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Yi-Xian Qin

T: 631.632.1481
F: 631.632.8577
E: Yi-Xian.Qin@stonybrook.edu

Office:
Room 215
Bioengineering Bldg
Stony Brook, NY
11794-5281



Yi-Xian Qin

Professor
Director, Orthopaedic Bioengineering Research Laboratory

Research Focus

My research is focused on the physical mechanisms involved in the control of tissue growth, healing, and homeostasis, especially bone adaptation and regeneration influenced by mechanical environment, as well as how these mechanisms can be utilized in the treatment and prevention of disease and injury and bone tissue engineering. It is clear that bone senses and responds to biomechanical stimuli towards the achievement and maintenance of a structurally appropriate skeletal structure. In addition to strain magnitude, bone tissue has the ability to differentiate between shear and normal strain, cycle number, loading frequency, and even fluid pressure and its gradients. The interdependent roles of these mechanical signals are investigated through empiric and analytic models to provide support for the complex interactive mechanism of bone remodeling.

My research is also focused on the development of non-invasive scanning acoustic diagnostic system for tissue quality, and therapeutic ultrasound. The goal of this project is to develop a new technology, which will lead to a better understanding of the progressive adaptation of bone loss in aging populations and microgravity environment. The technology will be used for assessing musculoskeletal complications such as osteoporosis and accelerate fracture healing.

Fig. 1. Finite element modeling for an implant fixation. Interface mechanical conditions significantly influence adaptive response of bone. Surface shear stress plays a critical role in inhibition of bony ingrowth. Fig. 2. Bone fluid flow is hypothesized a mediator for triggering cellular response in bone, which is closely related to temporal loading components, i.e., frequency. Under same strain amplitudes, high frequency mechanical stimuli (i.e., 30 Hz) raise higher tissue fluid pressure (10x) than lower frequency (0.1 Hz).

Research Projects

Bone fluid flow and mechanotransduction

A likely candidate involved in the adaptive process may be the intracortical fluid pressure and resultant fluid flow which arises in the cortical bone matrix by the time-varying mechanical strain, which may serve as a critical signal to regulate cell activity. This hypothesis is evaluated with whole bone fluid pressure and its gradient in a porous media model incorporated with in vivo streaming potential measurements. Based on the frequency dependent site specificity of the remodeling response (i.e., endosteal vs. periosteal), the most likely parameter which promotes surface new bone formation may be fluid pressure gradient, factors which are strongly mediated by loading frequency. Osteocytic processes in the bone could serve as a mechanical signal receptors by ways of sensing the fluid flow induced by pressure gradients. Thus, perturbation of intracortical fluid flow, via alterations in functional activity, may provide a key influence in determining skeletal morphology. These results may improve our understanding of functional vertebrate morphology and etiologic processes in musculoskeletal diseases, and perhaps even provide insight into novel treatment regimens for the treatment of these diseases (i.e., osteoporosis), the acceleration of fracture repair, and the promotion of bony ingrowth.

Implant fixation and fracture healing

Bone's ability to respond relatively high frequencies of mechanical stimuli is indicative as to how bone cells sense the signal for adaptation. This frequency sensitivity data extends beyond identifying the factor that stimulates bone formation. Presented result indicates that the most active inhibitor of bony ingrowth is the shear strain and stress generated at the bone-implant interface. While specific mechanical parameters, i.e., normal strains and strain gradients, may mildly encourage the bony ingrowth, shear actively inhibits it. To maximally stimulate bony ingrowth, implant design must promote specific stresses or strains and their gradients, while minimizing shear stress or strain at the bone-implant interface.

Bioinstrumentation: Noninvasive diagnostic and therapeutic ultrasound

Musculoskeletal complications included osteoporosis and/or the delayed union of fractures represent a key health problem. Early diagnosis of these skeletal disorders leads to prompt treatment and will dramatically reduce the risk of complication. It is hypothesized that such a musculoskeletal disorder, i.e., osteoporosis, is not only changing the structure and the mineral density (BMD), but the modulus of the bone. The principal diagnostic methods for osteoporosis is dual-energy X-ray absorptionmetry (DEXA), which provides only an index of bone mineral content, and not bone's physical properties. More recently, advents in ultrasonic techniques provide an intriguing method for characterizing the material properties of bone in a manner which is non-invasive, non-destructive, repeatable, safe and relatively accurate. While ultrasonic techniques provide both structural and property information of bone, the current research work focus on non-invasively detect spatial distribution of bone quality in the region of interesting using the developing scanning acoustic diagnostic system.

