Lyman T. Johnson Postdoctoral Fellows
María Luz García works in the Ixhil Maya region of Guatemala. Her research is concerned with how Ixhil speakers make use of the resources of their language in order to construct and reflect social realities. In particular, her work is concerned with the expression of historical memory of the recent period of violence in Guatemala in various Ixhil genres of speech. This research includes linguistic description of the Ixhil language, linguistic and ethnographic characterization of indigenous ways of speaking, and attention to the social and political realities of historical memory in the Guatemalan context. It has implications for understanding practices of community formation in Maya regions, how periods of violence are incorporated into local understandings of history and how language use constitutes social and political action.
Mayra Tovar (Theoretical Condensed Matter): Iridates, iridium-based transition metal oxides, are materials involving 5d-orbital electrons. Compared to the case of 3d systems, the 5d orbitals of these materials are more spatially extended, resulting in reduced electronic correlations. This, in turn, gives the naïve expectation of iridates being in a metallic state. However, the interplay of correlations and strong spin-orbit coupling – a central, distinguishing feature of these systems – gives rise to numerous novel states of matter. The focus of this research has been on Na2IrO3, a layered system in which the iridium ions form a honeycomb lattice. Here, too, each iridium ion finds itself surrounded by an oxygen octahedron. The objective of the study is to determine the strength of the spin-orbit coupling in this material, as well as the splitting of the energy levels caused by a trigonal distortion in the oxygen octahedra. We do this by developing a model for the magnetic susceptibility in a high-temperature regime, with a direct comparison to experimental measurements.
Leonardo Marazzi (Mathematics) works on scattering theory manifolds, which are mainly hyperbolic-like. The main focus of his research is the study of resonances, which are poles of the resolvent. Typical questions are the classification of these poles, finding regions free of resonances, counting number of resonances in regions by obtaining lower and/or upper bounds on the number of resonances and inverse scattering theory. The latter refers to obtaining information on the geometry or/and the potential (for a Schroedinger operator) from a boundary operator at one or multiple engergies. This type of analysis has connections to physics, particularly to quantum mechanics, general relativity and string theory. Particularly the type of manifolds he studies are Schwarzchild-like manifolds and the AdS/CFT correspondence in quantum gravity is based on the principle that far field phenomena are related to conformal theories at the boundary of the mainifold at infinity.
Christopher Olds (Political Science) explores how groups can alter their decision-making in the face of changes in information cues available in the political environment. His current focus in examining this topic is to determine if the usage of a specific emotional tone in issue discussion by political elites can shift public opinion, as well as the views of other elites. Christopher's dissertation addresses whether the way in which political elites discuss an issue can change the perceived salience of that issue. The project evaluates the issue discussion of both formal (the president) and informal (the mainstream media) elites. As a fellow, he intends to look further at questions pertaining to how information cues being offered by political elites can modify the decision-making process of the public.
Rosana Grafals-Soto (Geography) is interested in coastal geomorphology and biogemorphology. Her research focuses on the interaction between dune forming geomorphic processes and dune vegetation growth. A low wave energy tropical beach/dune environment in Manatí, Puerto Rico will be studied to analyze the relationship between dune vegetation density and beach width. The beach is the main source of landward sediment transport, which is one of the main factors causing stress on dune vegetation growth. The narrow low wave energy beach at Manatí provides a limited sediment source, less sediment transport and, consequently, a decrease in stress levels which may lead to an increase in vegetation density. Because of the potential of dunes to protect landward coastal settlements against coastal flooding, it is important to understand the processes that affect the form and function of dune systems, especially those related to vegetation which provides stability to the system.
Adolphus G. Jones (Organic Electroactive Materials) focuses on the synthesis and characterization of new carbon-based molecules for semiconductor applications. The active elements of light emitting diodes, organic transistors, and photovoltaic (solar) cells are based on organic small molecules and polymers. Traditional organic synthesis is combined with control of solid-state order to optimize the charge transport properties of these molecules. In particular, substituted aromatic and heteroaromatic compounds will be synthesized, their solid-state organization observed, and electron and hole mobilities measured. The materials can then be incorporated into organic semiconductor devices. The development of lightweight, flexible, and efficient solar cells and organic transistors is a primary target of this research.
Trushna Parekh (Geography) studies the cultural transitions and transformations associated with gentrification. Her research focuses on how longstanding residents of a gentrifying neighborhood negotiate the onset and impacts of gentrification. While gentrification has long been understood to effect changes in property values and resident composition, the perspectives of longstanding residents have been neglected. Through an ethnographic study of the Tremé neighborhood in New Orleans, she examines how the process of gentrification is experienced in the everyday lives of such residents. Her work investigates how spatial practices, racialized identities, cultural memory, and the politics of belonging have unfolded as Tremé has gentrified. As a postdoctoral fellow working with Michael Crutcher (Geography), she will continue her research on gentrification in Tremé within the context of the rebuilding of post-Katrina New Orleans.
