276 research outputs found

    Dialogue as a Journalistic Ideal

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    Discussions and practices related to participatory and interactive journalism emphasize the dialogical aspects of journalism. However, throughout history, the idea of dialogue in journalism has taken a variety of forms. This paper places dialogue as a journalistic ideal under scrutiny. Our aim is twofold: first, we map out the development and different functions of the ideal in some decisive eras in the history of journalism and in the current context of digital journalism; second, we present a model of how to best capture and understand the significance of dialogue to contemporary journalism. The model is based on an exploration of philosophical preconditions for dialogue as an ideal in journalism. We will also look at the significance of dialogue in different genres and in interactive dimensions of journalism

    Verdal videregående skole sin ”reise” mot å bli en mer lærende organisasjon - Hvor er vi? og Hvor vil vi?

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    Temaet er den lærende organisasjon, og problemstillingen er knyttet til Verdal vgs. sin reise mot å bli en mer lærende organisasjon. Reisen har vært sammen med skolens mellomledergruppe, som består av område- og seksjonslederne. Det første forskningsspørsmålet handler om hva er Verdal videregående skole sin status i arbeidet med St. meld. nr. 30 (2003-2004) Kultur for læring og som lærende organisasjon. Det andre forskningsspørsmålet handler om hvilke valg kan bidra til å utvikle Verdal videregående skole til en mer lærende organisasjon. Det siste forskningsspørsmålet handler om hvilke utfordringer teoretisk og praktisk har vi møtt på ”vår reise” mot en mer lærende organisasjon. Forfatteren drøfter underveis fordeler og ulemper ved å forske på egen arbeidsplass knyttet til egen forutforståelse, dobbeltrolle og tilgang til feltet. Han har valgt aksjonsforskning som metode

    A modular field system for near-surface, vertical profiling of the atmospheric composition in harsh environments using cavity ring-down spectroscopy

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    Cavity ring-down spectroscopy (CRDS) has allowed for increasingly widespread, in situ observations of trace gases, including the stable isotopic composition of water vapor. However, gathering observations in harsh environments still poses challenges, particularly in regard to observing the small-scale exchanges taking place between the surface and atmosphere. It is especially important to resolve the vertical structure of these processes. We have designed the ISE-CUBE system as a modular CRDS deployment system for profiling stable water isotopes in the surface layer, specifically the lowermost 2 m above the surface. We tested the system during a 2-week field campaign during February–March 2020 in Ny-Ålesund, Svalbard, Norway, with ambient temperatures down to −30 ∘C. The system functioned suitably throughout the campaign, with field periods exhibiting only a marginal increase in isotopic measurement uncertainty (30 %) as compared to optimal laboratory operation. Over the 2 m profiling range, we have been able to measure and resolve gradients on the temporal and spatial scales needed in an Arctic environment.publishedVersio

    Non-Equilibrium Fractionation Factors for D/H and 18O/16O During Oceanic Evaporation in the North-West Atlantic Region

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    Ocean isotopic evaporation models, such as the Craig-Gordon model, rely on the description of nonequilibrium fractionation factors that are, in general, poorly constrained. To date, only a few gradient-diffusion type measurements have been performed in ocean settings to test the validity of the commonly used parametrization of nonequilibrium isotopic fractionation during ocean evaporation. In this work, we present 6 months of water vapor isotopic observations collected from a meteorological tower located in the northwest Atlantic Ocean (Bermuda) with the objective of estimating nonequilibrium fractionation factors (k, ‰) for ocean evaporation and their wind speed dependency. The Keeling Plot method and Craig-Gordon model combination were sensitive enough to resolve nonequilibrium fractionation factors during evaporation resulting into mean values of k18 = 5.2 ± 0.6‰ and k2 = 4.3 ± 3.4‰. Furthermore, we evaluate the relationship between k and 10-m wind speed over the ocean. Such a relationship is expected from current evaporation theory and from laboratory experiments made in the 1970s, but observational evidence is lacking. We show that (a) in the observed wind speed range [0–10 m s−1], the sensitivity of k to wind speed is small, in the order of −0.2‰ m−1 s for k18, and (b) there is no empirical evidence for the presence of a discontinuity between smooth and rough wind speed regime during isotopic fractionation, as proposed in earlier studies. The water vapor d-excess variability predicted under the closure assumption using the k values estimated in this study is in agreement with observations over the Atlantic Ocean.publishedVersio

