528 research outputs found

    Reindeer warble fly larvae found in red deer

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    Seven third instar larvae of the reindeer warble fly (Hypoderma (=Oedemagena) tarandi) were found in a 2-3 year old male red deer {Cervus elaphus) shot on 14 November 1985 at Todalen, western Norway. This it, the first report of H. tarandi from red deer. In reindeer third instar larvae are found from February to June, and the unusual date of this record indicates a delayed development of the larvae due to abnormal host reactions. Warble fly larvae, probably H. tarandi, are also reported from moose {Alces alces) in northern Norway

    Life-history Traits of Charr, Salvelinus alpinus, from a High Arctic Watercourse on Svalbard

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    Three arctic charr (Salvelinus alpinus) morphs coexist within the Dieset watercourse (79°10'N, 11°20'E) on Spitsbergen, Svalbard. Small freshwater resident charr exhibited a very slow growth rate, while large freshwater resident charr grew at a rate comparable to that reported for cannibalistic charr elsewhere. First-time sea migrants of the anadromous charr were similar in size to their more southern-living Norwegian conspecifics, but on average two years older. The average number of sea runs before first-time spawning was 3.6 for males and 4.4 for females. Veteran migrants displayed growth comparable to that of anadromous charr from more southern populations. In all three morphs, sex ratio did not differ from unity. The short-lived small residents matured from an age of 4 years, 3 to 4 years earlier than did large residents and anadromous charr. The majority of small resident and anadromous charr spawn a maximum of three times, while large resident charr may spawn up to seven times. Although 69% of large resident charr were older than 15 years, only 5.7% of reproductive anadromous charr exceeded this age. This divergence may indicate different reproductive strategies between the two morphs. There was no evidence of reproductive isolation between these High Arctic charr morphs. Trois variétés d'omble chevalier (Salvelinus alpinus) coexistent à l'intérieur du cours d'eau Dieset (79° 10' de latit. N., 11° 20' de long. E.) au Spitzberg, dans l'archipel du Svalbard. Le petit omble d'eau douce résident affichait un taux de croissance très lent, tandis que le gros omble d'eau douce résident grossissait à une vitesse comparable à celle rapportée ailleurs pour l'omble cannibale. Les spécimens d'omble anadrome qui migraient pour la première fois vers la mer avaient une taille analogue à celle de leurs congénères norvégiens vivant plus au sud, mais avaient en moyenne deux ans de plus. Le nombre moyen une croissance comparable à celle de l'omble anadrome appartenant à des populations plus méridionales. Chez les trois variétés, la proportion des sexes ne différait pas de la valeur 1. Les petits résidents ne vivaient pas longtemps et devenaient adultes à partir de l'âge de 4 ans, c'est-à-dire 3 ou 4 ans plus tôt que ne le faisaient les plus gros résidents et l'omble anadrome. La plupart des petits résidents et de l'omble anadrome frayaient un maximum de trois fois, tandis que le gros omble résident peut frayer jusqu'à sept fois. Si 69 p. cent des gros ombles résidents avaient plus de 15 ans, seulement 5, 7 p. cent des ombles anadromes reproducteurs dépassaient cet âge - divergence qui pourrait indiquer des stratégies de reproduction différentes pour chaque variété. Rien ne semblait indiquer un isolement reproducteur entre ces variétés d'omble de l'Extrême-Arctique.

    Multiphysics 3D modelling of ironless permanent magnet generators

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    Analytical method is widely used for the preliminary design and optimization of electrical machines. It has short calculation time and low computational cost (cost of simulation codes and supporting hardware), but the calculate result is normally considered to be not as accurate as finite element method (FEM). On the other hand, it is time-consuming to optimize machines with FEM if the optimization is not parallelized. Parallelizing optimization requires many licenses when commercial FEM codes are used, which can be very expensive. Ironless permanent magnet generator has large diameter and small aspect ratio, therefore, multiphysics approach is expected to be used for investigating the magnetic and thermal field. To address the above challenges, this paper presents a multiphysics modelling strategy for the design and optimization of ironless permanent magnet generators. Open-source codes are used to reduce the computational cost. A design example is presented to demonstrate the detail of this design method. This approach is expected to be used in super computer in the future, so that the calculation time can be largely reduced

