Akustiske studier av fisk og makroplankton over kontinentalsokkelen og det østlige Norskehavet, mars 1992; fordeling, atferd og metodiske problemer.

Hovefagsoppgave i Marin Zoologi, avlagt ved Biologisk institutt, Universitetet i Osl

Changes in water temperature and oxygen: the effect of triploidy on performance and metabolism in large farmed Atlantic salmon

In salmon farming, the use of sterile triploids (3N) can mitigate the problem of escapees interbreeding with wild salmon. However, triploid salmon appear less tolerant to high water temperatures and low oxygen levels compared to diploids (2N). To investigate how the thermal performance and physiology of large (2.5 kg) triploid Atlantic salmon Salmo salar L. differs from those of diploids, both ploidies were subjected to water temperatures between 3 and 18°C. The fish were exposed to reduced oxygen saturations (O2 sat, 70%), termed hypoxia, at 6 and 18°C. Triploids fed more than diploids between 3 and 9°C and at similar levels at 12°C. At 15°C, the feed intake significantly dropped in both ploidies, although more in triploids. During hypoxia, feed intake was higher in triploids at 6°C and equal to diploids at 18°C. The overall feed conversion ratio was similar between ploidies. Muscle energy phosphates were generally lower in triploids than diploids, while muscle glucose, blood haemoglobin and haematocrit were lower in triploids than diploids at ≥12°C. Plasma lactate levels tended to be higher in triploids and increased with increasing temperature and at hypoxia in both ploidies. Plasma cortisol increased in both ploidies at high temperatures and was highest in triploids under hypoxic conditions at 18°C. Triploids had a higher cataract score at the start of the experiment and developed more cataracts throughout the experiment. The present findings show that large triploid Atlantic salmon perform better at colder water temperatures compared to diploids and differ in parts of their physiological expression at increasing and high temperature.publishedVersio

Genomic and functional gene studies suggest a key role of beta-carotene oxygenase 1 like (bco1l) gene in salmon flesh color

publishedVersio

Editorial: Building on the legacy of Water Resources Research

Non

Manglende samsvar mellom teori og praksis i politidistriktenes krisehåndtering

Halvårsstudium i risiko, sårbarhet og beredskap, 2012Politiet har rollen som leder og koordinator av mange kriser, og politiets planer danner derfor grunnlag for mange andre aktørers planverk. Prosjektet viser at politiet har et godt planverk i sin dokumentasjon, kalt ”Politiets Beredskapssystem” (PBS). Til tross for et godt planverk, viser det seg at store deler av politiet velger å operere etter andre prosedyrer og mønstre når kriser oppstår - selv om det er metoder fra planverket som øves. Dette medfører usikkerhet og frustrasjon hos flere samarbeidspartnere. Vi har dokumentert at den vesentligste forskjellen ligger i hvorvidt politiet setter stab eller ikke. Når politiet etablerer stab, opprettes det et formalisert rom for andre samarbeidspartnere. Dette mangler når stab ikke opprettes. Savnet av et formelt samvirkefora er spesielt tydelig når politiet opererer som leder for redningstjenesten gjennom lokal redningssentral (LRS). At politiet finner andre metoder viser seg ikke nødvendigvis å være negativt. Vi har avdekket at politiets faktiske organisasjonsmodell i mange tilfeller kan være vel så effektiv innenfor de gitte ressursrammene. Gjennom prosjektet anbefaler vi politiet å ta en opprydding i sitt planverk, slik at det er i samsvar med faktisk utøvelse av politiets rolle som leder og koordinator av offentlig krisehåndtering

Psychological wellbeing in survivors of cardiac arrest, and its relationship to neurocognitive function

© 2016 Objective To characterise psychological wellbeing in survivors of out-of-hospital cardiac arrest (OHCA), and examine its relationship to cognitive function. Patients Forty-one highly functioning cardiac arrest survivors were drawn from the follow-up cohort of a randomised controlled trial of initial airway management in OHCA (ISRCTN:18528625). Design Psychological wellbeing was assessed with a self-report questionnaire (the Depression Anxiety and Stress Scale; DASS) and cognitive function was examined using the Delayed Matching to Samples (DMS) test from the Cambridge Neuropsychological Test Automated Battery (CANTAB). Results Mean anxiety levels were significantly higher in this patient group than normative data drawn from the general population (p=0.046). Multiple regression analyses showed that cognitive function, measured by the DMS, did not predict any of the DASS scales. Conclusions Anxiety plays an important role in determining perceived QoL in high functioning survivors, but psychological wellbeing is unrelated to cognitive function in this group. To achieve a comprehensive assessment of wellbeing, resuscitation research should consider outcomes beyond neurological function alone

