Fakultet for naturvitenskap og teknologi: Recent submissions
Now showing items 2381-2400 of 5361
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Resilience assessment of the transport corridor from Stokmarknes to Stockholm
(Master thesis; Mastergradsoppgave, 2019-08-01)Timely delivery of the required goods plays an important role in meeting the availability and reducing the downtime of Markets. Salmon transport logistics is affected in complex ways while operating in the Arctic, since the area is sparsely populated and has insufficient infrastructure. It is also greatly affected by the distinctive operational environment of the region, such as cold temperature, ... -
Cyclostratigraphic age constraining for Quaternary sediments in the Makarov Basin of the western Arctic Ocean using manganese variability
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-26)The Quaternary paleoenvironmental history of the Arctic Ocean remains uncertain, mainly due to the limited chronological constraints, especially beyond the 14C dating limits of accelerator mass spectrometry (AMS). The difficulty in establishing reliable chronostratigraphies is mainly attributed to low sedimentation rates and diagenetic sediment changes, resulting in very poor preservation of ... -
Late Quaternary depositional and glacial history of the Arliss Plateau off the East Siberian margin in the western Arctic Ocean
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-12-19)Sedimentary stratigraphy and facies analysis along with seismostratigraphic and multibeam bathymetrydata are used to reconstruct the last glacial impact on the Arliss Plateau (AP) and attendant sedimen-tation in the adjacent Chukchi Basin (CB) in the western Arctic Ocean off the East Siberian margin.Sediment core ARA02B/16B-GC from the AP lower slope captures glacier-related depositional historyduring ... -
Comment to “Neoproterozoic magmatic arc systems of the central Ribeira belt, SE-Brazil, in the context of the West-Gondwana pre-collisional history: A review”
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-25) -
Glucose Regulation for In-Silico Type 1 Diabetes Patients Using Reinforcement Learning
(Doctoral thesis; Doktorgradsavhandling, 2021-05-07)Type 1 diabetes is a metabolic disorder characterized by high blood glucose levels as a consequence of deficiency of the hormone insulin, requiring the patient to follow a strict personalized protocol of food intake, subcutaneous insulin administration as a lifelong treatment for the high blood glucose levels, and exercise. This condition leads to acute complications, damaging several organs and ... -
Ice-albedo tipping points in a diffusive energy-balance model with land and ocean
(Mastergradsoppgave; Master thesis, 2021-01-20)The ice-albedo feedback is associated with the nonlinearity in the climate system, due to the sudden change in albedo between ice-free and ice-covered surfaces. This nonlinearity can potentially cause abrupt and dramatic shifts in the climate, referred to as tipping points. It is also believed that this mechanism has contributed significantly to the precipitous losses of Arctic sea ice, which have ... -
Comparison Between Dielectric Inversion Results From Synthetic Aperture Radar Co- and Quad-Polarimetric Data via a Polarimetric Two-Scale Model
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-03)In this study, we compare the retrieval results for the dielectric properties of verified oil slick, acquired using airborne multifrequency synthetic aperture radar. A polarimetric two-scale model was used to invert the radar imagery by first employing solely the co-polarization channels, and then by employing the co-polarization channels in conjunction with the cross-polarization channels, and ... -
Geomorphology and surficial geology of the Femmilsjøen area, northern Spitsbergen
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-09)Climate change is amplified in the Arctic, and establishing baseline data for its current character is important. Here we present a map of the geomorphology of the Femmilsjøen area, Spitsbergen, northern Svalbard. The regional physiography is characterised by a low-relief, high elevation mountain plateau, its high-relief steep slopes, and low-relief coastal lowlands. The results indicate that glaciers ... -
A Polymer Magician: Professor Charlotte K. Williams
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-28)At Organometallics, the Editorial Team has been highlighting a number of scientists that we feel have had a profound impact on the field and perhaps also on ourselves. In this editorial, I wish to introduce another of our Pioneers and Influencers, Professor Charlotte K. Williams from Oxford University. Professor Williams works on three things I love: homogeneous metal catalysts, carbon dioxide, and ... -
Russia's Critical Infrastructure Policy: What do we Know About it?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-29)The article is an analytical state-of-the-art review of the Russian Federation’s critical infrastructure policy, starting from the 1990s but zooming in on the current situation. The article discusses what does critical infrastructure mean in the Russian context. It explores the country’s threat scenarios in this field, and asks what part is played by cyber security threats in this context. Further, ... -
Activity Game Avatar: A interactive exergame for people with intellectual disabilities.
