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Open Access Publications from the University of California

Scholarly Works (30 results)

  • Article
  • Peer Reviewed
American Indian Culture and Research Journal , Volume 7, Issue 2 (1983)
It is said that during the American War of Independence the roll-call wampum, the sacred beads that designated where the representatives of the Six Nations of the Iroquois Confederacy grouped themselves about the council fires, was buried for safekeeping. After the war it was unearthed and reused when Sir Frederick Haldimand, the Governor of Quebec, granted members of the tribes an extensive tract of land on the banks of the Grand River in Ontario, Canada. Today the Six Nations Reserve near Brantford in Ontario is the largest of the Iroquois reservations and the only one that includes groups from all the Six Nations. These Indians are descendants of those who, as a result of their siding with the British at the time of the revolution, were forced to take refuge in Canada and were given in 1784 the Grand River lands. The arrangement which the Canadians call the Haldimand Deed is to this day regarded as a legitimate treaty by the Iroquois. The Iroquoian-speaking Peoples of the Northeast lived in a large expanse of territory stretching from Lake Nipissing in the present province of Ontario southward to the Susquehanna region of Pennsylvania. Their domain extended from the Adirondacks to the shores of Lake Erie. Some scattered bands had even pushed farther westward along the Ohio River and settled there.
    Cover page: The Haldimand Agreement: A Continuing CovenantCreative Commons 'BY-NC' version 4.0 license
    • Thesis
    • Peer Reviewed
    UC Berkeley Electronic Theses and Dissertations (2021)

    Although spittlebugs were first confirmed as vectors of Xylella fastidiosa in the 1950s, their role in epidemics of Pierce’s disease of grapevine in the California North Coast remains unknown. The goal of this dissertation was to assess the biology and ecology of spittlebug vectors, Philaenus spumarius and Aphrophora nr. permutata, in California North Coast vineyards in relation to Pierce’s disease and to characterize differences in X. fastidiosa transmission following acquisition by spittlebug and sharpshooter leafhopper vectors.In chapter 1, I provide a brief background on the plant pathogenic bacterium, X. fastidiosa, its associated diseases, and its relationship with plant hosts and insect vectors. I also contextualize and summarize the subsequent chapters of my dissertation. Chapter 2 explores the seasonal abundance and infectivity of P. spumarius in California North Coast vineyards. Analysis of sweep and trap data revealed significant effects of survey month, vineyard site, and year on adult abundance in sweep and trap surveys. Analysis of X. fastidiosa natural infectivity in groups of field-collected spittlebug adults showed significant difference in transmission rates among months. I propose hypotheses on how to contextualize P. spumarius infectivity within the established framework of Pierce’s disease winter recovery. In chapter 3, I present results from a four-year field study analyzing the effects of site characteristics and host plant community on the abundance and development of A. nr. permutata nymphs. Woodland and riparian sites hosted larger nymphal populations than sites surrounded by vineyards. Among plant cover taxa surveyed in 2020, A. nr. permutata nymph abundance was positively associated with Helminthotheca echoides, Vicia sativa, and Daucus carota cover and negatively associated with Taraxacum officinale cover. Analysis of the development surveys found a significant effect of site, year, and plant taxa on first detection of nymphs as well as a significant effect of site and year on the estimated development time between 1st and 5th instars. In chapter 4, I assess differences in X. fastidiosa transmission efficiency over time between P. spumarius and the blue green sharpshooter, Graphocephala atropunctata. There was a significant effect of days post-acquisition on the proportion of plants infected by P. spumarius but the effect of days post-acquisition on G. atropunctata transmission efficiency was not significant. I consider species specific feeding behaviors and mouthpart fluid dynamics to explain the observed transmission patterns.

      Cover page: Assessing Vectors of Xylella fastidiosa in California: From Ecology to Transmission Dynamics
      • Article
      Earlier Faculty Research (2008)

      The paper describes a methodology and its application to measure total, recurrent, and non-recurrent (incident related) delay on urban freeways. The methodology uses data from loop detectors and calculates the average and the probability distribution of delays. Application of the methodology to two real-life freeway corridors—one in Los Angeles and the other in the Bay Area—indicates that reliable measurement of congestion should also provide measures of uncertainty in congestion. In the two applications, incident-related delay is found to be between 13 to 30 percent of the total congestion delay during peak periods. The methodology also quantifies the congestion impacts on travel time and travel time variability.

