Biomedical Engineering and Bioengineering Commons^™

In Vitro Activities Of 2,2'-Bipyridyl Analogs Against Mycobacterium Leprae, Arvind Madhav Dhople, Maria Antonia Ibáñez, Anita A. Dhople

Biomedical Engineering and Sciences Faculty Publications

In vitro susceptibility of Mycobacterium leprae to two bipyridyl analogs was studied by using two biochemical parameters to measure the metabolic activity of the organism. VUF-8514 at 0.16 μg/ml, but not VUF-8842, completely inhibited the metabolic activity of M. leprae, and the action was bactericidal. When compared to rifampin (MIC 0.3 μg/ml), VUF-8514 was equally bactericidal against M. leprae.

Experimental Definition For Implantation Of The Afit Cortical Multielectrode Array, Adam G. Spenik

Theses and Dissertations

A two-dimensional multiplexed array of 256 electrodes (16 x 16) has been fabricated using conventional CMOS fabrication techniques. The size and spacing of the electrodes (160 x 160 µm squares with center-to-center spacing of 250 µm) approximate that of the cortical columns. The device is mounted on a small biocompatible package and a protocol to implant this package on the visual cortex of a ferret and a Rhesus monkey was developed and approved. An instrumentation setup to record the data from the device is described as well as the methods used to demultiplex the data. Testing of the device in …

Development Of A Mammographic Image Processing Environment Using Matlab, John L. Kelley

Theses and Dissertations

Breast cancer is a disease that accounts for a disturbingly large number of deaths in females each year. Its prevalence is a topic of concern to all of us since it can affect our families, friends, and coworkers. Although mammographic screening is the most effective method currently available for the early detection of breast cancer, it is far from being an infallible procedure. Mammographic reading is error prone, partly because of the complexity of the task and partly because of the variability in human performance. Computers offer high reproducibility, and when used as an adjunct by the radiologist, may improve …

Computer-Aided Breast Cancer Diagnosis, Catherine M. Kocur

Theses and Dissertations

This research advances computer-aided breast cancer diagnosis. More than 50 million women over the age of 40 are currently at risk from this disease in the United States. Computer-aided diagnosis is offered as a second opinion to radiologists to aid in decreasing the number of false readings of mammograms. This automated tool is designed to enhance detection and classification. New feature extraction methods are presented that provide increased classification power. Angular second moment, a second-order gray-level histogram statistic, provides baseline accuracy. Two novel extraction methods, eigenmass and wavelets, are introduced to the field. Based on the Karhunen-Loeve Transform, eigenmass features …

Characterization And Redesign Of The Afit Multielectrode Array, Richard G. Darenberg Jr.

Theses and Dissertations

Since 1978, faculty and graduate students from the Air Force Institute of Technology (AFIT) have been working on an implantable circuit array that can record visual signals from the brain or stimulate the brain. In the current design the circuit is a 16 x 16 array of pads, each pad being 160 x 160 micrometers with 250 micrometers spacing with an 'L' shaped reference pad used as a ground reference. The array is multiplexed so that only one I-O line is required to access all 256 pads. This research was twofold: first to analyze the existing circuit and identify sources …

A Prototype Computational Phantom To Create Digital Images For Research And Training In Diagnostic Radiology, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Working Papers

Research in the processing, compression, transmission, and interpretation of digital radiographic images require the testing and evaluation of a wide variety of images, varying both in format and in spatial resolution. If receiver operating characteristic (ROC) analysis or a related method is used to evaluate the performance of observers using novel vs. conventional displays, large numbers of test images containing known abnormalities are required. This report describes a convenient, inexpensive, and reproducible source of test images, having any desired resolution and containing precisely defined abnormalities of unlimited subtlety. The images are generated by computing x-ray transmission through mathematically defined, three …

Autonomic Nervous System Evaluation Using Time-Frequency Analysis, Sanjay Fernando

Theses

Spectral analysis of heartrate variability (HRV) provided an estimate of the sympathetic and parasympatheticinfluences on heart rate without drugs or other invasive procedures.However, there are many situations where heart rate changed rapidlyover time and the control of those changes was of considerable interest.Time-frequency analysis was utilized to expand the concept of spectralanalysis of HRV to describe changes in vagal tone and sympatho-vagalbalance as a function of time. As a result the assessment of the autonomicnervous system during rapid changes in heart rate was made.