Differentiate torsional and axial loading

The ability of bone tissue to differentiate shear and normal strain conditions was evaluated by monitoring the adaptive response of axial and torsional loading conditions in a turkey ulna model. Of three distinct regimens (disuse, axial and torsional loads), only disuse caused a significant change in gross areal properties as compared to controls (12% loss of bone), suggesting both axial and torsional loading conditions were suitable substitutes for functional signals normally responsible for bone homeostasis. However, the intracortical response was strongly dependent on the manner in which the bone was loaded. It appears that bone tissue can readily differentiate between distinct components of the strain environment, with strain per se necessary to retain coupled formation and resorption, shear strain achieving this goal by maintaining the status quo, while axial strain elevates intracortical turnover, but retains coupling.

Frequency, cycle number and loading duration

The interdependent role of loading frequency, cycle number and intensity was investigated by quantifying the bone remodeling response to a relatively high frequency (30 Hz) loading regimen. The applied strain distributions were correlated to site-specific surface modeling/remodeling and intracortical porosity under long duration loading, following disuse plus 18,000 of applied loading cycles with peak normal strain of 700, and disuse plus 108,000 applied loading cycles induced at 100. While new bone was found in the low cycle, high strain magnitude group, the sites correlated poorly with the distribution of induced strain. However, a strong correlation was observed between the preservation of bone mass and longitudinal normal strain (R=0.91) in the high cycle, low strain magnitude group. These results indicate that mechanical loading can hold anti-resorptive potential, even at levels less than 100.

Education

  • Ph.D. - Mechanical Engineering, SUNY at Stony Brook, 1997
  • M.S. - Mechanical Engineering, SUNY at Stony Brook, 1993

Professional Experiences

  • 2007 - : Professor of Biomedical Engineering and Orthopaedics, SUNY Stony Brook
  • 2003 - 2007: Assoc. Prof. of Biomedical Engineering and Orthopaedics, SUNY Stony Brook
  • 1998 - 2003: Asst. Prof. of Biomedical Engineering and Orthopaedics, SUNY Stony Brook
  • 1997- 98: Post-Doc. Research Associate, Department of Biomedical Engineering, Stony Brook.
  • 1986-91: Res Scientist & Director, Microstructure Research Laboratory School of Dental Medicine, Shanghai 2nd Medical University
  • 1983-85: Research Fellow, Medical Electronics and Medical Acoustics Research Lab Institute of Biomedical Engineering, Fudan University
  • 1982-86: Biomedical Engineer, Biomedical Engineering Laboratory Shanghai Medical University

Honors and Awards

  • 2002: Chancellor's Award for Promising Inventors, State University of New York
  • 1999-02: Whitaker Investigator, The Whitaker Foundation
  • 2000: Recognition Award for Integration of Research and Integration, SUNY Stony Brook
  • 1997: President's Award to Outstanding Doctoral Students, SUNY Stony Brook
  • 1988: Science and Technology Award, Shanghai High Education Department

