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Open Access Publications from the University of California

Scholarly Works (12 results)

  • Thesis
  • Peer Reviewed
UC San Diego Electronic Theses and Dissertations (2022)

In recent years, the United States has seen an increased interest in Dual Language Education (DLE) Programs. These programs prepare students to compete in a global economy by providing an opportunity to develop high levels of bilingualism, biliteracy, and socio-cultural competence. Despite abundant research on DLE programs (Howard et al., 2018), there are not enough studies on the role of the school principal as an educational leader in these additive enrichment language programs. As the primary advocates for these programs, school principals are instrumental in providing support and guidance to the learning communities they lead, thus ensuring high quality and equity through their leadership and commitment to the programs’ vision and mission. Consequently, this qualitative case study employed Transformational Leadership Theory (Bass, 1985, 2006) and the Principles of Courageous Leadership (Blankstein & Noguera, 2016) as a dual lens framework to examine the role and characteristics of two school principals at distinct DLE programs in Southern California. Methodology included surveys and interviews with a sample size of two principals, six teachers, and six parents in DLE programs. Findings in this study revealed how through liderazgo and authentic cariño the school principals created equitable schooling experiences for students and teachers. The findings in the case study yielded four themes 1) the principals’ strong belief in DLE, 2) advocacy for program and professional development, 3) pedagogical knowledge and sustainability of DLE, and 4) building cross-cultural relationships and appreciation of cutures. Implications of this study may add to the scholarly literature and inform the field of the unique characteristics of school principals in DLE.Given the constraints of COVID-19, data obtained from the study was carefully examined due to the impact on participants’ experience and potential biases in the educational setting.

    Cover page: Examining the Role of Critically Conscious Leadership in Dual Language Education Programs: A Case of Two School Principals
    • Thesis
    • Peer Reviewed
    UC San Diego Electronic Theses and Dissertations (2011)
    Growing numbers of English Learners (ELs) in public education are placed in a variety of second language programs across the nation. Policymakers, educators, and parents are indecisive on which programs are most beneficial for the linguistic and cultural needs of ELs. Empirical studies on two-way bilingual immersion (TWBI) programs seem to provide promising data for ELs receiving content instruction in their primary language while acquiring second language acquisition skills in classrooms where students are integrated with native English speakers. The goals of TWBI programs are for all students to become bilingual, biliterate, and bicultural. This study examined the instructional strategies teachers used to develop biliteracy and cross-cultural competence in TWBI. A single case study approach allowed the researcher to gain insights about the implementation of strategies in two TWBI programs in Southern California. The methods included multiple measures to collect and analyze the data through photo-elicitation journals, appreciative inquiry interviews, lesson observations, teacher reflections, and questionnaires. The sample population for this case study included nine bilingual teachers in TWBI programs with 90/ 10 model designs in grades first through sixth. First, the research synthesized how the teachers gained their knowledge-base and professional support to implement their strategies. Second, the findings discussed how the framework for the Guiding Principles for Dual Language Education assisted teachers in the implementation of their instructional strategies. Third, the data analysis described the successes and challenges in the teachers' instructional strategies to develop biliteracy and cross- cultural competence with ELs and English Proficient students in their classrooms. Lastly, the study discussed how the teachers gained new insights about their practices based on their successes and challenges in their strategies. Results of the study demonstrated that teachers were very experienced and knowledgeable in TWBI practices and supported each other through planning and lesson development. Teachers implemented strategies aligned to the four main guiding principles of instruction : research-based practices, instructional strategies, student-centered instruction, and multicultural/ multilingual learning environments. Convergence of multiple measures indicated that teachers experienced successes and challenges in their instructional strategies for biliteracy and cross-cultural competence, but established new perspectives and innovations to advance their practice
      Cover page: Successes and challenges of instructional strategies in two-way bilingual immersion
      • Thesis
      • Peer Reviewed
      UC San Diego Electronic Theses and Dissertations (2024)

