Now showing items 281-300 of 4870

    • ADNet++: A few-shot learning framework for multi-class medical image volume segmentation with uncertainty-guided feature refinement 

      Hansen, Stine; Gautam, Srishti; Salahuddin, Suaiba Amina; Kampffmeyer, Michael Christian; Jenssen, Robert (Journal article; Tidsskriftartikkel, 2023-08-02)
      A major barrier to applying deep segmentation models in the medical domain is their typical data-hungry nature, requiring experts to collect and label large amounts of data for training. As a reaction, prototypical few-shot segmentation (FSS) models have recently gained traction as data-efficient alternatives. Nevertheless, despite the recent progress of these models, they still have some essential ...
    • Understanding the Influence of Lewis Acids on CO2 Hydrogenation: The Critical Effect Is on Formate Rotation 

      Pavlovic, Ljiljana; Hopmann, Kathrin Helen (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-11)
      Lewis acids (LAs) have been shown to accelerate hydrogenation of C0<sub>2</sub>, but the underlying mechanistic details remain to be elucidated. We have employed computational methods to investigate how LAs affect CO<sub>2</sub> hydrogenation with a range of known metal-hydrides (L<sub>n</sub>Ir–H, L<sub>n</sub>Ru–H, L<sub>n</sub>Mn–H, L<sub>n</sub>Co–H). Our results show that LAs can alter the ...
    • The Transition from Unfolded to Folded G-Quadruplex DNA Analyzed and Interpreted by Two-Dimensional Infrared Spectroscopy 

      Soenarjo, A Larasati; Lan, Zhihao; Sazanovich, Igor V.; Chan, Yee San; Ringholm, Magnus; Jha, Ajay; Klug, David R. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-08-30)
      A class of DNA folds/structures known collectively as G-quadruplexes (G4) commonly forms in guanine-rich areas of genomes. G4-DNA is thought to have a functional role in the regulation of gene transcription and telomerase-mediated telomere maintenance and, therefore, is a target for drugs. The details of the molecular interactions that cause stacking of the guanine-tetrads are not well-understood, ...
    • GNSS Scintillations in the Cusp, and the Role of Precipitating Particle Energy Fluxes 

      Ivarsen, Magnus Fagernes; Jin, Yaqi; Spicher, Andres; St-Maurice, Jean-Pierre; Park, Jaeheung; Billett, Daniel (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-16)
      Using a large data set of ground-based GNSS scintillation observations coupled with in situ particle detector data, we perform a statistical analysis of both the input energy flux from precipitating particles, and the observed occurrence of density irregularities in the northern hemisphere cusp. By examining trends in the two data sets relating to geomagnetic activity, we conclude that observations ...
    • Bianchi type cosmological models in f(T) tele-parallel gravity 

      van den Hoogen, Robert; Coley, Alan; McNutt, David Duncan (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-12)
      Symmetry assumptions on the geometrical framework have provided successful mechanisms to develop physically meaningful solutions to many problems. In tele-parallel gravity, invariance of the frame and spin-connection under a group of motions defines an affine symmetry group. Here, we assume there exists a three-dimensional group of affine symmetries acting simply transitively on a spatial hypersurface ...
    • Automated tilt compensation in acoustic microscopy 

      Gupta, Shubham Kumar; Habib, Anowarul; Kumar, Prakhar; Melandsø, Frank; Ahmad, Azeem (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-09-12)
      Scanning acoustic microscopy (SAM) is a potent and nondestructive technique capable of producing three-dimensional topographic and tomographic images of specimens. This is achieved by measuring the differences in time of flight (ToF) of acoustic signals emitted from various regions of the sample. The measurement accuracy of SAM strongly depends on the ToF measurement, which is affected by tilt in ...
    • Use of a Data-Sharing System During Diabetes Consultations 

