RESEARCH PROGRAMS

Related Faculty: Bilgutay, Cohen, Genis, Goldberg, Herrmann, Lewin, Newhouse, Reid, Rorres, Shankar, Tretiak, Wheatley, Ziskin

Medical ultrasound refers to the use of high-frequency acoustic energy for the purpose of medical diagnosis, monitoring, therapy, and investigation. Today, medical ultrasound finds widespread use in cardiology, for the assessment of a valvular stenosis, myocardial motion, and, most recently, cardiac blood flow. The use of ultrasound in obstetrics has expanded to a point where now between one-third and one-half of all pregnant women in the United States receive one or more ultrasound examinations.

Many of the larger organ systems of the body can be effectively imaged with ultrasound, for the detection of cysts, tumors, calcifications, tissue abnormalities, and changes in size. The organs most commonly examined with ultrasound are the liver, kidney, pancreas, breast, and uterus. In recent years, ultrasound has also become a most valuable tool in ophthalmic examinations. Conditions such as detached retina, tumors of the eye, and bleeding and foreign bodies in the eye are easily detected.

Ultrasound is not only well established for diagnostic use, but has found extensive use in diathermy for deep tissue heating in situations such as arthritis, muscle injury and inflammation, and tendinitis. In the last few years another therapeutic application of ultrasound has been implemented clinically, in extracorporeal shock wave lithotripsy--a medical procedure using focused sound waves to fragment kidney and gallbladder stones, without the need for surgery.

Research Activities

• Ultrasound image processing
• Tissue characterization
• Modeling of ultrasonic bonders for quality monitoring
• Angular spectrum method to characterize propagation in inhomogeneous media
• Transducer materials and characterization
• Estimation of beam-flow angle from Doppler spectrum
• Flaw detection
• Ultrasonic bubble sizing and fluid pressure measurement
• Direct and inverse problems in lossy acoustic media
• Early diagnosis of breast cancer using Doppler/B-mode ultrasound
• Early detection of breast cancer by Time Delay Spectrometry ultrasound
• Noninvasive characterization of atherosclerotic plaques
• Flow measurements
• Nonlinear acoustics
• Bioeffects
• Physical aspects of lithotripsy
• Shock wave sensors for noninvasive kidney- and gallstone fragmentation
• Evaluation and development of ultrasound contrast agents

The faculty contact person for this program is Peter A. Lewin, Ph.D.

Related Faculty: Addison, Ferrone, Kalidindi, Ko, Laurencin, Wheatley

Activities in the biomaterials area at Drexel have been part of the Biomedical Engineering and Science Institute since its beginning. Recently biomaterials research has expanded to include fibrous materials and the various prosthetic devices requiring the use of both synthetic and natural fibers.The national trend is for emphasis on improved materials performance and design. Some of the new fields of investigation are micro tissue characterization and evaluation, macromolecular drug release, three-dimensional fiber-reinforced composites, and material surface modification.

Research Activities

• Controlled insulin delivery system
• Fiber-reinforced composites for bone fixation plates
• Composites for dental tooth-root implants
• Dental restorative composites
• Impedance measurements for tissue-implant biocompatibility
• Blood-biocompatible polymeric coatings
• Composite material damage assessment
• Corrosion detection in adhesively bonded structures
• Artificial ligaments
• Orthopedic cast
• Finger joint prosthesis

The faculty contact person for this program is Frank K. Ko, Ph.D.

Related Faculty: Esquenazi, Freedman, Kalidindi, Hillstrom, Ko, Lau, Laurencin, Seliktar Siegler

Biomechanics is a broad area encompassing all disciplines in which mechanical principles are applied to the understanding and acquisition of scientific knowledge relating to the function of the human body. It includes, for example, orthopedic biomechanics, in which this knowledge is applied to develop orthopedic devices such as endoprostheses, fracture fixation devices, and artificial ligaments, as well as to develop improved surgical procedures. Another branch of biomechanics is the development of aids for the handicapped, recently identified by NSF as an emerging area of national importance and expected to receive increased attention and federal funds in the near and long term. Rehabilitation engineering is another important branch of biomechanics.

Its major aim is to improve, through the application of engineering principles, the rehabilitation process of the handicapped individual.

An important emphasis of the activity in biomechanics is that research must be highly relevant to the clinical community. This is reflected in the close ties established between the program and major hospitals, medical schools, and health care industries in the area.

