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Uppsala universitet Samhällsvetenskap
N/A / Link / Rydén , Göran / 2006

Polyblastia A. Massal. is a genus of lichenized fungi belonging to Verrucariaceae (Ascomycota). Traditional classification heavily rested on a few cardinal characters, primarily ascoma structure and spore morphology, but the delimitation of Polyblastia was problematic. Using DNA sequences from nucLSU, and RPB1 the position of the ‘Polyblastia group’, as a strongly supported clade within Verrucariaceae, was confirmed. A three marker phylogeny (including nucITS) based on a wide taxon sampling reveals strongly supported clades within the ‘Polyblastia group’. Thus Polyblastia s.str. is recognized. The phylogeny of the strongly supported Thelidium clade is not completely resolved. In a different clade, Verrucaria rupestris, the type of Verrucaria, is a sister to the Henrica melaspora/H. theleodes clade. Trimmatothele perquisita, the type of Trimmatothele, forms a strongly supported group with a Verrucaria species. The genus Sporodictyon, until recently included in Polyblastia, is resurrected.Species delimitation in Sporodictyon is investigated, and the morphological variation within and between the monophyletic groups is evaluated in an effort to reconcile morphological and molecular data. A taxonomic revision of Sporodictyon, occurring in Northern Europe and the adjacent Arctic is provided, and two new species are described. A comprehensive material is investigated, a key to the species is provided.A generic revision of the family Verrucariaceae, based on recent molecular phylogenetic analyses and previous morphological studies, is offered. Three new genera (Hydropunctaria, Parabagliettoa and Wahlenbergiella) are proposed. Several other monophyletic groups are identified for which the taxon sampling is insufficient for proposing taxonomic changes. The nomenclature of the genera in the family is revised, including the study of type materials and several lectotypifications are suggested.The new genus Atla (Verrucariaceae) is described, and three new species to science, A. alpina, A. palicei and A. praetermissa, are included. An identification key to the species and a revision of the genus is supplied.
978-91-554-7035-7 / Link / Savić , Sanja / 2007

N/A / Link / Nylander , Johan A. A. /

Uppsala universitet Företagsekonomi
To manage change in an organization is difficult, but it is even more difficult to change the methods of change. In this report (written in Swedish) we present a study of change in a public service media organization - the Swedish Television (SVT).SVT finds itself, since several years, in a situation of radical change. Changes concern the market situation, with new media entering the television industry and increased competition. Cost cutting, outsourcing, and reorganizations are recurrent, and work roles and competence profiles change for professionals in the company. The use of digitalized and IT-based technology creates a new technological context. Archives and copyrights are more important than ever. The role of public service is also subject to political discussion.To meet this rapidly changing environment, actors within the company wanted to develop the way of leading and managing change in the organization. In this research project we followed a part of the company during 2004 - 2007. Leaders wanted to support broader participation in the change process, and further develop as a learning organization, with strengthened abilities of knowledge sharing and knowledge creation. The tradition had been to use more expert driven forms of change and top down implementation. Top management, many (but not all) middle managers, technicians, and employees shared the view that the company’s way of working with change ought to be changed.However, in spite of good aspirations, it showed to be difficult to change the methods of change in practise, and in this study we try to explain why. The analysis shows some deeply rooted characteristics in the organization. These characteristics are common in many other large organizations, so we have no reason to believe that SVT is unique or less developed when it comes to leadership, organizing or change methods. Instead, we would like to contribute with some in-dept knowledge that can be put in use when organizations strive to generate constructive change processes.In the report we describe how the internal dialogue about the change methods was given low priority, and how established communication patterns favoured expert- and technology driven change, rather than broad participation and collective learning. The study also illustrates how a knowledge based (or learning oriented) perspective on change tends to collide with technology oriented and expert driven change logic. It was hard to combine these parallel, but not explicitly outspoken, attitudes and beliefs, concerning for instance, competence, employee’s participations, cost calculating, buyer – deliver relations, and roles in the change process.It is argued in the report that the colliding logics in these areas cause a creative tension that could be constructively taken care of in change processes. It is also argued that both a technological/ expert driven rationality and a knowledge-based (or learning oriented) perspective, should be taken actively into consideration in times of radical organizational change.
N/A / Link / Larsson , Pär / 2008