There were three advantagesto calculating vagal tone and sympatho-vagal balance by using timefrequencyanalysis. First, vagal tone …

Characterization Of Sleep Eeg, Seetharamiah Sateesh

Theses

The physiological relationship between the various components of sleep and its variation due to drug administration has been used as one of the primary tools to analyze the performance of drug. A number of studies have been performed in recent years in this direction. Electroencephalogram (EEG) has been characterized with the help of variables ranging from measurements of the duration of different sleep stages to the activities that define the stages themselves. Advances in computer hardware and software have improved the methods of data acquisition and storage. Analysis of long stretch of data has always been a problem considering the …

Correlation Between Tidal Volume Measured By Spirometry And Impedance Pneumography, Krithika Seshadri

Theses

In this study, an alternative method, impedance pneumography was used to measure the respiration volume. The respiration volume was measured both by using a conventional spirometer and an impedance pneumograph, and evaluated quantitatively in 17 subjects using linear and nonlinear regression algorithms.

Data were collected from 17 normal, healthy subjects during rest and paced breathing conditions. A technique was developed to measure tidal volume by impedance pneumography. The respiration volume measured by the spirometer was correlated with the volume measured by the pneumograph. Different electrode positions and postures were included in the study to determine the position and posture which …

Cervical Spine Bone Anchoring System Csbas Pullout Testing And Comparisons, Konstantin Caploon

Theses

The purpose of this study is to prove the effectiveness of the newly designed and patented Cervical Spine Bone Anchoring System (CSBAS). It is a posterior fixation device intended to be used with spine bone-plate systems. Its purposes are to substitute for conventional bone screws, significantly decrease the neurological and vascular risks associated with screws, and have comparable bone purchase strength.

Three CSBAS sizes (10mm, 12mm, and 14mm) were compared to four conventional bone screws in six human cadaveric cervical spines (C2-C7). Post-implantation axial pullout tests of each device using an MTS servohydraulic testing machine yielded bone purchase strength.

In …

Computerized Scoring Of Sleep Stage Data, Subbarao Narayana

Theses

Sleep is a non-uniform biological state which has been subdivided into different stages. The basic criteria behind staging are the amplitude and frequency variations of sleep data. The sleep analysis is carried out by considering the characteristic variation of all three EEG, EOG and EMG signals. The polygraphic recording of nocturnal sleep is a method of research widely used in neurophysiology laboratories, both for the clinical study of sleep and for the evaluation of the therapeutic effectiveness of drugs acting on sleep. The analysis of this method is carried out by an expert individual whose depth of knowledge regarding the …

High Shear Mixing Reactor For Glycerolysis, Hossein Noureddini

Papers in Biomaterials

lnrcreasEd ervironmental awareness and depletion of resources are driving industry to develop aiternative fuels from renew ble resources that are environmentally more acceprable. Esters of fatty acids (biodiesel)-derived from the traiisesterification of vegetable oils, have properties 3imi:ar to cornponents of petrolium based dieselfuel. Cost has been a Cost has been major factor inslowing down the commercialization of biodiesel. In order to improve the eiuIlulliy ui Illis process two iactors wcrc invcarigated in this study: 1) use of beef tallow as raw mzlerial and 2) by-product utilization. Glycerol is the by-product of the esterlficatiun Drocesg In this work the feasibility of …

Maximum Surface Storage Provided By Crop Residue, John E. Gilley, Eugene R. Kottwitz

