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1997

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Articles 1 - 30 of 70

Full-Text Articles in Biomedical Engineering and Bioengineering

Implant Having Reduced Generation Of Wear Particulates, David A. Pienkowski Dec 1997

Implant Having Reduced Generation Of Wear Particulates, David A. Pienkowski

Biomedical Engineering Faculty Patents

A method is provided for reducing the amount of wear particulates generated by a total joint orthopaedic implant. The implant consists of two matched articulating components. The method includes the steps of placing the total joint orthopaedic implant in a fluid bath and articulating the implant in the fluid bath for at least 1,000 cycles. The articulation may be performed in three stages. In the first, the implant is articulated under a load of substantially 0.1-500 Newtons with sliding speeds of substantially 0.01-0.5 meters per second. During a second stage the articulation takes place under a ...


Sediment Movement Within A Strip Intercropping System, John E. Gilley, L. A. Kramer, R. M. Cruse, A. Hull Nov 1997

Sediment Movement Within A Strip Intercropping System, John E. Gilley, L. A. Kramer, R. M. Cruse, A. Hull

Biological Systems Engineering: Papers and Publications

This study was conducted to identify sediment movement within a strip intercropping system in southwestern Iowa during the third year of a three-year crop rotation. Soil loss, resulting from the application of simulated rainfall to a Monona silt loam soil, was measured from individual corn (Zea mays L.), soybean (Glycine max (L.) Merr), and winter wheat (Triticum aestivum L.) strips, and from multiple strips which included all three crops. Because of the crop rotation and residue management procedures, used at the study site, a substantial amount of surface cover and vegetative mass was present on each of the strips. As ...


Process For Producing Biodiesel Fuel With Reduced Viscosity And A Cloud Point Below Thirty-Two (32) Degrees Fahrenheit , Hossein Noureddini Oct 1997

Process For Producing Biodiesel Fuel With Reduced Viscosity And A Cloud Point Below Thirty-Two (32) Degrees Fahrenheit , Hossein Noureddini

Papers in Biomaterials

Triglycerides are reacted in a liquid phase reaction with methanol and a homogeneous basic catalyst. The reaction yields a spatially separated two phase result with an upper located non-polar phase consisting principally of non-polar methyl esters and a lower located phase consisting principally of glycerol and residual methyl esters. The glycerol phase is passed through a strong cationic ion exchanger to remove anions, resulting in a neutral product which is flashed to remove methanol and which is reacted with isobutylene in the presence of a strong acid catalyst to produce glycerol ethers. The glycerol ethers are then added back to ...


Electrophysiologic Studies Of Hypothalamic Adenosine-5'-Triphosphate-Sensitive Potassium Channels, Dinora Hernandez Oct 1997

Electrophysiologic Studies Of Hypothalamic Adenosine-5'-Triphosphate-Sensitive Potassium Channels, Dinora Hernandez

Theses

Of particular interest in this study were the electrical phenomena involving currents from the ATP sensitive K channel in isolated hypothalamic ventromedial nucleus (VMN) neurons. These neurons may play an important role in the glucose-sensing system of the body. Rat VMN neurons were isolated. For neuronal isolation, the proteolytic enzyme pronase was used. However, pronase was too harsh. The use of papain, another proteolytic enzyme, led to better neuronal morphology. The perforated patch clamp technique was used to gain access to the cell's interior. For membrane pore formation, nystatin was used; but seal formation was difficult. Amphotericin was used ...


Determination Of Effects Of Stress On Polymeric Ankle-Foot Due To Weight Change: Experimental Stress Analysis, Lin Yu Wang Oct 1997

Determination Of Effects Of Stress On Polymeric Ankle-Foot Due To Weight Change: Experimental Stress Analysis, Lin Yu Wang

Theses

Ankle-Foot Orthoses (AFOs) are devices that assist patients who sustained an abnormal motion at the ankle joint of the foot due to traumatic injury and stroke, etc. The objective of this project is to determine the stress patterns in AFOs under different loading conditions such as weights and genders. Thus, the location of failure can be predicted, and a redesign process can be developed. Furthermore, those experimental results will be used to verify the results obtained from the previous Finite Element Analysis (FEA) [11,10]. Results from the experiment showed a significant stress change due to load change. This stress ...


