135 research outputs found
On the antiporter-like subunits of respiratory chain Complex I - implications for the evolution and coupling mechanism of the NADH:quinone oxidoreductase enzyme complex
No full textComplex I or NADH:quinone oxidoreductase is the largest enzyme complex, but the least understood energy coupling site in the respiratory chain of mitochondria and bacteria. No high-resolution structural information exists for this enzyme and the molecular mechanism that couples electron transfer and proton pumping is not understood. In mammals, about 50% of the mitochondrial DNA is encoding protein subunits of Complex I, and thus there is a strong correlation between defect Complex I and various degenerative diseases. Learning more about Complex I is thus important both for basic science and for medicine. Complex I contains three large membrane-spanning subunits, NuoL, NuoM and NuoN, that are homologous to one particular class of Na+/H+ antiporters and therefore are likely to harbor important components of the proton translocation machinery. MrpA and MrpD belong to this class of Na+/H+ antiporters and are found in a gene cluster containing seven genes, mrpA-G. In this work the transmembrane topology of the antiporter-like subunits was determined and their phylogenetic relationship investigated. In the analysis MrpA and MrpD formed distinct branches where NuoL grouped with MrpA and NuoM/N with MrpD. The result suggest that there are functional differences between the MrpA/NuoL and MrpD/NuoM proteins. The remaining proteins encoded by the mrp gene cluster were analyzed by PSI-BLAST, a bioinformatical search tool that more efficiently detect distant homologies. MrpC was found to be a NuoK homologue, and thus we conclude that NuoK, NuoL and NuoM where recruited together to Complex I, from the antiporter module MrpC, MrpA and MrpD. A functional difference between MrpA and MrpD was confirmed using Bacillus subtilis mrpA and mrpD deletion strains that were more salt and pH sensitive than wild type cells, but to a different extent. Recent work by Julia Steubers group at ETH Zürich showed that Complex I from Escherichia coli could translocate Na+, but this has hitherto not been regarded as a general property of proton pumping Complex I. By expressing the Complex I subunits NuoL and NuoM from the alpha-proteobacteria Rhodobacter capsulatus in the B. subtilis deletion strains we have demonstrated that these subunits are capable of Na+ translocation in vivo. Since R. capsulatus Complex I is more closely related to mitochondrial Complex I than to the E. coli enzyme, it is very likely that all Complex I enzymes have the ability to translocate Na+ as well as H+
The Indoor People's Nature
No full textWe spend most of our lives indoors. In this book, Danish anthropologist Cecilie Rubow explores the impact that this way of life has on our understanding of nature and our approach to dealing with the ecological crises the world faces. The author follows in the footsteps of beach people, bird people, environmentalists and climate activists. It is a journey full of magic, surprises and critique, which leads to the realisation that there is not just one nature, but many, and that we come across it where least expected. The book also serves an introduction to new anthropological thinking about how ecological crises call for new ways of conceptualising nature
Samarbeid mellom barnehage, skole og skolefritidsordning for en trygg og god overgang. -en studie om ansattes beskrivelser av samarbeidet mellom barnehage, skole og skolefritidsordning for å legge til rette for en trygg og god overgang for barn med utfordrende atferd.
No full textSammendrag
Denne masteroppgaven belyser hvordan ansatte i barnehager, skoler og skolefritidsordninger beskriver samarbeidet om overgangen mellom disse institusjonene for barn med utfordrende atferd. Overgangen fra barnehage til skole og skolefritidsordning vil for mange barn kunne innebære en stor endring i hverdagen. Formålet med studien er å undersøke problemstillingen “Hvordan beskriver ansatte i barnehager, skoler og skolefritidsordninger samarbeidet for å legge til rette for en trygg og god overgang fra barnehage til skole og SFO for barn med utfordrende atferd?”
