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Articles 1981 - 2010 of 2082

Full-Text Articles in Engineering

Influence Of Mortar Rheology On Aggregate Settlement, Michael F. Petrou, Baolin Wan, Francis Gadala-Maria, Venkata Giri Kolli, Kent A. Harries Jul 2000

Influence Of Mortar Rheology On Aggregate Settlement, Michael F. Petrou, Baolin Wan, Francis Gadala-Maria, Venkata Giri Kolli, Kent A. Harries

Civil and Environmental Engineering Faculty Research and Publications

The influence of the rheology of fresh concrete on the settlement of aggregate is examined. Fresh concrete exhibits a yield stress that, under certain conditions, prevents the settlement of coarse aggregate, although its density is larger than that of the suspending mortar. Calculations, based on estimates of the yield stress obtained from slump tests, predict that aggregate normally used in concrete should not sink. To test this prediction, the settlement of a stone in fresh mortar is monitored. The stone does not sink in the undisturbed mortar (which has a high yield stress), but sinks when the mortar is vibrated, …


A New Approach For Computing The Bandwidth Statistics Of Avalanche Photodiodes, Majeed M. Hayat, Guoquan Dong Jun 2000

A New Approach For Computing The Bandwidth Statistics Of Avalanche Photodiodes, Majeed M. Hayat, Guoquan Dong

Electrical and Computer Engineering Faculty Research and Publications

A new approach for characterizing the avalanche-buildup-time-limited bandwidth of avalanche photodiodes (APDs) is introduced which relies on the direct knowledge of the statistics of the random response time. The random response time is the actual duration of the APD’s finite buildup-limited random impulse response function. A theory is developed characterizing the probability distribution function (PDF) of the random response time. Recurrence equations are derived and numerically solved to yield the PDF of the random response time. The PDF is then used to compute the mean and the standard deviation of the bandwidth. The dependence of the mean and the standard …


Preferences For Permitted And Protected Left-Turn Signal Displays, Alexander Drakopoulos, Richard W. Lyles May 2000

Preferences For Permitted And Protected Left-Turn Signal Displays, Alexander Drakopoulos, Richard W. Lyles

Civil and Environmental Engineering Faculty Research and Publications

Twenty-two different signal displays for permitted and protected left turns were evaluated from a driver comprehension perspective. The objective was to identify which alternate signal displays used to convey the same left-turn message to the driver are better comprehended and therefore recommended for use in the field. Protected displays compliant with the Manual on Uniform Traffic Control Devices were found to be better comprehended than certain noncompliant displays; however, some noncompliant permitted displays were found to outperform their compliant counterparts. Regional comprehension biases are nonexistent for the most part, regardless of display compliance with the Manual on Uniform Traffic Control …


Main Project Report : Noise And Texture On Pcc Pavements, David Kuemmel, Ronald C. Sonntag, James Crovetti, Yosef Becker, John R. Jaeckel, Allex Satanovsky May 2000

Main Project Report : Noise And Texture On Pcc Pavements, David Kuemmel, Ronald C. Sonntag, James Crovetti, Yosef Becker, John R. Jaeckel, Allex Satanovsky

Transportation Research Center: Noise & Texture Studies

This report represents the second phase of a project sponsored by the Wisconsin DOT and the FHWA researching the texture and noise characteristics of Portland cement concrete (PCC) pavements. The team of Marquette University and the HNTB Corporation measured noise, texture and friction of 57 test sites in Colorado, Iowa, Michigan, Minnesota, North Dakota and Wisconsin. During 1997, new test sections were constructed in Wisconsin, including random transverse, skewed and longitudinally tined PCC pavements. Interior and exterior noise was measured on all 57 sites using the Fast Fourier Transform method with a Larson-Davis two channel real time acoustical analyzer. Subjective …


Traffic Responsive Ramp Metering In A Coordinated System, Brian P. Scharles Apr 2000

Traffic Responsive Ramp Metering In A Coordinated System, Brian P. Scharles

Master's Theses (1922-2009) Access restricted to Marquette Campus

Surface transportation in the United States faces a number of problems. Despite the fact that the United States has one of the best roadway systems in the world, the mobility is declining. Inefficient movement of vehicles reduces productivity, wastes energy, increases emissions, and threatens the quality of life we enjoy. Intelligent Transportation Systems (ITS) provide tools that can assist in addressing current surface transportation problems. ITS provides emerging and advanced technologies in the area of communications, information processing, controls and electronics for transportation needs. Implementation of these technologies regains support of transportation agendas, in an attempt to solve today's traffic …


