189 research outputs found

    Terrestrialization, Miniaturization and Rates of Diversification in African Puddle Frogs (Anura: Phrynobatrachidae)

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    Terrestrialization, the evolution of non-aquatic oviposition, and miniaturization, the evolution of tiny adult body size, are recurring trends in amphibian evolution, but the relationships among the traits that characterize these phenomena are not well understood. Furthermore, these traits have been identified as possible “key innovations” that are predicted to increase rates of speciation in those lineages in which they evolve. We examine terrestrialization and miniaturization in sub-Saharan puddle frogs (Phrynobatrachidae) in a phylogenetic context to investigate the relationship between adaptation and diversification through time. We use relative dating techniques to ascertain if character trait shifts are associated with increased diversification rates, and we evaluate the likelihood that a single temporal event can explain the evolution of those traits. Results indicate alternate reproductive modes evolved independently in Phrynobatrachus at least seven times, including terrestrial deposition of eggs and terrestrial, non-feeding larvae. These shifts towards alternate reproductive modes are not linked to a common temporal event. Contrary to the “key innovations” hypothesis, clades that exhibit alternate reproductive modes have lower diversification rates than those that deposit eggs aquatically. Adult habitat, pedal webbing and body size have no effect on diversification rates. Though these traits putatively identified as key innovations for Phrynobatrachus do not seem to be associated with increased speciation rates, they may still provide opportunities to extend into new niches, thus increasing overall diversity

    Horrific images in East and West : A qualitative and comparative analysis of the visual representation of Syrian and Ukrainian refugees in three Swedish news outlets

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    This thesis compares the visual representation of Syrian refugees during the 2015 refugee crisis and Ukrainian refugees during the Russian invasion 2022 in news outlets Dagens Nyheter, Svenska Dabladet and Aftonbladet. The aim of the study is thus to investigate how ethnic groups are framed in a photojournalistic setting. The theoretical concept otherness is used to analyze the selected visual images and the concept of visualities highlight how photographs published in the media communicate political messages and how images reflect immigration discourse. Additionally, photojournalistic regimes of visibility and responsibility are used to illuminate similarities and dissimilarities in the material. In total, 200 images made up the sample for the performed qualitative visual analysis. The findings reveal that empathetic portrayals dominate the Swedish narrative. Syrian refugees were overrepresented in imagery alluding to otherness painting a picture of Syrians as ethnic, cultural and dangerous others. Photography triggering social and political engagement were crucial in the forming of visualities, relating visual images to the political and public arena. The sampled images did reflect immigration discourses of intimidation and humanity

    Horrific images in East and West : A qualitative and comparative analysis of the visual representation of Syrian and Ukrainian refugees in three Swedish news outlets

    No full text
    This thesis compares the visual representation of Syrian refugees during the 2015 refugee crisis and Ukrainian refugees during the Russian invasion 2022 in news outlets Dagens Nyheter, Svenska Dabladet and Aftonbladet. The aim of the study is thus to investigate how ethnic groups are framed in a photojournalistic setting. The theoretical concept otherness is used to analyze the selected visual images and the concept of visualities highlight how photographs published in the media communicate political messages and how images reflect immigration discourse. Additionally, photojournalistic regimes of visibility and responsibility are used to illuminate similarities and dissimilarities in the material. In total, 200 images made up the sample for the performed qualitative visual analysis. The findings reveal that empathetic portrayals dominate the Swedish narrative. Syrian refugees were overrepresented in imagery alluding to otherness painting a picture of Syrians as ethnic, cultural and dangerous others. Photography triggering social and political engagement were crucial in the forming of visualities, relating visual images to the political and public arena. The sampled images did reflect immigration discourses of intimidation and humanity

    Experiences of stigma amongst people with substance use disorder : a literature review

