Search results for "Matematik"

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

Theoretical Studies in Solar Cell Physics

2022

Paper VI is excluded from the dissertation until it will be published. In this thesis, we develop analytical models with the purpose of expanding knowledge and gaining understanding of some of the internal mechanisms that limit the efficiency of single-junction solar cells. We focus on three distinct topics: fundamental energy losses, the temperature sensitivity of single-junction solar cells and the effect of the series resistance on the maximum power point. The thesis is divided in two parts. The first part reviews basic solar cell physics topics and introduces some more advanced concepts to provide the reader with the necessary background to understand the attached papers. The latter con…

Recolonization and recovery of an Arctic benthic community subject to mine-tailings deposits

2023

Information Quality in Secondary Use of EHR Data : A Case Study of Quality Management in a Norwegian Hospital

2019

The motivation for undertaking this study relates to my experiences from practice in a public hospital, where I have observed variations in reaching organizational goals of quality management informed by electronic health records (EHR) data. For example, while some departments and units have long-time traditions in meeting the quality goals that are set locally, regionally, or nationally, other departments and units struggle to meet the same quality goals. Thus, generating actionable information by reusing routinely collected EHR data does not necessary lead to action in response to the information. This process of generating information from existing EHR data, and communicating and using s…

SMS-based Real-time Data Collection for Evaluation of Situational Awareness and Common Operational Picture : Lessons Learned from A Field Exercise

2020

Managing complex multi-agency emergency operations requires that the key actors have a holistic, correct and dynamic situational awareness (SA) and that the involved actors establish a common operational picture (COP). Establishing SA and COP are key objectives in many multi-agency exercises, however, reported research shows limitations in existing methods and approaches for collecting the data required for evaluating this. By being able to capture near real-time information during different phases of the exercise we will be better positioned to identify what works well and what does not work in the process of establishing SA and COP. Our paper presents an example of real-time data collecti…