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Open Access Publications from the University of California

Scholarly Works (582 results)

  • Article
Other Recent Work (2021)
    • Article
    Other Recent Work (2023)
      Cover page: The Economic Cost of SOGIESC-Based Exclusion in the Republic of Serbia
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      • Peer Reviewed
      UC Davis Previously Published Works (2011)
      The orbital properties of infalling satellite haloes set the initial conditions which control the subsequent evolution of subhaloes and the galaxies that they host, with implications for mass stripping, star formation quenching and merging. Using a high-resolution cosmological N-body simulation, we examine the orbital parameters of satellite haloes as they merge with larger host haloes, focusing primarily on orbital circularity and pericentre. We explore in detail how these orbital parameters depend on mass and redshift. Satellite orbits become more radial and plunge deeper into their host halo at higher host halo mass, but they do not significantly depend on satellite halo mass. Additionally, satellite orbits become more radial and plunge deeper into their host haloes at higher redshift. We also examine satellite velocities, finding that most satellites infall with less specific angular momentum than the host halo virial value, but that satellites are 'hotter' than the host virial velocity. We discuss the implications of these results to the processes of galaxy formation and evolution, and we provide fitting formulae to the mass and redshift dependence of satellite orbital circularity and pericentre. © 2010 The Author Monthly Notices of the Royal Astronomical Society © 2010 RAS.
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        Other Recent Work (2015)
        Transgender people face an uncertain legal climate, and efforts to include gender identity in policies have been met with both successes and failures. These policies are often developed in the legislative process, which directly involve public opinion. To date, there is only one study analyzing American public attitudes toward transgender people. This research gap makes it unclear whether people in general understand what transgender means and whether public support for transgender rights depends on understanding and knowing transgender people. Since the population of transgender people is estimated to be smaller than that of lesbian, gay, and bisexual people, examining whether and how having a friend or family member who is lesbian or gay relates to transgender rights is important to understand political coalitions and attitude change. This study examines public attitudes about transgender rights in the USA. It finds that as respondents report being more informed about transgender people they tend to have more supportive attitudes. Interpersonal contact with someone who is lesbian or gay also leads to a secondary transfer of positive attitudes. About half of the secondary transfer effect operates through a mechanism of attitude generalization: contact positively affects the opinions people have on gay rights that then broaden to affect attitudes on transgender rights. Demographic characteristics also indicate that predictors of transgender attitudes are similar to previous studies regarding attitudes toward lesbians, gay men, and bisexuals. Further survey efforts need to consider inquiring about transgender rights and attitudes, as this remains a research gap in need of scholarly understanding.
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          • Peer Reviewed
          International Journal of Comparative Psychology, Volume 24, Issue 4 (2011)
          This paper reviews some of the literature on Pavlovian and instrumental conditioning as they relate to“cognitive” factors in behavior. Studies of Pavlovian learning have centered around the notion that a representation of the unconditioned stimulus plays a critical role in performance. However, much work will need to go into characterizing the nature of the representations that mediate learning. In particular, current research illustrates that “images” and “expectancies” of reward may differ in fundamental ways, and also that learning about temporal, motivational, and sensory properties of reward might involve different systems. The study of instrumental learning also poses challenges for addressing the question of what representations, i.e., associative structures, underlie such learning.Current work reveals a host of associative structures that may participate in learning and performance though how these different structures participate in a unified approach is currently unknown. The associative approach can be contrasted with inferential reasoning approaches to instrumental action, and there are two key findings that seem outside the scope of a reasoning approach. Nevertheless, future work will be required to determine just how far purely associative models will be able to go in order to account for complex behavior.
            Cover page: At the Interface of Learning and Cognition:An Associative Learning PerspectiveCreative Commons 'BY' version 4.0 license
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            • Peer Reviewed
            Other Recent Work (2014)
            Lesbian, gay, and bisexual (LGB) people reside in practically every geographic region in the United States, with substantial variationregarding what proportion of that region is populated with LGB people. Given this variation, I analyze whether denser LGB congressional districts have an effect on individuals’ views on relationship recognition rightsfor same-sex couples. LGB population density could have two potentialeffects: normalizing contact or contextual threat. I find that as the LGB population density in legislative districts increases, so too does theprobability of individuals supporting relationship rights for same-sexcouples. As the results indicate, context does not increase threat.
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              • Peer Reviewed
              Scripps Institution of Oceanography Technical Report (2010)