      For Latina school administrators, the movement through the principal pipeline is not easy, as many encounter discrimination and biases rooted in their gender, ethnicity and other intersecting identities. Schools should leverage Latina administrators' cultural knowledge, perspectives, and experience to improve student educational outcomes. A Latina administrator brings these prior experiences to the work and can better understand and support the needs of the growing Latino/a population (Crawford & Fuller, 2017; Elizondo, 2005; Magdaleno, 2006; Méndez-Morse, 2004; Méndez-Morse, & Byrne-Jiménez, 2016; Murakami, Hernandez, 2016; Rodríguez, Martínez, & Falle, 2015). The dissertation highlights four Latina administrators' personal and professional journeys as they navigated the principal pipeline through interviews. Through participant and mentor interviews, the researcher sought to uncover the challenges, triumphs, and support systems the Latinas faced during their trajectory. The dissertation highlights participant stories with the objective of understanding how they overcame challenges and barriers with mentorship support. Latina representation is crucial, yet Latinas are scarce in leadership roles (Bitterman et al., 2013). Importance must be placed on actively developing a diverse group of Latina administrators, to ensure school leaders are better equipped to understand and address the academic challenges and disparities faced by Latino/a students due to their shared cultural backgrounds and experiences. The framework for this dissertation, Latina/o Critical Race Theory, or LatCrit, (Solorzano & Bernal, 2001), encompasses a range of social constructs such as racism, classism, sexism, and other forms of oppression that exist within the lived experiences of Latino/a administrators. As LatCrit is explored, these four Latinas' experiences showcase how social constructs intersect with their individual journeys. The findings revealed that while the four Latinas navigated their pathways to the principalship, they found empowerment through mentorships. They drew strengths from their identity and their mentors, took on a Sí se Puede mindset and pursued their Calling, or Vocación, and became principals.

        Cover page: Sí se pudo y con tacones: Understanding the Racialized Barriers and Challenges that Empower the Goals of Latina School Administrators
        • Article
        • Peer Reviewed
        UC San Francisco Previously Published Works (2012)

        Background

        Anatomic diversity among cerebellar arteriovenous malformations (AVMs) calls for a classification that is intuitive and surgically informative. Selection tools like the Spetzler-Martin grading system are designed to work best with cerebral AVMs but have shortcomings with cerebellar AVMs.

        Objective

        To define subtypes of cerebellar AVMs that clarify anatomy and surgical management, to determine results according to subtypes, and to compare predictive accuracies of the Spetzler-Martin and supplementary systems.

        Methods

        From a consecutive surgical series of 500 patients, 60 had cerebellar AVMs, 39 had brainstem AVMs and were excluded, and 401 had cerebral AVMs.

        Results

        Cerebellar AVM subtypes were as follows: 18 vermian, 13 suboccipital, 12 tentorial, 12 petrosal, and 5 tonsillar. Patients with tonsillar and tentorial AVMs fared best. Cerebellar AVMs presented with hemorrhage more than cerebral AVMs (P < .001). Cerebellar AVMs were more likely to drain deep (P = .04) and less likely to be eloquent (P < .001). The predictive accuracy of the supplementary grade was better than that of the Spetzler-Martin grade with cerebellar AVMs (areas under the receiver-operating characteristic curve, 0.74 and 0.59, respectively). The predictive accuracy of the supplementary system was consistent for cerebral and cerebellar AVMs, whereas that of the Spetzler-Martin system was greater with cerebral AVMs.