Biological Systems Engineering: Papers and Publications

Small ponds created by crop residue serve to store water on upland areas. The present study is conducted to identify the maximum surface storage provided by crop residue. Equations for estimating surface storage are derived assuming that residue elements were oriented end to end, at uniform intervals, in a direction perpendicular to flow. Separate equations are developed for conditions where average slope was greater than or equal to residue cover, or less than residue cover. Both equations relate average surface-storage depth to residue cover, residue diameter, and average slope. Data to test the reliability of the equations are obtained in …

Hydraulic Conditions Required To Move Unanchored Residue Materials, John E. Gilley, E. R. Kottwitz, G. A. Wieman

Biological Systems Engineering: Papers and Publications

Hydraulic conditions required to initiate movement of unanchored residue materials are identified in the present study. Selected amounts of corn, cotton, pine needles, sorghum, soybean, sunflower, and wheat residue are placed in a flume on a sand surface, and flow is then introduced at the top of the flume in progressive increments. The discharge rate and flow velocity necessary to cause residue movement are determined. The ratio of critical flow depth to residue diameter, critical Reynolds number, critical shear stress, dimensionless shear stress, and boundary Reynolds number are calculated from hydraulic measurements. Regression equations are developed to relate dimensionless shear …

Derivation Of Respiration From Electrocardiogram During Heart Rate Variability Studies, Lingeng Zhao

Theses

A method was developed to derive the respiration signal from the ECG signal based on the observation that the body-surface ECG is influenced by electrode motion relative to the heart and that fluctuations in the mean cardiac electrical axis accompany respiration. S-Plus programs were developed to calculate the changes in the value of the mean cardiac electrical axis during respiration from a two lead ECG signal and to generate a continuous ECG-derived respiratory signal from the angle information.

Data were taken from 9 healthy subjects during rest, paced breathing and exercise. The respiration was derived from the recorded ECG signals. …

Modeling, Simulation And Hemodynamic Response Analysis Of Arteriovenous Malformation Occlusion, Huijuan Mao

Theses

The cerebral Arteriovenous Malformation system (AVM) or fistula, is a network with large caliber vessels that yields an alternate pathway for blood flow between arteries and veins. Neurosurgical and interventional radiological techniques are the common way to treat AVM patients so that the normal capillary blood flow would be restored. Several patients who underwent this procedure had different degrees of brain swelling and subsequent hemorrhage. To understand this, Blesser et al. developed a simplified model to simulate the effect of AVM occlusion on cerebrovascular pressure and flow. Their model does not include the cerebrovascular regulatory mechanism which is an important …

3-D Reconstruction And Morphological Analysis Of Normal Rectum, Saritha Sundaresan

Theses

There is no documentation of the 3-D dimensions of normal rectum. We present a method for the architectural and volumetric analysis of the rectum which makes use of a computerized 3-D reconstruction and CT scans of cross-sections of the rectum. The technique is simple, fast, yet potentially reliable. An attempt has been made to calculate the volume, area and average diameter of non-distended rectums (normal). Once we can standardize the technique, then we can study dimensions of the rectum in adult males and females. This thesis constitutes a unified presentation of the essential aspects of the method used in this …

Non‐Rayleigh Statistics Of Ultrasonic Backscattered Echo From Tissues, V. Manjo Narayanan, Robert C. Molthen, P. M. Shankar, J. M. Reid

Biomedical Engineering Faculty Research and Publications

The envelope of the backscattered signal from tissues can exhibit non‐Rayleigh statistics if the number density of scatterers is small or if the variations in the scattering cross sections are random. The K distribution which has been used extensively in radar, is introduced to model this non‐Rayleigh behavior. The generalized K distribution is extremely useful since it encompasses a wide range of distributions such as Rayleigh, Lognormal, and Rician. Computer simulations were conducted using a simple one‐dimensional discrete scatteringmodel to investigate the properties of the echo envelope. In addition to cases of low number densities, significant departures from Rayleigh statistics …

