Fall 2013 Science Seminars

All Seminars will be held in Powell Hall Auditorium at 4pm. Powell Hall is located next door to the Bailey Science Center

Between the devil and the deep blue sea: Climate change, sea-level rise, and population growth threaten Florida’s biodiversity The greatest threats to biodiversity in Florida are land-use change, sea-level rise, and climate change. Despite these synergistic threats, little has been done to assess or mitigate impacts at a state-wide scale. We modeled future human population growth, climate change and sea-level rise and assessed the impacts of these three threats to 1,000 rare and imperiled species and 39 natural communities. The impacts of these changes on rare and imperiled species in Florida are dramatic; nearly 30% of species surveyed will have half of their known range directly impacted by inundation or land-use change. Highly imperiled taxa are evenly distributed across taxonomic groups, but 74% are clustered in the Florida Keys and South Florida where low elevation and high levels of endemism increase extinction risk. Niche models for several keystone and indicator species indicate substantial range shifts with increasing temperatures and more seasonally variable precipitation. The future of Florida’s rich biodiversity will depend on management strategies that maintain connected landscapes and support the natural adaptive capacity of species. Dr. Joshua Reece, Department of Biology, Valdosta State University Hosting Dept: Biology	Thursday, Aug. 22, 2013 4pm
Do Antarctic Icefishes with “Gin-Clear” Blood have an Advantage? Channichthyid icefishes (suborder Notothenioidei) are a family of fishes that are found primarily in the stable, cold environment of the Southern Ocean. Icefishes are the only vertebrates that as adults do not express the oxygen-binding protein hemoglobin (Hb) in their blood, and six of the 16 icefish species also lack the intracellular oxygen-binding protein myoglobin (Mb) in their heart ventricle. The iron of the heme prosthetic group of Hb and Mb reversibly binds oxygen and can interact with oxygen to form free radicals that damage macromolecules. Recent results indicate lower levels of oxidized proteins and lipids in white-blooded icefishes compared to red-blooded notothenioids, which may lead to a reduced rate of protein turnover and a lower energetic cost of protein synthesis. The purpose of this talk is two-fold: 1) share the results of experiments that examined the cost of protein synthesis as a function of oxygen consumption in white- and red-blooded notothenioids, and 2) describe my experiences of living and working at Palmer Station, Antarctica. Dr. Theresa Grove, Department of Biology, Valdosta State University Hosting Dept: Biology	Thursday, Aug. 29, 2013 4pm
The Future of Biomedical Engineering** Biomedical Engineering has caught the imagination of millions of people world wide, with spectacular growth in academia and in clinical support industries. This talk discusses the range of biomedical engineering practically and intellectually, including some "light" philosophy and practical guidance for students interested in the field. The talk will then give a gallery of examples of work at the cutting edge — dramatic evidence of the power and breadth of the field and an inspiration to all. It will conclude with a very short introduction to the speaker's work, "Brain on a Chip", where living neurons are cultured on electrode arrays. Dr. Bruce C. Wheeler, Pruitt Family Department of Biomedical Engineering at the University of Florida Hosting Dept: PAGE, Engineering Studies Program	**This seminar will be held in the Student Union Theater Thursday, Sept. 5, 2013 4pm
Rational decision making in irrational circumstances: The case of texting while driving It has been more than 3 years since Georgia enforced a ban on texting while driving. If caught, a motorist could receive a fine of $150 and one point added to their driving record. Observations of drivers were made before and after the ban on texting in Georgia, with additional comparisons to drivers in Florida. Texting-while-driving behaviors have changed, but not stopped since the ban. Dr. Chuck Talor, Department of Psychology, Valdosta State University Hosting Dept: Psychology	Thursday, Sept.12, 2013 4pm
Extinction Rates in North American Aquatic Biotas and Attributes of Extinct North American Freshwater Fishes Dr. Noel Burkhead; USGS Hosting Dept: Biology	Thursday, Sept.19, 2013 4pm
