Copyright © 1996 by the Biomedical Engineering Society
We have entered an exceptional time for biomedical engineering. Amazingly rapid advances in cell and molecular biology have opened the possibility of a whole new generation of therapeutic products, including the use of cell-based systems. Coupled to this information explosion in the biosciences is the continued development of more versatile and more powerful computational systems, allowing new horizons in imaging, data analysis, pattern recognition and control algorithms. Biomedical engineering sits at the interface between these scientific advances and their applications in the clinical environment. This is a tremendously exciting place to be, and one manifestation of the excitement is the nation-wide expanding interest in biomedical engineering as an undergraduate major. Developing a coherent educational program that incorporates the new biological science, much of it at the molecular or nano scale, with the traditional integrative or systems approach of engineering is a major challenge for our profession. It also is a unique opportunity that we must take advantage of since the potential applications, leading to improved quality of life for patients, are limited only by one's imagination. This new kind of biomedical engineering program must also prepare our students to be aware of the ethical implications of their work (for instance, handling and using individual patient data from the analysis of gene sequences and the possible relation to disease processes), to be able to work in an environment of increasing pressure to contain the cost of health care while not stifling progress and creativity, and to be active participants in the public policy and regulatory debates that will crucially influence the health of our profession.
At Rice, we have begun the process of trying to put together such an undergraduate program. Many (probably soon to be most) major universities have also started along similar paths, with the goal of combining in a productive way modern biological science with engineering. Each university will have a different solution, sometimes involving a formal biomedical engineering departmental structure and sometimes integrating biology directly with classical engineering departments. The excitement of the students is amazing. For example, at Duke University there are 125 entering freshman in their Biomedical Engineering Program - more than the rest of engineering. Not only are the numbers high, but the quality of these freshmen biomedical engineers is also outstanding. We in academia have a responsibility to these students to provide the best biomedical engineering education possible, but also to be honest with them about future job possibilities. Most graduates will need to have a broad background that will allow them to continue their education throughout life - often as they also evolve through several different professional positions. Our programs will be judged by how well prepared biomedical engineering graduates are to succeed and prosper in the 21st century. The challenges for Biomedical Engineering Education are impressive - but as a university professor I can think of nowhere else I would rather be. A text that attempts to capture many of the different aspects of both the potential and the challenges has recently been published by a new branch of the National Academy of Sciences Press. It is the edited proceedings of a three-day conference held at Rice University in 1994, and is entitled Biotechnology: Science, Engineering and Ethical Challenges for the 21st Century (F.B. Rudolph and L.V. McIntire, editors), Joseph Henry Press, Washington, DC (1996).
The Biomedical Engineering Society (BMES) has established its home page on the World Wide Web at the following address: http://mecca.mecca.org/BME/BMES/society/bmeshm.html (case-sensitive). From this site one can obtain information regarding all activities of the Society, including updates on forthcoming meetings, e-mail addresses, membership applications, and access to the Web pages of the BMES Bulletin and Annals of Biomedical Engineering. Many thanks to Rita Schaffer, BMES Executive Director, and Jack Buchanan, Professor of Biomedical Engineering and Director of MECCA (Memphis Educational Computer Connectivity Alliance), for agreeing to support this endeavor. Also, the efforts of Qiuying Huang and Steve Charlebois, the individuals directly responsible for the construction and maintenance of this page, both of whom are graduate students at the University of Memphis and the University of Tennessee, Memphis, are gratefully appreciated. Please visit our Web site; comments and suggestions regarding content and format are always welcome.
Congratulations to all of the student chapters of the BMES who submitted an annual report for review. The hard work and dedication to the Society are apparent from your reports and you all deserve a pat on the back for your accomplishments. A special congratulations to all of the officers of these groups. I know your hard work helps to keep the BMES chapters functioning at such a professional level.
This year, nine chapters submitted reports, which were reviewed by a committee of three individuals from three separate institutions. At this time, I would like to thank these three judges for their time. Of the nine reports, four chapters were chosen to receive a plaque at the Annual Fall BMES meeting at Penn State and three chapters received a certificate. The plaque winners (in alphabetical order) are: Arizona State University, Louisiana Tech University, The University of Akron, and The University of Virginia. The certificate winners are: Marquette University, The University of Alabama at Birmingham, and The University of Florida.
I would like to encourage all student chapters to submit reports for next year's competition. If you have any questions regarding what is required or expected, please do not hesitate to contact me. The report is a great way to highlight the many things you are doing and provides a nice way of reviewing what previous groups at your own university have done.
I would like to take this opportunity to mention some of the activities that these winning chapters have been active in over the past year and to encourage you all to adopt those activities which interest you and your fellow students. I firmly believe that the more people you get involved in the planning and organizing of activities, the easier it is to get things done. No one person, president or not, has the time in their busy academic schedules to get much done. DELEGATE, DELEGATE, DELEGATE. Committees seem to ease the work load and distribute the power and fun to more individuals. Therefore, I will list suggested activities under potential committee headings:
(1) Job Search/Industrial Relations. Activities can include holding
interviewing and resume workshops, building a database of BME companies,
organizing a job board, creating a resume book and engaging speakers on
searching for a job.
(2) Tours/Speakers. Trips to local BME industry and tours of
hospitals and other medical facilities inform your members about potential
employment opportunities, as well as informing the local medical community
about your university and student BMES section. Speakers can be recruited
from within or without, faculty or students, technical or non-technical
-- whatever interests your members.
(3) Newsletter/Media. Generate a BMES newsletter, a departmental
video, a student homepage on the Internet or a recipe book. Let the world
know what you are doing and write an article for the BMES Bulletin. This
really counts big for the annual report. You can never get enough experience
writing, both technical and casual.
(4) Social. This is most important as it keeps everyone working
and playing together in a collegial manner. Try picnics, tailgate parties,
camping, Halloween parties (definitely a costume party), canoe trips, happy
hours, etc. Don't forget to invite the faculty and staff - they like to
party too.
(5) Sports/Intramurals. Enter intramural teams in whatever sport
you like, have volleyball games, golf tournaments and flag football (try
faculty vs. students).
