Blar i tittel Fakultet for naturvitenskap og teknologi

Viser treff 3148-3167 av 4765

    • Paleo-methane emissions recorded in foraminifera near the landward limit of the gas hydrate stability zone offshore western Svalbard 

      Panieri, Giuliana; Graves, Carolyn; James, Rachel (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-02-26)
      We present stable isotope and geochemical data from four sediment cores from west of Prins Karls Forland (ca. 340 m water depth), offshore western Svalbard, recovered from close to sites of active methane seepage, as well as from shallower water depths where methane seepage is not presently observed. Our analyses provide insight into the record of methane seepage in an area where ongoing ocean ...

    • The Paleoarchean Buffalo River komatiites: Progressive melting of a single large mantle plume beneath the growing Kaapvaal craton 

      Netshidzivhe, Thendo; Tappe, Sebastian; Wilson, Allan H.; Ishikawa, Akira; Viljoen, Fanus (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-01)
      Several Archean granitoid-greenstone terranes are exposed on the southeastern Kaapvaal craton in South Africa, but they received little scientific attention compared to the archetypal greenstone belt successions of the Barberton Mountain Land at the eastern craton margin. This study reports on a detailed field and geochemical survey of the Buffalo River Greenstone Belt at the southern Kaapvaal craton ...

    • Paleobathymetric reconstructions of the SW Barents Seaway and their implications for Atlantic–Arctic ocean circulation 

      Lasabuda, Amando P. E.; Hanssen, Alfred; Laberg, Jan Sverre; Faleide, Jan Inge; Patton, Henry; Abdelmalak, Mohamed Mansour; Rydningen, Tom Arne; Kjølhamar, Bent (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-29)
      Unravelling past, large-scale ocean circulation patterns is crucial for deciphering the longterm global paleoclimate. Here we apply numerical modelling to reconstruct the detailed paleobathymetry-topography of the southwestern inlet of the Barents Seaway that presently connects the Atlantic and Arctic oceans. Subaerial topography was likely enough to block Atlantic Water from entering the Barents ...

    • Paleoceanographic development during the last deglaciation and Holocene, over the Bear Island slide scar, SW Barents Sea 

      Danielsen, Ida Kristin (Master thesis; Mastergradsoppgave, 2017-02-02)
      The investigated sediment core HH13-243 GC is located under the present flow of the warm and saline Atlantic Water (AW), but close to, glaciated continental margins. The core site is situated in an area that is sensitive to changes and reflects the paleoceanography of the northernmost Norwegian Sea and the Western Barents Sea. We investigated the changes in inflow of Atlantic water and the ...

    • Paleoceanographic development in Leirdjupet, during the last deglaciation 

      Tønnessen, Lasse Aase (Master thesis; Mastergradsoppgave, 2016-08-23)
      The focus of this master thesis is to investigate the paleoenvironmental and paleoceanography during the last deglaciation in Leirdjupet, a small submarine trough in the southwestern Barents Sea. The lower half of the piston corer HH15-1303PC has been investigated for the distribution pattern of benthic foraminifera faunas, ice rafted debris (IRD), lithology and oxygen and carbon isotopes covering; ...

    • Paleoceanographic Development in Nordfjord, North East Greenland, During the Mid- and Late Holocene 

      Skjelvan, Bjørnar Liland (Master thesis; Mastergradsoppgave, 2017-05-15)
      Sediment core HH13-012GC-TUNU, retrieved from Nordfjord, North-East Greenland, has been investigated in order to reconstruct the paleoceanographic development during the mid- and late Holocene. Nordfjord is one of three tributary fjords to Kaiser Franz Joseph Fjord, and Waltershausen Gletcher is located at its head. The fjord system is largely influenced by the Eastern Greenland Current. Most of ...

    • Paleoceanographic development in Storfjorden, Svalbard, during the deglaciation and Holocene: evidence from benthic foraminiferal records 

      Rasmussen, Tine Lander; Thomsen, Erik (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-08-07)
      Brines can have a profound influence on the relative abundance of calcareous and agglutinated foraminiferal faunas. Here we investigated the distribution of benthic foraminiferal species in four cores from a brine‐enriched environment in Storfjorden, Svalbard. Stratigraphically, the cores comprise the last 15 000 years. The purpose of the study was to reconstruct changes in the palaeoecology and ...

    • Paleoceanography of the NE North Atlantic during the Holocene 

      Groot, Diane (Doctoral thesis; Doktorgradsavhandling, 2014-09-26)
      This thesis aimed at enhancing our understanding of the oceanographic variability of the Nordic Seas during the last 11,000 years. The Nordic Seas are a key area within the Atlantic Meridional Overturning Circulation (AMOC), a process which helps to maintain the present mild climate of northwestern Europe through its meridional heat transport and plays an important role in global heat distribution. ...

    • Paleoceanography of the Northwestern Greenland Sea and Return Atlantic Current evolution, 35–4 kyr BP 

      Devendra, Dhanushka; Łącka, Magdalena; Telesiński, Maciej M.; Rasmussen, Tine Lander; Sztybor, Kamila; Zajączkowski, Marek (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-10)
      The flow of the Atlantic Water (AW) via the Return Atlantic Current (RAC) regulates the oceanographical conditions in the Northwestern (NW) Greenland Sea in the Fram Strait. As the intensity of the RAC might significantly influence both deep-water formation in the area and the stability of the Northeast Greenland Ice Sheet (NE GIS), knowledge of its variability in the past is important. Here we ...

