Fakultet for naturvitenskap og teknologi: Nye registreringer
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The Departure from Mixed-Layer Similarity During the Afternoon Decay of Turbulence in the Free-Convective Boundary Layer: Results from Large-Eddy Simulations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-21)This study analyses the departure of the velocity-variances profiles from their quasi-steady state described by the mixed-layer similarity, using large-eddy simulations with different prescribed shapes and time scales of the surface kinematic heat flux decay. Within the descriptive frames where the time is tracked solely by the forcing time scale (either constant or time-dependent) describing the ... -
Contrasting the phospholipid profiles of two neoplastic cell lines reveal a high PC:PE ratio for SH-SY5Y cells relative to A431 cells
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-14)Lipids have been implicated in Parkinson's Disease (PD). We therefore studied the lipid profile of the neuroblastoma SH-SY5Y cell line, which is used extensively in PD research and compared it to that of the A431 epithelial cancer cell line. We have isolated whole cell extracts (WC) and plasma membrane (PM) fractions of both cell lines. The isolates were analyzed with 31P NMR. We observed a significant ... -
Extreme Horizontal Wind Perturbations in the Mesosphere and Lower Thermosphere Over South America Associated With the 2022 Hunga Eruption
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-13)On 15 January 2022, the Hunga volcano produced a massive explosion that generated perturbations in the entire atmosphere. Nonetheless, signatures in the mesosphere and lower thermosphere (MLT) have been challenging to identify. We report MLT horizontal wind perturbations using three multistatic specular meteor radars on the west side of South America (spanning more than 3,000 km). The most ... -
MRNG: Accessing Cosmic Radiation as an Entropy Source for a Non-Deterministic Random Number Generator
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-26)Privacy and security require not only strong algorithms but also reliable and readily available sources of randomness. To tackle this problem, one of the causes of single-event upsets is the utilization of a non-deterministic entropy source, specifically ultra-high energy cosmic rays. An adapted prototype based on existing muon detection technology was used as the methodology during the experiment ... -
Biochemical and structural characterisation of a family GH5 cellulase from endosymbiont of shipworm P. megotara
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-04)Background Cellulases play a key role in the enzymatic conversion of plant cell-wall polysaccharides into simple and economically relevant sugars. Thus, the discovery of novel cellulases from exotic biological niches is of great interest as they may present properties that are valuable in the biorefning of lignocellulosic biomass. Results We have characterized a glycoside hydrolase 5 (GH5) domain ... -
Sea Ice Remote Sensing—Recent Developments in Methods and Climate Data Sets
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-03)Sea ice monitoring by polar orbiting satellites has been developed over more than four decades and is today one of the most well-established applications of space observations. This article gives an overview of data product development from the first sensors to the state-of-the-art regarding retrieval methods, new products and operational data sets serving climate monitoring as well as daily operational ... -
Fit-Twin: A Digital Twin of a User with Wearables and Context as Input for Health Promotion
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023)Digital health contributes to health promotion by empowering the user with the holistic view of their health. Health promotion is to enable the user to take control over their health. The availability of wearables has contributed to the shift in healthcare, that is more connected, predictive, and proactive. Proactive in healthcare is to predict and prevent a situation, beforehand. This shift in ... -
Dielectric nanoantennas and metasurfaces for optical trapping
(Doctoral thesis; Doktorgradsavhandling, 2023-09-14)Analysis of biological nanoparticles in medical sciences is very promising, as it can reveal groundbreaking information about disease mechanisms, potentially leading to innovative and more effective treatment strategies. The existing methods used for analyzing biological nanoparticles come with several limitations, involving extensive sample preparation, and giving limited information about the ... -
Petrogenesis and Geodynamic Significance of Xenolithic Eclogites
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-15)Kimberlite-borne xenolithic eclogites, typically occurring in or near cratons, have long been recognized as remnants of Precambrian subducted oceanic crust that have undergone partial melting to yield granitoids similar to the Archaean continental crust. While some eclogitized oceanic crust was emplaced into cratonic lithospheres, the majority was deeply subducted to form lithologic and geochemical ... -
Life cycle emission and cost assessment for LNG-retrofitted vessels: the risk and sensitivity analyses under fuel property and load variations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-13)There are various energy efficiency and emission reduction regulations enforced by the national and international maritime authorities for the shipping industry to adopt greener technologies. In this light, LNG-fueled vessels can be a promising alternative for ocean going diesel operated ships. It will be more beneficial if the price of LNG is lower than diesel to make that an economically viable ... -