              Methane seeps host a diversity of metazoans that co-occur with chemoautotrophic Bacteria and Archaea, providing a model system to study trophic microbe-metazoan interactions. The goal of this dissertation is to characterize and quantify the types of microbial production consumed by methane-seep fauna. Through combined laboratory and field studies from four methane seep locations (11 New Zealand sites; Eel River; Hydrate Ridge; and Costa Rica’s Mound 12), I found that aerobic methane-oxidizing bacteria and the syntrophic partnership which mediates the anaerobic oxidation of methane are consumed within metazoan food webs. In New Zealand, two communities were largely fueled by methane: (1) a sponge which provided a habitat and trophic conduit of methane-derived production to a diversity of fauna and (2) ampharetid polychaete beds. These ampharetid beds formed a distinct community which was fueled by aerobic methane-oxidizing bacteria, as shown through stable isotopic and fatty-acid analysis coupled to a mass-specific mixing model. The Dorvilleidae, a polychaete family which excels at inhabiting areas with high microbial production, provided a ideal taxa to study metazoan trophic linkages to Archaea. In the laboratory, I raised Ophryotrocha labronica, a dorvilleid, from egg to reproduction on monocultures of archaeal, bacterial and eukaryotic food sources. This demonstrated that all domains of life can support viable metazoan populations. In contrast to current biomarker paradigms, this species exhibited isotopic enrichment (not composition) which was foodsource specific whereas fatty-acid signature was largely not; a finding that explained many of the patterns observed in the field studies. Although archaeal biomarkers were not transferred from diet to consumer, sulfate-reducing bacteria, a member of the assemblage responsible for the anaerobic oxidation of methane, provided a mechanism that identified archaeal aggregates as a food source for dorvilleids in both authigenic-carbonate and soft-sediment habitats. As a final example of microbial-metazoan interactions, during the formal description of a novel species of Yeti crab, I identified how this crab farms chemosynthetic-epibiotic bacteria by waving its bacteria-covered setae in methane-seep fluid. This research demonstrates the ubiquity of strong trophic links between chemoautotrophic microbes and heterotrophic metazoans while highlighting how these interactions vary among site and habitat at seeps.

                Cover page: Microbe-Metazoan interactions at Pacific Ocean methane seeps
                • Article
                UCR Honors Capstones 2021-2022 (2022)
                  Cover page: WHAT WE HAVE LEARNED FROM COVID-19, A LITERATURE ANALYSIS
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                  • Peer Reviewed
                  Other Recent Work (2015)
                  Recent polls report majorities of the public supporting marriage recognition for same-sex couples. These reports are not uniform, with some polling organizations still reporting less than a majority in favor. I examine variation in these results using meta-analysis to examine variation among organizations (norg=21) and question wordings (nqw=36) . I also examine direct effects that explain variation based on question framing from 1996 to 2014 (npoll=138) . The results show that after accounting for this variation, a majority of the public supports same-sex marriage in 2014, and any deviations from that estimate can be explained by question framing and organizational “house” effects. The results indicate that questions that focus on the issue of “same-sex marriage” garner less support than questions on legal recognition of marriages for same-sex couples; this finding suggests that framing accounts for why some polls do not report majorities in favor.
                    • Article
                    Other Recent Work (2023)
                      Cover page: The Economic Cost of SOGIESC-Based Exclusion in the Republic of North Macedonia
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