Opin vísindi
Opin vísindi er varðveislusafn vísindaefnis og doktorsritgerða í opnum aðgangi á vegum íslenskra háskóla og Landsbókasafns Íslands - Háskólabókasafns.
Opinn aðgangur að rannsóknaniðurstöðum er í samræmi við 10. gr. laga nr. 3/2003 um opinberan stuðning við vísindarannsóknir sem og kröfur innlendra og erlendra rannsóknasjóða. Markmiðið með opnum aðgangi er að niðurstöður rannsókna séu aðgengilegar sem flestum óhindrað og án endurgjalds á rafrænu formi. Vistun í varðveislusafninu er varanleg og ætlað að tryggja aðgang að vísindaefni íslenskra háskóla í opnum aðgangi um ókomna tíð. Varðveislusafnið Opin vísindi er tengt við rannsóknagáttina IRIS og rannsóknaniðurstöður í opnum aðgangi sem eru skráðar í IRIS eru um leið vistaðar og gerðar aðgengilegar til framtíðar í varðveislusafninu. Með því að safna þessu efni saman í eitt safn verður aðgangur að því einfaldur og þægilegur fyrir alla sem vilja kynna sér það og geta þannig notið þess öfluga vísindastarfs sem fram fer í háskólum landsins.
Varðveislusafnið er OpenAIRE / OpenAIREplus samhæft og samrýmist kröfum sem gerðar eru um birtingu rannsóknaniðurstaðna úr verkefnum sem styrkt eru úr evrópsku rannsóknaáætlununum FP7 og H2020.
Varðveislusafnið notar opna hugbúnaðinn DSpace.
Opinn aðgangur að rannsóknaniðurstöðum er í samræmi við 10. gr. laga nr. 3/2003 um opinberan stuðning við vísindarannsóknir sem og kröfur innlendra og erlendra rannsóknasjóða. Markmiðið með opnum aðgangi er að niðurstöður rannsókna séu aðgengilegar sem flestum óhindrað og án endurgjalds á rafrænu formi. Vistun í varðveislusafninu er varanleg og ætlað að tryggja aðgang að vísindaefni íslenskra háskóla í opnum aðgangi um ókomna tíð. Varðveislusafnið Opin vísindi er tengt við rannsóknagáttina IRIS og rannsóknaniðurstöður í opnum aðgangi sem eru skráðar í IRIS eru um leið vistaðar og gerðar aðgengilegar til framtíðar í varðveislusafninu. Með því að safna þessu efni saman í eitt safn verður aðgangur að því einfaldur og þægilegur fyrir alla sem vilja kynna sér það og geta þannig notið þess öfluga vísindastarfs sem fram fer í háskólum landsins.
Varðveislusafnið er OpenAIRE / OpenAIREplus samhæft og samrýmist kröfum sem gerðar eru um birtingu rannsóknaniðurstaðna úr verkefnum sem styrkt eru úr evrópsku rannsóknaáætlununum FP7 og H2020.
Varðveislusafnið notar opna hugbúnaðinn DSpace.
Flokkar í Opnum vísindum
Veldu flokk til að skoða.
- University of Iceland
- University of Akureyri
- Bifröst University
- Hólar University College
- Reykjavík University
- IRIS
- Agricultural University of Iceland
- National and University Library of Iceland
- Iceland University of the Arts
Nýlega bætt við
The genetic structure of Norway
(2021-11) Mattingsdal, Morten; Ebenesersdóttir, Sigríður Sunna; Moore, Kristjan Helgi Swerford; Andreassen, Ole A.; Hansen, Thomas Folkmann; Werge, Thomas M.; Kockum, Ingrid; Olsson, Tomas; Alfredsson, Lars; Helgason, Agnar Sturla; Stefánsson, Kári; Hovig, Eivind; Faculty of Sociology, Anthropology and Folkloristics
The aim of the present study was to describe the genetic structure of the Norwegian population using genotypes from 6369 unrelated individuals with detailed information about places of residence. Using standard single marker- and haplotype-based approaches, we report evidence of two regions with distinctive patterns of genetic variation, one in the far northeast, and another in the south of Norway, as indicated by fixation indices, haplotype sharing, homozygosity, and effective population size. We detect and quantify a component of Uralic Sami ancestry that is enriched in the North. On a finer scale, we find that rates of migration have been affected by topography like mountain ridges. In the broader Scandinavian context, we detect elevated relatedness between the mid- and northern border areas towards Sweden. The main finding of this study is that despite Norway’s long maritime history and as a former Danish territory, the region closest to mainland Europe in the south appears to have been an isolated region in Norway, highlighting the open sea as a barrier to gene flow into Norway.