Publications

Peer-Reviewed Publications
  • Qin Y-X. , Lam H. (2008): Intramedullary Pressure and Matrix Strain Induced by Oscillatory Skeletal Muscle Stimulation and its Potential in Adaptation. J Biomech, (in press).
  • Lam H., Qin Y-X. (2008): Biomineralization of a Self-Assembled Extracellular Matrix for Bone Tissue Engineering. Bone, (in press).
  • Meng Y., Qin Y-X. , DiMasi E., Ba X., Rafailovich M., Pernodet N. (2008): Biomineralization of a Self-Assembled Extracellular Matrix for Bone Tissue Engineering. Tis Eng, (in press).
  • Qin, Y-X. , Xia, Y., Lin, W., Mittra, E., Rubin, C., Gruber, B. (2007): Noninvasive Ultrasound Imaging for Bone Quality Assessment using Scanning Confocal Acoustic Diagnosis, mCT, DXA Measurements, and Mechanical Testing. LNCS, ISSN:0302-9743 (p)/1611-3349 (online). Dec, 4901:216-233.
  • Mittra E, Yaghoubi S, Qin Y-X. MicroPET imaging of small animals. In: The Protocols in Musculoskeletal Research: A Practical Manual for Laboratory Techniques. World Scientific Publisher.
  • Mittra, E., Rubin, C., Gruber, B. and Qin, Y-X. (2008): Evaluation of trabecular mechanical and microstructural properties in human calcaneal bone of advanced age using mechanical testing,mCT, and DXA. J Biomech, 41:368-375.
  • Ni, Q., De Los Santos, A, Lam, H., Qin, Y-X. (2007): Assessment of Simulated and Functional Disuse on Cortical Bone by Nuclear Magnetic Resonance. Adv in Space Res, 40:1703-10.
  • Xia, Y., Lin, W. and Qin, Y-X. (2007): Bone Surface Topology Mapping and its Role in Trabecular Bone Quality Assessment using Scanning Confocal Ultrasound. Osteoporosis Intl, Jul;18(7):905-13.
  • Ozcivici, E., Ferreri, S., Qin, Y.X., Judex, S. (2007) Determination of bone’s mechanical matrix properties by nanoindentation. In: Molecular Methods in Medicine: Osteoporosis. Westendorf, J. (ed.). The Humana Press, Totowa, NJ. (in press)
  • Qin, Y-X. , Lin W., Xia, Y., Mittra, E., Rubin, C., Müller, R. (2007): non-invasive bone quality assessment using quantitative ultrasound imaging and acoustic parameters. In “Advanced Bioimaging Technologies in Assessment of the Quality of Bone and Scaffold Materials,” edited by L. Qin and H. Genant. Springer, ISBN: 9783540454540.
  • Qin, Y-X. , Kaplan, T., Saldanah, A. and Rubin, C.T. (2003): Fluid Pressure Gradients, Arising from Oscillations in Intramedullary Pressure, is Correlated with the Formation of Bone and Inhibition of Intracortical Porosity. J Biomech, Oct;36(10):1427-37, 2003.
  • Judex S, Boyd S, Qin Y-X. , Turner S, Ye K, Muller R, Rubin C.: Adaptations of trabecular bone to low magnitude vibrations result in more uniform stress and strain under load. Ann Biomed Eng., Jan;31(1):12-20, 2003.
  • Qin, Y-X. , Lin, W., and Rubin, C.T. (2002): The Pathway of Bone Fluid Flow as Defined by In Vivo Intramedullary Pressure and Streaming Potential Measurements, Annals Biomed Eng, 30:693-702.
  • Qin, Y-X. , Kaplan, T., Saldanah, A. and Rubin, C.T. (2002): Fluid Pressure Gradients, Arising from Oscillations in Intramedullary Pressure, is Correlated with the Formation of Bone and Inhibition of Intracortical Porosity. J Biomech, (in press).
  • Rubin, C. T., Turner, S., Muller, R., Mittra, E., McLeod, K., Lin, W., and Qin, Y-X. (2002): Quantity and Quality of Trabecular Bone in the Femur are Enhanced by a Strongly Anabolic, Noninvasive Mechanical Intervention. J Bone Min Res, 17(2): 349-357.