Research Activities

• The stabilizing role of human ankle and subtalar ligaments
• The effect of Achilles tendon lengthening on the passive and active properties of the human
• ankle joint
• Investigation of the optimal load bearing characteristics of the patellar tendon in P.T.B.
• prostheses
• Application of inverse optimization methods for the identification of the governing principle
• of voluntary human arm motion coordination
• Development of a control strategy for whole arm prostheses and robotic manipulators

The faculty contact person for this program is Rami Seliktar, Ph.D.

Related Faculty: Dubin, Hrebien, Jaron, Johansen, Marks, Santamore, Zietz

Studies of the cardiovascular system and its diseases have historically been a significant part of the research effort of the Biomedical Engineering and Science Institute. A prime reason for this interest is the great benefit that progress in this research area can provide to the quality of life of individuals and to our national economy. At present, it is estimated that more than 35 million Americans suffer from some type of cardiovascular disease. Over one-half of all deaths in the United States are attributable to cardiovascular problems, and over 20 percent of those deaths occur before age 65, during the most productive life period. In 1979, it was estimated that cardiovascular mortality, and the loss of production due to this type of illness, cost the nation's economy $81.3 billion.

Although cardiovascular research attracts many investigators, the Biomedical Engineering and Science Institute possesses several advantageous features found in few other research centers. Since its inception, the Institute has used a balanced (engineering and medical) approach in its research. The program's interdisciplinary nature makes it possible to bring a wide spectrum of interests and expertise to bear on research problems. This is especially appropriate for cardiovascular research, where many branches of engineering and life sciences must be employed to provide practical solutions to problems. The interdisciplinary nature of the program also attracts a wide range of students. The mix of students with backgrounds in life sciences, engineering, and clinical and allied health professions provides a synergism not found in traditional engineering or medical programs.

In addition, the proximity of Drexel to the fine medical schools, hospitals, and biomedically related industry of the area provides great opportunities for collaboration.

Research Activities

• Modeling of the cardiovascular system
• Cardiovascular dynamics
• Cardiovascular instrumentation
• Noninvasive evaluation of cephalic blood flow in the high-G environment
• Use of external pulsations to increase tolerance to acceleration stress
• Control of cardiac assistance devices
• Innovative techniques for noninvasive continuous blood pressure monitoring
• Coronary circulation
• Assessment of cardiac function

The faculty contact person for this program is Dov Jaron, Ph.D.

Related Faculty: Dubin, Hrebien, Jaron, Johansen, Marks, Santamore, Zietz

This field deals with the production and automatic interpretation of images that arise in medicine and in biomedical research. Medical imaging techniques include computed tomography, nuclear magnetic resonance imaging, and real-time ultrasonography. Devices for the automatic karyotyping of human chromosomes are an example of clinical application of machine interpretation . Among the diverse research applications are isotope tracer and fluorescent labeling techniques that are vital in the study of the structure and function of living organisms.

The Biomedical Engineering and Science Institute has established a track record in general image processing and in diagnostic ultrasound. A Biomedical Technology Center in autoradiographic image processing, funded by NIH, was established here in 1984. The increasing role of medical care in the national economy, coupled with federal recognition of the importance of biological imaging, implies that research and development in the field will continue to expand.

Research Activities

• Autoradiography
• Quantitative analysis of shape applied to visual images
• Signal processing schemes for target extraction and automatic clutter rejection in radar
• Inverse acoustical scattering
• Model-based image analysis of medical images
• Center for Biomedical Imaging

The faculty contact person for this program is Jonathan Nissanov, Ph.D.

Related Faculty: Dubin, Herrmann, Zietz

Although there has been much technological advancement in medical care, a major limitation has been in the delivery of its benefits to the public in an expeditious and economical manner. A large portion of the high-tech aspect of health care delivery takes place in the hospital, an environment conducive to high cost, tedium, contagion, and--unless its special facilities are needed--inefficiency. Before the tendency to centralization of health care delivery, the care of a child with an acute sore throat and fever usually involved a prompt, comforting visit, at home, by the family doctor, at a cost of a few dollars. Today the same problem might be met by a visit to a hospital emergency room in a milieu of noise (even physical violence), treatment by persons unfamiliar to the family, delay, confusion, and outrageous expense. More recently there has been a trend toward returning medical care to the home. There is, however, a great deficit in our ability to provide diagnostic, therapeutic, and educational health services in a decentralized setting. The ability to provide definitive health care in the home will mean great savings in terms of safety and convenience, as well as in time and expense.