Investigative Study Of The Italgrip System - Noise Analysis, David Kuemmel, John Jaeckel, Alex Satanovsky Mar 2000

Investigative Study Of The Italgrip System - Noise Analysis, David Kuemmel, John Jaeckel, Alex Satanovsky

Transportation Research Center: Noise & Texture Studies

The purpose of this study was to determine if Italgrip is a suitable technique to increase the safety and quality of Wisconsin roadways. The objective of this noise analysis is to identify and quantify any exterior noise impacts of the Italgrip anti-skid surface treatment on PCC pavements. Italgrip is a very thin surface treatment consisting of a two-part polymer resin placed on pavement and covered with re-worked steel slag. Although widely used in Italy, Italgrip has only been available in the United States since 1999.

This study analyzes comparative data from three types of pavement surfaces: untreated transverse tined PCC …


Micro-Ct Image-Derived Metrics Quantify Arterial Wall Distensibility Reduction In A Rat Model Of Pulmonary Hypertension, Roger H. Johnson, Kelly L. Karau, Robert C. Molthen, Steven Thomas Haworth, Christopher A. Dawson Feb 2000

Micro-Ct Image-Derived Metrics Quantify Arterial Wall Distensibility Reduction In A Rat Model Of Pulmonary Hypertension, Roger H. Johnson, Kelly L. Karau, Robert C. Molthen, Steven Thomas Haworth, Christopher A. Dawson

Biomedical Engineering Faculty Research and Publications

We developed methods to quantify arterial structural and mechanical properties in excised rat lungs and applied them to investigate the distensibility decrease accompanying chronic hypoxia-induced pulmonary hypertension. Lungs of control and hypertensive (three weeks 11% O2) animals were excised and a contrast agent introduced before micro-CT imaging with a special purpose scanner. For each lung, four 3D image data sets were obtained, each at a different intra-arterial contrast agent pressure. Vessel segment diameters and lengths were measured at all levels in the arterial tree hierarchy, and these data used to generate features sensitive to distensibility changes. Results indicate …


On The Assessment Of Stability And Patterning Of Speech Movements, Anne Smith, Michael T. Johnson, Clare Mcgillem, Lisa Goffman Feb 2000

On The Assessment Of Stability And Patterning Of Speech Movements, Anne Smith, Michael T. Johnson, Clare Mcgillem, Lisa Goffman

Electrical and Computer Engineering Faculty Research and Publications

Speech requires the control of complex movements of orofacial structures to produce dynamic variations in the vocal tract transfer function. The nature of the underlying motor control processes has traditionally been investigated by employing measures of articulatory movements, including movement amplitude, velocity, and duration, at selected points in time. An alternative approach, first used in the study of limb motion, is to examine the entire movement trajectory over time. A new approach to speech movement trajectory analysis was introduced in earlier work from this laboratory. In this method, trajectories from multiple movement sequences are time- and amplitude-normalized, and the STI …


Public Perceptions Of The Midwest’S Pavements - Introduction, David Kuemmel Jan 2000

Public Perceptions Of The Midwest’S Pavements - Introduction, David Kuemmel

Transportation Research Center: Public Perception of Midwest Pavements

The “Public Perceptions of the Midwest’s Pavements” is the largest survey of public perceptions of satisfaction and improvement policies on rural, two-lane highways ever conducted in the 20th Century in the USA. The project was a Pooled Fund effort undertaken by the Wisconsin DOT and included equal participation of the Iowa and Minnesota DOTs. Approximately 4500 drivers and over 1000 highway segments were surveyed in the three states in all three phases of the project, between 1996 and 2000.

