Viser treff 1021-1040 av 1513

    • Pelagic occurrences of the ice amphipod Apherusa glacialis throughout the Arctic 

      Kunisch, Erin; Bluhm, Bodil; Daase, Malin; Gradinger, Rolf; Hop, Haakon; Melnikov, Igor A.; Øystein, Varpe; Berge, Jørgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-01-10)
      <i>Apherusa glacialis</i> is a common, sea ice-associated amphipod found throughout the Arctic Ocean and has long been considered permanently associated with the sea ice habitat. However, pelagic occurrences of <i>A. glacialis</i> have also been reported. It was recently suggested that <i>A. glacialis</i> overwinters at depth within the Atlantic-water inflow near Svalbard, to avoid being exported ...
    • Pelagic organisms avoid white, blue, and red artificial light from scientific instruments 

      Geoffroy, Maxime; Langbehn, Tom; Priou, Pierre; Varpe, Øystein; Johnsen, Geir; Le Bris, Arnault; Fisher, Jonathan A. D.; Daase, Malin; Mckee, David; Cohen, Jonathan H.; Berge, Jørgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-22)
      In situ observations of pelagic fish and zooplankton with optical instruments usually rely on external light sources. However, artificial light may attract or repulse marine organisms, which results in biased measurements. It is often assumed that most pelagic organisms do not perceive the red part of the visible spectrum and that red light can be used for underwater optical measurements of biological ...
    • Persistence of arctic-alpine flora during 24,000 years of environmental change in the Polar Urals. 

      Clarke, Charlotte, L.; Edwards, Mary, E.; Gielly, L; Ehrich, Dorothee; Hughes, P.D.M.; Morozova, L.M.; Haflidason, Haflidi; Mangerud, Jan; Svendsen, John-Inge; Alsos, Inger Greve (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-12-23)
      Plants adapted to extreme conditions can be at high risk from climate change; arctic-alpine plants, in particular, could “run out of space” as they are out-competed by expansion of woody vegetation. Mountain regions could potentially provide safe sites for arctic-alpine plants in a warmer climate, but empirical evidence is fragmentary. Here we present a 24,000-year record of species persistence based ...
    • Pestivirus Infections in Semi-Domesticated Eurasian Tundra Reindeer (Rangifer tarandus tarandus): A Retrospective Cross-Sectional Serological Study in Finnmark County, Norway. 

      Neves, Carlos Gonzalo das; Johansson Wensman, Jonas; Nymo, Ingebjørg Helena; Skjerve, Eystein; Alenius, Stefan; Tryland, Morten (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-12-26)
      Members of the Pestivirus genus (family <i>Flaviviridae</i>) cause severe and economically important diseases in livestock. Serological studies have revealed the presence of pestiviruses in different cervid species, including wild and semi-domesticated Eurasian tundra reindeer. In this retrospective study, serum samples collected between 2006 and 2008 from 3339 semi-domesticated Eurasian reindeer ...
    • Pharmacokinetics of a long-acting subcutaneous eprinomectin injection in semi-domesticated reindeer (Rangifer tarandus tarandus) - a pilot study 

      Davidson, Rebecca K.; Fæste, Christiane Kruse; Uhlig, Silvio; Tukun, Feng-Ling; Lian, Hans Edvin; Solvang, Hans Arne; Thorvaldsen, Renate; Folkow, Lars; Sanchez Romano, Javier; Kilvær, Marianne V.; Holmgren, Karin Elisabeth; Nymo, Ingebjørg Helena (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-17)
      Reindeer (Rangifer tarandus tarandus) are exposed to the pathogenic parasitic nematode Elaphostrongylus rangiferi during grazing. The severity of disease is dose-dependent. Prophylactic anthelmintic treatment is needed to improve animal health and reindeer herding sustainability. Herds are traditionally only gathered once during the summer, requiring a drug with a persistent effect. In this study ...
    • Phenological and elevational shifts of plants, animals and fungi under climate change in the European Alps 

      Vitasse, Yann; Ursenbacher, Sylvain; Klein, Geoffrey; Bohnenstengel, Thierry; Chittaro, Yannick; Delestrade, Anne; Monnerat, Christian; Rebetez, Martine; Rixen, Christian; Strebel, Nicolas; Schmidt, Benedikt R.; Wipf, Sonja; Wohlgemuth, Thomas; Yoccoz, Nigel; Lenoir, Jonathan (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-27)
      Mountain areas are biodiversity hotspots and provide a multitude of ecosystem services of irreplaceable socio-economic value. In the European Alps, air temperature has increased at a rate of about 0.36°C decade<sup>−1</sup> since 1970, leading to glacier retreat and significant snowpack reduction. Due to these rapid environmental changes, this mountainous region is undergoing marked changes in spring ...
    • Phenology and cover of plant growth forms predict herbivore habitat selection in a high latitude ecosystem 