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    Bakgrund: Forskning har visat att stigma gentemot personer relaterat till sÀrskiljande egenskaper leder till försÀmrad hÀlsa för dessa individer. Sedan pionjÀren Erving Goffman 1963 formulerade sin teori om stigma har forskning kring stigma och personer med psykisk ohÀlsa grenat ut sig. Forskning har Àven influerat till att revolutionera förstÄelsen för substansbrukssyndrom, och hur det under det senaste seklet utvecklats frÄn tron att substansbrukssyndrom orsakas av moraliska brister till att det kan ses som en sjukdom som pÄverkar bÄde hjÀrna och beteende. Syfte: Syftet med litteraturstudien var att sammanstÀlla och belysa hur personer med substansbrukssyndrom upplever stigma. Metod: En systematisk kvalitativ litteraturstudie med induktiv ansats inspirerad av Polit och Becks niostegsmodell. Sjutton vetenskapliga artiklar söktes fram systematiskt, sammanstÀlldes och analyserades. Sökningar genomfördes i databaserna PubMed, Cinahl och Taylor & Francis. Resultat: Analysen utmynnade i fem kategorier som beskrev hur personer med substansbrukssyndrom upplevde stigma: att mötas av misstro och att inte bli tagen pÄ allvar, att endast ses för sitt substansbruk och inte som mÀnniska, att fÄ en sÀmre vÄrd Àn andra, att vÄrdpersonalen har negativt bemötande och att beskyllas för sin sjukdom. Slutsats: Att leva med substansbrukssyndrom innebÀr för individen ett dagligt möte med stigma. Litteraturstudiens resultat kan bidra med viktig kunskap om hur patienter med substansbrukssyndrom upplever möten i vÄrden. Detta kan öka kunskap och förstÄelse som i sin tur kan bidra till en förbÀttrad vÄrd för personer med substansbrukssyndrom dÀr lidande för individen minimeras och kostnader för samhÀllet minskas