The surveys included improvement policy and construction alternative issues and trade-offs, as well as surveys of beliefs and attitudes of the …


Scene-Based Nonuniformity Correction With Video Sequences And Registration, Russell C. Hardie, Majeed M. Hayat, Earnest Armstrong, Brian Yasuda Jan 2000

Scene-Based Nonuniformity Correction With Video Sequences And Registration, Russell C. Hardie, Majeed M. Hayat, Earnest Armstrong, Brian Yasuda

Electrical and Computer Engineering Faculty Research and Publications

We describe a new, to our knowledge, scene-based nonuniformity correction algorithm for array detectors. The algorithm relies on the ability to register a sequence of observed frames in the presence of the fixed-pattern noise caused by pixel-to-pixel nonuniformity. In low-to-moderate levels of nonuniformity, sufficiently accurate registration may be possible with standard scene-based registration techniques. If the registration is accurate, and motion exists between the frames, then groups of independent detectors can be identified that observe the same irradiance (or true scene value). These detector outputs are averaged to generate estimates of the true scene values. With these scene estimates, and …


Stochastic Stability Of The Continuous-Time Extended Kalman Filter, K. Reif, S. Gunther, Edwin E. Yaz, R. Unbehauen Jan 2000

Stochastic Stability Of The Continuous-Time Extended Kalman Filter, K. Reif, S. Gunther, Edwin E. Yaz, R. Unbehauen

Electrical and Computer Engineering Faculty Research and Publications

he error behaviour of the extended Kalman filter is analysed. It is proved that the estimation error remains bounded if the system satisfies a detectability condition and both the initial estimation error and the disturbing noise terms are small enough. Moreover, some selected cases with both bounded and unbounded estimation error are demonstrated by numerical simulations.


Control Strategies For The Transition From Multijoint To Single-Joint Arm Movements Studied Using A Simple Mechanical Constraint, Robert A. Scheidt, W. Zev Rymer Jan 2000

Control Strategies For The Transition From Multijoint To Single-Joint Arm Movements Studied Using A Simple Mechanical Constraint, Robert A. Scheidt, W. Zev Rymer

Biomedical Engineering Faculty Research and Publications

Changes were studied in neuromotor control that were evoked by constraining the motion of the elbow joint during planar, supported movements of the dominant arm in eight normal human subjects. Electromyograph (EMG) recordings from shoulder and arm muscles were used to determine whether the normal multijoint muscle activity patterns associated with reaching to a visual target were modified when the movement was reduced to a single-joint task, by pinning the elbow to a particular location in the planar work space. Three blocks of 150 movements each were used in the experiments. Subjects were presented with the unconstrained task in the …


Public Perceptions Of The Midwest’S Pavements - Iowa - Phase Ii (State Wide Survey Report), Marquette University Research Team, Transportation Research Center Dec 1999

Public Perceptions Of The Midwest’S Pavements - Iowa - Phase Ii (State Wide Survey Report), Marquette University Research Team, Transportation Research Center

Transportation Research Center: Public Perception of Midwest Pavements

This report covers Phase II of a three-phase pooled-fund project in Wisconsin, Iowa and Minnesota, to determine the perception/satisfaction levels of the driving public and how they correlate with the states’ physical data bases used to determine priorities for pavement improvements on rural, two-lane highways. In addition, policy issues of trust and improvement trade-offs are addressed.

In Phase I, six focus groups were conducted in each state to determine the beliefs and issues about pavements that could be used to draft statewide questionnaires. Focus groups were held during the last half of 1996 in all three states. From the focus …


3d Micro-Ct For Functional Genomics, R. H. Johnson, Robert C. Molthen, Christopher C. Hanger, Kelly Lynn Karau, Steven Haworth, Christopher Dawson Nov 1999

3d Micro-Ct For Functional Genomics, R. H. Johnson, Robert C. Molthen, Christopher C. Hanger, Kelly Lynn Karau, Steven Haworth, Christopher Dawson

Biomedical Engineering Faculty Research and Publications

No abstract provided.


Investigation Of Feasible Pavement Design Alternatives For Wisdot, James Crovetti, Sam Owusu-Ababio Nov 1999

Investigation Of Feasible Pavement Design Alternatives For Wisdot, James Crovetti, Sam Owusu-Ababio

Transportation Research Center: Feasible Pavement Design Alternatives

The current pavement design and selection process of WisDOT for all new pavements or reconstructions of existing pavement structures provides for the design of one asphaltic concrete (AC) and one portland cement concrete (PCC) pavement alternative. Life-cycle costs analyses are then used to determine the preferred alternative for construction. Previous restrictions in the WisDOT pavement selection process have essentially excluded the construction of thick AC (AC thickness > 150 mm) and thin PCC (PCC thickness < 225 mm) pavements and thus the validity of current life-cycle cost inputs for these pavement types is under question.

