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  • 1.
    Ahlström, Elin
    Institutionen för Energi och Teknik, Sveriges lantbruksuniversitet.
    Beräkning av miljömässiga och ekonomiska konsekvenser vid källsortering av blandat byggavfall: samt analys av redovisningsmetoder för byggavfallsstatistik2015Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I en värld där människan är det enda djur som lämnar efter sig avfall som inte kan brytas ned naturligt, är det viktigt att avfallet vi producerar tas om hand på bästa möjliga sätt. EU har därför tagit fram en prioriteringsordning för hur avfallet ska behandlas. Denna kallas avfallshierarkin och ska ligga till grund för medlemsländernas lagstiftning om avfallshantering. I Sverige kallas byggsektorn för den ”40-procentiga sektorn” vilket syftar på att 40 procent av Sveriges avfall genereras av denna sektor. Till år 2020 har EU som målsättning att 70 viktprocent av allt bygg- och rivningsavfall ska återvinnas eller återanvändas. För att presentera säkra siffror som visar ländernas utveckling mot EU:s mål måste avfallsstatistik tas fram på ett bättre sätt än vad som görs i dagsläget.

    Detta examensarbete syftade till att beräkna de miljömässiga och ekonomiska konsekvenserna vid källsortering av blandat byggavfall samt analysera vilken av de tillgängliga metoderna för framtagning av byggavfallsstatistik som är lämpligast.

    En screening av innehållet i det blandade avfallet vid ett renoveringsprojekt hos Telge Bostäder tillsammans med uppgifter om genererad avfallsmängd i ett tidigare genomfört renoveringsprojekt användes för att göra beräkningarna. Den befintliga hanteringen, där avfallet sorterades som blandat avfall, jämfördes sedan med ett hypotetiskt scenario där det vid screeningen identifierade innehållet (plast, trä och wellpapp) istället sorterades ut i separata fraktioner. Beräkningarna gjordes dels i ett av program (WAMPS) framtaget av Svenska miljöinstitutet (IVL) för beräkning av utsläpp från hantering av hushållsavfall och dels med egna beräkningar över koldioxidutsläpp. Kostnaden för att sortera ut avfallet bestämdes genom att använda Sorteras sortiment och prislista.

    Resultatet från WAMPS var att utsläpp av 62 ton koldioxid kunde undvikas från avfallshanteringen genom att sortera ut innehållet i drygt 70 ton blandat byggavfall i separata fraktioner på byggarbetsplatsen. Motsvarande siffra vid egna beräkningar blev 95 ton. Container- och behandlingskostnaden för det sorterade avfallet var lägre än för det osorterade avfallet vilket medförde att den totala avfallskostnaden för drygt 70 ton blandat avfall hade kunnat sänkas med 63 000 kronor om avfallet hade källsorterats.

    Analysen av redovisningsmetoder pekade på att det på kort sikt lämpligaste sättet att ta fram byggavfallsstatistik på, är att använda miljörapporter från avfallsbehandlingsföretagen som underlag för avfallsstatistik. Denna metod kräver ingen lagändring för att genomföras och utnyttjar ett redan befintligt rapporteringssystem.

  • 2.
    Ali, Babar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Study of the performance of the Level-1 track trigger in the H→ττ→ee channel in ATLAS at high luminosity LHC2013Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 3.
    Andersson, Jan O
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Evolution of Patchily Distributed Proteins Shared between Eukaryotes and Prokaryotes: Dictyostelium as a Case Study2011Ingår i: Journal of Molecular Biology and Biotechnology, ISSN 1464-1801, E-ISSN 1660-2412, Vol. 20, nr 2, s. 83-95Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Protein families are often patchily distributed in the tree of life; they are present in distantly related organisms, but absent in more closely related lineages. This could either be the result of lateral gene transfer between ancestors of organisms that encode them, or losses in the lineages that lack them. Here a novel approach is developed to study the evolution of patchily distributed proteins shared between prokaryotes and eukaryotes. Proteins encoded in the genome of cellular slime mold Dictyostelium discoideum and a restricted number of other lineages, including at least one prokaryote, were identified. Analyses of the phylogenetic distribution of 49 such patchily distributed protein families showed conflicts with organismal phylogenies; 25 are shared with the distantly related amoeboflagellate Naegleria (Excavata), whereas only two are present in the more closely related Entamoeba. Most protein families show unexpected topologies in phylogenetic analyses; eukaryotes are polyphyletic in 85% of the trees. These observations suggest that gene transfers have been an important mechanism for the distribution of patchily distributed proteins across all domains of life. Further studies of this exchangeable gene fraction are needed for a better understanding of the origin and evolution of eukaryotic genes and the diversification process of eukaryotes.

  • 4.
    Anderssson, Kristina
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap.
    Hussenius, Anita
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap.
    Gullberg, Annica
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap. Högskolan i Gävle.
    Danielsson, Anna
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Fakulteten för utbildningsvetenskaper, Institutionen för pedagogik, didaktik och utbildningsstudier. Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap.
    Scantlebury, Kathryn
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap. University of Delaware.
    Chafing borderlands: Obstacles for Science Teaching and Learning in Teacher Education2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    A major Western concern is that young people avoid science and technology programs. At various times, and in different countries, governments, funding agencies and businesses have made large investments in recruitment campaigns with the objective to increase students’ interest and attract new groups of students to these disciplines. In particular, girls and women have been the target group for many of these campaigns. The assumption is that if young people understood how exciting and interesting science is, they would choose these subjects. In other words, the problem is that young people "don’t understand what is best for their own good".  In addition, research has shown that primary and pre-school student teachers often feel alienated by science education (Appleton & Kindt 2002) and that it may be difficult for these students to reconcile the role of teacher of young children with the role of science teacher in their identity formation (Danielsson & Warwick 2012).

     

    However, feminist science educators suggest that students’ lack of interest is caused by character and image of the disciplines (Brickhouse 2001; Scantlebury 2012). Feminist philosophers’ of science have challenged the view of natural sciences as objective, and argue that knowledge production is human activities that are socially and culturally situated (Haraway 1988; Harding 1986). A noted problem with science is its elitist image. Science is portrayed as difficult and demanding, and as requiring a special talent from those who study or engage with the discipline. A feminist pedagogical stance is to visualize and discuss cultural, social, and historical dimensions of science. This has also proved advantageous for the acquiring of science content knowledge (Sible et al 2006). Therefore, we argue, that one important aspect of science teacher education is to problematize science (education), e.g. by including feminist critiques of science (Capobianco 2007; Mayberry 1998).

    In this paper we explore the impact of a feminist teaching intervention within teacher education, focusing on the research question: What occurs when students are situated in the encounter between feminist critique of natural sciences and teacher education? What kind of obstacles can be identified and how will these effect pre-service teachers’ pedagogy of science?

     

    The intervention, data collection and analysis

    In an ongoing research and intervention project we are studying how an increased awareness of gender issues in science and in science teaching among student teachers influences their identities as teachers, and their teaching of science. We have followed a cohort of approximately 120 pre-service teachers (early years to lower secondary) from two universities in Sweden, through their first year of science courses. As an integral part of these science courses our intervention has introduced critical perspectives on gender and science as related to the culture of science and a feminist critique of the sciences. The project as a whole is framed theoretically by Hirdman's (1990) and Harding's (1986) theories of gender order in society, where gender is constituted on different levels: the structural, the symbolic and the individual (Harding 1986; Hirdman 1990; Rubin 1975). Hirdman (1990) describes this pattern from two perspectives: first, the separation of the two sexes and second, the superior status of the male standard. The formation of gender consolidates differences between the sexes and the female gender is always subordinate the male one, independent of status, class, time, and space.

  • 5.
    Anderssson, Kristina
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap.
    Hussenius, Anita
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap.
    Scantlebury, Kathryn
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap. University of Delaware.
    Gullberg, Annica
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap.
    Danielsson, Anna
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Fakulteten för utbildningsvetenskaper, Institutionen för pedagogik, didaktik och utbildningsstudier.
    Critiquing science, thinking gender in science teacher education.2014Konferensbidrag (Refereegranskat)
  • 6.
    Balksten, Kristin
    Chalmers.
    Kalkputs: porstrukturens betydelse för beständighet2005Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    When restoring historic lime plaster it can be difficult to reach the required durability. Today newly made lime plaster can fall off due to frost damages after only a couple of winters. To understand and solve these problems, the subject has been studied from different perspectives. Several factors in the production step are making an influence on the durability of lime plaster: 1. A binder, suitable for the building, must be chosen along with sandthat gives good material properties in both fresh mortar and in plasters. 2. The lime/sand ratio and the mixing technique should be chosen from the properties in the lime and the sand, in order to get a mortar with good workability. 3. The craftsmanship should be adjusted to the mortar, the weather and the underlying materials. A plaster with good frost resistance has a certain pore structure. The plaster should have some round air pores that contain air even when the material is filled capillary with water. Such air pores give the water a free space to expand when it is freezing. If the air pores are missing, the ice crystals may damage the plaster when expanding. To increase the chance of making a frost resistant lime plaster, the lime/sand ration must be adjusted so the lime can fill up well in the sand. Otherwise a collapsed pore system can easily occur, which means an open pore system without distinct air pores. A collapsed pore system contains many pores well connected with each other. Such a system is easily damaged by frost. To increase the chance of success, it is of great importance to work the surface of the lime plaster at the right time and in the correct way. Before working on a surface the mortar must be aloud to stiffen. Only then a homogeneous material can be created; cracks due to shrinkage can be pressed together and the result is a more compact material with an open surface. The time necessary for mortars to stiffen is related to the water content of the mortar, the suction of the underlying surface and the weather conditions. If the surface is worked on while the mortar is still fresh, the binder can form a hard lime shell on the surface. Inside thematerial a lack of binder can appear. Such plasters have a very low frost resistance. Other durability problems related to plaster are damages in the underlying materials, i.e. rotten wood in covered constructions or leached lime in old joints. Such damages can occur if the covering mortar is made of strong hydraulic lime or cement, since they form plasters with a low permeability in comparison to lime. Due to mentioned findings, it is important to study how a pore structureis influenced by materials, mixture and craftsmanship. Only then it is possible to understand how damages can be decreased.