      Bradway, Meghan; Muzny, Miroslav; Årsand, Eirik (Journal article; Tidsskriftartikkel; Peer reviewed, 2023)
      Patient-gathered self-management data and shared decision-making are touted as the answer to improving an individual’s health situation as well as collaboration between patients and their providers leading to more effective treatment plans. However, there is a gap between this ideal and reality – a lack of data-sharing technology. Here, we present the impact that the FullFlow System for sharing ...
    • Real-Time Ship Draft Measurement and Optimal Estimation Using Kalman Filter 

      Dhar, Sushmit; Khawaja, Hassan Abbas (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-02)
      Ship operators typically depend on the visual method for draft reading, which may lead to errors or approximations, and it further introduces draft survey calculation errors and can not provide continuous updates. Ensuring accurate real-time ship draft measurement becomes crucial for enhancing navigational safety, optimizing vessel performance, and achieving precise cargo and consumable measurements. ...
    • View it like a radiologist: Shifted windows for deep learning augmentation of CT images 

      Østmo, Eirik Agnalt; Wickstrøm, Kristoffer; Radiya, Keyur; Kampffmeyer, Michael; Jenssen, Robert (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-23)
      Deep learning has the potential to revolutionize medical practice by automating and performing important tasks like detecting and delineating the size and locations of cancers in medical images. However, most deep learning models rely on augmentation techniques that treat medical images as natural images. For contrast-enhanced Computed Tomography (CT) images in particular, the signals producing the ...
    • Associations and predictive power of dietary patterns on metabolic syndrome and its components 

      Moe, Åse Mari; Ytterstad, Elinor; Hopstock, Laila Arnesdatter; Løvsletten, Ola; Carlsen, Monica Hauger; Sørbye, Sigrunn Holbek (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-31)
      Background and aims: Metabolic syndrome (MetS) defines important risk factors in the development of cardiovascular diseases and other serious health conditions. This study aims to investigate the influence of different dietary patterns on MetS and its components, examining both associations and predictive performance.<p> <p>Methods and results: The study sample included 10,750 participants from ...
    • On mechanisms for high-frequency pump-enhanced optical emissions at 557.7 and 630.0gnm from atomic oxygen in the high-latitude F-region ionosphere 

      Leyser, Thomas B.; Sergienko, Tima; Brändström, Urban; Gustavsson, Björn Johan; Rietveld, Michael T. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-13)
      The EISCAT (European Incoherent Scatter Scientific Association) Heating facility was used to transmit powerful high-frequency (HF) electromagnetic waves into the Fregion ionosphere to enhance optical emissions at 557.7 and 630.0 nm from atomic oxygen. The emissions were imaged by several stations of ALIS (Auroral Large Imaging System) in northern Sweden, and the EISCAT UHF incoherent scatter radar ...
    • Impact of the Nares Strait sea ice arches on the long-term stability of the Petermann Glacier ice shelf 

      Prakash, Abhay; Zhou, Qin; Hattermann, Tore; Kirchner, Nina (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-12)
      One of the last remaining floating tongues of the Greenland ice sheet (GrIS), the Petermann Glacier ice shelf (PGIS), is seasonally shielded from warm Atlantic water (AW) by the formation of sea ice arches in the Nares Strait. However, continued decline of the Arctic sea ice extent and thickness suggests that arch formation is likely to become anomalous, necessitating an investigation into ...
    • Structure/function studies of the NAD<sup>+</sup>-dependent DNA ligase from the poly-extremophile Deinococcus radiodurans reveal importance of the BRCT domain for DNA binding 

      Fernandes, Andreia; Williamson, Adele Kim; Matias, Pedro M.; Moe, Elin (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-09-15)
      Bacterial NAD<sup>+</sup>-dependent DNA ligases (LigAs) are enzymes involved in replication, recombination, and DNA-repair processes by catalyzing the formation of phosphodiester bonds in the backbone of DNA. These multidomain proteins exhibit four modular domains, that are highly conserved across species, with the BRCT (breast cancer type 1 C-terminus) domain on the C-terminus of the enzyme. In ...
    • Discriminative multimodal learning via conditional priors in generative models 

      Andrade Mancisidor, Rogelio; Kampffmeyer, Michael Christian; Aas, Kjersti; Jenssen, Robert (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-02)
      Deep generative models with latent variables have been used lately to learn joint representations and generative processes from multi-modal data, which depict an object from different viewpoints. These two learning mechanisms can, however, conflict with each other and representations can fail to embed information on the data modalities. This research studies the realistic scenario in which all ...
    • Security of Supply: A National or European Competence? 