Dominique Talbert (Pharmaceutical Sciences) is interested in the effects of glucocorticoids on the efficacy and toxicity of chemotherapeutic agents. Glucocorticoids are currently widely used in combination with many chemotherapeutic agents for the treatment of cancer. However, although some labs have shown that glucocorticoids can enhance the effectiveness of chemotherapy, others have shown that they can cause resistance. It is critical to understand the reason for the discrepancies of glucocoricoids’ effects on these agents since many patients could potentially be affected. We propose that the disparity in the effect of glucocorticoids on chemotherapeutic agents is due to the different treatment approaches used in different studies. While some groups use only 1 hour pre-treatment with glucocorticoids, others use 24 hour, 1 day, or even 5 day pre-treatment. Since there are many known mechanisms of glucocorticoids activation, these administration schedule differences could cause a drastic variation in response. To analyze this, various in vitro, in vivo, and clinical studies will be performed to determine how altering the exposure of glucocorticoids prior to treatment modifies both molecular and physiological response to chemotherapy.
Aminata Cairo (Community and Leadership Development) is interested in addressing issues of mental well being in local communities. More specifically, she approaches mental health from a broad base, including consideration for overall well being, cultural context, spirituality, and indigenous traditions. Through participatory action research methods she will work with the East End community (in Lexington) and other selected populations to develop a trained group of lay community mental well being supporters, and a subsequent training curriculum.
Leon Dyers Jr. (Organometallic Chemistry) tailors titanium catalysts for selective ethylene oligomerization and controlled olefin polymerization. These catalysts are designed to prove useful in the manufacturing of linear low-density polyethylene (LLDPE), a versatile copolymer used in many consumer products. Thus far, the few catalysis systems used for commercial purposes are chromium based. The driving force behind this research is the lack of mechanistic understanding involved in chromium base LLDPE production and the environmental impact of using chromium based systems over less toxic metals. These factors ultimately contribute to the overall cost of LLDPE production. Titanium catalysts are a cost-effective alternative, offering less toxic byproducts than chromium based systems. Different from chromium (I-III), which is paramagnetic, titanium(IV) catalysts are diamagnetic in nature: thus more convenient for study in solution by NMR spectroscopy. These studies will generate a wealth of mechanistic information vital to the optimization of existing systems or the synthesis of new titanium and chromium based catalytic systems.
Sarah Rodriguez Hazelton (Animal and Food Sciences) will investigate the effect of consumption of endophyte-infected fescue on mammary gland growth and development in lactating and pubertal dairy cows. Tall fescue is a very common pasture grass in Kentucky and the eastern northwestern regions of the United States. Fescue is favored for its persistence and drought tolerance, but these benefits are often offset by suppressed immune system, decreased weight gain and decreased milk production in the animal. Reduced performance in animals grazing tall fescue, i.e. fescue toxicosis, is a result of consumption of the ergot alkaloids found in the endophyte-infected plant. There is a paucity of literature which examines the cellular and genetic mechanisms by which ergot alkaloids affect mammary growth and development, thus decreasing milk production. Elucidation of the genetic mechanisms by which consumption of endophyte-infected fescue decreases milk production will uncover ways to offset or alleviate the detrimental effects of ergot alkaloids on the bovine mammary gland. This project will represent a collaborative effort between the University of Kentucky and the USDA, ARS in Beltsville, MD.
Willie Merrell (Supersymmetry) Supersymmetry is a symmetry that relates bosonic and fermionic states of a theory. It is a great theoretical tool for performing calculations that are otherwise intractable. The use of supersymmetry is also a leading candidate for solving a major theoretical problems with the standard model of particle physics, the hierarchy problem, and is a necessary part of superstring theory. His research involves using the natural mathematical language for supersymmetry, i.e. Superspace, to aid in formulating supersymmetric theories and performing calculations in supersymmetric systems relevant to superstring theory and supersymmetric field theory.
Renã Sowell (Biological Chemistry) investigates the protective effects of antioxidant compounds against oxidative stress in neurodegenerative diseases. Key to this work is the use of transgenic animal models, in addition to in vitro studies, for disorders such as Alzheimer’s Disease (AD). The research employs redox proteomics techniques to monitor changes in the levels of protein expression and oxidation in AD animals which have been treated with various antioxidant compounds. Studies of this nature aim to provide insight to biological pathways that are neuroprotected from oxidative stress and to develop antioxidant compounds that are beneficial to neurodegenerative diseases.