    Delarbeten
    1. Permeability in lime plaster in relation to durability of covered materials
    Öppna denna publikation i ny flik eller fönster >>Permeability in lime plaster in relation to durability of covered materials
    2004 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    In restoration of old buildings, lime plasters are used for reasons of authenticity and for technicalreasons as well. In many traditional constructions, there is wood behind the plasters or there is old limemortar in the masonry. For the durability of both these underlying materials, it is important that therelative humidity, RH is not too high under a long time of exposure. This can lead to an accelerateddegradation process of wood and leaching of lime in mortars. To prevent this, the plaster must have aproper permeability.The permeability of a material determines its ability to transport gas and moisture. In lime plasters,permeability affects hardening, carbonation as well as durability of the underlying materials. In thepresent paper, eleven mixtures of lime mortar were studied. The binders used were lime slaked in fourdifferent ways, hydraulic lime and cement.The following measurements were made to analyse the permeability and the pore structure of thesamples. Gas permeability and draining curves give an indication of rate of carbonation. Vapourpermeability shows the ability of plaster to transmit moisture at different RH. Thin sections were madefor microscopically investigations of the samples.The investigations show that both the vapour permeability and gas permeability decreases with anincreased amount of hydraulic binder in the lime plasters. Even small amounts of hydraulic binderhave a significant effect.By connecting these results with examples from reality, the picture becomes clearer. In the medievaltown Visby in Sweden, there are several examples of both rotten wood and disintegrated lime mortars.It is constructions from 13th to 19th centuries and low permeable cementitious plasters have coveredthem all, during the middle of the 20th century.

    Nyckelord
    lime, cement, plaster, pore structure, permeability
    Nationell ämneskategori
    Annan naturvetenskap
    Forskningsämne
    Kulturvård (HGO)
    Identifikatorer
    urn:nbn:se:uu:diva-220075 (URN)
    Konferens
    Proceedings of the 32nd IAHS World Congress on Housing – Sustainability of the Housing Projects. Trento, Italy 2004.
    Forskningsfinansiär
    KK-stiftelsen
    Tillgänglig från: 2014-03-10 Skapad: 2014-03-10 Senast uppdaterad: 2016-01-28
    2. The influence of craftsmanship on the inner structures of lime plasters
    Öppna denna publikation i ny flik eller fönster >>The influence of craftsmanship on the inner structures of lime plasters
    2005 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    The use of traditional lime plaster in restoration of old buildings is motivated by bothtechnical and historic reasons. The plasterer deals daily with a multivariable problem wherethe variables are related in such a complex way that we are not even close to findingconverging solutions by traditional scientific methods. The decisions and actions of thecraftsman will have an influence on both the surface structure and the inner structure of thelime plaster. The present paper will focus on the time between application of mortar andworking on the surface to make a floated finish. In total, 32 lime plaster surfaces have beenanalysed. Half of them have been worked on after they have stiffened up and half of themhave been worked on while they are still fresh. The results clearly show that the time betweenapplication of mortar and working the surface is a critical parameter. If you wait until theright time, you receive a more homogeneous and compact material with an open surface anda higher frost resistance.

    Ort, förlag, år, upplaga, sidor
    Rilem publications, 2005
    Nyckelord
    lime, plaster, pore structure, frost damages, craftsman
    Nationell ämneskategori
    Annan naturvetenskap
    Forskningsämne
    Kulturvård (HGO)
    Identifikatorer
    urn:nbn:se:uu:diva-220077 (URN)
    Konferens
    Proceedings of the International RILEM Workshop Repair Mortars for Historic Masonry. Delft, Holland 2005
    Forskningsfinansiär
    KK-stiftelsen
    Tillgänglig från: 2014-03-10 Skapad: 2014-03-10 Senast uppdaterad: 2014-04-16
    3. The pore structure in lime plaster as a key to understanding moisture transportation properties and frost damages
    Öppna denna publikation i ny flik eller fönster >>The pore structure in lime plaster as a key to understanding moisture transportation properties and frost damages
    2004 (Engelska)Ingår i: 10th International Congress on the Deterioration and Conservation of Stone, 2004Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    The pore structure is of great importance for a materials ability to hold and transport gasand moisture. In lime plaster, it affects hardening, carbonation as well as durability againstfrost damage. In the present paper, eleven mixtures of lime mortar were studied withrespect to frost damages. The binders used were lime slaked in four different ways,hydraulic lime and cement.Several analyses were made to characterize the transport properties and the porestructure of the materials; density, porosity, sorption curves, capillary water suction andthin sections. This study shows that there is a correlation between pore structure andimportant material properties. By studying these parameters, it is possible to get a goodpicture of the materials ability to resist frost damages. The study also gives an indication ofwhat materials in the mortar such as binders, aggregates and water, give a good porestructure.

    Nyckelord
    lime, cement, plaster, mortar, pore structure, building materials, moisture, frost resistance
    Nationell ämneskategori
    Annan naturvetenskap
    Forskningsämne
    Kulturvård (HGO)
    Identifikatorer
    urn:nbn:se:uu:diva-220061 (URN)
    Konferens
    Proceedings of the 10th International Congress on the Deterioration and Conservation of Stone. Stockholm, Sweden 2004
    Forskningsfinansiär
    KK-stiftelsen
    Tillgänglig från: 2014-03-10 Skapad: 2014-03-10 Senast uppdaterad: 2014-04-16
  • 7.
    Balksten, Kristin
    et al.
    Chalmers.
    Broström, Tor
    Högskolan på Gotland, Institutionen för kultur, energi och miljö.
    Permeability in lime plaster in relation to durability of covered materials2004Konferensbidrag (Refereegranskat)
    Abstract [en]

    In restoration of old buildings, lime plasters are used for reasons of authenticity and for technicalreasons as well. In many traditional constructions, there is wood behind the plasters or there is old limemortar in the masonry. For the durability of both these underlying materials, it is important that therelative humidity, RH is not too high under a long time of exposure. This can lead to an accelerateddegradation process of wood and leaching of lime in mortars. To prevent this, the plaster must have aproper permeability.The permeability of a material determines its ability to transport gas and moisture. In lime plasters,permeability affects hardening, carbonation as well as durability of the underlying materials. In thepresent paper, eleven mixtures of lime mortar were studied. The binders used were lime slaked in fourdifferent ways, hydraulic lime and cement.The following measurements were made to analyse the permeability and the pore structure of thesamples. Gas permeability and draining curves give an indication of rate of carbonation. Vapourpermeability shows the ability of plaster to transmit moisture at different RH. Thin sections were madefor microscopically investigations of the samples.The investigations show that both the vapour permeability and gas permeability decreases with anincreased amount of hydraulic binder in the lime plasters. Even small amounts of hydraulic binderhave a significant effect.By connecting these results with examples from reality, the picture becomes clearer. In the medievaltown Visby in Sweden, there are several examples of both rotten wood and disintegrated lime mortars.It is constructions from 13th to 19th centuries and low permeable cementitious plasters have coveredthem all, during the middle of the 20th century.

  • 8.
    Balksten, Kristin
    et al.
    Chalmers.
    Klasén, Kenth
    The influence of craftsmanship on the inner structures of lime plasters2005Konferensbidrag (Refereegranskat)
    Abstract [en]

    The use of traditional lime plaster in restoration of old buildings is motivated by bothtechnical and historic reasons. The plasterer deals daily with a multivariable problem wherethe variables are related in such a complex way that we are not even close to findingconverging solutions by traditional scientific methods. The decisions and actions of thecraftsman will have an influence on both the surface structure and the inner structure of thelime plaster. The present paper will focus on the time between application of mortar andworking on the surface to make a floated finish. In total, 32 lime plaster surfaces have beenanalysed. Half of them have been worked on after they have stiffened up and half of themhave been worked on while they are still fresh. The results clearly show that the time betweenapplication of mortar and working the surface is a critical parameter. If you wait until theright time, you receive a more homogeneous and compact material with an open surface anda higher frost resistance.

  • 9.
    Balksten, Kristin
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Konstvetenskapliga institutionen.
    Lindholm, Martin
    Lange, Johanna
    Increased salt and frost damages in solid neo-Gothic brickwork masonry due to low permeable restoration materials of the 20th century2014Ingår i: 9th IMC, Book of Abstract / [ed] Paulo B. Lourenco, Barry A. Haseltine, Graca Vasconcelos, 2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    In Gothenburg many stone buildings of brickwork were built during the neo-Romanesque and neo-Gothic period in the late 19th century. The masonry was solid with a wall of bricks often covered with facing bricks with a hard burned water repellent surface. At Örgryte new church the bricks were put in lime mortar but the surface of the joints was made with a thin cement mortar layer. Salt problems are known in this church since early 20th century and the subsequent need of maintenance have led to several extensive restorations with replacement of external facing bricks and internal lime plaster during the years. In each restoration more low permeable facing bricks and more low permeable cement mortars have been chosen, followed by new problems inside the wall as the water transport properties in the wall has changed. Whereas salts have caused problems mainly on the surface, the restoration materials have caused problems with frost and salt damages in bricks and lime mortars in the wall core behind them.

  • 10.
    Balksten, Kristin
    et al.
    Chalmers.
    Magnusson, Sophia
    The pore structure in lime plaster as a key to understanding moisture transportation properties and frost damages2004Ingår i: 10th International Congress on the Deterioration and Conservation of Stone, 2004Konferensbidrag (Refereegranskat)
    Abstract [en]

    The pore structure is of great importance for a materials ability to hold and transport gasand moisture. In lime plaster, it affects hardening, carbonation as well as durability againstfrost damage. In the present paper, eleven mixtures of lime mortar were studied withrespect to frost damages. The binders used were lime slaked in four different ways,hydraulic lime and cement.Several analyses were made to characterize the transport properties and the porestructure of the materials; density, porosity, sorption curves, capillary water suction andthin sections. This study shows that there is a correlation between pore structure andimportant material properties. By studying these parameters, it is possible to get a goodpicture of the materials ability to resist frost damages. The study also gives an indication ofwhat materials in the mortar such as binders, aggregates and water, give a good porestructure.