(6) High School Outreach. Many groups have developed outreach
programs to inform high school students about BME. This is probably more
attractive to groups with undergraduate degrees in BME, but participation
in general engineering recruitment is fun and sooner or later they will
also be considering graduate school.
(7) Fund Raising. Always a necessary evil, and not always a
lot of fun, fund raising activities can be as creative as you can imagine.
Try the ever-popular T-shirts or coffee mug sales, car washes, raffles
or auctions. Check with your student development office for more ideas
and let me know if you come up with some original ideas to share.
(8) Service. Many chapters also developed volunteer and service
activities to assist other students and their community. This included
participation in blood drives, can food drives, adopting a family at Thanksgiving
or Christmas, recycling, tutoring at the high schools and grade schools,
Habitat for Humanity and hospital volunteering.
(9) Welcome. It is always nice to be welcomed to a new place
by some seasoned students who know the ropes. Try a new student handbook
or a welcoming social to let the new students meet the old.
The above suggestions are only a handful of ideas. I hope that everyone finds something new to try this year. It's great to continue on past successes, but much more fun to develop new ones as well. Look to your members for ideas, hand out a survey to determine their interests and past experiences. The key is to get everyone involved.
One last item: several groups have contacted me about moving the award competition to encompass an academic year as opposed to the calendar year. The reports would cover the school year, from August to July and not from January to December. Most other student organizations operate this way. I would like to know how you all feel about this proposed change. Please e-mail me with your ideas and anything else that is on your mind. I'm here for you, the students.
Dr. Mary C. Verstraete
BMES Student Affairs Committee
Department of Biomedical Engineering
The University of Akron Akron, OH 44325-0302
(330) 972-7691
mary@brain.biomed.uakron.edu
Introduction
Acrylic bone cement is one of the most widely used materials in contemporary orthopaedics. It is currently the only material used for fixation of endoprostheses to the contiguous bones in cemented arthroplasties. In this application, the primary functions of the cement are to transfer body weight and service loads from the prosthesis to the bone and/or increase the load-carrying capacity of the prosthesis-bone cement-bone system.
Bone cement has many attractive features. It allows fixation of the implant, usually within 30 minutes. It intrudes extensively into the interstices of the bone, allowing excellent initial anchorage of the prosthesis. It is surgically forgiving and can easily be removed prior to revision arthroplasty.
On the other hand, bone cement has a number of drawbacks. It contributes to thermal and/or chemical necrosis of the bone. It predisposes to membrane formation at the cement-bone interface. It shrinks during polymerization. There is a large stiffness mismatch between the cement and the contiguous bone. The cement mantle, the implant-cement interface and the cement-bone interface are three "weak-line zones" in the construct (1). It is not firmly established at this time whether any of these features contributes to the initiation or is the consequence of aseptic loosening. The current consensus is that mechanical failure of the cement at any or all of the weak-link zones is the cause.
The survival probabilities of recently-implanted cemented arthroplasties in patients aged over 50 years, especially those of the hip and knee, have been very high. They average at least 90% after 15 years (2, 3). Improvements in cementing techniques and implantation methods have contributed to this success. In spite of this record, the use of bone cement has always been viewed with a certain amount of ambivalence. There have been and continue to be attempts to dispense with its use altogether. To date, however, the clinical outcomes of cementless total hip and knee arthroplasties have been well below expectation (4, 5). A new set of problems has been spawned by their use. For example, in hip implants, perioprosthetic osteolysis, high thigh pain and failure of the bone-implant interface have been widely reported (6).
Interest in the use of bone cement continues, with three main areas of focus: development of methods of preparation of the current commercial formulations of cement which can easily be used in the operating room setting and which lead to improvements in physical, chemical and mechanical properties; improvement of techniques for delivering the cement dough to the intramedullary canal just prior to prosthesis placement; and synthesis of new formulations, based on polymers other than poly(methyl methacrylate), PMMA, the most commonly used polymer.
In the United States there are six commercial formulations in popular use: Simplex P (Howmedica, Inc., Rutherford, NJ); Zimmer Regular¨ and Zimmer Low Viscosity Cement, LVC¨ (Zimmer, Inc., Warsaw, IN); Palacos¨ (Smith & Nephew Orthopaedics, Memphis, TN); and CMW-1 and CMW-3 (Wright Medical Technology, Arlington, TN).
The following review begins with brief descriptions of mixing methods of the popular commercial formulations of bone cement and is followed by a summary of the results of studies of mixing methods and their effects on cement properties. A critical examination of these results is then used to identify research directions.
Mixing Methods
Mixing methods include hand mixing, centrifugation, vacuum mixing and combined mechanical mixing. In hand mixing, the powder component is added to the liquid (which may or may not have been chilled to a temperature usually between -15 oC and 4 oC) in a polymeric, usually polypropylene (PP), bowl. Then these components are stirred, using a PP spatula, at 1 Hz (7) or 2 Hz (8) for a period of time between 45 s (9) and 120 s (10).
In centrifugation mixing, the hand-mixed dough is immediately poured into a syringe from which the nozzle had been detached. The syringe is then promptly placed in a centrifuge and spun at a maximum speed of between 2,300 rpm (11) and 4,000 rpm (8) for a time between 30 s (11) and 180 s (12).
A number of proprietary and experimental chambers have been used for vacuum mixing. The proprietary ones include: the Simplex Enhancement Mixer (Howmedica, Rutherford, NJ), Stryker High Vacuum System (Stryker, Kalamazoo, MI), MITAB (Mitab, Corp., Sjobo, Sweden), Optivac (Mitab), Stryker Mixevac II (Stryker), and Sterivac (SD, Germany). There are no generic steps in vacuum-mixing , as is the case in hand or centrifugation mixing. Outlines of the steps used in two of these chambers are presented below.
When the MITAB¨ vacuum chamber (13, 14) is used, the powder is added to the liquid in a mixing box which is then placed in the chamber. The chamber is then closed and a vacuum of 28 kPa (absolute) is applied, while the cement constituents are being manually mixed with a PP spatula at 0.25 Hz for between 30 and 75 s. Then the box is removed from the chamber, and a lid with an attached nozzle is applied to the chamber. The cement is collected at the top of the nozzle, at atmospheric pressure, by a cement gun.
