UC LEADS Alumni

The goal of the University of California's Leadership Excellence through Advanced Degrees (UC LEADS) program is to educate California's future leaders by preparing promising students for advanced education in science, technology, mathematics and engineering (STEM). The program is designed to identify upper-division undergraduate students with the potential to succeed in these disciplines, but who have experienced situations or conditions that have adversely affected their advancement in their fields of study.

Once chosen as UC LEADS scholar, students embark upon a two-year program of scientific research and graduate school preparation guided by individual faculty mentors.

Scholars get excellent opportunities to explore their disciplines, experience research environments and improve their opportunities for future study in their chosen fields. Each scholar gains valuable educational experience, the university gets a better prepared and more diverse graduate applicant pool, and the state, nation and world get well-educated future leaders.

2014-2016 Cohort

Hawi Gemeda

     Major: Biological Sciences

     Home City: San Leandro, CA

     Contact: hgemeda@ucmerced.edu

     Faculty Mentor: Professor Patricia LiWang

 

Hawi Gemeda is third year student in Biological Sciences, Molecular Biology emphasis.  She will be conducting research with professor Patricia Liwang in HIV inhibition and inflammation.  Growing up and observing people in her hometown, Ethopia, this research experience is very exciting to her since she saw people suffering from the HIV/AIDS in her neighborhood.  After getting her graduate degree, she plans to give service for the underserved population around the world.

Production of Recombinant Enterokinase Light Chain

Hawi B Gemeda, Mike Jian, Patricia LiWang, PhD, Molecular Cell Biology, University of California, Merced

Enterokinase, or enteropeptidase, is a serine protease which cleaves after the amino acid sequence DDDDK.  Recombinant Enterokinase (rEK) is commonly used to cleave off fusion tags during recombinant protein production. EK consists of a light chain and a heavy chain, with the light chain being the catalytic subunit. Many of the proteins of interest in our laboratory, such as 5P12-RANTES, are potent HIV inhibitors. These proteins are often recombinantly expressed with a fusion tag, requiring sequential enzymatic removal by EK cleavage.  It is not feasible to use commercial rEK for large scale production of these proteins due to the high cost.  A comprehensive search of current literature identified various methods to prepare rEK. We hypothesize that we can integrate and modify these methods to develop an optimized approach to produce rEK. The gene encoding the human EK catalytic light chain with a C122S mutation was subcloned into pET15b, pET28a, and pET32b expression vectors. The resulting plasmids were transformed into Escherichia Coli cells. rEK was overexpressed and then purified using an unfolding-refolding protocol. The product was analyzed for its specific protease activity. This homemade rEK is suggested as an economical alternative to the commercial enzyme. The development of this rEK production method will facilitate future large scale purification of HIV inhibitor proteins. 

Jim Mendez Lopez

     Major: Mechanical Engineering

     Home City: Garden Grove, CA

     Contact: jemendezlopez@ucmerced.edu

     Faculty Mentor: Professor Asmeret Berhe

 

Jim Mendez Lopez is a second year undergrad student majoring in Mechanical Engineering.  He is interested in research involving sustainable energy and new renewable energy resources.  Jim expects to graduate in Spring 2016.  In his spare time, Jim enjoys playing soccer and is also a part of UC Merced’s Men Soccer program. 

Assessing Soil Nutrient Fluxes and Ecosystem Health From Affected Areas of the Rim Fire

Jim Mendez-Lopez1, Louis Mielke2, Rebecca Lever1, Asmeret Asefaw Berhe1; 1University of California, Merced, 2University of Minnesota

Fire is an important perturbation that controls ecosystem health. Specifically in soil, fire can lead to loss of organic layer and biogeochemical cycling of essential elements. The Rim Fire occurred in the Sierra Nevada Mountains of California in August of 2013. In this study we investigated the role of the Rim Fire in lateral mobilization of topsoil and associated soil carbon and nitrogen stocks from hillslopes that were burned. Samples were collected from sediment fences that were put in medium and high slope sites burned by moderate and high severity fires and from slopes in different landform positions in the area. We analyzed the mass of sediment mobilized and compared sediments from the different positions in terms of soil color, pH, gravimetric water content, particle size distribution and nitrogen and carbon content. We also measured bulk density in the source hillslope soils. We found that in all slopes and fire severities sediment samples decreased in mass over monthly increments between February and May, with soil color also shifting from black to dark reddish brown, and pH measurements showed a trend in slightly decreasing values. This suggests that early deposits remove burned soil and could possibly store pyrogenic carbon. With the collection and analysis of more data we will be able to understand and model the carbon cycling in ecosystems affected by fire, erosion, or both.