    UtvÀrdering av temporÀra stödkonstruktioner

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    I byggnad och anlĂ€ggningsprojekt dĂ€r man avser att förĂ€ndra de ursprungliga geometriska förhĂ„llandena, till exempel genom schaktning, Ă€r det vanligt att nĂ„gon form av stödkonstruktion anvĂ€nds. Syftet med stödkonstruktionen Ă€r att förhindra att stabilitetsbrott uppstĂ„r i jorden, men Ă€ven att skydda nĂ€rliggande byggnader, anlĂ€ggningar och infrastruktur mot skadliga rörelser i jorden etc. Examensarbetet har bedrivits parallellt med ett verkligt uppdrag i Akershus, Norge Ă„t teknikkonsultföretaget Reinertsen AB. I uppdraget skall en sedimenteringsbassĂ€ng anlĂ€ggas med grundlĂ€ggningsnivĂ„ ca 4 Ă  4,5 m under befintlig markyta, vilket krĂ€ver nĂ„gon form av stödkonstruktion för att stabilisera schakten. Placeringen av sedimenteringsbassĂ€ngen Ă€r begrĂ€nsad till en liten yta dĂ€r bĂ„de vatten (i form av ett vattendrag) och berg omger konstruktionen. PĂ„ grund av den begrĂ€nsade ytan och nĂ€rheten till vatten anses projekteringsförhĂ„llandena som relativt komplexa, och uppdraget gĂ„r dĂ€rför utanför rutinmĂ€ssig projektering. Examensarbetet har syftat till att utreda tre frĂ„gestĂ€llningar kopplade till referensprojektet; att inventera och utvĂ€rdera möjliga stödkonstruktioner, att identifiera vilka parametrar som Ă€r avgörande vid valet av stödkonstruktion och genom dimensionering och verifiering visa att vald(a) stödkonstruktion(er) Ă€r genomförbar(a). De avgörande faktorerna i valet av stödkonstruktion för referensprojektet identifierades som jordens egenskaper, omgivande miljö, processmetoder, framdrift, praktiska faktorer och storleken för projektet. Efter att ha isolerat konsolsponten som den lĂ€mpligaste stödkonstruktionsmetoden utfördes en ”klassisk” berĂ€kning för att bestĂ€mma vilka krafter och moment som verkar i sponten och dĂ€rmed kunna vĂ€lja erforderlig spontprofil. I detta fall Ă€r schaktdjupet 4 – 5 m och det Ă€r ett grĂ€nsfall om en ren konsolspont kan anvĂ€ndas. Som tumregel brukar anges att sponten ska vara tvĂ„ gĂ„nger sĂ„ djupt installerad i jord under schaktbotten som den Ă€r synlig i schakten. I referensprojektet skulle det innebĂ€ra spontlĂ€ngder pĂ„ upp mot 15 m och dĂ€röver. Det Ă€r sĂ€llan konsolsponter med en lĂ€ngd över 10 m anvĂ€nds, och det har att göra med svĂ„righeten att mobilisera fullt jordtryck mot sponten och de stora rörelser som Ă„tgĂ„r för det. Klassiska handberĂ€kningsmetoder utgĂ„r frĂ„n att fullt utvecklat jordtryck rĂ„der lĂ€ngs hela spontens lĂ€ngd. Detta kan leda till att orimligt höga moment i sponten berĂ€knas. DĂ€rför utfördes motsvarande analys Ă€ven i finita element-programmet PLAXIS för att fĂ„ en mer nyanserad bild av bĂ„de hur systemet spont-jord beter sig och av kraft-, spĂ€nnings- och momentbilden i sponten. I ett finit element-program mobiliseras jordtryck utifrĂ„n de faktiska deformationerna och det kan dĂ„ konstateras att fullt jordtryck inte utvecklas lĂ€ngs hela sponten och att ett betydligt mindre moment berĂ€knas i sponten. En kĂ€nslighetsanalys utfördes ocksĂ„ med PLAXIS. Analyserna i PLAXIS visade att den förvĂ€ntande vattenproblematiken inte utgjorde nĂ„got problem i bĂ„de den ursprungliga berĂ€kningen och i kĂ€nslighetsanalysen. DĂ€remot kunde slutsatsen dras att konsolsponten skulle behöva nĂ„gon form av förstĂ€rkning dĂ„ kĂ€nslighetsanalysen visade att förĂ€ndringar i omgivande geometri och av vattenstĂ„nd innebar en sĂ€kerhetsrisk.In connection with excavations it is common that some kind of retaining construction is needed to prevent failure to occur and also to protect surrounding buildings and infrastructure to be damaged due to deformations in the soil volume. This Thesis has been carried out in conjunction with the engineering firm Reinertsen AB within an actual contract. The assignment is to design a sedimentation basin for drainage water from a nearby tunnel which will be founded about 4 to 5 m below the existing ground surface. Therefore some kind of retaining structure is needed to stabilize the excavation. Within the Thesis work three items have been addressed; identification and evaluation of possible retaining structures, identification of governing factors, and through design and verification show that the chosen structures are possible to use. The most important governing factors were found to be the soil properties, environment aspects, process methods, progress, practical aspects, and the size of the project, respectively. After having identified a classical console sheet pile wall as the most feasible type of retaining structure, first a hand calculation was performed to verify the choice. The length of a console sheet pile should by a rule of thumbs be maximized to about 10 m, of which 2/3 should be installed in soil below the excavation bottom. The reason for this is the difficulties to mobilize full earth pressure against the sheet pile for longer sections. In this case, the sheet pile will have a length of about 15 m, which leads to a very high calculated moment and, thus, unreasonable large sheet pile profiles. Therefore, a finite element analysis was also carried out with the software PLAXIS to get a more nuanced picture of the stresses, forces and moments which develop in the sheet pile. A sensitivity analysis was also done. In this way a more reasonable magnitude of the moment to be developed in the sheet pile was calculated and, thus, a considerably smaller profile could be used

    Experiences of stigma amongst people with substance use disorder : a literature review