    Histochemical and enzymatic differences in skeletal muscle from Svalbard reindeer during the summer and winter

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    Enzyme activities and fibre properties in four muscles from Svalbard reindeer, collected during the summer, have been compared with corresponding muscles during the winter. In two muscles, gluteobiceps and semimembranosus, oxidative capacity is higher in winter than in summer; in the other two muscles, semitendinosus and longissimus dorsi, there is no difference with time of the year. The capacity to oxidize fatty acids is low in winter compared with summer, especially in semitendinosus and longissimus. These changes are similar in both sexes. Histochemical studies of the three main fibre types, I (BetaR), HA (°cR) and IIB (aW), from the four muscles show that in male reindeers the muscle fibres are narrower at the end of the winter season than during the summer. The decrease of muscle tissue amounts to about one third of the total volume (33%), of which I accounts for 5%, IIA for 2% and IIB for 26%. The results indicate that the Svalbard reindeer use lean tissue in general, and IIB fibres in particular, in order to survive the hostile arctic winter period at Svalbard.Histokemiska och enzymatiska skillnader i skelettmuskel från Svalbardren mellan sommar och vinter.Abstract in Swedish / Sammandrag: Enzymaktiviteter och fiberegenskaper i fyra av Svalbardrenens muskler, insamlade under sommaren, har jåmforts med motsvarande muskler insamlade under vintern. I två muskler, gluteobiceps och semimembranosus, år oxidativa kapaciteten hogre under vintern an under sommaren; i de andra två musklerna, semitendinosus och longissimus dorsi, foreligger ingen skillnad i detta avseende. Kapaciteten att oxidera fettsyror år låg under vintern jåmfort med sommaren, speciellt i semitendinosus och longissimus. Inga konsskillnader foreligger i dessa avseenden. Histokemiska studier av de tre huvudtyperna av muskelfibrer, fiR (I), ocR (IIA) och (IIB), från de fyra musklerna visar att hos handjuren år fibrerna tunnare vid slutet av vintersåsongen jåmfort med sommaren. Denna minskning i muskelvåvnad uppgår till en tredjedel av totala volymen (33%). Harav svarar ftR for 5%, ^R tor 2% och for 26%. Resultaten antyder att Svalbardrenen anvånder muskelvåvnad, speciellt QcW fibrer, for att overleva undri den hårda arktiska vinterperioden på Svalbard

    Exploring the impact of the somatic method ‘Timani’ on performance quality, performance-related pain and injury, and self-efficacy in music students in Norway: an intervention study

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    The importance of including performance-related body mechanics into music education to improve performance quality and prevent performance-related injuries has been stressed by many researchers recently. However, it is unclear how this information could be delivered most effectively. The somatic method ‘Timani’ provides a practical solution by combining expertise in music performance and functional body mechanics with the goal of achieving a more efficient playing technique. Since no in-depth study has been conducted to assess the method before, we explored the impact of this method on young musicians’ performance through an online, 4-week-long Timani intervention with a mixed-methodology design. 17 students (mean age = 19.17 years) were recruited from the Norwegian Academy of Music. They participated in two group workshops at the beginning and the end of the project and received four individual Timani sessions administered by certified teachers. We collected survey data at the workshops about performance-related pain and self-efficacy, and qualitative feedback after each session. In addition, all sessions were observed by the researcher and semi-structured interviews were conducted with the teachers about the perceived outcomes and their experiences with teaching the method online. Our findings show that the intervention had a positive impact on a physical, professional, and to some extent, psychological and behavioral level. The improvements included better posture when playing, enhanced control and dexterity in the upper extremities, and improved breathing mechanisms. The seven students who had performance-related pain pre-intervention reported a reduction in the discomfort. The positive results were achieved by the dual expertise of the teachers in music performance and functional body mechanics, the structure of the sessions, the communication, and the pedagogical tools used. Both students and teachers felt that administering the sessions online was satisfactory and produced good results. Timani is a promising method to establish healthy playing and singing habits thus improving performance quality and preventing performance-related problems and has great potential in reducing pre-existing injuries and pain. Also, it can be effectively taught online which has further implications for the logistics of delivery

