Spring 2013 Science Seminars

Development of the intervertebral discs

Dr. Brian Harfe
Director, Program in Developmental Genetics
University of Florida, College of Medicine

Hosting Dept: Biology



Abstract:  Identifying the molecular pathways required for forming the intervertebral disks. An unfortunate consequence of aging is the eventual failure of tissues and organs, which leads to pain, loss of mobility and eventually to death. A tissue that commonly deteriorates in older vertebrates is the intervertebral disks (located between the vertebrae along the spine). Age-related changes in the intervertebral disks are thought to cause most cases of back pain. Presently there is no cure for disk degeneration. In our laboratory we are investigating the cells and genes responsible for disk formation. The long-term goal of this project is to develop cell-based therapies to heal damaged and/or degrading disks in humans.

Currently, there are two disc projects ongoing in my laboratory. The goal of the first is to identify the cells that form the intervertebral discs and the role the hedgehog signaling pathway plays in disc formation. The second project is investigating the mechanical mechanisms responsible for disc formation during development. In addition, we have recently determined that the embryonic notochord forms the middle part of the disc called the nucleus pulposus. We have purified these cells and are currently assaying their ability to heal damaged discs using a mouse model.


Thursday, January 17, 2013 4pm

RFID Tag Could Mean the End of Bar Codes?

Dr. Haiquan (Victor) Chen
Valdosta State University

Hosting Dept: Dept. of Mathematics and Computer Science


Abstract:  The past few years have witnessed the emergence of an increasing number of applications for tracking and tracing based on Radio Frequency Identification (RFID) technologies. However, raw RFID readings are usually of low quality and may contain numerous anomalies. An ideal solution for RFID data cleansing should address the following issues. First, in many applications, duplicate readings of the same object are very common. The solution should take advantage of the resulting data redundancy for data cleaning. Second, prior knowledge about the environment may help improve data quality, and a desired solution must be able to take into account such knowledge. Third, the solution should take advantage of physical constraints in target applications in order to elevate the accuracy of data cleansing. There are several existing RFID data cleansing techniques. However, none of them support all the aforementioned features. This talk focuses on a novel Bayesian inference-based framework for cleaning RFID raw data.

Thursday, January 24, 2013 4pm

Cycles in Music and the Mathematics of Rhythm
Subtitle: Musings of a Mathemusician

Dr. Shaun Ault
Valdosta State University

Hosting Dept: Dept. of Mathematics and Computer Science


Abstract:  We know that sound, and hence music, travels as vibrations in the air. The frequency of cycles in the vibration determines the pitches that are heard. As the number of cycles per second decreases, that is, the time between cycles increases, pitch becomes texture, and texture becomes rhythm. In this talk, I will discuss some of the properties of pitch, texture, and rhythm from a mathematical point of view. We will see and hear what happens as cycles of different frequencies are combined, giving harmonies and poly-rhythms. And we will expand our musical palettes by listening to excerpts of music from many different sources.

Thursday, January 31, 2013 4pm


Developing sustainable water-use solutions for agriculture: manipulating crop physiology to increase drought tolerance

Dr. Diane Rowland
University of Florida

Hosting Dept: Biology



Abstract:  Water scarcity is becoming the critical limitation to sustainable agricultural yields worldwide. However, breeding for drought tolerant crops has proven extremely challenging given the complex traits involved in susceptibility to water stress as well as the diverse states that drought can encompass. It is difficult to define drought tolerance when this condition can take the form of season long severe drought to punctuated periods of low water availability throughout the growing season. Another tool that may prove useful in developing high water-use efficient cropping systems is to capitalize on manipulating crop physiology to better acclimate and sustain crop response to low water during the growing season. Several management techniques have been found to elicit beneficial drought tolerant responses in crop species and these are being tested for their applicability in the southern US cropping environment. These include the use of conservation tillage as well as a regulated deficit irrigation treatment we term “primed acclimation” (PA). PA involves the use of mild water deficits during vegetative crop growth and then the restoration of full irrigation during reproductive development. Conservation tillage has many benefits including increasing soil organic matter, water holding capacity, and plant available water. PA has been shown to increase rooting architecture, water-use efficiency, and drought tolerance. The implementation of these management tools will be discussed as well as their impact on basic crop physiological processes.


Thursday, February 7, 2013 4pm


Regional Drawdown of the Floridan Aquifer: Effects on Spring Flows

Dr. Robert Knight,
Director of the Howard T. Odum Florida Springs Institute

Hosting Dept: Biology



Abstract:  The Floridan Aquifer System (FAS) underlies about 100,000 square miles of Florida, southeast Georgia, Alabama, and South Carolina. Estimated pre-development groundwater discharge from this massive water-bearing geological formation was about 13 billion gallons per day (BGD). Nearly 4 BGD is currently being extracted by wells from the FAS for human purposes. While this groundwater extraction is supporting extensive agricultural, industrial, and urban development in north Florida and south Georgia, it is resulting in unsustainable drawdowns of the surface of the FAS. The average FAS level has fallen by 60 to more than 90 feet near coastal pumping centers. These drawdowns are reversing groundwater flow directions and diminishing the size of groundwater basins feeding important springs and rivers, resulting in significant ecological changes. A regional approach to reduce the overall groundwater extraction from the FAS will be needed to restore adequate groundwater levels and to replenish in-stream flows in springs and rivers.


