Blood and feather concentrations of toxic elements in a Baltic and an Arctic seabird population

We report blood and feather concentrations of elements in the Baltic Sea and Arctic population of common eiders (Somateria mollissima). The endangered Baltic Sea population of eiders was demonstrably affected by element pollution in the 1990s. While blood concentrations of Hg were higher in Baltic breeding eiders, blood Se, As and Cd concentrations were higher in Arctic eiders. Blood concentrations of Pb, Cr, Zn and Cu did not differ between the two populations. While blood Pb concentrations had declined in Baltic eiders since the 1990s, Hg concentrations had not declined, and were above concentrations associated with adverse oxidative effects in other bird species. Inconsistent with blood concentrations, feather concentrations suggested that Pb, Zn, and Cd exposure was higher in Baltic eiders, and that Hg exposure was higher in Arctic eiders. Our study thus emphasizes the need for comprehensive evaluation of toxic element status, covering the annual cycle of a species. (C) 2016 Elsevier Ltd. All rights reserved.Peer reviewe

From polar night to midnight sun: Diel vertical migration, metabolism and biogeochemical role of zooplankton in a high Arctic fjord (Kongsfjorden, Svalbard)

Source at http://dx.doi.org/10.1002/lno.10519 Zooplankton vertical migration enhances the efficiency of the ocean biological pump by translocating carbon (C) and nitrogen (N) below the mixed layer through respiration and excretion at depth. We measured C and N active transport due to diel vertical migration (DVM) in a Svalbard fjord at 79°N. Multifrequency analysis of backscatter data from an Acoustic Zooplankton Fish Profiler moored from January to September 2014, combined with plankton net data, showed that Thysanoessa spp. euphausiids made up > 90% of the diel migrant biomass. Classical synchronous DVM occurred before and after the phytoplankton bloom, leading to a mismatch with intensive primary production during the midnight sun. Zooplankton DVM resulted in C respiration of 0.9 g m−2 and ammonium excretion of 0.18 g N m−2 below 82 m depth between February and April, and 0.2 g C m−2 and 0.04 g N m−2 from 11 August to 9 September, representing > 25% and > 33% of sinking flux of particulate organic carbon and nitrogen, respectively. Such contribution of DVM active transport to the biological pump in this high-Arctic location is consistent with previous measurements in several equatorial to subarctic oceanic systems of the World Ocean. Climate warming is expected to result in tighter coupling between DVM and bloom periods, stronger stratification of the Barents Sea, and northward advection of boreal euphausiids. This may increase the role of DVM in the functioning of the biological pump on the Atlantic side of the Arctic Ocean, particularly where euphausiids are or will be prevalent in the zooplankton community

Impacts of a warming climate on concentrations of organochlorines in a fasting high arctic marine bird: Direct vs. indirect effects?

The present study examined how climate changes may impact the concentrations of lipophilic organochlorines (OCs) in the blood of fasting High Arctic common eiders (Somateria mollissima) during incubation. Polychlorinated biphenyls (PCBs), 1-dichloro-2,2-bis (p-chlorophenyl) ethylene (p,p′-DDE), hexachlorobenzene (HCB) and four chlordane compounds (oxychlordane, trans-chlordane and trans- and cis-nonachlor) were measured in females at chick hatching (n = 223) over 11 years (2007–2017). Firstly, median HCB and p,p′-DDE concentrations increased ~75 % over the study period, whereas median chlordane concentrations doubled (except for oxychlordane). PCB concentrations, in contrast, remained stable over the study period. Secondly, both body mass and clutch size were negatively associated with OC levels, suggesting that females with high lipid metabolism redistributed more OCs from adipose tissue, and that egg production is an important elimination route for OCs. Thirdly, the direct climate effects were assessed using the mean effective temperature (ET: air temperature and wind speed) during incubation, and we hypothesized that a low ET would increase redistribution of OCs. Contrary to expectation, the ET was positively correlated to most OCs, suggesting that a warmer climate may lead to higher OCs levels, and that the impact of ET may not be direct. Finally, potential indirect impacts were examined using the Arctic Oscillation (AO) in the three preceding winters (AOwinter 1–3) as a proxy for potential long-range transport of OCs, and for local spring climate conditions. In addition, we used chlorophyll a (Chla) as a measure of spring primary production. There were negative associations between AOwinter 1 and HCB, trans-chlordane and trans-nonachlor, whereas oxychlordane and cis-chlordane were negatively associated with Chla. This suggests that potential indirect climate effects on eiders were manifested through the food chain and not through increased long-range transport, although these relationships were relatively weak.Impacts of a warming climate on concentrations of organochlorines in a fasting high arctic marine bird: Direct vs. indirect effects?publishedVersio