        Conclusion

        Patients with cerebellar AVMs present with hemorrhage more often than patients with cerebral AVMs, justifying an aggressive treatment posture. The supplementary system is better than the Spetzler-Martin system at predicting outcomes after cerebellar AVM resection. Key components of the Spetzler-Martin system such as venous drainage and eloquence are distorted by cerebellar anatomy in ways that components of the supplementary system are not.
          Cover page: Cerebellar Arteriovenous Malformations: Anatomic Subtypes, Surgical Results, and Increased Predictive Accuracy of the Supplementary Grading System
          • Article
          • Peer Reviewed
          UC Santa Cruz Previously Published Works (2016)
          UNLABELLED: The presence of the Lon protease in all three domains of life hints at its biological importance. The prokaryotic Lon protease is responsible not only for degrading abnormal proteins but also for carrying out the proteolytic regulation of specific protein targets. Posttranslational regulation by Lon is known to affect a variety of physiological traits in many bacteria, including biofilm formation, motility, and virulence. Here, we identify the regulatory roles of LonA in the human pathogen Vibrio cholerae. We determined that the absence of LonA adversely affects biofilm formation, increases swimming motility, and influences intracellular levels of cyclic diguanylate. Whole-genome expression analysis revealed that the message abundance of genes involved in biofilm formation was decreased but that the message abundances of those involved in virulence and the type VI secretion system were increased in a lonA mutant compared to the wild type. We further demonstrated that a lonA mutant displays an increase in type VI secretion system activity and is markedly defective in colonization of the infant mouse. These findings suggest that LonA plays a critical role in the environmental survival and virulence of V. cholerae. IMPORTANCE: Bacteria utilize intracellular proteases to degrade damaged proteins and adapt to changing environments. The Lon protease has been shown to be important for environmental adaptation and plays a crucial role in regulating the motility, biofilm formation, and virulence of numerous plant and animal pathogens. We find that LonA of the human pathogen V. cholerae is in line with this trend, as the deletion of LonA leads to hypermotility and defects in both biofilm formation and colonization of the infant mouse. In addition, we show that LonA regulates levels of cyclic diguanylate and the type VI secretion system. Our observations add to the known regulatory repertoire of the Lon protease and the current understanding of V. cholerae physiology.
            Cover page: The LonA Protease Regulates Biofilm Formation, Motility, Virulence, and the Type VI Secretion System in Vibrio cholerae.
            • Article
            • Peer Reviewed
            UC San Francisco Previously Published Works (2015)
            The understanding of the pathophysiology of brain arteriovenous malformations and arteriovenous fistulas has improved thanks to animal models. A rat model creating an artificial fistula between the common carotid artery (CCA) and the external jugular vein (EJV) has been widely described and proved technically feasible. This construct provokes a consistent cerebral venous hypertension (CVH), and therefore has helped studying the contribution of venous hypertension to formation, clinical symptoms, and prognosis of brain AVMs and dural AVFs. Equivalent mice models have been only scarcely described and have shown trouble with stenosis of the fistula. An established murine model would allow the study of not only pathophysiology but also potential genetic therapies for these cerebrovascular diseases. We present a model of arteriovenous fistula that produces a durable intracranial venous hypertension in the mouse. Microsurgical anastomosis of the murine CCA and EJV can be difficult due to diminutive anatomy and frequently result in a non-patent fistula. In this step-by-step protocol we address all the important challenges encountered during this procedure. Avoiding excessive retraction of the vein during the exposure, using 11-0 sutures instead of 10-0, and making a carefully planned end-to-side anastomosis are some of the critical steps. Although this method requires advanced microsurgical skills and a longer learning curve that the equivalent in the rat, it can be consistently developed. This novel model has been designed to integrate transgenic mouse techniques with a previously well-established experimental system that has proved useful to study brain AVMs and dural AVFs. By opening the possibility of using transgenic mice, a broader spectrum of valid models can be achieved and genetic treatments can also be tested. The experimental construct could also be further adapted to the study of other cerebrovascular diseases related with venous hypertension such as migraine, transient global amnesia, transient monocular blindness, etc.
              Cover page: Adult mouse venous hypertension model: common carotid artery to external jugular vein anastomosis.
              • Article
              • Peer Reviewed
              UC San Francisco Previously Published Works (2013)