N/A / Link / Guzzini , Stefano / 2003

91-7203-938-8 / Link / Blanck , Dag / 2000

ObjectiveTo assess the use of hyperventilation and the adherence to Brain Trauma Foundation-Guidelines (BTF-G) after traumatic brain injury (TBI).SettingTwenty-two European centers are participating in the BrainIT initiative.DesignRetrospective analysis of monitoring data.Patients and participantsOne hundred and fifty-one patients with a known time of trauma and at least one recorded arterial blood–gas (ABG) analysis.Measurements and resultsA total number of 7,703 ABGs, representing 2,269 ventilation episodes(VE) were included in the analysis. Related minute-by-minute ICP data were taken from a 30 min time window around each ABG collection. Data are given as mean with standard deviation. (1) Patients without elevated intracranial pressure (ICP) (\20 mmHg) manifested a statistically significant higher PaCO2(36 ± 5.7 mmHg) in comparison to patients with elevated ICP(C20 mmHg; PaCO2:34 ± 5.4 mmHg, P\0.001). (2) Intensified forced hyperventilation(PaCO2 B 25 mmHg) in the absence of elevated ICP was found in only 49VE (2%). (3) Early prophylactic hyperventilation (\24 h after TBI;PaCO2 B 35 mmHg,ICP\20 mmHg) was used in 1,224VE (54%). (4) During forced hyperventilation(PaCO2 B 30 mmHg), simultaneous monitoring of brain tissue pO2 or SjvO2 was used in only 204 VE (9%).ConclusionWhile overall adherence to current BTF-Gseems to be the rule, its recommendations on early prophylactic hyperventilation as well as the use of additional cerebral oxygenation monitoring during forced hyperventilation are not followed in this sample of European TBI centers.DescriptorNeurotrauma
N/A / Link / Neumann , JO / 2008

N/A / Link / Ljungkvist , John / 2008

Uppsala universitet Systematik Och Fylogeni
0971675910 / Link / Owe-Larsson , Björn / 2008

Uppsala universitet Medicin
N/A / Link / Lichtwarck-Aschoff , Michael / 2008

Uppsala universitet Övrigt
N/A / Link / Ahlberg , Per E. / 1999

Uppsala universitet Samhällsvetenskap
N/A / Link / Magnusson , Lena / 2003

N/A / Link / Ahlberg , Per E / 1994

Uppsala universitet Biologi
The tRNALeu (UAA) intron has been recorded in the plastid genome of many algae and land plants and was the first intron to be discovered in cyanobacteria. In all known cases it interrupts the tRNALeu anticodon loop at a conserved position (U-intron-AA). Cyanobacteria are a diverse group of photosynthetic prokaryotes, some involved in symbiotic associations with a wide range of organisms. The most studied associations are those with plants, where strains of Nostoc are the common cyanobacterial partner. In this thesis two aspects of the biology of the cyanobacterial tRNALeu (UAA) intron are focused: first, the use of the intron as a genetic marker for studying the diversity and specificity of two cyanobacterial symbiosis (bryophytes and cycads) and second, the evolutionary patterns of the intron by using the unique data set generated from the diversity analysis.From the studies, many different Nostoc strains are involved in the two symbiotic associations, although no variation was observed within a single bryophyte cavity or cycad coralloid root. Furthermore, a certain level of temporal stability in the cyanobiont composition of the bryophyte population was found and, in the cycad association different coralloid roots from a single specimen may harbor different cyanobacteria. That a minor cyanobiont could have avoided detection is still possible but unlikely. The sequence alignment of the Nostoc tRNALeu (UAA) introns reveals great sequence similarity with size variation only found in the structural element P6b. This element was found to consist of heptanucleotide repeats and of other non-repetitive genetic elements (NIS elements). The sporadic occurrence of the NIS elements indicates recent origins and a mechanism for its dispersal is proposed.In this thesis new insights are given concerning cyanobacterial symbioses and also on the mechanisms involved in the evolution of an old genetic element: the tRNALeu (UAA) intron in cyanobacteria.
91-554-6033-X / Link / Costa , José Luis / 2004