MS og barnsburður : Sjúkdómsvirkni og útkoma meðgöngu og fæðingar
(2020) Bergþórsdóttir, Bryndís Björk; Pórhallsdóttir, Rebekka Lísa; Steingrímsdóttir, Þóra; Hjaltason, Haukur; Læknadeild
INNGANGUR MS (multiple sclerosis) er langvinnur bólgusjúkdómur í miðtaugakerfi sem einkennist af köstum, einkum hjá ungu fólki, konum frekar en körlum. Meðgöngu- og fæðingarsaga íslenskra kvenna með MS hefur ekki verið rannsökuð áður. Markmið rannsóknarinnar var tvíþætt, annars vegar að skoða sjúkdómsmynd MS á meðgöngu og fyrstu mánuðum eftir fæðingu og hins vegar að kanna útkomu meðgöngu og fæðingar kvenna með MS og bera saman við hóp kvenna sem ekki hafa greinst með MS eða annan langvinnan sjúkdóm. EFNIVIÐUR OG AÐFERÐIR Afturskyggn rannsókn á gögnum úr sjúkraskrá Landspítala og Fæðingaskráningu Embættis landlæknis sem náði til kvenna með greininguna MS (ICD-10: G35) á árunum 2009-2018 og fæðinga þeirra á tímabilinu 1999-2018, alls 91 konu og 137 fæðinga. NIÐURSTÖÐUR Köstum fækkaði á fyrsta og öðrum þriðjungi meðgöngu miðað við árið fyrir þungun. Rúmlega helmingur kvennanna var á fyrirbyggjandi lyfjameðferð fyrir meðgöngu og hættu þær allar meðferðinni um eða fyrir getnað. Konur með MS fæddu oftar með keisaraskurði án fæðingarsóttar. Meðgöngulengd kvenna með MS var sambærileg við samanburðarhóp þegar sótt hófst sjálfkrafa. Ekki var munur á fjölda léttbura eða þungbura milli hópa. Apgar-stigun var sambærileg milli hópa. ÁLYKTUN Við teljum að rannsókn okkar endurspegli vel meðgöngu- og fæðingarsögu kvenna með MS á Íslandi og að niðurstöður sýni að þær skeri sig lítt úr almennu þýði. Niðurstöður okkar samrýmast erlendum rannsóknum um lægri kastatíðni á meðgöngu en munurinn er þó sá að í okkar rannsókn eru þau áhrif bundin við fyrsta og annan þriðjung meðgöngu. Introduction: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system which affects young people, especially women. The aim of the study was to examine the disease profile of MS during pregnancy and postpartum as well as pregnancy outcomes in women with MS compared to a control group. Such a study has not been conducted in Iceland before. Material and methods: A hospital based retrospective study with data from the Icelandic Medical Birth Register and medical records from Landspitali University Hospital including women with MS diagnosis during 2009-2018 and their deliveries through 1999-2018, a total of 91 women and 137 births. Results: Relapse frequency decreased during pregnancy compared to the preceding year. Over half of the women received disease modifying drugs before pregnancy, all stopped treatment before or shortly after conception. Women in the study group underwent cesarean sections before labor more frequently than the control group. The gestational length was comparable between the groups when labor was spontaneous. The numbers of heavy- and lightweight newborns as well as Apgar scores were alike in both groups. Conclusion: We believe that our study reflects actual pregnancy outcome among Icelandic women with MS and our results show that their pregnancies and deliveries do not differ in any major aspect from the general population. Our findings agree with previous studies in that pregnancy protects against MS relapses although in our study this is confined to the first and second trimester.