Gema Rodriguez

     Major: Biological Sciences

     Home City: Compton, CA

     Contact: grodriguez26@ucmerced.edu

     Faculty Mentor: Professor Masashi Kitazawa

 

Gema Rodriguez is a third year undergraduate student majoring in Molecular Cell Biology.  She is working iwht Dr. Masashi Kitzawa conducting research to investigate the role of VCP and its diseases.  Her research will focus on how muscle-like cells respond differently to stress in the presence or absences of VCP mutations and how those changes lead to muscle degenerative diseases.  Gema expects to graduate in the spring of 2016 with a Bachelors of Science.  After her undergraduate career, Gema hopes to obtain a Ph.D. and conduct clinical research or attend medical school and become a neurosurgeon.  Apart from research Gema also works as a student athlete-learning assistant, tutoring in various subjects including biology, chemistry and Spanish.  She believes her job is very important because she helps fellow students build the foundation necessary for future classes.  In her spare time, Gema enjoys volunteering at Mercy Hospital, exercising, playing soccer, backpacking, and spending time with her friends and family. 

Disease-relevant mutant VCP dysregulates NF-κB activation and upregulates the expression of ubiquitin E3 ligases, Murf1 and Atrogin1, in C2C12 myoblasts

Gema J Rodriguez, Julio C Flores, Carlos J Rodriguez-Ortiz, PhD, Masashi Kitazawa, PhD; School of Natural Sciences, University of California, Merced, Merced, CA

Inclusion body myopathy with Paget’s bone disease and frontotemporal dementia (IBMPFD) is an autosomal dominant disease caused by mutations on the valosin-containing protein (VCP) gene.  Over 80% of patients with VCP mutations develop progressive muscle degeneration.  Its underlying pathogenic mechanisms, however, remain largely unknown. Previously, we have shown that disease-associated mutant VCP prolongs NF-κB activation in C2C12 myoblasts following an acute LPS stimulation. We hypothesize that the impaired resolution of NF-κB activation leads to aberrant transcriptional alterations, including up-regulation of inflammatory-related genes and muscle-specific ubiquitin ligases, which further promote degeneration of muscle cells.  We examined the changes in muscle-specific ubiquitin E3 ligases, Murf1 and Atrogin1, following acute LPS exposure to C2C12 cells. Our preliminary data indicates an increased expression of Atrogin1 and Murf1 protein levels after NF-κB activation. To test whether VCP mutation exacerbates the expression of Atrogin1 and Murf1, we transfected C2C12 cells with wild type VCP or mutant VCP. Transfected cells were incubated for 1 hour with 1 μg/mL LPS as NF-κB activator, followed by 1-hour incubation for recovery without LPS. We expect greater protein levels of Atrogin1 and Murf1 in mutant VCP that may help to understand the underlying mechanisms of muscle degeneration in IBMPFD patients.

Markus Walker

     Major: Computer Science and Engineering

     Home City: Castaic, CA 

     Contact: mwalker3@ucmerced.edu

     Faculty Mentor: Professor Mukesh Singhal

 

Cloud Computing: Benefits, Concerns, and Applications

Markus Walker, Mukesh Singhal, PhD., School of Engineering; University of California, Merced

Cloud computing is a way of delivering a seemingly infinite collection of hardware and software resources to customers as needed, with support for elastic resource provisioning and release, and ubiquitous access to the resources. Industry adoption of cloud computing is maturing at a rapid pace due to its benefits over traditional in-house information technology (IT) systems and services. Some of these benefits include the following: cost savings, fast deployment, scale/elasticity, consolidation, energy savings, elimination of capital expenses, resilience, redundancy, security and competitiveness. Although cloud computing has been shown to be very effective, there are many concerns with its daily usage. Recurring concerns come in various forms of data privacy as well as data security. Interesting enough, these are not new problems, but become more apparent in cloud computing. The focus of this presentation is to provide a general background on cloud computing. Firstly, I give a clear definition of cloud computing. From there, I explain the advantages the cloud brings and how it is applicable. From there, I will go over some of the technologies the cloud brings. Lastly, I will discuss data privacy and data security concerns across multiple scenarios and they're important issues.

 

2013-2015 Cohort

Arthur Chow

     Major: Biological Sciences

     Home City: Tracy, CA

     Contact: achow4@ucmerced.edu

     Faculty Mentor: Professor Jennifer Manilay

 

Arthur Chow is a third-year undergraduate student majoring in molecular cell biology. He works with Professor Manilay, whose research focuses on the development of B-lymphocytes in mice and how they fare during hematopoiesis. Arthur expects to graduate in Spring 2015. After his undergraduate career, Arthur hopes to either obtain a Ph.D. and perform clinical research, or attend medical school and eventually become a pediatrician. Aside from research, Arthur also works in the admissions unit of UC Merced as a Bobcat caller assisting incoming freshman with any questions or concerns about the university. He especially enjoys this job because he feels it is important to help inexperienced students get prepared for the challenges that arise during their undergraduate careers. In his spare time, Arthur enjoys running, playing soccer, solving Rubik’s cubes and assembling computers. He also enjoys going home and spending quality time with his sister and parents on the weekends.