This thesis deals with phylogenetic relationships at different taxonomic levels. All the plants studied are or have been included in the order Gentianales, which comprises about 17 200 species. The phylogenies are based on parsimony analyses of nucleotide sequence data (DNA) from different regions in the chloroplast genome, but morphological characteristics have also been studied.Analyses of sequence data from the genes rbcL and ndhF provide the interfamilial structure of the order Gentianales, shown to comprise the families Apocynaceae (incl. Asclepiadaceae), Gelsemiaceae, Gentianaceae, Loganiaceae, and Rubiaceae. Exclusion of certain genera from the Loganiaceae is confirmed and their phylogenetic positions are clarified. Some of these genera remain within the Gentianales, while others belong to other orders. Exclusion of the tribe Buddlejeae from the Loganiaceae is confirmed, and a monophyletic group formed by Buddleja, Emorya, Gomphostigma, and Nicodemia is recognized and placed in the Lamiales. The Loganiaceae s.str. forms, after these exclusions, a strongly supported monophyletic group comprising 13 genera.The tribe Paederieae in the family Rubiaceae is analysed using sequence data from the regions rbcL gene, rps16 intron, and the regions trnT-F, and is shown to be paraphyletic. These results lead to a new circumscription of Paederieae comprising the genera Leptodermis, Paederia, Serissa, and Spermadictyon. The tribe Putorieae is reestablished with the single genus Plocama, including 34 species. Aitchisonia, Choulettia, Crocyllis, Gaillonia, Jaubertia, Pseudogaillonia, Pterogaillonia, and Putoria are reduced to synonyms of Plocama based on the molecular analyses and morphological studies.The Mediterranean species of the re-circumscribed Plocama, previously segregated as the genus Putoria, are revised. Two species, Plocama calabrica and P. brevifolia, are recognized, their synonymics are established, and seven lectotypes are selected.
91-554-6393-2 / Link / Backlund , Maria / 2005

Evolutionary biology is dependent on accurate phylogenies. In this thesis two branch support methods, Bayesian posterior probablities and bootstrap frequencies, were evaluated with simulated data and empirical data from the chloroplast genome. Bayesian inference was found to be more powerful and less conservative than maximum likelihood bootstrapping, but considerably more sensitive to choice of parameters. Bayesian inference increased in power when data were underparameterized, but the associated increase in type I error was comparatively larger.The chloroplast DNA phylogeny of the tribe Sileneae (Caryophyllaceae) was inferred by analysis of 33,149 aligned nucleotide bases representing 24 taxa. The position of the SW Anatolian taxa Silene cryptoneura and S. sordida strongly disagreed with previous studies on nuclear DNA sequence data, and indicate a possible case of homoploid hybrid origin. Silene atocioides and S. aegyptiaca formed a sister group to Lychnis and remaining Silene, thus suggesting that Silene may be paraphyletic, despite recent revisions based on molecular data. Several nodes in the phylogeny remained poorly supported, despite large amounts of data. Additional sequence sampling is not expected to solve this problem. The main reason for poor resolution is probably a combination of rapid radiation and substitution rate hererogeneity. Apparent incongruent patterns between different regions of the chloroplast genome are evaluated with ancient interspecific chloroplast recombination as explanatory model.Extremely elevated substitution rates in the exons of the plastid clpP gene was documented in Oenothera and three separate lineages of Sileneae. Introns have been lost in some of the lineages, but where present, intron sequences have a markedly slower substitution rate, similar to the rates found in other introns of their genomes. Three branches in the phylogeny show significant whole gene positive selection. In two of the lineages multiple partial copies of the gene were found.
91-554-6668-0 / Link / Erixon , Per / 2006