When the Simplex Enhancement Mixer (15) is used, the powder is added to the liquid in the mixing chamber. The mixture is then stirred manually with a special spatula until the powder is saturated. A vacuum of 15 kPa (absolute) is drawn into the chamber, while stirring at 1 Hz continues for 90 s.
One experimental vacuum mixing system was used by Scheurs et al. (16). In this system, the powder is placed in a syringe, the liquid is poured into a glass bowl, and a vacuum of 29 kPa (absolute) is applied. The glass bowl is rotated to pour the liquid into the powder. Stirring of the mixture with the aid of a rotor at 200 rpm then proceeds for 45 s, after which the vacuum is released. Wixson et al. (17) described another experimental system which "neither stirred air into the mixture nor caused unwanted heat created by faster mixing speeds."
A number of combined mixing devices have been used by various workers. In one device the powder is added to the liquid constituents in a stainless steel bowl, which is then placed on a plate vibrating at 50/s. During this time, the mixture is stirred with a PP spatula (18). Another device (19) consists of a motor coupled to an eccentric unit, the two-directional motion of which mixes the material. A holder for the cement is fixed to the eccentric unit. During mixing of the cement constituents, the motor is typically run at 500 rpm for 120 s. A third device is a proprietary machine which simultaneously mixes and centrifuges (at 2,950 rpm) the cement mixture, typically for 12 s (10).
Following the mixing of the powder and liquid constituents, the usual procedure is to inject the cement dough immediately into a cartridge or tube, usually made of poly (vinyl chloride) or poly (tetrafluoroethylene). A device, usually a cement gun, is used to pressurize the dough into a mold where final setting occurs. The cement is then cured and aged before test specimens are fabricated. Curing media include room-temperature air (20) and water at 37 oC (21). Curing times range from 15 min (21) to 48 h (19). Aging media include room-temperature air (22), water at 37 oC (23), and lactated Ringer's solution containing 10 vol.% bovine serum at 37 oC (15), while aging time ranges from 1 d (22) to 18 months (24).
Effect of Mixing Method on Cement Properties
Cement mixing methods have marked effects on an array of physical and mechanical properties of the cement germane to its clinical performance in the construct. Table 1 shows variation with mixing method in seven of these properties. Other properties affected by mixing method include: dynamic viscosity, static compressive modulus, static ultimate compressive strain, and creep.
Research Directions
The results cited in Table 1 and elsewhere in the published literature suggest a number of research directions. These may be categorized into work that will: (I) help close gaps in the current knowledge base; (II) assist in resolving various controversies in the current knowledge base; and (III) focus on new, unexplored topics.
One study in Category I which should be carried out is an investigation of the effect of mixing method on the exothermic temperature, Te, for all the currently-available commercial formulations. Results from this study would help in the efforts to synthesize new formulations with low values of Te. For each formulation, a detailed study should be performed of the effect of all the key variables (mixing method, curing conditions and aging conditions) on flexural strength, shear strength, fracture toughness, work-of-fracture, fatigue limit and fatigue crack propagation resistance. The current database on these properties (Table 1) is incomplete. Viscosity-versus-mixing time curves should be obtained at various combinations of shear rate and mixing method. Diametral shrinkage is an important cement property, indicative of potential compromise in the cement-bone interface. To date, studies of this property have been reported only for Simplex (50). Although various studies on the fatigue crack propagation behavior (FCP) of bone cement have been reported (51-57), none has focused on CMW-1 or CMW-3, nor has a comparison been made of the fatigue and FCP behaviors of all the formulations, using specimens that are fabricated from cement mixed using one method and cured and aged under identical conditions.
At least four important controversies require resolution. These constitute the work to be performed under Category II. First, does vacuum mixing increase or lower the setting time, ts, (defined as the time taken for the cement to harden)? Studying Palacos R, Lidgren et al. (58) found that vacuum mixing slightly lowers ts whereas Hansen and Jensen (59) observed an increase in ts. Second, the effect of pre-chilling of the liquid monomer on the properties of the cement remains controversial. For example, for Simplex P, some investigators (7, 33) have reported that prechilling leads to an increase in porosity and a decrease in fatigue strength, while for CMW-1, CMW-3 and Palacos R, Lewis and coworkers (60) found that prechilling leads to an increase in ultimate compressive strength. In light of the current practice of prechilling the liquid monomer and vacuum mixing the constituents, these two matters are of obvious importance.
Third, at the moment, there is some uncertainty about the effect of mixing method on the fracture toughness (KIC) of a given formulation. While Rimnac et al. (41) have found that KIC is not so affected in the case of hand- and centrifuged-mixed Zimmer, Simplex P and Palacos R, Maxted (44) found a clear increase in KIC of vacuum-mixed CMW-3 relative to the hand-mixed variety.
Fourth, it needs to be resolved whether the observed change in the value of a specific property of a formulation with change in mixing method results from a change in porosity or in some other characteristic(s) of the formulation induced by the mixing method. Many workers (10, 18, 19) have postulated that porosity changes are the reason, but a few have argued that differences in other features, including viscosity (11), molecular weight (41) and composition (33), are responsible.
The first area of new work is the establishment of standards for the evaluation of various mechanical properties of current cements. This has been done in the case of compressive properties (ASTM F451 and ISO 5833) and flexural properties (D790 and ISO 5833). Such standards must at the least address specimen configuration, specimen size, loading rate and methods of reporting the results.