Analysis Of Immune System Cells In Sclerostin-Deficient Mice

Arthur Chow*, Larrisha Coney*, Yvette Pellman, bachelor’s of science, and Professor Jennifer O. Manilay, molecular and cell biology

*equal contribution

When sclerostin (SOST), an essential glycoprotein for proper bone formation, is absent, hyperactive bone growth occurs along with a decrease in bone marrow cavity size. Recent studies have shown that Sost has significant influence over developing bone marrow environments that sustain B cells; however knowledge of its role in B cell function is limited. We are investigating the effects of age and gender on B cell function in Sost-knockout mice. Peripheral blood samples will be analyzed at set time points to observe changes in mature and immature B cell populations in Sost-knockout and B6 mice. We hypothesize that B cell populations will be altered in the absence of Sost, and if so, will raise questions for certain anti-SOST antibody drug treatments of osteoporosis. 

Additionally, we are testing the efficacy of zinc-based fixation for flow cytometric analysis of immune cells in Sost-knockout mice. Zinc-based fixation can reduce research costs considerably, if epitopes are not altered by the fixation. To investigate this, fresh and zinc-fixed splenic cells obtained from a B6 mouse were fluorescently compared by staining them with CD19, CD11b, CD45, Ly-6C, CD4, CD8, and CD11C antibodies. Both cell types displayed similar fluorescence intensity, indicating the possible practicality of zinc-fixation on other cell types. For future experiments, we will test antibody cocktails and apply this method to cells in Sost-KO mice.

Youstina Gad

     Major: Physics

     Home City: Merced, CA

     Contact: ygad@ucmerced.edu

     Faculty Mentor: Professor Michael
     Scheibner

 

Youstina Gad is a third-year undergraduate student in physics. She researches quantum dot molecules and their possible implications on future technologies. She also serves as a Sunday school teaching assistant working with preschool kids and translating between English and Arabic. She came from Egypt in 2008 in pursuit of a better education and better opportunities to serve the community. She values community service and feels it is the most effective way to influence society. She hopes to work in a position that helps people and values science.

Measuring Dipole-Dipole Interaction in Biexcitons in InAs/GaAs Quantum Dot Molecules

Youstina N. Gad, Mark Kerfoot, Cyprian Czarnocki, Davis Lu, Christopher Bush and Professor Michael Scheibner, School of Natural Sciences

Quantum dots have an inherent inhomogeneity due to lack of human control of their exact growth. Basically, no two dots are alike. This inhomogeneity makes it difficult to couple dots together in a way one would couple atoms to form a molecule. Therefore, to control such a system, one needs to device a different way of interaction that is independent of structural details. Electric fields, for example, provide such a mechanism. Here we aim to optically measure the dipole-dipole interaction between two excitons that occupy separate quantum dots in a closely spaced quantum dot pair. The optical transition, with the two excitons, is similar to the neutral exciton transition, but with a slight change in the energy, that is due to the dipole-dipole interaction between the two excitons. We determine the dipole-dipole interaction by a comparative measurement between the transition energy of the state with one exciton, and the state with an exciton in each dot. This measurement will then be usable in controlling a system of coupled quantum dots, so called quantum dot molecules, for use in quantum information processing and in the creation of logic gates implemented as optical switches.

Charlesice Hawkins

     Major: Biological Sciences

     Home City: Alliance, OH

     Contact: chawkins2@ucmerced.edu

     Faculty Mentor: Professor Masashi Kitazawa

 

Charlesice Hawkins is pursuing two bachelor’s of science degrees, in cognitive science and human biology. She expects to graduate in Spring 2015 and continue on to graduate school to obtain her Ph.D. in neuroscience. She has had experience working in a computational cognitive neuroscience lab and is involved in a molecular biology lab. She intends to examine the molecular mechanisms of different neurological disorders. In her spare time, she enjoys quad skating as a roller derby referee.

Evaluating Brain Pathology in a Rat Model of Type II Diabetes Mellitus: a Possible Link with Alzheimer’s Disease

Charlesice C. Hawkins, Carlos Rodriguez-Ortiz, Ph.D., Ruben Rodriguez, Professor Rudy Ortiz and Professor Masashi Kitazawa, School of Natural Sciences