This report presents a performance analysis of existing thick AC and thin PCC pavements constructed in and around Wisconsin. The performance trends developed indicate current design …


Theory Of Photon Coincidence Statistics In Photon-Correlated Beams, Majeed M. Hayat, Sergio N. Torres, Leno M. Pedrotti Oct 1999

Theory Of Photon Coincidence Statistics In Photon-Correlated Beams, Majeed M. Hayat, Sergio N. Torres, Leno M. Pedrotti

Electrical and Computer Engineering Faculty Research and Publications

The statistics of photon coincidence counting in photon-correlated beams is thoroughly investigated considering the effect of the finite coincidence resolving time. The correlated beams are assumed to be generated using parametric downconversion, and the photon streams in the correlated beams are modeled by two partially correlated Poisson point processes. An exact expression for the mean rate of coincidence registration is developed using techniques from renewal theory. It is shown that the use of the traditional approximate rate, in certain situations, leads to the overestimation of the actual rate. The error between the exact and approximate coincidence rates increases as the …


Quantification Of Pulmonary Arterial Wall Distensibility Using Parameters Extracted From Volumetric Micro-Ct Images, Roger H. Johnson, Kelly Lynn Karau, Robert C. Molthen, Christopher A. Dawson Sep 1999

Quantification Of Pulmonary Arterial Wall Distensibility Using Parameters Extracted From Volumetric Micro-Ct Images, Roger H. Johnson, Kelly Lynn Karau, Robert C. Molthen, Christopher A. Dawson

Biomedical Engineering Faculty Research and Publications

Stiffening, or loss of distensibility, of arterial vessel walls is among the manifestations of a number of vascular diseases including pulmonary arterial hypertension. We are attempting to quantify the mechanical properties of vessel walls of the pulmonary arterial tree using parameters derived from high-resolution volumetric x-ray CT images of rat lungs. The pulmonary arterial trees of the excised lungs are filled with a contrast agent. The lungs are imaged with arterial pressures spanning the physiological range. Vessel segment diameters are measured from the inlet to the periphery, and distensibilities calculated from diameters as a function of pressure. The method shows …


Cost Effective Concrete Pavement Cross Sections - Interim Report, James Crovetti Aug 1999

Cost Effective Concrete Pavement Cross Sections - Interim Report, James Crovetti

Transportation Reports with the Wisconsin Department of Transportation

The present pavement selection policy of the Wisconsin Department of Transportation (WisDOT) limits the design alternatives for Portland Cement Concrete (PCC) pavements and inhibits the designer's ability to select cross-sections deviating from uniform slab thicknesses with doweled transverse joints. Currently, uniform slab thicknesses and conventional joint load transfer devices are incorporated into the design based on the heavy truck traffic in the outer lane. While this strategy provides for adequate pavement structure in this truck lane to limit faulting and slab cracking to tolerable levels, there is a potential for over-design in other traffic lanes which receive significantly lower Equivalent …


Anatomy Of Soft Tissues Of The Spinal Canal, Hogan Quinn, Jeffrey M. Toth Jul 1999

Anatomy Of Soft Tissues Of The Spinal Canal, Hogan Quinn, Jeffrey M. Toth

Biomedical Engineering Faculty Research and Publications

Background and Objectives.

Important issues regarding the spread of solutions in the epidural space and the anatomy of the site of action of spinal and epidural injections are unresolved. However, the detailed anatomy of the spinal canal has been incompletely determined. We therefore examined the microscopic anatomy of the spinal canal soft tissues, including relationships to the canal walls.

Methods.

Whole mounts were prepared of decalcified vertebral columns with undisturbed contents from three adult humans. Similar material was prepared from a macaque and baboon immediately on death to control for artifact of tissue change after death. Other tissues examined included …


An Analytical Approximation For The Excess Noise Factor Of Avalanche Photodiodes With Dead Space, Majeed M. Hayat, Zikuan Chen, Mohammad Rezaul Karim Jul 1999

An Analytical Approximation For The Excess Noise Factor Of Avalanche Photodiodes With Dead Space, Majeed M. Hayat, Zikuan Chen, Mohammad Rezaul Karim