      Tuominen, Tomi; Halonen, Kirsi-Maria; Salminen, Mirva Miia Tuulikki (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-16)
      Security of supply refers to governmental policies that aim to secure the availability of critical products at all times. The COVID-19 pandemic brought to fore the importance of such policies, as suddenly there was an overwhelming need for critical medical supplies that the markets were not able to fulfil. Following the pandemic, the EU has started to construct its own security of supply policy, ...
    • Local Oxidation States in {FeNO}<sup>6-8</sup> Porphyrins: Insights from DMRG/CASSCF-CASPT2 Calculations 

      Phung, Quan Manh; Nam, Ho Ngoc; Ghosh, Abhik (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-27)
      A first DMRG/CASSCF–CASPT2 study of a series of paradigmatic {FeNO}<sup>6</sup>, {FeNO}<sup>7</sup>, and {FeNO}<sup>8</sup> heme–nitrosyl complexes has led to substantial new insight as well as uncovered key shortcomings of the DFT approach. By virtue of its balanced treatment of static and dynamic correlation, the calculations have provided some of the most authoritative information available to ...
    • Cavity-Free Continuum Solvation: Implementation and Parametrization in a Multiwavelet Framework 

      Gerez Sazo, Gabriel Adolfo; Remigio Eikås, Roberto Di; Jensen, Stig Rune; Bjørgve, Magnar; Frediani, Luca (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-18)
      We present a multiwavelet-based implementation of a quantum/classical polarizable continuum model. The solvent model uses a diffuse solute–solvent boundary and a position-dependent permittivity, lifting the sharp-boundary assumption underlying many existing continuum solvation models. We are able to include both surface and volume polarization effects in the quantum/classical coupling, with guaranteed ...
    • A Theoretical Search for Stable Terminal Carbides 

      Ghosh, Abhik; Conradie, Jeanet (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-20)
      xploratory scalar-relativistic density functional theory (B3LYP*-D3/ZORA-STO-TZ2P) calculations have been used to examine the stability and bonding of pseudotetrahedral Group 8 (Fe, Ru, and Os) and Group 9 (Co, Rh, and Ir) terminal carbide complexes with dδ4 ground states and tripodal tris(N-heterocyclic-carbene) supporting ligands. The calculations predict relatively low adiabatic ionization ...
    • Sub-ppm Methane Detection with Mid-Infrared Slot Waveguides 

      Yallew, Henock Demessie; Vlk, Marek; Datta, Anurup; Alberti, Sebastian; Zakoldaev, Roman A.; Høvik, Jens; Aksnes, Astrid; Jagerska, Jana (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-21)
      Hybrid integration of photonic chips with electronic and micromechanical circuits is projected to bring about miniature, but still highly accurate and reliable, laser spectroscopic sensors for both climate research and industrial applications. However, the sensitivity of chip-scale devices has been limited by immature and lossy photonic waveguides, weak light–analyte interaction, and etalon effects ...
    • Machine learning assisted multifrequency AFM: Force model prediction 

      Elsherbiny, Lamiaa; Santos Hernandez, Sergio; Gadelrab, Karim; Olukan, Tuza; Font, Josep; Barcons, Victor; Chiesa, Matteo (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-05)
      Multifrequency atomic force microscopy (AFM) enhances resolving power, provides extra contrast channels, and is equipped with a formalism to quantify material properties pixel by pixel. On the other hand, multifrequency AFM lacks the ability to extract and examine the profile to validate a given force model while scanning. We propose exploiting data-driven algorithms, i.e., machine learning packages, ...