  • 11.
    Balksten, Kristin
    et al.
    Chalmers.
    Myrin, Malin
    Göteborgs Universitet.
    Lime-based Repair Mortars: Influence by Surface Working Methods onBehaviour and Durability of Mortar2006Konferensbidrag (Refereegranskat)
    Abstract [en]

    The main purpose of this study was to observe the influence by different surface working methodson behaviour, durability and appearance of lime-based stone-repair mortars.The findings are based on:

    - Observations made during restoration work

    - Observations from field stations

    - Microscopic analysis of thin sections of mortar

    - Parallel studies on lime plaster

    The results show clear differences in durability, appearance and behaviour of lime-based mortar dependingon at which stage of the drying process the mortar is worked on. For achieving durable mortar it is importantto avoid the development of a surface lime-film. The study implies that the mortar, only when worked on at aspecific stage of drying, will be durable and have a structure, texture and porosity compatible with the surroundingstone material.

  • 12.
    Balksten, Kristin
    et al.
    Department of Chemical and Biological Engineering, Environmental Inorganic Chemistry, Chalmers University of Technology.
    Steenari, Britt-Marie
    Department of Chemical and Biological Engineering, Environmental Inorganic Chemistry, Chalmers University of Technology.
    A method to recreate historic mortars applied at Norr­landa church on the island of Gotland, Sweden2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this work, scanning electron microscopy analysis of lime slaked in different ways and analysis of thin section limeputty and mortar specimens by light microscopy was combined with practical tests and field studies in order to evaluatethe impact of the slaking technique on the properties of the lime putty, and also the structure of the fresh and carbonatedmortar. The lime slaking methods studied were wet slaking and earth slaking. These techniques give lime putties withvery different consistency and workability. The aim of this work was to use microscopy techniques to explain thesedifferences in properties and to investigate if it is possible to use these analytical methods to recognize the lime slakingtechnique used in a historical lime mortar.The results obtained by electron microscopy show significant differences in structure between the lime puttiesstudied. The earth slaked lime consists of relatively large particles that are packed in a porous system as compared to thewet slaked lime with very small particles closely packed in a dense structure. After storing, the wet slaked lime gives aputty, that has a dense and clearly defined stratified structure, whereas the earth slaked lime is porous and has nostratification. The earth slaked lime is tixotropic and has a light, smooth consistency reminding of well whipped creamcompared to the wet slaked lime that has a strong orientation and a rather stiff consistency reminding more of pudding.Microscopy investigations of thin section mortar specimens showed how the lime affects the mortar concerninghomogeneity, density, pore structure and crack patterns.

  • 13. Bisol, Giovanni Destro
    et al.
    Anagnostou, Paolo
    Capocasa, Marco
    Bencivelli, Silvia
    Cerroni, Andrea
    Contreras, Jorge
    Enke, Neela
    Fantini, Bernardino
    Greco, Pietro
    Heeney, Catherine
    Luzi, Daniela
    Manghi, Paolo
    Mascalzoni, Deborah
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för folkhälso- och vårdvetenskap, Centrum för forsknings- och bioetik.
    Molloy, Jennifer C.
    Parenti, Fabio
    Wicherts, Jelte M.
    Boulton, Geoffrey
    Perspectives on Open Science and scientific data sharing: an interdisciplinary workshop2014Ingår i: J ANTHROPOL SCI, ISSN 1827-4765, Vol. 92, s. 179-200Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Looking at Open Science and Open Data from a broad perspective. This is the idea behind "Scientific data sharing: an interdisciplinary workshop", an initiative designed to foster dialogue between scholars from different scientific domains which was organized by the Istituto Italiano di Antropologia in Anagni, Italy, 2-4 September 2013. We here report summaries of the presentations and discussions at the meeting. They deal with four sets of issues: (i) setting a common framework, a general discussion of open data principles, values and opportunities; (ii) insights into scientific practices, a view of the way in which the open data movement is developing in a variety of scientific domains (biology, psychology, epidemiology and archaeology); (iii) a case study of human genomics, which was a trail-blazer in data sharing, and which encapsulates the tension that can occur between large-scale data sharing and one of the boundaries of openness, the protection of individual data; (iv) open science and the public, based on a round table discussion about the public communication of science and the societal implications of open science. There were three proposals for the planning of further interdisciplinary initiatives on open science. Firstly, there is a need to integrate top-down initiatives by governments, institutions and journals with bottom-up approaches from the scientific community. Secondly, more should be done to popularize the societal benefits of open science, not only in providing the evidence needed by citizens to draw their own conclusions on scientific issues that are of concern to them, but also explaining the direct benefits of data sharing in areas such as the control of infectious disease. Finally, introducing arguments from social sciences and humanities in the educational dissemination of open data may help students become more profoundly engaged with Open Science and look at science from a broader perspective.

  • 14.
    Blicharska, Malgorzata
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences.
    Scale of global road map is impractical2013Ingår i: Nature, Vol. 496, nr 7445, s. 300-300Artikel i tidskrift (Övrigt vetenskapligt)
  • 15.
    Blicharska, Malgorzata
    et al.
    School for Forest Management, Swedish University of Agricultural Sciences.
    Angelstam, Per
    School for Forest Management, Swedish University of Agricultural Sciences.
    Conservation at risk: conflict analysis in the Białowieża Forest, a European biodiversity hotspot2010Ingår i: International Journal of Biodiversity Science, Ecosystem Services & Management, ISSN 2151-3732, E-ISSN 2151-3740, Vol. 6, nr 1, s. 68-74Artikel i tidskrift (Refereegranskat)
  • 16.
    Blicharska, Malgorzata
    et al.
    School for Forest Management, Swedish University of Agricultural Sciences.
    Angelstam, Per
    Swedish Univ Agr Sci, Sch Forest Management, Fac Forest Sci, Skinnskatteberg, Sweden.
    Antonson, Hans
    VTI Swedish Natl Rd & Transport Res Inst, SE-58195 Linkoping, Sweden.
    Elbakidze, Marine
    Swedish Univ Agr Sci, Sch Forest Management, Fac Forest Sci, Skinnskatteberg, Sweden.
    Axelsson, Robert
    Swedish Univ Agr Sci, Sch Forest Management, Fac Forest Sci, Skinnskatteberg, Sweden.
    Road, forestry and regional planners’ work for biodiversity conservation and public participation: a case study in Poland’s hotspots regions2011Ingår i: Journal of Environmental Planning and Management, ISSN 0964-0568, E-ISSN 1360-0559, Vol. 54, nr 10, s. 1373-1395Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We studied how regional, road and forestry planning sectors work to implement policies about biodiversity conservation and public participation. Evaluations were based on a normative model for planning derived from the existing international policies and relevant literature. Key planning actors were then interviewed with regard to their understanding of biodiversity and participation policies as well as ability to act and willingness to implement them. The results indicate several gaps in planning processes, for example, insufficient knowledge about biodiversity conservation and participation, limited resources and tools for planning of functional habitat networks and collaboration, poor connections between local and regional planning, and weakly developed public participation. The main problem for effective policy implementation seems to be related to planners' ability to act, which indicates that relatively low priority was given to provide resources for biodiversity conservation and public participation by the relevant units. We discuss our findings in relation to the implementation of environmental policies in the new EU countries of Eastern and Central Europe.

  • 17.
    Blicharska, Malgorzata
    et al.
    School for Forest Management, Swedish University of Agricultural Sciences.
    Angelstam, Per
    School for Forest Management, Swedish University of Agricultural Sciences.
    Elbakidze, Marine
    School for Forest Management, Swedish University of Agricultural Sciences.
    Axelsson, Robert
    School for Forest Management, Swedish University of Agricultural Sciences.
    Skorupski, Maciej
    Poznan University of Life Sciences, Faculty of Forestry.
    Wegiel, Andrzej
    Poznan University of Life Sciences, Faculty of Forestry.
    The Polish Promotional Forest Complex: objectives, implementation and outcomes towards sustainable forest management?2012Ingår i: Forest Policy and Economics, ISSN 1389-9341, E-ISSN 1872-7050, Vol. 23, s. 28-39Artikel i tidskrift (Refereegranskat)
  • 18.
    Blicharska, Malgorzata
    et al.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences.
    Baxter, Peter
    Mikusinski, Grzegorz
    School for Forest Management, Swedish University of Agricultural Sciences.
    Practical implementation of species’ recovery plans – lessons from the White-backed Woodpecker Action Plan in Sweden.2014Ingår i: Ornis Fennica, ISSN 0030-5685, Vol. 91, s. 108-128Artikel i tidskrift (Refereegranskat)
  • 19.
    Blicharska, Malgorzata
    et al.
    Department of Auqatic Sciences and Assessment, Swedish University of Agricultural Sciences.
    Mikusinski, Grzegorz
    School for Forest Management, Swedish University of Agricultural Sciences.
    Metrics: a long-term threat to society2012Ingår i: Nature, Vol. 490, nr 7420, s. 343-343Artikel i tidskrift (Övrigt vetenskapligt)
  • 20.
    Blicharska, Malgorzata
    et al.
    Department of Auqatic Sciences and Assessment, Swedish University of Agricultural Sciences.
    Mikusinski, Grzegorz
    School for Forest Management, Swedish University of Agricultural Sciences.
    Old trees: cultural value.2013Ingår i: Science, Vol. 339, s. 904-Artikel i tidskrift (Övrigt vetenskapligt)
  • 21.
    Blicharska, Malgorzata
    et al.
    School for Forest Management, Swedish University of Agricultural Sciences.
    Mikusinski, Grzegorz
    School for Forest Management, Swedish University of Agricultural Sciences.
    Think bigger for conservation2011Ingår i: Nature, Vol. 470, nr 7332, s. 39-39Artikel i tidskrift (Övrigt vetenskapligt)
  • 22.
    Blicharska, Malgorzata
    et al.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences.
    Mikusinski, Grzegorz
    School for Forest Management, Swedish University of Agricultural Sciences.
    Godbole, Archana
    Safeguarding biodiversity and ecosystem services of sacred groves – experiences from northern Western Ghats.2013Ingår i: International Journal of Biodiversity Science, Ecosystem Services & Management, ISSN 2151-3732, E-ISSN 2151-3740, Vol. 9, nr 4, s. 339-346Artikel i tidskrift (Refereegranskat)
  • 23.
    Boberg, Camilla
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Biodiversity and EcosystemServices in Monquentiva, Colombia – a case study of conservation: 2012Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In the Eastern Andean mountain range in Colombia there is an ongoing project with the aim of preserving important conservation values such as water resources and biodiversity. In the light of climate change and increased land use there is a pressing need of managing remaining natural habitats and the services they provide in the Colombian Andes. As part of a conservation corridor around the city of Bogotá, the proposed protected area of Monquentiva could increase the connectivity and resilience of the remaining ecosystems in the area. The Millennium Ecosystem Assessment states the importance of ecosystems and biodiversity for the provisioning of ecosystem services and as a prerequisite for human wellbeing. From a sustainable development point of view the assessment was used as a basis for a paradigm analysis of conservation values. The main question of the paper is how the protection of an area can incorporate both biodiversity and ecosystem services at the lowest cost possible. The conclusion is that a combination of biodiversity and ecosystem services for more cost efficient conservation strategies is desired. It could bring an increased focus on economical benefits and increase the willingness of decision makers to increase protection of important areas. Intrinsic value and cultural services could be complementing for conservation implementation. For the area of Monquentiva, the willingness of the landowners to participate and contribute with available means seem promising for future ecosystem management.