Type II diabetes mellitus (T2DM) is a fast growing disease, as more than 20 million people are affected in the U.S. It occurs when the body develops a resistance against insulin and does not properly utilize glucose.  Insulin resistance and other comorbidities of T2DM such as hypertension, inflammation and increased oxidative stress may damage blood vessels in the brain. Approximately 60-70 percent of T2DM patients develop neuropathic conditions, and it has also been listed as a risk factor for Alzheimer’s disease (AD).  However, the exact molecular link between T2DM and AD has not been fully elucidated. To investigate this connection, brains from a Cholecystokinin-1 (CCK1) receptor mutant rat model for type II diabetes and obesity were examined using biochemical and histological techniques in search of features of AD-like neuropathology. This rat model develops a metabolic syndrome characteristic of T2DM in an age-dependent manner.  In the present study, oxidative stress, amyloid-precursor protein (APP), inflammation, and synaptic markers were examined. There were slight increases in inflammation and APP in the brain of T2DM rat model, suggesting that T2DM phenotypes may trigger AD-like neuropathology at later ages. In perspective of such trends, longitudinal examinations of brain pathology of this model will further provide insights into the molecular link between T2DM and AD.

Kimberly Nguyen

     Major: Chemical Sciences

     Home City: Sunnyvale, CA

     Contact: knguyen44@ucmerced.edu

     Faculty Mentor: Professor Patricia LiWang

 

Kimberly is a third-year undergraduate student majoring in chemistry. She is involved with Professor Patricia LiWang’s lab, which is studying chemokines and their role in HIV entry inhibition and anti-inflammation, and is under the instruction of post graduate Li Zhang. Through hard work and perseverance, Kimberly intends to graduate with her degree in Spring 2015. Growing up as the eldest child of three in a home with only one parent, she has learned how to motivate and push herself to achieve more. She truly believes one’s future will be determined by one’s will and efforts.

Sub-cloning of Highly Potent HIV Inhibitors 5P12 RANTES and 5P12 RANTES-Linker-C37 into Pichia Pastoris Overexpression System

Kimberly Nguyen, Megan Schill, Li Zhang and Professor Patricia LiWang, School of Natural Sciences

HIV plagues approximately 34.2 million people worldwide and 2.5 million new HIV cases were discovered in 2011 alone. Currently, there is no approved cure but progress has been made towards HIV prevention. The proteins 5P12-RANTES and 5P12-Linker-C37 have been shown to be potent HIV entry inhibitors. These inhibitors bind to chemokine receptor CCR5 embedded in the cell membrane of T cells, and the linked C peptide moiety of 5P12-Linker-C37 also binds to the HIV protein gp41, to prevent conformational changes necessary for the entry of HIV into the cells. Presently, these proteins are being studied for possible use in animal and clinical trials. However, protein production of these inhibitors using Escherichia coli has resulted in low yield. We hypothesize that utilizing a eukaryotic overexpression system, Pichia pastoris, will increase protein production.  For this reason, molecular biological techniques including PCR, restriction enzyme digestion, ligation, and transformation were used to sub-clone the DNA sequences encoding 5P12-RANTES and 5P12-Linker-C37 from a pET28a E. coli vector into a pPICZα vector. The product vectors have been sequenced to check for proper insertion of the gene and will be used for later integration into Pichia pastoris for a series of expression tests.

Nicholas White

     Major: Bioengineering

     Home City: Garden Grove, CA

     Contact: nwhite6@ucmerced.edu

     Faculty Mentor: Professor Kara McCloskey

 

Nicholas White, called Nick for short, is a junior in bioengineering and researches tissue engineering, looking specifically at vascular growth and production to see if there is a way to manipulate the vascular growth for diseases such as cancer and a few brain disorders. He expects to graduate in Spring 2015. Nick has spent a few years serving on management teams and has been developing professional skills that he hopes to one day take into industry as he hopes to design a cost effective way to treat many diseases. Nick believes in making his mark through community service, and hopes to change the lives of many through medical, social and economic means. He works with the National Society of Black Engineers to help the community, serving as the Northern California Zone chair, and is a representative for the pre-college, college and professional chapters. He enjoys traveling, learning and working on stuff that is interesting.

Site Directed Differentiation of ESC-EC Using a Fibronectin-VEGF Matrix Blend

Drew E. Glaser1Nicholas S. White2, Professor Kara E. McCloskey1,2; 1Biological and Small-scale Technologies graduate group, School of Engineering

It has been observed that fibronectin (Fn) contains binding sites for vascular endothelial growth factor (VEGF), and may aid VEGF-activated differentiation of embryonic stem cells (ESCs) in to endothelial cells (ECs).  Moreover, directed VEGF-Fn binding may be used in a less complicated and more cost effective approach to site-directed differentiation  such as “click chemistry.” Therefore, we examined the extent of the physical binding between soluble VEGF and Fn. and After verify the binding between VEGF and Fn, we then determined the correlating number of vascular progenitor cells, by measuring Flk-1 expression after four days in induction from ESC in our patented serum-free induction medium. Preliminary data indicates that the VEGF does bind to sites in the fibronectin matrix. After quantifying this phenomenon, we have examined that this growth factor-matrix blend may be used to enhance site directed differentiation of ESC-EC.