Kunnskapsdeling mellom lærere. En kvalitativ studie med fokus på hvordan lærere erfarer kunnskapsdeling i profesjonsfellesskapet

Masteroppgave i tilpassa opplæring - 201

Reconstruction of former glacier equilibrium-line altitudes based on proglacial sites: an evaluation of approaches and selection of sites

Various approaches are used to record variations in glacier activity and equilibrium-line altitudes (ELAs) based on proglacial sites (lacustrine and terrestrial). These approaches are based on a conceptual model of glacier-meltwater induced sedimentation in which the minerogenic (nonorganic) component of the sediments is related to the occurrence of a glacier in the catchment. The principal coupling to former glacier activity and ELAs is common for these approaches. However, different methods and techniques may complement each other, and both possibilities and limitations are demonstrated. Site selection for reconstructing variations in glacier activity/ELAs is evaluated and critical factors are discussed. Rerouting of glacier meltwater streams across local watersheds in combination with proglacial sites gives a distinct on/off signal for former glacier activity/ELAs. Together with representative lateral moraines of known age, local watersheds are important for calibrating reconstructed glacier activity/ELAs based on a chain of proglacial lakes. Based on the ‘modern analogue principle’, various proxies can record whenever glaciers existed in a catchment. In a chain of proglacial lakes with different sensitivity to record variations in glacier activity/ELAs, these proxies can be calibrated against independent records. For one-site approaches, however, variations in glacier activity/ELAs depend on the interpretation and sensitivity of the proxies used

Long‑term demise of sub‑Antarctic glaciers modulated by the Southern Hemisphere Westerlies

The accelerated melting of ice on the Antarctic Peninsula and islands in the sub-Antarctic suggests that the cryosphere is edging towards an irreversible tipping point. How unusual is this trend of ice loss within the frame of natural variability, and to what extent can it be explained by underlying climate dynamics? Here, we present new high-resolution reconstructions of long-term changes in the extents of three glaciers on the island of South Georgia (54°S, 36°W), combining detailed analyses of glacial-derived sediments deposited in distal glacier-fed lakes and cosmogenic exposure dating of moraines. We document that the glaciers of South Georgia have gradually retracted since the Antarctic cold reversal (ACR, 14.5–12.8 ka), culminating in the disappearance of at least one of the reconstructed glaciers. The glacier retreat pattern observed in South Georgia suggests a persistent link to summer insolation at 55°S, which intensified during the period from the ACR to approximately 2 ka. It also reveals multi-decadal to centennial climate shifts superimposed on this long-term trend that have resulted in at least nine glacier readvances during the last 10.5 ka. Accompanying meridional changes in the Southern Hemisphere westerlies and their interconnection with local topography may explain these glacier readvances.publishedVersio

Holocene palaeoclimate reconstructions at Vanndalsvatnet, western Norway, with particular reference to the 8200 cal. yr BP event

Analyses of organic content, magnetic susceptibility, grain size and pollen in sediments from the proglacial lake Vanndalsvatnet in western Norway provide a high-resolution terrestrial record and pollenbased quantitative estimates of mean July and January temperatures and annual precipitation across the /8200 cal. yr BP event. Glaciers in the catchment melted away at approximately 8600 cal. yr BP. Immediately following deglaciation, a series of thin minerogenic layers indicate several abrupt, short-lived glacial episodes peaking at /8550, 8450, 8350, 8250, 8200, 7900, 7300 and 7150 cal. yr BP. A single, mid- Holocene glacial episode occurred at 4900 4800 cal. yr BP. Between 2000 and 1400 cal. yr BP, six shortlived glacial episodes occurred /2000, 1900, 1800, 1700, 1600, and 1500 cal. yr BP. The part of Spørteggbreen that drains to Vanndalsvatnet has existed continuously since /1400 cal. yr BP. Just prior to a first loss-on-ignition minimum reflecting a glacial episode centred at 8200 cal. yr BP, pollen-inferred July temperatures were relatively high, January temperatures were low, and annual precipitation was relatively low. During the period 8200 7900 cal. yr BP, July temperatures showed a falling trend. Both January temperature and annual precipitation, however, were relatively high. After 7900 cal. yr BP, July temperatures increased, but both January temperatures and annual precipitation were lower than in the preceding period. The pollen analytical and sedimentary data suggest that the glacial advance during the Finse event seems not to have been a response to cooler summers, but to milder winters and increasing precipitation (similar to a positive North Atlantic Oscillation weather mode)

Repeated bronchoscopy in health and obstructive lung disease: is the airway microbiome stable?

