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Visar resultat 1 - 5 av 45 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Magnetic resonance imaging with ultrashort echo time as a substitute for X-ray computed tomography

   Författare :Adam Johansson; Tufve Nyholm; Karlsson Mikael; James Balter; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetic resonance imaging; computed tomography substitute; ultrashort echo time; parallel imaging; radial imaging; radiofysik; radiation physics;

   Sammanfattning : Radiotherapy dose calculations have evolved from simple factor based methods performed with pen and paper, into computationally intensive simulations based on Monte Carlo theory and energy deposition kernel convolution.Similarly, in the field of positron emission tomography (PET), attenuation correction, which was originally omitted entirely, is now a crucial component of any PET reconstruction algorithm. LÄS MER

3. 2. Quality assurance for magnetic resonance imaging (MRI) in radiotherapy

   Författare :Mary Adjeiwaah; Tufve Nyholm; Rob HN Tijssen; Umeå universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magnetic resonance imaging; Radiotherapy; geometric distortions; patient-induced susceptibilities MR-only; radiofysik; radiation physics;

   Sammanfattning : Magnetic resonance imaging (MRI) utilizes the magnetic properties of tissues to generate image-forming signals. MRI has exquisite soft-tissue contrast and since tumors are mainly soft-tissues, it offers improved delineation of the target volume and nearby organs at risk. LÄS MER

4. 3. Nano-Engineered Contrast Agents : Toward Multimodal Imaging and Acoustophoresis

   Författare :Satya V.V.N. Kothapalli; Dmitry Grishenkov; Lars-Åke Brodin; Andreas Michael Versluis; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nano-engineered microbubbles; SPION nanoparticles; Acoustic characterization of MBs; Fracturing mechanism of MBs; Opto-acoustics; Acoustophoresis; Physics; Fysik; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer; Teknik och hälsa; Technology and Health;

   Sammanfattning : Diagnostic ultrasound (US) is safer, quicker and cheaper than other diagnostic imaging modalities. Over the past two decades, the applications of US imaging has been widened due to the development of injectable, compressible and encapsulated microbubbles (MBs) that provide an opportunity to improve conventional echocardiographic imaging, blood flow assessment and molecular imaging. LÄS MER

5. 4. Direct observation of biomolecule adsorption and spatial distribution of functional groups in chromatographic adsorbent particles

   Författare :Anders Ljunglöf; Abraham Lenhoff; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Biotechnology; Confocal microscopy; confocal Raman spectroscopy; protein adsorption; ligand distribution; visualization; imaging; Bioteknik; Bioengineering; Bioteknik; Surface Biotechnology; ytbioteknik;

   Sammanfattning : Confocal microscopy has been used as a tool for studying adsorption of biomolecules to individual chromatographic adsorbent particles. By coupling a fluorescent dye to protein molecules, their penetration into single adsorbent particles could be observed visually at different times during batch uptake. LÄS MER

7. 5. The dynamic chromosphere : Results and techniques with an observational approach

   Författare :Carolina Robustini; Jorrit Leenaarts; Fernando Moreno Insertis; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sun; chromosphere; jets; sunspots; imaging; spectropolarimetry; Astronomy; astronomi;

   Sammanfattning : The chromosphere is a critical interface between the relatively cold photosphere and the hot corona. Its landscape is rich in very dynamic phenomena such as jets, spicules, and surges, which are thought to play an important role in the heating of the Sun’s upper atmosphere. LÄS MER