Production Of Interleukin 10 By Islet Cells Accelerates Immune-Mediated Destruction Of Beta Cells In Nonobese Diabetic Mice., Lise Wogensen, Myung-Shik Lee, Nora Sarvetnick

Journal Articles: Regenerative Medicine

The T helper type 2 (Th2) cell product interleukin 10 (IL-10) inhibits the proliferation and function of Th1 lymphocytes and macrophages (M phi). The nonobese diabetic mouse strain (NOD/Shi) develops a M phi and T cell-dependent autoimmune diabetes that closely resembles human insulin-dependent diabetes mellitus (IDDM). The objective of the present study was to explore the consequences of localized production of IL-10 on diabetes development in NOD/Shi mice. Surprisingly, local production of IL-10 accelerated the onset and increased the prevalence of diabetes, since diabetes developed at 5-10 wk of age in 92% of IL-10 positive I-A beta g7/g7, I-E- mice …

Laser Assisted Pd Seeding For Electroless Plating On Siq2, A. G. Schrott, B. Braren, Ravi F. Saraf

Ravi Saraf Publications

Excimer laser pulses with wavelengths of 248 and 308 nm were used to selectively seed Pd on SiO₂ surfaces, making them suitable for electroless plating. This novel seeding process for insulating materials is accomplished with the sample immersed in the seeding solution, and occurs only on the areas of the substrate that are illuminated (through the liquid) by the laser light. The Pd content of the seeded samples increased with the number of pulses, but was rather independent of repetition rate. The deposition rate showed a dependence with wavelength consistent with a defect driven mechanism for electron excitation through …

Overview Of Federal Technology Transfer, Lawrence Rudolph

RISK: Health, Safety & Environment (1990-2002)

Mr. Rudolph reviews approximately thirteen years of legal and political developments that have contributed to laws governing the extent to which private firms may secure rights in technology at least partly developed with federal funds.

Pancreatic Islet Production Of Murine Interleukin-10 Does Not Inhibit Immune-Mediated Tissue Destruction., Myung-Shik Lee, Lise Wogensen, Judith Shizuru, Michael B.A. Oldstone, Nora Sarvetnick

Journal Articles: Regenerative Medicine

IL-10 inhibits macrophage-dependent antigen presentation, cytokine production, and generation of allospecific cells in vitro. These findings have lead to the widespread expectation that IL-10 may be a useful immunosuppressive agent to inhibit allograft rejection or autoimmunity in vivo. We used two experimental paradigms to study effects of murine IL-10 on in vivo immune responses. First, fetal pancreata or adult pancreatic islets from transgenic mice expressing IL-10 in pancreatic beta cells (Ins-IL-10 mice) were grafted across the MHC barrier to examine if IL-10 could inhibit allograft rejection. Second, Ins-IL-10 mice were crossed with transgenic mice expressing lymphocytic choriomeningitis virus (LCMV) antigens …

Technology Transfer: A View From The Trenches, Harvey Drucker

RISK: Health, Safety & Environment (1990-2002)

Dr. Drucker, who has lab-wide responsibility for technology transfer at Argonne National Laboratory, argues that transferring rights in discoveries made through tax supported research to private entities can contribute to public welfare in many ways.

The Prediction Of Pilot Opinion Ratings Using Optimal And Sub-Optimal Pilot Models, Craig R. Edkins

Theses and Dissertations

This study details the development of a sub-optimal pilot model that blended the classical and optimal pilot model approaches in an attempt to achieve the advantages of each. This model used a numerical solution to the linear quadratic Gaussian problem to find the pilot gain, lead, and lag values that minimized a performance index consisting of task error and control usage. This development was conducted in four phases. First, an optimal pilot model developed by Systems Technology, Incorporated, was analyzed in detail. This analysis included a step-by-step example problem to clarify the model's logic and an in-depth sensitivity analysis of …

