Digital Commons Network^™

A Detailed Approach For Concept Generation And Evaluation In A Technology Push Product Development Environment, Andrew Nelson

Theses and Dissertations

Many companies rely on successful product development as a means to increase their revenues and expand their operations. Market pull, the most common form of product development, begins with a specific customer, and focuses on how to satisfy that customer's needs. Technology push is a product development process where a technology is first discovered, then embodied in products that may be marketed to specific customers. Technology push presents several obstacles not encountered in market pull processes, such as a lack of a defined market, lack of established processes and difficulty in execution. These complications keep technology push from being more …

Dynamic Determinants Of Incisal Display, Shawn Paul Pesh

Loma Linda University Electronic Theses, Dissertations & Projects

The principal objective of this study was to use computer aided design (CAD) to better illustrate and quantify the relationship of mandibular arch depth, mandibular arch width, overbite, and overjet in the presence of mandibular dental crowding. To date, there has been no research examining how changes in the mandibular arch limit the orthodontist's ability to control overbite and overjet. Understanding how to effectively manage overbite and overjet are crucial to the clinician's ability to manipulate incisal display. Polyvinyl siloxane impressions of both maxillary and mandibular arches of a Caucasian patient were taken and used to pour dental stone models. …

Ricketts And Steiner Analysis Using Newtom 3g™ Scout Images, James I. Gibson Iii

Loma Linda University Electronic Theses, Dissertations & Projects

NewTom 3G™ scout images have the general appearance of traditional lateral cephalometric radiographs. The purpose of this research was to determine if Ricketts and Steiner analyses could be accomplished on NewTom 3G™ scout images.

This was a retrospective study comparing the use of NewTom 3G™ scans in DICOM (Digital Imaging and Communications in Medicine) format to scout images from 25 consecutive patients of the Loma Linda University School of Dentistry Department of Orthodontics, three of these patients did not meet the inclusion criteria. The DICOM images were used to create controls. The controls and scout images were digitized using QuickCeph™. …

Intravenous Polyethylene Glycol Inhibits The Loss Of Cerebral Cells After Brain Injury, Andrew O. Koob, Bradley S. Duerstock, Charles F. Babbs, Yinlong Sun, Richard B. Borgens

Weldon School of Biomedical Engineering Faculty Publications

We have tested the effectiveness of polyethylene glycol (PEG) to restore the integrity of neuronal membranes after mechanical damage secondary to severe traumatic brain injury (TBI) produced by a standardized head injury model in rats. We provide additional detail on the standardization of this model, particularly the use and storage of foam bedding that serves to both support the animal during the impact procedure and to dampen the acceleration of the brass weight. Further, we employed a dye exclusion technique using ethidium bromide (EB; quantitative evaluation) and horseradish peroxidase (HRP; qualitative evaluation). Both have been successfully used previously to evaluate …

Integration Of Micro Nano And Bio Technologies With Layer -By -Layer Self -Assembly, Dinesh Shankar Kommireddy

Doctoral Dissertations

In the past decade, layer-by-layer (LbL) nanoassembly has been used as a tool for immobilization and surface modification of materials with applications in biology and physical sciences. Often, in such applications, LbL assembly is integrated with various techniques to form functional surface coatings and immobilized matrices. In this work, integration of LbL with microfabrication and microfluidics, and tissue engineering are explored. In an effort to integrate microfabrication with LbL nanoassembly, microchannels were fabricated using soft-lithography and the surface of these channels was used for the immobilization of materials using LbL and laminar flow patterning. Synthesis of poly(dimethyldiallyl ammonium chloride)/poly(styrene sulfonate) …

Laser And Led Effects On The Proliferation Rate Of Periodontal Ligament Fibroblasts, Allen J. Job

Loma Linda University Electronic Theses, Dissertations & Projects

PURPOSE: To compare the effectiveness of a Gallium Aluminum Arsenide (GaAlAs) diode laser and a light emitting diode (LED) on periodontal ligament fibroblast cell proliferative rates.