Recolonization and recovery of an Arctic benthic community subject to mine-tailings deposits
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-22)Deposition of large volumes of mine tailings takes place in several Norwegian fjords, but the impacts on marine ecosystems have received relatively little scientific attention. At a 40 + − year old tailing deposition area for a copper mine in the Arctic fjord Repparfjorden, we investigated both short-term colonization of mine tailingscontaminated sediments through a field experiment, and the present ... -
Single-Molecule Sizing through Nanocavity Confinement
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-24): An approach relying on nanocavity confinement is developed in this paper for the sizing of nanoscale particles and single biomolecules in solution. The approach, termed nanocavity diffusional sizing (NDS), measures particle residence times within nanofluidic cavities to determine their hydrodynamic radii. Using theoretical modeling and simulations, we show that the residence time of particles ... -
Absence of photophysiological response to iron addition in autumn phytoplankton in the Antarctic sea-ice zone
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-31)he high nutrient–low chlorophyll condition of the Southern Ocean is generally thought to be caused by the low bioavailability of micronutrients, particularly iron, which plays an integral role in phytoplankton photosynthesis. Nevertheless, the Southern Ocean experiences seasonal blooms that generally initiate in austral spring, peak in summer, and extend into autumn. This seasonal increase in primary ... -
“Here, I will stay until I die”—exploring the relationship between place attachment, risk perception, and coping behavior in two small Norwegian communities
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-08-25)This empirical study explores the interplay between place attachment, risk perception, and coping behavior, within two small Norwegian communities exposed to flash flooding. Through a mixed-methods narrative approach, we found that most of our respondents exhibited positive attachment to their communities, aligning with previous studies in rural settings. Using a conceptual model of place attachment ... -
Solved and unsolved riddles about low-latitude daytime valley region plasma waves and 150-km echoes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-27)The Earth’s atmosphere near both the geographic and magnetic equators and at altitudes between 120 and 200 km is called the low-latitude valley region (LLVR) and is among the least understood regions of the ionosphere/thermosphere due to its complex interplay of neutral dynamics, electrodynamics, and photochemistry. Radar studies of the region have revealed puzzling daytime echoes scattered from ... -
Temporal evolution of under-ice meltwater layers and false bottoms and their impact on summer Arctic sea ice mass balance
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-31)Low-salinity meltwater from Arctic sea ice and its snow cover accumulates and creates under-ice meltwater layers below sea ice.These meltwater layers can result in the formation of new ice layers, or false bottoms, at the interface of this low-salinity meltwater and colder seawater. As part of the Multidisciplinary drifting Observatory for the Study of the Arctic Climate (MOSAiC), we used a ... -
User-Aware Conflict Resolution
(Master thesis; Mastergradsoppgave, 2023-06-26)A large-scale system that prioritizes high availability over extensive synchroniza- tion must make a design trade-off and implement a weaker form of consistency. Conflict-free Replicated Data Types(CRDTs) can enable replicas in the sys- tem to communicate asynchronously and achieve strong eventual consistency. SynQLite aims to implement CRDTs on top of relational databases with its addition of ... -
Efficient Fuel Consumption Minimization for Green Vehicle Routing Problems using a Hybrid Neural Network-Optimization Algorithm
(Master thesis; Mastergradsoppgave, 2023-06-01)Efficient routing optimization yields benefits that extend beyond mere financial gains. In this thesis, we present a methodology that utilizes a graph convolutional neural network to facilitate the development of energy-efficient waste collection routes. Our approach focuses on a Waste company in Tromsø, Remiks, and uses real-life datasets, ensuring practicability and ease of implementation. In ... -
Improving the performance of a Conflict-Free Replicated Relational Database System
(Master thesis; Mastergradsoppgave, 2023-05-31)SynQLite is a relational database (RDB) built on SQLite. Using conflict-free replicated relations (CRR) to apply conflict-free replicated data types (CRDT) to augment the SQLite database. With SynQLite sites update their local replica without coordination from others sites, and sites converge once they have applied the same sets of updates. These sets of updates are fetched from the CRR and ... -
Wind resource assessment and siting for the expansion of Fakken wind park
(Master thesis; Mastergradsoppgave, 2023-05-31)Norway is anticipated to experience an energy deficit in the coming years, and one solution to address this issue is the implementation of new renewable energy sources. To mitigate the projected energy deficit, increased energy production is required. With its considerable wind potential, the country offers ample opportunities for wind energy development. Consequently, there is a growing demand for ...