Among the particular criteria for health care delivery in the noncentralized environment are noninvasiveness, and simplicity and objectiveness of operation, in addition to the conventional requirements of safety and effectiveness. Other important issues include the ethical, legal, financial, social, and educational aspects of such technology transfer. These considerations impose the need for intensive multidisciplinary study in addition to engineering innovation.We are currently utilizing modern computer technology to address the above concerns in some specific areas.

Research Activities

• Deamination burden as a parameter of diet planning
• Computer-aided diet planning
• Microcomputer support of home health care
• Center for Computing in Health Care
• Biostatistics
• Methodology/Epidemiology
• Expert/Advisory systems for statistical consulting
• Technical and quantitative support of laboratory animal resources
• System validation for the pharmaceutical industry

The faculty contact person for this program is Stephen Dubin, Ph.D.

Related Faculty: Dubin, Eisenstein, El-Sherif Jaron, Onaral, Sun

The research in biomedical signal processing includes several areas of current interest in the biomedical field aimed at the extraction of features for pattern recognition and noise reduction. Various techniques from estimation and detection theories are used to reduce noise and to producebetter wave forms. Principles and techniques of digital signal processing, communications, and pattern recognition are applied to the acquisition, storage, and analysis of biological signals, with emphasis on electroencephalograms and electrocardiograms. One of the main focuses of our research is data reduction techniques coupled with methods of directly processing the compressed signals without loss of clinical information. Another important application of signal processing is in understanding of the basic mechanisms of pathophysiological events generated by signals. For example, efforts are underway to quantitate cardiac late-potentials in order to identify patients prone to life-threatening cardiac arrhythmias.

Research Activities

• Methods for detection of high-G blackout by digital signal processing of the EEG
• Database reduction and processing techniques for electrical activity maps of the brain
• Advanced signal processing of gastrointestinal signals
• Automatic compensation for the distortion in clinical blood-pressure measurements
• Interpretive Holter ECG analysis and data compression for digital storage
• Detection of life-threatening cardiac arrhythmias using time-frequency analysis of
• ventricular complexes
• Analysis of exercise stress ECG
• Source localization in neuromagnetometry and evoked potentials

Related Faculty: Freedman, Guez, Nabet, Rybak

The area of neural systems encompasses those research activities dealing with sensory and motor aspects of living organisms. Research may involve modeling of neurophysiological and neuropsychological phenomena or the application of the knowledge of living neural systems to nonliving devices such as robots or computers (neural networks).

The emphasis of the biomedical engineering neural systems program is on the control of biological processes. Current projects include determining the interaction of the cervico-ocular reflex and the vestibulo-ocular reflex in their effects on posture and locomotion; modeling the attentional control of behavior and learning; implementing mixed rule base and neural network architectures using object-oriented style programming; the effect of norepinephrine depletion on the relearning of motor tasks; and models of automaticity.

Research Activities

• Biomechanical and EMG correlates of step-down in humans
• The effect of norepinephrine depletion on the relearning of motor tasks
• Cervico-ocular reflex and vestibulo-ocular reflex effects on eye stability during passive
• movements
• Neural network description of plasticity in motor systems
• Modeling attentional control of behavior with a hierarchal neural network (HNN)
• Implementing mixed rule base and neural network architectures using object-oriented style
• programming
• Modeling attentional control of learning with a hierarchal neural network
• Models of automaticity
• Neural networks in signal processing
• Cognitive psychophysiology correlates from evoked magnetic fields and evoked potentials
• Neural network processing of evoked magnetic fields and evoked potentials
• Computational modeling of neural mechanisms for control of respiration and locomotion

The faculty contact person for this program is Allon Guez, Ph.D.

Related Faculty: Ferrone, Finegold,

Biophysics is a branch of physics concerned with living organisms. The goal of biophysics is to explain biological events in terms of physical laws and principles. Biophysics uses the tools and concepts of the physicist and mathematician to define and approach biomedical problems.

Research Activities

• Dynamics of biomolecules
• Laser-induced temperature jumps in single muscle fibers
• Laser photolysis of caged compounds
• Study of muscle cross-bridge kinetics using synchrotron radiation
• Phase Transitions in Biomembranes

The faculty contact person for this program is Frank Ferrone, Ph.D.