Using Heart Variability To Measure The Effects Of Manual Medicine On Autonomic Activity, Michael Zullow Oct 1997

Using Heart Variability To Measure The Effects Of Manual Medicine On Autonomic Activity, Michael Zullow

Theses

A pilot study was performed to test the theory that manual medicine techniques known as the CV4 (compression of fourth cerebral ventricle) maneuver and a sacral hold/iliac bridge hold combination increase parasympathetic activity. Manual medicine techniques are widely practiced by Doctors of Osteopathy and Chiropractors to treat physical and mental health problems. Those who have received manual therapy have reported to experience less pain, better mobility, and a greater feeling of relaxation. To help us learn about the effects of manual therapy, autonomic activity was measured scientifically rather than subjectively in this study by monitoring respiration rate and heart ...


Testing Of A Water Loss Distribution Model For Moving Sprinkler Systems, Allen L. Thompson, Derrel L. Martin, John M. Norman, Judy A. Tolk, James R. Gilley, Arlan D. Schneider Sep 1997

Testing Of A Water Loss Distribution Model For Moving Sprinkler Systems, Allen L. Thompson, Derrel L. Martin, John M. Norman, Judy A. Tolk, James R. Gilley, Arlan D. Schneider

Biological Systems Engineering: Papers and Publications

Field water balance measurements using monolithic lysimeters were used in validating the Cupid-DPE model for predicting water loss partitioning during sprinkler irrigation from a moving lateral system fitted with impact sprinklers and spray nozzles. The model combines equations governing water droplet evaporation and droplet ballistics with a comprehensive plant-environment energy balance model. Comparisons indicate good agreement between measured and modeled transpiration, and the measured and modeled soil evaporation during the day of irrigation. Total predicted evapotranspiration during the day of irrigation was greater than measured totals using the monolithic lysimeters. However, part of this difference was because the lysimeters could ...


Runoff, Erosion, And Soil Quality Characteristics Of A Former Conservation Reserve Program Site In Southwestern Oklahoma, John E. Gilley, John W. Doran, Thanh H. Dao Sep 1997

Runoff, Erosion, And Soil Quality Characteristics Of A Former Conservation Reserve Program Site In Southwestern Oklahoma, John E. Gilley, John W. Doran, Thanh H. Dao

Biological Systems Engineering: Papers and Publications

This study was conducted to measure runoff, erosion, and soil quality characteristics of a site in southwestern Oklahoma the first year following conversion from the Conservation Reserve Program (CRP). Treatments included undisturbed CRP, Old World bluestem (Bothriochlora ischaemum L.), no-till wheat (Triticum aestivum L.) and conservation-till wheat. Significant differences in surface cover were found between each of the experimental treatments, with values ranging from 100% on the undisturbed CRP site to 42% for the conservation-till treatment. No significant difference in runoff was found among the various experimental treatments. The Old World bluestem and winter wheat treatments had only minimal erosion ...


Interferon Gamma (Ifn-Gamma) Is Necessary For The Genesis Of Acetylcholine Receptor-Induced Clinical Experimental Autoimmune Myasthenia Gravis In Mice., Balaji Balasa, Caishu Deng, Jae Lee, Linda M. Bradley, Dyanna K. Dalton, Premkumar Christadoss, Nora Sarvetnick Aug 1997

Interferon Gamma (Ifn-Gamma) Is Necessary For The Genesis Of Acetylcholine Receptor-Induced Clinical Experimental Autoimmune Myasthenia Gravis In Mice., Balaji Balasa, Caishu Deng, Jae Lee, Linda M. Bradley, Dyanna K. Dalton, Premkumar Christadoss, Nora Sarvetnick