  • Beck, B., Qin, Y-X. , McLeod, K.J. and Otter, M (2002): On the relationship between streaming potential and strain in an in vivo bone preparation. Calcif Tiss Intl, 71(4):335-343.
  • Lin, W., Qin, Y-X. , and Rubin, C.T. (2001): Ultrasonic Wave Propagation in Trabecular Bone Predicted by the Stratified Model. Annals Biomed Eng, 29(9): 781-790.
  • Rubin, C. T., Sommerfeldt, D. W., Judex, S. and Qin, Y-X. (2001): Inhibition of Osteopenia by Low Magnitude, High Frequency Mechanical Stimuli. Drug Discovery Today, 6:16:848-858.
  • Rubin, C.T., Judex, S., McLeod, K.J., Qin, Y-X (2001): Inhibition of Osteopenia by Biophysical Intervention. In: Osteoporosis. Marcus, R., Feldman, D., Kelsey, J. (eds.) 2nd edition, Academic Press, San Diego, CA.
  • Qin, Y-X. , Lin, W., and Rubin, C.T. (2001): Load-Induced Intracortical Flow Pathway And Its Potential Role In Bone Adaptation. ASME-BED, 50: 337-338.
  • Demes, B., Qin, Y-X. , Stern, J. T. Jr., Larson, S. G., Rubin, C.T. (2001): Patterns of strain in the macaque tibia during functional activity. Am J Physcial Anthropology, 116:257-265.
  • Qin, Y-X. , McLeod, K.J., Otter, M.W. & Rubin, C.T. (2001): Patterns of Loading Induced Fluid Flow in Cortical Bone, Annals Biomedical Engineering, (in review).
  • Khalsa, P.S., Zhang, C., & Qin, Y-X. (2000): Encoding of Location and Intensity of Noxious Indentation into Rat Skin by Spatial Populations of Cutaneous, Mechano-Nociceptors. J. Neurophysiology, 83:3049-3061.
  • Otter, M.W., Qin, Y-X. , Rubin, C.T. and McLeod, K.J. (1999): Does Bone Perfusion/Reperfusion Initiate Bone Remodeling and the Stress Fracture Syndrome? Medical Hypotheses,53(5):363-368.
  • Qin, Y-X. , Rubin, C.T., & McLeod, K.J. (1998): Non-linear Dependence of Loading Intensity and Cycle Number in the Maintenance of Bone Mass and Morphology. J. Orthop. Res. 16:482-489.
  • McLeod, K.J., Rubin, C.T., Otter, M.W. and Qin, Y-X. (1998): Skeletal Cell Stresses and Bone Adaptation. Am. J. Med. Sci., 316:176-183.
  • Qin, Y., McLeod, K., Otter, M., & Rubin, C. (1997): Intracortical Pore Fluid Pressure and Gradients Generated by Dynamic Loading and Their Potential Role in Bone Adaptation. Annals of Biomed. Eng., 25(Suppl. 1):449.
  • Fritton, J.C., Rubin, C.T., Qin, Y-X, and McLeod, K.J. (1997): Vibration in the Skeleton: I. Development of a Resonance-Based Whole Body Vibration Device. Annals of Biomedical Engineering 25:6.
  • Qin, Y-X. , McLeod, K.J., Guilak, F., Chiang, F-P and Rubin, C.T. (1996): Correlation of Bony Ingrowth to the Distribution of Stress and Strain Parameters Surrounding a Porous-Coated Implant. J. Ortho. Res. 14:862-870.
  • Rubin, C.T., Gross, T., Qin, Y-X. ,Fritton, S., Guilak, F., and McLeod, K.J. (1996): Differentiation of the Bone Tissue Remodeling Response to Axial and Torsional Loading in the Turkey Ulna. J. Bone Joint Surg. 78-A:1523-1533.
  • Qin, Y-X. , Zhu, L., Young, C. and Hsu, W. (1988): PEF-1 Type Occlusal Force Meter and Its Clinical Applications. Chinese J. Stomatology, 8:18-22.
  • Qin, Y-X. , Wang, W., and Shao, Q. (1987): The Method of Ultrasonic Convergency for the Blood Flow Measurement with Doppler Ultrasound in the Small Vessel on Oral and Maxillofacial Regions. Chinese J. Biomedic. Eng., 6:132-136.