Related Faculty: Dellavecchia, Dubin, El-Sherif, Nabet

The research in sensory systems is related to the principles and techniques of biomedical engineering in a number of ways. First, electronic information processing and optical procedures may be developed and employed to evaluate normal sensory function, as well as the diagnosis of pathologies involving sensory systems. Second, biomedical engineering is intimately involved in the development of assist devices which may be employed when sensory function is impaired by disease or genetic defects, as well as in normal losses of sensory function which accompany aging. Third, the techniques of biomedical engineering may be employed to evaluate the effects of environmental stress on sensory function, such as those encountered in the military, e.g. the effects of G forces on sensory function. In addition to these numerous and more obvious applications of xbiomedical engineering, sensory receptor systems have achieved remarkable sensitivity, dynamic range, and temporal and spatial resolution. An interesting example of the evolutionary development is the ability of the dark-adapted rod photoreceptor to function as a single photon detector. An understanding of the principles by which sensory systems detect and process information may lead to the application of such principles to the development of man-made detectors and information processing devices. In this case the role of biomedical engineering would be that of mimicking nature in its extraordinary capacity to detect and process information about its environment.

Research Activities

• Mechanisms of retinal blood flow regulations
• Coupling of oxidative metabolism to function in vertebrate photoreceptors
• Roles of retinal arrestin in signal transducing systems

The faculty contact person for this program is Bahram Nabet, Ph.D.

Related Faculty: Cohen, Nissanov, Tretiak

in-progress

The faculty contact person for this program is Jonathan Nissanov, Ph.D.

Related Faculty: Wheatley,

Many drugs, such as vaccines, hormones and some antibiotics, require a delivery regime which is not zero order, for example vaccines need to be administered in pulses with time intervals between the pulses varying from a few weeks to months, while the hormone insulin needs to be delivered in response to elevated blood glucose levels. We approached this problem by combining two established technologies, liposomal entrapment of drug, and microencapsulation, to develop an entirely new modality, microencapsulated liposomes. This allows us two control points. No drug will be delivered until it is first released from the liposome, and once it is released the rate at which it is delivered to the body can be controlled by a rate controlling membrane on the microcapsule. The system also offers the advantage that the liposomes are protected from the immune system, and therefore are not taken up and delivered to the liver and spleen, and are also protected from phospholipid exchange that could occur if they were in the blood stream.

Liposomes are self assembling vesicles, in the nanometer to micron size range, composed of a bilayer of phospholipid molecules. The size and structure are determined by the method of preparation. When the liposomes form they entrap a portion of the aqueous environment, and if a drug, such as insulin, is dissolved in that aqueous medium then that will become entrapped.

We have chosen to make microcapsules by ionotropic gelation of the naturally occurring polymer, alginate. When an aqueous solution of sodium alginate is sprayed into calcium chloride solution, the drops gel upon contact with the calcium ions in the solution. If drug-containing liposomes are suspended in the sodium alginate before spraying, then they will become encapsulated. A rate-controlling membrane of a polycation such as poly-L-lysine can be coated on the microcapsules by simple contact with a polymer solution. This aqueous, mild microencapsulation method is ideal for encapsulation of sensitive structures such as liposomes. The size of the capsules can be controlled form about 50 µm to over 500 µm by the method of spraying.

As liposomes age they become leaky. We have developed a system of encapsulated liposomes, which will release their contents at different time points, depending on the composition and type of liposome. In this way, if a cocktail of liposomes is encapsulated, drug could be released in a series of pulses.

Management of diabetes requires delivery of exogenous insulin, preferably in response to elevated blood glucose levels. In the literature, we have found an amphipathic polymer, polyethyl acrylic acid (PEAA) that has been developed by Dr. D. Tirrell at the University of Massachusetts, which changes conformation and hydrophobicity with pH. At low pH the polymer adopts a globular hydrophobic conformation which interacts with the liposome bilayer causing it to become leaky. We have shown that the rate and extent of leakage can be controlled by the pH and the liposome to PEAA ratio. We are developing a responsive capsule which will contain liposomes loaded with insulin, PEAA and immobilized glucose oxidase enzyme(GOD). The scenario which we envision is that glucose will diffuse into the capsule, react at the GOD, the resulting gluconic acid will lower the pH, the PEAA will become protonated, change conformation and disrupt the bilayer, insulin will be released, pass out of the capsule, lower the glucose levels, the pH will re-equilibrate with the physiological pH of 7.4 and the leakage of insulin will cease.

