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The Spaceflight Environment And The Skeletal System, Eric Bandstra Aug 2008

The Spaceflight Environment And The Skeletal System, Eric Bandstra

All Dissertations

The spaceflight environment presents many challenges to the human body. Bone loss in astronauts is a well known consequence of reduced loading in the weightless environment of low-earth orbit. Recent studies have also indicated that spaceflight relevant types of radiation (at relatively high doses) have deleterious effects on trabecular bone. Both of these represent potential skeletal challenges during long-duration spaceflight. The objective of these studies is to examine the response of bone to models of the spaceflight environment.
Astronauts will likely absorb doses of protons and heavy ions during lengthy missions outside the Earth's magnetosphere. Following exposure to a range …


Chitosan Derivatives For Tissue Engineering, Yongzhi Qiu Aug 2008

Chitosan Derivatives For Tissue Engineering, Yongzhi Qiu

All Dissertations

Chitosan, a naturally occurring polysaccharide, and its derivatives have been widely explored for biomedical applications due to their biocompatibility and biodegradability. In our studies, we developed a series of chitosan derivatives through chemical modifications. These chitosan derivatives not only possess better processibility in scaffolds fabrication, but also show excellent potentials in tissue engineering applications, including blood vessel and bone tissue engineering.
The excellent antithrombogenic property is crucial for vascular engineering applications, especially in engineering small-diameter blood vessels. In our studies, chitosan was chemically modified by phthalization and the phthalized chitosan exhibited great antithrombogenic property. Through a wet- phase-inversion process, tubular …


Design, Construction, And Performance Of Low-Level Radioactive Waste Disposal Facility, Rudolph Bonaparte, John F. Beech, Leslie M. Griffin, David K. Phillips, Uday Kumthekar, Johnny Reising Aug 2008

Design, Construction, And Performance Of Low-Level Radioactive Waste Disposal Facility, Rudolph Bonaparte, John F. Beech, Leslie M. Griffin, David K. Phillips, Uday Kumthekar, Johnny Reising

International Conference on Case Histories in Geotechnical Engineering

A mixed low-level radioactive waste (LLRW) and Resource Conservation and Recovery Act (RCRA) waste on-site disposal facility (OSDF) was constructed as part of the remediation of the U.S. Department of Energy Feed Material Production Center in Fernald, Ohio. The 56-acre OSDF is fully constructed, filled with waste, and closed. Post-closure monitoring is ongoing. This paper presents the design, construction, and performance of the OSDF. Waste acceptance criteria and waste placement requirements are described. Results from three sets of pre-design field and laboratory investigations are summarized. Currently available performance data for the OSDF’s leachate collection system and leakage detection system are …


An Investigation On Failure Of Embankments In Bangladesh, Zakaria Hossain, Zahurul Islam, Toshinori Sakai Aug 2008

An Investigation On Failure Of Embankments In Bangladesh, Zakaria Hossain, Zahurul Islam, Toshinori Sakai

International Conference on Case Histories in Geotechnical Engineering

The study presents the results of case histories on failure of embankments in Bangladesh based on the field visits to the embankments sites, collected data and information on failure of embankments necessary data related to embankments construction practice obtained from available publications and soil conditions of the breached embankments in Bangladesh. Efforts have been made to discuss briefly the causes of embankment failure and its possible remedial measures. Two recent failures of embankments that occurred in the year 2007 are taken into consideration for a detailed study. For each case, embankment failure mechanism, construction method used for the embankments, soil …


General Report — Session 3: Case Histories And Failures In Geotechnical Earthquake Engineering, Robert Kayen, Sp Gopal Madabhushi, James R. Martin Ii Aug 2008

General Report — Session 3: Case Histories And Failures In Geotechnical Earthquake Engineering, Robert Kayen, Sp Gopal Madabhushi, James R. Martin Ii

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.