(Mastergradsoppgave; Master thesis, 2021-03-01)Statistics from the World Health Organization (WHO) show clear indications that some groups in society have more significant struggles than others getting the recommended amount of physical activity. One of these groups is people with intellectual disabilities, which have different functioning resulting in different needs in terms of facilitation, accessibility, and usability. Many within this group ... -
Platelet ice under Arctic pack ice in winter
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-17)The formation of platelet ice is well known to occur under Antarctic sea ice, where subice platelet layers form from supercooled ice shelf water. In the Arctic, however, platelet ice formation has not been extensively observed, and its formation and morphology currently remain enigmatic. Here, we present the first comprehensive, long‐term in situ observations of a decimeter thick subice platelet ... -
ELM-HTM guided bio-inspired unsupervised learning for anomalous trajectory classification
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-23)Artificial intelligent systems often model the solutions of typical machine learning problems, inspired by biological processes, because of the biological system is faster and much adaptive than deep learning. The utility of bio-inspired learning methods lie in its ability to discover unknown patterns, and its less dependence on mathematical modeling or exhaustive training. In this paper, we propose ... -
How Does El Niño–Southern Oscillation Change Under Global Warming—A First Look at CMIP6
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-22)The latest generation of coupled models, the sixth Coupled Models Intercomparison Project (CMIP6), is used to study the changes in the El Niño–Southern Oscillation (ENSO) in a warming climate. For the four future scenarios studied, the sea surface temperature variability increases in most CMIP6 models, but to varying degrees. This increase is linked to a weakening of the east‐west temperature gradient ... -
Waveguide-based Excitation for High-throughput Imaging
(Doctoral thesis; Doktorgradsavhandling, 2021-03-24)Chip–based fluorescence imaging is an emerging field where the fluorophores in a sample are excited by the evanescent field generated by waveguides. The aim of this thesis is to explore how waveguide–based excitation can benefit super–resolution optical microscopy, as well as investigate other imaging and spectroscopic applications which can benefit from the same platform. For all imaging and ... -
Trapped Particle Motion In Magnetodisc Fields
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-13)The spatial and temporal characterization of trapped charged particle trajectories in magnetospheres has been extensively studied in dipole magnetic field structures. Such studies have allowed the calculation of spatial quantities, such as equatorial loss cone size as a function of radial distance, the location of the mirror points along particular field lines (<i>L</i>‐shells) as a function of the ... -
Vaccination criteria based on factors influencing COVID-19 diffusion and mortality
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-15)SARS-CoV-2 is highly contagious, rapidly turned into a pandemic, and is causing a relevant number of critical to severe life-threatening COVID-19 patients. However, robust statistical studies of a large cohort of patients, potentially useful to implement a vaccination campaign, are rare. We analyzed public data of about 19,000 patients for the period 28 February to 15 May 2020 by several mathematical ... -
Photonic-chip assisted correlative light and electron microscopy
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-07)Correlative light and electron microscopy (CLEM) unifies the versatility of light microscopy (LM) with the high resolution of electron microscopy (EM), allowing one to zoom into the complex organization of cells. Here, we introduce photonic chip assisted CLEM, enabling multi-modal total internal reflection fluorescence (TIRF) microscopy over large field of view and high precision localization of the ... -
In-Silico Evaluation of Glucose Regulation Using Policy Gradient Reinforcement Learning for Patients with Type 1 Diabetes Mellitus
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-11)In this paper, we test and evaluate policy gradient reinforcement learning for automated blood glucose control in patients with Type 1 Diabetes Mellitus. Recent research has shown that reinforcement learning is a promising approach to accommodate the need for individualized blood glucose level control algorithms. The motivation for using policy gradient algorithms comes from the fact that adaptively ... -
Biochemical characterization of ferric uptake regulator (Fur) from Aliivibrio salmonicida. Mapping the DNA sequence specificity through binding studies and structural modelling
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-09)Iron is an essential nutrient for bacteria, however its propensity to form toxic hydroxyl radicals at high intracellular concentrations, requires its acquisition to be tightly regulated. Ferric uptake regulator (Fur) is a metal-dependent DNA-binding protein that acts as a transcriptional regulator in maintaining iron metabolism in bacteria and is a highly interesting target in the design of new ...