Sökning: "extinction"

Visar resultat 26 - 30 av 267 avhandlingar innehållade ordet extinction.

  1. 26. The Amygdala, Fear and Reconsolidation : Neural and Behavioral Effects of Retrieval-Extinction in Fear Conditioning and Spider Phobia

    Författare :Johannes Björkstrand; Mats Fredrikson; Emily Holmes; Uppsala universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Fear conditioning; phobia; memory reconsolidation; retrieval-extinction; exposure therapy; amygdala; fMRI; Psychology; Psykologi;

    Sammanfattning : The amygdala is crucially involved in the acquisition and retention of fear memories. Experimental research on fear conditioning has shown that memory retrieval shortly followed by pharmacological manipulations or extinction, thereby interfering with memory reconsolidation, decreases later fear expression. LÄS MER

  3. 27. Retrieval of equivalent currents by the use of an integral representation and the extinction theorem --- radome applications

    Författare :Kristin Persson; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; extinction theorem; inverse source problem; integral representation; radome diagnosis; near-field transformation;

    Sammanfattning : The aim of this thesis is to solve an inverse source problem. The approach is based on an integral representation together with the extinction theorem. Both a scalar and a full-wave integral representation are implemented and solved by a Method of Moment procedure. LÄS MER

  4. 28. Sources of Dust Extinction in Type Ia Supernovae : Measurements and constraints from X-rays to the Infrared

    Författare :Joel Johansson; Edvard Mörtsell; Ariel Goobar; Rahman Amanullah; Bruno Leibundgut; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; supernovae; interstellar dust; circumstellar dust; cosmology; fysik; Physics;

    Sammanfattning : The use of Type Ia supernovae (SNe Ia) as distance indicators is essential for studying the expansion history of the Universe and for exploring the nature of dark energy. However, a lack of understanding of the progenitor systems and the empirically derived colour-brightness corrections represent severe limitations for SNe Ia as cosmological probes. LÄS MER

  5. 29. Dispersion relations for extinction of acoustic and electromagnetic waves

    Författare :Christian Sohl; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis deals with physical limitations on scattering and absorption of acoustic and electromagnetic waves. A general dispersion relation for the extinction cross section of such waves is derived from the holomorphic properties of the scattering amplitude in the forward direction. LÄS MER

  7. 30. Mammal extinction and climate change - learning from the past

    Författare :Veronica Nyström; Stockholms universitet; []
    Nyckelord :;

    Sammanfattning : .... LÄS MER