Studiens problemstilling ble undersøkt gjennom et kvalitativt forskningsdesign hvor fokusgruppeintervju ble benyttet. Utvalget i studien bestod av pedagogiske ledere i barnehager, lærere i barneskoler, avdelingsledere i skoler og SFO-ledere, til sammen 16 ansatte. Barnehagene og skolene/SFO-ene som deltok i studien hadde ingen direkte tilknytning til hverandre.
Den teoretiske forankringen i studien er ulike vinklinger på overgangsprosesser og viktigheten av kontinuitet i overganger, Dewey sin teori om kontinuitet i erfaring og Bronfenbrenners utviklingsøkologiske modell. Relevante elementer innen organisasjonsteori vil være med å belyse ulike sider ved tverrfaglig samarbeid.
Studien viser at ansatte både i barnehagene, skolene og SFO anser samarbeidet som viktig for å legge til rette for en trygg og god overgang for barn med utfordrende atferd. Samarbeidet de ansatte beskriver omfatter en praksis hvor ansatte legger til rette for besøk til skolen, samt ulike aktiviteter slik at barnet kan gjøre seg kjent med skolen. Videre vektlegges informasjonsdeling mellom institusjonene. Spesielt fremheves fordelen ved at ansatte kan møtes “ansikt-til-ansikt". Treffpunkter mellom ansatte fremheves som viktig for å kunne skape en god dialog.
Et interessant funn i studien omhandler SFO sin rolle i overgangen for barn med utfordrende atferd. På tross av at SFO fremheves å ha en viktig rolle i overgangen, beskriver pedagogiske ledere et fravær av samarbeid med SFO. Skolen og SFO på sin side beskriver et godt og tett samarbeid dem imellom.
Studien viser samtidig at ansatte beskriver ulike utfordringer i samarbeidet. Begrenset innsikt og manglende felles forståelse er forhold som oppleves å utfordre samarbeidet. Skolen beskriver samarbeidet som tidkrevende og omfattende, og barnehagene beskriver hvordan de opplever at samarbeidspraksisen varierer fra skole til skole
Phylogeny and biogeography of the lamioid mint genus Phlomis L.
No full textAbstract
Classification of the lamioid mint genus Phlomis L., which comprises more than 100 species distributed in Asia, southern Europe and northern Africa, has so far been the subject of few, mainly morphological studies. The present research represents the first molecular phylogenetic study of the genus in which taxa representative of the entire genus are included. In contrast to considerable morphological and ecological variation among taxa, sequence variation in the trnL intron and the trnL-trnF intergenic spacer was remarkably low, which when analysed, resulted in sparse phylogenetic resolution, especially among the south-west Asian and the Mediterranean taxa. However, these phylogenetic results were still informative regarding Phlomis classification and biogeography. The results support a split of the genus into two separate groups; the taxonomic ranks of these groups as either genera or sections can be disputed. I choose here to recognise these clades as separate genera in order to decrease the taxonomic complexity of Phlomis. The close relationship between Phlomis and Eremostachys Bunge, pointed out by several authors, is confirmed in this study, and in a noteworthy new finding, the small Asian genus Notochaete Benth. is more closely related to Phlomis than previously assumed. Both Eremostachys and Notochaete are in fact nested within one of the clades of Phlomis s.l., here recognised as the genus Phlomoides Moench. Character optimisation analyses based on geographic distributions of all taxa show that the groups obtained by molecular phylogenetic analysis correlate well with biogeography. The results suggest that Phlomis s.l. has a south-west Asian origin in the area around Western China
Formidling av dataspill som kulturarv: En kulturpolitisk undersøkelse
No full textDenne masteroppgaven ble basert på en fremvekst av spesialmuseer fokusert på dataspill rundt i Europa nå i nyere tid. I Norge har vi ikke et museum dedikert til å formidle om spillkultur og historie, men det har blitt noen formidlingsprosjekter de siste årene som setter et fokus på dataspill. Kulturarv som et begrep kan oppfattes på mange ulike måter, men det er en forståelse av at dataspill som kulturarv er mer enn bare gjenstander eller underholdning. Det er også aktiv kultur, en tidligere historie og en levende industri. Kulturpolitikk har vært koblet til dataspill på mange måter, gjennom blant annet generelle kulturpolitiske retninger, støtteordninger, lovendringer og organisatoriske grep. Undersøkelsen i oppgaven så derfor på koblingen mellom dataspill og kulturpolitikk, og så etter: Hvordan kan kulturpolitikk påvirke formidling av dataspill som kulturarv? I arbeidet med å lete etter påvirkningskilder, har jeg benyttet meg av tre semistrukturerte forskningsintervjuer og dokumentanalyse av kulturpolitiske dokumenter. Resultatet mellom de to undersøkelsene var et gap som måtte prøves å tolke å forstå de kulturpolitiske virkemidlene. Undersøkelsen ble brutt ned i ulike kategorier og områder for å se dypere ned på hvordan kulturpolitikken kan ha påvirket feltet for formidling av dataspill som kulturarv. Oppgaven drøfter frem til at kulturpolitikk har vært en viktig drivkraft for utvikling av dataspillfeltet, og identifiserer ulike påvirkningskrefter som har hatt en rolle.
