Artikler, rapporter og annet (arktisk og marin biologi): Nye registreringer
Viser treff 1401-1420 av 1636
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First isolation, identification, phenotypic and genotypic characterization of Brucella abortus biovar 3 from dairy cattle in Tanzania
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-21)Background: Brucellosis is a disease of worldwide public health and economic importance. Successful control is based on knowledge of epidemiology and strains present in an area. In developing countries, most investigations are based on serological assays. This study aimed at investigating a dairy herd experiencing abortions in order to establish within-herd seroprevalence to Brucella spp., identify, ... -
Detection of serum neutralizing antibodies to Simbu sero-group viruses in cattle in Tanzania
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08-15)Background: Orthobunyaviruses belonging to the Simbu sero-group occur worldwide, including the newly recognized Schmallenberg virus (SBV) in Europe. These viruses cause congenital malformations and reproductive losses in ruminants. Information on the presence of these viruses in Africa is scarce and the origin of SBV is unknown. The aim of this study was to investigate the presence of antibodies ... -
Black-legged Kittiwake Rissa tridactyla adults and chicks share the same diet in the southern Barents Sea
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015)The Black-legged Kittiwake Rissa tridactyla population is declining throughout its North Atlantic range. In Norway, the species is classified as Endangered on the Norwegian Red List. Studies of diet are one important requirement for effective management of any species. Because it is easier to sample, chick diet has often been considered a proxy for adult diet in many seabird studies, but the ... -
On the relative effect of spawning asynchrony, sperm quantity, and sperm quality on paternity under sperm competition in an external fertilizer
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-14)How much of a fitness benefit is obtained by dominant males of external fertilizers from releasing ejaculates in synchrony with female egg-release when engaging in sperm competition, and what is the most important sperm trait for paternity in these situations? The Arctic charr (Salvelinus alpinus) is an external fertilizer experiencing intense male-male competition over reproductive opportunities ... -
Morphological divergence between three Arctic charr morphs - the significance of the deep-water environment.
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-14)Morphological divergence was evident among three sympatric morphs of Arctic charr (Salvelinus alpinus (L.)) that are ecologically diverged along the shallow-, deep-water resource axis in a subarctic postglacial lake (Norway). The two deep-water (profundal) spawning morphs, a benthivore (PB-morph) and a piscivore (PP-morph), have evolved under identical abiotic conditions with constant low light ... -
Harbour seal Phoca vitulina movement patterns in the high-Arctic archipelago of Svalbard, Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014-09-03)Harbour seals Phoca vitulina are mainly considered a temperate species, but the world’s northernmost population resides year-round in the high-Arctic archipelago of Svalbard. In this study we document post-moulting at-sea movements of 30 individuals from this population using satellite relay data loggers deployed in the autumns of 2009 and 2010. All of the seals showed a strong preference for ... -
Response of Methanogens in Arctic Sediments to Temperature and Methanogenic Substrate Availability
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06-17)Although cold environments are major contributors to global biogeochemical cycles, comparatively little is known about their microbial community function, structure, and limits of activity. In this study a microcosm based approach was used to investigate the effects of temperature, and methanogenic substrate amendment, (acetate, methanol and H2/CO2) on methanogen activity and methanogen community ... -
Long-distance plant dispersal to North Atlantic islands: colonization routes and founder effect
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-04-15)Long-distance dispersal (LDD) processes influence the founder effect on islands.We use genetic data for 25 Atlantic species and similarities among regional floras to analyse colonization, and test whether the genetic founder effect on five islands is associated with dispersal distance, island size and species traits. Most species colonized postglacially via multiple dispersal events from several ... -
Metabolic and trophic interactions modulate methane production in response to warming
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-04-27)Arctic permafrost soils store large amounts of soil organic carbon (SOC) that could be released into the atmosphere as methane (CH4) in a future warmer climate. How warming affects the complex microbial network decomposing SOC is not understood. We studied CH4 production of Arctic peat soil microbiota in anoxic microcosms over a temperature gradient from 1 to 30 °C, combining metatranscriptomic, ... -
Resistance of a sub-arctic bird community to severe forest damage caused by geometrid moth outbreaks
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-05-01)Outbreaks by geometrid moths periodically cause mass mortality of trees and state changes in understorey vegetation in sub-arctic mountain birch forest in northern Scandinavia. In order to assess the short-term impacts of such disturbance on forest bird communities, we took bird censuses in forest where almost all birch trees had been killed by moth outbreaks 2–4 years before the study and in ... -
Lake size and fish diversity determine resource use and trophic position of a top predator in high-latitude lakes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-03-23)Prey preference of top predators and energy flow across habitat boundaries are of fundamental importance for structure and function of aquatic and terrestrial ecosystems, as they may have strong effects on production, species diversity, and food-web stability. In lakes, littoral and pelagic food-web compartments are typically coupled and controlled by generalist fish top predators. However, the ... -
Complete regression and systemic protective immune responses obtained in B16 melanomas after treatment with LTX-315
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014) -
Neither season nor sex affects the cost of terrestrial locomotion in a circumpolar diving duck: The common eider (Somateria mollissima)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014) -
Bears are simply voles writ large: social structure determines the mechanisms of intrinsic population regulation in mammals
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014) -
At the rainbow's end: high productivity fueled by winter upwelling along an Arctic shelf
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Contrasting optical properties of surface waters across the Fram Strait and its potential biological implications
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014) -
Introduction to the special issue on polar night studies conducted onboard RV Helmer Hanssen in the Svalbard area
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014) -
The relative plasma availabilities of ivermectin in reindeer (Rangifer tarandus tarandus) following subcutaneous and two different oral formulation applications
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014) -
Arctic complexity: A case study on diel vertical migration of zooplankton
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014) -
Improving the accuracy of expression data analysis in time course experiments using resampling
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)