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Open Access Publications from the University of California

Scholarly Works (2 results)

  • Thesis
  • Peer Reviewed
UC Davis Electronic Theses and Dissertations (2024)

A solenoid was built and installed in an ultra-high vacuum environment which guides and condenses electrons from the output charge cloud of a microchannel plate amplifier into a high-intensity, condensed electron beam. A low-intensity electron signal was input into the signal amplifier, where the external magnetic field generated by the solenoid resulted in a higher flux of electrons reaching the electron detector. High-current hardware was developed which pulses the solenoid for 10-ms at a peak current of 14.2 A, generating a peak magnetic field of 285.2 Gauss. The applied magnetic field increases the dynamic range of the electron image, with the observed intensity range increasing by a factor of up to 3.95. The average image intensity increased by a factor of up to 15.0 while the solenoid was pulsed. For a fixed microchannel plate bias, the accelerating grid and phosphor imaging plate high-voltage biases were swept to characterize the beam under different experimental conditions. The raw intensity distributions of the beams were profiled and fit to Gaussian distributions. Beams under the different experimental biases were imaged, and ellipses were fit to their intensity distributions. One standard deviation above each sample’s mean intensity, the resultant beams had an average beam size of 82.3 mm2, ellipse ratio of 0.77, offset from the origin on 4.38 mm, and rotation of 130.5°. The different beam images were post-processed, analyzed, and overlayed relative to each other using computer-aided design software to illustrate the relative beam sizes and intensities on the phosphor screen.

    Cover page: Solenoid Design Enabling the Direct Electron Imaging of Microchannel Plate Amplifiers
    • Article
    • Peer Reviewed
    UC Davis Previously Published Works (2020)
    BACKGROUND: Brutons tyrosine kinase (BTK) is important in B-cell signalling. Efficacy has been reported for BTK inhibitors (BTKi) in human autoimmune diseases. Canine pemphigus foliaceus (cPF) is one of the most common canine autoimmune skin diseases. OBJECTIVES: To determine the safety and efficacy of the BTKi PRN1008 in the treatment of cPF. ANIMALS: Four privately owned dogs. METHODS AND MATERIALS: Four dogs diagnosed with PF were administered BTKi PRN1008. Initial dosages approximated to 15 mg/kg once daily, increased to twice daily if inadequate response was seen. Treatment continued for 20 weeks, attempting to decrease to every other day. Dogs were monitored with complete blood counts, serum biochemistry panels and urinalyses, and evaluated with a modified version of a validated human Pemphigus Disease Activity Index (cPDAI). Serum anti-desmocollin-1 (DSC-1) and desmoglein-1 (DSG-1) immunoglobulin (Ig)G titres were performed before and after the treatment period. Drug bound to target was measured in peripheral blood mononuclear cells (PBMC). RESULTS: All four dogs showed reduction in lesions and cPDAI score during the first two weeks of treatment. Three dogs continued to improve and sustained near complete remission by 20 weeks, at which point three responses were considered good and one fair. Final daily dosages were in the range 17-33 mg/kg. Anti-DSC-1 IgG titre decreased dramatically in one dog, was undetectable in two and was uninterpretable in one dog. No dogs had detectable IgG to DSG1. A possible adverse event occurred in one dog. CONCLUSIONS AND CLINICAL IMPORTANCE: BTKi PRN1008 monotherapy may have some beneficial effects in some cases of cPF.
      Cover page: Open trial of Brutons tyrosine kinase inhibitor (PRN1008) in the treatment of canine pemphigus foliaceus.
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