71 research outputs found
Infusion fluids contain harmful glucose degradation products
PURPOSE: Glucose degradation products (GDPs) are precursors of advanced glycation end products (AGEs) that cause cellular damage and inflammation. We examined the content of GDPs in commercially available glucose-containing infusion fluids and investigated whether GDPs are found in patients' blood. METHODS: The content of GDPs was examined in infusion fluids by high-performance liquid chromatography (HPLC) analysis. To investigate whether GDPs also are found in patients, we included 11 patients who received glucose fluids (standard group) during and after their surgery and 11 control patients receiving buffered saline (control group). Blood samples were analyzed for GDP content and carboxymethyllysine (CML), as a measure of AGE formation. The influence of heat-sterilized fluids on cell viability and cell function upon infection was investigated. RESULTS: All investigated fluids contained high concentrations of GDPs, such as 3-deoxyglucosone (3-DG). Serum concentration of 3-DG increased rapidly by a factor of eight in patients receiving standard therapy. Serum CML levels increased significantly and showed linear correlation with the amount of infused 3-DG. There was no increase in serum 3-DG or CML concentrations in the control group. The concentration of GDPs in most of the tested fluids damaged neutrophils, reducing their cytokine secretion, and inhibited microbial killing. CONCLUSIONS: These findings indicate that normal standard fluid therapy involves unwanted infusion of GDPs. Reduction of the content of GDPs in commonly used infusion fluids may improve cell function, and possibly also organ function, in intensive-care patients
Whole-Gene Positive Selection, Elevated Synonymous Substitution Rates, Duplication, and Indel Evolution of the Chloroplast clpP1 Gene
Synonymous DNA substitution rates in the plant chloroplast genome are generally relatively slow and lineage dependent. Non-synonymous rates are usually even slower due to purifying selection acting on the genes. Positive selection is expected to speed up non-synonymous substitution rates, whereas synonymous rates are expected to be unaffected. Until recently, positive selection has seldom been observed in chloroplast genes, and large-scale structural rearrangements leading to gene duplications are hitherto supposed to be rare. genes experiencing negative (purifying) selection are characterized by having very conserved lengths, genes under positive selection often have large insertions of more or less repetitive amino acid sequence motifs. gene and surrounding regions, repetitive amino acid sequences, and increase in synonymous substitution rates. The present study sheds light on the controversial issue of whether negative or positive selection is to be expected after gene duplications by providing evidence for the latter alternative. The observed increase in synonymous substitution rates in some of the lineages indicates that the detection of positive selection may be obscured under such circumstances. Future studies are required to explore the functional significance of the large inserted repeated amino acid motifs, as well as the possibility that synonymous substitution rates may be affected by positive selection
Phylogenetic Support and Chloroplast Genome Evolution in Sileneae (Caryophyllaceae)
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
Extended writing demands : a tool för 'academic drift' and the professionalisation of early childhood profession?
This study explores the extended demands for writing in the Swedish public service sector of early childhood and how academic writing in the higher education programmes aimed at professional work in that sector is perceived to be of value for early childhood practice among practitioners. Empirical data was collected in individual interviews and focus groups among 69 early childhood staff in two different communities. The study points to an overall focus on assessments and evaluation in professional writing which tends to challenge everyday communication, i.e. everyday discourse for an internal audience (staff, parents and children). The study further indicates that professional writing holds implications for social relations and contributes to strengthened hierarchies among early childhood staff; younger generations more trained in academic writing tend to be ârankedâ higher than staff more experienced in practice. Whether the twin demands for âprofessionalâ and âacademicâ writing will contribute to a âprofessionalâ early childhood staff community, as suggested in policy and teacher union rhetoric, remains an open question. Kampen om texte
The degree project in Swedish Early Childhood Education and Care : what is at stake?
