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Open Access Publications from the University of California

Scholarly Works (25 results)

  • Article
  • Peer Reviewed
Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health, Volume 9, Issue 1 (2008)
    Cover page: Incidence of Ovarian Tumor on 1st-Trimester Pelvic Ultrasounds in the ED
    • Article
    • Peer Reviewed
    UCLA Previously Published Works (2018)
    This study identifies the solar origins of magnetic clouds that are observed at 1 AU and predicts the helical handedness of these clouds from the solar surface magnetic fields. We started with the magnetic clouds listed by the Magnetic Field Investigation (MFI) team supporting NASA's Wind spacecraft in what is known as the MFI table and worked backward in time to identify solar events that produced these clouds. Our methods utilize magnetograms from the Helioseismic and Magnetic Imager instrument on the Solar Dynamics Observatory spacecraft so that we could only analyze MFI entries after the beginning of 2011. This start date and the end date of the MFI table gave us 37 cases to study. Of these we were able to associate only eight surface events with clouds detected by Wind at 1 AU. We developed a simple algorithm for predicting the cloud helicity that gave the correct handedness in all eight cases. The algorithm is based on the conceptual model that an ejected flux tube has two magnetic origination points at the positions of the strongest radial magnetic field regions of opposite polarity near the places where the ejected arches end at the solar surface. We were unable to find events for the remaining 29 cases: lack of a halo or partial halo coronal mass ejection in an appropriate time window, lack of magnetic and/or filament activity in the proper part of the solar disk, or the event was too far from disk center. The occurrence of a flare was not a requirement for making the identification but in fact flares, often weak, did occur for seven of the eight cases.
      Cover page: Solar Sources of Interplanetary Magnetic Clouds Leading to Helicity Prediction
      • Article
      Technical Reports (2003)

      Embedded networked sensors promise to revolutionize the way we interact with our physical envi- ronment and require scalable, ad hoc deployable and energy-ecient node localization/positioning. This paper describes the motivation, design, implementation and experimental evaluation (on sharply resource-constrained devices) of a self-con�guring localization system using radio beacons. We identify beacon density as an important parameter in determining localization quality, which saturates at a transition density. We develop algorithms to improve localization quality by (i) automating placement of new beacons at low densities (HEAP) and (ii) rotating functionality among redundant beacons while increasing system lifetime at high densities (STROBE).

        Cover page: Self-configuring Localization Systems: Design and Experimental Evaluation
        • Article
        • Peer Reviewed
        Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health, Volume 9, Issue 3 (2008)

        Background: Health literacy is an important predictor of healthcare outcomes, but research on this topic has largely been absent from the emergency medicine literature.

        Objectives: We measured the prevalence of health literacy in parents or guardians of pediatric patients seen in the emergency department (ED).

        Methods: This was an observational study conducted in a Midwestern urban, university-based, tertiary, Level 1 trauma center ED with 33,000 visits/year. Using convenience sampling during a three-month period, English-speaking parents or guardians of pediatric patients (< 19 yrs.) were asked to complete the short version of the Test of Functional Health Literacy for Adults (s-TOFHLA). Parents/guardians were excluded if they had uncorrected visual impairment, required an interpreter, had altered mental status, or if the patients they accompanied were the subjects of a medical or trauma activation.

        Results: Of the 188 parents or guardians approached, six did not consent or withdrew, one was excluded, leaving 181 (96.3%) in the study. Of these, 19 (10.5%) had either "marginal" or "inadequate" health literacy, while 162 (89.5%, 95% CI: 84.1%, 93.6%) had "adequate" health literacy.

        Conclusions: A large majority (89.5%) of English-speaking parents or guardians of pediatric patients evaluated in the ED have adequate health literacy. This data may prompt ED professionals to adjust their communication styles in the evaluation of children. Future multi-center studies are needed to confirm the findings in this pilot study. [WestJEM.2008:9:130-134]

          Cover page: Health Literacy Among Parents of Pediatric Patients Seen in the Emergency Department
          • Article
          Journal of Citrus Pathology, Volume 1, Issue 1 (2014)

