Biomedical Devices and Instrumentation Commons^™

Control System For Mass Spectrometer, Jian Xu

Purdue Polytechnic Masters Theses

Mass spectrometry (MS) is a very popular analytical methodology that measures the mass of ions using a mass spectrometer. It is widely used for determining masses of chemicals, the elemental composition of a sample and molecule structure. The process of mass spectrometry normally consists of ionizing chemical compounds to ions and measuring their ratios of mass to charge for analysis.

MS instruments consist of three modules: Ionization, Analysis and detection. A LabVIEW system was developed to control the three modules of a mass spectrometer, giving the required signals in a right sequence. Experiments can be carried out by using the …

Design Of A Pragmatic Test Lab For Evaluating And Testing Wireless Medical Devices For Deployment On An Integrated It Wireless Network, Allie Paquette

Master's Theses

In today’s healthcare environment, networking of medical devices is becoming more and more prevalent. There is an increasing need for mobile technology to meet clinical needs. Wireless communication is essential for allowing medical devices to be able to move with the patient, while continuing to record and communicate patient data. A traditional example is telemetry monitoring, but other examples of wireless utilization include sending ECG test results to the EMR or remotely updating the drug library on numerous IV pumps. Each wireless application has varying demands on the connectivity infrastructure and will share radio frequency (RF) spectrum resources with a …

Noninvasive Assessment Of Joint Motion Over Long Durations: System Evaluation And Data Analysis Methods, Maria J. Qadri

Master's Theses

The development, progression, and treatment of degenerative musculoskeletal diseases, such as carpal tunnel and shoulder impingement syndromes, may be better characterized when joint motions are assessed over long durations outside clinical, laboratory, or rehabilitation settings that involve standardized assessment, exercise protocols, and/or regimented movements. Assessment methods for human movement capture beyond laboratory or clinical experiments are typically limited to short capture times of less than one hour. Noninvasive, long-duration measurements of joint motion in occupational settings provides more insight into movement patterns and quantitative assessments regarding joint usage, which lead to a better understanding of the cumulative effects associated with …

A Comparative Study Of Total Hemoglobin Measurement Technology: Noninvasive Pulse Co-Oximetry And Conventional Methods, Jared S. Ruckman

Master's Theses

Hemoglobin can be measured on a variety of devices using different principles of operation. Noninvasive pulse CO-oximetry represents the latest development in hemoglobin measuring technology. The technology uses principles similar to pulse oximetry to measure total hemoglobin, oxyhemoglobin, reduced oxyhemoglobin, carboxyhemoglobin and methemoglobin. Similar to the introduction of pulse oximetry to the medical field, pulse CO-oximetry has been met with skepticism. Since the technology is noninvasive and provides continuous monitoring in comparison to invasive and discrete techniques used in other methods, CO-oximetry purportedly provides an advantage in patient care. The purpose of this research is threefold: (a) to review the …

Construction And Use Of A Direct Calorimeter To Estimate Energy Expenditure In Hibernators, Mark S. Burger, Frank Van Breukelen

Festival of Communities: UG Symposium (Posters)

Metabolic rates have traditionally been estimated through indirect calorimetry (gas exchange or respirometry) due to its ease and availability. Oxygen consumption neglects the contributions of anaerobic metabolism, while direct calorimetry (heat production) estimates both anaerobic and aerobic metabolism. Walsberg and Hoffman (2005) report anaerobic metabolism may be more important to small rodents than was previously thought. During the non-steady state of mammalian hibernation, we hypothesize that anaerobic processes may play an even greater role in fueling metabolism. To address this question, we constructed a very sensitive calorimeter that utilizes the Seebeck effect from a thermoelectric element (Peltier device). We describe …

Gas Embolic Factors In Cardiovascular Health, Eric L. Cutler

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Gas emboli are a clinical issue often encountered in the space exploration, marine construction, and medical fields.  Individuals involved with these disciplines will often have asympomatic gas emboli circulating throughout their bodies on a regular basis.  A study into the impact of chronic asymptomatic gas emboli on the risk of atherosclerosis in humans is thus presented.  This research utilized a custom built cardiovascular flow simulator and accompanying data acquisition system to experimentally determine the influence of gas emboli under varied circumstances on the mean wall shear stress of a tube in-vitro.  A directly inverse relationship between gas embolus presence in …

Leaching Of Potential Hazardous Elements Of Coal Cleaning Rejects, Luis F.O. Silva, Maria Izquierdo, Xavier Querol, Robert B. Finkelman, Marcos L.S. Oliveira, Marcus Wollenschlager, Mark R. Towler, Rafael Pérez-López, Felipe Macias