Journal Articles: Regenerative Medicine

Experimental autoimmune myasthenia gravis (EAMG) is an animal model of human myasthenia gravis (MG). In mice, EAMG is induced by immunization with Torpedo californica acetylcholine receptor (AChR) in complete Freund's adjuvant (CFA). However, the role of cytokines in the pathogenesis of EAMG is not clear. Because EAMG is an antibody-mediated disease, it is of the prevailing notion that Th2 but not Th1 cytokines play a role in the pathogenesis of this disease. To test the hypothesis that the Th1 cytokine, interferon (IFN)-gamma, plays a role in the development of EAMG, we immunized IFN-gamma knockout (IFN-gko) (-/-) mice and wild-type ...


Model Of Flexural Fatigue Damage Accumulation For Cortical Bone, L. V. Griffin, J. C. Gibeling, R. B. Martin, V. A. Gibson, S. M. Stover Jul 1997

Model Of Flexural Fatigue Damage Accumulation For Cortical Bone, L. V. Griffin, J. C. Gibeling, R. B. Martin, V. A. Gibson, S. M. Stover

Biomedical and General Engineering

Analytical models that predict modulus degradation in cortical bone subjected to uniaxial fatigue loading in tension and compression are presented. On the basis of experimental observations, damage was modeled as self-limiting for tension but not for compression. These mechanistic uniaxial damage models were then developed into a model for flexural fatigue of cortical bone based on laminated beam theory. The unknown coefficients in the uniaxial damage models were obtained by successfully fitting the resulting equations to uniaxial fatigue data from the literature on human cortical bone in tension and compression. Then, the predictions of the flexural model for the behavior ...


Laparoscopic Assisted Fusion Of The Lumbosacral Spine: A Biomechanical And Histologic Analysis Of The Open Versus Laparoscopic Technique In An Animal Model, Lee H. Riley Iii, Jason C. Eck, Hiryuki Yoshida, Jeffrey M. Toth, Nguyen Cahn, Tae Hong Lim, Linda M. Mcgrady Jun 1997

Laparoscopic Assisted Fusion Of The Lumbosacral Spine: A Biomechanical And Histologic Analysis Of The Open Versus Laparoscopic Technique In An Animal Model, Lee H. Riley Iii, Jason C. Eck, Hiryuki Yoshida, Jeffrey M. Toth, Nguyen Cahn, Tae Hong Lim, Linda M. Mcgrady

Biomedical Engineering Faculty Research and Publications

Study Design. An animal model for laparoscopic lumbosacral fusion.

Objectives. To compare the biomechanical and histologic results of open to laparoscopic lumbosacral discectomy and fusion in an animal model.

Background Data. Early clinical reports of laparoscopic lumbosacral fusions are encouraging, but animal experiments have not been reported.

Methods. Ten pigs (50-80 kg) were divided into two groups. Group 1 underwent an open anterior lumbosacral discectomy and fusion at L7-S1 using autologous bone graft and a titanium MOSS (DePuy Motech) cage. Group 2 was identical to Group 1 except that a laparoscopic technique was used. The animals were killed at 3 ...


The Evolution Of An Introductory Biological Engineering Course: Design Is The Endpoint!, D. Raj Raman Jun 1997

The Evolution Of An Introductory Biological Engineering Course: Design Is The Endpoint!, D. Raj Raman

D. Raj Raman

Four the past four years, I have taught the sophomore level course, Agricultural Engineering 243 Material and Energy Flows in Biological Systems each spring semester. During the first offering, I used the lecture method to transmit information, and homework assignments and exams to reinforce skills and test comprehension. The greatest weakness of this technique seemed the lack of hands-on experience which I gave my students, and their subsequent lack of physical intuition. Enhancing their physical intuition drove the first curricular revision—using in-class demonstrations and simulations of key physical and biological processes. This technique did not work as well as ...