Chelation-assisted, copper(II) acetate-catalyzed azide-alkyne cycloaddition and amine dehydrogenation In this presentation, I will talk about how an accidental discovery in the laboratory has grown into a full-fledged research project that is offering new mechanistic insights and new applications of copper-catalyzed reactions. The discovery of a variant of the copper(I)-catalyzed azide-alkyne cycloaddition reaction will be described first. Copper(II) acetate without the addition of a reducing agent shows a dramatic accelerating effect. The copper(I) catalyst is produced via an inducting alkyne oxidative homocoupling reaction. The preferred azide substrates are those capable of binding the copper center at the alkylated azido nitrogen position via chelation. A mechanistic model accounting for the effectiveness of copper(II) acetate and chelating azides will be presented in the second part. An unsymmetrical bisazide for a chemoselective sequential “click” ligation is developed resulting from the mechanistic understanding of the chelating azide-involved reactions. The mechanistic model of copper(II) acetate catalysis may be extended to other copper-mediated processes, of which a secondary amine dehydrogenation reaction will be described in the last section. Dr. Lei Zhu, Florida State University Hosting Dept: Chemistry	Thursday, Sept. 26, 2013 4pm
Fire over Russia: The Great Chelyabinsk Meteor of 2013 On February 15, at 9:20 AM local time, a fireball brighter than the Sun lit up the skies over Chelyabinsk, Russia. This bolide was caused by a small asteroid, about 60 feet in diameter, entering Earth's atmosphere at a speed of over 40,000 mph and breaking into fragments about 20 miles above the surface. The disruption of this object produced a release of energy of about 470 kilotons, sending atmospheric shock waves ("sonic booms") into the populated areas below. These pressure waves broke glass windows, blew in garage doors, and caused other minor structural damage over a wide area, the extent of which is still being determined. There were over 1600 injuries, most from flying shards of glass. The Chelyabinsk fireball is the most energetic since Tunguska in 1908, which laid waste to a wide area of forest in Siberia. This presentation will give details on this extraordinary, once in 75 year occurrence, and how it may mark a turning point in the study of objects capable of colliding with Earth. Dr. Bill Cooke, Marshall Space Flight Center, Meteorioid Environments Office Hosting Dept: Department of Physics, Astronomy, and Geosciences	Thursday, Oct. 3, 2013 4pm
Reserved Dr. Richard Tyre , Florida State University Hosting Dept: Department of Physics, Astronomy, and Geosciences	Thursday, Oct. 10, 2013 4pm
Expression, Purification, Refolding, and Structural Investigation of the Membrane Protein, Lipoprotein Signal Peptidase (LspA) and its Substrate LpqH by Solution and Solid State NMR The lipoprotein LpqH (Rv3763) is an antigen in mycobacterium tuberculosis. Its N-terminal signal peptide is subject to LspA (Lipoprotein Signal Peptidase) cleavage. Globomycin inhibits the activity of LspA. LpqH is the enzymatic target for LspA, a drug target for M. Tuberculosis. The recombinant protein LspA and LpqH were expressed in Escherichia Coli and LspA was reconstituted with detergent DPC to form LspA-DPC micelles for solution NMR study. Followed by replacing detergent DPC by lipids DMPC/DMPG=4/1 molar ratio, LspA was incorporated into Liposome. NMR gNhsqc was used to monitor the folding of the four forms of LpqH in the lipoprotein processing process. The uncleaved LpqH as a substrate of LspA was used to measure the activity and efficiency of LspA reconstituted either by detergent as protein-detergent micelles or by lipids as protein-liposome. The cleaved signal peptide was extracted from the reaction and quantified, that led to km and kcat parameters. These were further used to judge the efficiency of reconstituted LspA. Finally, the uniformly aligned LspA in lipid bilayer was run on solid state NMR using PISEMAMAS pulse sequence (Polarization Inversion Spin Exchange at the Magic Angle and Magic Angle Sample Spinning) for structural study of LspA Dr. Da Qun Ni; Post-Doctoral Research Associate in Tim Cross Lab, Department of Chemistry and Biochemistry at Florida State University and National High Magnetic Field Laboratory. Hosting Dept: Chemistry	Thursday, Oct. 17, 2013 4pm
Reserved Dr. Joshua King, Department of Biology, University of Central Florida Hosting Dept: Biology	Thursday, Oct. 24, 2013 4pm
Risk Assessment for Nonindigenous Freshwater Fishes in Micronesia Invasive species are considered the second most significant driver of biodiversity loss worldwide and are by far the number one cause on islands. They also have direct negative impacts upon other critical island issues such as food security, culture, natural resources, and economic development. Invasive species are spread, intentionally and unintentionally, by trade, travel, and tourism. All three of these activities are projected to increase significantly in the region of Micronesia, especially Guam and the northern Mariana Islands, as a consequence of diplomatic relations between the United States and Japan, and ongoing and planned realignment of military forces in the