Destructive Water-Borne Pressure Waves, Gregory L. Hempen Aug 2008

Destructive Water-Borne Pressure Waves, Gregory L. Hempen

International Conference on Case Histories in Geotechnical Engineering

Many energetic sources (blasting, pile-driving, seismic exploration, …) near or within a water body may produce destructive, water-borne pressure waves. Pressure waves of sufficient amplitude can impact water-side structures and aquatic fauna. Such energetic sources produce pressure waves and cavitation that can cause concrete to spall, deform metal sheets that are near to the source, kill aquatic organisms, and/or damage hearing of marine mammals at large distances. Any program (energetic systems) that causes pressure waves within the water layer may be conducted in a manner that reduces the pressure waves’ severity. The methodology to reduce pressure waves does not need …


Characterization Of The Shear-Induced Potential (Sip) In Clay And The Application To Landslide Sites, Koichi Nakagawa, Shigenobu Yamada, Isamu Tsuka Aug 2008

Characterization Of The Shear-Induced Potential (Sip) In Clay And The Application To Landslide Sites, Koichi Nakagawa, Shigenobu Yamada, Isamu Tsuka

International Conference on Case Histories in Geotechnical Engineering

Electrical polarizations were observed in common fine soil aggregates in shear deformation tests and simulations conducted in a laboratory. This electric potential is called Shear-induced Potential (SIP). The SIP can be interpreted as the physicochemical interaction between the surface of clay particles and interstitial water by the kinetics of the electric double layer. The SIP could not be detected in a remolded craft clay sample, which was possibly treated with electrically non-dipole oil. In the laboratory, a plane strain test under the un-drained condition was carried out to reveal the characteristics of the polarization accompanying the shear deformation. Gouges from …


Foundations For Memorials And Monuments On The National Mall, Douglas W. Christie Aug 2008

Foundations For Memorials And Monuments On The National Mall, Douglas W. Christie

International Conference on Case Histories in Geotechnical Engineering

As the western end of the National Mall in Washington, DC was made by filling in portions of the Potomac River, memorials and monuments have required deep foundations. The site history including stream channels, canals, and materials used in filling various areas has had a large impact on the development of the Mall. Variations in geologic conditions along the Mall have affected the types of foundations used. One of the earliest structures, the Washington Monument, was sited to account for problem soils. Its foundation was underpinned during construction to compensate for low-strength soils. Shallow-founded portions of the Lincoln Memorial, the …


Qinghai-Tibet Railway, China And The Solutions To Its Major Geotechnical Problems For Construction, Lanmin Wang, Zhijian Wu, Junjie Sun, Luxin Zhang Aug 2008

Qinghai-Tibet Railway, China And The Solutions To Its Major Geotechnical Problems For Construction, Lanmin Wang, Zhijian Wu, Junjie Sun, Luxin Zhang

International Conference on Case Histories in Geotechnical Engineering

The Qinghai-Tibet Railway (QTR) is the highest-elevation one for passenger trains in the world and the first railway to connect central China to Tibet. Construction of this railway starting in 2001 had to contend with major geotechnical challenges, such as permafrost, environmental protection and seismic hazards. Its completion in 2006 is a remarkable feat in the world’s railway construction history and crystallization of wisdom of human beings. In this paper, the planning and preparing history and the construction project of QTR are introduced. The major three thorny problems, permafrost, lack of oxygen and environmental frangibility for the construction and their …


A Historical Perspective On Geotechnical Case Histories Courses, J. David Rogers Aug 2008

A Historical Perspective On Geotechnical Case Histories Courses, J. David Rogers

International Conference on Case Histories in Geotechnical Engineering

Ralph Peck introduced the concept of using a geotechnical case histories course to teach students problem solving and technical communications skills, beginning around 1956. This course was developed as a professional practice course at the graduate level, intended for civil engineers of diverse backgrounds as well as geoscientists. Students were required to prepare one-page summaries of each case history profiled in the course, a requirement that left an enormous impression on the students. A different approach was employed by the University of California, Berkeley, beginning around 1970. Berkeley offered two graduate courses in the mold of ABET “capstone courses,” graduate …


Google Earth Mapping Of Damage From The Niigata-Ken-Chuetsu M6.6 Earthquake Of 16 July 2007, Robert Kayen, Wm. Clint Steele, Brian Collins, Kevin Walker Aug 2008

Google Earth Mapping Of Damage From The Niigata-Ken-Chuetsu M6.6 Earthquake Of 16 July 2007, Robert Kayen, Wm. Clint Steele, Brian Collins, Kevin Walker

International Conference on Case Histories in Geotechnical Engineering

We describe the use of Google Earth during and after a large damaging earthquake that struck the central Japan coast on 16 July 2007 to collect and organize damage information and guide the reconnaissance activities. This software enabled greater real-time collaboration among scientists and engineers. After the field investigation, the Google Earth map is used as a final reporting product that was directly linked to the more traditional research report document. Finally, we analyze the use of the software within the context of a post-disaster reconnaissance investigation, and link it to student use of Google Earth in field situations.


