Sökning: "APEX"

Visar resultat 1 - 5 av 76 avhandlingar innehållade ordet APEX.

  1. 1. THz Vector Beam Measurement System for APEX Instrument SHeFI and Microwave Cryogenic Low Noise Amplifier Design

    Författare :Olle Nyström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vector measurements; mm- and submm-wave optics; LNA; radio astronomy; cryogenic amplifier; APEX; InP HEMT; Gaussian beam;

    Sammanfattning : This licentiate thesis describes results of the author’s work on development of THz vector beam measurement system and microwave cryogenic low-noise amplifier.The first part, and the main focus, of the thesis covers the vector beam measurement system for frequency range 210-500 GHz developed to characterize/verify the cold opticsof the APEX instrument SHeFI. LÄS MER

  3. 2. Anthropogenic impact on predator guilds and ecosystem processes : Apex predator extinctions, land use and climate change

    Författare :Marianne Pasanen Mortensen; Bodil Elmhagen; Francisco Palomares; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Mesopredators; apex predators; top-down; bottom-up; interspecific killing; red fox; Eurasian lynx; grey wolf; wolverine; productivity; winter severity; cropland; zoologisk ekologi; Animal Ecology;

    Sammanfattning : Humans affect ecosystems by changing species compositions, landscape and climate. This thesis aims to increase our understanding of anthropogenic effects on mesopredator abundance due to changes in apex predator status, landscape and climate. LÄS MER

  4. 3. Pathogenesis and Cell Biology of the Salmon Parasite Spironucleus salmonicida

    Författare :Ásgeir Ástvaldsson; Staffan Svärd; Jon Jerlström-Hultqvist; Scott Dawson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Diplomonads; Spironucleus; Giardia; genome; annexin; oxygen stress; APEX; pathology;

    Sammanfattning : Spironucleus species are classified as diplomonad organisms, diverse eukaryotic flagellates found in oxygen-deprived environments. Members of Spironucleus are parasitic and can infect a variety of hosts, such as mice and birds, while the majority are found to infect fish. LÄS MER

  5. 4. Radioastronomy Instrumentation for Herschel and APEX Projects

    Författare :Miroslav Pantaleev; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; beam measurements; quasioptics; optical alignment; submillimeter; HEB mixer;

    Sammanfattning : This thesis presents work done in developing instrumentation for sub-mm radio astronomyprojects.The first part covers Gaussian beam measurements for the Heterodyne Instrument for Far-Infrared (HIFI) of the Herschel Space Observatory project by the European Space Agency. LÄS MER

  7. 5. Ecology and evolution of tolerance in two cruciferous species

    Författare :Elin Boalt; Kari Lehtilä; Johan Ehrlén; Julia Koricheva; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; herbivory; tolerance; methodology; Raphanus raphanistrum; Cardamine pratensis; folivory; apex removal; plant competition; ploidy levels; herbivore pressure; Other biology; Övrig biologi; växtekologi; Plant Ecology;

    Sammanfattning : Tolerance to herbivory is the ability of plants to maintain fitness in spite of damage. The goal of this thesis is to investigate the genetic variation and expression of tolerance within species, determine whether and in what conditions tolerance has negative side-effects, and how tolerance is affected by different ecological factors. LÄS MER