Chemical and Biochemical Engineering Faculty Research & Creative Works

The geochemical characteristics of coal cleaning rejects (CCR) in Santa Catarina State, Brazil, were investigated. Around 3.5 million ton/ year of coal waste are dumped in Santa Catarina State. Coal beneficiation by froth flotation results in large amounts of CCR composed of coaly and mineral matter, the latter characterized by the occurrence of sulphide minerals and a broad array of leachable elements. The total and leachable contents of more than 60 elements were analyzed. Atmospheric exposure promotes sulphide oxidation that releases substantial sulphate loads as well as Ca²⁺, K⁺, Mg²⁺, Cl- and Al^{3+ …}

Universal Engineering Programmer – An In-House Development Tool For Developing And Testing Implantable Medical Devices In St. Jude Medical, Khoa Tat Do

Master's Theses

During development and testing of the functionality of the pacemaker and defibrillator device, engineers in the St. Jude Medical Cardiac Rhythm Management Division use an in-house development tool called Universal Engineering Programmer (UEP) to ensure the device functions as expected, before it can be used to test on an animal or a human during the implantation process.  In addition, some applications of UEP are incorporated into the official releases of the device product.  UEP has been developed and used by engineers across departments in the St. Jude Medical Cardiac Rhythm Management Division (CRMD).  This thesis covers the flexible and reusable …

The Structural Role Of Titanium In Ca-Sr-Zn-Si/Ti Glasses For Medical Applications, A. W. Wren, F. R. Laffir, A. Kidari, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glasses for medical applications are used in particulate form or as a cement component. This work was undertaken to determine structural changes in 0.48SiO₂-0.36ZnO-0.12CaO-0.04SrO glass when the SiO₂ is substituted with 5 mol% increments of TiO2. X-ray Diffraction (XRD) was used to determine the presence of crystallinity. This occurred after additions of 20 mol% TiO₂. Differential Thermal Analysis (DTA) and Network connectivity (NC) calculations determined that by increasing the TiO₂ content, the T_g and NC reduced (T_g 670 °C to 632 °C, NC 1.83 to -1.14) suggesting that TiO₂ acts as …

Laser Etched Pmma Microfluidic Chip Design And Manufacture With Applications In Capillary Zone Electrophoresis, Evan Allen Barbre

Master's Theses

This thesis encompasses a feasibility study of using low-cost materials to manufacture microfluidic chips that can perform the same functions as chips manufactured using traditional methods within an acceptable range of efficiency of chips created with more exotic methods and materials. The major parts of the project are the selection and characterization of the fabrication methods for creating the channels for fluid flow, the methods for sealing the channels to create a usable chip and the electrophoretic separations of carboxylated microspheres of different potentials. In this work we seek to answer the question if laser-etched PMMA microfluidic chips are comparable …

Sar Map Of Gel Phantom In A 64mhz Mri Birdcage By Fiber-Optic Thermometry And Fdtd Simulation, Chirag Mukesh Patel

Master's Theses

As implantable medical devices are being used more often to treat medical problems for which pharmaceuticals don’t suffice, it is important to understand their interactions with commonly used medical modalities. The interactions between medical implants and Magnetic Resonance Imaging machines have proven to be a risk for patients with implants.

Implanted medical devices with elongated metallic components can create harmful levels of local heating in a Magnetic Resonance Imaging (MRI) environment [1]. The heating of a biological medium under MRI is monitored via the Specific Absorption Rate (SAR). SAR, defined as power absorbed per unit mass (W/kg), can be calculated …

Novel Bioelectrical Measurement Using A Digital Biopotential Monode, Mark Nolan, Edward Burke, Eugene Coyle

Conference Papers

In conventional biopotential recording, two or more electrodes are placed on the body. A unipolar lead records the time-varying electrical potential at a single point (relative to a reference potential) via one signal electrode. A bipolar lead records the time-varying potential difference between two points via two signal electrodes. In each case, the signal electrodes are connected to high impedance amplifier inputs, while an additional electrode provides a low-impedance path between the amplifier and human subject. Bipolar leads are usually preferred since interference appearing at both signal electrodes can be eliminated using an instrumentation amplifier with high CMRR. A drawback …

Intelligibility Of Electrolarynx Speech Using A Novel Hands-Free Actuator, Brian Madden, Mark Nolan, Ted Burke, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal or plastic plate at a frequency within the range of glottal excitation. In this paper, the intelligibility of speech produced using a novel hands-free actuator is compared to speech produced using a conventional electrolarynx. Two able-bodied speakers (one male, one female) performed a closed response test containing 28 monosyllabic words, once using a conventional electrolarynx and a second time using the novel design. The resulting audio recordings …

Augmented Control Of A Hands-Free Electrolarynx, Brian Madden, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx acts as the sound source, providing a quasi-periodic excitation of the vocal tract. Following a total laryngectomy, some people speak using an electrolarynx which employs an electromechanical actuator to perform the excitatory function of the absent larynx. Drawbacks of conventional electrolarynx designs include the monotonic sound emitted, the need for a free-hand to operate the device, and the difficulty experienced by many laryngectomees in adapting to its use. One improvement to the electrolarynx, which clinicians and users frequently suggest, is the provision of a convenient hands-free control facility. This would allow more natural use of …