Using New Signal Processing Techniques In Analyzing Masjed Soleyman Embankment Dam's Explosion Records, M. Davoodi, M. K. Jafari, M. Amel Sakhi Aug 2008

Using New Signal Processing Techniques In Analyzing Masjed Soleyman Embankment Dam's Explosion Records, M. Davoodi, M. K. Jafari, M. Amel Sakhi

International Conference on Case Histories in Geotechnical Engineering

Blasting test studies have one drawback with regard to earthquake studies; they are concerned with vibrations of much smaller amplitude than those normally encountered in earthquakes. Consequently, blasting studies can be used to calibrate dam behavior in a linear elastic range. Accuracy of numerical models should be improved by full scale tests and in situ earthquake records. In this research, first of all a short review of different classical and modern signal processing methods is presented. As it is known, classical signal processing methods, such as FFT and PSD, have many limitations in non- stationary random vibration analysis. Blasting records …


A New International Database On Case Histories Of Monitored Construction Of Tunnels And Deep Excavations, Fabrice Emeriault, Richard Kastner, Rodolphe Louis-Sidney, Elöd Egyed-Zsigmond Aug 2008

A New International Database On Case Histories Of Monitored Construction Of Tunnels And Deep Excavations, Fabrice Emeriault, Richard Kastner, Rodolphe Louis-Sidney, Elöd Egyed-Zsigmond

International Conference on Case Histories in Geotechnical Engineering

The prototype of a new database for case histories of monitored construction of tunnels and deep excavations is presented in this paper. The basic requirements for this database have been established by the members of the Technical Committee TC28 of the International Society for Soil Mechanics and Geotechnical Engineering. It is based on the Content Management System (CMS) Typo3. The resulting structure is flexible, the data being mirrored on sites managed by each participant providing data. It uses a web interface where the user can navigate and access to the data via an indexed search engine. Some very basic and …


Image-Guided Raman Spectroscopic Recovery Of Canine Cortical Bone Contrast In Situ, Subhadra Srinivasan, Matthew Schulmerich, Jacqueline H. Cole, Kathryn Dooley, Jaclynn M. Kreider, Brian W. Pogue Aug 2008

Image-Guided Raman Spectroscopic Recovery Of Canine Cortical Bone Contrast In Situ, Subhadra Srinivasan, Matthew Schulmerich, Jacqueline H. Cole, Kathryn Dooley, Jaclynn M. Kreider, Brian W. Pogue

Dartmouth Scholarship

Raman scattering provides valuable biochemical and molecular markers for studying bone tissue composition with use in predicting fracture risk in osteoporosis. Raman tomography can image through a few centimeters of tissue but is limited by low spatial resolution. X-ray computed tomography (CT) imaging can provide high-resolution image-guidance of the Raman spectroscopic characterization, which enhances the quantitative recovery of the Raman signals, and this technique provides additional information to standard imaging methods. This hypothesis was tested in data measured from Teflon tissue phantoms and from a canine limb. Image-guided Raman spectroscopy (IG-RS) of the canine limb using CT images of the …


Department Of Biological Systems Engineering Newsletter, Volume 4, Number 1, August 2008 Aug 2008

Department Of Biological Systems Engineering Newsletter, Volume 4, Number 1, August 2008

BSE Department Magazine

Contents:
New Biomedical Lab Makes Debut
From the Department Head
The Dean's List
Meet the Faculty
Alumni News
Student News
UCARE
Graduates
John Miller: A Success Story
Discover Your Career: Mechanized Systems Management
Alumnus Profile
Faculty and Staff News
Comings and Goings
Spreading the word about No-till


Exploratory Study Of Gold Nanoshell As A Therapeutic Thermal Ablation Agent For Cancer Treatment Using Laboratory And Animal Tissue Phantoms, Yajuvendra Rathore Aug 2008

Exploratory Study Of Gold Nanoshell As A Therapeutic Thermal Ablation Agent For Cancer Treatment Using Laboratory And Animal Tissue Phantoms, Yajuvendra Rathore