METHODS and MATERIALS: PDLF obtained from freshly extracted permanent teeth were cultured under standard conditions until a subconfluent monolayer was present. The next section took 5 days to complete. On day 1, the initial cell concentration of 700 uL/cm² was plated on 96-well assay plates and placed in a CO₂ incubator at 37° C for 24 hours. On day 2, cell counts were first verified using hemocytometry then were irradiated using an …

The Processing, Mechanical Properties And Bioactivity Of Zinc Based Glass Ionomer Cements, D. Boyd, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The suitability of Glass Ionomer Cements (GICs) for use in orthopaedics is retarded by the presence in the glass phase of aluminium, a neurotoxin. Unfortunately, the aluminium ion plays an integral role in the setting process of a GIC and its absence is likely to hinder cement formation. However, zinc oxide, a bacteriocide, can act both as a network modifying oxide and an intermediate oxide in a similar fashion to alumina and so ternary systems based on zinc silicates often have extensive regions of glass formation. The purpose of this research was to produce novel GICs based on calcium zinc …

Combined Effects Of Prozac And Hypothalmic Mediated Response On Masseter Muscle Activity In The Cat, Chika P. Nwaorgu

Theses

The present study tested the hypothesis that infusion of Prozac would serve to suppress defensive rage elicited from the medial hypothalamus of the cat. Cats are known to exhibit certain kind of behavior, known as the "defensive rage response" such as unsheathing of the claws, retraction of the ear and vocalization (hissing).

Three adult cats (2 males and 1 female) weighing (2.8 - 3.4 kg) were utilized during the experiments. Cannula-electrodes were implanted into the medial hypothalamus for elicitation of defensive rage behavior. EMG activity was recorded with a bipolar electrode attached to the masseter muscle to establish baseline before …

Acoustics Of The Human Middle-Ear Air Space, Cara E. Stepp, Susan E. Voss

Engineering: Faculty Publications

The impedance of the middle-ear air space was measured on three human cadaver ears with complete mastoid air-cell systems. Below 500 Hz, the impedance is approximately compliance-like, and at higher frequencies (500-6000 Hz) the impedance magnitude has several (five to nine) extrema. Mechanisms for these extrema are identified and described through circuit models of the middle-ear air space. The measurements demonstrate that the middle-ear air space impedance can affect the middle-ear impedance at the tympanic membrane by as much as 10 dB at frequencies greater than 1000 Hz. Thus, variations in the middle-ear air space impedance that result from variations …

Biofilm Removal Using Bubbles And Sound, Michael R. Parini

Theses and Dissertations

Bacteria in biofilms adhere well to surfaces and are quite difficult to remove. Oral plaque is one example of a biofilm. Many researchers have studied ways to remove plaque and bacteria from surfaces. It has been found that the passage of a bubble across a surface to which bacteria has adhered can remove the bacteria from the surface. Biofilms of Streptococcus mutans were grown on glass coverslips as a simple model for oral plaque. The coverslips were mounted in a Plexiglas chamber filled with artificial saliva. A bubble stream was directed at the mounted biofilm. The velocity, gas fraction, median …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 8, June 2004, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Dynamic Matrix Composition In Engineered Cartilage With Stochastic Supplementation Of Growth Factors, Asit K. Saha, J. (Jagannath) Mazumdar, Sean S. Kohles

Mechanical and Materials Engineering Faculty Publications and Presentations

Dynamic extracellular matrix (ECM) synthesis is explored in a hypothesized engineered cartilage construct. Growth (α) and decay (β) rate parameters are developed from a previous engineered cartilage model. The presented mathematical model was constructed from the parameterized experimental data using a deterministic and stochastic examination of ECM synthesis based on a negative feedback control mechanism. A growth factor supplementation is incorporated in a probabilistic mathematical approach. The growth factor component modified an initial deterministic model through a Gaussian white noise fluctuation. As the primary constituents of ECM, the mathematical tool is intended to characterize the probable steady state distribution of …

Inside Unlv, Erin O'Donnell, Diane Russell, Carol C. Harter

Inside UNLV

No abstract provided.

