Fant 9888 publikasjoner. Viser side 290 av 396:
Effects of titanium dioxide nanoparticles on the Hprt gene mutations in V79 hamster cells
The genotoxicity of anatase/rutile TiO2 nanoparticles (TiO2 NPs, NM105 at 3, 15 and 75 µg/cm2) was assessed with the mammalian in-vitro Hypoxanthine guanine phosphoribosyl transferase (Hprt) gene mutation test in Chinese hamster lung (V79) fibroblasts after 24 h exposure. Two dispersion procedures giving different size distribution and dispersion stability were used to investigate whether the effects of TiO2 NPs depend on the state of agglomeration. TiO2 NPs were fully characterised in the previous European FP7 projects NanoTEST and NanoREG2. Uptake of TiO2 NPs was measured by transmission electron microscopy (TEM). TiO2 NPs were found in cytoplasmic vesicles, as well as close to the nucleus. The internalisation of TiO2 NPs did not depend on the state of agglomeration and dispersion used. The cytotoxicity of TiO2 NPs was measured by determining both the relative growth activity (RGA) and the plating efficiency (PE). There were no substantial effects of exposure time (24, 48 and 72 h), although a tendency to lower RGA at longer exposure was observed. No significant difference in PE values and no increases in the Hprt gene mutant frequency were found in exposed relative to unexposed cultures in spite of evidence of uptake of NPs by cells.
MDPI
2020
2025
2020
2014
Effects of rocket launches in Ny-Ålesund, 2018 - 2019. Observations of snow and air samples.
The report summarizes the results from additional snow sampling and regular monitoring activities in connection to the rocket launch in Ny-Ålesund 7 Dec 2018, 26 Nov 2019 and 10 Dec 2019 to document possible impacts on environment and on the monitoring activities in Ny-Ålesund. An enhanced deposition of aluminium (Al) and iron (Fe) on the local environment due to the rocket launch is observed.
NILU
2021
2010
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2018
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2009
Effects of increased biomass removal on the biogeochemistry of two Norwegian forest ecosystems. NILU PP
2009
2019
2019
The effect of the 2018 extreme meteorological conditions in Europe on methane (CH4) emissions is examined using estimates from four atmospheric inversions calculated for the period 2005–2018. For most of Europe, we find no anomaly in 2018 compared to the 2005–2018 mean. However, we find a positive anomaly for the Netherlands in April, which coincided with positive temperature and soil moisture anomalies suggesting an increase in biogenic sources. We also find a negative anomaly for the Netherlands for September–October, which coincided with a negative anomaly in soil moisture, suggesting a decrease in soil sources. In addition, we find a positive anomaly for Serbia in spring, summer and autumn, which coincided with increases in temperature and soil moisture, again suggestive of changes in biogenic sources, and the annual emission for 2018 was 33 ± 38% higher than the 2005–2017 mean. These results indicate that CH4 emissions from areas where the natural source is thought to be relatively small can still vary due to meteorological conditions. At the European scale though, the degree of variability over 2005–2018 was small, and there was negligible impact on the annual CH4 emissions in 2018 despite the extreme meteorological conditions.
This article is part of a discussion meeting issue ‘Rising methane: is warming feeding warming? (part 2)’.
2021
Effects of climate variability on vegetation and carbon uptake in a North-Norwegian coastal wetland. NILU OR
Drivhusgassutveksling mellom terrestre økosystemer og atmosfæren er et viktig element i klimasystemet, og utslipp fra boreale og polare våtmarksområder er muligens avgjørende for den videre utviklingen av atmosfæriske konsentrasjoner av CO2 og metan, fordi de inneholder like mye av disse gassene som atmosfæren i dag. Målet med dette prosjektet var å estimere flukser av CO2 og metan i en nordnorsk kystmyr. Sju år med observasjoner viser at disse er sammenlignbare med verdier fra kystmyr ved lavere breddegrader og klart forskjellige fra alpine og mer kontinentale myr i Nord-Sverige og Nord-Finland. Den også sju år lange serien av meteorologiske data dokumenterer at været i denne perioden var både signifikant varmere (hele året, men spesielt om vinteren) og tørrere (spesielt om sommeren) enn normalen fra perioden 1961-1990. Karbonflukser i vekstperioden er følsomme for både tørke, kulde og forholdene i jordsmonnet før vekstperioden, men netto-økosystem-utvekslingen for et helt år varierer langt mindre.
2015
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