an implant surface that was subjected toan initial pressure, a constitutive model was developed that wascomprised 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 responsesare affected by the surface structure an in vivo study and a finiteelement analysis of the theoretical interfacial shear strength wereperformed. In the pre-clinical study, three groups of implants withdifferent nano- and microstructures were compared to an implantwith a control surface structure.The theoretical interfacial strength at different healing times wasestimated by simulating the surface structure interlocking capacityto bone using an explicit finite element method. Simulations wereperformed for different surface structures and for different pressures,simulating visco-elastic and remodeling phenomena.ResultsImplants that induced a moderate bone condensation in the bonehad a significantly higher removal torque value at the implantationtimes of 3-24 days compared to implants that did not induce condensation.The effect the induced moderate bone condensation hadon 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 condensationresulted in significant increased implant stability at implantationtimes of 3-24 days compared to implants that induced no condensation.However, when they were placed in femur it provided nosignificant difference in removal torque at an implantation time of24 days compared to implants that induced no condensation.The developed constitutive model is able to capture visco-elasticmaterial behavior and remodeling phenomena of cortical bonewhich can be used to simulate how the pressure changes on an implantsurface that is subjected to an initial pressure caused by condensation.The implant nano- and microsurface structure affects the magnitudeof the removal torque value. It was found that implants, withno significant difference in surface roughness parameters (Sa, Ssk,Sdr) on micro level, can present a significant difference in removaltorque value at 4 weeks of implantation time. In addition, it wasalso found that implants with a significant difference in surfaceroughness parameters (Sa, Ssk, Sdr) can present no significant differencein removal torque value at 4 weeks of implantation times. Thedifference may be due to various biological responses from thenano- and microstructure surfaces.The simulated interfacial strength for the different surfaces did notreach the interfacial strength that corresponds to the removaltorque obtained in the in vivo study. Comparing the two surfaces in respect of removal torque ratio, suggests that during the earlyhealing phase the difference is caused by different bone formationrates from biological processes. As the healing progresses the effectof structural interlocking capacity is more pronounced.ConclusionsThe results suggest that increased static strain in the bone not onlycreates higher implant stability at the time of insertion, but alsogenerates increased implant stability throughout the observationperiod of 3-24 days. The proposed constitutive material model consists of three differentcomponents: a visco-elastic component, a visco-plastic componentand a remodeling component. The model captures with goodagreement the experimental behavior of cortical bone during differentlongitudinal 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 microstructurealteration on a blasted implant might enhance the initial biomechanicalperformance, while for longer healing times, the surfaceinterlocking capacity seems to be more important.Simulation of the interfacial shear strength by means of finite elementanalysis seems to be a promising method to estimate the loadbearing capacity of the bone-to-implant interface for different surfacestructures at stable healing conditions i.e. longer healing times.Furthermore, it is a promising method to estimate the implant stabilityfor different magnitudes of condensation.
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8.
  • 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.
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9.
  • Hasslöf, Helen, 1961- (författare)
  • The educational challenge in "education for sustainable development" : Qualification, social change and the political
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • What happens with the aims and purposes of education when sustainability issues of complexity, uncertainty, risk and necessity are to be handled in educational practises? In this thesis Helen Hasslöf analyses how secondary and upper secondary school teachers discuss aims and purposes of their teaching practices in the light of sustainable development as an overarching perspective. Conflicting aims are problematized to discuss purposes of education. The included articles thus elaborate on students’ possibilities to develop as political subjects, how to value what is seen as qualification of Education for Sustainable Development (ESD), and emerging myths of social change in relation to sustainability. Furthermore, the concept of sustainable development is elaborated from a conflict perspective in an educational setting. Theories and ideas from Bakhtin, Wertsch, Biesta and Laclau & Mouffe are important theoretical foundations. Analytical methods, inspired by discourse theory, are developed to be used for analysis of teachers’ meaning-making discussions.
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10.
  • 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.
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11.
  • 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.
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12.