        Cover page: MEASURING RECURRENT AND NON-RECURRENT TRAFFIC CONGESTION
        • Article
        Proceedings of the Vertebrate Pest Conference, Volume 9 (1980)
        Vacor (RH-787), a relatively new rodenticide, was evaluated for the control of Rattus rattus rufescens. The symptoms of paralysis in hind limbs were observed after feeding it to rodents. The susceptibility to this rodenticide in Rattus rattus increased with the increase in its concentration. Experimental observations revealed that RH-787 bait with 0.0125% concentration affects the reproductive biology of the rats. Bait with 0.025% Vacor proved sublethal and within 5 days 70% mortality was observed, while 100% mortality was observed when rats were fed with 0.05% Vacor
          Cover page: Studies on the toxicity of Vacor (RH-787) on the reproductive biology of Rattus rattus rufescens
          • Article
          • Peer Reviewed
          Berkeley Research Impact Initiative (BRII) (2009)
          Many insect-borne pathogens have complex life histories because they must colonize both hosts and vectors for successful dissemination. In addition, the transition from host to vector environments may require changes in gene expression before the pathogen's departure from the host. Xylella fastidiosa is a xylem-limited plant-pathogenic bacterium transmitted by leafhopper vectors that causes diseases in a number of economically important plants. We hypothesized that factors of host origin, such as plant structural polysaccharides, are important in regulating X. fastidiosa gene expression and mediating vector transmission of this pathogen. The addition of pectin and glucan to a simple defined medium resulted in dramatic changes in X. fastidiosa's phenotype and gene-expression profile. Cells grown in the presence of pectin became more adhesive than in other media tested. In addition, the presence of pectin and glucan in media resulted in significant changes in the expression of several genes previously identified as important for X. fastidiosa's pathogenicity in plants. Furthermore, vector transmission of X. fastidiosa was induced in the presence of both polysaccharides. Our data show that host structural polysaccharides mediate gene regulation in X. fastidiosa, which results in phenotypic changes required for vector transmission. A better understanding of how vector-borne pathogens transition from host to vector, and vice versa, may lead to previously undiscovered disease-control strategies.
            • Article
            Research Reports (1991)

            Presents a sketch of a system architecture for the control and management tasks of an intelligent vehicle/highway system (IVHS)

              Cover page: Sketch Of An Ivhs Systems Architecture
              • Article
              • Peer Reviewed
              Berkeley Research Impact Initiative (BRII) (2011)
              Using DNA sequence data from pathogens to infer transmission networks has traditionally been done in the context of epidemics and outbreaks. Sequence data could analogously be applied to cases of ubiquitous commensal bacteria; however, instead of inferring chains of transmission to track the spread of a pathogen, sequence data for bacteria circulating in an endemic equilibrium could be used to infer information about host contact networks. Here, we show—using simulated data—that multilocus DNA sequence data, based on multilocus sequence typing schemes (MLST), from isolates of commensal bacteria can be used to infer both local and global properties of the contact networks of the populations being sampled. Specifically, for MLST data simulated from small-world networks, the small world parameter controlling the degree of structure in the contact network can robustly be estimated. Moreover, we show that pairwise distances in the network—degrees of separation—correlate with genetic distances between isolates, so that how far apart two individuals in the network are can be inferred from MLST analysis of their commensal bacteria. This result has important consequences, and we show an example from epidemiology: how this result could be used to test for infectious origins of diseases of unknown etiology.
                • Article
                Proceedings of the Vertebrate Pest Conference, Volume 13 (1988)
                The starling is one of the major pest birds in France. During the winter, starlings coming from other parts of Europe gather in the Northwest of France and cause extensive damage in the corn silage distributed to the cattle, by eating and spoiling the grains. As it is impossible to protect the cattle food by physical means in most of the situations, the persons in charge of resolving the problem have chosen to turn towards chemical roost treatments. Between 1980 and 1988, nearly 40 treatments have been carried out on 25 different roosts. The chemical used is CPT (chloro-para-toluidin) applied at the rate of 100 kg per hectare. Water is added to the formulated product and a volume of 1000 liters per hectare of the treatment mixture is applied with a fixed-wing aircraft. Results usually ranged from 30% to 80% of the birds killed. No phytotoxic problems have been reported on the roost sites, and only light wildlife adverse effects arc mentioned. Studies are going on with the following points: degradation of CPT in the soil, and reduction of the amount of CPT and/or water without drop of effectiveness.
                  Cover page: Aerial treatments against starling roosts in France with chloro-para-toluidin (CPT): Results of eight years of experiments
                  • Article
                  • Peer Reviewed
                  UC Irvine Previously Published Works (1973)
                    Cover page: Importance of the nucleolus in the initiation of DNA synthesis in mammalian cells. Studies with an ultraviolet microbeam and low concentrations of actinomycin D.
                    • Article
                    • Peer Reviewed
                    UC San Diego Previously Published Works (2010)
                    The University of California, San Diego (UCSD) three-dimensional (3-D) time-dependent tomography program has been used successfully for a decade to reconstruct and forecast coronal mass ejections from interplanetary scintillation observations. More recently, we have extended this tomography technique to use remote-sensing data from the Solar Mass Ejection Imager (SMEI) on board the Coriolis spacecraft; from the Ootacamund (Ooty) radio telescope in India; and from the European Incoherent SCATter (EISCAT) radar telescopes in northern Scandinavia. Finally, we intend these analyses to be used with observations from the Murchison Widefield Array (MWA), or the LOw Frequency ARray (LOFAR) now being developed respectively in Australia and Europe. In this article we demonstrate how in-situ velocity measurements from the Advanced Composition Explorer (ACE) space-borne instrumentation can be used in addition to remote-sensing data to constrain the time-dependent tomographic solution. Supplementing the remote-sensing observations with in-situ measurements provides additional information to construct an iterated solar-wind parameter that is propagated outward from near the solar surface past the measurement location, and throughout the volume. While the largest changes within the volume are close to the radial directions that incorporate the in-situ measurements, their inclusion significantly reduces the uncertainty in extending these measurements to global 3-D reconstructions that are distant in time and space from the spacecraft. At Earth, this can provide a finely-tuned real-time measurement up to the latest time for which in-situ measurements are available, and enables more-accurate forecasting beyond this than remote-sensing observations alone allow.
                      Cover page: Inclusion of In-Situ Velocity Measurements into the UCSD Time-Dependent Tomography to Constrain and Better-Forecast Remote-Sensing Observations
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