Uppsala universitet Övrigt
This thesis focuses on phylogenetic, taxonomic, ecological, and conservation aspects of the crustose lichen genus Lecania (Ramalinaceae, lichenized Ascomycota). Lecania has previously been defined on basis of relatively few morphological characters, and the genus had never been treated in molecular phylogenies.The molecular phylogeny of the genus is inferred from DNA sequences. Twenty-five species traditionally placed in Lecania are included in the study along with 21 species from closely related genera. Lecania is a polyphyletic genus. A well-supported monophyletic group containing 16 Lecania species, including the type species L. fuscella is discovered, i.e. Lecania s. str. Nine species formerly included in Lecania do not belong in the genus. A new species, L. belgica, is described.The relationships of a group of morphologically similar Lecania species, i.e. the L. cyrtella group are investigated using morphological and molecular methods. Haplotype network and phylogenetic analyses indicate that the included species, as conceived in the morphological examinations, all are monophyletic. Two new species, L. leprosa and L. madida, are described, L. proteiformis is resurrected from synonymy, and the known range of L. prasinoides is greatly expanded.The type species Lecania fuscella has become endangered in many countries. Twelve localities in Sweden where the species had been found historically are investigated, but L. fuscella is only recovered in one locality. The species composition in these 12 localities, 58 old and 5 new collections with L. fuscella is determined and analyzed. The vegetation community differs between the old and the new collections, and between the locality where the species is recovered and those where it is not. Lecania fuscella has not been able to adapt to environmental changes and now only appears in a specific type of vegetation community. The phylogenetic diversity of the species is calculated, but does not reflect the species’ evolutionary potential.
978-91-554-6953-5 / Link / Reese Næsborg , Rikke / 2007

Uppsala universitet Företagsekonomi
This paper highlights the question of actor identities in business network theory when applied on consumer product markets, which has traditionally tended to polarize industrial - consumer activities and actor identities leaving the consumer activities outside the primary network analysis . Is it perhaps time to rethink the boundaries that are traditionally drawn up between industrial and consumer actors as subjects occupying separate roles, performing interactive but at the same time polarized activities? Previous works of business network theory conducted by the IMP group suggested that the actor identity should be studied as a result of processes in the network, which means that "changes in the network lead to changes in the identities of actors and can even cause new actors to emerge". However, since consumer activities have hitherto been perceived as far too temporary, fragmented and unorganized they have subsequently not been regarded as part of the process. They have consequently not being perceived as a network actor and/or included in the network horizon.Due to the increasing access to, and utilization of, affordable digital hardware/software and escalatingadaptation to internet-based activities there would however seem to be a shift in role performances. Itwould appear that a number of activities are being transferred from the traditional activity sphereswithin business/industries, and taken over by other actor groups. Research conducted within the realm of Consumer Culture Theory (CCT) also indicates that these activities are far but unorganized or merely transaction based. Has the influence of consumer activities in exchange networks with the increasing utilization of digital media and IT altered the identity of the consumer? Does this force us as researchers to consider including these activities when defining the network horizon?
N/A / Link / Gunnlaugsson , Geir / 2008

The focus for the first part of the thesis is on the systematics of species belonging to Silene subgenus Silene. Phylogenetic relationships are inferred from DNA sequences from both the plastid (the rps16 intron) and the nuclear (ITS, intron of the RPB2 gene) genomes. Silene section Rigidulae is shown to be non-monophyletic in its previous circumscription, but instead consisting of six separate clades, each correlated to the geographical distribution of the included species. The taxonomic consequences for each clade are discussed. One of the clades is recognized as a new section and described as Silene sect. Arenosae sect. nov. The morphological descriptions of the species are formalized using a novel implementation of the Prometheus Description Model. Two proposals are included in the thesis, one to reject the name Silene polyphylla L., which is a senior synonym to S. portensis L. Silene linearis Decne. is proposed for conservation against the rarely used S. linearis Sweet.Silene antirrhina, a weedy American annual, is strongly supported as sister to the Hawaiian endemic species of Silene, suggesting an American origin for these. Two of the endemics have evolved woodiness after introduction to Hawaii.In the second part of the thesis we use four nuclear DNA regions, (introns from RPA2, RPB2, RPD2a, RPD2b), and the chloroplast psbE-petG spacer. A framework is developed to evaluate different phylogenetic explanations for conflicting gene trees, where divergence times are used to discriminate among inter- and intralineage processes. The incongruences observed regarding the relationships among the three major lineages of Heliosperma are best explained by homoploid hybridization. The pattern regarding the origin of Heliosperma itself is more complicated and is likely to include several reticulate events. Two lineages have probably been involved in the origin of Heliosperma, one leading to Viscaria and Atocion and the other to Eudianthe and/or Petrocoptis.
91-554-6749-0 / Link / Eggens , Frida / 2006