  • Maimaitiyili, Tuerdi (författare)
  • Phase transformation and stability studies of the Zr-H system
  • 2015
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Zirconium alloys are widely used in the nuclear industry because of their high strength, good corrosion resistance and low neutron absorption cross-section. Zirconium has a strong affinity for hydrogen, however, and if hydrogen concentration builds up, the material will gradually degrade. In one class of such hydrogen caused degradation, called hydride induced embrittlement, hydrogen chemically reacts with zirconium forming one, or several, crystal phases of zirconium hydride. These hydrides play a primary, but sometime not fully understood, role in crack initiation and propagation within these materials. Despite the fact that hydride induced embrittlement in zirconium have been studied for several decades, there are still some unresolved issues. It has been the aim of the research presented in this thesis to provide the research community with new and updated data of the hydrides themselves in order to aid further studies within the field of hydride induced embrittlement in general, and the mechanism of delayed hydride cracking in particular. To that end, the research presented here proceeded, in short, as follows: First, zirconium hydride powder, of well defined hydrogen concentration, was produced from commercial grade zirconium. This powder was subjected to heat treatment and the hydride phases were characterized both in situ and ex situ using neutron, synchrotron X-ray, and conventional laboratory X-ray based diffraction techniques. Next, most of the low-pressure zirconium hydride phases were produced under hydrogen/argon atmosphere from commercial grade zirconium powder. This process was simultaneously monitored and recorded in real time using synchrotron X-ray diffraction. These experiments have produced new data of the behavior of different hydride phases during thermal treatment and in situ hydrogenation. For the first time all commonly reported zirconium hydride phases and the complete transformation between two different hydride phases were recorded with a single experimental arrangement. The phase transformation between δ and ε zirconium hydride was recorded in detail and presented. Finally, the controversial γ zirconium hydride was observed both in situ and ex situ and the preparation route, its crystal structure, and formation mechanisms were analyzed and presented.
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13.
  • Palm, Peter (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.
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14.
  • 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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15.
  • 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.
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16.
  • 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.
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17.
  • 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 isa malocclusion in which the incisal edges of one or more maxillaryincisors occlude with the incisal edges of the mandibular incisorsin centric relationship: the mandible and mandibular incisors arethen guided anteriorly in central occlusion resulting in an anteriorcrossbite.Early correction, at the mixed dentition stage, is recommended,in order to avoid a compromising dentofacial condition whichcould result in the development of a true Class III malocclusionand temporomandibular symptoms. Various treatment options areavailable. The method of choice for orthodontic correction of thiscondition should not only be clinically effective, with long-termstability, 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 preferredmethod.The overall aim of this thesis was therefore to compare andevaluate the use of FA and RA for correcting anterior crossbitewith functional shift in the mixed dentition, with special referenceto clinical effectiveness, stability, cost-effectiveness and patientperceptions. 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 fromthe Department of Orthodontics, Faculty of Odontology, Malmö University, Sweden and from one Public Dental Health Service Clinicin Malmö, Skane County Council, Sweden. The patients were nosyndrome and no cleft patients. The following inclusion criteria wereapplied: early to late mixed dentition, anterior crossbite affecting oneor more incisors with functional shift, moderate space deficiency inthe maxilla, no inherent skeletal Class III discrepancy, ANB angle>0º, and no previous orthodontic treatment. Sixty-two patients agreedto participate and were randomly allocated for treatment either withFA with brackets and wires, or RA, comprising acrylic plates withprotruding springs. Paper I compared and evaluated the efficiency of the two differenttreatment strategies to correct the anterior crossbite with anteriorshift in mixed dentition. Paper II compared and evaluated thestability of the results of the two treatment methods two years afterthe appliances were removed. In Paper III, the cost-effectiveness ofthe two treatment methods was compared and evaluated by costminimizationanalysis. Paper IV evaluated and compared the patient´sperceptions 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 dentitioncan be successfully corrected by either fixed or removableappliance therapy in a short-term perspective.• Treatment time for correction of anterior crossbite withfunctional shift was significantly shorter for FA compared toRA but the difference had minor clinical relevance. Paper II• In the mixed dentition, anterior crossbite affecting one ormore incisors can be successfully corrected by either fixedor removable appliances, with similarly stable outcomes andequally favourable prognoses.• Either type of appliance can be recommended. Paper III• Correction of anterior crossbite with functional shift usingfixed appliance offers significant economic benefits overremovable appliances, including lower direct costs formaterials and lower indirect costs. Even when only successfuloutcomes are considered, treatment with removable applianceis more expensive. Paper IV• The general levels of pain intensity and discomfort were lowto moderate in both groups.• The level of pain and discomfort intensity was higher for thefirst three days in the fixed appliance group, and peaked onday two for both appliances.• Adverse effects on school and leisure activities as well asspeech difficulties were more pronounced in the removablethan in the fixed appliance group, whereas in the fixedappliance group, patients reported more difficulty eatingdifferent kinds of hard food.• Thus, while there were some statistically significant differences between patients´ perceptions of fixed and removableappliances but these differences were only minor and seemsto have minor clinical relevance. As fixed and removableappliances were generally well accepted by the patients, bothmethods of treatment can be recommended. Key conclusions and clinical implicationsFour outcome measures were evaluated: -success rate oftreatment, treatment stability, cost-effectiveness and patientacceptance, which is important from both patient and caregiver perspectives. It is concluded that both methods have highsuccess rates, demonstrate good long-term stability and are wellaccepted by the patients. Treatment by removable appliance isthe more expensive alternative. Thus, in the studies on whichthis thesis is based, fixed appliance emerges as the preferredapproach to correction of anterior crossbite with functionalshift in the mixed dentition.
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