    Sonosensitive dioleoylphosphatidylethanolamine-containing liposomes with prolonged blood circulation time of doxorubicin

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    This article is part of Tove Julie Evjen's doctoral thesis, which is available in Munin at http://hdl.handle.net/10037/3373Ultrasound sensitive (sonosensitive liposomes) are drug delivery systems designed for releasing their drug load upon exposure to ultrasound (US). Inclusion of dioleoylphosphatidylethanolamine (DOPE) in liposome membranes was previously shown to induce sonosensitivity. For efficient US mediated drug delivery to solid tumours, a long blood circulation time of the liposomal drug providing high tumour uptake is required. In this study, blood pharmacokinetics of DOPE-based liposomal doxorubicin (DXR) were evaluated in mice. A markedly faster blood clearance of DXR was observed for DOPE-rich liposomes compared to Caelyx! (standard liposomal DXR). Subsequently, liposome membrane composition was altered to improve drug retention in the bloodstream, while maintaining sonosensitivity. Formulations with reduced blood clearance of DXR were obtained by reducing the content of DOPE from 62 to 32 or 25 mol%. These formulations showed long blood circulation time, as approximately 20% of the administered DXR dose was present in the bloodstream 24 h after intravenous injection. The reduction in liposomal DOPE content did not significantly reduce US mediated DXR release in vitro, indicating that DOPE is a potent modulator to sonosensitivity. The novel liposome formulations, containing moderate amounts of DOPE, displayed similar blood pharmacokinetic profiles as standard liposomal DXR, but a markedly improved sonosensitivity

    Multi-store Competition: Market Segmentation or Interlacing

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    This paper develops a model for multi-store competition between firms. Using the fact that different firms have different outlets and produce horizontally differentiated goods, we obtain a pure strategy equilibrium where firms choose a different location for each outlet and firms' locations are interlaced. The location decisions of multi-store firms are completely independent of each other. Firms choose locations that minimize transportation costs of consumers. Moreover, generically, the subgame perfect equilibrium is unique and when the firms have an equal number of outlets, prices are independent of the number of outlets

    Foraging behaviour of black guillemots at three Norwegian sites during the breeding season

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    The intensifcation of coastal development poses potential threats for coastal seabirds, and understanding their habitat use is a key factor to guide conservation and management. In sub-arctic areas, black guillemots (Cepphus grylle) use coastal habitats year-round, which makes them vulnerable to the increasing human activities in these areas. In mainland Norway, one of the species’ strongholds, black guillemots are red-listed after substantial population declines. However, their fnescale foraging behaviour has received little attention to date. We collected and analysed GPS tracking data from adult black guillemots at three sites located over a latitudinal gradient of 250 km in central/northern Norway. Maximum foraging ranges of 33 km at Sklinna (65°12′N) for incubating birds, and 18 km at both Vega (65°34′N) and Sklinna for chick-rearing birds, are among the longest reported for this species. At all three sites, foraging probability was highest in shallow waters (<50 m depth) close to the colony and declined with increasing water depth and distance from colony. However, birds from Vega also foraged over deeper waters. Kelp presence was of high importance at Sklinna, but apparently less important at Røst (67°26’N) and Vega. We also found distinct diferences in foraging activity across the day and with tidal height among the sites. Inter-site diferences in habitat use and foraging activity may be explained by diferences in the availability of habitats and suitable prey. Our study highlights the importance of shallow marine areas for black guillemots and shows that habitat use can vary substantially between sites. Cepphus grylle · Marine spatial planning · Habitat use · Species distribution model · Kelp forestpublishedVersio
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