Depending on the temperature, phospholipids in a membrane can be in either a gel or crystalline phase. The temperature at which they pass form one phase to another is called the phase, or glass transition temperature (Tm). Different phospholipids have different phase transition temperatures, and liposomes become leaky as they pass through the transition temperature of their constituent liposomes. We are investigating the use of temperature to induce leakage in encapsulated liposomes as a method of drug delivery to areas of elevated temperature such as tumors, inflammation and infection.

Research Activities

• Development of pulsed and triggered release systems
  • Liposomes
  • Microcapsules
• Pulsed system for vaccines
• Triggered system for Insulin delivery
• Temperature sensitive liposomes for pulsed release

The faculty contact person for this program is Margaret Wheatley, Ph.D.

Research Facilities and Environment

Biomedical Engineering Laboratory

The biomedical engineering laboratory is set up for research into controlled-release of drugs, and for development of a novel ultrasound contrast agent. In addition to standard laboratory equipment such as pH meters, rotary evaporator, bench centrifuge and analytical balances, this facility includes a controlled environment incubator, Heat Systems probe sonicator, Laboratory supplies bath sonicator, custom built ionotropic gelation apparatus, Packard scintillation counter, and a Hitachi U2000 UV/visible scanning spectrometer with variable temperature cells and accompanying computer for data acquisition and analysis.

Biomaterials Laboratory

Biomaterials research has recently expanded to include fibrous materials and various prosthetic devices requiring the use of both synthetic and natural fibers. The trend is toward the emphasis on improved materials and design. Some of the new fields of investigation are the micro tissue characterization and evaluation, macromolecular drug release, three dimensional fiber-reinforced composites, and material surface modification. The Biomaterials Laboratory facilities include diffusion cells for drug release measurements, a polymerization facility, a thermal analysis facility for polymer characterization, scanning and transmission electron microscopes, RF plasma reactor. Laboratory extruder, two-ounce injection molding machine, hot press, rubber mill, x-ray facility, and centrifugal casting machine.

Signal Processing Laboratory (SPL)

The Signal Processing Laboratory (SPL) facility features networked computer-based data acquisition, instrument automation and graphics capability and incorporates a Sun SPARC 20, a number of personal computers, and an HP 3562A Dynamic Signal Analyzer, a EG&G PAR 173 Potentiostat/Galvanostat. Other general purpose laboratory equipment includes scopes, multimeters, pulse and signal generators, power supplies and amplifiers.

Scaling Signals and Systems Laboratory (SSSL)

The Scaling Signals and Systems Laboratory (SSSL) is a facility dedicated to the measurement, analysis, and modeling of broadband distributed phenomena which 'scale', i.e., exhibit systematic relationships between temporal and spatial scales. Research projects in biomedical signal processing and system analysis exploit advanced methods of multi-scale system theory as well as multi-rate and multi-resolution signal processing techniques.

Ultrasound Laboratories

The Ultrasound Laboratories researchers use high frequency acoustic energy for the purpose of medical diagnosis, monitoring, therapy and investigation. Medical ultrasound is widely used in cardiography and obstetrics but is also used in many other areas as well. the organs most commonly examined with ultrasound are the liver, kidney pancreas, breast and uterus. Recently, ultrasound has also become a most valuable tool in ophthalmic examinations easily detecting conditions such as detached retina, tumors of the eye, and bleeding.

Communications and Signal Processing Laboratory (CSPL)

The Communications and Signal Processing Laboratory located in Commonwealth Hall, Room 707 is dedicated to research in statistical signal processing.

Some of the current projects are:

1. communications (blind equalization);
2. higher-order spectra analysis (system identification, signal reconstruction, low-rank estimators of higher-order statistics;
3. alpha-stable processes and relationship with 1/f signals;
4. ultrasound imaging (resolution improvement of ultrasound image for breast cancer detection at early stages, attenuation estimation);
5. earthquake engineering (site response analysis).

The lab currently serves 8 graduate students, and is established through funding from the National Science Foundation, US Army, The Whitaker Foundation, and support from Drexel University.