  • 24.
    Bondeson, Anna
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Grönlund, Sanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Opportunities and challenges in the management of an innovation laboratory: A case study of Semcon Innovation Lab2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Innovation laboratories are environments especially designed for carrying out the innovation process. They are an example of a new kind of organisational structure that has emerged as a managerial response to challenges associated with organisational dynamic capability development. Using a mixed-method approach, this thesis attempts to create an understanding for the challenges and opportunities that exist in the management of an innovation laboratory, both on a level of organisational innovation and of individual creativity. The componential model of creativity and innovation in organisations is used as a framework for analysis of an innovation laboratory in the case company, the tech consultancy firm Semcon.

    The results confirm that there is a lack of clarity in the conceptualisation of innovation labs. Some important findings are that the implementation of an innovation laboratory could in itself be seen as an opportunity, but that acting in the borderland between the objectives of profitability and creativity could prove a challenge. A challenge may also lie in maintaining a realistic view of the actual abilities of the innovation laboratory. Cross-functional collaboration between consultants seems to bring opportunities in that it may contribute to knowledge creation and transfer within the firm, but there is a challenge in that teams are in need of leaders with skills in creativity management and agile project management, but also technical expertise. A general conclusion for managing innovation laboratories is that they need enough resources to have room for mistakes. The findings have implications for the management of existing innovation laboratories and those in the planning.

  • 25.
    Bottinelli, Arianna
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen, Tillämpad matematik och statistik.
    van Wilgenburg, E.
    Fordham Univ, Dept Biol Sci, Bronx, NY 10458 USA..
    Sumpter, David J. T.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen, Tillämpad matematik och statistik.
    Latty, T.
    Univ Sydney, Sch Biol Sci, Sydney, NSW 2006, Australia..
    Local cost minimization in ant transport networks: from small-scale data to large-scale trade-offs2015Ingår i: Journal of the Royal Society Interface, ISSN 1742-5689, E-ISSN 1742-5662, Vol. 12, nr 112, artikel-id 20150780Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Transport networks distribute resources and information in many human and biological systems. Their construction requires optimization and balance of conflicting criteria such as robustness against disruptions, transport efficiency and building cost. The colonies of the polydomous Australian meat ant Iridomyrmex purpureus are a striking example of such a decentralized network, consisting of trails that connect spatially separated nests. Here we study the rules that underlie network construction in these ants. We find that a simple model of network growth, which we call the minimum linking model (MLM), is sufficient to explain the growth of real ant colonies. For larger networks, the MLM shows a qualitative similarity with a Euclidean minimum spanning tree, prioritizing cost and efficiency over robustness. We introduce a variant of our model to show that a balance between cost, efficiency and robustness can be also reproduced at larger scales than ant colonies. Remarkably, such a balance is influenced by a parameter reflecting the specific features of the modelled transport system. The extended MLM could thus be a suitable source of inspiration for the construction of cheap and efficient transport networks with non-zero robustness, suggesting possible applications in the design of human-made networks.

  • 26.
    Buratovic, Sonja
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Miljötoxikologi.
    Stenerlöw, Bo
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Medicinsk strålningsvetenskap.
    Fredriksson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Miljötoxikologi.
    Sundell-Bergman, Synnöve
    Sveriges lantbruksuniversitet, Fakulteten för naturresurser och lantbruksvetenskap, Institutionen för Mark och miljö.
    Viberg, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Miljötoxikologi.
    Eriksson, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Miljötoxikologi.
    Neonatal exposure to a moderate dose of ionizing radiation causes behavioural defects and altered levels of tau protein in mice2014Ingår i: Neurotoxicology, ISSN 0161-813X, E-ISSN 1872-9711, Vol. 45, s. 48-55Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Medical use of ionizing radiation (IR) has great benefits for treatment and diagnostic imaging, butprocedures as computerized tomography (CT) may deliver a significant radiation dose to the patient.Recently, awareness has been raised about possible non-cancer consequences from low dose exposure toIR during critical phases of perinatal and/or neonatal brain development.In the present study neonatal NMRI mice were whole body irradiated with a single dose of gammaradiation (0; 350 and 500 mGy) on postnatal day 10 (PND 10). At 2 and 4 months of age, mice of bothsexes were observed for spontaneous behaviour in a novel home environment. The neuroproteinsCaMKII, GAP-43, synaptophysin and total tau in male mouse cerebral cortex and hippocampus wereanalysed 24 h post-irradiation and in adults at 6 months of age exposed to 0 or 500 mGy on PND 10.A significantly dose-response related deranged spontaneous behaviour in 2- and 4-month-old micewas observed, where both males and females displayed a modified habituation, indicating reducedcognitive function. The dose of 350 mGy seems to be a tentative threshold. Six-month-old male miceshowed a significantly increased level of total tau in cerebral cortex after irradiation to 500 mGy compared to controls. This demonstrates that a single moderate dose of IR, given during a defined criticalperiod of brain development, is sufficient to cause persistently reduced cognitive function. Moreover, anelevation of tau protein was observed in male mice displaying reduced cognitive function.

  • 27.
    Bylund Melin, Charlotta
    et al.
    Göteborgs universitet.
    Legnér, Mattias
    Högskolan på Gotland, Institutionen för kultur, energi och miljö. Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Konstvetenskapliga institutionen. Uppsala universitet.
    The relationship between heating energy and cumulative damage to painted wood in historic churches2014Ingår i: Journal of the Institute of Conservation, nr 3, s. 94-109Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Existing research on climate-induced damage needs to be verified by actual observations in authentic environments. This article suggests a complementary method to relate the historic and present indoor climate to damage on painted wooden objects in historic churches. Energy consumption, as revealed by archival sources, is used as a substitute for climate records, on the assumption that higher temperature and therefore lower relative humidity will occur more frequently in churches with greater expenses for fuel. The quantified energy consumption is related to damage of wood and the painted layers of pulpits in 16 churches. There is a slight correlation between damage to the paint on the pulpits and energy released in the churches. However larger populations are needed for this type of enquiry to be further developed and extended. 

  • 28.
    Bylund Melin, Charlotte
    et al.
    Göteborg University.
    Legnér, Mattias
    Högskolan på Gotland, Institutionen för kultur, energi och miljö.
    Quantification, the link to relate climate-induced damage to indoor environments in historic buildings2013Ingår i: Climate for collections: Standards and uncertainties: Postprints of the Munich Climate Conference 7 to 9 November 2012 / [ed] Jonathan Ashley-Smith, Andreas Burmester and Melanie Eibl, 2013, s. 311-323Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper describes and applies a method to quantify and related damage of painted wooden pulpits in 16 churches in Gotland, Sweden, to both the current and the historical indoor climate of the twentieth century. In addition, it demonstrates that the energy used to heat a church in the past can be measured and the study alsopoints towards a relationship between damage and heat output. The results suggest that more damage is present in churches with a higher heat output and there is increased damage in churches using background heating compared to churches that do not. However, the method needs to be improved and a larger population is required to validate these results.

  • 29.
    Carter, Megan
    et al.
    Stockholms universitet, Institutionen för biokemi och biofysik.
    Jemth, Ann-Sofie
    Hagenkort, Anna
    Page, Brent D. G.
    Gustafsson, Robert
    Stockholms universitet, Institutionen för biokemi och biofysik.
    Griese, Julia J.
    Stockholms universitet, Institutionen för biokemi och biofysik.
    Gad, Helge
    Valerie, Nicholas C. K.
    Desroses, Matthieu
    Boström, Johan
    Berglund, Ulrika Warpman
    Helleday, Thomas
    Stenmark, Pål
    Stockholms universitet, Institutionen för biokemi och biofysik.
    Crystal structure, biochemical and cellular activities demonstrate separate functions of MTH1 and MTH22015Ingår i: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 6, artikel-id 7871Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Deregulated redox metabolism in cancer leads to oxidative damage to cellular components including deoxyribonucleoside triphosphates (dNTPs). Targeting dNTP pool sanitizing enzymes, such as MTH1, is a highly promising anticancer strategy. The MTH2 protein, known as NUDT15, is described as the second human homologue of bacterial MutT with 8-oxo-dGTPase activity. We present the first NUDT15 crystal structure and demonstrate that NUDT15 prefers other nucleotide substrates over 8-oxo-dGTP. Key structural features are identified that explain different substrate preferences for NUDT15 and MTH1. We find that depletion of NUDT15 has no effect on incorporation of 8-oxo-dGTP into DNA and does not impact cancer cell survival in cell lines tested. NUDT17 and NUDT18 were also profiled and found to have far less activity than MTH1 against oxidized nucleotides. We show that NUDT15 is not a biologically relevant 8-oxo-dGTPase, and that MTH1 is the most prominent sanitizer of the cellular dNTP pool known to date.