    Tras los pasos de los exploradores polares

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    Tidewater glaciers as “climate refugia” for zooplankton-dependent food web in Kongsfjorden, Svalbard

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    With climate warming, many tidewater glaciers are retreating. Fresh, sediment-rich sub-glacial meltwater is discharged at the glacier grounding line, where it mixes with deep marine water resulting in an upwelling of a plume visible in front of the glacial wall. Zooplankton may suffer increased mortality within the plume due to osmotic shock when brought in contact with the rising meltwater. The constant replenishment of zooplankton and juvenile fish to the surface areas attracts surface-foraging seabirds. Because access to other feeding areas, such as the marginal ice zone, has become energetically costly due to reduced sea-ice extent, glacial plumes may become increasingly important as “climate refugia” providing enhanced prey availability. Here, we investigated zooplankton concentrations within the plume and adjacent waters of four tidewater glaciers in Kongsfjorden, Svalbard, in early August 2016 and late July 2017. Our aim was to compare the zooplankton composition, abundance, and isotopic signatures within the plumes to those in adjacent fjord and shelf waters. Our hypothesis was that the plumes resulted in increased zooplankton mortality through osmotic shock and increased prey availability to predators. The mortality due to osmotic shock in the glacial plume was low (<5% dead organisms in samples), although slightly higher than in surrounding waters. This indicates that plumes are inefficient “death traps” for zooplankton. However, the high abundance and biomass of zooplankton within plume areas suggest that the “elevator effect” of rising glacial water supplies zooplankton to the sea surface, thereby enhancing prey availability for surface-feeding seabirds. Thus, our study provides evidence that glacial plumes are important as “climate refugia” for foraging seabirds. Stable isotope signatures showed that the glacial bay zooplankton and fish community represent a distinct isotopic niche. Additionally, zooplankton mortality associated with the plume estimated over 100-days of melt season supports a flux of 12.8 tonnes of organic carbon to benthic communities in the glacial bays. Benthic scavengers, such as Onisimus caricus and Anonyx nugax, were abundant in the glacial bay, where they feed on sinking organic matter.publishedVersio

    Gene expression profiles in rat brain disclose CNS signature genes and regional patterns of functional specialisation

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    Background: The mammalian brain is divided into distinct regions with structural and neurophysiological differences. As a result, gene expression is likely to vary between regions in relation to their cellular composition and neuronal function. In order to improve our knowledge and understanding of regional patterns of gene expression in the CNS, we have generated a global map of gene expression in selected regions of the adult rat brain (frontomedial-, temporal- and occipital cortex, hippocampus, striatum and cerebellum; both right and left sides) as well as in three major non-neural tissues (spleen, liver and kidney) using the Applied Biosystems Rat Genome Survey Microarray. Results: By unsupervised hierarchical clustering, we found that the transcriptome within a region was highly conserved among individual rats and that there were no systematic differences between the two hemispheres (right versus left side). Further, we identified distinct sets of genes showing significant regional enrichment. Functional annotation of each of these gene sets clearly reflected several important physiological features of the region in question, including synaptic transmission within the cortex, neurogenesis in hippocampus and G-protein-mediated signalling in striatum. In addition, we were able to reveal potentially new regional features, such as mRNA transcription- and neurogenesis-annotated activities in cerebellum and differential use of glutamate signalling between regions. Finally, we determined a set of 'CNSsignature' genes that uncover characteristics of several common neuronal processes in the CNS, with marked overrepresentation of specific features of synaptic transmission, ion transport and cell communication, as well as numerous novel unclassified genes. Conclusion: We have generated a global map of gene expression in the rat brain and used this to determine functional processes and pathways that have a regional preference or ubiquitous distribution within the CNS, respectively. The existence of shared specialised neuronal activities in CNS is interesting in a context of potential functional redundancy, and future studies should further explore the overall characteristics of CNS-specific versus region-specific gene profiles in the brain
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