Electrical and Computer Engineering Faculty Research and Publications

Approximate analytical expressions are derived for the mean gain and the excess noise factor of avalanche photodiodes including the effect of dead space. The analysis is based on undertaking a characteristic-equation approach to obtain an approximate analytical solution to the existing system of recurrence equations which characterize the statistics of the random multiplication gain. The analytical expressions for the excess noise factor and the mean gain are shown to be in good agreement with the exact results obtained from numerical solutions of the recurrence equations for values of the dead space reaching up to 20% of the width of the …


Detection Of Changes In Lung Tissue Properties With Multiple-Indicator Dilution, David L. Roerig, Said H. Audi, John H. Linehan, Gary S. Krenz, S. B. Ahlf, W. Lin, Christopher A. Dawson Jun 1999

Detection Of Changes In Lung Tissue Properties With Multiple-Indicator Dilution, David L. Roerig, Said H. Audi, John H. Linehan, Gary S. Krenz, S. B. Ahlf, W. Lin, Christopher A. Dawson

Biomedical Engineering Faculty Research and Publications

We evaluated the potential utility of a group of indicators, each of which targets a particular tissue property, as indicators in the multiple-indicator dilution method to detect and to identify abnormalities in lung tissue properties resulting from lung injury models. We measured the pulmonary venous outflow concentration vs. time curves of [14C]diazepam, 3HOH, [14C]phenylethylamine, and a vascular reference indicator following their bolus injection into the pulmonary artery of isolated perfused rabbit lungs under different experimental conditions, resulting in changes in the lung tissue composition. The conditions included granulomatous inflammation, induced by the intravenous injection of …


The Use Of Recombinant Human Bone Morphogenetic Protein 2 (Rhbmp-2) To Promote Spinal Fusion In A Nonhuman Primate Anterior Interbody Fusion Model, Brian P. Hecht, Jeffrey S. Fischgrund, Harry N. Harkowitz, Lori Penman, Jeffrey M. Toth, Ali Shirkhoda Apr 1999

The Use Of Recombinant Human Bone Morphogenetic Protein 2 (Rhbmp-2) To Promote Spinal Fusion In A Nonhuman Primate Anterior Interbody Fusion Model, Brian P. Hecht, Jeffrey S. Fischgrund, Harry N. Harkowitz, Lori Penman, Jeffrey M. Toth, Ali Shirkhoda

Biomedical Engineering Faculty Research and Publications

Study Design. A study on the efficacy of recombinant human bone morphogenetic protein 2 (rhBMP-2) in a nonhuman primate anterior interbody fusion model.

Objectives. To investigate the efficacy of rhBMP-2 with an absorbable collagen sponge carrier to promote spinal fusion in a nonhuman primate anterior interbody fusion model.

Summary of Background Data. RhBMP-2 is an osteoinductive growth factor capable of inducing new bone formation in vivo. Although dosage studies using rhBMP-2 have been performed on species of lower phylogenetic level, they cannot be extrapolated to the primate. Dosage studies on nonhuman primates are essential before proceeding with human primate application. …


An Iterative Approach To The Beam Hardening Correction In Cone Beam Ct (Proceedings), Jiang Hsieh, Robert C. Molthen, Christopher A. Dawson, Roger H. Johnson Jan 1999

An Iterative Approach To The Beam Hardening Correction In Cone Beam Ct (Proceedings), Jiang Hsieh, Robert C. Molthen, Christopher A. Dawson, Roger H. Johnson

Biomedical Engineering Faculty Research and Publications

No abstract provided.


Reduction Of Quantum Noise In Transmittance Estimation Using Photonecorrelated Beams, Majeed M. Hayat, Adel Joobeur, Bahaa E.A. Saleh Jan 1999

Reduction Of Quantum Noise In Transmittance Estimation Using Photonecorrelated Beams, Majeed M. Hayat, Adel Joobeur, Bahaa E.A. Saleh

Electrical and Computer Engineering Faculty Research and Publications

The accuracy of optical measurements at low light levels is limited by the quantum noise of the source and by the random nature of the interaction with the measured object. The source noise may be reduced by use of nonclassical photon-number squeezed light. This paper considers the use of two photon-correlated beams (generated, for example, by spontaneous parametric downconversion) to measure the optical transmittance of an object. The photons of each beam obey a random Poisson process, but are synchronized in time. One beam is used to probe the object while the other is used as a reference providing information …


Efficacy Of Beam-Hardening Correction For Vascular Morphometry Using 3d Conebeam Micro-Ct, Roger H. Johnson, Jiang Hsieh, Robert C. Molthen, Christopher A. Dawson Jan 1999

Efficacy Of Beam-Hardening Correction For Vascular Morphometry Using 3d Conebeam Micro-Ct, Roger H. Johnson, Jiang Hsieh, Robert C. Molthen, Christopher A. Dawson

Biomedical Engineering Faculty Research and Publications

No abstract provided.