    • Paleoenvironmental investigation of the northern flank of the Olga Basin (Barents Sea) during the Late Weichselian deglaciation 

      Patel, Jay (Master thesis; Mastergradsoppgave, 2018-06-11)
      Three gravity cores were collected from an unexplored site in the northern flank of the Olga Basin, Barents Sea. The lack of data from the central Barents Sea prompted this investigation and led to defining the evolution of the environment and ice sheet transitions over the Holocene. The three cores underwent benthic foraminiferal studies in combination with stable isotope analysis of (δ18O and δ ...

    • Palladium(0)-Catalyzed Cross-Couplings of 2-Bromophosphinine 

      Kostenko, Nataliya; Eriksson, Cecilia; Engqvist, Magnus; Villa Gonzalez, Susana; Bayer, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2013-05-21)
      A new Negishi-type cross-coupling of 2-bromophosphinine has been developed. The new method expands the scope of palladium-catalyzed couplings to monobromophosphinines, which have been considered as poor substrates so far. Moreover, aryl-, alkenyl-, and alkynylzinc bromides were found to be effective coupling partners.

    • Pan genome and CRISPR analyses of the bacterial fish pathogen Moritella viscosa 

      Karlsen, Christian; Hjerde, Erik; Klemetsen, Terje; Willassen, Nils Peder (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-20)
      Background: Winter-ulcer Moritella viscosa infections continue to be a significant burden in Atlantic salmon (Salmo salar L.) farming. M. viscosa comprises two main clusters that differ in genetic variation and phenotypes including virulence. Horizontal gene transfer through acquisition and loss of mobile genetic elements (MGEs) is a major driving force of bacterial diversification. To gain insight ...

    • Papirbretting som geometrisk verktøy Utforsket ved hjelp av Gröbner-basiser og anvendt i skoleundervisning 

      Eskeland, Ingar Wesenberg (Mastergradsoppgave; Master thesis, 2022-05-30)
      I over 2000 år har matematikere utforsket konstruksjoner med passer og linjal. Først i 1837 ble det bevist at disse konstruksjonene ikke kan løse problemer som er ekvivalent med å løse tredjegradsligninger, deriblant vinkeltredeling og kubens fordobling. 100 år senere fant Margharita Piazolla Beloch ut en konstruksjon som løser tredjegradsligninger. Hun brukte verken passer eller linjal, men ...

    • Parallelization of the Alternating-Least-Squares Algorithm With Weighted Regularization for Efficient GPU Execution in Recommender Systems 

      Kampffmeyer, Michael Christian (Master thesis; Mastergradsoppgave, 2015-06-15)
      Collaborative filtering recommender systems have become essential to many Internet services, providing, for instance, book recommendations at Amazon's online e-commerce service, music recommendation in Spotify and movie recommendation in Netflix. Matrix factorization and Restricted Boltzmann Machines (RBMs) are two popular methods for implementing recommender systems, both providing superior ...

    • Parameter-Free Extended Edit Distance 

      Muhammad Fuad, Muhammad Marwan (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      The edit distance is the most famous distance to compute the similarity between two strings of characters. The main drawback of the edit distance is that it is based on local procedures which reflect only a local view of similarity. To remedy this problem we presented in a previous work the extended edit distance, which adds a global view of similarity between two strings. However, the extended edit ...

    • Parasites from cod in two different localities, the Barents Sea and Øksfjord in the coastal region of northern Norway. A comparison 

      Løvland, Ann Beate (Master thesis; Mastergradsoppgave, 2017-06-29)
      Parasites have been given a prominent role in ecology because of their potential to influence ecosystem dynamics. Parasite-host interactions are important in understanding host population dynamics and ecological processes. The marine environment is the largest ecosystem in the world, and between the coastal realm and the open water realm exists great ecological variances. Because parasites encompass ...

    • Parid-GO A Personalised Augmented Reality Game to Reinforce Outdoor Physical Activity for People with Intellectual Disabilities 

      Sivakumar, Keerthana (Mastergradsoppgave; Master thesis, 2023-09-11)
      Parid-GO A Personalised Augmented Reality Game to Reinforce Outdoor Physical Activity for People with Intellectual Disabilities. This project aims to develope a dynamic content solution that are user centric. The rationale is that by allowing the participants to customize and use other themes, colors, etc., the participant will be more engaged and use the application more. Which in turn will increase ...

    • Paris-toppmøtet og spillet om CO2-kvotene 

      Rypdal, Kristoffer (Chronicle; Kronikk, 2015-11-25)

    • A Parsimonious Description and Cross-Country Analysis of COVID-19 Epidemic Curves 

      Rypdal, Kristoffer; Rypdal, Martin (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-06)
      In a given country, the cumulative death toll of the first wave of the COVID-19 epidemic follows a sigmoid curve as a function of time. In most cases, the curve is well described by the Gompertz function, which is characterized by two essential parameters, the initial growth rate and the decay rate as the first epidemic wave subsides. These parameters are determined by socioeconomic factors and ...

    • Partially spatially coherent digital holographic microscopy and machine learning for quantitative analysis of human spermatozoa under oxidative stress condition 

      Dubey, Vishesh Kumar; Popova, Daria; Ahmad, Azeem; Acharya, Ganesh; Basnet, Purusotam; Mehta, Dalip Singh; Ahluwalia, Balpreet Singh (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-05)
      Semen quality assessed by sperm count and sperm cell characteristics such as morphology and motility, is considered to be the main determinant of men’s reproductive health. Therefore, sperm cell selection is vital in assisted reproductive technology (ART) used for the treatment of infertility. Conventional bright field optical microscopy is widely utilized for the imaging and selection of sperm cells ...