Experimental Spinal Fusion With Recombinant Human Bone Morphogenetic Protein-2 Without Decortication Of Osseous Elements, Harvinder Sandhu, Linda E.A. Kanim, Jeffrey M. Toth, J. Michael Kabo, David Liu, Rick B. Delamarter, Edgar G. Dawson Jun 1997

Experimental Spinal Fusion With Recombinant Human Bone Morphogenetic Protein-2 Without Decortication Of Osseous Elements, Harvinder Sandhu, Linda E.A. Kanim, Jeffrey M. Toth, J. Michael Kabo, David Liu, Rick B. Delamarter, Edgar G. Dawson

Biomedical Engineering Faculty Research and Publications

Study Design. L4-L5 intertransverse process fusions were produced with 58 μg, 230 μg, or 920 μg of recombinant human bone morphogenetic protein-2 in 20 dogs. Eleven had traditional decortication of posterior elements before insertion of the implant. Nine were left undecorticated. All animals were evaluated 3 months after surgery.

Objectives. To determine whether decortication is a prerequisite for successful fusion in the presence of osteoinductive proteins such as bone morphogenetic protein-2.

Summary of Background Data. Recombinant osteoinductive proteins can induce de novo bone in ectopic soft-tissue sites in the absence of bone marrow elements. Traditional methods for achieving spinal fusion ...


Computer Simulation Of Cerebrovascular Circulation : Assessment Of Intracranial Hemodynamics During Induction Of Anesthesia, Steven D. Wolk May 1997

Computer Simulation Of Cerebrovascular Circulation : Assessment Of Intracranial Hemodynamics During Induction Of Anesthesia, Steven D. Wolk

Theses

The purpose of this project was to develop a computer model of cerebrovascular hemodynamics interacting with a pharmacokinetic drug model to examine the effects of various stimuli during anesthesia on cerebral blood flow and intracranial pressure.


Mechanical Evaluation Of Pedicle Screw Fixation Of The Lumbar Spine, Ding Lu May 1997

Mechanical Evaluation Of Pedicle Screw Fixation Of The Lumbar Spine, Ding Lu

Theses

Pedicle screw fixation of the lumbar spine has been reported to increase fusion rates A biomechanical evaluation of four different pedicle screw implant systems, (AO. Rogozinski, TSRH and Wiltse). was performed to compare intrinsic device stiffness under conditions of flexion-compression and forty-five degree off-axis flexion-compression The effect on stiffness of the loosening of device members was also studied. Testing was done in load control using an electrohvdrualic testing machine. UHMWPe blocks are used to simulate the vertebra.

Assuming that stiffness is directly proportional to the probability of obtaining fusion. this study allows the ranking of the systems tested in their ...


The Relationship Between Thermoregulatory And Haemodynamic Responses Of The Skin To Relaxation And Stress, Paul O. Nketia May 1997

The Relationship Between Thermoregulatory And Haemodynamic Responses Of The Skin To Relaxation And Stress, Paul O. Nketia

Theses

The present study investigated the effects of stress and relaxation on (1) EEG coherence and (2) peripheral blood flow.

EEG coherence of two meditators in two different but adjacent rooms was measured during eyes opened, eyes closed, single meditation and group meditation. The skin temperatures of the subjects together with their room temperatures were also recorded. EEG coherence plots (Cospar) showed a spread out of the alpha band to the beta, theta and occasionally to the delta wave bands during group meditation. The area above the 0.98 coherence threshold in the alpha band was greater during group meditation than ...


Renin-Angiotensin System And Its Relationship To Arterial Pressure Regulation, Sami D. Saume May 1997

Renin-Angiotensin System And Its Relationship To Arterial Pressure Regulation, Sami D. Saume

Theses

The renal system is known to participate in the natural regulation of blood pressure. A renal system model that simulates interaction responses of renal output to arterial blood pressure was developed. The major components of this model are glomerular filtration rate, tubular sodium reabsorption, the renin-angiotensin system, Aldosterone secretion, and antidiuretic hormone secretion. The model's differential equations were coded using Vissim 1.2 student version. It was found that, the renal output increased as glomerular filtration rate, Aldosterone concentration, and blood pressure increased. Conversely, increasing antidiuretic hormone concentration lead to decreased renal output.