This master's thesis was based on an emergence of special museums focused on computer games around Europe now in newer times. In Norway, we do not have a museum dedicated to computer games, culture and history, but there have been some projects in recent years that focus on computer games. Cultural heritage as a term can be perceived in many different ways, but there is an understanding that computer games as cultural heritage is more than just objects or entertainment. They are also an active culture, a history and a vibrant industry. Cultural policy has been connected to computer games in many ways, and among many things: general cultural policy guidelines, financial support, legislative changes and organizational measures. The investigation in the thesis therefore looks at the link between computer games and cultural policy, and research: How can cultural policy affect the dissemination of computer games as cultural heritage? In the work of looking for sources of influence, I have used the research design of three semi-structured research interviews and document analysis of cultural policy documents. The result between the two research methods showed a gap that had to be interpreted to understand the cultural policy instruments at work. The research was then broken down into different categories and areas, to look deeper into how cultural policy may have influenced the field of dissemination of computer games as cultural heritage. The paper discusses that cultural policy has been an important driving force for the development of the computer game field and identifies various influencing forces that have played a role.publishedVersio
The ‘antiporter module’ of respiratory chain Complex I includes the MrpC/NuoK subunit – a revision of the modular evolution scheme
No full textAbstractRespiratory chain Complex I or NADH:quinone oxidoreductase catalyzes oxidation of NADH in the mitochondrial matrix or bacterial cytoplasm and reduction of quinone in the membrane, coupled to pumping of 4H+/2e− across the membrane. The same enzyme complex is also capable of the reverse reaction, i.e. ΔμH+-supported NAD+ reduction. The molecular mechanism that couples electron transfer to proton pumping is not understood. The Complex I enzyme, containing 14 protein subunits necessary for function, has evolved from smaller functional building blocks. Three Complex I protein subunits, NuoL, NuoM and NuoN, show primary sequence similarity to one particular class of antiporters, and are thus predicted to play a role in the proton translocation machinery. These antiporters, MrpA and MrpD are encoded by a conserved gene cluster, that contains seven genes. In previous work we have determined that these antiporters come in two subclasses, MrpA-type and MrpD-type, and that the Complex I subunit NuoL is more closely related to MrpA and NuoM and N are more closely related to the MrpD antiporter. This implied that both MrpA and MrpD had been recruited to Complex I, rather than arising from gene duplications of one antiporter encoding gene. In this work we show that MrpC and NuoK are homologous proteins. The most plausible explanation for these findings is that a multisubunit antiporter complex was recruited to the ancestral enzyme. We further conclude that the last common ancestor of the Complex I enzyme family and membrane bound NiFe hydrogenases of type 3 and 4 contained the NuoKLMN subunit module
Transmembrane topology of the NuoL, M and N subunits of NADH:quinone oxidoreductase and their homologues among membrane-bound hydrogenases and bona fide antiporters