          In the Mekong Delta, Vietnam, Citrus Huanglongbing (HLB) was officially announced in 1994 and its causal organism was described by Bove and Garnier in 1995 to be Candidatus Liberibacter asiaticus. Throughout the years, intensive works have been carried out for HLB control under small scale orchards and the achievements are discussed, the model for effective control of HLB under small scale which could elongate the life cycle of citrus tree for better and longer harvesting. In addition, there were 130 rutaceae related accessions had been collected and screened for HLB tolerance; the results revealed that the serverity of HLB infection was less on Hanh/Tac/Quat (Citrus microcarpa) and Long Co co pummelo (Citrus maxima) than that on orange and mandarin. The wild Rutaceae species/clones such as Quyt Dang, Quyt rung, Cam rung, Buoi Rung, Buoi Dang, Buoi Bung, Mac Run, Mac Mat, Can Thang, Quach, Nguyet Que, Kim quit, Truc, Com Ruou, Dau dau ba la, Ca ri, Da tu bien and Gioi Lom were symptomless under transmission conditions and had a negative reaction by PCR tests. In a molecular study, 38 primers have been designed and used for screening of HLB tolerance capacity of 49 varieties/clones belonging to Rutaceae. The preliminary results shown that the tolerant varieties was grouped into Group D, which somehow matched with the tolerant group screened under screenhouse conditions.

            Cover page: Results on attempts in management of HLB under small scale in Vietnam and initiation in screening for HLB tolerant from varieties/clones belonging to RutaceaeCreative Commons 'BY' version 4.0 license
            • Article
            • Peer Reviewed
            UC Irvine Previously Published Works (2022)

            Purpose of review

            The COVID-19 pandemic has revealed the importance of considering social determinants of health, including factors such as structural racism. This review discusses some of the evidence that triangulates on this issue, including data from hate crime statistics, social media analysis, and survey-based research. It also examines the data needs for Asian Americans, Native Hawaiian, and Pacific Islander (NHPI) communities.

            Recent findings

            The available data provides evidence that the pandemic has contributed to an increase in anti-Asian sentiment and discriminatory incidents. Many reports have surfaced showing a surge in anti-Chinese discrimination, which has "spilled over" into other Asian communities. Research is beginning to emerge to show that such discrimination may also impact health issues such as psychological distress. Given prior research, we would expect many more studies to emerge in the future. Also, the pandemic has illustrated the major gaps in data available to disentangle the health and social concerns facing Asian Americans and NHPI communities. Significant issues include the lack of systematic reporting of data for these communities both across states, and even among agencies within a state; erroneous aggregation of Asians with NHPIs; and censoring of data. These gaps and issues contribute to bias that obscures objective data and amplifies health inequalities.

            Summary

            The COVID-19 pandemic has had a negative impact on the well-being of Asian American and NHPI communities. It is critical to provide disaggregated data, not only so that we can have accurate reporting, but also to ensure data and health equity.
              Cover page: Considerations of Racism and Data Equity Among Asian Americans, Native Hawaiians, And Pacific Islanders in the Context of COVID-19
              • Article
              • Peer Reviewed
              UCLA Previously Published Works (2005)

              Aims To describe the drug use practices among female sex workers (FSWs) in Hanoi and to identify factors associated with their drug injecting. Design, setting and participants A two-stage cluster survey of 400 FSWs was conducted from June to September, 2002. Participating FSWs were both establishment- (160) and street-based (240), who were practising in seven urban and one suburban districts of Hanoi. Measurements Subjects were interviewed face to face using a structured questionnaire. Findings Among the middle-class FSWs, 27% used drugs, of whom 79% injected. Among low-class FSWs, 46% used drugs and 85% injected. Among drug-using FSWs, 86% had started using drugs within the past 6 years. Among drug-injecting FSWs, 81% had started injecting within the past 4 years. Cleaning of injecting equipment was not common among those who shared. Having drug-injecting 'love mates', drug-using clients, longer residence in Hanoi, more clients and not currently cohabiting were found to be independently associated with drug injecting among FSWs. Conclusions The high prevalence of injecting drug use among FSWs makes them susceptible to HIV infection, and is a threat to their clients. There is a strong relationship between drug-using FSWs and male drug-using clients and non-client partners. Intervention to prevent drug use initiation among non-drug-using FSWs and harm reduction among drug-using FSWs are urgently needed.

                Cover page: Drug use among female sex workers in Hanoi, Vietnam
                • Article
                • Peer Reviewed
                UCLA Previously Published Works (2023)

                Objectives

                We describe the perceptions and experiences of anti-Asian racism and violence and depression severity prior to and during the COVID-19 pandemic among a sample of Asian American (AA) adolescents and young adults.

                Methods

                We used data from the Young Asian American Health Survey (YAAHS), an online-recruited sample of AA adolescents (ages 13-17) and young adults (ages 18-29 years) conducted during May 2021 to March 2022. We presented descriptive statistics examining the univariate distribution and bivariate relationships of depression severity, sociodemographic characteristics, and experiences and perceptions of anti-Asian violence.