Polyampholyte Hydrogel Characteristics And Detecting The Bacterial Interactions With These Hydrogels Using Digital Image Processing Methods, Ram Pratap Gangadharan

Masters Theses

In recent years, the unique physical properties of synthetic hydrogels have been exploited in a number of interesting and novel applications. In particular polyampholytes have been the subject of many theoretical studies since they provide a model for studying the longrange interactions found in proteins and other forms of soft condensed matter. In balanced polyampholytes the net electrostatic forces are attractive so that in low ionic salt concentration, the chains have a tendency to collapse into compact globules. Addition of salt, which screens these interactions, induces a swelling of the chain. However the electrostatic interactions between polymeric and mobile charges …

Evaluation Of The Effects On Human Performance Characteristics And Peak Head Accelerations With The Use Of Various Intra-Oral Appliances, Katie Lin Padgett

Masters Theses

Various studies have investigated the relationship between the mandibular position and its affect on human performance characteristics. To maintain the jaw in an optimal position Mandibular Orthopedic Repositioning Appliances (MORA) have been produced. A protective mouthguard is an appliance worn in the mouth which helps prevent injuries to the teeth, lips, cheek, tongue, and jaw as a result of impact. More recently, it has been hypothesized that mouthguards reduce the risk of concussion by attenuating the impact to the jaw rather than transferring the force to the brain. Currently, there are no standards for testing protective mouthguards. Such a test …

Design And Development Of A Mems-Based Capacitive Bending Strain Sensor And A Biocompatible Housing For A Telemetric Strain Monitoring System., Julia Marie Weyer Aebersold 1969-

Electronic Theses and Dissertations

Lumbar arthrodesis or spinal fusion is usually performed to relieve back pain and regain functionality from ruptured discs, disc degenerative disease, trauma and scoliosis. Metal rods are often fixed to the spine with screws or hooks, while fusion develops on the affected vertebrae. Fusion is determined by visual examination of radiographic images (X-ray), computed tomography (CT) scans or magnetic resonance imaging (MRI), yet these inspection procedures are subjective methods of review. They do not objectively confirm the presence of spinal fusion, which can lead to exploratory surgery to determine if fusion has occurred. Therefore, a need has arisen to develop …

The Purposes And Evaluation Methods For State Residential General Contractor Licensing, James Ellis Fenn

Theses and Dissertations

The main topic in the licensing debate is whether licensing affects construction quality. Available literature and previous studies indicate that it does not. The real question is not whether licensing improves quality, but whether the improving quality is the actual purpose of licensing. There is little information available on the purpose of licensing as defined by state licensing departments as well as a general lack of information on how states evaluate whether licensing is fulfilling the intended purpose. In order to effectively resolve some of the issues surrounding the construction licensing debate, the true purpose of licensing and the methods …

An Analysis Into The Effectiveness Of Aircraft Maintenance Under The Combat Wing Structure, Derrick R. Barthol

Theses and Dissertations

Organizational structure builds the foundation from which organizations operate. To gain full potential of structural efficiencies in the current operating environment, public and private firms are continually modifying their organizational structure. The U.S. Air Force is no different and underwent its most recent reorganization in the fall of 2002 replacing the post-Gulf War format of the previous decade. Air Force leadership needs to understand how well the current structure is performing at achieving its intended objectives. This research investigates the effectiveness of the recent change to Air Force organizational structure on aircraft maintenance performance through an analysis of aircraft maintenance …

Boundary Layer Flow Control Using Plasma Induced Velocity, Brian E. Balcer

Theses and Dissertations

An examination of the effects of plasma induced velocity on boundary layer flow was conducted. A pair of thin copper film electrodes spanned the test section, oriented at thirty degrees from normal to the free stream flow. An adverse pressure gradient was imposed over the electrode configuration using a pressure coefficient profile similar to that associated with suction side of a Pac-B low pressure turbine blade. In addition, suction was applied to keep flow attached on the upper wall, inducing separation over the electrode. The electrode is supplied by an AC source at three different power levels with the free …

Medical Devices, Support Networks, And Their Vulnerabilities: A Case Study Of The Integration Of Medical Networks Into The Air Force Information Network, Paul G. Oleksiak

