Sökning: "diameter effect"

Visar resultat 21 - 25 av 280 avhandlingar innehållade orden diameter effect.

  1. 21. The effect of pressure afterload due to aortic coarctation on left ventricular function in children

    Författare :Haki Jashari; Michael Henein; Annika Rydberg; Katarina Hanséus; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Coarctation of the aorta; congenital aortic stenosis; left ventricle; myocardial deformation imaging; speckle tracking echocardiography; longitudinal strain; aorto-septal angle; children; kardiologi; Cardiology;

    Sammanfattning : Background:Coarctation of the aorta (CoA) is a congenital heart disease which represents a narrowing of the proximal descending aorta, hence increasing pressure afterload to the left ventricle (LV). Conventional treatment of native CoA is surgical repair, however potential recurrence or other related complications e.g. LÄS MER

  2. 22. Growth, Physics, and Device Applications of InAs-based Nanowires

    Författare :Linus Fröberg; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; field effect transistors; Low-dimensional structures; nanowires; chemical beam epitaxy; heterostructures; III-V; InP; InAs; quantum dots; gate all-around; wrap gate;

    Sammanfattning : This thesis is based on three different projects: 1) the epitaxial growth of nanowires using chemical beam epitaxy, 2) the study of electron transport through quantum dots and multiple quantum dots in nanowires at low temperature, and 3) the development of wrap gated nanowire field effect transistors. In the first part, a method of studying the diffusion of the source material on the substrate surface was developed. LÄS MER

  3. 23. Error reduction strategies for quantitative PET with focus on hybrid PET/MRI

    Författare :Elin Wallstén; Anne Larsson; Jan Axelsson; Katrine Riklund; Ronald Boellaard; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Positron emission tomography; PET; PET MR; PET MRI; medical imaging; partial-volume effect; attenuation correction; radiofysik; radiation physics;

    Sammanfattning : Positron Emission Tomography (PET) is an important tool for detection, staging and follow-up in a wide range of diseases, including cancer and neurological disorders. As a functional imaging tool, PET can visualize biological processes, where positron emitting radioactive isotopes are connected to molecules with different functions in the body. LÄS MER

  4. 24. Whiplash injury : a clinical, radiographic and psychological investigation

    Författare :Kurt Pettersson; Seppo Santavirta; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cervical spine; whiplash injury; MRI; personality traits; steroid therapy; sagittal canal diameter; chronic symptoms;

    Sammanfattning : Whiplash injury is a common and troublesome disorder and approximately 10-40 per cent of its victims develop chronic symptoms. The annual incidence is estimated at 1/1000 inhabitants and the prevalence at 1%. The cause of chronic symptoms after whiplash injury is still unknown and no effective treatment has been presented so far. LÄS MER

  5. 25. Microstructure Investigation of the Oxidation Process in Zircaloy-2 - The Effect of Intermetallic Particle Size

    Författare :Pia Tejland; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Zircaloy-2; STEM; HAADF; ADF; FIB; SEM; EDX; APT;

    Sammanfattning : Zirconium alloys are widely used in nuclear reactors as fuel cladding tubes because of their low thermal neutron capture cross-section, good corrosion properties and satisfactory mechanical properties. With an improved corrosion resistance the alloys could be used for much longer times in the reactors, increasing fuel burn-up and decreasing the amount of radioactive waste. LÄS MER