Second, a consensus should be reached regarding standardization of testing equipment, presentation of results, and nomenclature. For example, the radii of the top and bottom sections of the centrifuge used in centrifugation mixing must be specified. Presentation of fatigue test results should be standardized, and should include characteristic fatigue life, obtained from the treatment of fatigue test results using the three-parameter Weibull relation, and fatigue limit, obtained as the lower asymptote to the classical S-N results treated using an Olgive-type relation. Since the crack resistance of bone cement is a function of both its composition and structure, the "apparent fracture toughness" is more appropriate than "fracture toughness" to describe this phenomenon. A consensus should be reached on the details of the curing and aging conditions for the cement specimens. It is recommended here that the specimens be cured in room-temperature air for at least 24 h and aged in an electrolyte composed of Ringer's solution and 10 vol.% bovine serum at 37 oC for at least 7 d. This curing atmosphere facilitates the release of free monomer liquid while the aging solution, which contains both salts and proteins, provides a suitable biosimulating environment.
Third, efforts should be intensified to develop new or improved cement mixing methods, especially those that impose simultaneous actions. Examples are provided in work of Trieu et al. (10) (simultaneous centrifuging and mixing) and Linden (61) (simultaneous mechanical mixing and vacuum system).
Current efforts in synthesizing new formulations of cement are commendable. Among these formulations are ones in which: (a) acryloyl- and methacryloyl-N-phenylpiperazine are used as accelerators in place of dimethyl-p-toluidine (DMPT), used in the current commercial formulations (39); (b) the composition includes 1.5% w/w benzoyl peroxide and n-butyl methacrylate with 2.5% w/v N, N DMPT (62); and (c) beads of polybutyl methacrylate are dispersed in a methylmethacrylate matrix (63-65). Any new formulation should, among other characteristics, exhibit a low exotherm temperature, release low amounts of monomer liquid, have a low residual content of the monomer liquid and possess excellent relevant mechanical properties. All such formulations should be fully characterized, following the guidelines and suggestions described in the foregoing sections. Only then should full-scale clinical trials of the cement commence. The experience, to date, with Boneloc (a new cement formulation) should serve as a cautionary tale. Boneloc has performed very poorly in cemented hip implants, prompting a call for its withdrawal by the Norwegian Orthopaedic Society (66). It has been postulated (67) that poor mechanical properties of the cement are to blame for this performance.
A failure criterion for bone cement should be established. To facilitate this, cement specimens should be tested under complex triaxial states of stress up to failure. The work has obvious importance in that the cement in the prosthesis-cement-bone construct is under complex multiaxial stresses and the failure of the cement has been postulated to lead to aseptic loosening of the prosthesis. Silvestre et al. (68) have shown that the behavior for hand-mixed CMW-1, under a triaxial state of stress, is consistent with the Coulomb-Mohr failure criterion. This type of work should be conducted for the six commercial formulations as a function of mixing method. This database will assist in establishing the influence of compositional and/or porosity differences, whereby a generalized failure criterion may be proposed.
Two new aspects related to the FCP of cements should be investigated. First, fits of the experimental data of fatigue crack growth rate (da/dN) and stress intensity factor range, DKI, to relation(s) other than the usual Paris-Erdogan fit should be made. One such relation is that presented by Yap et al. (69).
Second, in order to facilitate comparisons between the FCP behavior of different formulations and mixing methods, the da/dN versus DKI results should be normalized with respect to Ecm, the cyclic modulus. Pilliar et al. (70) have provided values of Ecm for some formulations. This recommended normalization allows comparison of cyclic response on the basis of equal strains. This approach has been successfully used to compare the FCP behavior of various metals and polymers (71). This approach has important implications with regard to the cement in the prosthesis-cement-bone construct. If the cement in this case is under load-controlled cyclic histories, then FCP behavior should be characterized on the basis of DKI. If, however, it is under strain- or deflection-controlled cyclic histories (in which case maximum fatigue resistance is achieved by minimizing the crack growth for an operating strain range), the FCP behavior should be characterized on the basis of DKI /Ecm.
In light of the fact that the performance of the cement as an anchoring agent is dependent on both its material and structural behavior in the prosthesis-cement-bone construct, more work should be done in two areas. The first of these is the determination of stresses at various sections of the cement in the construct, especially at the prosthesis-cement interface [which has been implicated often in the loosening of the prosthesis (72)]. To facilitate parametric studies of this stress distribution, the finite element analysis method and a three-dimensional idealization of the structure are recommended. An example of the type of work proposed here is the determination of the stress distribution along both the medial and lateral sides of the interface, using a realistic interface friction model and incorporating the viscoelastic properties of the cement. The objective would be to identify the magnitude and sense of the maximum stress, smax, in specified regions of the cement at the interface for a given simulated activity. This would permit, for example, estimation of the life of the implant (Nv), assuming that it is limited only by the fatigue life of the cement. In other words, Nv could be obtained by utilizing: (a) the value of KIC of the cement, estimates of the applied stress range and smax; (b) the value of the inherent flaw size of the cement [equal to 0.37 mm in the case of Simplex P (73)]; and (c) assumed expressions for KI and the da/dN versus KI dependence. Alternatively, the factor of safety (equal to, for example, the ratio of a relevant material property, such as the fatigue limit, to smax) could be computed, and then be used as the basis for comments on the potential for fatigue failure at that area. Recent work by Mann et al. (74) and McKellop et al. (75) are offered as examples of the type of studies proposed here for obtaining smax. The second area of work should be continuation of efforts to develop the optimum cementing technique. These efforts might involve either improvements to or a radical departure from the current approaches, so-called "second-generation" techniques (76), in order to ensure ideal pressurization conditions.
The final measure of the efficacy of a cement mixing method is its demonstrated effect on the clinical stability and longevity of the prosthesis. For this determination, well-planned, long-term prospective randomized clinical studies are needed.
REFERENCES
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The Council of Chairs of Bioengineering and Biomedical Engineering Programs, with support from the Whitaker Foundation, has established a speakers bureau. The bureau will provide speakers upon request to appropriate programs, departments, etc. We are soliciting names of potential speakers for this program, who should be accomplished lecturers and who can address topics of interest to the biomedical engineering community. Please send names to: Vijay K. Goel, Chair, Council of Chairs, Department of Biomedical Engineering, University of Iowa, Iowa City, IA 52242, (319) 335-5638; fax (319) 335-5631; vijay-goel@uiowa.edu.