Relative Dentifrice Abrasivity On Dentin And Enamel, Laura Marchetti May 1997

Relative Dentifrice Abrasivity On Dentin And Enamel, Laura Marchetti

Theses

The abrasive characteristics of six (6) brands of toothpastes on Enamel and Dentin material were assessed. Human teeth were sliced to expose the dentin surface and then polished using 3 µm and 0.25 µm diamond paste. The outside surface of the tooth (after slicing) was used "as is" for the enamel surface testing. The surface smoothness was evaluated prior to testing using a surface profiler and averaging four (4) to five (5) readings across the surface for each sample.

The tooth slices were then embedded into the acrylic plate surface by routing out an area with a dental drill ...


Determination And Studying Of Stress Distribution In Various Ankle-Foot Orthoses : Experimental Stress Analysis, Rong Feng May 1997

Determination And Studying Of Stress Distribution In Various Ankle-Foot Orthoses : Experimental Stress Analysis, Rong Feng

Theses

Ankle-Foot Orthosis (AFO) is prescribed to constrain and inhibit abnormal motion such as "drop foot" due to stroke. Most orthoses were hand-made by orthotists according to their own experience. However, some types of AFO were easy to fatigue (out of their functional capabilities) than others due to regular usage. In order to improve the design and usage, quantitative stress analysis of different types of orthoses is needed. The objective of this project is to obtain experimental data which will confirm the results obtained from previous Finite Element Analysis (FEA)[1]. In addition, the experimental analysis is extended to obtain more ...


Local Delivery Of Interleukin 4 By Retrovirus-Transduced T Lymphocytes Ameliorates Experimental Autoimmune Encephalomyelitis., Michael K. Shaw, James B. Lorens, Archana Dhawan, Richard Dalcanto, Harley Y. Tse, Alyssa B. Tran, Colleen Bonpane, Shanti L. Eswaran, Stefan Brocke, Nora Sarvetnick, Lawrence Steinman, Garry P. Nolan, C. Garrison Fathman May 1997

Local Delivery Of Interleukin 4 By Retrovirus-Transduced T Lymphocytes Ameliorates Experimental Autoimmune Encephalomyelitis., Michael K. Shaw, James B. Lorens, Archana Dhawan, Richard Dalcanto, Harley Y. Tse, Alyssa B. Tran, Colleen Bonpane, Shanti L. Eswaran, Stefan Brocke, Nora Sarvetnick, Lawrence Steinman, Garry P. Nolan, C. Garrison Fathman

Journal Articles: Regenerative Medicine

Experimental autoimmune encephalomyelitis (EAE) is an inflammatory autoimmune disease of the central nervous system which serves as a model for the human disease multiple sclerosis. We demonstrate here that encephalitogenic T cells, transduced with a retroviral gene, construct to express interleukin 4, and can delay the onset and reduce the severity of EAE when adoptively transferred to myelin basic protein-immunized mice. Thus, T lymphocytes transduced with retroviral vectors can deliver "regulatory cytokines" in a site-specific manner and may represent a viable therapeutic strategy for the treatment of autoimmune disease.


Tillage Effects On Soil Erosion Potential And Soil Quality Of A Former Conservation Reserve Program Site, John E. Gilley, J. W. Doran May 1997

Tillage Effects On Soil Erosion Potential And Soil Quality Of A Former Conservation Reserve Program Site, John E. Gilley, J. W. Doran

Biological Systems Engineering: Papers and Publications

This study was conducted to determine the effects of tillage on soil erosion potential and soil quality characteristics of a former Conservation Research Program (CRP) site. Following tillage, the study area in northern Mississippi was maintained in a fallow condition for nine months. Soil loss from simulated rainfall events was minimal on recently tilled plots and an adjoining, undisturbed CRP area. In contrast, soil loss from the former CRP site which had been tilled nine months previously was similar to values obtained before the CRP program when the area had been cropped for several years. Tillage and over-winter fallowing caused ...