      Iversen, Marianne; Fauchald, Per; Langeland, Knut; Ims, Rolf Anker; Yoccoz, Nigel Gilles; Bråthen, Kari Anne (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      The spatial and temporal distribution of forage quality is among the most central factors affecting herbivore habitat selection. Yet, for high latitude areas, forage quantity has been found to be more important than quality. Studies on large ungulate foraging patterns are faced with methodological challenges in both assessing animal movements at the scale of forage distribution, and in assessing ...
    • Phenotype-environment association of the oxygen transport system in trimorphic European whitefish (Coregonus lavaretus) populations 

      Evans, Melissa; Præbel, Kim; Peruzzi, Stefano; Amundsen, Per-Arne; Bernatchez, Louis (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-05-23)
    • Photoperiod and dietary treatment in freshwater modulate the short-term intestinal response to seawater in Atlantic salmon (Salmo salar) 

      Gaetano, Pasqualina; Duarte, Vilma; Striberny, Anja; Hazlerigg, David; Jørgensen, Even Hjalmar; Campinho, Marco A.; Fuentes, Juan (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-02)
      Stimulation and timing of smoltification are essential for successful Atlantic salmon (Salmo salar) aquaculture. This study investigated intestinal responses during dietary and photoperiod manipulation in freshwater (FW) and after a subsequent seven days residence in seawater (SW). “Small” and “large” Atlantic salmon parr (~40 g and ~ 130 g respectively) were treated in FW for 12 weeks and ...
    • Photoperiod revisited: is there a critical day length for triggering a complete parr–smolt transformation in Atlantic salmon Salmo salar? 

      Strand, Jo Espen Tau; Hazlerigg, David; Jørgensen, Even Hjalmar (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-07-26)
      The present study investigated whether there is a critical length of photoperiod needed to stimulate a completed parr–smolt transformation (PST) in Atlantic salmon <i>Salmo salar</i>. In two experiments, <i>S. salar</i> parr of the Norwegian aquaculture strain held on continuous light were exposed to a short photoperiod (6 L:18D) followed by exposure to 8 L:16D, 12 L:12D, 16 L:8D, 20 L:4D and 24 ...
    • Photoperiodic induction without light-mediated circadian entrainment in a High Arctic resident bird 

      Appenroth, Daniel; Melum, Vebjørn Jacobsen; West, Alexander Christopher; Dardente, Hugues; Hazlerigg, David; Wagner, Gabriela (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-21)
      Organisms use changes in photoperiod to anticipate and exploit favourable conditions in a seasonal environment. While species living at temperate latitudes receive day length information as a year-round input, species living in the Arctic may spend as much as two-thirds of the year without experiencing dawn or dusk. This suggests that specialised mechanisms may be required to maintain seasonal ...
    • Photoperiodism and overwintering in boreal and sub-Arctic Calanus finmarchicus populations 

      Coguiec, Estelle; Last, Kim S.; Cohen, Jonathan H.; Hobbs, Laura; Choquet, Marvin; Ershova, Elizaveta; Berge, Jørgen; Daase, Malin (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-08)
      The copepod Calanus finmarchicus, a key species in the North Atlantic, generally spends the non-productive season by descending into deep waters and entering diapause, a physiological state characterized by reduced metabolism and arrested development. In the open ocean, overwintering depths are below 600 m, where temperature and light conditions are favourable to initiate diapause. However, C. ...
    • Photophysiological cycles in Arctic krill are entrained by weak midday twilight during the Polar Night 

      Cohen, Jonathan H.; Last, Kim; Charpentier, Corie L.; Cottier, Finlo; Daase, Malin; Hobbs, Laura; Johnsen, Geir; Berge, Jørgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-19)
      Light plays a fundamental role in the ecology of organisms in nearly all habitats on Earth and is central for processes such as vision and the entrainment of the circadian clock. The poles represent extreme light regimes with an annual light cycle including periods of Midnight Sun and Polar Night. The Arctic Ocean extends to the North Pole, and marine light extremes reach their maximum extent in ...
    • Photophysiological responses of bottom sea-ice algae to fjord dynamics and rapid freshening 