Patents and Disclosures

  • Qin, Y-X. , Lin, W. and Rubin, C.T.: Frequency Scanning of Ultrasound Attenuation as a Diagnostic to Determine Bone Physical Properties (R-7424). Patent Pending, 2001.
  • Qin, Y-X. , Lin, W. and Rubin, C.T.: Method and apparatus for scanning confocal acoustic diagnostic for bone quality (R-7450). Patent Pending (Provisional Application #60/271,957), 2001.
  • Qin, Y-X. , Zhu, L., Young, C. and Hsu, W.: A Transducer with Piezoelectric Foil for Measuring Forces, Chinese Patent No. 12144, 1988.
  • Shao, Q., Qin, Y-X. and Wang, W.: The Stabilizer of Liquid Flow Velocity Used in a Flow-meter for Measuring Flow Velocity and Quantity, Chinese Patent No. 1896, 1986.

Selected Abstracts

  • Qin, Y-X. , Xia, Y., Lin, W., Chadha, A., Gruber, B. and Rubin, C. (2002): Assessment of bone quantity and quality in human cadaver calcaneus using scanning confocal ultrasound and DEXA measurements. Ann Am Soc Bone Mine Res, J Bone Min Res, 17:S422.
  • Qin, Y-X. , Kaplan, T. (2002): Dose dependence of bone formation and bone remodeling elucidated by dynamic fluid flow stimulation. Ann Am Soc Bone Mine Res, J Bone Min Res, 17:S331.
  • Mittra, E.S., Rubin, C.T. and Qin, Y-X. (2002): Characterization of Changes in Trabecular Bone with Age & Disease. Ann Am Soc Bone Mine Res, J Bone Min Res, 17:S418.
  • Qin, Y-X. , Mittra, E., Lin, W., Xia, Y., Berman, C. and Rubin, C. (2002): Non-Invasive Assessment of Bone Quality and Quantity Using Confocal Acoustic Scanning on ex-vivo Trabeculae. IEEE Eng Med Biol/Ann Biomed Eng Conference, pp333.
  • Lin, W., Mittra, E., Berman, C., Rubin, C. and Qin, Y-X. , (2002): Measurment of ultrasound phase velocity in trabecular bone using adaptive phase tracking. IEEE Eng Med Biol/Ann Biomed Eng Conference, pp371.
  • Mittra, E., Lin, W., C., Rubin, C. and Qin, Y-X. , (2002): Interrelationship of Trabecular Mechanical and Microstructural Properties. IEEE Eng Med Biol/Ann Biomed Eng Conference, pp156.
  • Xia, Y., Lin, W., Chadha, A., Reardon, C., Gruber, B., Rubin, C. and Qin, Y-X. (2002): Characterization of Human Trabecular bone Quantity and Quality Using Confocal Acoustic Scanning. IEEE Eng Med Biol/Ann Biomed Eng Conference, pp371.
  • Kaplan, T., Saldanha, A., and Qin, Y-X. (2002): Trabecular bone formation induced by high frequency, low intensity oscillatory intramedullary pressure stimulation. IEEE Eng Med Biol/Ann Biomed Eng Conference, pp160.
  • Lai, J.G., Kaplan, T., Saldanha, A., Cute, M., Grine, F.E. and Qin, Y-X. (2002): Promotion of bony ingrowth by low intensity, high frequency oscillatory intramedullary pressure stimulation. IEEE Eng Med Biol/Ann Biomed Eng Conference, pp160.
  • Saldanha, A., Qin, Y-X. and Khalsa, P. (2002): Finite element analysis of mechanical states in human lumbar facet joint capsule. IEEE Eng Med Biol/Ann Biomed Eng Conference, pp364.
  • Qin, Y-X. , Lin, W., Gruber, B. and Rubin, C.T. (2002): Ultrasound assessment for bone quality. NSBRI-NASA Bi-annual Conference, Houston.
  • Qin, Y-X. , Saldanha, A., Kaplan, T. (2001): Oscillatory Bone Fluid Flow and its Role in Initiating Remodeling in the Absence of Matrix Strain. Intl Mech Eng Cong & Eepo, BED-23025, Vol I.
  • Lin, W., Rubin, C., Qin, Y. (2001): Measurement of broadband ultrasound attenuation using tone burst frequency scanning in trabecular bone property assessment. Intl Mech Eng Cong & Eepo, BED-23033, Vol I.
  • Qin, Y-X. , Lin, W., and Rubin, C.T. (2001): Interdependent relationship between Trabecular Bone Quality and Ultrasound Attenuation and Velocity Using a Scanning Confocol Acoustic Diagnostic System. Ann Am Soc Bone Mine Res, J Bone Min Res, 16:S470.