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Is paternal age associated with transfer day, developmental stage, morphology, and initial hCG-rise of the competent blastocyst leading to live birth?:A multicenter cohort study

In this study we investigated whether age of men undergoing assisted reproductive technology (ART) treatment was associated with day of transfer, stage, morphology, and initial hCG-rise of the competent blastocyst leading to a live birth? The design was a multicenter historical cohort study based on exposure (age) and outcome data (blastocyst stage and morphology and initial hCG-rise) from men whose partner underwent single blastocyst transfer resulting in singleton pregnancy/birth. The ART treatments were carried out at sixteen private and university-based public fertility clinics. We included 7246 men and women, who between 2014 and 2018 underwent controlled ovarian stimulation (COS) or Frozen-thawed Embryo Transfer (FET) with a single blastocyst transfer resulting in singleton pregnancy were identified. 4842 men with a partner giving birth were included, by linking data to the Danish Medical Birth Registry. We showed that the adjusted association between paternal age and transfer day in COS treatments was OR 1.06, 95% CI (1.00;1.13). Meaning that for every increase of one year, men had a 6% increased probability that the competent blastocyst was transferred on day 6 compared to day 5. Further we showed that the mean difference in hCG values when comparing paternal age group 30–34, 35–39 and 40–45 with the age group 25–29 in those receiving COS treatment, all showed significantly lower adjusted values for older men. In conclusion we hypothesize that the later transfer (day 6) in female partners of older men may be due to longer time spent by the oocyte to repair fragmented DNA of the sperm cells, which should be a focus of future research in men

Naturfaglige skriveoppgaver for 4.trinn. En undersøkelse av skriveoppgaver i Gaia 4 og Cumulus 4.

Denne masteroppgaven handler om skriveoppgaver i naturfagsbøker for 4.trinn. En analyse av skriving i prosess og type skrivehandling i et utvalg skriveoppgaver fra Gaia 4 og Cumulus 4, forteller i hvilken grad lærebokoppgavene kan bidra til utvikling av skriving som grunnleggende ferdighet i naturfag. Det teoretiske fundamentet i oppgaven er først og fremst teori bak POS (Dysthe, 1999, og Dysthe og Hertzberg, 2014) og teorien bak Skrivehjulet (Berge, Evensen og Thygesen, 2016). Hensikten med prosjektet er å bidra til bevissthet blant lærere, skoleledere og forlag rundt lærebokoppgavenes betydning for elevenes læring slik Skjelbred (2009, s. 274) forklarer oppgaver som paratekster (Skjelbred, 2009). Oppgavene er også viktige fordi mye av skriveopplæringen i skolen er knyttet til oppgaveløsing (Skjelbred et al., 2005, Klette 2004, referert i Skjelbred, 2009). Den metodiske tilnærmingen i dette prosjektet er en kvalitativ lærebokanalyse. 34 oppgaver fra Gaia 4 og Cumulus 4 er kategorisert etter skriving i prosess og type skrivehandling. Gaia 4 Natur- og samfunnsfag elevbok er utgitt av Gyldendal norsk forlag i 2007 (Holm et al., 2007). Utvalget består av oppgaver som lærerveiledninga definerer innenfor skriving som grunnleggende ferdighet fra tre kapitler. Cumulus 4 Natur- og samfunnsfag er utgitt av Aschehoug forlag i 2008 (Bjørshol et al., 2008). Lærebokas nøtteoppgaver er valgt ut til analysen. Hovedkonklusjonen er at skriveoppgavene i utvalget i noe grad legger opp til skriving som grunnleggende ferdighet i naturfag. Ett av funnene viser at mange skriveoppgaver indikerer skriving i prosess, men ingen av dem krever planlegging eller bearbeiding av tekst. Dette er en del av skriveprosessen i naturfag ifølge LK06. Derfor vil det være opp til den enkelte lærer hvorvidt elevene får undervisning i bruk og valg av hensiktsmessige skrivestrategier til arbeid i ulike faser av skriveprosessen. Et annet funn viser at de fleste oppgavene legger opp til utforskning og beskrivelser. Ordlyden i de utforskende oppgavene tilsier at en må vurdere om de faktisk legger opp til utforskning, eller om det er beskrivelser ikledd som utforskende oppgaver. Skriveoppgavene i utvalget krever derfor stort sett at elevene skal reprodusere kunnskap skriftlig gjennom beskrivelser. En mulig konsekvens kan være at skriveopplæringen ikke blir tilstrekkelig for at elevene utvikler nødvendig skrivekompetanse som faget krever. Spørsmålet som gjenstår er hvilke elever dette vil gå mest utover