Viser treff 169-188 av 1513

    • Cave-dwelling gastropods (Mollusca: Gastropoda) of Brazil: state of the art and conservation 

      Salvador, Rodrigo Brincalepe; Silva, Fernanda Santos; Cavallari, Daniel caracanhas; Cunha, Carlo Magenta; Bichuette, Maria Elina (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-07-26)
      An up-to-date list of exclusively cave-dwelling gastropod species recorded in Brazil is presented including updated taxonomy, detailed geographic information, and illustration of types. The list includes 18 cave-exclusive (troglobitic) gastropods encompassing 15 land and three freshwater species, with the status of further species pending additional studies. Their unusual morphology and diversity ...
    • Cellulase activity screening using pure carboxymethylcellulose: Application to soluble cellulolytic samples and to plant tissue prints. 

      Johnsen, Hanne Risan; Krause, Kirsten (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      Reliable, rapid and inexpensive detection of cellulolytic enzymes that can be used for a wide variety of biological and environmental samples are currently in high demand. Here, a new cellulase detection protocol is described that circumvents problems observed with popular agar-based methods by exploiting the ability of carboxymethylcellulose (CMC) to form gel-like surfaces on its own. These pure ...
    • Centennial relationships between ocean temperature and Atlantic puffin production reveal shifting decennial trends 

      Hansen, Erpur S.; Sandvik, Hanno; Erikstad, Kjell E.; Yoccoz, Nigel; Anker-Nilssen, Tycho; Bader, Jürgen; Descamps, Sebastien; Hodges, Kevin; Mesquita, Michel d. S.; Reiertsen, Tone Kristin; Varpe, Øystein (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-24)
      The current warming of the oceans has been shown to have detrimental effects for a number of species. An understanding of the underlying mechanisms may be hampered by the non-linearity and non-stationarity of the relationships between temperature and demography, and by the insufficient length of available time series. Most demographic time series are too short to study the effects of climate on ...
    • Cercariae of a Bird Schistosome Follow a Similar Emergence Pattern under Different Subarctic Conditions: First Experimental Study 

      Soldánová, Miroslava; Born-Torrijos, Ana; Kristoffersen, Roar; Knudsen, Rune; Amundsen, Per-Arne; Scholz, Tomas (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-03)
      The emergence of cercariae from infected mollusks is considered one of the most important adaptive strategies for maintaining the trematode life cycle. Short transmission opportunities of cercariae are often compensated by periodic daily rhythms in the cercarial release. However, there are virtually no data on the cercarial emergence of bird schistosomes from freshwater ecosystems in northern ...
    • Cercarial behaviour alters the consumer functional response of three-spined sticklebacks 

      Born-Torrijos, Ana; Paterson, Rachel; van Beest, Gabrielle; Vyhlídalová, Tereza; Henriksen, Eirik Haugstvedt; Knudsen, Rune; Kristoffersen, Roar; Amundsen, Per-Arne; Soldánová, Miroslava (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-01-22)
      <ol> <li>Free-living parasite life stages may contribute substantially to ecosystem biomass and thus represent a significant source of energy flow when consumed by non-host organisms. However, ambient temperature and the predator's own infection status may modulate consumption rates towards parasite prey.</li> <li>We investigated the combined effects of temperature and predator infection status ...
    • Cervid herpesvirus 2 and not Moraxella bovoculi caused keratoconjunctivitis in experimentally inoculated semi-domesticated Eurasian tundra reindeer 

      Tryland, Morten; Sanchez Romano, Javier; Marcin, Nina; Nymo, Ingebjørg Helena; Josefsen, Terje Domaas; Sørensen, Karen Kristine; Mørk, Torill (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-24)
      Background: Infectious keratoconjunctivitis (IKC) is a transmissible disease in semi-domesticated Eurasian reindeer (Rangifer tarandus tarandus). It is regarded as multifactorial and a single causative pathogen has not yet been identified. From clinical outbreaks we have previously identified Cervid herpesvirus 2 (CvHV2) and Moraxella bovoculi as candidates for experimental investigations. Eighteen ...
    • Challenges and opportunities when implementing strategic foresight: lessons learned when engaging stakeholders in climate-ecological research 