This study deals with the undergraduate degree project in teacher training programmes for early childhood education and care in Sweden. For the study we draw on documents and qualitative interviews with teacher educators of different disciplinary backgrounds. The aims of this study were to identify discourses on the degree project in the field of early childhood education and care: (1) in documents; and (2) among teacher educators. Our study points to the tensions between discourses on the degree project as being of primary relevance for the vocational field, or as preparation for research activities. It also shows that varying perceptions on the degree project among teacher educators are largely related to different disciplinary fields. It further emerges that teacher educators have different views about text norms for the degree project, based on different underlying epistemologies to which the student teachers must adapt. We conclude that the multiple and often contradictory requirements of the degree project need critical examination and be reviewed. We also suggest an opening up for new and more creative ways of dealing with the degree project, with greater recognition of professional values and knowledges in the field.Kampen om texten (2012-2015
ECEC studentsâ writing trajectories : academic discourse and "Professional Habitus"
In Sweden and many other countries, the academisation of teacher education goes along with increased emphasis on a student thesis, in Sweden formally entitled the final degree project. This study deals with studentsâ writing trajectories in Early Childhood Education and Care aimed at work in the preschool or the recreation centre. The study indicates that student writing, shaped by a variety of academic literacies, is primarily based on values of the vocational field, parallel to an emerging critical academic approach. The study suggests that academic writing is largely perceived among the students as a means to underpin the vocational field with theory, and see critical thinking and reflective practice as relevant to their future career
The degree project in Swedish Early Childhood Education and Care : what is at stake?
This study deals with the undergraduate degree project in teacher training programmes for early childhood education and care in Sweden. For the study we draw on documents and qualitative interviews with teacher educators of different disciplinary backgrounds. The aims of this study were to identify discourses on the degree project in the field of early childhood education and care: (1) in documents; and (2) among teacher educators. Our study points to the tensions between discourses on the degree project as being of primary relevance for the vocational field, or as preparation for research activities. It also shows that varying perceptions on the degree project among teacher educators are largely related to different disciplinary fields. It further emerges that teacher educators have different views about text norms for the degree project, based on different underlying epistemologies to which the student teachers must adapt. We conclude that the multiple and often contradictory requirements of the degree project need critical examination and be reviewed. We also suggest an opening up for new and more creative ways of dealing with the degree project, with greater recognition of professional values and knowledges in the field.Kampen om texten (2012-2015
School subjects in the screen culture
SkolÀmnesparadigm och undervisningspraktik i skÀrmkulture
From Texts to Pictures in Teaching Civics. Participant Observation in Markâs Classroom
We are now living in a ânew media ageâ, with a dramatic shift from the linguistic to the visual, from books and book pages to screens and windows (Kress, 2003). This article offsets out to explore what happens to educational activities in schools when electronic media and pictures replace written texts. The article draws on interviews and classroom observations of a particular Swedish vocational upper secondary programme, where the social studies teacher observes that students are finding it increasingly difficult to benefit from written texts. Theoretically, the study draws on Meyrowitz (1985/1986) theories concerning the relationship among media, situations and behaviour and the effect of a shift from âprint situationsâ to âelectronic situationsâ on a broad range of social role and Bernsteinâs (1996/2000) notions of ârecontextualisationâ, âframingâ and âclassificationâ. The study shows that classroom relations are changing; hierarchies between students and teachers are being broken down, and classification of subjects is affected in the sense that the studentsâ own interpretations and references are beginning to govern teaching when pictures and electronic media enter the educational discourse