Theses and Dissertations

With the implementation of "one Air Force, one network" under way it is important to look at how the Air Force plans to incorporate the medical field and its unique systems, networks, and mission. The medical field presents distinctive problems not seen in other areas. Open network vulnerabilities in the medical information systems not only pose a problem for the individual, but to the military service also. Possible security holes provide both access to vital military & personal information (end strength numbers, current status of personnel, social security), and a door way into the "network". Intruders now can possibly access …

An In Vitro Comparison Of The Rake Angles Between K3 And Profile Endodontic File Systems, David Y. Chow, Sheila E. Stover, James Bahcall, Andris Jaunberzins, Jeffrey M. Toth

Biomedical Engineering Faculty Research and Publications

The purpose of this study was to compare rake angles of the ProFile and K3 file systems. Twenty-five 40/0.06 taper files were obtained for each system. Five files from the same manufacturer were placed perpendicularly into a vial of Epoxicure Resin and left to set for 24 h. The set-ups were removed from the vials and each were sectioned 5 mm from the tip of the files and polished. A photomicrograph was taken of each file with 100× magnification. Five sets of ProFile and five sets of K3 files were processed in this manner. Images were captured digitally, and rake …

Working Postures Of Dentists And Dental Hygienists, Richard W. Marklin, Kevin Cherney

Mechanical Engineering Faculty Research and Publications

A joint study was conducted by a manufacturer of dental stools in the Midwest of the United

States and Marquette University to measure the occupational postures of dentists and dental hygienists. The postures of 10 dentists and 10 dental hygienists were assessed using work sampling and video techniques. Postura! data of the neck, shoulders and lower back were recorded from video and categorized into 30-degree intervals: O (neutral posture of respective joint), 30, 60 and 90 degrees. Each subject's postures were observed while they were treating patients during a four-hour period, during which 100 observations of postures were recorded at …

Instrumented Nanoindentation Studies Of Deformation In Shape Memory Alloys, Sudhir Rajagopalan

Electronic Theses and Dissertations

Near equi-atomic nickel titanium (NiTi) shape memory alloys (SMAs) are a class of materials characterized by their unique deformation behavior. In these alloys, deformation mechanisms such as mechanical twinning and stress induced phase transformation between a high symmetry phase (austenite) and a low symmetry phase (martensite) additionally occur and influence mechanical behavior and thus their functionality. Consequently, applications of SMAs usually call for precise phase transformation temperatures, which depend on the thermomechanical history and the composition of the alloy. Instrumented indentation, inherently a mechanical characterization technique for small sampling volumes, offers a cost effective means of empirically testing SMAs in …

A Novel Role For Gadd45Β As A Mediator Of Mmp-13 Gene Expression During Chondrocyte Terminal Differentiation, Kosei Ijiri, Luiz F. Zerbini, Haibing Peng, Ricardo G. Correa, Binfeng Lu, Nicole Walsh, Yani Zhao, Noboru Taniguchi, Xu-Ling Huang, Hasan H. Otu, Hong Wang, Jian Fei Wang, Setsuro Komiya, Patricia Ducy, Mahboob U. Rahman, Richard A. Flavell, Ellen M. Gravallese, Peter Oettgen, Towia A. Libermann, Mary B. Goldring

Department of Electrical and Computer Engineering: Faculty Publications

The growth arrest and DNA damage-inducible 45β (GADD45β) gene product has been implicated in the stress response, cell cycle arrest, and apoptosis. Here we demonstrated the unexpected expression of GADD45β in the embryonic growth plate and uncovered its novel role as an essential mediator of matrix metalloproteinase-13 (MMP-13) expression during terminal chondrocyte differentiation. We identified GADD45β as a prominent early response gene induced by bone morphogenetic protein-2 (BMP-2) through a Smad1/Runx2-dependent pathway. Because this pathway is involved in skeletal development, we examined mouse embryonic growth plates, and we observed expression of Gadd45β mRNA coincident with Runx2 protein …