Objective Little is known concerning the stability of the lower airway microbiome. We have compared the microbiota identified by repeated bronchoscopy in healthy subjects and patients with ostructive lung diseaseases (OLD). Methods 21 healthy controls and 41 patients with OLD completed two bronchoscopies. In addition to negative controls (NCS) and oral wash (OW) samples, we gathered protected bronchoalveolar lavage in two fractions (PBAL1 and PBAL2) and protected specimen brushes (PSB). After DNA extraction, we amplified the V3V4 region of the 16S rRNA gene, and performed paired-end sequencing (Illumina MiSeq). Initial bioinformatic processing was carried out in the QIIME-2 pipeline, identifying amplicon sequence variants (ASVs) with the DADA2 algorithm. Potentially contaminating ASVs were identified and removed using the decontam package in R and the sequenced NCS. Results A final table of 551 ASVs consisted of 19 × 106 sequences. Alpha diversity was lower in the second exam for OW samples, and borderline lower for PBAL1, with larger differences in subjects not having received intercurrent antibiotics. Permutational tests of beta diversity indicated that within-individual changes were significantly lower than between-individual changes. A non-parametric trend test showed that differences in composition between the two exams (beta diversity) were largest in the PSBs, and that these differences followed a pattern of PSB > PBAL2 > PBAL1 > OW. Time between procedures was not associated with increased diversity. Conclusion The airways microbiota varied between examinations. However, there is compositional microbiota stability within a person, beyond that of chance, supporting the notion of a transient airways microbiota with a possibly more stable individual core microbiome.publishedVersio

A longitudinal follow-up of autoimmune polyendocrine syndrome type 1

Source:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4971337/Context: Autoimmune polyendocrine syndrome type 1 (APS1) is a childhood-onset monogenic disease defined by the presence of two of the three major components: hypoparathyroidism, primary adrenocortical insuffi- ciency, and chronic mucocutaneous candidiasis (CMC). Information on longitudinal follow-up of APS1 is sparse. Objective: To describe the phenotypes of APS1 and correlate the clinical features with autoantibody profiles and autoimmune regulator ( AIRE) mutations during extended follow-up (1996–2016). Patients: All known Norwegian patients with APS1. Results: Fifty-two patients from 34 families were identified. The majority presented with one of the major disease components during childhood. Enamel hypoplasia, hypoparathyroidism, and CMC were the most frequent compo- nents.Withage,mostpatientspresentedthreetofivediseasemanifestations,althoughsomehadmilderphenotypes diagnosed in adulthood. Fifteen of the patients died during follow-up (median age at death, 34 years) or were deceasedsiblingswithahighprobabilityofundisclosedAPS1.Allexceptthreehadinterferon- )autoantibodies,and allhadorgan-specificautoantibodies.Themostcommon AIRE mutationwasc.967_979del13,foundinhomozygosity in 15 patients. A mild phenotype was associated with the splice mutation c.879 1G A. Primary adrenocortical insufficiency and type 1 diabetes were associated with protective human leucocyte antigen genotypes. Conclusions: Multiple presumable autoimmune manifestations, in particular hypoparathyroidism, CMC, and enamel hypoplasia, should prompt further diagnostic workup using autoantibody analyses (eg, interferon- ) and AIRE sequencing to reveal APS1, even in adults. Treatment is complicated, and mortality is high. Structured follow-up should be performed in a specialized center

AIRE-genets rolle i revmatoid artritt

Introduksjon: Revmatoid artritt (RA) er en systemisk autoimmun sykdom som hovedsakelig påvirker ledd. RA er assosiert med flere antistoffer, deriblant revmatoid faktor (RF) og anti-citrullinert protein-antistoff (ACPA). Det er gjort mye forskning med mål å finne årsaksfaktorer til sykdommen, med det er fortsatt mye en ikke vet. Genet AIRE (autoimmune regulator) har blitt identifisert som en genetisk risikofaktor for RA. Målet med denne studien er å undersøke det genetiske bidraget til RA-risiko for fire enkeltnukleotidpolymorfismer (engelsk: Single Nucleotide Polymorphisms, SNP-er) på AIRE-genet i norsk befolkning. Metode: 935 pasienter og 1111 kontroller ble inkludert i denne studien. Deltakerne ble genotypet ved hjelp av TaqMan alleldiskrimineringsassays for å bestemme hver deltakeres alleler av fire ulike SNP-er på AIRE-genet: rs878081, rs2075876, rs3788113 og rs760426. Alle genotyper og alle teoretisk mulige haplotyper av to, tre og fire SNP-er ble også undersøkt. Pasienter ble undersøkt i tre grupper: alle pasienter sammen, kun ACPA-positive pasienter og kun ACPA-negative pasienter. Resultater: rs878081 og rs2075876 viste ingen statistisk signifikant forskjell i allelfordeling mellom pasienter og kontroller. For rs3788113 viste det vanligste allelet (major-allelet (A-allelt)) seg å være assosiert med økt risiko for RA, OR=1,22 (95% KI 1,05-1,42; p=0,0116). Også for rs760426 viste det vanligste allelet (A-allelet) seg å være assosiert med økt risiko for RA, OR=1,33 (95% KI 1,10-1,61; p=0,0030). Konklusjon: Disse resultatene tyder på at AIRE-genet er assosiert med RA i norsk befolkning. Ved sammenlikning med andre publiserte studier ser en at hvilke SNP-er som er assosiert med RA og hvilken assosiasjon dette er varierer mellom populasjoner