      Hamel, Sandra; Ims, Rolf Anker; Yoccoz, Nigel (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-13)
      Ecosystems are currently experiencing rapid changes. Decision-makers need to anticipate future changes or challenges that will emerge in order to implement both short-term actions and long-term strategies for reducing undesirable impacts. Strategic foresight has been proposed to help resolve these challenges for better planning and decision-making in an uncertain future. This structured process ...
    • The challenges of opportunistic sampling when comparing prevalence of plastics in diving seabirds: A multi-species example from Norway 

      Benjaminsen, Stine Charlotte; Dehnhard, Nina; Herzke, Dorte; Johnsen, Arild; Anker-Nilssen, Tycho; Bourgeon, Sophie; Collard, France; Langset, Magdalene; Christensen-Dalsgaard, Signe; Gabrielsen, Geir W. (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-01-18)
      There is a need for baseline information about how much plastics are ingested by wildlife and potential negative consequences thereof. We analysed the frequency of occurrence (FO) of plastics >1 mm in the stomachs of five pursuit-diving seabird species collected opportunistically. Atlantic puffins (Fratercula arctica) found emaciated on beaches in SW Norway had the highest FO of plastics (58.8 %), ...
    • Changed Arctic-alpine food web interactions under rapid climate warming: implication for ptarmigan research 

      Henden, John-André; Ims, Rolf Anker; Fuglei, Eva; Pedersen, Åshild Ønvik (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-05)
      Ptarmigan are herbivorous birds that are year-round residents of alpine and arctic ecosystems — presently subjected to the most rapid climate warming on earth. Yet, compared to other bird taxa there has been little climate impact research on ptarmigan. Ptarmigan population dynamics, in particular in the sub/low-arctic, appears to be strongly influenced by complex interactions with a suite of ...
    • Changes in humpback whale song structure and complexity reveal a rapid evolution on a feeding ground in Northern Norway 

      Tyarks, Saskia C.; Aniceto, Ana Sofia; Ahonen, Heidi; Pedersen, Geir; Lindstrøm, Ulf Ove (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-09)
      Singing behaviour by male humpback whales (Megaptera novaeangliae) has traditionally been associated with low-latitude breeding grounds. However, in recent years, this vocal behaviour has been increasingly reported outside these areas. All singers in a given population sing the same version of a song and this song is continually evolving over time with modifications on different levels within the ...
    • Changes in marine prokaryote composition with season and depth over an Arctic polar year 

      Wilson, Bryan; Müller, Oliver; Nordmann, Eva-Lena; Seuthe, Lena; Bratbak, Gunnar; Øvreås, Lise (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-13)
      As the global climate changes, the higher latitudes are seen to be warming significantly faster. It is likely that the Arctic biome will experience considerable shifts in ice melt season length, leading to changes in photoirradiance and in the freshwater inputs to the marine environment. The exchange of nutrients between Arctic surface and deep waters and their cycling throughout the water column ...
    • Changes in Sea-Ice Protist Diversity With Declining Sea Ice in the Arctic Ocean From the 1980s to 2010s 

      Hop, Haakon; Vihtakari, Mikko; Bluhm, Bodil; Assmy, Philipp; Poulin, Michel; Gradinger, Rolf; Peeken, Ilka; von Quillfeldt, Cecilie; Olsen, Lasse Mork; Zhitina, Ludmila; Melnikov, Igor A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-06)
      The large declines in Arctic sea-ice age and extent over the last decades could have altered the diversity of sea-ice associated unicellular eukaryotes (referred to as sea-ice protists). A time series from the Russian ice-drift stations from the 1980s to the 2010s revealed changes in community composition and diversity of sea-ice protists from the Central Arctic Ocean. However, these observations ...
    • Changes in swimming depths of Atlantic salmon Salmo salar post-smolts relative to light intensity 