Thursday, February 14, 2013 4pm


Development of Self-Driving Vehicles

Dr. Carl D. Crane III, Professor of Mechanical Engineering,
Center of Intelligent machines and Robotics
University of Florida

Hosting Dept: PAGE, Engineering Studies program



Abstract:  The presentation describes the development of an autonomous ground vehicle that is capable of traveling on urban streets at speeds up to 40 miles per hour. A hybrid Toyota Highlander has been automated and instru¬mented with pose estimation (GPS and inertial) and object detection (vision and ladar) sensors. This sensor data is integrated to form a Local World Model which represents the environment within 160 meters of the vehicle. The model specifically maps obstacles that must be avoided, the smoothness of terrain, the lane centerline relative to the vehicle, and the location and velocity of moving objects. Vehicle behavior is determined based on this information and the user specified mission file. The behavior arbitration is implemented via the Adaptive Planning Framework which was developed by researchers at the University of Florida. This framework provides a means for situation assessment, behavior mode evaluation, and behavior selection and execution. The architecture is implemented on a system distributed over ten dual-core computers that intercommunicate via the Joint Architecture for Unmanned Systems (JAUS) version 3.2 protocol. The processes that perform the tasks associated with perception, data integration, planning, and control are described in detail together with their design rationale. Finally, the results of system testing and evaluation are presented.


Thursday, February 21, 2013 4pm

An Assessment of the Anthropogenic Affect of Bridges on Fish and
Macroinvertebrate Assemblages

Charles Wright
Department of Biology
Valdosta State University

Hosting Dept: Biology



Abstract:  Anthropogenic impacts such as bridge sites can greatly alter established streambed morphology and associated ecology. At bridge sites, streams are often channelized approaching the site and deep pools are created at the bridge site causing ecological disturbances of fish and invertebrate assemblages. However restoring channels and reducing negative anthropogenic practices allows the return of natural habitats that are likely to include more sensitive species. Recent conservation studies have suggested that sites of anthropogenic origins may serve as potential habitats for reestablishment of populations following a drought event. We examined fish and macroinvertebrate assemblages, and physiochemical factors associated with these assemblages, at 14 bridge sites involving first through fourth order streams. Fish assemblages were least diverse upstream of bridge sites, most diverse at bridge sites and intermediate downstream of bridge sites. Macroinvertebrate assemblages did not exhibit as distinctive a pattern as did fish assemblages. Upstream macroinvertebrate assemblages were less diverse than bridge site and downstream assemblages, a pattern that was only disrupted for the bridge site by third order stream data. The results from this study suggest that bridge sites, if properly engineered, can serve as valuable refuges for reestablishing fish and macroinvertebrate assemblages up and down stream after events such as the severe drought that impacted South Georgia in 2011.


Thursday, February 28, 2013 4pm


Disease Control in the Peanut, a Genetic Approach

Dr. Renée S. Arias
Molecular Plant Pathologist USDA-ARS-National Peanut Research Laboratory Dawson, GA

Hosting Dept: Biology


Abstract:  Information about microsatellite development and how to choose the most effective ones will be presented. Two approaches for aflatoxin control in peanut (phytoalexins and RNA interference) will be discussed.


Thursday, March 7, 2013 4pm


Josh Salter
Department of Biology
Valdosta State University

Hosting Dept: Biology



Abstract:  Aquatic vegetation provides multiple resources such as shelter, food, and breeding habitats for many fish species. Fishes that occupy habitats with similar ecological characteristics are described as fish assemblages. However, not all vegetation offers the same set of resources, and therefore, we hypothesized that not all fish assemblages that occupy aquatic vegetation are identical. Based on vegetated structure complexity occupying the water column, we predicted that submergent vegetation would contain the most diversity. This study involved an analysis of fish assemblages at 18 vegetated lentic sites in South Georgia. Total area, percent vegetated surface area coverage, water volume, and major plant species as well as other physicochemical data were recorded for each locality. Comparative analysis of each location was conducted using, Freidman test, Principal Component Analysis (PCA) and multiple linear regression analyses. Thirty-two fish species were collected across all sites, and significant differences in fish assemblages existed between sites. Defining factors related to assemblage structure was conductively and slope of the study site, but not surface area covered by vegetation as hypothesized. PCA identified Gambusia holbrooki, Leptolucania ommata, Elassoma zonatum, and Aphrododerus sayanus as principal species defining fish assemblage structure.