Workshop on Biomaterials and Tissue Engineering
February 19-23, 1997
A workshop focusing on the role of biomaterials in tissue engineering will be held on Hilton Head Island, South Carolina, February 19-23, 1997. Starting with a welcome reception on February 19, over the next four days there will be a total of ten sessions, ending mid-day on Sunday, February 23. The program will start each day with a keynote speaker, and the first three days will be devoted to the development of the technology required for tissue engineering applications, with the final day focusing on the regulation of tissue-engineered products by the FDA.
Active researchers, those interested in the application of tissue engineering, and students are encouraged to participate. The workshop is structured so as to allow ample opportunity for participants to interact with each other, both within the formal sessions and informally at other times. For more information call (404) 894-2768.
AIMBE Annual Event
March 1-4, 1997
The next AIMBE Annual Event will be held in Washington, DC on March 1-4, 1997. The meeting, Bioengineering, Innovation, and the Law, will address a wide range of public policy topics of interest to the medical and biological engineering community. For information contact: American Institute for Medical and Biological Engineering, 1901 Pennsylvania Avenue N.W., Suite 401, Washington, DC 20006, (202) 496-9660.
16th Southern Biomedical Engineering Conference
April 4-6, 1997
The 16th Southern Biomedical Engineering Conference will be held April 4-6, 1997 at the Broadwater Beach Resort and Hotel, Biloxi, Mississippi, USA. The conference features papers on new developments in theory, concepts, applications and techniques in all facets of biomaterials and biomedical engineering. The conference further serves to bring together students, researchers, and clinicians from academic, government, and commercial organizations for stimulating discussions on current issues and concepts in biomedical research. The conference has a special emphasis on student participation and will present cash awards to outstanding presentations in three different student categories.
This year's conference will spotlight an outstanding group of plenary speakers representing physiology, biomaterials, biomechanics, modeling, imaging, ergonomics, rehabilitation engineering, and device regulation. Pioneer biomedical engineers Arthur C. Guyton, Larry V. McIntire, and Jack E. Lemons are just a sampling of the high quality speakers who will address the conference. The plenary sessions and invited speakers, coupled with the over two hundred expected conference attendees, will be sure to make this one of the most exciting conferences of the year.
The deadline for submission of a 500-word abstract is November 8, 1996. Please forward abstracts to: 16th Southern Biomedical Engineering Conference, attn: Drs. Puckett and Bumgardner, Department of Restorative Dentistry/Biomaterials, School of Dentistry, 2500 N. State Street, Jackson, MS 39216-4505.
The conference is endorsed by the Biomedical Engineering Society, the Society for Biomaterials, and the Institute of Biological Engineering.
The Broadwater Beach Resort and Hotel in Biloxi is located on the beautiful Mississippi gulf coast and will provide an attractive and family oriented meeting site. Please visit the conference's website at http://abe.msstate.edu/abenews/bumgard.htm for additional information on the plenary speakers, abstract submissions, meeting and hotel registration, and other meeting events.
Course Announcement - Critical Issues in Tumor Microcirculation,
Angiogenesis and Metastasis: Biological Significance and Clinical Relevance
June 2-6, 1997
A continuing education course on Critical Issues in Tumor Microcirculation, Angiogenesis and Metastasis: Biological Significance and Clinical Relevance will be held June 2-6, 1997 at Harvard Medical School and Massachusetts General Hospital. The Course Director is Rakesh K. Jain, Ph.D., Cook Professor of Tumor Biology, Harvard Medical School; Director of the Steele Laboratory for Tumor Biology, Massachusetts General Hospital; and Professor of Health Sciences and Technology, MIT. Topics include tumor angiogenesis, tumor stroma generation, metastasis, tumor blood flow, tumor microenvironment, adhesion molecules, and delivery of novel and conventional agents. For information contact: Carol Lyons, Administrator, Radiation Oncology, Massachusetts General Hospital, Boston, MA 02114, telephone (617) 726-4083, fax (617) 726-4172.
First International Conference on Cardiovascular Medicine, Surgery,
Science, and Mechanics
June 6-9, 1997
The First International Conference on Cardiovascular Medicine, Surgery, Science, and Mechanics will be held June 6-9, 1997 in Washington, DC. The deadline for receipt of abstracts is March 15, 1997. For information contact: Dr. Jafar Vossoughi, 4401-A Connecticut Avenue, NW, Suite 327, Washington, DC 20008, telephone (202) 274-5175, fax (202) 274-5017, e-mail vossoughi@msn.com.
1997 Summer Bioengineering Conference
June 11-15, 1997
The Bioengineering Division and the Bioprocessing Subdivision of the American Society of Mechanical Engineers in conjunction with the Food, Pharmaceutical, and Bioengineering Division of the American Institute of Chemical Engineers, the Bioengineering Committee (Engineering Mechanics Division) of the American Society of Civil Engineers and the Biomedical Engineering Society will be sponsoring the third Summer Bioengineering Conference to be held June 11-15, 1997 in the picturesque area of Sun River, Oregon. Abstracts in all areas of bioengineering are solicited for this conference. Specific sessions and forums are planned on the following topics:
Bioartificial Material
Biological Mass Transfer
Blood/Material Interaction
Cellular Biomechanics
Computational Biomechanics
Contact/Mechanics
Damage Accumulation and Adaptive Response of Bone
Electromechanics
Imaging/Biomechanical Modeling
Interstitial Flow
Micromechanics of Bone
Multibody Modeling
Rapid Prototyping in Medicine
Respiratory Fluid Mechanics
Robotic Applications
Soft Tissue and Joint Mechanics
Upper Extremity Mechanics Vascular Grafts/Implants
In addition, a plenary session on Reducing Health Care Costs through Bioengineering, an evening poster session (including a student poster competition), and workshop sessions on general topics of interest are planned.
Abstracts are to be submitted on 8.5 x 11" paper. The format instructions may be obtained from: K. B. Chandran (chandran@icaen.uiowa.edu), Stephanie Winterbottom (wntrbttm@icaen.uiowa.edu), Department of Biomedical Engineering, 1202 EB, College of Engineering, University of Iowa, Iowa City, IA 52242. Fax: (319) 335-5631. The deadline for submission of abstracts is December 16, 1996. Authors will be notified by March 15, 1997.