  • 30.
    Chidiac, Joseph
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Effects of chemical exposure on the reproductive ability of Xenopus tropicalis2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    During the last decades the amphibian population has been greatly reduced. In many cases the reasons for this reduction is unknown but contamination of the living environment of amphibians may be one of the causing factors. Environmental contamination has been shown to interfere with the functions of the amphibian endocrine system, lead to reduced fertility and overall reproductive disorder. The aim of this study is to investigate the effects of an herbicide and pharmaceutical drug on the reproductive ability in the amphibian Xenopus tropicalis.

    Four exposure groups of frogs were mated with unexposed frogs. The number of fertilized eggs was scored by image analysis.

    The study revealed that the frogs given the low dose of the herbicide as well as the pharmaceutical drug had a reduced fertility rate compared to the negative control. Very few studies have been made that look into the long-term effects of environmental contaminant exposure of amphibians. These studies are important for the future health of the amphibian population. 

  • 31.
    Chizarifard, Azadeh
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Statistiska institutionen.
    SEM Analysis of Epigenetic Data2014Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 32.
    Claesson, Elin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Luft-, vatten och landskapslära.
    Identifiering och utvärdering av växters bullerreducerande förmåga i urban miljö2015Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Trafikbuller är den miljöstörning som påverkar flest människor i Sverige. Studier visar att buller kan påverka människors hälsa genom att orsaka hörselskador, stress, sömnsvårigheter och i förlängningen hjärt- och kärlsjukdomar. Idag byggs städerna i Sverige allt tätare, vilket gör att antalet bullerstörda personer fortsätter att öka. För att dämpa buller används ofta höga och breda bullerskärmar, vilket inte är att föredra i urban miljö. Ny forskning undersöker därför andra alternativ, bland annat hur växter och gröna områden kan verka bullerreducerande. Forskare menar att växter med hjälp av sina stammar, bladverk och substratet de står i kan reducera ljud genom reflektion, absorption och spridning av ljudenergin.

    Detta examensarbete syftade till att utvärdera olika växtelement ur bullerreducerande synpunkt. Växters bullerreducerande förmåga är något varken akustiker eller landskapsarkitekter generellt sett tar hänsyn till och därför ansågs en kunskapssammanställning ligga i tiden. För att göra detta har en litteraturstudie, två intervjuer samt mätningar på två växtelement utförts. Mätningarna gjordes på häckar längs Luthagsesplanaden i Uppsala och på en fasad med klätterväxter på Norr Mälarstrand i Stockholm.

    Litteratur- och intervjustudien visade att växtbeklädda bullerbarriärer hade högst potential att reducera buller längs vägar, gröna tak högst potential att reducera buller in på innergårdar och gröna fasader högst potential att dämpa buller på torg. Växter har också möjlighet att osynliggöra ljudkällor, vilket gör att vi upplever ljudet som lägre.

    Mätningarna visade att häcken på Luthagsesplanaden hade möjlighet att dämpa ljudet precis bakom häcken med upp till 3 decibel (dBA). Minskningen höll sig inte ända in till fasaden vilket tros bero på att det reflekterade ljudet dominerar i gaturummet samt att den avskärmande effekten minskar med ökat avstånd. Höga frekvenser dämpades bäst av häcken med den högsta dämpningen på 18 dBA för frekvensbandet 16000 Hz. Dämpningen av de höga frekvenserna syns även in vid fasaden med en dämpning kring 4-5 dBA. Häcken efterliknades i modelleringsprogrammet CadnaA med den nordiska beräkningsmodellen för vägtrafikbuller, men inget objekt tycktes kunna representera häcken på ett reproducerbart sätt.

    På Norr Mälarstrand visades ingen signifikant skillnad i varken ljudtrycksnivå eller frekvensfördelning från fasaden med klätterväxter. En dämpning på upp till 4 dBA för frekvenser över 800 Hz kan dock antydas in vid fasaden. Vid modellering av fasaden visades att varken en reflekterande eller en absorberande fasad kunde representera klätterväxterna.

  • 33.
    den Boer, Wendy
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Locomotory Evolution in Macropodiforms (Kangaroos and Rat-kangaroos)2016Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
  • 34.
    Edfors, Inger
    et al.
    Department of Chemistry and Biomedicine, Linnaeus University.
    Wikman, Susanne
    Department of Chemistry and Biomedicine, Linnaeus University.
    Johansson Cederblad, Brita
    Department of Biology and the Environment, Linnaeus University.
    Linder, Cedric
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Fysikundervisningens didaktik.
    University students' reflections on representations in genetics and stereochemistry revealed by a focus group approach2015Ingår i: NorDiNa: Nordic Studies in Science Education, ISSN 1504-4556, E-ISSN 1894-1257, Vol. 11, nr 2, s. 169-179Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Genetics and organic chemistry are areas of science that students regard as difficult to learn. Part of this difficulty is derived from the disciplines having representations as part of their discourses. In order to optimally support students’ meaning-making, teachers need to use representations to structure the meaning-making experience in thoughtful ways that consider the variation in students’ prior know-ledge. Using a focus group setting, we explored 43 university students’ reasoning on representations in introductory chemistry and genetics courses. Our analysis of eight focus group discussions revealed how students can construct somewhat bewildered relations with disciplinary-specific representa-tions. The students stated that they preferred familiar representations, but without asserting the meaning-making affordances of those representations. Also, the students were highly aware of the affordances of certain representations, but nonetheless chose not to use those representations in their problem solving. We suggest that an effective representation is one that, to some degree, is familiar to the students, but at the same time is challenging and not too closely related to “the usual one”. The focus group discussions led the students to become more aware of their own and others ways of interpreting different representations. Furthermore, feedback from the students’ focus group discus-sions enhanced the teachers’ awareness of the students’ prior knowledge and limitations in students’ representational literacy. Consequently, we posit that a focus group setting can be used in a university context to promote both student meaning-making and teacher professional development in a fruitful way.

  • 35. Eriksson, Anders
    et al.
    Williams, Michael
    Yamskova, Olga
    Cerda-Reverter, José
    Schiöth, Helgi
    Nutrition regulates conserved obesity-linked genes in mouse, zebrafish and fruit flyManuskript (preprint) (Övrigt vetenskapligt)
  • 36.
    Evans, Simon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Sports doping vastly underestimated2015Ingår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 519, nr 7541, s. 33-33Artikel i tidskrift (Refereegranskat)
  • 37. EWALD, G
    et al.
    SUNDIN, Peter
    ATP LEAKAGE FROM ELD CELLS AFTER EXPOSURE TO STEARIC, MONOCHLOROSTEARIC, DICHLOROSTEARIC, AND OLEIC ACIDS1993Ingår i: Pharmacology and Toxicology, ISSN 0901-9928, E-ISSN 1600-0773, Vol. 73, nr 3, s. 159-162Artikel i tidskrift (Refereegranskat)
  • 38. Ewald, G
    et al.
    Sundin, Peter
    Skramstad, J
    Froyen, P
    Distribution of C-14 from ingested, radiolabelled dichlorostearic, stearic and oleic acids in body and in lipids of perch, Perca fluviatilis1996Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 36, nr 1-2, s. 129-139Artikel i tidskrift (Refereegranskat)
  • 39.
    Forngren, Sofia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för biologisk grundutbildning. Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Fakulteten för utbildningsvetenskaper, Institutionen för pedagogik, didaktik och utbildningsstudier.
    Kognitiv neurovetenskap i skolan2019Självständigt arbete på avancerad nivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Utvecklingen av nya metoder för att studera hjärnans struktur och funktion har lett till ny förståelse om kognition. Inom kognitiv neurovetenskap studeras sambandet mellan hjärnan och tänkandet, där inlärning ingår. Hur inlärning fungerar är väsentligt för att utbildning tillgodogörs. Denna litteraturstudie är baserad på delar av den kognitiva neurovetenskapen som berör olika aspekter av vad skolan och lärare kan ha nytta av för att främja elevers inlärning. Hjärnans olika funktioner kan ofta kopplas till olika regioner i hjärnan, och hippocampus samt främre hjärnbarken är två viktiga regioner för både minnesbildning samt framplockning av minnen. Främre hjärnbarken är dessutom den del av hjärnan där de exekutiva funktionerna som har stor betydelse för inlärning är lokaliserade. En viktig förutsättning för inlärning är att hjärnan är plastisk, den kan förändras både strukturellt och biokemiskt. Hjärnan är plastisk hela livet, men fram tills 25-årsåldern då hjärnan fortfarande utvecklas sker större förändringar, vilket har betydelse för såväl inlärning som beteende. Stress kan genom bland annat synaptisk plasticitet påverka inlärning på ett negativt sätt över tid, samtidigt som det även direkt hämmar vår förmåga både att lära oss och att minnas. Till exempel kan stress hämma våra exekutiva funktioner, varav arbetsminnet är en sådan funktion som är betydande för inlärning. Många ungdomar idag lider av psykisk ohälsa, och upplevelser av negativa emotioner bidrar till att hjärnan och kroppen upplever stress. För att öka elevers uppmärksamhet är det därför viktigt med ett klassrum där det är lugnt och alla känner sig trygga. Elevers uppmärksamhet och inlärning kan även påverkas genom motivation, som i hjärnan är lokaliserat i en del av belöningssystemet. Det är även förmågan att lära sig genom återkoppling, som är ett effektivt sätt att skapa inlärning. Hjärnan lär sig genom att associera ny information till tidigare lagrad kunskap, vilket är bra att tänka på framförallt när ny kunskap ska presenteras. Bra sömn och fysisk aktivitet är två faktorer som är viktiga för minnesbildningen men som kan kännas svåra att påverka som lärare, samtidigt som det inte är helt omöjligt. Även mindfulness kan implementeras och bidra till både bättre välmående och inlärning. Den kognitiva neurovetenskapen kan på flera sätt tillämpas i skolan för att främja elevers inlärning.

