COCID CONFERENCE

POSTER SESSION INFORMATION and ABSTRACTS

• Submissions: Please contact Dr. Saziye Bayram at bayrams@buffalostate.edu
• General information: Any work related to the conference theme in progress is eligible for submission. We encourage students and faculty to join us.

 

Abstracts

Title: Developing an Animated Queueing Simulation to Support Instruction in Operations Research: A Comparison of Synchronous and Asynchronous Animation Strategies
Sheldon Tetewsky, Center for Health and Social Research at Buffalo State College, Buffalo 14222

One of the central topics in the field of operations research is queueing theory, which is concerned with predicting the behavior of different types of waiting-line systems. Although most people encounter queues on a daily basis, students often have a difficult time understanding how they operate because their behavior is governed by the interaction of several parameters that are probabilistic in nature. This project is concerned with developing a multimedia queueing simulation that students can use as an instructional aid. In particular, two different approaches to implementing the animation were compared. In the synchronous version there was a direct link between the animation showing customer movement and the initiation of customer waiting, whereas in the asynchronous version the initiation of customer waiting was separate from the animation. A quantitative comparison of these two alternative approaches showed that both versions were able to provide good estimates of the long-term average waiting time.  Some of the implications for this type of simulation within the field of instructional technology were also discussed.

 

Title: The protein hydration transition
Yunfen He, J.R. Knab, J.Y Chen and A.G Markelz
Physics Department, University at Buffalo, Buffalo, NY 14260

We previously reported the hydration transition in the THz dielectric response for native state hen egg white lysozyme (HEWL). As hydration increases the response slowly increases until at 0.25h (gm water/gm protein) the absorbance and index sharply increase. The hydration level coincides with the filling of the first solvation shell. The THz dielectric response arises from relaxational and resonant vibrational response, where the vibrational response corresponds to delocalized structural motions sensitive to the conformation and the environment. We examine the contribution of low frequency vibrational modes to the hydration transition by calculating the normal mode density and dipole moment as a function of solvent content using CHARMM. We find that mode density increasing slightly faster than linear, but only at higher frequencies; while low frequencies are nearly hydration independent. Dipole moment intensity calculation has nearly zero hydration dependence for entire frequency range. The experimental hydration dependence is inconsistent with normal mode calculations. We discuss that another source for the hydration transition in the THz response may be the hydration dependence of the activation energy for solvent slaved side chains fluctuations that contribute to the relaxational response.

 

Title: Experimental design for game playing heuristics
Steve Uurtamo, Mathematics Department, Buffalo State College, Buffalo 14222

Optimal experimental design is extremely useful for placing bounds on the average predicted error between a model function and the data that one is attempting to model. This is often done for industrial processes, but here I have adapted this paradigm to find optimal heuristics for a computer program to play Go.

 

Title: The Creative Scientific Works of Herbert Hauptman
Stephen E. Gareau, Assistant Professor, Department of Computer Information Systems, Buffalo State College

This presentation will examine some of the scientific works of Nobel Laureate Dr. Herbert Hauptman, and also examine the process of how these works came to fruition. In particular, this presentation will examine (a) the phase problem of x-ray crystallography-a chemical crystallography problem that remained unsolved for approximately 40 years before Dr. Hauptman applied mathematical methods to the problem; and (b) the 'Shake-and-Bake' method for determining the molecular structure of larger molecules, by relying on the benefits of a massively parallel supercomputer to provide the enormous computational power required for the solution process. This presentation will also compare Dr. Hauptman's various paths to success with elements of the Creative Problem Solving (CPS) process.

 

Title: Are Lattice Gauge Theories Magnets in Disguise?
Michael Grady, Department of Physics , SUNY Fredonia

It has long been thought that magnetic spin theories, which serve as models of ordinary ferromagnets, and lattice gauge theories, which model the strong nuclear interactions holding the quarks together inside the nucleus are quite different.  The fields are similar, but the interactions in the first have a global symmetry and in the latter a local symmetry.  In the magnetic models the global symmetry is always spontaneously broken, i.e. magnetized, at low temperatures in three or more dimensions.  However, local symmetries cannot break spontaneously, so it is thought that for the gauge theories there is no part of the original gauge symmetry broken at weak coupling.  However, I have found that if the gauge is fixed to Coulomb Gauge, which has the effect of turning the local symmetry into a partially global symmetry, then this remaining remnant symmetry does break spontaneously, and the lattice gauge theory acts much like an ordinary magnet.  Since the number of degrees of freedom change abruptly at a symmetry breaking, it would appear impossible for this not to affect thermal properties.  This happens even for the SU(2) theory which is thought to have no phase transition at all on the infinite 4-d lattice.  Since gauge fixing is known not to affect any of the thermal properties of the theory, this would imply that the local symmetry of the unfixed theory is merely hiding an underlying symmetry breaking from view. The idea that all gauge symmetries may be partially broken at weak coupling has interesting implications for elementary particle physics.

 

Title: Hydration Dependence of the Terahertz Dielectric  Response of Ferri Cytochrome C: Calculations & Experiments 

Jing-Yin Chen, Joseph R. Knab and Andrea G. Markelz,
Department of Physics, The State University of New York at Buffalo, Buffalo, New York, 14260
Phone: 1-716-645-2017 ext122  Fax: 1-716-645-2507  
E-mail: jchen9@buffalo.edu

Susan K. Gregurick
Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, 100 Hilltop Circle,
Baltimore, MD  21250

Terahertz (THz) time domain spectroscopy (TTDS) is sensitive to collective vibrational modes of molecule, reflecting the flexibility of molecule.  Here, we investigate how hydration affects those low frequency vibrational modes for ferri-cytochrome c.  The THz dielectric response of oxidized cytochrome c films not only increases with increasing frequencies at each hydration experimentally, but also increases with increasing hydration as well.  The calculated normal mode density from CHARMM shows similar frequency dependence at low frequencies. However, a broad peak centered at 60 cm-1, which emerges with increasing hydrations, hasn’t been observed experimentally. The hydration dependence of the calculated absorption intensities are in approximate agreement with the measured THz absorbance, except at low hydrations and at low frequencies. The breakdown in agreement may be due to all waters, including crystal waters, being treated with the simplified TIP3 water force field.     

Title: Modeling of Kidney Functions
Dr. Saziye Bayram, Mathematics Department, Buffalo State College

A human kidney contains approximately one million nephrons, the basic functional unit that filters blood into urine. The functional state of a nephron in a normotensive rat is experimentally characterized as either steady or as limit-cycle oscillations (LCO). The oscillatory behaviors in nephrons’ flows are mediated by a negative feedback system known as tubuloglomerular feedback (TGF). Although the physiological significance of LCO still remains unclear, based on experiments it is suggested that LCO may act to enhances the sodium chloride excretion and thereby limit the degree of hypertension.

Many mathematical models of control exhibit oscillatory solutions; oscillations are also a feature of delay differential (or integral) equations. We present the modeling of nephrons with these mathematical tools and interpret the results analytically using bifurcation analysis and numerically by using computer simulations.

POSTER SESSION