Slice Location Dependence Of Aortic Regurgitation Measurements With Mr Phase Velocity Mapping, George P. Chatzimavroudis, Peter G. Walker, John N. Oshinski, Robert H. Franch, Roderic I. Pettigrew, Ajit P. Yoganathan Apr 1997

Slice Location Dependence Of Aortic Regurgitation Measurements With Mr Phase Velocity Mapping, George P. Chatzimavroudis, Peter G. Walker, John N. Oshinski, Robert H. Franch, Roderic I. Pettigrew, Ajit P. Yoganathan

Chemical & Biomedical Engineering Faculty Publications

Although several methods have been used clinically to assess aortic regurgitation (AR), there is no “gold standard” for regurgitant volume measurement. Magnetic resonance phase velocity mapping (PVM) can be used for noninvasive blood flow measurements. To evaluate the accuracy of PVM in quantifying AR with a single imaging slice in the ascending aorta, in vitro experiments were performed by using a compliant aortic model. Attention was focused on determining the slice location that provided the best results. The most accurate measurements were taken between the aortic valve annulus and the coronary ostia where the measured (Y) and actual (X) flow ...


Glycerolysis Of Fats And Methyl Esters., Hossein Noureddini, V Medikonduru Apr 1997

Glycerolysis Of Fats And Methyl Esters., Hossein Noureddini, V Medikonduru

Papers in Biomaterials

The glycerolysis of methyl esters and triglycerides with crude glycerol. a coproduct from the transesterification of triglycerides, was studied. Three procedures were followed ior this conversion. The first procedure was a one-step glycerolysis with methyl esters. The second procedure was a two-step process. This proced~~irnev olved an initial partial glycerolysis with methyl esters, followed by fat glycerolysis. The third procedure u,as a simultaneous glycerolysis n,ith methyl esters and triglycerides. In the glycerolysis with methyl esters, the removal of methanol is vital to the production of mono- and diglycerides. Methanol was removed either by drawing vacuum on the ...


Monoclonal Antibody Assay And Kit For Detecting Metal Cations In Body Fluids (Continuation), Randall R. Carlson, Jay S. Stout, Dwane E. Wylie, Fred W. Wagner, Malcolm Riddell Apr 1997

Monoclonal Antibody Assay And Kit For Detecting Metal Cations In Body Fluids (Continuation), Randall R. Carlson, Jay S. Stout, Dwane E. Wylie, Fred W. Wagner, Malcolm Riddell

Staff Publications: Biological Process Development Facility

The invention provides method and kits for detecting a metallic cation in a sample of a body fluid. The preferred method and kits include the use of at least two different types of antibodies having different specificities. In the preferred method, the sample of body fluid can be contacted with an effective amount of a capture antibody specific for a naturally occurring polypeptide that can bind the metallic cation to form a first antigen-antibody complex. An effective amount of an antibody specific for an epitope on a metallic cation-naturally occurring polypeptide complex or an antibody specific for a metallic cation ...


Generic, Geometric Finite Element Analysis Of The Transtibial Residual Limb And Prosthetic Socket, Barbara Silver-Thorn, Dudley S. Childress Apr 1997

Generic, Geometric Finite Element Analysis Of The Transtibial Residual Limb And Prosthetic Socket, Barbara Silver-Thorn, Dudley S. Childress

Biomedical Engineering Faculty Research and Publications

Finite element analysis was used to investigate the stress distribution between the residual limb and prosthetic socket of persons with transtibial amputation (TTA). The purpose of this study was to develop a tool to provide a quantitative estimate of prosthetic interface pressures to improve our understanding of residual limb/prosthetic socket biomechanics and prosthetic fit. FE models of the residual limb and prosthetic socket were created. In contrast to previous FE models of the prosthetic socket/residual limb system, these models were not based on the geometry of a particular individual, but instead were based on a generic, geometric approximation ...