The conference will be held in the Sun River Resort, in Sun River, Oregon (15 Miles south of Bend, Oregon) on US Highway 97. Commuter airlines serve the Redmond/Bend airport from San Francisco, Portland and Seattle. Bring the family for a fun-filled week with an exciting conference along with many outdoor activities in the resort (bicycling, fishing, horseback riding, tennis, swimming, canoeing, kayaking, and white water rafting).
Society of Engineering Science 35th Annual Technical Meeting
September 27-30, 1998
The 35th Annual Meeting of the Society of Engineering Science will be held September 27-30, 1998 at Washington State University, Pullman, Washington. This conference provides a forum for the discussion and dissemination of recent advances in mechanics and materials research, development and education, with topics from all areas of fluid, solid and structural mechanics, dynamics and control, heat transfer, materials, processing, and biomedical engineering.
A tentative deadline for the submission of contributed papers to one of the conference co-chairs is no later than August 30, 1997. Those who are interested in organizing symposia should submit their requests by March 1, 1997. All contributed papers will be reviewed by the Program/Steering Committee before final acceptance.
For further information contact one of the co-chairs: Hussein M. Zbib, School of Mechanical & Materials Engineering, Washington State University, Pullman, WA 99164-2920, USA, (509) 335-7832/8654, fax (509) 335-4662, e-mail zbib@mme.wsu.edu; or Tom Burton, Chairman, Department of Mechanical Engineering, Texas Tech University, Lubbock, TX 79409-1021, USA, (806) 742-3563, fax (806) 742-3540, e-mail metdb@coe3.coe.ttu.edu. For current information see: http://www.mme.wsu.edu/ses98.htm
A unique Center of Excellence for Biomedical Engineering Research and Education was recently established at the Massachusetts General Hospital. The Center for Engineering in Medicine (CEM) was created to provide an organized focus of bioengineering activities at Harvard Medical School and the Harvard Teaching Hospitals. The CEM, through its rich interdisciplinary environment and research programs in gene therapy, tissue engineering, and functional imaging is playing a dramatic role in training a new breed of bioengineering practitioner who can bring the rigor of engineering science to some of the most provocative and challenging problems of modern medicine and biology. The CEM was recently awarded a "Center-of-Excellence" type award by the Whitaker Foundation, which carries the potential of five million dollars in funding over a six-year period.
Environmental Health Engineer and Assistant Professor
The University of Nebraska-Lincoln Department of Biological Systems Engineering is seeking candidates for a 12-month, tenure-leading faculty position with 50% teaching and 50% research responsibilities. Will develop a joint research and teaching program to integrate biosystems engineering and occupational hygiene to enhance working environments for agricultural production and agribusiness enterprises in areas of health, safety and welfare concerns highlighted by chronic low-level exposure to dusts, aerosols, chemicals, and gases; acute or chronic work place illnesses and injuries; injury in agribusiness and farmstead facilities; and the inability of disabled persons to function in an agriculture-related work place. Requires Ph.D. in Engineering (Bioengineering, Biomedical, Biological Systems, Industrial, Environmental, Biological, Agricultural, or an equivalent). Also expected are strong commitment to teaching and research, excellent communication skills, ability and desire to work cooperatively on multi-disciplinary research and teaching projects, and expertise in health science, environmental engineering and occupational health and safety. Send letter of application, resume, college transcripts, publication list and names, addresses and telephone numbers of three professional references postmarked by October 1, 1996 (or until qualified candidate is found) to: Dr. Glenn J. Hoffman, Head, Department of Biological Systems Engineering, University of Nebraska-Lincoln, P.O. Box 830726, 223 L.W. Chase Hall, Lincoln, NE 68583-0726, phone: (402) 472-1413. UNL is committed to a pluralistic campus community through Affirmative Action and Equal Opportunity, is responsive to the needs of dual career couples, and assures reasonable accommodation under the Americans With Disabilities Act. Contact Dr. Hoffman for more information.
Chair of Excellence
Biomedical Engineering
The University of Memphis
Search Continued
An endowed Chair is being offered to candidates who have shown consistent evidence of research excellence, leadership and teaching ability. The qualifications of the candidate should be commensurate with an appointment as full professor. Areas of emphasis are the mechanics of cells or tissues, biomaterials or electrocardiology/instrumentation, although other areas which are complementary to the interests of both the program and the existing faculty, such as cell biology, bio-fluid dynamics, thrombosis and microcirculatory behavior, will also be considered. A significant record of research funding is essential. In addition to salary guarantees, the Chair offers significant resources to help establish an initial research program. This position will be filled as soon as feasible and will remain open until filled.
The Department of Biomedical Engineering at the University of Memphis is part of a joint graduate program with the University of Tennessee, Memphis, a development enhanced by the receipt of a Special Opportunity Award by the Whitaker Foundation to the two institutions. The program consists of over 75 students and 16 tenure-track faculty members, including 4 endowed Chairs. Substantial resources are available to the joint program: the facilities of two major universities, several teaching hospitals in a major medical center, the nationally known St. Jude Children's Research Hospital and three major implant manufacturers.
Interested applicants should send a CV, a summary of their research plans, and the names of three references to: Dr. Vincent T. Turitto, Chair, Department of Biomedical Engineering, The University of Memphis, Memphis, TN 38152 (vturitto@cc.memphis.edu. or HTTP://www.memphis.edu)
The University of Memphis is an Equal Opportunity/Affirmative Action Employer.
Assistant Professor in Biomedical Engineering
The Biomedical Engineering Department, of the College of Engineering, University of Miami invites nominations or applications for a tenure seeking position of Assistant Professor in Biomedical Engineering. It is expected that candidates will hold a doctoral degree in biomedical or electrical engineering, with a strong background in biomedical instrumentation with design experience, and have at least 3 years academic and/or industrial experience. The applicant is expected to develop and teach upper level undergraduate courses, develop collaborative research with faculty in the College of Engineering and School of Medicine, as well as develop strong ties with the local BME industry. The Department offers BS, MS, Ph.D. programs. The University is located in Coral Gables, within the Miami metropolitan area. Nominations and applications with the names of three references should be sent to Dr. Michael Sacks, Dept. of Biomedical Engineering, P.O. Box 248294, University of Miami, Coral Gables, FL 33124-0621. The University of Miami is an Equal Opportunity/Affirmative Action Employer.