    No full text
    Bakgrund: Forskning har visat att stigma gentemot personer relaterat till sÀrskiljande egenskaper leder till försÀmrad hÀlsa för dessa individer. Sedan pionjÀren Erving Goffman 1963 formulerade sin teori om stigma har forskning kring stigma och personer med psykisk ohÀlsa grenat ut sig. Forskning har Àven influerat till att revolutionera förstÄelsen för substansbrukssyndrom, och hur det under det senaste seklet utvecklats frÄn tron att substansbrukssyndrom orsakas av moraliska brister till att det kan ses som en sjukdom som pÄverkar bÄde hjÀrna och beteende. Syfte: Syftet med litteraturstudien var att sammanstÀlla och belysa hur personer med substansbrukssyndrom upplever stigma. Metod: En systematisk kvalitativ litteraturstudie med induktiv ansats inspirerad av Polit och Becks niostegsmodell. Sjutton vetenskapliga artiklar söktes fram systematiskt, sammanstÀlldes och analyserades. Sökningar genomfördes i databaserna PubMed, Cinahl och Taylor & Francis. Resultat: Analysen utmynnade i fem kategorier som beskrev hur personer med substansbrukssyndrom upplevde stigma: att mötas av misstro och att inte bli tagen pÄ allvar, att endast ses för sitt substansbruk och inte som mÀnniska, att fÄ en sÀmre vÄrd Àn andra, att vÄrdpersonalen har negativt bemötande och att beskyllas för sin sjukdom. Slutsats: Att leva med substansbrukssyndrom innebÀr för individen ett dagligt möte med stigma. Litteraturstudiens resultat kan bidra med viktig kunskap om hur patienter med substansbrukssyndrom upplever möten i vÄrden. Detta kan öka kunskap och förstÄelse som i sin tur kan bidra till en förbÀttrad vÄrd för personer med substansbrukssyndrom dÀr lidande för individen minimeras och kostnader för samhÀllet minskas

    Study of active technologies for prefabricated multi-active facade elements for energy renovation of multi-family buildings

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    In Sweden, between 1964 and 1975, approximately one million dwellings were raised in the so called million programme. Due to their age and often neglected maintenance regarding both building envelope and installations, in many cases, comprehensive retrofitting is now required. The aim with this study was to theoretically investigate the energy saving potential and cost-effectiveness of integrating active technologies into a prefabricated insulating façade module, when retrofitting a Swedish case-study high-rise lamella multi-family building from the “Million Program”. The active technologies that were found most suitable in the Swedish context were; centralized supply- and exhaust air ducts with heat recovery where the supply air ducts are routed through the multi-active elements as well as facade integrated photovoltaics. To estimate their energy savings potential, various energy simulations were conducted in software tools such as, HEAT2, IDA ICE and Rhinoceros. To estimate the economic feasibility life cycle calculations were carried out. It was found that the heat losses as well as the annual energy losses from wall integrated ducts were minor even without high performing insulation materials applied. Furthermore, the decrease in the supply air temperate during the coldest hour in the year was acceptable. The results showed that by improving the building envelope and reusing the present exhaust air ducts as well as integrating the supply air ducts in the multi-active element the specific energy use can be lowered by 55 %, from 141 to 62.8 kWh/(mÂČ·yr). The combination of heat recovery from the exhaust air as well as the insulating properties of the multi-active elements are the main contributing factors to the energy savings. The multi-active façade solution with complementary energy saving measures (roof insulation, windows and heat recovery) was found to have a higher saving potential compared to traditionally insulate the building with or without a heat pump. Moreover, the integration of photovoltaic modules in the façade have a restricted potential due to limitations in the Swedish tax regulations. This makes the energy savings of installing photovoltaic modules in the façade roughly covering the investment during the lifetime only when the investment subsidy is awarded. The economic analysis showed that improving the building envelope and implementing a multi-active façade solution, resulted in a competitive alternative in comparison to traditionally insulate the building and as well as to previously documented retrofitting projects in Sweden.A rather new concept used in Europe to energy renovate multi-family buildings is to install prefabricated multi-active wall elements, replacing or placed on the outside of the present exterior walls. These wall elements can include active components such as ventilation ducts and photovoltaics etc., hence the name multi-active. If supply air ventilation ducts are placed in the elements, a supply and exhaust air ventilation system with heat recovery is possible, with the advantage of avoiding major work or disturbance in the apartments. By installing multi-active façade elements a reduction of the energy use by 55 % can be achieved. However, complementary measures such as window change, insulating the roof and installing a mechanical ventilation system with heat recovery are required. A solution like this can also be competitive from an economical point of view compared to traditional renovation approaches
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