Patient, Disease And Surgical Parameters In The Prediction Of Histologic Nodes And Recurrence Of Squamous Cell Carcinoma, Adolfo A. Ferreira

Theses

This research explores the impact of a variety patient, disease and lesion parameters upon the probability of post surgery recurrence of squamous cell carcinoma and the involvement of histologic nodes. It was found that parameters such as number of nodes, Lymph Vascular Space Invasion (LVS), figo stage, growth rate and host response as well as tumor thickness, depth of invasion and lesion size are good predictors. Other parameters such as cell type and condylomas were found to correlate minimally with recurrence and histologic nodes. Surgical parameters such as surgical margin and distance surgical margin were found to have poor correlation …

Time Frequency Analysis Of The Electromyogram During Fatigue, Michelle Rene Davies

Theses

Spectral parameters obtained from the surface EMG signal have been used as indicators of fatigue during a sustained contraction. These same parameters have not been tested with the EMG signals obtained from fine wire electrodes. One such parameter is the median frequency which is known to decline with fatigue. A comparison was done between the median frequencies obtained from the surface EMG and those obtained from the fine wire EMG. The median frequencies from both types of electrodes decreased with time indicating that fine wire electrodes could be used to measure fatigue.

In addition, a new technique, time frequency analysis, …

Three Dimensional Diaphragm Simulation Model For The Relationship Of The Tension, Pressure And Shape, Zhangming He

Theses

Weakness of inspiratory muscles is a major cause of respiratory failure. There are many clinical circumstances in which it may occur. The diaphragm is a major respiratory muscle. It has been difficult to quantify its shape, curvature and length.

To solve this question, a three dimensional diaphragm equation was derived on the, assumption that the diaphragm is only attached at its periphery to the rib cage and the abdomen is filled with fluid. Computer programs were developed to fit the equation to the diaphragm contours obtained from plane X rays.

The results indicate that the ratio of transdiaphragmatic pressure to …

In Vitro Testing And Evaluation Of Intraaortic And Extraaortic Balloon Counterpulsation Devices, Joseph V. Izzo

Theses

The primary purpose of this project was to develop an in vitro environment in which the intraaortic and extra-aortic balloon pumps could be tested and evaluated. This was done by modifying a mechanical heart simulator -- the pulse duplicator system -- to accommodate both devices, and developing a software system that could collect and process the data relevant to the operation of the two balloons.

Both counterpulsation techniques were tested in the pulse duplicator where the aortic pressure and flow data were collected. The software system then processes the data to calculate all of the parameters affected by counterpulsation.

While …

Reconstruction And Enhancement Of Medical Computed Tomography Images, Manoj K. Pattahil

Theses

The aim of Computed Tomography is to obtain information regarding the nature of the materials occupying precise positions inside the body. But due to errors in the projection data, which arise due to errors in measurement, beam hardening, missing data and noise, the reconstructed image has artifacts which reduces its diagnostic value. Thus the image obtained has to be processed to remove these artifacts and to improve the quality of the image. This is achieved by iterative reconstruction along with different post-reconstruction processing. Iterative reconstruction is done by repeating the process of projecting the image and creating new projection data …

Biomechanical Comparison Of Interosseous And Subperiosteal Flexor Tendon Reattachment, Alisa Beth Olin

Theses

This study was undertaken to biomechanically compare the interosseous and subperiosteal distal flexor tendon reattachment techniques. Twenty New Zealand white rabbits underwent division of the right second and third hind limb profundus flexor tendon distal to the insertion of the superficial flexor. All tendons were repaired using the Kleinnert-Bunnell configuration with a 5-0 nylon tied over a cotton pad on the dorsum of the digit. In half of the animals, the second profundus was reattached into a hole in the middle phalanx and the third profundus was reattached after periosteal stripping of the middle phalanx. The other animals underwent subperiosteal …