Uppsala universitet Övrigt
978-87-7289-776-9 / Link / Blanck , Dag / 2002

Uppsala universitet Övrigt
91-7203-938-8 / Link / Blanck , Dag / 2000

Uppsala universitet Arkeologi, Nordeuropeisk
N/A / Link / Kaliff , Anders / 2006

Uppsala universitet Övrigt
Induction of the cytochrome P450(CYP)1A protein and the connected increase in 7-ethoxyresorufin O-deethylase (EROD) activity are common biomarkers in fish. Enhanced activity of this protein signals exposure to Ah-receptor agonists such as chlorinated dioxins, co-planar polychlorinated biphenyls (PCBs) and certain polycyclic aromatic hydrocarbons (PAHs). The EROD biomarker is commonly analyzed in liver microsomes. However, the gill is directly exposed to waterborne pollutants, and in this thesis the gill filament EROD assay was therefore evaluated as a monitoring tool for waterborne CYP1A inducers in fish. Originally developed in rainbow trout (Oncorhynchus mykiss), the assay was here applied in various limnic and marine species. Following exposure to low waterborne concentrations of the readily metabolized CYP1A inducers benzo(a)pyrene (BaP) and indigo, a strong EROD induction was observed in the gill but not in the liver. This likely reflected metabolic clearance of the inducers in gill and other extrahepatic tissues. The high sensitivity of the gill was confirmed in studies of fish caged in waters in urban and rural areas in Sweden where the gill consistently showed a more pronounced EROD induction compared with the liver and the kidney. Fish caged in the reference waters showed surprisingly strong gill EROD induction and CYP1A immunostaining. Consequently, there may be CYP1A inducers present in the aquatic environment that are not yet identified. The assay was further applied in Atlantic cod (Gadus morhua) as a biomarker of exposure to crude oil and produced water (PW) from oil fields in the North Sea. The assay was finally adapted to detect inhibiting compounds, and an imidazole, a triazole and a plant flavonoid turned out to be potent gill EROD inhibitors. The overall conclusion from the studies of this thesis is that the gill filament EROD assay is a practical and sensitive biomarker of exposure to waterborne CYP1A inducers in various fish species. The induction of gill EROD activity in fish also at the reference sites in the field studies calls for further studies on background contamination in Swedish waters.
978-91-554-6902-3 / Link / Abrahamson , Alexandra / 2007

This thesis investigates the neurotoxic effects in mice neonatally co-exposed to different toxic environmental agents during a defined critical period of the brains's rapid growth and development.Environmental toxic agents are incorporated in our environment. The agents investigated in this thesis are ortho-substituted polychlorinated biphenyls (PCBs 52, and 153), co-planar PCB (PCB 126), polybrominated diphenyl ether (PBDE 99), methyl mercury (MeHg), and γ-radiation. Several epidemiological studies show that human exposure to environmental agents during early development can affect childhood cognitive development.The brain growth spurt (BGS) is defined by rapid growth and development of the immature brain. For rodents (rats and mice) the BGS is postnatal spanning the first 3-4 weeks after birth. For humans this period begins during the third trimester of pregnancy and continues throughout the first two years of life. Several studies have shown that the BGS period of the brain's development renders the brain vunerable and susceptible to insults caused by environmental agents.The combinations of environmental agents used in this thesis were: PCB 52 + PBDE 99, PCB 153 + MeHg, PCB 126 + MeHg, PBDE 99 + MeHg, and γ-radiation + MeHg. The studies presented in this thesis show that co-exposure to low doses of environmental agents lead to interaction effects. These effects of interaction include defective spontaneous behavior, diminished habituation capabilities and hyperactive condition, decreased learning and memory abilities, and reduction in the nicotinic cholinergic receptor densities.Traditionally environmental agents are evaluated one at a time to investigate their effects of toxicity. This thesis indicates that the effects of interaction caused by co-exposure were often seen at doses where exposure to the individual environmental agent alone did not cause any effect. The observed effect of co-exposure were often as pronounced as a dose up to ten times the individual environmental agent alone.
978-91-554-7071-5 / Link / Fischer , Celia / 2008