Svenskdidaktikens hÄg för ungdoms- och mediekulturer
Vilken inriktning har den forskning som bedrivs inom det svenskdidaktiska fĂ€ltet? Vilken betydelse har det faktum att vi nu lever i en vĂ€rld som i hög grad förmedlas via visualiÂseringar av olika slag pĂ„ en skĂ€rm nĂ€r nya forskningsfrĂ„gor formuleras? Redan för tjugo Ă„r sedan Ă€gnades i LĂ€roplanskommittĂ©ns betĂ€nkande Skola för bildning (SOU 1992:94) stort utrymme Ă„t skolans relation till medieÂutvecklingen och omvĂ€rldsförĂ€ndringarna. Man menade att det var viktigt att ta elevernas intresse för medievĂ€rlden pĂ„ allvar. UngefĂ€r samtidigt, dvs. i skiftet 1980- och 1990-tal, konsoliderades ocksĂ„ stora delar av forskningen och grundutbildningen inom medieomrĂ„det i egna Ă€mnesinstitutioner eller Ă€mnesavdelningar i det som blev medie- och kommunikationsvetenskap (MKV) (HSV 2001). Den forskning som utvecklades inom det nya Ă€mnet var förbunden, inte bara med utvecklingen inom forskningsdiscipliner som beteendeÂvetenskap, statsvetenskap, ekonomisk historia, konstvetenskap och filosofi, utan ocksĂ„ sprĂ„k- och litteraturvetenskap, dvs. Ă€mnen historiskt nĂ€ra förbundna med utbildningen av lĂ€rare i skolĂ€mnet svenska och dĂ€rmed ocksĂ„ forskningen inom det svenskdidaktiska fĂ€ltet. Medieforskningen Ă€r liksom mĂ„nga and vetenskapliga discipliner dessvĂ€rre mĂ„ttligt intresserad av fĂ€ltet pedagogik, menar Thavenius (1995), som diskuterar mediepedagogikens nuvarande och möjliga roll i skolan. Han identifierar tvĂ„ förhĂ€rskande mediediskurser kopplade till skola och undervisning: den ena gĂ€ller historien om mediernas farlighet, som innebĂ€r att mediekompetens (media literacy) definieras som en förmĂ„ga att skydda sig mot nĂ„got som samhĂ€llet inte kan göra sĂ„ mycket Ă„t, den andra att mediepedagogiken formats av en snĂ€v syn pĂ„ vad undervisning kan vara och vad medievetenskap Ă€r för nĂ„got. Mediepedagogiken riskerar dĂ€rför att bli ett endimensionellt inslag i skolans kulturella produktion, menar han. PĂ„ motsvarande sĂ€tt menar Rönnberg (2003) att skolan underlĂ„ter att anknyta till elevernas medieerfarenheter och att den koncentrerar sig ensidigt pĂ„ skriftligt tillĂ€gnande och struntar medvetet i kommunikationen via och kring medier och andra sprĂ„k Ă€n de rent verbala. Hon argumenterar dĂ€rför för införandet av Ă€mnet âMediepedagogikâ i den svenska skolan och formulerar ett vidgat och internationellt förankrat perspektiv pĂ„ lĂ€s- och skrivinlĂ€rning, medier och kommunikation. Skolan mĂ„ste, menar hon, ta till vara elevernas vardagserfarenheter och fritidskunskaper och anknyta till deras lĂ€roprocesser utanför skolan; det gĂ€ller att försöka begripa vardagskulturen. Det hĂ€r kapitlet handlar om den forskning som vuxit fram inom det svenskdidaktiska fĂ€ltet under de senaste tvĂ„ decennierna. Fonden utgörs av den forskning som lĂ€nge bedrivits inom ett mer lösligt sammansatt forskningsfĂ€lt kring svenskdidaktiska frĂ„gor och som huvudsakligen varit förbundna med lĂ€sning av böcker (codex) och skrivning för hand. Specifikt behandlar kapitlet hur svenskdidaktiken, hĂ€r sedan ungefĂ€r tio Ă„r tillbaka i tiden betraktat som ett mer sammanhĂ„llet forskningsfĂ€lt, intresserar sig för och förhĂ„ller sig till modern teknologi och dess relation till ungdomskulturer. Intresset Ă€r sĂ„ledes inte enbart riktat mot datorn som ett hjĂ€lpmedel, utan ny teknologi knutet till ungdomskultur och elevers erfarenheter. Teoretiskt utgĂ„r jag frĂ„n ett medieekologiskt perspektiv, vilket bland annat innebĂ€r att jag betraktar institutionen skola och den tillhörande undervisningen i svenska som historiskt och symbiotiskt förbunden inte bara med kyrka, lĂ€s- och skrivundervisning (Erixon 2010; Johansson 1977; Tyner 1998), utan ocksĂ„ med teknologierna bok, papper och penna
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