Faculty Position
Department of Internal Medicine
The Pulmonary Division at the University of Texas Southwestern Medical Center has an opening for an Instructor. The applicant should have a D.V.M. degree as well as a Bioengineering degree with background in biomaterials research and computer technology. The candidate should be able to oversee the implementation of large animal research - rest and exercise; develop new surgical techniques to carry out studies in large animals and develop new methods for measurement and analysis of cardiopulmonary function at heavy exercise. Applicants should submit a curriculum vitae and three letters of reference to: Robert L. Johnson, Jr., M.D., Internal Medicine/Pulmonary Division, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75235-9034. An Affirmative Action/Equal Opportunity Employer.
Director of the Center for Bioengineering at the University of Washington
The University of Washington seeks a candidate for the position of Director of the Center for Bioengineering. The occupant will hold a tenured professorial rank in the Center for Bioengineering, which is in both the College of Engineering and the School of Medicine. The Director will lead actively to further develop the research and teaching programs of the Center. The Center for Bioengineering has active research programs in biomaterials, biomechanics, cellular bioengineering, biomedical systems, molecular bioengineering, biomedical imaging and biomedical instrumentation. Its graduate program serves more than 100 students of whom the majority are pursuing doctoral degrees. Its undergraduate program serves a small number of superb students who intend to enter either M.D. or M.D./Ph.D. programs. The Center has 30 core faculty, 35 adjunct faculty and 20 affiliate faculty. The Center for Bioengineering has strong collaborative ties with colleagues in the School of Medicine and the College of Engineering.
Nominations and applications should be submitted to Professor Yongmin Kim, Chair of the Bioengineering Director Search Committee, Department of Electrical Engineering, Box 352500, University of Washington, Seattle, WA 98195-2500. Review of applications will begin on September 1, 1996, and applications will be received until the position is filled. Applications should include a curriculum vita, a statement of interests and goals and the names of five references. The University of Washington is building a culturally diverse faculty and strongly encourages applications from female and minority candidates.
The University is an Equal Opportunity/Affirmative Action employer.
Biomedical Engineering Faculty Position
Max P. and Robbie L. Watson
Eminent Scholar Chair
Biomedical Engineering
Louisiana Tech University
A nation-wide search is being conducted to identify highly qualified candidates for the $1 million Watson Eminent Scholar Chair in Biomedical Engineering. The Chairholder will be an experienced researcher with a focus on biomedical applications of microsensors/microdevices. In addition, the Chairholder must have demonstrated the ability to establish and sustain an externally funded research program. The chairholder will teach courses, supervise graduate students, conduct research and participate in economic development activities. In performing these duties, the chairholder will be expected to contribute to the overall quality of our program by increasing the capabilities of our graduates and by mentoring beginning faculty members.
The Biomedical Engineering Program offers a nationally-recognized academic program with research emphasis on microsensors/devices, systems physiology, and rehabilitation engineering. Degrees are offered at the B.S. (ABET-accredited), M.S. and Ph.D. levels. The Department's Board of Regents-funded Center for Rehabilitation Science and Biomedical Engineering provides opportunities for professional growth and for interactions with the LSU School of Medicine in Shreveport and the University's Institute for Micromanufacturing, a world-class resource for development of micro-structures, devices, and systems.
Candidates must have earned a doctorate in Biomedical Engineering or a related field, and be a U.S. Citizen or permanent resident. Send curriculum vitae, statement of teaching and research interests/goals, and names and addresses of at least three references to Dr. Stan Napper, Chair of Search Committee, Biomedical Engineering, Louisiana Tech University, P.O. Box 10348, Ruston, LA 71272 (phone: 318-257-2645, FAX: 318-255-4175, e-mail: san@engr.latech.edu, WWW: http://www.latech.edu/tech/engr/bme/index.html). Applications will be reviewed beginning December 1, 1996. Louisiana Tech University is an equal employment university; women and minorities are encouraged to apply.
Faculty Position Bioengineering Program
Texas A&M University
The Bioengineering Program at Texas A&M University has an open position for a tenure track faculty member. Candidates would be expected to develop or maintain an independent funded research program, teach existing courses at both the undergraduate and graduate level, and develop new graduate courses in their specialty area. The desired area of teaching emphasis is in biomechanics. A Ph.D. in biomedical engineering or a closely related field is required. Rank and salary will be commensurate with background and experience. A starting date of January, 1997 is available, but later starting dates will also be considered.
The Bioengineering Program offers an ABET accredited undergraduate degree and graduate degrees at the masters and doctoral levels. Current areas of research include optical biosensors, optical tomography and spectroscopy, laser interaction with tissue, biomechanics, orthopedic devices, biosignal processing and rehabilitation engineering.
To apply submit a resume and the names of three references to: William A. Hyman, Chair, Search Committee, Bioengineering Program, Texas A&M University, College Station, TX 77843-3120, (409) 845-5532, fax (409) 847-9005, e-mail search@aggie.tamu.edu.
Faculty Position in Biomechanics
The Department of Engineering Science and Mechanics at Virginia Polytechnic Institute and State University requests applications for a tenure track faculty position in biomechanics from applicants with a Ph.D. and a superior academic and/or professional record. It is anticipated that the position will be filled at the Assistant Professor level, but individuals with sufficient qualifications and/or experience will be considered for appointment at the Associate level. All areas of biomechanics will be considered, such as biosolids, soft and/or hard tissues, biofluid mechanics, bioprosthetics, hemodynamics and/or microcirculatory mechanics, physiologic modeling, biodynamics, kinematics of human motion, and aerospace medicine, to name a few. Responsibilities include teaching at the undergraduate and graduate levels, directing M.S. and Ph.D. theses, and developing a research program.