Uppsala universitet Företagsekonomi
I denna forskningsrapport redovisas övergripande lärdomar och tankegångar från ett fyraårigt forskningsprojekt med titeln ”Ett kunskapsperspektiv på organisation och ledarskap – studier av kunskapsprocesser och kunskapsledarskap för innovation och förnyelse”. Projektet har varit finansierat av Vinnova, Verket för Innovationssystem.Inom projektets ram har en serie kunskapsintensiva organisationer och företag studerats, som har det gemensamt att de befunnit sig i skeden av innovation och/eller mer genomgripande förändring. Tanken med att följa organisationer i sådana skeden är att behovet av att skapa förutsättningar för lärande och nyutveckling av kunskap ställs på sin spets, och ledarskap och organisering som främjar kunskapsutveckling blir särskilt viktigt. Hur lärandeklimat, förändringsarbete och ledarskap i innovationsmiljöer ser ut och kan utvecklas är ett genomgående tema i studierna (vilka finns separat publicerade i en serie forskningsrapporter) .De övergripande teman från projektet som lyfts fram och diskuteras i denna rapport är:• Om kunskapsintensiva organisationer och kunskapsarbete. Vad är kunskapsarbete och kunskapsintensiva organisationer? Hur tänker kunskapsarbetare, och varför behövs det ett tydligare ”språk” för kunskapande arbetsformer?• Om det osynliga kunnandet – organisationens värdefullaste resurs? Här diskuteras det personliga, osynliga kunnandet, som också innehåller en stor potential för lärande och innovationer. I avsnittet diskuteras även förutsättningarna för att ta vara på och vidareutveckla det osynliga kunnandet. Hur lyfter man fram kunskap som inte är formaliserad och faktaburen? Hur synliggör man kunskap som inte syns?• På spaning efter kunskapens ledarskap. Ledarskapets roll i kunskapsintensiva organisationer diskuteras. I studierna har vi observerat att en speciell aspekt av ledarskapet behöver förstärkas – det horisontella, integrerande ledarskapet, som kan verka tvärs över formella och professionella strukturer. Hur kan ett sådant integrerande ledarskap främjas?• På väg mot en kunskapens ekologi. I detta avsnitt diskuteras med utblick i internationell forskning om positiv organisationspsykologi lärandeklimatets betydelse, och vilken roll som tillit, förtroende och mänskliga relationer spelar för kunskapsutveckling i organisationer. Om kunskapande aktiviteter är beroende av sin omgivning och sin miljö – vad kan vi lära om hur att skapa en jordmån för lärande som fokuserar på samspelet mellan människor?
N/A / Link / Södergren , Birgitta / 2008

Uppsala universitet Övrigt
N/A / Link / Eliasson , Jonas /

Cidofovir (HPMPC, 1), a broad-spectrum antiviral agent, is currently used to treat AIDS-related human cytomegalovirus (HCMV) retinitis and has recognized therapeutic potential for orthopox virus infections, but is limited by its low oral bioavailability. Cyclic cidofovir (2) displays decreased nephrotoxicity compared to 1, while also exhibiting potent antiviral activity. Here we describe in detail the synthesis and evaluation as prodrugs of four cHPMPC dipeptide conjugates in which the free POH of 2 is esterified by the Ser side chain alcohol group of an X-L-Ser(OMe) dipeptide: 3 (X=L-Ala), 4 (X=L-Val), 5 (X=L-Leu), and 6 (X=L-Phe). Perfusion studies in the rat establish that the mesenteric permeability to 4 is more than 20-fold greater than to 1, and the bioavailability of 4 is increased 6-fold relative to 1 in an in vivo murine model. In gastrointestinal and liver homogenates, the cHPMPC prodrugs are rapidly hydrolyzed to 2. Prodrugs 3, 4, and 5 are nontoxic at 100 microM in HFF and KB cells and in cell-based plaque reduction assays had IC 50 values of 0.1-0.5 microM for HCMV and 10 microM for two orthopox viruses (vaccinia and cowpox). The enhanced transport properties of 3-6, conferred by incorporation of a biologically benign dipeptide moiety, and the facile cleavage of the Ser-O-P linkage suggest that these prodrugs represent a promising new approach to enhancing the bioavailability of 2.
N/A / Link / Eriksson , Ulrika / 2008