Search results for "47"

Time at risk: individual spatial behaviour drives fitness and marine protected area effectiveness

2021

The effectiveness of Marine Protected Areas (MPAs) depends on the mobility of the populations that are the target of protection, with sedentary species likely to spend more time under protection even within small MPAs. However, little is understood about how individual variation in mobility may influence the risk of crossing an MPA border, as well as the fitness costs associated with being exposed to spillover fisheries. Here we investigated the repeatability of spatial behaviour, its role in determining the probability of being at risk (i.e. exposed to the fishery) and the fitness consequences for the individuals. We acoustically tracked the movements and fate of 282 individuals of three f…

Spatial patterns of pathogen prevalence in questing Ixodes ricinus nymphs in southern Scandinavia

2020

Salmon lice (Lepeophtheirus salmonis) in the stomach contents of lumpfish (Cyclopterus lumpus) sampled from Norwegian fish farms: Relationship betwee…

2023

Cleaner fish are commonly used as a control measure against salmon lice infestations in salmonid farms. Lumpfish (Cyclopterus lumpus) is the most common cleaner fish species used in Norwegian farms. However, little is known about how different operational, including environmental, conditions affect the salmon lice grazing efficacy by lumpfish. In this paper, we analyse salmon lice (Lepeophtheirus salmonis) in the stomach contents of a large sample of more than 20,000 lumpfish from 80 different Norwegian farms. We investigate the proportion of lumpfish with salmon lice and the mean number of salmon lice in the stomach contents of the lumpfish. We further explore how the salmon lice contents …

Attraction of cod Gadus morhua from coastal spawning grounds to salmon farms

2022

Wild fish aggregate at aquaculture net-pens, but the underlying mechanisms are not fully understood. This study examined how salmon farms attract coastal Atlantic cod Gadus morhua from their inshore spawning grounds. Acoustic receivers were deployed at 5 known cod spawning grounds and 6 salmon Salmo salar farms located at varying distances from these grounds in a mid-Norway study site. Cod were caught at each spawning ground annually from 2017-2019, fitted with acoustic transmitters and released (n = 535). A total of 289 tagged cod (54%) were detected at the salmon farms, with more cod detected at farms closest to the focal spawning grounds and at operational farms. The latter result is lik…

Genomic analysis of anadromous brown trout (Salmo trutta) reveals new insights into connectivity patterns and population divergence

2018

Master's thesis Aquatic Ecology BIO500 - University of Agder 2018 A large body of studies on brown trout genetics currently exists. However, fewer of these studies have been conducted on anadromous brown trout (sea trout) and have been limited to only a few genetic markers like allozymes, mtDNA or microsatellites. Here we analyzed population structure and connectivity in sea trout applying a modern genomic approach, analyzing 503 single nucleotide polymorphic variants (SNP’s) by next generation sequencing. We studied four streams along the Skagerrak coast and found an overall significant population structure (FST = 0.0161; P<0.01) which further seemed to constitute of three genetically dist…

Kopepoder langs Skagerrakkysten - En oversikt basert på morfologisk og molekylærgenetisk identifisering

2018

Masteroppgave akvatisk økologi BIO500 - Universitetet i Agder 2018 Konfidensiell til / confidential until 01.07.2023

Thermally Induced Isomerization of Trilinolein and Trilinoelaidin at 250 A degrees C: Analysis of Products by Gas Chromatography and Infrared Spectro…

2009

Accepted version of an article published in the journal: Lipids The original publication is available at www.springerlink.com, http://dx.doi.org/10.1007/s11745-009-3363-x The products formed by thermally induced isomerization of trilinolein and trilinoelaidin at 250 A degrees C were studied by infrared spectroscopy and gas chromatography. The triglycerides of the 9c12c and 9t12t fatty acids, linoleic and linoelaidic acid respectively, were subjected to thermal treatment under nitrogen in glass. The products were removed at regular intervals and analysed by infrared spectroscopy using a single reflectance attenuated total internal reflectance crystal accessory. Trans-esterification of the pr…

Thermal Induction of 9t12t Linoleic Acid: a New Pathway for the Formation of Conjugated Linoleic Acids

2009

Accepted version of an article published in the journal: International Journal of Engineering and Technology Published version available at: http://www.ijetch.org/papers/066.pdf Thermal induction of 9t12t fatty acid leading to the formation of Conjugated Linoleic Acids (CLA) has been demonstrated by subjecting glyceride, and methyl ester of the acid to heat treatment. Fifteen micro liter portions of the glyceride sample containing 9t12t fatty acid (trilinoelaidin) were placed in micro glass ampoules and sealed under nitrogen and then subjected to thermal treatment at 250oC. The glass ampoules were taken out at regular time intervals, and the contents were subjected to composition analysis b…

VEGF-B-induced vascular growth leads to metabolic reprogramming and ischemia resistance in the heart

2014

Abstract Angiogenic growth factors have recently been linked to tissue metabolism. We have used genetic gain‐ and loss‐of function models to elucidate the effects and mechanisms of action of vascular endothelial growth factor‐B (VEGF‐B) in the heart. A cardiomyocyte‐specific VEGF‐B transgene induced an expanded coronary arterial tree and reprogramming of cardiomyocyte metabolism. This was associated with protection against myocardial infarction and preservation of mitochondrial complex I function upon ischemia‐reperfusion. VEGF‐B increased VEGF signals via VEGF receptor‐2 to activate Erk1/2, which resulted in vascular growth. Akt and mTORC1 pathways were upregulated and AMPK downregulated, …

Road Functional Classification Using Pattern Recognition Techniques

2019

The existing international standards suggest a methodology to assign a specific functional class to a road, by the values of some features, both geometrical and use-related. Sometimes, these characteristics are in contrast with each other and direct the analyst towards conflicting classes for a road or, worse, one or more of these features vary heterogeneously along the road. In these conditions, the analyst assigns the class that, by his capability and experience, he retains the most appropriate, in a very subjective way. On the contrary, the definition of an automatic procedure assuring an objective identification of the most appropriate functional class for each road would be desirable. …