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Open Access Publications from the University of California

Scholarly Works (5 results)

  • Article
  • Peer Reviewed
UC Santa Barbara Previously Published Works (2015)
  • 1 supplemental PDF
Cover page: Adaptive synergy between catechol and lysine promotes wet adhesion by surface salt displacement
  • Article
E-Research (2020)

Background: The judicious use of antimicrobials in the livestock industry has become a topic of increasing interest over the last few years. Bovine respiratory disease (BRD) is considered mainly a problem of feedlot cattle or dairy calves, but a survey on the use of antimicrobials in California cow-calf operations revealed that BRD is in the top three diseases that ranchers treat most frequently with antimicrobials. There are both viral and bacterial causative agents that are associated with BRD. The pathogenesis of these agents often depends on the immune status of the animals and stress is considered to play major role in exacerbating the problem. In cow-calf operations these stressors can be in the form of management procedures such as processing of calves where they may be castrated, vaccinated, receive ear tags or being branded. Weaning is another stressful event in the life of a calf where the effects can be synergized if the calf is also transported at the same time. Due to the climate and landscape in California, cattle are often transported to different pastures in the summer and winter to take advantage of availability of feed year-round in different parts of the state at different times of the year. Vaccination, immune modulation, improving immune status through mineral supplementation and good colostrum[1] can all play a role in prevention of the disease relative to transportation. In this review we explore the available literature for evidence of effective methods to prevent BRD in cattle in California after transportation.

Objectives:  The objective of this scoping review is to examine and describe the existing literature on methods for the prevention of BRD that can be implemented in cow-calf operations in California and therefore reduce the use of antimicrobials due to BRD.

Design: Primary research on prevention of BRD due to shipping stress will be considered for inclusion. The process for selection and inclusion of the studies will be reported in a flow chart according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). The results will be summarized in tables and charts describing study types, interventions and outcomes.

    Cover page: Protocol for a Scoping/Systematic Review: Scoping Review Prevention of Shipping Fever in cow-calf operations
    • Article
    • Peer Reviewed
    UC Santa Cruz Previously Published Works (2023)
    Dark matter is a key piece of the current cosmological scenario, with weakly interacting massive particles (WIMPs) a leading dark matter candidate. WIMPs have not been detected in their conventional parameter space (100 GeV ≲M χ ≲ 100 TeV), a mass range accessible with current Imaging Atmospheric Cherenkov Telescopes. As ultraheavy dark matter (UHDM; M χ ≳ 100 TeV) has been suggested as an underexplored alternative to the WIMP paradigm, we search for an indirect dark matter annihilation signal in a higher mass range (up to 30 PeV) with the VERITAS γ-ray observatory. With 216 hr of observations of four dwarf spheroidal galaxies, we perform an unbinned likelihood analysis. We find no evidence of a γ-ray signal from UHDM annihilation above the background fluctuation for any individual dwarf galaxy nor for a joint-fit analysis, and consequently constrain the velocity-weighted annihilation cross section of UHDM for dark matter particle masses between 1 TeV and 30 PeV. We additionally set constraints on the allowed radius of a composite UHDM particle.
      Cover page: Search for Ultraheavy Dark Matter from Observations of Dwarf Spheroidal Galaxies with VERITASCreative Commons 'BY' version 4.0 license
      • Article
      • Peer Reviewed
      UC Irvine Previously Published Works (2014)
      We present deep VERITAS observations of the blazar PKS 1424+240, along with contemporaneous Fermi Large Area Telescope, Swift X-ray Telescope, and Swift UV Optical Telescope data between 2009 February 19 and 2013 June 8. This blazar resides at a redshift of z ≥ 0.6035, displaying a significantly attenuated gamma-ray flux above 100 GeV due to photon absorption via pair-production with the extragalactic background light. We present more than 100 hr of VERITAS observations over three years, a multiwavelength light curve, and the contemporaneous spectral energy distributions. The source shows a higher flux of (2.1 ± 0.3) × 10-7 photons m-2 s -1 above 120 GeV in 2009 and 2011 as compared to the flux measured in 2013, corresponding to (1.02 ± 0.08) × 10-7 photons m-2 s-1 above 120 GeV. The measured differential very high energy (VHE; E ≥ 100 GeV) spectral indices are Γ = 3.8 ± 0.3, 4.3 ± 0.6 and 4.5 ± 0.2 in 2009, 2011, and 2013, respectively. No significant spectral change across the observation epochs is detected. We find no evidence for variability at gamma-ray opacities of greater than τ = 2, where it is postulated that any variability would be small and occur on timescales longer than a year if hadronic cosmic-ray interactions with extragalactic photon fields provide a secondary VHE photon flux. The data cannot rule out such variability due to low statistics. © 2014. The American Astronomical Society. All rights reserved..
        Cover page: DEEP BROADBAND OBSERVATIONS OF THE DISTANT GAMMA-RAY BLAZAR PKS 1424+240
        • Article
        • Peer Reviewed
        UC Berkeley Previously Published Works (2016)
        We describe and report the status of a neutrino-triggered program in IceCube that generates real-time alerts for gamma-ray follow-up observations by atmospheric-Cherenkov telescopes (MAGIC and VERITAS). While IceCube is capable of monitoring the whole sky continuously, high-energy gamma-ray telescopes have restricted fields of view and in general are unlikely to be observing a potential neutrino-flaring source at the time such neutrinos are recorded. The use of neutrino-triggered alerts thus aims at increasing the availability of simultaneous multi-messenger data during potential neutrino flaring activity, which can increase the discovery potential and constrain the phenomenological interpretation of the high-energy emission of selected source classes (e.g. blazars). The requirements of a fast and stable online analysis of potential neutrino signals and its operation are presented, along with first results of the program operating between 14 March 2012 and 31 December 2015.
          Cover page: Very high-energy gamma-ray follow-up program using neutrino triggers from IceCube
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