Sökning: "gradient"

Visar resultat 16 - 20 av 1260 avhandlingar innehållade ordet gradient.

  1. 16. Regulation of morphogen signalling during neural patterning in the Xenopus embryo

    Författare :Hooi Min Tan Grahn; Avdelningen för molekylärmedicin och genterapi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Suppressor-of-fused; Gli; β-Catenin; Neural; Xenopus; FGF; Signalling; HtrA1; RDH10; Retinol dehydrogenase; Retinoic acid; Spemann s organizer; Induction; Gradient;

    Sammanfattning : Morphogens such as Hedghog, Wnt, FGF, and retinoic acid are important signals whose concentrations need to be tightly regulated in the vertebrate embryo to ensure body axis development and formation of the central nervous system. We first show that the intracellular cytoplasmic protein XSufu acts as a dual regulator of Hedgehog (Hh) and Wnt signals during neural induction and patterning in the Xenopus embryo. LÄS MER

  3. 17. Is genetic diversity more important for terpene emissions than latitudinal adaptation? : Using genetically identical trees to better understand emission fluctuations across a European gradient

    Författare :Ylva van Meeningen; Institutionen för naturgeografi och ekosystemvetenskap; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; BVOC; English oak; European beech; Norway spruce; genetic diversity; European gradient;

    Sammanfattning : Biogenic volatile organic compounds (BVOCs) are trace gases other than CO2 and CH4 produced and emitted by the vegetation. The group consists of thousands of compounds in various shapes and sizes and with short atmospheric lifetimes. Some of the most common BVOC groups are called isoprene, monoterpenes and sesquiterpenes. LÄS MER

  4. 18. New Techniques for Estimation of Source Parameters : Applications to Airborne Gravity and Pseudo-Gravity Gradient Tensors

    Författare :Majid Beiki; Laust Pedersen; Mehrdad Bastani; Mark Pilkington; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Gravity gradient tensor; pseudo-gravity; magnetic field; eigenvector analysis; least squares algorithm; strike direction; source parameter estimation; analytic signal; Euler deconvolution; joint inversion; infinite dike model; geological contact model; Solid earth physics; Fasta jordens fysik; Geophysics with specialization in Solid Earth Physics; Geofysik med inriktning mot fasta jordens fysik;

    Sammanfattning : Gravity gradient tensor (GGT) data contains the second derivatives of the Earth’s gravitational potential in three orthogonal directions. GGT data can be measured either using land, airborne, marine or space platforms. LÄS MER

  5. 19. Microbial Ecosystem Functions Along the Steep Oxygen Gradient of the Landsort Deep, Baltic Sea

    Författare :Petter Thureborn; Sara Sjöling; Mats Grahn; Matthias Labrenz; Södertörns högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; microbial ecology; ecosystem functions; microbial community; bacteria; archaea; metagenomics; metatranscriptomics; oxygen gradient; hypoxia; sediment; Baltic Sea; Environmental Studies; Miljövetenskapliga studier; Östersjö- och Östeuropaforskning; Baltic and East European studies;

    Sammanfattning : Through complex metabolic interactions aquatic microbial life is essential as a driver of ecosystem functions and hence a prerequisite for sustaining plant and animal life in the sea and on Earth. Despite its ecological importance, infor­mation on the complexity of microbial functions and how these are related to environmental conditions is limited. LÄS MER

  7. 20. Diffusion MRI with generalised gradient waveforms : methods, models, and neuroimaging applications

    Författare :Deneb Boito; Evren Özarslan; Magnus Herberthson; Anders Eklund; Ida Blystad; Frederik Laun; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Diffusion; Diffusion MRI; Microstructure; Brain; White matter; Microscopic anisotropy; Constrained optimisation;

    Sammanfattning : The incessant, random motion of water molecules within biological tissues reveals unique information about the tissues’ structural and functional characteristics. Diffusion magnetic resonance imaging is sensitive to this random motion, and since the mid-1990s it has been extensively employed for studying the human brain. LÄS MER