Bioengineering Theses - Archive

Prostate cancer is the most common male cancer in the United States and the second leading cause of male death from cancer. Surgical removal of the prostate is associated with high risks of surgical complications and consequences such as incontinence and sexual dysfunction. In my study, I have investigated a nanoparticle-assisted photothermal therapeutic method that may be used for treatment of prostate cancer in the future. This method is minimally-invasive and uses gold nano-shells as hyperthermia agents to treat localized necrosis of cancer cells. I have conducted a feasibility study for a new class of NIR absorbing nanoparticles called Gold …


Study Of Normobaric Hyperoxia Effects During Focal Hypoxia-Ischemic Injury In Mice Using Optical Spectroscopy Measurements, Shereen Mohideen Aug 2008

Study Of Normobaric Hyperoxia Effects During Focal Hypoxia-Ischemic Injury In Mice Using Optical Spectroscopy Measurements, Shereen Mohideen

Bioengineering Theses - Archive

Optical spectroscopy has seen tremendous growth and development in recent years and has been extensively used to characterize the optical properties of biological tissues. The purpose of this study is to investigate the values of oxygen saturation and concentration of hemoglobin in mice with focal hypoxic ischemia after being recovered in normobaric hyperoxia. Mice at five different age levels were used for this purpose, in order to see the effects of hyperoxia at different developmental stages of the brain; ischemia was induced in them by ligating their right carotid artery and subjecting them to hypoxic (8% oxygen) environment for half …


Sequential Frameworks For Statistics-Based Value Function Representation In Approximate Dynamic Programming, Huiyuan Fan Aug 2008

Sequential Frameworks For Statistics-Based Value Function Representation In Approximate Dynamic Programming, Huiyuan Fan

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Dynamic programming (DP) was derived by Bellman in 1957 as a mathematical programming method to solve multistage decision problems. The DP concept has great potential, but it only can solve small problems exactly under very limiting restrictions such as linear dynamics, quadratic cost, Gaussian random variable, etc. With advances in computational power, a new family of dynamic programming known as approximate dynamic programming (ADP) has emerged. A real-world DP problem is often high-dimensional and stochastic with continuous state variables. To handle this type of problem, ADP methods discretize/sample the continuous state space and approximate the future value (or cost-to-go) function …


Life Cycle Assessment Of Bio-Material Stabilized Expansive Soils, Ranjith Samuel Rosenberk Aug 2008

Life Cycle Assessment Of Bio-Material Stabilized Expansive Soils, Ranjith Samuel Rosenberk

Civil Engineering Dissertations - Archive

Pavement cracking is one of the major maintenance works that requires millions of dollars in repair costs annually. Pavement cracks are formed due to moisture and temperature fluctuations in the soil. Stabilization of pavement shoulder subsoil with the addition of compost material was studied for preventing pavement cracks. Eight different compost materials with three major feed stock sources such as biosolids, wood waste, and animal manure were investigated in this research. Compost treatment studies were performed at four different test sites located in various regions of the state of Texas. Laboratory experiments were conducted completed compost manufactured topsoil's (CMTs) to …


Issues On Stability Of Adp Feedback Controllers For Dynamical Systems, S. N. Balakrishnan, Jie Ding, F. L. Lewis Aug 2008

Issues On Stability Of Adp Feedback Controllers For Dynamical Systems, S. N. Balakrishnan, Jie Ding, F. L. Lewis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper traces the development of neural-network (NN)-based feedback controllers that are derived from the principle of adaptive/approximate dynamic programming (ADP) and discusses their closed-loop stability. Different versions of NN structures in the literature, which embed mathematical mappings related to solutions of the ADP-formulated problems called “adaptive critics” or “action-critic” networks, are discussed. Distinction between the two classes of ADP applications is pointed out. Furthermore, papers in “model-free” development and model-based neurocontrollers are reviewed in terms of their contributions to stability issues. Recent literature suggests that work in ADP-based feedback controllers with assured stability is growing in diverse forms.