No full textAbstractNicotinamide adenine dinucleotide—reduced form (NADH):quinone oxidoreductase (respiratory Complex I), F420H2 oxidoreductase and complex, membrane-bound NiFe-hydrogenase contain protein subunits homologous to a certain type of bona fide antiporters. In Complex I, these polypeptides (NuoL/ND5, NuoM/ND4, NuoN/ND2) are most likely core components of the proton pumping mechanism, and it is thus important to learn more about their structure and function. In this work, we have determined the transmembrane topology of one such polypeptide, and built a 2D structural model of the protein valid for all the homologous polypeptides. The experimentally determined transmembrane topology was different from that predicted by majority vote hydrophobicity analyses of members of the superfamily. A detailed phylogenetic analysis of a large set of primary sequences shed light on the functional relatedness of these polypeptides
Mycena species can be opportunist-generalist plant root invaders
No full textACKNOWLEDGEMENTS We thank Karl-Henrik Larsson and Arne Aronsen for provisions of specimens from the Natural History Museum of Oslo and help with the identification of field specimens from Svalbard. We further thank Cecilie Mathiesen and Mikayla Jacobs for technical assistance in the laboratory, Brendan J. Furneaux for valuable input to the R script, and the curators of H, TUR, and OULU. The Mycena ITS sequences originating from the specimens deposited in H, TUR, and OULU were produced as part of the Finnish Barcode of Life Project (FinBOL) funded by the Ministry of Environment, Finland (YM23/5512/2013), Otto A Malm's Donationsfond, and the Kone Foundation. We thank the European Commission (grant no. 658849) and the Carlsberg Foundation (grant no. CF18-0809) for grants to C.B. Harder that made this research possible. C.B. Harder was financed by a grant from the Danish Independent Research Fund DFF/FNU 2032-00064B (SapMyc) at the time of writing.Peer reviewe
Acting Experience and Imagination
No full textThis work focuses on the theme of the actor´s internal experience and imagination. It is not a typical theoretical study, but rather a subjective contemplation of the material. In this review, the author is primarily concerned with two roles playd at the school theatre Disk in the 2005/2006 season: Cecilie (B.M.Koltés- Quay West) and 1st Woman (Chorus; Euripidés-Orestes
The 'antiporter module' of respiratory chain Complex I includes the MrpC/NuoK subunit - a revision of the modular evolution scheme
No full textRespiratory chain Complex I or NADH:quinone oxidoreductase catalyzes oxidation of NADH in the mitochondrial matrix or bacterial cytoplasm and reduction of quinone in the membrane, coupled to pumping of 4H+/2e- across the membrane. The same enzyme complex is also capable of the reverse reaction, i.e. @D@mH+-supported NAD+ reduction. The molecular mechanism that couples electron transfer to proton pumping is not understood. The Complex I enzyme, containing 14 protein subunits necessary for function, has evolved from smaller functional building blocks. Three Complex I protein subunits, NuoL, NuoM and NuoN, show primary sequence similarity to one particular class of antiporters, and are thus predicted to play a role in the proton translocation machinery. These antiporters, MrpA and MrpD are encoded by a conserved gene cluster, that contains seven genes. In previous work we have determined that these antiporters come in two subclasses, MrpA-type and MrpD-type, and that the Complex I subunit NuoL is more closely related to MrpA and NuoM and N are more closely related to the MrpD antiporter. This implied that both MrpA and MrpD had been recruited to Complex I, rather than arising from gene duplications of one antiporter encoding gene. In this work we show that MrpC and NuoK are homologous proteins. The most plausible explanation for these findings is that a multisubunit antiporter complex was recruited to the ancestral enzyme. We further conclude that the last common ancestor of the Complex I enzyme family and membrane bound NiFe hydrogenases of type 3 and 4 contained the NuoKLMN subunit module
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