Kinetics Of Transesterification Of Soybean Oil, Hossein Noureddini, D Zhu Mar 1997

Kinetics Of Transesterification Of Soybean Oil, Hossein Noureddini, D Zhu

Papers in Biomaterials

Transesterification of soybean oil with methanol was investigated. Three stepwise and reversible reacttons are believed to occur. The effect of variations in mixing intensity (Reynolds number = 3,100 to 12,400) and temperature (30 to 70'CJ on the rate oireaction were studied while the molar ratio of alcohol to triglycerol (6:l) and the concentration of catalyst (0.20 wt% based on soybean oil) were held constant. The variations in mixing intensity appear to effect the reaction parallel to the variations in temperature. A reaction mechanism consisting of an initial mass transfer-controlled region followed by a kinetically controlled region ...


Stiffness Of Measurement System And Significant Figures Of Displacement Which Are Required To Interpret Adhesional Force Curves, Nancy Burnham, Kunio Takahashi, Hubert Pollock, Tadao Onzawa Feb 1997

Stiffness Of Measurement System And Significant Figures Of Displacement Which Are Required To Interpret Adhesional Force Curves, Nancy Burnham, Kunio Takahashi, Hubert Pollock, Tadao Onzawa

Nancy A. Burnham

Force curves obtained from an elastic contact theory are shown and compared with experimental results. In the elastic contact theory, a pin-on-disk contact is assumed and the following interaction are taken into consideration; (i) elastic deformation, (ii) the specific energy of adhesion in the area of the contact, which is expressed as the difference between the surface energies and the interface energy, (iii) the long-range interaction outside the area of contact, assuming the additivity of the Lennard-Jones type potential, and (iv) another elastic term for the measurement system such as the cantilever stiffness of an atomic force microscope (AFM). In ...


Residual Strength Of Equine Bone Is Not Reduced By Intense Fatigue Loading: Implications For Stress Fracture, R. B. Martin, V. A. Gibson, S. M. Stover, J. C. Gibeling, L. V. Griffin Feb 1997

Residual Strength Of Equine Bone Is Not Reduced By Intense Fatigue Loading: Implications For Stress Fracture, R. B. Martin, V. A. Gibson, S. M. Stover, J. C. Gibeling, L. V. Griffin

Biomedical and General Engineering

Fatigue or stress fractures are an important clinical problem in humans as well as racehorses. An important question in this context is, when a bone experiences. fa!igue damage ~uring e~treme use, how much is it weakened compared to its original state? Since there are very ltmtted data on thts quesuon and stress fractures are common in racehorses, we sought to determine the effect of fatigue loading on the monotonic l:trength of equine cortical bone. Beams were machined from the dorsal, medial and lateral cortices of the third metacarpal bones of six thoroughbred racehorses. Beams from left and ...


Ifn-Gamma, Igif, And Iddm., Nora Sarvetnick Feb 1997

Ifn-Gamma, Igif, And Iddm., Nora Sarvetnick

Journal Articles: Regenerative Medicine

No abstract provided.


Alloy Oxidation And Porcelain Fused To Alloy Interaction In Noble Alloy Systems, M. S. Bapna, H. J. Mueller Jan 1997

Alloy Oxidation And Porcelain Fused To Alloy Interaction In Noble Alloy Systems, M. S. Bapna, H. J. Mueller

Cells and Materials

The oxidation and porcelain fusion characteristics of noble alloys containing a variety of minor oxidizable elements, including Cu, Sn, In, Ga, Mn, and Fe were investigated. Four porcelain alloys systems: a Pd-base alloy (Naturelle}, two Pd-Ag-based alloys (Jelstar and Acclaim}, and a high Au-alloy (SMG-3) were examined by scanning electron microscopy and energy dispersive spectroscopy after being heat treated and after being fused with porcelain. Internal oxidation of minor alloying elements occurred within several micrometers from the surface in all four alloys. Surface nodules as detected by other investigators for a Pd-Ag alloy were also detected in this study. Evidence ...