Upper Miocene and Pliocene geomagnetic secular variation in the Borgarfjördur area of Western Iceland
(1977-06-01) Watkins, N. D.; McDougall, Ian; Kristjánsson, Leó; Science Institute
A total of 362 successive lava flows, which were extruded at a regular rate between t= 6.7 and 1.6 Myr in the Borgarfjördur area of Western Iceland, have been subjected to palaeomagnetic study. In contrast to the result of a study by Wilson & McElhinny of palaeo‐magnetic data from a long sequence of lava flows in Eastern Iceland, there does not exist any long‐term increase of geomagnetic inclination in Western Iceland between t= 7 and 3 Myr which, as they show, would produce a change in the distance to the associated virtual geomagnetic poles (VGP's) from greater than the geographic co‐latitude to less than the co‐latitude (or, with respect to the site, from ‘far side’ of the geographic pole to ‘near‐side’ of the geographic pole). Instead the geomagnetic inclination is less than that required for an axial dipole field, providing ‘far‐side’ VGP positions for all data groups. The mean VGP positions are almost identical for four successive polarity epochs (two of reversed polarity, and two of normal polarity), consistent with reversal of the main dipole being accompanied by reversal of the non‐dipole field. S F the angular standard deviation of groups of VGP positions, is used as an expression of palaeosecular variation of the magnetic field. It is shown to be almost constant throughout the 5‐Myr period, suggesting that standing and drifting non‐dipole fields have not combined to produce strong secular variation which is in principle possible in high latitudes. This conclusion is weakened by the suspicion that the conventional exclusion of data from lavas with low‐latitude VGP positions has discriminated against the discovery of high palaeosecular variation rates.
Aerial photogrammetry and tag-derived tissue density reveal patterns of lipid-store body condition of humpback whales on their feeding grounds
(2021-01-27) Aoki, Kagari; Isojunno, Saana; Bellot, Charlotte; Iwata, Takashi; Kershaw, Joanna; Akiyama, Yu; Martín López, Lucía M.; Ramp, Christian; Biuw, Martin; Swift, René; Wensveen, Paulus Jacobus; Pomeroy, Patrick; Narazaki, Tomoko; Hall, Ailsa; Sato, Katsufumi; Miller, Patrick J.O.
Monitoring the body condition of free-ranging marine mammals at different life-history stages is essential to understand their ecology as they must accumulate sufficient energy reserves for survival and reproduction. However, assessing body condition in free-ranging marine mammals is challenging. We cross-validated two independent approaches to estimate the body condition of humpback whales (Megaptera novaeangliae) at two feeding grounds in Canada and Norway: animal-borne tags (n = 59) and aerial photogrammetry (n = 55). Whales that had a large length-standardized projected area in overhead images (i.e. whales looked fatter) had lower estimated tissue body density (TBD) (greater lipid stores) from tag data. Linking both measurements in a Bayesian hierarchical model to estimate the true underlying (hidden) tissue body density (uTBD), we found uTBD was lower (-3.5 kg m -3) in pregnant females compared to adult males and resting females, while in lactating females it was higher (+6.0 kg m -3). Whales were more negatively buoyant (+5.0 kg m -3) in Norway than Canada during the early feeding season, possibly owing to a longer migration from breeding areas. While uTBD decreased over the feeding season across life-history traits, whale tissues remained negatively buoyant (1035.3 ± 3.8 kg m -3) in the late feeding season. This study adds confidence to the effectiveness of these independent methods to estimate the body condition of free-ranging whales.
A comparison of two different slaughter systems for lambs. Effects on carcass characteristics, technological meat quality and sensory attributes
(2021-10-11) Stenberg, Elin; Arvidsson-Segerkvist, Katarina; Karlsson, Anders H.; Ólafsdóttir, Aðalheiður; Hilmarsson, Óli Þór; Gudjónsdóttir, María; Þorkelsson, Guðjón; Faculty of Food Science and Nutrition
Two slaughter systems for lambs and their effects on meat quality in terms of texture, colour and sensory attributes were compared. The slaughter systems differed in methods for controlling rigor mortis and carcass chilling. One slaughter system (large-scale) used electrical stimulation and fast chilling of carcasses, while the other system (small-scale) did not use electrical stimulation and applied slower chilling, with carcass temperature decreasing over a longer period after slaughter. Ten pairs of ram lamb twins were selected, and one of each pair was slaughtered at the large-scale abattoir and the other at the small-scale abattoir. Carcass weight, conformation, fatness, pH and temperature were recorded. Musculus longissimus thoracis et lumborum was analysed for colour, cooking loss, Warner–Bratzler shear force and sensory attributes. For meat quality attributes, the only differences were found in meat colour L* (lightness; p = 0.0073), sensory attribute “appearance colour” (p = 0.0089) and “fatty flavour” (p = 0.0554). Meat from the small-scale abattoir was darker in colour and had a more fatty flavour than the meat from the large-scale abattoir. For sensory attributes (apart from colour), no significant differences were found between the two abattoir systems.