              BACKGROUND: Influenza-like illnesses (ILI) are estimated to cause millions of deaths annually. Despite this disease burden, the etiologic causes of ILI are poorly described for many geographical regions. METHODS: Beginning in April 2010, we conducted an observational cohort study at five hospitals in Mexico City, enrolling subjects who met the criteria for ILI. Evaluations were conducted at enrollment and on day 28, with the collection of clinical data and a nasopharyngeal swab (or nasal aspirate in children). Swabs were tested by multiplex PCR for 15 viral pathogens and real-time PCR for influenza. RESULTS: During the first year, 1065 subjects were enrolled in this study, 55% of whom were hospitalized; 24% of all subjects were children. One or more pathogens were detected by PCR in 64% of subjects, most commonly rhinovirus (25% of all isolates) and influenza (24% of isolates). Six percent of subjects died, and of those, 54% had no pathogen identified. Rhinovirus was the most common pathogen among those who died, although it did not have the highest case fatality rate. CONCLUSIONS: Multiple respiratory viruses beyond influenza are associated with significant morbidity and mortality among adults and children in Mexico City. Detection of these agents could be useful for the adjustment of antibiotic treatment in severe cases.
                Cover page: Clinical characteristics and outcomes of influenza and other influenza-like illnesses in Mexico City.
                • Article
                • Peer Reviewed
                UC San Francisco Previously Published Works (2021)
                G protein-coupled receptors (GPCRs) are a group of seven-transmembrane receptor proteins that have proven to be successful drug targets. Antibodies are becoming an increasingly promising modality to target these receptors due to their unique properties, such as exquisite specificity, long half-life, and fewer side effects, and their improved pharmacokinetic and pharmacodynamic profiles compared to peptides and small molecules, which results from their more favorable biodistribution. To date, there are only two US Food and Drug Administration-approved GPCR antibody drugs, namely erenumab and mogamulizumab, and this highlights the challenges encountered in identifying functional antibodies against GPCRs. Utilizing Twists precision DNA writing technologies, we have created a GPCR-focused phage display library with 1 × 1010 diversity. Specifically, we mined endogenous GPCR binding ligand and peptide sequences and incorporated these binding motifs into the heavy chain complementarity-determining region 3 in a synthetic antibody library. Glucagon-like peptide-1 receptor (GLP-1 R) is a class B GPCR that acts as the receptor for the incretin GLP-1, which is released to regulate insulin levels in response to food intake. GLP-1 R agonists have been widely used to increase insulin secretion to lower blood glucose levels for the treatment of type 1 and type 2 diabetes, whereas GLP-1 R antagonists have applications in the treatment of severe hypoglycemia associated with bariatric surgery and hyperinsulinomic hypoglycemia. Here we present the discovery and creation of both antagonistic and agonistic GLP-1 R antibodies by panning this GPCR-focused phage display library on a GLP-1 R-overexpressing Chinese hamster ovary cell line and demonstrate their in vitro and in vivo functional activity.
                  Cover page: Functional GLP-1R antibodies identified from a synthetic GPCR-focused library demonstrate potent blood glucose control.
                  • Article
                  • Peer Reviewed
                  UC San Diego Previously Published Works (2018)
                  Alzheimer's disease is a devastating neurodegenerative disease eventually leading to dementia. An effective treatment does not yet exist. Here we show that oral application of the compound anle138b restores hippocampal synaptic and transcriptional plasticity as well as spatial memory in a mouse model for Alzheimer's disease, when given orally before or after the onset of pathology. At the mechanistic level, we provide evidence that anle138b blocks the activity of conducting Aβ pores without changing the membrane embedded Aβ-oligomer structure. In conclusion, our data suggest that anle138b is a novel and promising compound to treat AD-related pathology that should be investigated further.
                    Cover page: The diphenylpyrazole compound anle138b blocks Aβ channels and rescues disease phenotypes in a mouse model for amyloid pathology
                    • Article
                    • Peer Reviewed
                    UC San Diego Previously Published Works (2019)
                    The 17th International HLA and Immunogenetics Workshop (IHIW) organizers conducted a Pilot Study (PS) in which 13 laboratories (15 groups) participated to assess the performance of the various sequencing library preparation protocols, NGS platforms and software in use prior to the workshop. The organizers sent 50 cell lines to each of the 15 groups, scored the 15 independently generated sets of NGS HLA genotyping data, and generated "consensus" HLA genotypes for each of the 50 cell lines. Proficiency Testing (PT) was subsequently organized using four sets of 24 cell lines, selected from 48 of 50 PS cell lines, to validate the quality of NGS HLA typing data from the 34 participating IHIW laboratories. Completion of the PT program with a minimum score of 95% concordance at the HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 loci satisfied the requirements to submit NGS HLA typing data for the 17th IHIW projects. Together, these PS and PT efforts constituted the 17th IHIW Quality Control project. Overall PT concordance rates for HLA-A, HLA-B, HLA-C, HLA-DPA1, HLA-DPB1, HLA-DQA1, HLA-DQB1, HLA-DRB1, HLA-DRB3, HLA-DRB4 and HLA-DRB5 were 98.1%, 97.0% and 98.1%, 99.0%, 98.6%, 98.8%, 97.6%, 96.0%, 99.1%, 90.0% and 91.7%, respectively. Across all loci, the majority of the discordance was due to allele dropout. The high cost of NGS HLA genotyping per experiment likely prevented the retyping of initially failed HLA loci. Despite the high HLA genotype concordance rates of the software, there remains room for improvement in the assembly of more accurate consensus DNA sequences by NGS HLA genotyping software.
                      Cover page: Quality control project of NGS HLA genotyping for the 17th International HLA and Immunogenetics Workshop
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