      Forgereau, Zoé Lulu; Lange, Benjamin Allen; Gradinger, Rolf Rudolf; Assmy, Philipp Kurt Wolf; Osanen, Janina; Martín, Laura; Søreide, Janne; Granskog, Mats; Leu, Eva; Campbell, Karley Lynn (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-13)
      Sea ice algae have a broad salinity tolerance but can experience stress during rapid decreases in salinity that occur with seasonal ice melt and during ice sample melt. This study investigated the impact of salinity on the photophysiological responses of bottom-ice algal communities from two Svalbard fjords (Tempelfjorden and Van Mijenfjorden). To further investigate the impact of salinity alone, ...
    • Phthalate contamination in marine mammals off the Norwegian coast 

      Andvik, Clare Margaret; Bories, Pierre; Harju, Mikael; Borgå, Katrine; Jourdain, Eve Marie; Karoliussen, Richard; Rikardsen, Audun Håvard; Routti, Heli Anna Irmeli; Blévin, Pierre (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-27)
      Phthalates are used in plastics, found throughout the marine environment and have the potential to cause adverse health effects. In the present study, we quantified blubber concentrations of 11 phthalates in 16 samples from stranded and/or free-living marine mammals from the Norwegian coast: the killer whale (Orcinus orca), sperm whale (Physeter macrocephalus), long-finned pilot whale (Globicephala ...
    • Phthalate metabolites in harbor porpoises (Phocoena phocoena) from Norwegian coastal waters 

      Rian, May Britt; Vike-Jonas, Kristine; Gonzalez, Susana Villa; Ciesielski, Tomasz Maciej; Venkatraman, Vishwesh; Lindstrøm, Ulf; Jenssen, Bjørn Munro; Asimakopoulos, Alexandros (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-03)
      The exposure of marine mammals to phthalates has received considerable attention due to the ubiquitous occurrence of these pollutants in the marine environment and their potential adverse health effects. The occurrence of phthalate metabolites is well established in human populations, but data is scarce for marine mammals. In this study, concentrations of 17 phthalate metabolites were determined in ...
    • Phylogenetic and genomic analysis of Methanomassiliicoccales in wetlands and animal intestinal tracts reveals clade-specific habitat preferences 

      Söllinger, Andrea; Schwab, Clarissa; Weinmaier, Thomas; Loy, Alexander; Tveit, Alexander Tøsdal; Schleper, Christa; Urich, Tim (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-27)
      Methanogenic Thermoplasmata of the novel order Methanomassiliicoccales were recently discovered in human and animal gastro-intestinal tracts (GITs). However, their distribution in other methanogenic environments has not been addressed systematically. Here, we surveyed Methanomassiliicoccales presence in wetland soils, a globally important source of methane emissions to the atmosphere, and in the ...
    • Phylogenetic position of African punctoid snails (Stylommatophora, Punctoidea, Trachycystinae) 

      Salvador, Rodrigo Brincalepe (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-02)
      The punctoid land snail family Charopidae, as currently defined, is a paraphyletic assemblage of taxa with Gondwanan distribution. It is represented in Africa largely by the pinwheels (genus Trachycystis and allies) and afrodontas (genus Afrodonta and allies), as well as a few additional genera, such as Reticulapex, Pilula, and Helenoconcha. Herein, a Bayesian inference phylogenetic analysis (using ...
    • Phylogenetic position of the relict South American genus Idiopyrgus Pilsbry, 1911 (Gastropoda, Truncatelloidea), with the description of two new cave species 

      Salvador, Rodrigo Brincalepe; Silva, Fernanda Santos; Bichuette, Maria Elina (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-14)
      Idiopyrgus is a relict genus of freshwater snails from Brazil traditionally classified in the family Pomatiopsidae. Herein, we use molecular data from newly acquired specimens to test that classification through Bayesian inference phylogenetic analysis. We conclude that Idiopyrgus belongs in the Gondwanan family Tomichiidae, together with the African genus Tomichia and the Australian genus Coxiella. ...
    • Phylogenetic Reclassification of Vertebrate Melatonin Receptors To Include Mel1d 

      Denker, Elsa; Ebbesson, Lars O.E.; Hazlerigg, David; Macqueen, Daniel J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-01)
      The circadian and seasonal actions of melatonin are mediated by high affinity G-protein coupled receptors (melatonin receptors, MTRs), classified into phylogenetically distinct subtypes based on sequence divergence and pharmacological characteristics. Three vertebrate MTR subtypes are currently described: MT1 (MTNR1A), MT2 (MTNR1B), and Mel1c (MTNR1C / GPR50), which exhibit distinct affinities, ...