      Davidsen, Jan Grimsrud; Plantalech Manel-la, Nuria; Thorstad, E.B; Rikardsen, Audun H.; Økland, F.; Sivertsgård, Rolf; Finstad, B; McKinley, R.S; Diserud, O. H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2008-06-22)
      Eight hatchery-reared Atlantic salmon Salmo salar post-smolts, implanted with acoustic depth sensing transmitters and manually tracked for 5-12 h in the Hardangerfjord (Norway), spent most of their time (49-99%) at 1-3 m depth during the day, whereas four of seven fish tracked were found close (<0.5 m) to the surface at night, with a strong negative cross-correlation between general swimming depth ...
    • Changes in the Proanthocyanidin Composition and Related Gene Expression in Bilberry (Vaccinium myrtillus L.) Tissues 

      Suvanto, Jussi; Karppinen, Katja; Riihinen, Kaisu; Jaakola, Laura; Salminen, Juha-Pekka (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-16)
      Berries of genus <i>Vaccinium</i> are rich in flavonoids and proanthocyanidins (PAs). We studied the PA composition and biosynthesis in bilberry (<i>Vaccinium myrtillus L.</i>) tissues and during fruit development. Soluble PAs, analyzed by UHPLC–MS/MS, were most abundant in stem and rhizome with the mean PA polymerization level varying between 4 and 6 in all tissues. Both A- and B-type PAs were ...
    • Changing Arctic snow cover: A review of recent developments and assessment of future needs for observations, modelling, and impacts 

      Bokhorst, Stef; Pedersen, Stine Højlund; Brucker, Ludovic; Anisimov, Oleg; Bjerke, Jarle W.; Brown, Ross D.; Ehrich, Dorothee (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-03-17)
      Snow is a critically important and rapidly changing feature of the Arctic. However, snow-cover and snowpack conditions change through time pose challenges for measuring and prediction of snow. Plausible scenarios of how Arctic snow cover will respond to changing Arctic climate are important for impact assessments and adaptation strategies. Although much progress has been made in understanding ...
    • Characteristics of early Atlantic cod (Gadus morhua L.) catches based on otoliths recovered from archaeological excavations at medieval to early modern sites in northern Norway 

      Pedersen, Torstein; Amundsen, Colin Patrick; Wickler, Stephen (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-11-17)
      We compared stock origin, size- and age-distributions, and length growth rates derived from Atlantic cod otoliths from archaeological excavations at two sites in northern Norway: Vágar in Lofoten (68◦12 N, ad 1156–1285) and the Værbukta site (70◦57 N, ad 1450–1680). For comparison, modern otoliths were sampled during 1993–2001 from areas situated close to Vágar and Værbukta. Length-at-age from ...
    • Characterization of Microbial Communities in Pilot-Scale Constructed Wetlands with Salicornia for Treatment of Marine Aquaculture Effluents 

      Ma, Xiaona; Song, Xingqiang; Li, Xian; Fu, Songzhe; Li, Meng; Liu, Ying (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04-29)
      Microorganisms play an essential role in the performance of constructed wetlands (CWs) for wastewater treatment. However, there has been limited discussion on the characteristics of microbial communities in CWs for treatment of effluents from marine recirculating aquaculture systems (RAS). This study is aimed at characterizing the microbial communities of pilot-scale CWs with <i>Salicornia bigelovii</i> ...
    • Characterization of Mycobacterium bovis from Humans and Cattle in Namwala District, Zambia 

      Malama, Sydney; Johansen, Tone Kristin Bjordal; Muma, John Bwalya; Munyeme, Musso; Mbulo, Grace; Muwonge, Adrian; Djønne, Berit K; Godfroid, Jacques (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
    • Characterization of the cecum microbiome from wild and captive rock ptarmigans indigenous to Arctic Norway 

      Salgado-Flores, Alejandro; Tveit, Alexander Tøsdal; Wright, A-D; Pope, Phillip; Sundset, Monica Alterskjær (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-11)
      Rock ptarmigans (<i>Lagopus muta</i>) are gallinaceous birds inhabiting arctic and sub-arctic environments. Their diet varies by season, including plants or plant parts of high nutritional value, but also toxic plant secondary metabolites (PSMs). Little is known about the microbes driving organic matter decomposition in the cecum of ptarmigans, especially the last steps leading to methanogenesis. ...
    • Characterization of the gut microbiome of hooded seals (Cystophora cristata) 

      Acquarone, Mario; Salgado, Alejandro Flores; Sundset, Monica Alterskjær (Conference object; Konferansebidrag, 2016-03-14)