Thursday, March 14, 2013 4pm

Spring Break Week

Thursday, March 21, 2013 4pm


GA Academy of Sciences Meeting

A Neuroscientist’s Quest to Reverse Engineer the Human Brain- Mapping the Human Brain Connectivity  

Dr. Paul Richard Carney, M.D.
Wilder Professor, Pediatrics Dept., College of Medicine
University of Florida

Joint Sponsors: VSU Science Seminar and Georgia Academy of Science

Hosting Dept: PAGE, Engineering Studies Program



Abstract:  The connectome refers to the exquisitely interconnected network of neurons (nerve cells) in your brain. Like the genome, the effort to map the connectome and decipher the electrical signals that generate your thoughts, feelings, and behaviors has become possible through development of powerful new tools and technologies. For some time, neuroscientists have been able to infer loosely the main functions of certain brain regions by studying patients with epilepsy, head injuries, brain tumors, or by measuring levels of oxygen or glucose consumption in healthy people’s brains during particular activities. But all along it’s been rather clear that these inferences were overly simplistic. Now, new advances in computer science, math, and imaging, and data visualization are empowering us to study the human brain as an entire organ, and at a level of detail not previously imagined possible in a living person. Using a combination of non-invasive imaging technologies, including functional MRI, MEG and EEG, diffusion MRI, optical imaging, and optogenetics, mapping large brain systems can be divided into anatomically and functionally distinct areas, rather than mapping individual neurons. I will review these emerging technologies and show results for mapping the brain in animal models and humans.


**Note room & date change**

Bailey Science Auditorium

Friday, March 29, 2013 3pm


How ZuChongzhi derived the volume of a sphere from the results of Liu Hui

Dr. Iwan Elstak
Valdosta State University

Hosting Dept: Mathematics and Computer science



Abstract:  Around the fifth century AD the mathematician, astronomer and calender scholar of ancient China, Zu Chongzhi used a commentary and results from the third century genius Liu Hui, to derive the correct formula for the volume of a sphere, using the principle of Cavalieri (known in China, centuries before Cavalieri bas born). His derivation was totally rigorous and correct.It showed the power and level oflogical deduction andmastery of complex mathematics achieved in early Chinese culture.


Thursday, April 4, 2013 4pm

The evolution of gametic incompatibility: Does reinforcement drive positive selection in a sperm binding protein in Mytilus?

Dr. Matt Gilg
University of North Florida

Hosting Dept: Biology



Abstract:  Speciation in many marine invertebrates is thought to involve the evolution of gametic isolation, where sperm of one species are inefficient at fertilizing eggs of another species. Gametic isolation is thought to be due to divergence of gamete recognition proteins expressed on the surface of eggs and sperm. These gamete recognition loci often evolve very quickly and show patterns of positive selection, and while several hypotheses have been proposed that could result in the observed patterns the driving force of divergence for many of these loci is unknown. I tested the hypothesis that positive selection at the sperm locus M7 lysin in blue mussels is the result of reinforcement. Mytilus edulis and M. galloprovincialis are two species of blue mussels that hybridize along the Atlantic coast of Europe and hybrids often show lower fitness. This is predicted to favor the evolution of pre-zygotic barriers to reproduction such as gametic isolation. I will present data on the geographical patterns of M7 lysin allele frequencies throughout the mosaic hybrid zone between these two species to determine whether a pattern of reproductive character displacement exists. Then I will discuss the results of fertilization experiments in which males with different genotypes at M7 lysin attempted to fertilize eggs from each species to determine if certain alleles reduce the likelihood of hybridization.


Thursday, April 11, 2013 4pm

The Molecular Mechanism underlying our Daily Physiology

Dr. Choogon Lee
College of Medicine
Florida State University

Hosting Dept: Biology



Abstract:  We study the circadian clock, a biological oscillator that controls daily variations in many bodily functions, such as the sleep-wake rhythm, using the mouse as a model system. The field of circadian biology is one of the most active and visible in the biological sciences, and the importance of circadian rhythms in every organism, including humans, is now clearly recognized. Temporal variations in energy and hormone levels, and in aspects of disease (e.g., the increased incidence of heart attacks in the early morning hours, and the nocturnal exacerbation of the symptoms of asthma) reveal the prominent influence of the biological clock on both physiology and pathophysiology. The current understanding is that the circadian clock is a self-sustaining molecular oscillator that has a period of ~24 hours and that can be phase-shifted by environmental stimuli, most notably the day/night cycle. I will describe how our studies have contributed to the current understanding of the clock mechanism.


Thursday, April 18, 2013 4pm

The Breeding and Business of the Encore Azalea

Robert "Buddy" Lee
Director of Plant Innovations for PDSI

Hosting Dept: Biology



Abstract:  Robert "Buddy" Lee is a nationally known plant breeder and currently serves as Director of Plant Innovations for PDSI, the new plant innovation company that manages the Encore® Azalea and the SouthernLiving® Plant Collection.
Buddy is one of the most respected plant breeders and horticulturalists in North America, with over 30 years’ experience in nursery management, breeding, propagation and new plant development. He is active in numerous organizations, including the Azalea Society of America, the International Plant Propagators Society, and the Louisiana Nursery and Landscape Association” (www.encoreazalea.com).


Thursday, April 25, 2013 5pm

in the Student Union Theater