Sökning: "transient evolution"

Visar resultat 6 - 10 av 62 avhandlingar innehållade orden transient evolution.

  1. 6. Towards Understanding of Selectivity & Enantioconvergence of an Epoxide Hydrolase

    Författare :Åsa Janfalk Carlsson; Mikael Widersten; Uwe T. Bornscheuer; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Epoxide hydrolase; Epoxide; Enantioselectivity; Regioselectivity; Enantioconvergence; Crystal structures; Biocatalysis; Immobilization; Transient kinetics; CASTing; Directed evolution; Biokemi; Biochemistry;

    Sammanfattning : Epoxide hydrolase I from Solanum tuberosum (StEH1) and isolated variants thereof has been studied for mapping structure-function relationships with the ultimate goal of being able to in silico predict modifications needed for a certain activity or selectivity. To solve this, directed evoultion using CASTing and an ISM approach was applied to improve selectivity towards either of the enantiomeric product diols from (2,3-epoxypropyl)benzene (1). LÄS MER

  2. 7. Quantum Coherence and Quantum-Vacuum Effects in Some Artificial Electromagnetic Media

    Författare :Jianqi Shen; Sailing He; Chris Phillips; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Quantum coherence; quantum vacuum; electromagnetically induced transparency; negative refractive index; artificial electromagnetic media; electric- and magnetic-dipole transitions; multilevel atomic vapors; transient evolution; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

    Sammanfattning : The author of this thesis concentrates his attention on quantum optical properties of some artificial electromagnetic media, such as quantum coherent atomic vapors (various multilevel electromagnetically induced transparency vapors) and negative refractive index materials, and suggests some possible ways to manipulate wave propagations inside the artificial electromagnetic materials based on quantum coherence and quantum vacuum effects. In Chapters 1 and 2, the author reviews the previous papers on quantum coherence as well as the relevant work such as electromagnetically induced transparency (EIT), atomic population trapping and their various applications. LÄS MER

  3. 8. Properties of Type Ia Supernovae : From the (intermediate) Palomar Transient Factory

    Författare :Seméli Papadogiannakis; Ariel Goobar; Rahman Amandius; Ulrich Feindt; Edward Baron; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Type Ia supernovae; cosmology; machine learning; fysik; Physics;

    Sammanfattning : Type Ia Supernovae (SNe) have been used to discover the accelerated expansion of the universe but many open questions remain unanswered. These include the stellar progenitor, extinction and possible systematic trends in the supernova brightness for different host galaxy environments or cosmic time. LÄS MER

  4. 9. Through the magnifying glass - The big small world of marine meiofauna : Morphology, species and evolution in Nemertodermatida

    Författare :Inga Meyer-Wachsmuth; Ulf Jondelius; Mark E Sidall; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Nemertodermatida; Acoelomorpha; morphology; CLSM; Phalloidin; musculature; DNA; cryptic species; species delimitation; dispersal; taxonomy; phylogenetics; IHC; nervous system; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : Nemertodermatida is a group of microscopic marine worm-like animals that live as part of the marine meiofauna in sandy or muddy sediments; one species lives commensally in a holothurian. These benthic worms were thought to disperse passively with ocean currents, resulting in little speciation and thus wide or even cosmopolitan distributions. LÄS MER

  5. 10. Forest-savanna transitions: Understanding adaptation and resilience of the tropical forest ecosystems using remote sensing

    Författare :Chandrakant Singh; Ingo Fetzer; Lan Wang-Erlandsson; Ruud van der Ent; Stefano Manzoni; Udita Sanga; Vivian Ribeiro; Stockholms universitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Environmental Sciences; miljövetenskap; Ecology and Evolution; ekologi och evolution; Hydrology; hydrologi;

    Sammanfattning : Climate and deforestation-induced changes in precipitation drive tropical forest-savanna transitions. However, precipitation alone provides a superficial understanding of the underlying mechanism behind these transitions. This is because our knowledge of how vegetation responds to changes in hydroclimate is fragmented. LÄS MER