Fred J. Looft

An Information-Theoretic Analysis of Cutaneous Receptor Responses

Two prevalent underlying assumptions related to cutaneous receptor research are that receptor responses are conditionally independent given the stimulus, and that stimulus information is encoded through a mean rate code. In this paper, an information-theoretic technique that can be used to test these assumptions is developed and presented. Results are presented from experiments designed to evaluate the efficiency of mean rate codes and the independence of receptor discharges recorded from cutaneous receptor afferent neurons.

The NASA Space Shuttle???A Vehicle for University/ Industry Educational Interaction

In December of 1982 Worcester Polytechnic Institute, with the cooperation and support of the MITRE Corporation, initiated a program to propose, select, design, and develop experiments to be flown onboard a NASA Space Shuttle. The educational objectives of this program, based on the experiences of the students, and the cooperative objectives based on the experiences of the faculty and staff of the two institutions, are presented. All of the proposed experiments are being developed by undergraduates with the advisorship of WPI faculty. MITRE engineers and scientists are supporting the projects through detailed development advice, design reviews, and program management advice. Overall, the program will require four years of effort, involving between 30 and 50 students and approximately a dozen WPI faculty and MITRE professional staff each year. The administrative structure designed to coordinate this program, the logistics of interactions between WPI, MITRE, and NASA, and the program schedule are presented in detail.

Integrating Systems Engineering and Systems Thinking into Undergraduate Engineering Education

This panel will discuss the challenges of Integrating Systems Engineering Knowledge and Skills in Undergraduate Education, considering why we do this, what we include and examples of how we do it. The panel is based on work done by the INCOSE Academic Forum.

A multivariate logistical model for identifying the compressive sensitivity of single rat tactile receptors as nanobiosensors

Tactile sensation is a complex manifestation of mechanical stimuli applied to the skin. At the most fundamental level of the somatosensory system is the cutaneous mechanoreceptor. The objective here was to establish a framework for modeling afferent mechanoreceptor behavior as a nanoscale biosensor under dynamic compressive loads using multivariate regression techniques. A multivariate logistical model was chosen because the system contains continuous input variables and a singular binary-output variable corresponding to the nerve action potential. Subsequently, this method was used to quantify the sensitivity of ten rapidly adapting afferents from rat hairy skin due to the stimulus metrics of compressive stress, strain, their respective time derivatives, and interactions. In vitro experiments involving compressive stimulation of isolated afferents using pseudorandom and nonrepeating noise sequences were completed. An analysis of the data was performed using multivariate logistical regression producing odds ratios (ORs) as a metric associated with mechanotransduction. It was determined that cutaneous mechanoreceptors are preferentially sensitive to stress (mean OR(max) = 26.10), stress rate (mean OR(max) = 15.03), strain (mean OR(max) = 12.01), and strain rate (mean OR(max) = 7.29) typically occurring within 7.3 ms of the nerve response. As a novel approach to receptor characterization, this analytical framework was validated for the multiple-input, binary-output neural system.

A Comparison of spectral transfer characteristics and tuning curves for monkey glabrous skin mechanoreceptors

Spectral transfer characteristics were determined for Slowly Adapting (SA, Merkel Cell), Rapidly Adapting (RA, Meissner) and Pacinian Corpuscle (PC) mechanoreceptors found in the glabrous skin of monkeys. Transfer function estimates were averaged and compared to the more traditional threshold and entrainment tuning curves for these receptors.

The evolution of the WPI Advance Space Design Program-an evolving program of technical and social analysis using the NASA Space Shuttle for engineering education

In December of 1982, Worcester Polytechnic Institute, with the cooperation and support of the Mitre Corporation, initiated a primarily undergraduate educational program to develop experiments to be flown onboard a NASA Space Shuttle. Christened the MITRE WPI Space Shuttle Program, it sponsored the development of five educationally meritorious experiments over a period of four years. Although the experiments were ready to fly in early 1986, the Challenger disaster delayed their flight until the Spring of 1991. The delay notwithstanding, the benefits of the first program were sufficient to justify the development of a second set of experiments. More comprehensive in scope, this new venture, named the Advanced Space Design Program, addresses both technical and social areas of interested related to space flight. The authors present a general historical overview and self-assessment of WPIs space design programs. >

Spatial frequency tuning in cutaneous type I receptors

The encoder characteristics of cat, hairy skin, slowly adapting Type I (T1) receptors were studied by activating them with swept period grating stimuli drawn over the skins surface. It was hypothesized that the puncate organization of these receptors and the possibility of action potentials from one dome blocking the responses from other domes would result in a receptor behaving as a matched filter to specific periods of a grating stimulus. Laboratory experiment and preliminary numerical modeling results of receptor responses that support the matched-filter hypothesis are presented.<<ETX>>