                Results

                Our sample (n = 176) comprised AA adolescents and young adults from 17 Asian ethnicities. A quarter said that the frequency and/or severity of their personal experiences of anti-Asian harassment had increased since the pandemic started. 76% indicated feeling less safe now than before the pandemic. Two-thirds reported that their depressive symptoms have increased since the pandemic started. Participants who reported feeling less safe now than before the pandemic were more likely to report increased personal experiences with anti-Asian harassment and increased depression severity since the pandemic started than those who reported feeling as safe or safer before the pandemic (p < 0.01 for both).

                Discussion

                Findings illustrate AA adolescent and young adults are experiencing multiple health and social crises stemming from increased anti-Asian racism during the COVID-19 pandemic. We urge policymakers to strengthen data systems that connect racial discrimination and mental health and to institute prevention measures and anti-racist mental health services that are age- and culturally-appropriate for AA adolescent and young adults.
                  Cover page: The mental health of Asian American adolescents and young adults amid the rise of anti-Asian racism
                  • Article
                  • Peer Reviewed
                  UC San Francisco Previously Published Works (2016)

                  Background

                  Disulfide-rich peptides (DRPs) are found throughout nature. They are suitable scaffolds for drug development due to their small cores, whose disulfide bonds impart extraordinary chemical and biological stability. A challenge in developing a DRP therapeutic is to engineer binding to a specific target. This challenge can be overcome by (i) sampling the large sequence space of a given scaffold through a phage display library and by (ii) panning multiple libraries encoding structurally distinct scaffolds. Here, we implement a protocol for defining these diverse scaffolds, based on clustering structurally defined DRPs according to their conformational similarity.

                  Results

                  We developed and applied a hierarchical clustering protocol based on DRP structural similarity, followed by two post-processing steps, to classify 806 unique DRP structures into 81 clusters. The 20 most populated clusters comprised 85% of all DRPs. Representative scaffolds were selected from each of these clusters; the representatives were structurally distinct from one another, but similar to other DRPs in their respective clusters. To demonstrate the utility of the clusters, phage libraries were constructed for three of the representative scaffolds and panned against interleukin-23. One library produced a peptide that bound to this target with an IC50 of 3.3 μM.

                  Conclusions

                  Most DRP clusters contained members that were diverse in sequence, host organism, and interacting proteins, indicating that cluster members were functionally diverse despite having similar structure. Only 20 peptide scaffolds accounted for most of the natural DRP structural diversity, providing suitable starting points for seeding phage display experiments. Through selection of the scaffold surface to vary in phage display, libraries can be designed that present sequence diversity in architecturally distinct, biologically relevant combinations of secondary structures. We supported this hypothesis with a proof-of-concept experiment in which three phage libraries were constructed and panned against the IL-23 target, resulting in a single-digit μM hit and suggesting that a collection of libraries based on the full set of 20 scaffolds increases the potential to identify efficiently peptide binders to a protein target in a drug discovery program.
                    Cover page: Clustering of disulfide-rich peptides provides scaffolds for hit discovery by phage display: application to interleukin-23
                    • Article
                    • Peer Reviewed
                    UC San Diego Previously Published Works (2017)

                    Background

                    The objective of this study was to determine whether hatha yoga is an efficacious adjunctive intervention for individuals with continued depressive symptoms despite antidepressant treatment.

                    Method

                    We conducted a randomized controlled trial of weekly yoga classes (n = 63) v. health education classes (Healthy Living Workshop; HLW; n = 59) in individuals with elevated depression symptoms and antidepressant medication use. HLW served as an attention-control group. The intervention period was 10 weeks, with follow-up assessments 3 and 6 months afterwards. The primary outcome was depression symptom severity assessed by blind rater at 10 weeks. Secondary outcomes included depression symptoms over the entire intervention and follow-up periods, social and role functioning, general health perceptions, pain, and physical functioning.

                    Results

                    At 10 weeks, we did not find a statistically significant difference between groups in depression symptoms (b = -0.82, s.e. = 0.88, p = 0.36). However, over the entire intervention and follow-up period, when controlling for baseline, yoga participants showed lower levels of depression than HLW participants (b = -1.38, s.e. = 0.57, p = 0.02). At 6-month follow-up, 51% of yoga participants demonstrated a response (⩾50% reduction in depression symptoms) compared with 31% of HLW participants (odds ratio = 2.31; p = 0.04). Yoga participants showed significantly better social and role functioning and general health perceptions over time.

                    Conclusions

                    Although we did not see a difference in depression symptoms at the end of the intervention period, yoga participants showed fewer depression symptoms over the entire follow-up period. Benefits of yoga may accumulate over time.
                      Cover page: Adjunctive yoga v. health education for persistent major depression: a randomized controlled trial
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