  • Qin, Y-X. , Kaplan, T., Cute, M. and Rubin, C.T. (2001): Dynamic Fluid Flow Induced Trabecular Bone Formation. Ann Biomed Eng Conference, Ann Biomed Eng, 29:S-23.
  • Saldanha, A., Kaplan, T., Rubin, C.T. and Qin, Y-X. (2001): Intracortical Fluid Perfusion Patterns under Dynamic Intramedullary Pressure in a Canine Model. Ann Biomed Eng Conference, Ann Biomed Eng, 29:S-39.
  • Lin, W., Rubin, C.T. and Qin, Y-X. (2001): Correlation of Broadband Ultrasound Attenuation with Trabecular Microstructure. Ann Biomed Eng Conference, Ann Biomed Eng, 29:S-39.
  • Qin, Y-X. , Lin, W., and Rubin, C.T. (2001): Load-Induced Intracortical Flow Pathway And Its Potential Role In Bone Adaptation. Bi-Ann Bioeng Conference, 50: 337.
  • Qin, Y-X. , Cute, M., and Rubin, C.T. (2001): The Relationship between Bone Fluid Flow and Adaptation as Stimulated by Intramedullary Hydraulic Loading. 47th Ann Mtg Orth Res Soc, 26:319.
  • Qin, Y-X. , Cute, M., and Rubin, C.T. (2000): Bone Morphological Adaptation Induced by Dynamic Fluid Flow in the Absence of Matrix Strain. Annuals Biomed Eng, 28(Sup. 1): S8.
  • Lin, W., Qin, Y-X. and Rubin, C.T. (2000): Ultrasound Attenuation as an Indicator of Bone's Physical Properties. Annals Biomed Eng, 28(Sup. 1): S7.
  • Qin, Y-X. , McLeod, K.J., and Rubin, C.T. (2000): Intracortical Fluid Flow is Induced by Dynamic Intramedullary Pressure Independent of Matrix Deformation. 46th Ann Mtg Orth Res Soc, 25:740.
  • Qin, Y-X. , Mauser, R., Berman, C., Lin, W. and Rubin, C.T. (2000): The Relationship between Bone Mineral Density and Ultrasonic Velocity. 46th Ann Mtg Orth Res Soc, 25:753.
  • Lin, W., Qin, Y-X. and Rubin, C.T. (2000): Frequency Specific Scanning of Ultrasound Attenuation to Measure Bone Properties. 46th Ann Mtg Orth Res Soc, 25:750.
  • Qin, Y-X. , McLeod, K.J., Rubin, and C.T. (1999): Intramedullary Pressure Induced Fluid Flow in Bone. Ann Biomed Eng, p88.
  • Qin, Y-X. , and Khalsa, P.S. (1999): Lumbar Facet Joint Capsule Model. Ann Biomed Eng, p91.
  • Qin, Y-X. , McLeod, K.J., Lin, W., Gray, J., Turner, A.S. and Rubin, C.T. (1999): Trabeculi Strength Is Enhanced by Low Magnitude and High Frequency Mechanical Stimuli as Determined by CT Number, Ultrasonic Velocity and Force-Deformation Measurements. 45th Ann Mtg Orth Res Soc, 24:568.
  • Qin, Y-X. and Khalsa, P.S. (1999): Compressive Compliance of Muscle Emulated with Multi-layer Silicone Substrate. 45th Ann Mtg Orthop Res Soc, 24:531.
  • Lin, W., Qin, Y-X. , McLeod, K.J., and Rubin, C.T. (1999): Sinusoidal Correlation Method in Ultrasound Velocity Measurement of Bone Properties. 45th Ann Mtg Orthop Res Soc, 24:783.
  • Lin, W., Gray, J., Qin, Y-X. , McLeod, K.J., and Rubin, C.T. (1998): Assessment of Differential Bone Strength Using Ultrasound Attenuation. Biomedical Engineering Society, Ann Biomed Eng, 26:S114.
  • Qin, Y-X. , McLeod, K.J., Otter, M.W. and Rubin, C.T. (1998): The Interdependence of Loading Frequency and Intracortical Fluid Flow in Guiding Site-specific Bone Adaptation. Third World Congress of Biomechanics, Japan.
  • Qin, Y-X. , McLeod, K.J., Otter, M.W. & Rubin, C.T. (1998): The Interdependent Role of Loading Frequency, Intracortical Fluid Pressure and Pressure Gradients in Guiding Site?Specific Bone Adaptation. 44th Ann Mtg Orthop Res Soc, 23:544.

Funding Sources

  • National Space Biomedical Research Institute
  • National Institutes of Health
  • US Army Medical Research
  • The Whitaker Foundation
  • New York Advanced Centers for Technology

Courses

  • BME 100: Introduction to Biomedical Engineering
  • BME 303: Biomechanics
  • BME 420: Computational Biomechanics
  • BME 505/506: Biomedical Engineering Principles and Practice
  • BME 604: Finite Element Modeling in Biology and Medicine