western Pacific region. As part of a large-scale interagency effort to develop a comprehensive Micronesian Biosecurity Plan (MBP), we assessed the potential risks posed by the introduction and spread of freshwater organisms in Micronesia, with emphasis on fishes that are extensively utilized in the ornamental pet trade, aquaculture, and food industry. The risk assessment was based on a quantitative analysis of fish introductions to inland waters of Guam and Hawaii. One dependent variable (prior establishment success) and 14 independent variables relating to propagule pressure, life-history attributes, and physiological tolerances, were used to develop 21 a priori and 8 post hoc logistic models to determine probabilities of establishment success. The best model derived from this analysis included three primary factors used to predict establishment success: (1) a random family (taxonomic) effect; (2) prior invasion success on tropical islands or island groups globally, and; (3) hypoxia tolerance. Results of the risk assessment have utility in that the models can be used to assign probabilities of establishment success of species not currently established in Micronesia. A set of management alternatives to mitigate for unwanted introductions or spread of invasive freshwater species was established for an implementation phase of the MBP, as the U.S. Department of Defense proceeds with military activities in the western Pacific. Dr. Stephen J. Walsh, Southeast Ecological Science Center, U.S. Geological Survey, Gainesville, Florida Hosting Dept: Biology	Thursday, Oct. 31, 2013 4pm
Lyme borreliosis in the southern United States Lyme disease(LD) is the most commonly reported vector-borne disease in the United States. The U.S. Centers for Disease Control and Prevention recently estimated that at least 300,000 new cases occur each year (10X the previous estimate). In the southern U.S., LD is significantly understudied, under-reported, often misdiagnosed, and commonly goes untreated. The disease is highly controversial and politicized. Many aspects of LD in the U.S. are still hotly debated, including: (1) the geographic distribution and risk of the disease; (2) the Borrelia species responsible for causing the disease; (3) the tick species responsible for transmitting the infection to humans in different regions; (4) the value of currently recommended diagnostic tests and interpretation criteria; and (5) whether infections can become chronic and persist despite antibiotic treatment. This seminar will summarize what is known about the ecology and epidemiology of LD, the evidence supporting its occurrence in the southern USA, and recent and ongoing studies of human LD in human patients from southern states. Dr. Kerry L. Clark, Epidemiology & Environmental Health, Department of Public Health, University of North Florida Hosting Dept: Biology	Thursday, Nov. 7, 2013 4pm
My Brief Stint in the "Science Wars:" How Cold Fusion, Heidegger, and Dewey Helped Me to Make Sense of it All My journey in the philosophy of science and technology took me in to the so-called science wars in the wake of the much publicized 1996 Sokal Hoax. By examining the technological construction of scientific results, I found that a much needed middle ground can be reached between the naive realism and naive constructivism that seems to dominate much of the discourse on science's epistemic value. This talk will focus on an example of scientific failure, and how attention to science as a technological construct permits a modest realism. Dr. William J. McKinney, President of VSU Hosting Dept: Arts & Sciences	Thursday, Nov. 14, 2013 4pm
*Promoting sustainable agricultural systems with microbial endophytes: The Aspergillus* section Nigri group case** Microbial endophytes, including bacteria and fungi, actively colonize internal plant tissues, developing transient symptomless infections without any immediate damage to the plant host. Some endophytic fungi are a major concern since they are known to produce mycotoxins, a potential threat to humans and animal health. The overall goal of our research program is to gain a better understanding of the fungal biology of the A. section Nigri species that are able to colonize peanut and maize hosts, their endophytic nature, and their capacity to produce secondary metabolites. Our basic hypothesis is that there are species within the Aspergillus section Nigri present as endophytes in kernels and plants of two major agronomic crops, maize (Zea mays) and peanut (Arachis hypogea). Our results suggest that several black aspergilli, including Aspergillus niger and Aspergillus carbonarius, can create endophytic associations with these two important crops. Dr. Edwin Palencia, Research Molecular Biologist, USDA-ARS National Peanut Research Laboratory Dawson, GA Hosting Dept: Biology	Thursday, Nov. 21, 2013 4pm
Thanksgiving Break