Xabier Arzuaga (Animal and Food Sciences) is interested in the biochemical and molecular effects of environmental contaminants in vertebrates. His specific focus is on how cell signaling pathways relate to the toxic effects of chronic exposure to contaminants and how nutrition can affect the exposure outcome in human populations. Current projects involve pro-inflammation and pro-atherosclerosis effects caused by polychlorinated biphenyls (PCBs) exposure and how the toxicity of these chemicals can be modulated by nutrients such as dietary lipids and flavonoids.
Travonia Brown-Hughes (Educational and Counseling Psychology). Research interests are grounded in the study of culture, health disparities and aging in diverse populations. She is currently working towards the construction of a revised measure of African American Acculturation that will include value-based dimensions of African American culture. A revised measure of African American Acculturation will allow researchers to examine the extent to which African Americans endorse traditional values and ultimately gain a more comprehensive understanding of African American culturally situated beliefs and behaviors.
Walter Philip Suza (Plant and Soil Sciences). Sterols (e.g. cholesterol) are essential for all higher forms of living organisms. The role of cholesterol in human physiology is well understood, and the effect of cholesterol on human health is continuing to receive greater scientific and public attention. Plants make more than one sterol, including cholesterol, but the sites of synthesis and mode of transportation of sterols within the plant is not understood. Walter is investigating sites of sterol synthesis and sterol transportation mechanisms in plants using Arabidopsis thaliana and Nicotiana benthamiana model systems.
Gregory S. Parks (Psychology) is interested in the ways in which psychological theory and research help us better understand the relationship between race and law. More specifically, he is interested in how psychology can be used to understand courtroom participants (i.e., judges, lawyers, juries, and witnesses). His current and primary work is an edited book on psychology race, and law.2003 Recipients:
Michael E. Crutcher Jr. (Geography) is interested in the historic development and maintenance of cultural landscapes under changing social, economic and political conditions. Specific issues include the privatization of public space, gentrification and heritage tourism. His current research, under advisor Richard Schein, looks at these issues in the Tremé, a culturally and historically rich, African-American neighborhood in downtown New Orleans.
William C. Hoston Jr. (Physics & Astronomy) works in condensed matter physics, a subject which involves phenomena that emerge when large numbers of systems interact, in particular high-temperature superconductors. Superconductors conduct electrical current without dissipating energy. Until the mid 1980s, all superconducting materials fit within a framework that had been established by the 1960s. However, this framework fails to explain the high-temperature superconductors and research on finding a new way to understand them continues. I pursue this work in conjunction with collaborators at UK (Herb Fertig and Ganpathy Murthy in Physics), Boston University and the Paul Scherrer Institute in Switzerland.
Easton Reid (Cardiovascular Physiology) investigates the role of endogenous opiates and other compounds in myocardial protection. From cardiac myocyte to functional myocardium, these compounds have shown benefit by decreasing ischemia-reperfusion injury, reducing infarct size and improving surgical cardioplegia. The mechanisms underlying such cardioprotection are unknown. During his fellowship, the effects of modulating G-protein coupled receptors and intracellular cascades will be determined. As a result, clinical interventions can be developed to stimulate protective or block detrimental signaling pathways in compromised cardiac conditions.The Spirit and Legacy of Lyman T. Johnson
By filing a federal lawsuit against the University of Kentucky in 1948, Lyman T. Johnson opened a door that thousands of African-American students have walked through. The lawsuit challenged the state's Day Law, the law that prohibited blacks and whites from attending the same schools. In 1998, UK celebrates the 50th anniversary of Johnson's successful challenge.
Johnson had already earned a bachelor's degree in Greek from Virginia Union University and a master's degree from the University of Michigan when he entered UK in 1949 as a 43-year-old graduate student. Although he left UK before earning a degree, the university presented him in 1979 with an honorary doctor of letters degree.
Johnson taught history, economics and math for 33 years at Louisville's Central High School. The civil rights pioneer was a member of the Jefferson County Board of Education from 1978 to 1982.
Johnson--a devout believer that integration was the only path to equity between the races--is celebrated as one Kentucky's greatest fighters for integration. He died at age 91 in 1997. Johnson's determination to break the color barrier has garnered praise from educators everywhere. Beverly Watts, executive director of the Kentucky Commission on Human Rights, said, "He really lived a legacy, and I think we truly have a shining example to follow." At Johnson's death, UK President Charles T. Wethington Jr. praised his courage: "His leadership and courage set the example which has been so successfully carried by thousands of African Americans at the University of Kentucky over the past five decades."