High Power, Low Frequency Ultrasound: Meniscal Tissue Interaction And Ablation Characteristics, Brendan O'Daly, Edmund Morris, Graham Gavin, Conor Keane, John O Byrne, Garrett Mcguinness

Articles

Abstract—This study evaluates high power low frequency ultrasound transmitted via a flat vibrating probe tip as an alternative technology for meniscal debridement in the bovine knee. An experimental force controlled testing rig was constructed using a 20 kHz ultrasonic probe suspended vertically from a load cell. Effect of variation in amplitude of distal tip displacement (242–494 mm peak-peak) settings and force (2.5–4.5 N) on tissue removal rate (TRR) and penetration rate (PR) for 52 bovine meniscus samples was analyzed. Temperature elevation in residual meniscus was measured by embedded thermocouples and histologic analysis. As amplitude or force increases, there is a …

Design, Fabrication, And Testing Of An Electrospinning Apparatus For The Deposition Of Pmma Polymer For Biomedical Applications, Harsha Malshe

Inquiry: The University of Arkansas Undergraduate Research Journal

This paper describes the successful design and fabrication of a deposition system for synthesis and assembly of nanoscale and submicron sized fibers of poly(methylmethacrylate)(PMMA) polymer. To optimize the electrospinning deposition process, the distance between the needle and the electrically grounded substrate, the applied voltage, and the concentration of PMMA polymer in the solution were varied. PMMA fibers as small as 500 nanometers were observed using scanning electron microscopy (SEM). The chemical signature of PMMA was confirmed for best quality and retention of chemistry using Fourier Transformed Infrared spectroscopy (FT-IR). PMMA is a biocompatible polymer, and nanofibers of PMMA are key …

In-Silico Hyperthermia Performance Of A Near-Field Patch Antenna At Various Positions On A Human Body Model, Sergio Curto, Terrence See, Patrick Mcevoy, Max Ammann, Zhi Ning Chen

Articles

A compact patch applicator designed to enhance targeted energy coupling at 434 MHz is a key enabler for sensitizing temperature increments in body regions containing superficial tumours. A detailed FDTD body model is used to explore simulated RF coupling and temperature increments for typical clinical conditions. The antenna impedance matching, specific absorption rate and thermal distribution parameters are evaluated to identify applied performance outcomes. The analysis reveals physiological-RF coupling patterns for an optimised closely-coupled single element applicator.

On Improving Electrooculogram-Based Computer Mouse Systems: The Accelerometer Trigger, Johnalan Keegan, Edward Burke, James Condron, Eugene Coyle

Conference Papers

Eye tracking is a well-established method of computer control for profoundly paralysed people (Anson et al., 2002). Cameras are commonly used to track eye movements (Morimoto et al., 2005) but one alternative is the bioelectrical signal known as the electrooculogram (EOG). There are some EOG mouse control systems that facilitate the use of GUI applications, but certain actions, which are straightforward using a conventional mouse, remain impossible. Unless the eyes are tracking a target, they move in saccades (jumps), making it impossible to voluntarily trace out smooth trajectories with one's gaze, as would be required to draw a smooth curve. …

The Bioactivity And Ion Release Of Titanium-Containing Glass Polyalkenoate Cements For Medical Applications, A. W. Wren, N. M. Cummins, F. R. Laffir, S. P. Hudson, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The ion release profiles and bioactivity of a series of Ti containing glass polyalkenoate cements. Characterization revealed each material to be amorphous with a T_g in the region of 650-660°C. The network connectivity decreased (1.83-1.35) with the addition of TiO₂ which was also evident with analysis by X-ray photoelectron spectroscopy. Ion release from cements were determined using atomic absorption spectroscopy for zinc (Zn^₂₊), calcium (Ca^₂₊), strontium (Sr^₂₊), Silica (Si^₄₊) and titanium (Ti4+). Ions such as Zn^₂₊ (0.1-2.0 mg/l), Ca²⁺ (2.0-8.3 mg/l,) Sr²⁺ (0.1-3.9 mg/l), and S^{i4+ …}

Arterial Tissue Perforation Using Ultrasonically Vibrating Wire Waveguides, Mark Wylie

Doctoral

Chronic Total Occlusions (CTOs) are fibrous and calcified atherosclerotic lesions which completely occlude the artery. They are difficult to treat with standard dilation procedures as they cannot be traversed easily. Their treatment is also associated with a high risk of arterial perforation. Low frequency ultrasonic vibrations delivered via wire waveguides represent a minimally invasive treatment for CTOs and other tissue ablation applications. These devices typically operate at 20–50 kHz delivering wire waveguide distal tip amplitudes of vibration of 0-60 μm. The diseased tissue is ablated or disrupted by repetitive direct mechanical contact and cavitation. This research assesses the susceptibility of …