Haptic-Based Dental Procedure Training Simulator, Cristian Luciano

Link Foundation Modeling, Simulation and Training Fellowship Reports

Since the beginning of the last century, simulators have been widely used in military and aviation. Recently, the use of simulation in medicine and dentistry has brought the attention of the research community, looking for efficient ways to increase patient's safety by improving surgeon's and dentist's skills. Traditionally, plastic mannequins and cadavers were used to train medical and dental students. However, the lack of details and differences on material properties (in the case of mannequins), and high costs and ethical issues (in the case of cadavers)- supported by the lately improvements of virtual reality, haptics and robotics - have increased …

Defluroridation Using A Continuous Electrocoagulation (Ec) Reactor, Mohammad Emamjomeh, Muttucumaru Sivakumar

Faculty of Engineering - Papers (Archive)

Electrocoagulation (EC) is a process of passing a steady electric current through liquid using aluminium or iron electrodes to remove impurities in water. When aluminium electrodes are used, the aluminium goes into solution at the anode and hydrogen gas is released at the cathode and dissolution of A1 anodes produces aqueous aluminium species. Experiments were undertaken to investigate the effects of the different parameters such as: current density (12.5-50 A/m2), flow rate (150-400 mL/min), initial pH (4-8), and initial fluoride concentration (5-15 mg/L) on the fluoride removal efficiency in a continuous flow electrocoagulator. The experimental results showed that for an …

Dilation Of The Oropharynx Via Selective Stimulation Of The Hypoglossal Nerve, Jingtao Huang

Doctoral Dissertations

Obstructive sleep apnea (OSA) is caused by the retraction of the tongue to occlude the upper airway (UAW). Electrical stimulation of the tongue protrudor and retractor muscle has been demonstrated as an effective technique to alleviate UAW obstructions and is considered to be a potential treatment for OSA. Recent studies have shown that selective stimulation of the hypoglossal nerve (HG) to activate tongue muscles using a single implantable device presents an attractive approach for treating OSA. In this study, the functional outcome of selective hypoglossal nerve stimulation with a multi-contact peripheral nerve electrode was studied by imaging the airway in …

Attainable Compressive Strength Of Pervious Concrete Paving Systems, Ann Marie Mulligan

Electronic Theses and Dissertations

The pervious concrete system and its corresponding strength are as important as its permeability characteristics. The strength of the system not only relies on the compressive strength of the pervious concrete but also on the strength of the soil beneath it for support. Previous studies indicate that pervious concrete has lower compressive strength capabilities than conventional concrete and will only support light traffic loadings. This thesis investigated prior studies on the compressive strength on pervious concrete as it relates to water-cement ratio, aggregate-cement ratio, aggregate size, and compaction and compare those results with results obtained in laboratory experiments conducted on …

Electrochemical Method For Fluoride Removal: Measurement, Speciation And Mechanisms, Muttucumaru Sivakumar, Mohammad Mahdi Emamjomeh

Faculty of Engineering - Papers (Archive)

Electrocoagulation/flotation (ECF) is a process of passing a steady electric current through a liquid to remove a known contaminant. When aluminium electrodes are used, the aluminium goes into solution at the anode and produces aqueous aluminium species and hydrogen gas is released at the cathode. The experimental results indicate that the pH of solution is an important factor in the removal of fluoride. The optimal pH was found to be between 6 and 7.5. When pHA l {O H )+2are predominant and aluminium hydroxide is tended soluble. However when pH>9, soluble species Al(OH)4 is found to be predominant species. …

Design Of A Dynamic Focusing Microscope Objective For Oct Imaging, Supraja Murali

Electronic Theses and Dissertations

Optical Coherence Tomography (OCT) is a novel optical imaging technique that has assumed significant importance in bio-medical imaging in the last two decades because it is non-invasive and provides accurate, high resolution images of three dimensional cross-sections of body tissue, exceeding the capabilities of the current predominant imaging technique –ultrasound. In this thesis, high resolution OCT is investigated for in vivo detection of abnormal skin pathology for the early diagnosis of cancer. The technology presented is based on a dynamic focusing microscopic imaging probe conceived for skin imaging and the detection of abnormalities in the epithelium. A novel method for …