  • 40.
    Grandell, Leena
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Globala energisystem.
    Hall, Charles
    State University of New York.
    Höök, Mikael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Globala energisystem.
    Energy Return on Investment for Norwegian Oil and Gas from 1991 to 20082011Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 3, nr 11, s. 2050-2070Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Norwegian oil and gas fields are relatively new and of high quality, which has led, during recent decades, to very high profitability both financially and in terms of energy production. One useful measure for profitability is Energy Return on Investment, EROI. Our analysis shows that EROI for Norwegian petroleum production ranged from 44:1 in the early 1990s to a maximum of 59:1 in 1996, to about 40:1 in the latter half of the last decade. To compare globally, only very few, if any, resources show such favorable EROI values as those found in the Norwegian oil and gas sector. However, the declining trend in recent years is most likely due to ageing of the fields whereas varying drilling intensity might have a smaller impact on the net energy gain of the fields. We expect the EROI of Norwegian oil and gas production to deteriorate further as the fields become older. More energy-intensive production techniques will gain in importance.

  • 41.
    Gullberg, Annica
    et al.
    Högskolan i Gävle.
    Anderssson, Kristina
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap.
    Hussenius, Anita
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap.
    Danielsson, Anna
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Fakulteten för utbildningsvetenskaper, Institutionen för pedagogik, didaktik och utbildningsstudier. Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap.
    Scantlebury, Kathryn
    University of Delaware.
    Can the Ambition with Individualize Pedagogy Limit the Children in Pre-school?2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    At two Swedish universities critical perspectives on gender and science were integrated as part of preschool teacher science courses. In one assignment 45 preservice teachers described and reflected upon episodes in their pre-school placements where they judged gender to be of importance and impacted the children’s science and technology learning. Two main themes regarding the view of children were identified: (1) children have a stable core identity and should be supported to ‘be who they are’, or (2) children are a “jack-of-all-trades” with potential interests in a variety of subject matter topics and that these interests could be supported by teachers.  We will discuss how the different themes may affect preservice teachers’ strategies to challenge children’s stereotypical gender patterns.

  • 42. Gustafson-Svard, C
    et al.
    Akesson-Nilsson, G
    Mattsson, M
    Sundin, Peter
    Wesen, C
    Removal of xenobiotic dichalorostearic acid from phospholipids and neutral lipids in cultured human cell lines by beta-oxidation and secretion of dichloromyristic acid2001Ingår i: Pharmacology and Toxicology, ISSN 0901-9928, E-ISSN 1600-0773, Vol. 89, nr 1, s. 56-64Artikel i tidskrift (Refereegranskat)
  • 43.
    Halldin, Krister
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för fysiologi och utvecklingsbiologi, Ekotoxikologi.
    Berg, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för fysiologi och utvecklingsbiologi, Ekotoxikologi.
    Bergman, Åke
    Brandt, Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för fysiologi och utvecklingsbiologi, Ekotoxikologi.
    Brunström, Björn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för fysiologi och utvecklingsbiologi, Ekotoxikologi.
    Distribution of bisphenol A and tetrabromobisphenol A in quail eggs, embryos and laying birds and studies on reproduction variables in adults following in ovo exposure2001Ingår i: ARCHIVES OF TOXICOLOGY, ISSN 0340-5761, Vol. 75, nr 10, s. 597-603Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In a previous study, we showed that bisphenol A (BPA) had oestrogen-like effects in bird embryos, causing malformations of the oviducts in Japanese quail (Coturnix japonica) and feminisation of the left testis in chicken (Gallus domesticus). In this study

  • 44. Harrison, Paula
    et al.
    Berry, Pam
    Simpson, G
    Blicharska, Malgorzata
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences.
    Brandweiner, U
    et, al.
    Linkages between biodiversity attributes and ecosystem services: a systematic review2014Ingår i: Ecosystem Services, ISSN 2212-0416, E-ISSN 2212-0416, Vol. 9, s. 191-203Artikel i tidskrift (Refereegranskat)
  • 45.
    Hassan, Simon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Hur kommer införandet av GDPR, givet den framtida elmarknadshubben påverka energibolagen?: En fallstudie på energibolaget Sala-Heby Energi AB2018Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The storage of data has grown exponentially the last couple of years and the discussion about the personal integrity is a controversial topic at the moment. The data contains personal information and a large proportion of the data is to a greater extent available to the public. Because of these high risks of lacking personal information, EU has decided to establish a new directive that is called the general data protection regulation (GDPR).

    The Energy Market Inspectorate (Ei) is a Swedish state administrative authority that has developed a proposal for a new market model for the energy industry. The model is based on a electricity market hub which will gather all the data. This new model will also raise the competetion in the energy market. The hub is scheduled to be implemented in 2021 and until then, energy companies in Sweden need to analyze what internal changes that needs to be done to have the right prerequisites.

    Many organizations have major problems with change processes and the main reason is that the companies do not spend enough time and commitment on factors such as norms and values amoung employees.

    This is a case study where I have studied what qualifications and obstacles the energy company Sala-Heby Energi possess in order to meet the new challenges regarding GDPR and the new market model. I have through interviews and internal analyzes concluded that there are number of qualifications needed to meet the new data protection regulation and the new market model for the energy industry. I also concluded that a lot more responsibility will be required in the organisation when it comes to processing ofpersonal data. Furthermore, Sala-Heby Energy underwent a change process that was very similar to a model called the 8-step model of change by Kotter (1996). Finally, this study shows that there is no clear analysis of Ei on how the new data protection regulation will affect the electricity market hub.

  • 46.
    Henriksson, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Astronomiska observatoriet.
    Old Uppsala and Nicolaus Copernicus - Co-operation with Wladyslaw Duczko2016Ingår i: Meetings at the borders: Studies dedicated to Professor Wladyslaw Duczko / [ed] Joanna Popielska-Grzybowska & Jadwiga Iwaszczuk, Pultusk: Pultusk Academy of Humanities 2016 , 2016, Vol. VKonferensbidrag (Refereegranskat)
    Abstract [en]

    The pagan Great Midwinter Sacrifice at Old Uppsala took place every eighth year. The starting date was defined by the full moon that occurred between 28 January and 26 February in the Gregorian calendar. By combining historical data and calculations of the dates of full moons, the author has established the exact years of the eight-year cycle. One such year was 852 CE. According to the rule of semi-legendary King Aun, the phases of the moon fell one day earlier after 304 years. Such displacements in the eight-year cycle took place in 1692, 1388, 1084, 780, and 476. King Aun is considered to have reigned about 450-500 CE and to have been buried at Old Uppsala. The three 'royal' burial mounds have been dated to 450-550 CE. They are oriented in such a way that they could have been used to regulate the sacrificial calendar. During excavations in 2013, two long rows of postholes were discovered. An 850 m long row was oriented towards the northern limit for the rising midwinter full moon on the earliest date, and the approximately 600 m long row was oriented towards the rising sun on 6-8 February. If it was a full moon on that day, the Great Midwinter Sacrifice the following year should begin on its earliest date.

    Identification of the tomb of Nicolaus Copernicus in the Cathedral in Frombork by DNA from his hair found in his copy of Calendarium Romanum Magnum by Stöffler, belonging to the Library at the Astronomical Observatorium in Uppsala.  

  • 47.
    Hesse, Sara
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för visuell information och interaktion.
    Holmin, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för visuell information och interaktion.
    Entreprenörers hantering av bergmodeller i E4 Förbifart Stockholm: En studie över hur utformningen av modell påverkar produktionen2017Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The goal of this master thesis is to study the challenges the contractors are experiencing when building in the project E4 The Stockholm Bypass (E4 Förbifart Stockholm) by using digital models. This is the first step for The Swedish Transport Administration towards the process of implementing BIM in the construction industry, which has led to several challenges and therefore is important to evaluate. The work of building E4 The Stockholm bypass can be seen with a sociotechnical perspective, since both humans and complex technology systems are involved in the project.

    The study used a qualitative method by interviewing the contractors, the promoters of the model and The Swedish Transport Administration. Furthermore, workshops were held with construction managers, BIM- specialists and the contractors’ measurement surveyors. The results were analysed by the theories regarding Human-Technology-Organisation (HTO), Human-Technology Interaction (HCI) with focus on usability and information management.

    The study resulted in a couple of recommendation to The Swedish Transport Administration. The main aspects were to involve the contractors earlier in the development of the models; have easily available information in the models necessary for production; change the contractors sceptical attitude towards BIM by listening to their issues; have a clear communication through the existing informations paths and create a common standard of format regarding exchange of information. By following the recommendations, the challenges regarding the work of the contractor will decrease and the implementation of models and BIM could proceed more efficiently. 

  • 48.
    Hoffmann, Inga
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Discovery of Novel Fatty Acid Dioxygenases and Cytochromes P450: Mechanisms of Oxylipin Biosynthesis in Pathogenic Fungi2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Dioxygenase-cytochrome P450 (DOX-CYP) fusion enzymes are present in diverse human and plant pathogenic fungi. They oxygenate fatty acids to lipid mediators which have regula­tory functions in fungal development and toxin production. These enzymes catalyze the for­mation of fatty acid hy­droperoxides which are subsequently converted by the P450 activities or reduced to the corresponding alcohols. The N-terminal DOX domains show catalytic and structural homology to mammalian cyclooxygenases, which belong to the most thoroughly studied human enzymes.

    7,8-Linoleate diol synthase (LDS) of the plant pathogenic fungus Gaeumannomyces graminis was the first characterized member of the DOX-CYP fusion enzyme family. It catalyzes the conversion of linoleic acid to 8R-hydroperoxylinoleic acid (HPODE) and subse­quently to 7S,8S-dihy­droxylinoleic acid by its DOX and P450 domains, respectively. By now, several enzymes with homology to 7,8-LDS have been identified in im­portant fungi, e.g., psi fac­tor-producing oxygenase (ppo)A, ppoB, and ppoC, of Aspergillus nidulans and A. fumigatus.

    By cloning and recombinant expression, ppoA of A. fumigatus was identi­fied as 5,8-LDS. Partial expression of the 8R-DOX domains of 5,8-LDS of A. fumigatus and 7,8-LDS of G. graminis yielded active protein which demonstrates that the DOX activities of LDS are independent of their P450 domains. The latter domains were shown to contain a conserved motif with catalytically important amide residues. As judged by site-directed mutagene­sis studies, 5,8- and 7,8-LDS seem to facilitate heterolytic cleavage of the oxygen-oxygen bond of 8R-HPODE by aid of a glutamine and an asparagine residue, respectively.

