Sökning: "existent"

Visar resultat 11 - 15 av 99 avhandlingar innehållade ordet existent.

  1. 11. Magnetic map sense in animals: effects of geographic and magnetic displacements

    Författare :Jannika Boström; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Oenanthe oenanthe; skylight polarization; geomagnetic map; geomagnetic field; endogenous migration programme; migratory fuelling; orientation; animal navigation;

    Sammanfattning : Migration research is a large and diverse field and in my thesis I have focused on the impact of geomagnetic cues on animal orientation, navigation and migratory fuelling. Several animal species from widely different taxa possess the ability to sense and make use of geomagnetic information during migratory or homing events. LÄS MER

  3. 12. Electronic structure and exchange interactions from ab initio theory : New perspectives and implementations

    Författare :Ramon Cardias Alves de Almeida; Olle Eriksson; Anders Bergman; Attila Szilva; R. B. Muniz; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ab initio; exchange interactions; non-collinear magnetism; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis, the magnetic properties of several materials were investigated using first principle calculations. The ab initio method named real space linear muffin-tin orbitals atomic sphere approximation (RS-LMTO-ASA) was used to calculate the electronic structure and magnetic properties of bulk systems, surface and nanostructures adsorbed on surfaces. LÄS MER

  4. 13. Risk stratification in cardiac surgery: Algorithms and applications

    Författare :Johan Nilsson; Thoraxkirurgi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Surgery; orthopaedics; traumatology; Kardiovaskulära systemet; Cardiovascular system; Cardiac surgery; Statistics; Artificial neural networks; Resource utilization; Mortality; Risk factors; Kirurgi; ortopedi; traumatologi;

    Sammanfattning : The aims of this research was to compare different risk score algorithms with regard to their validity to predict 30-day and one-year mortality after open-heart surgery, to evaluate if the preoperative risk stratification model EuroSCORE predicts the different components of resource utilization in cardiac surgery, and to systematically evaluate the accuracy and performance of artificial neural networks (ANNs) to select and rank the most important risk factors for operative mortality in open-heart surgery. Preoperative evaluation of the surgical risk is an important component in cardiac surgery. LÄS MER

  5. 14. Computational Atomic Structures Toward Heavy Element Research

    Författare :Sacha Schiffmann; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atoms; electron correlation; relativity; Quantum mechanics; calculations; natural orbitals; isotope shifts; hyperfine structures; transition parameters; Landé g factor; Fysicumarkivet A:2021:Schiffmann;

    Sammanfattning : We are interested in complex electronic structures of various atomic and ionics systems. We use an ab initioapproach, the multiconfigurational Dirac-Hartree-Fock (MCDHF), to compute atomic structures and properties. LÄS MER

  7. 15. Physical activity in the severely obese : studies on measurement and promotion

    Författare :Erik Hemmingsson; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :;

    Sammanfattning : Background: The amount and quality of evidence on how to effectively promote physical activity (PA) is low compared to what is known about the health effects of regular PA, especially in obese individuals. Aim : To evaluate the role of social support to promote walking in severely obese outpatients. LÄS MER