Review of applications will begin on October 30, 1996, and will continue until the position is filled. The position may begin as early as January 1, 1997. Interested persons should send a letter of application including personal data, education, publications, research and professional experience to Professor E. G. Henneke, Chair of Biomechanics Search Committee, Department of Engineering Science and Mechanics, Virginia Tech, Blacksburg, VA 24061-0219.
Virginia Tech is an Affirmative Action/Equal Opportunity Employer and specifically invites and encourages applications from women, minorities and people with disabilities. Individuals with disabilities desiring accommodations in the applications process should notify P. Baker (540) 231-6651.
Whitaker Professorship in Cellular Mechanics
The department of biomedical engineering of Boston University is seeking a faculty member to enhance a growing departmental program in cell mechanics. The successful candidate will be fluent in the classical mathematical models and quantitative design methodologies of engineering. He or she will also be expected to establish an independent laboratory dedicated to aggressively applying such methodology for the purpose of developing improved understanding of the mechanics and control of the cellular hardware. Persons with experience in the molecular biology of the cytoskeleton, in modern imaging technologies and in techniques of micromanipulation and force measurement either at the molecular level or at the level of whole biological cells are particularly encouraged to apply.
Preference will be given applicants at the level of assistant professor (tenure track) but appointment at a higher level will be considered under exceptional circumstances. The program in cellular biomechanics at Boston University is supported by the Whitaker Foundation and appointment will include a generous allotment of laboratory space as well as startup funds for purchase of equipment.
Candidates should send 5 copies of their CV and 5 copies of one or two recent publications to the chairman of the search committee. A one or two page letter describing research interests, the significance and background of prior research and the intended future directions of research will also be considered. Send correspondence to: Dr. Micah Dembo, Chair, Cell Mechanics Search Committee, Boston University, Dept. of Biomedical Engineering, 44 Cummington St. 4th Floor, Boston, MA 02215 USA.
Tenure-Track Faculty Position in Biomedical Engineering Rice University
The Department of Bioengineering at Rice University invites applications for a tenure-track faculty position in laser biomedical engineering. Applicants should have a strong multidisciplinary background in laser bioengineering including such fields as photoacoustics, photothermodynamics, photochemistry, optics and imaging, and substantial experience in independent research and competitive funding. We are particularly interested in researchers with exceptionally strong research expertise at both the macro level of tissues and micro/nanoscale level of cells, organelles, and molecules. The successful applicant would establish research collaborations with institutions at the Texas Medical Center and groups at the Institute of Biosciences and Bioengineering at Rice University. Applicants would be expected to develop and teach courses in the area of biomedical engineering at the undergraduate and graduate levels. Applicants should send a curriculum vitae which includes a list of publications, a statement describing a research program in laser biomedical diagnostics and therapy, and names of at least three references to: Professor Larry V. McIntire, Chair, Institute of Biosciences and Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77005-1892. For full consideration, applications should be received by January 1, 1997. Rice University is an Equal Opportunity/Affirmative Action Employer; women and minority candidates are encouraged to apply.
State University of New York at Buffalo
Department of Chemical Engineering
Tenure-Track Faculty Positions
Applications are invited for two positions in Bioengineering at the rank of Assistant or Associate Professor. Applicants are expected to have sufficient research experience to be innovators in therapeutic engineering as it relates to the discovery, design, and delivery of new therapies. Areas of interest include: cellular or gene therapy, tissue engineering, or cell-based drug screening. The Department offers a modern 6000 sq. ft. Bioengineering Research Facility that is fully instrumented for cellular and molecular biology, analytical biochemistry, and digital microscopy. Bioengineering represents a targeted growth area among SUNY's highly ranked Schools of Engineering, Pharmacy and Medicine. Please submit a CV with three professional references to: Chairman, Department of Chemical Engineering, Furnas Hall, SUNYAB, Buffalo, NY 14260. SUNYAB is an Equal Opportunity/Affirmative Action Employer.
Faculty Position in Bioengineering at Georgia Tech and Emory
Georgia Institute of Technology and Emory University School of Medicine will appoint eight new tenure-track faculty in bioengineering over the next four years. This expansion is supported by the receipt of a Whitaker Foundation Biomedical Engineering Development Award, which focuses on tissue engineering. Areas of special interest include bioartificial organs, biomaterials, biosensors, cellular applications of micromachined devices, cellular imaging, cellular immunology, controlled release systems, cryopreservation, drug delivery, gene therapy, micro-biomechanics, and stem cell propagation. Interested candidates should provide complete curriculum vitae, descriptions of their research interests, and the names and addresses of at least three references. Candidates should have a Ph.D. in bioengineering, chemical engineering, electrical engineering, materials science, mechanical engineering, or a related field, and/or a M.D. degree. Successful applicants will have primary appointment in appropriate departments either at Georgia Tech or at Emory. Applications should be sent to: Robert M. Nerem, School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405. Georgia Tech and Emory University are equal opportunity employers.
Postdoctoral Fellowships
Applications are invited for Postdoctoral Fellowships at the University
of Virginia. One is in the area of biomechanics and rehabilitation at the
Transportation Rehabilitation Engineering Center and the Automobile Safety
Laboratory. Research includes seeking ways to reduce potential debilitating
injuries caused by vehicle accidents to both the physically challenged
and able-bodied individuals. The other is in a new multidisciplinary program
in wound healing with interests in basic cellular and molecular mechanisms
of wound formation and repair, technology development for metabolic and
mechanical wound monitoring and clinical applications all with an objective
to improve rehabilitation from acute or chronic wounds. Applicants must
be U.S. citizens, interested in a research career in rehabilitation engineering
and should submit a curriculum vitae, names of three references and a one
to two page description of research experience and future goals to: Milton
Adams, A114 Thornton Hall, School of Engineering and Applied Science, University
of Virginia, Charlottesville, VA 22903. The University of Virginia is an
Equal Opportunity Employer. Women and minorities are encouraged to apply.
Address questions, comments, and corrections to:
Qiuying
Huang
uhqiuying@cc.memphis.edu
Rita Schaffer
bmes@netcom.com
Last Updated: December 7, 1996