    Cloning and expression of putative DOX-CYP fusion proteins of A. terreus and Fusarium oxysporum led to the discovery of novel enzyme activities, e.g., linoleate 9S-DOX and two allene oxide synthases (AOS), specific for 9R- and 9S-HPODE, respectively. The fungal AOS are present in the P450 domains of two DOX-CYP fusion enzymes and show higher se­quence homology to LDS than to plant AOS and constitute therefore a novel class of AOS.

    In summary, this thesis describes the discovery of novel fatty acid oxy­genases of human and plant pathogenic fungi and the characterization of their reaction mechanisms.

    Delarbeten
    1. Expression of 5,8-LDS of Aspergillus fumigatus and its dioxygenase domain: a comparison with 7,8-LDS, 10-dioxygenase, and cyclooxygenase
    Öppna denna publikation i ny flik eller fönster >>Expression of 5,8-LDS of Aspergillus fumigatus and its dioxygenase domain: a comparison with 7,8-LDS, 10-dioxygenase, and cyclooxygenase
    2011 (Engelska)Ingår i: Archives of Biochemistry and Biophysics, ISSN 0003-9861, E-ISSN 1096-0384, Vol. 506, nr 2, s. 216-222Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    5,8-Linoleate diol synthase (5,8-LDS) of Aspergillus fumigatus was cloned, expressed, and compared with 7,8-LDS of the Take-all fungus. Replacements of Tyr and Cys in the conserved YRWH and FXXGPHXCLG sequences abolished 8R-dioxygenase (8-DOX) and hydroperoxide isomerase activities, respectively. The predicted α-helices of LDS were aligned with α-helices of cyclooxygenase-1 (COX-1) to identify the 8-DOX domains. N-terminal expression constructs of 5,8- and 7,8-LDS (674 of 1079, and 673 of 1165 residues), containing one additional α-helix compared to cyclooxygenase-1, yielded prominent 8R-DOX activities with apparently unchanged or slightly lower substrate affinities, respectively. Val-328 of 5,8-LDS did not influence the position of oxygenation in contrast to the homologous residues Val-349 of COX-1 and Leu-384 of 10R-dioxygenase. We conclude that ∼675 amino acids are sufficient to support 8-DOX activity.

    Nyckelord
    Cytochrome P450, fusion protein, heme-dependent peroxidase, hydroperoxide isomerase, LC-MS/MS, oxylipins
    Nationell ämneskategori
    Medicinsk bioteknologi (med inriktning mot cellbiologi (inklusive stamcellsbiologi), molekylärbiologi, mikrobiologi, biokemi eller biofarmaci)
    Forskningsämne
    Biokemisk farmakologi
    Identifikatorer
    urn:nbn:se:uu:diva-142985 (URN)10.1016/j.abb.2010.11.022 (DOI)000286961600014 ()21130068 (PubMedID)
    Tillgänglig från: 2011-01-18 Skapad: 2011-01-18 Senast uppdaterad: 2019-09-11
    2. 7,8- and 5,8-linoleate diol synthases support the heterolytic scission of oxygen-oxygen bonds by different amide residues.
    Öppna denna publikation i ny flik eller fönster >>7,8- and 5,8-linoleate diol synthases support the heterolytic scission of oxygen-oxygen bonds by different amide residues.
    2013 (Engelska)Ingår i: Archives of Biochemistry and Biophysics, ISSN 0003-9861, E-ISSN 1096-0384, Vol. 539, nr 1, s. 87-91Artikel i tidskrift (Övrigt vetenskapligt) Published
    Abstract [en]

    Linoleate diol synthases (LDS) are fungal dioxygenase-cytochrome P450 fusion enzymes. They oxidize 18:2n-6 sequentially to 8R-hydroperoxylinoleic acid (8R-HPODE) and 7S,8S- or 5S,8R-dihydroxylinoleic acids (DiHODE) by intramolecular oxygen transfer. The P450 domains contain a conserved sequence, Ala-Asn-Gln-Xaa-Gln, presumably located in the I-helices. The Asn938Leu replacement of 7,8-LDS of Gaeumannomyces graminis virtually abolished and the Asn938Asp and Asn938Gln replacements reduced the hydroperoxide isomerase activity. Gln941Leu and Gln941Glu substitutions had little effects. Replacements of the homologous Asn(887) and Gln(890) residues of 5,8-LDS of Aspergillus fumigatus yielded the opposite results. Asn887Leu and Asn887Gln of 5,8-LDS retained 5,8-DiHODE as the main metabolite with an increased formation of 6,8- and 8,11-DiHODE, whereas Gln890Leu almost abolished the 5,8-LDS activity. Replacement of Gln(890) with Glu also retained 5,8-DiHODE as the main product, but shifted oxygenation from C-5 to C-7 and C-11 and to formation of epoxyalcohols by homolytic scission of 8R-HPODE. P450 hydroxylases usually contain an "acid-alcohol" pair in the I-helices for the heterolytic scission of O-2 and formation of compound I (Por(+.) Fe(IV)=0) and water. The function of the acid-alcohol pair appears to be replaced by two different amide residues, Asn(938) of 7,8-LDS and Gln(890) of 5,8-LDS, for heterolysis of 8R-HPODE to generate compound I. 

    Nationell ämneskategori
    Annan naturvetenskap Biokemi och molekylärbiologi
    Forskningsämne
    Farmaceutisk biokemi; Farmaceutisk vetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-206083 (URN)10.1016/j.abb.2013.09.010 (DOI)000326136000010 ()
    Tillgänglig från: 2013-08-29 Skapad: 2013-08-27 Senast uppdaterad: 2017-12-06Bibliografiskt granskad
    3. Novel insights into cyclooxygenases, linoleate diol synthases, and lipoxygenases from deuterium kinetic isotope effects and oxidation of substrate analogs
    Öppna denna publikation i ny flik eller fönster >>Novel insights into cyclooxygenases, linoleate diol synthases, and lipoxygenases from deuterium kinetic isotope effects and oxidation of substrate analogs
    2012 (Engelska)Ingår i: Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids, ISSN 1388-1981, E-ISSN 1879-2618, Vol. 1821, nr 12, s. 1508-1517Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Cyclooxygenases (COX) and 8R-dioxygenase (8R-DOX) activities of linoleate diol synthases (LDS) are homologous heme-dependent enzymes that oxygenate fatty acids by a tyrosyl radical-mediated hydrogen abstraction and antarafacial insertion of O2. Soybean lipoxygenase-1 (sLOX-1) contains non-heme iron and oxidizes 18:2n-6 with a large deuterium kinetic isotope effect (D-KIE). The aim of the present work was to obtain further mechanistic insight into the action of these enzymes by using a series of n-6 and n-9 fatty acids and by analysis of D-KIE. COX-1 oxidized C20 and C18 fatty acids in the following order of rates: 20:2n-6 > 20:1n-6 > 20:3n-9 > 20:1n-9 and 18:3n-3 ≥ 18:2n-6 > 18:1n-6. 18:2n-6 and its geometrical isomer (9E,12Z)18:2 were both mainly oxygenated at C-9 by COX-1, but the 9Z,12E isomer was mostly oxygenated at C-13. A cis-configured double bond in the n-6 position therefore seems important for substrate positioning. 8R-DOX oxidized (9Z,12E)18:2 at C-8 in analogy with 18:2n-6, but the 9E,12Z isomer was only subject to hydrogen abstraction at C-11 and oxygen insertion at C-9 by 8R-DOX of 5,8-LDS. sLOX-1 and 13R-MnLOX oxidized [11S-2H]18:2n-6 with similar D-KIE (~53), which implies that the catalytic metals did not alter the D-KIE. Oxygenation of 18:2n-6 by COX-1 and COX-2 took place with a D-KIE of 3-5 as probed by incubations of [11,11-2H2]- and [11S-2H]18:2n-6. In contrast, the more energetically demanding hydrogen abstractions of the allylic carbons of 20:1n-6 by COX-1 and 18:1n-9 by 8R-DOX were both accompanied by large D-KIE (>20).

    Nyckelord
    Animal heme peroxidase, Chiral phase HPLC, Fatty acid oxygenation, Kinetic isotope effect, Mass spectrometry, Oxygenation mechanism
    Nationell ämneskategori
    Biokemi och molekylärbiologi
    Forskningsämne
    Biokemisk farmakologi
    Identifikatorer
    urn:nbn:se:uu:diva-181786 (URN)10.1016/j.bbalip.2012.09.001 (DOI)000310100900007 ()
    Forskningsfinansiär
    Knut och Alice Wallenbergs Stiftelse, KAW 2004.0123Vetenskapsrådet, 06523
    Tillgänglig från: 2012-09-28 Skapad: 2012-09-28 Senast uppdaterad: 2018-06-27Bibliografiskt granskad
    4. Linoleate 9R-dioxygenase and allene oxide synthase activities of Aspergillus terreus
    Öppna denna publikation i ny flik eller fönster >>Linoleate 9R-dioxygenase and allene oxide synthase activities of Aspergillus terreus
    2010 (Engelska)Ingår i: Archives of Biochemistry and Biophysics, ISSN 0003-9861, E-ISSN 1096-0384, Vol. 495, nr 1, s. 67-73Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Oxygenation of linoleic acid by Aspergillus terreus was studied with LC-MS/MS. 9(R)-Hydroperoxy-10(E),12(Z)-octadecadienoic acid (9R-HpODE) was identified along with 10(R)-hydroxy-8(E),12(Z)-octadecadienoic acid and variable amounts of 8(R)-hydroxy-9(Z),12(Z)-octadecadienoic acid. 9R-HpODE was formed from [11S-2H]18:2n-6 with loss of the deuterium label, suggesting antarafacial hydrogen abstraction and oxygenation. Two polar metabolites were identified as 9-hydroxy-10-oxo-12(Z)-octadecenoic acid (alpha-ketol) and 13-hydroxy-10-oxo-11(E)-octadecenoic acid (gamma-ketol), likely formed by spontaneous hydrolysis of an unstable allene oxide, 9(R),10-epoxy-10,12(Z)-octadecadienoic acid. alpha-Linolenic acid and 20:2n-6 were oxidized to hydroperoxy fatty acids at C-9 and C-11, respectively, but alpha- and gamma-ketols of these fatty acids could not be detected. The genome of A. terreus lacks lipoxygenases, but contains genes homologous to 5,8-linoleate diol synthases and linoleate 10R-dioxygenases of aspergilli. Our results demonstrate that linoleate 9R-dioxygenase linked to allene oxide synthase activities can be expressed in fungi.