Pulmonary Disposition Of Lipophilic Amine Compounds In The Isolated Perfused Rabbit Lung, Said H. Audi, Christopher A. Dawson, John H. Linehan, Gary S. Krenz, S. B. Ahlf, David L. Roerig Feb 1998

Pulmonary Disposition Of Lipophilic Amine Compounds In The Isolated Perfused Rabbit Lung, Said H. Audi, Christopher A. Dawson, John H. Linehan, Gary S. Krenz, S. B. Ahlf, David L. Roerig

Biomedical Engineering Faculty Research and Publications

We measured the pulmonary venous concentration vs. time curves for [3H]alfentanil, [14C]lidocaine, and [3H]codeine after the bolus injection of each of these lipophilic amine compounds (LAC) and a vascular-reference indicator (fluorescein isothiocyanate-dextran) into the pulmonary artery of isolated perfused rabbit lungs. A range of flows and perfusate albumin concentrations was studied. To evaluate the information content of the data, we developed a kinetic model describing the pulmonary disposition of these LAC that was based on indicator dilution theory, and we sought a robust approach for interpreting the estimated model parameters. We found that the …


Sensory Changes In Adults With Unilateral Transtibial Amputation, Judith B. Kosasih, Barbara Silver-Thorn Jan 1998

Sensory Changes In Adults With Unilateral Transtibial Amputation, Judith B. Kosasih, Barbara Silver-Thorn

Biomedical Engineering Faculty Research and Publications

The purpose of this study was to describe the sensory changes in adults with unilateral transtibial amputation

(TTA), as any loss of sensation may have significant impact on the successful use of a prosthesis. Sensory modalities of light touch, deep pressure, vibration, and superficial pain (pinprick) were examined on the residual and contralateral limbs of 16 veterans with TTA. Six subjects demonstrated normal sensation on the contralateral limb and impaired sensation of superficial pain, vibration, and/or light touch on the residual limb. Superficial pain was the most frequently impaired sensation, and vibration and superficial pain sensation appeared to be age-dependent, …


Water Transport And The Distribution Of Aquaporin-1 In Pulmonary Air Spaces, Richard M. Effros, C. Darin, Elizabeth R. Jacobs, R. A. Rogers, Gary S. Krenz, E. E. Schneeberger Sep 1997

Water Transport And The Distribution Of Aquaporin-1 In Pulmonary Air Spaces, Richard M. Effros, C. Darin, Elizabeth R. Jacobs, R. A. Rogers, Gary S. Krenz, E. E. Schneeberger

Biomedical Engineering Faculty Research and Publications

Recent evidence suggests that water transport between the pulmonary vasculature and air spaces can be inhibited by HgCl2, an agent that inhibits water channels (aquaporin-1 and -5) of cell membranes. In the present study of isolated rat lungs, clearances of labeled (3HOH) and unlabeled water were compared after instillation of hypotonic or hypertonic solutions into the air spaces or injection of a hypotonic bolus into the pulmonary artery. The clearance of 3HOH between the air spaces and perfusate after intratracheal instillation and from the vasculature to the tissues after pulmonary arterial injections was invariably greater …


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 …


Fostering Strong Interactions Between Industry And Academia, T. R. Kurfess, Mark L. Nagurka Jun 1997

Fostering Strong Interactions Between Industry And Academia, T. R. Kurfess, Mark L. Nagurka

Mechanical Engineering Faculty Research and Publications

This paper highlights a number of key issues in the development and execution of joint university-industry engineering projects. Government funding reductions have lead to decreased support of university research and economic forces have driven corporations to reduce or eliminate internal R&D centers. These are two driving factors behind the renewed ties between universities and industries. In developing a plan for a joint research project and when working together towards its solution, both sides need to be cognizant of their respective roles to ensure a successful partnership.