Immersion challenge model for Flavobacterium psychrophilum infection of Atlantic salmon (Salmo salar L.) fry

Flavobacterium psychrophilum is the causative agent of bacterial cold-water disease (CWBD) and rainbow trout fry syndrome (RTFS), which affect salmonids. To better understand this pathogen and its interaction with the host during infection, including to support the development of resistant breeds and new vaccines and treatments, there is a pressing need for reliable and reproducible immersion challenge models that more closely mimic natural routes of infection. The aim of this present study was to evaluate a challenge model developed previously for rainbow trout for use in Atlantic salmon. First, preliminary challenges were conducted in Atlantic salmon (n = 120) and rainbow trout (n = 80) fry using two F. psychrophilum isolates collected from each fish species, respectively; fish had been pretreated with 200 mg/L hydrogen peroxide for 1 h. Thereafter, the main challenge was performed for just one F. psychrophilum isolate for each species (at 2 × 107 CFU/mL) but using larger cohorts (Atlantic salmon: n = 1187; rainbow trout: n = 2701). Survival in the main challenge was 81.2% in Atlantic salmon (21 days post-challenge) and 45.3% in rainbow trout (31 days post-challenge). Mortalities progressed similarly during the preliminary and main challenges for both species, demonstrating the reproducibility of this model. This is the first immersion challenge model of F. psychrophilum to be developed successfully for Atlantic salmon

Environmental temperature sensing using Raman spectra DTS fiber-optic methods

Raman spectra distributed temperature sensing (DTS) by fiber-optic cables has recently shown considerable promise for the measuring and monitoring of surface and near-surface hydrologic processes such as groundwater–surface water interaction, borehole circulation, snow hydrology, soil moisture studies, and land surface energy exchanges. DTS systems uniquely provide the opportunity to monitor water, air, and media temperatures in a variety of systems at much higher spatial and temporal frequencies than any previous measurement method. As these instruments were originally designed for fire and pipeline monitoring, their extension to the typical conditions encountered by hydrologists requires a working knowledge of the theory of operation, limitations, and system accuracies, as well as the practical aspects of designing either short- or long-term experiments in remote or challenging terrain. This work focuses on providing the hydrologic user with sufficient knowledge and specifications to allow sound decisions on the application and deployment of DTS systems.Keywords: Hydrology, Temperature, Fiber opti

Randomised comparison of the effectiveness of the laryngeal mask airway supreme, i-gel and current practice in the initial airway management of out of hospital cardiac arrest: A feasibility study

© 2016 The Author. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. Background: The best initial approach to advanced airway management during out of hospital cardiac arrest (OHCA) is unknown. The traditional role of tracheal intubation has been challenged by the introduction of supraglottic airway devices (SGAs), but there is contradictory evidence from observational studies. We assessed the feasibility of a cluster-randomized trial to compare the i-gel SGA vs the laryngeal mask airway supreme (LMAS) vs current practice during OHCA. Methods: We conducted a cluster-randomized trial in a single ambulance service in England, with individual paramedics as the unit of randomization. Consenting paramedics were randomized to use either the i-gel or the LMAS or usual practice for all patients with non-traumatic adult OHCA, that they attended over a 12-month period. The primary outcome was study feasibility, including paramedic and patient recruitment and protocol adherence. Secondary outcomes included survival to hospital discharge and 90 days. Results: Of the 535 paramedics approached, 184 consented and 171 attended study training. Each paramedic attended between 0 and 11 patients (median 3; interquartile range 2-5). We recruited 615 patients at a constant rate, although the LMAS arm was suspended in the final two months following three adverse incidents. The study protocol was adhered to in 80% of patients. Patient characteristics were similar in the three study arms, and there were no differences in secondary outcomes. Conclusions: We have shown that a prospective trial of alternative airway management strategies in OHCA, cluster randomized by paramedic, is feasible