    Nyckelord
    Catalase, Cytochrome P450, 9R-HpODE, Heme peroxidase, Jasmonic acid, Oxygenation mechanism, Potato stolons
    Nationell ämneskategori
    Farmaceutiska vetenskaper
    Identifikatorer
    urn:nbn:se:uu:diva-122731 (URN)10.1016/j.abb.2009.12.022 (DOI)000275137000011 ()20043865 (PubMedID)
    Tillgänglig från: 2010-04-20 Skapad: 2010-04-16 Senast uppdaterad: 2019-09-11
    5. Expression of Fusion Proteins of Aspergillus terreus Reveals a Novel Allene Oxide Synthase
    Öppna denna publikation i ny flik eller fönster >>Expression of Fusion Proteins of Aspergillus terreus Reveals a Novel Allene Oxide Synthase
    2013 (Engelska)Ingår i: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 288, nr 16, s. 11459-11469Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Aspergilli oxidize C-18 unsaturated fatty acids by dioxygenase-cytochrome P450 fusion proteins to signal molecules involved in reproduction and host-pathogen interactions. Aspergillus terreus expresses linoleate 9R-dioxygenase (9R-DOX) and allene oxide synthase (AOS) activities in membrane fractions. The genome contains five genes (ATEG), which may code for a 9R-DOX-AOS fusion protein. The genes were cloned and expressed, but none of them oxidized 18:2n-6 to 9R-hydroperoxy-10(E), 12(Z)-octadecadienoic acid (9R-HPODE). ATEG_02036 transformed 9R-HPODE to an unstable allene oxide, 9(R), 10-epoxy-10,12(Z)-octadecadienoic acid. A substitution in the P450 domain (C1073S) abolished AOS activity. The N964V and N964D mutants both showed markedly reduced AOS activity, suggesting that Asn(964) may facilitate homolytic cleavage of the dioxygen bond of 9R-HPODE with formation of compound II in analogy with plant AOS (CYP74) and prostacyclin synthase (CYP8A1). ATEG_03992 was identified as 5,8-linoleate diol synthase (5,8-LDS). Replacement of Asn(878) in 5,8-LDS with leucine (N878L) mainly shifted ferryl oxygen insertion from C-5 toward C-6, but replacements of Gln(881) markedly affected catalysis. The Q881L mutant virtually abolished the diol synthase activity. Replacement of Gln(881) with Asn, Glu, Asp, or Lys residues augmented the homolytic cleavage of 8R-HPODE with formation of 10-hydroxy-8(9)-epoxy-12(Z)-octadecenoic acid (erythro/threo, 1-4:1) and/or shifted ferryl oxygen insertion from C-5 toward C-11. We conclude that homolysis and heterolysis of the dioxygen bond with formation of compound II in AOS and compound I in 5,8-LDS are influenced by Asn and Gln residues, respectively, of the I-helices. AOS of A. terreus appears to have evolved independently of CYP74 but with an analogous reaction mechanism.

    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-200688 (URN)10.1074/jbc.M113.458257 (DOI)000317915500047 ()
    Tillgänglig från: 2013-06-03 Skapad: 2013-06-03 Senast uppdaterad: 2019-09-11
    6. Discovery of a linoleate 9S-dioxygenase and an allene oxide synthase in a fusion protein of Fusarium oxysporum
    Öppna denna publikation i ny flik eller fönster >>Discovery of a linoleate 9S-dioxygenase and an allene oxide synthase in a fusion protein of Fusarium oxysporum
    2013 (Engelska)Ingår i: Journal of Lipid Research, ISSN 0022-2275, E-ISSN 1539-7262, Vol. 54, nr 12, s. 3417-3480Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Fusarium oxysporum is a devastating plant pathogen that oxidizes C-18 fatty acids sequentially to jasmonates. The genome codes for putative dioxygenase (DOX)-cytochrome P450 (CYP) fusion proteins homologous to linoleate diol synthases (LDSs) and the allene oxide synthase (AOS) of Aspergillus terreus, e. g., FOXB_01332. Recombinant FOXB_01332 oxidized 18:2n-6 to 9S-hydroperoxy-10(E), 12(Z)-octadecadienoic acid by hydrogen abstraction and antarafacial insertion of molecular oxygen and sequentially to an allene oxide, 9S(10)-epoxy-10,12(Z)-octadecadienoic acid, as judged from nonenzymatic hydrolysis products (alpha- and gamma-ketols). The enzyme was therefore designated 9S-DOX-AOS. The 9S-DOX activity oxidized C-18 and C-20 fatty acids of the n-6 and n-3 series to hydroperoxides at the n-9 and n-7 positions, and the n-9 hydroperoxides could be sequentially transformed to allene oxides with only a few exceptions. The AOS activity was stereospecific for 9- and 11-hydroperoxides with S configurations. FOXB_01332 has acidic and alcoholic residues, Glu(946)-Val-Leu-Ser(949), at positions of crucial Asn and Gln residues (Asn-Xaa-Xaa-Gln) of the AOS and LDS. Site-directed mutagenesis studies revealed that FOXB_01332 and AOS of A. terreus differ in catalytically important residues suggesting that AOS of A. terreus and F. oxysporum belong to different subfamilies. FOXB_01332 is the first linoleate 9-DOX with homology to animal heme peroxidases and the first 9-DOX-AOS fusion protein.

    Nationell ämneskategori
    Biokemi och molekylärbiologi Annan naturvetenskap
    Forskningsämne
    Farmaceutisk biokemi; Farmaceutisk vetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-206088 (URN)10.1194/jlr.M044347 (DOI)000330534900023 ()
    Tillgänglig från: 2013-08-29 Skapad: 2013-08-27 Senast uppdaterad: 2017-12-06Bibliografiskt granskad
  • 49.
    Hoffmann, Inga
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Oliw, Ernst H.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    7,8- and 5,8-linoleate diol synthases support the heterolytic scission of oxygen-oxygen bonds by different amide residues.2013Ingår i: Archives of Biochemistry and Biophysics, ISSN 0003-9861, E-ISSN 1096-0384, Vol. 539, nr 1, s. 87-91Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Linoleate diol synthases (LDS) are fungal dioxygenase-cytochrome P450 fusion enzymes. They oxidize 18:2n-6 sequentially to 8R-hydroperoxylinoleic acid (8R-HPODE) and 7S,8S- or 5S,8R-dihydroxylinoleic acids (DiHODE) by intramolecular oxygen transfer. The P450 domains contain a conserved sequence, Ala-Asn-Gln-Xaa-Gln, presumably located in the I-helices. The Asn938Leu replacement of 7,8-LDS of Gaeumannomyces graminis virtually abolished and the Asn938Asp and Asn938Gln replacements reduced the hydroperoxide isomerase activity. Gln941Leu and Gln941Glu substitutions had little effects. Replacements of the homologous Asn(887) and Gln(890) residues of 5,8-LDS of Aspergillus fumigatus yielded the opposite results. Asn887Leu and Asn887Gln of 5,8-LDS retained 5,8-DiHODE as the main metabolite with an increased formation of 6,8- and 8,11-DiHODE, whereas Gln890Leu almost abolished the 5,8-LDS activity. Replacement of Gln(890) with Glu also retained 5,8-DiHODE as the main product, but shifted oxygenation from C-5 to C-7 and C-11 and to formation of epoxyalcohols by homolytic scission of 8R-HPODE. P450 hydroxylases usually contain an "acid-alcohol" pair in the I-helices for the heterolytic scission of O-2 and formation of compound I (Por(+.) Fe(IV)=0) and water. The function of the acid-alcohol pair appears to be replaced by two different amide residues, Asn(938) of 7,8-LDS and Gln(890) of 5,8-LDS, for heterolysis of 8R-HPODE to generate compound I. 

  • 50.
    Hoffmann, Inga
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Oliw, Ernst H.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Discovery of a linoleate 9S-dioxygenase and an allene oxide synthase in a fusion protein of Fusarium oxysporum2013Ingår i: Journal of Lipid Research, ISSN 0022-2275, E-ISSN 1539-7262, Vol. 54, nr 12, s. 3417-3480Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fusarium oxysporum is a devastating plant pathogen that oxidizes C-18 fatty acids sequentially to jasmonates. The genome codes for putative dioxygenase (DOX)-cytochrome P450 (CYP) fusion proteins homologous to linoleate diol synthases (LDSs) and the allene oxide synthase (AOS) of Aspergillus terreus, e. g., FOXB_01332. Recombinant FOXB_01332 oxidized 18:2n-6 to 9S-hydroperoxy-10(E), 12(Z)-octadecadienoic acid by hydrogen abstraction and antarafacial insertion of molecular oxygen and sequentially to an allene oxide, 9S(10)-epoxy-10,12(Z)-octadecadienoic acid, as judged from nonenzymatic hydrolysis products (alpha- and gamma-ketols). The enzyme was therefore designated 9S-DOX-AOS. The 9S-DOX activity oxidized C-18 and C-20 fatty acids of the n-6 and n-3 series to hydroperoxides at the n-9 and n-7 positions, and the n-9 hydroperoxides could be sequentially transformed to allene oxides with only a few exceptions. The AOS activity was stereospecific for 9- and 11-hydroperoxides with S configurations. FOXB_01332 has acidic and alcoholic residues, Glu(946)-Val-Leu-Ser(949), at positions of crucial Asn and Gln residues (Asn-Xaa-Xaa-Gln) of the AOS and LDS. Site-directed mutagenesis studies revealed that FOXB_01332 and AOS of A. terreus differ in catalytically important residues suggesting that AOS of A. terreus and F. oxysporum belong to different subfamilies. FOXB_01332 is the first linoleate 9-DOX with homology to animal heme peroxidases and the first 9-DOX-AOS fusion protein.

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