The lab is equipped with:

• SUN Ultra ENTERPRISE 2, Dual-200 MHz processors, 8.6 GB Hard Disk, 256 MB R AM, Exabyte 8505/XL Tape Drive (6-14 GB), CD-ROM (internal), Floppy Disk (1.4 MB internal), color monitor, Solaris 2.5.1.
• SUN Ultra 1, 147 MHz Processor, 2 GB Hard Disk Space, 64 MB RAM, color monitor, Solaris 2.5.1.
• SUN SparcStation 5, 110 MHz processor, 64 MB RAM, 1.2 GB Hard Disk, CD-ROM (external), color monitor, Solaris 2.5.
• SUN SparcStation 5, 70 MHz processor, 64 MB RAM, 2.4 GB Hard Disk, color monitor, Solaris 2.5.
• Three (3) HDS @work Supra-66 17CH X-terminals, color monitor, 16 MB RAM.
• APPLE LaserWriter 16/600 PS

Imaging and Computer Vision Center (ICVC)

The Imaging and Computer Vision Center is located in Commonwealth Hall, Room 110. ICVC pursues research in the fields of imaging, computer vision, image processing, image pattern recognition, and the extraction of quantitative data from images. Work is performed in a number of application domains, with concentration on Biology and Medicine.

Laboratory: The Imaging and Computer Vision Center consists of both a computer (about 1800 sq. feet) and an histology laboratory (about 250 sq. feet). The computer laboratory is equipped with UNIX and Macintosh platforms. The UNIX computers are: Silicon Graphics (4D220 and Personal Iris), SUN (4/260 and 4/110), and PC compatibles. These computers are interconnected through Ethernet to the campus network and INTERNET. The Macintosh computers are connected through AppelTalk to a server and a bridge to Ethernet and INTERNET. Peripheral equipment includes television cameras for image capture, color and monochrome displays, document scanners (an Agfa Arcus 1200 DPI and an Apple 4-bit scanner) and laser printers. Among other software, the lab has operating systems and languages for program development, programs developed in house, commercial image processing, display, graphics and word processing applications.

The histology laboratory currently has a custom-designed Leica Jung Cryopolycut cryostat with mounted digital camera, a Hacker-Bright cryostat fitted with a Instrumedics tape support system, a vibratome, 2 dissecting scopes (an Olympus and an upright surgical Zeiss), 2 Zeiss microscopes including an Axoplan, and the various small items necessary for histological processing.

Calhoun Laboratory for Comparative Medical Science

The Calhoun Laboratory for Comparative Medical Science is Drexel's central facility for the care and use of warm blooded laboratory animals. It occupies about 7000 sq. ft. in the modern Lebow Engineering Center. Facilities are available for sterile surgery, radiography, and other research procedures. Research laboratory space is provided to facilitate those projects where investigators require rapid access to animals, their tissues or fluids.

Small Animal Chronobiology Laboratory

The Small Animal Chronobiology Laboratory is part of the Calhoun facility and features environmental chambers capable of housing rodents in controlled conditions. These chambers are sound-attenuated with individual computer-controlled temperature and lighting. Computerized data acquisition from running wheel activity using Nalge activity cages is possible 24 hours per day for up to 1 year. In addition to these chambers, HEPA filtered isolation units with controlled lighting for immunological experiments with mice or hamsters are also available.

Biomechanics Laboratory(BSL)

The Biomechanics Laboratory is equipped with anatomical dissection facilities; kinematic data acquisition systems; instrumentation for measuring joint flexibility, equipment for measuring acceleration, force and pressure. The Occupational Biomechanics Laboratory is where biomechanical, ergonomic and human factor aspects are studied with relation to injuries sustained in the work environment. The laboratory has close ties with the Human Motion Analysis Laboratory at Moss Rehabilitation Hospital. The Rehabilitation Engineering Laboratory is concerned with the development of equipment needed in the our research in the area of rehabilitation and aiding the handicapped. The laboratory has a children's mobility trainer, computer interfaced prosthetic arm, a variety of instruments for interfacial stress measurements in lower limb prostheses and other universal force displacement measuring systems. Research is going on in the following areas: limb prostheses, orthopedics implants, mobility aids for handicapped children; augmentative communication systems and other environmental control devices. Joint projects with the Rehabilitation Robotics Laboratory at the A.I. duPont Institute in Delaware are in progress. The research performed in the area of biomechanics is highly relevant to the clinical community and therefore requires close ties between the university and major hospitals, medical schools and health care industries.