Microwave Dielectroscopy Of Breast Tissue Phantoms In The 5.8-40 Ghz Range, Binh Tran Aug 2008

Microwave Dielectroscopy Of Breast Tissue Phantoms In The 5.8-40 Ghz Range, Binh Tran

Electrical Engineering Undergraduate Honors Theses

Based on the high contrast in dielectric properties between the low-water-contain sample and the high-water-content one, we can determine whether the tissue sample is cancerous or normal. In order to make the measurement repeatable and convenient, some phantom materials, which have the same dielectric properties of human tissues, have been prepared. These phantom tissues are made from gelatin, water with honey syrup and Sodium Chloride (NaCl). In this project, we are going to measure and compare the dielectric properties of different types of phantom tissues by using focused beam antennas. The purpose of this project is to perform a systematic …


Maximum Likelihood Methods In Biology Revisited With Tools Of Computational Intelligence, John E. Seiffertt Iv, Andrew Vanbrunt, Donald C. Wunsch Aug 2008

Maximum Likelihood Methods In Biology Revisited With Tools Of Computational Intelligence, John E. Seiffertt Iv, Andrew Vanbrunt, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

We investigate the problem of identification of genes correlated with the occurrence of diseases in a given population. The classical method of parametric linkage analysis is combined with newer tools and results are achieved on a model problem. This traditional method has advantages over non-parametric methods, but these advantages have been difficult to realize due to their high computational cost. We study a class of Evolutionary Algorithms from the Computational Intelligence literature which are designed to cut such costs considerably for optimization problems. We outline the details of this algorithm, called Particle Swarm Optimization, and present all the equations and …


Analysis Of Non Load Bearing Two Component (2k) Adhesives; Under The Automotive Hemming Process Variations; Thermogravimetric, Calorimetric And Composition Analyses, Kameswara Nara Jul 2008

Analysis Of Non Load Bearing Two Component (2k) Adhesives; Under The Automotive Hemming Process Variations; Thermogravimetric, Calorimetric And Composition Analyses, Kameswara Nara

All Theses

The work focuses on the analysis of non-load bearing, two component adhesives used in joining the automotive closures. The study is concerned with the thermo-gravimetric and the calorimetric attributes of the 2K adhesive. The study includes the impact of the robotic applicators capability, in terms of the mixing ratio between the resin and the hardener, and the mechanical mixing quality. A Fourier Transform Infrared Spectroscopy (FTIR) procedure analyzes the adhesive chemical groups and tracks the growth and decay of the hydroxyl and epoxy peaks. Additionally, the cure-rate based on a reaction-type, is investigated through a Differential Scanning Calorimetry (DSC). The …


Investigation Of A Photosynthetically Aerated Cathode In A Mfc, Derek Little Jul 2008

Investigation Of A Photosynthetically Aerated Cathode In A Mfc, Derek Little

All Theses

A microbial fuel cell (MFC) creates an environment that facilitates the conversion of electron donor compounds into electrical current through the oxidizing powers of microbial growth. Within the anode of a MFC bacteria grow oxidizing organic compounds while in the cathode oxygen is reduced. The goal of a MFC is to achieve respiration under anaerobic conditions having electrodes serve as intermediate electron acceptor for bacteria in the anode and shuttle electrons through a circuit to the cathode reducing a terminal electron acceptor.
Waste from the biological production of hydrogen from agricultural peach was explored for use within the anode of …


Experimental Framework For The Position Control Of Magnetic Microfibers, Sriram Ravindren Jul 2008

Experimental Framework For The Position Control Of Magnetic Microfibers, Sriram Ravindren

All Theses

Magnetic microfibers have been developed in recent years with potential applications to a large number of fields, from MEMS to microfluidics to bio-chemical analyses. Magnetic microfibers based on polymer material like polypropylene and cellulose has been developed at Clemson University that are hollow cylindrical filaments internally coated with superparamagnetic nanoparticles. This internal coating provides the fiber with magnetic properties that allow them to be externally controlled using magnetic fields from a distance. These fibers can align with the external magnetic fields under constraints imposed by elastic properties and boundary conditions. Current work in this field is primarily focused on the …


The Development Of A Computational Model Of Thrombosis In Hemodialysis Catheters, Daniel J. Lattin Jul 2008

The Development Of A Computational Model Of Thrombosis In Hemodialysis Catheters, Daniel J. Lattin

Theses and Dissertations

Thromboembolism (TE) significantly limits the usefulness and safety of blood-contacting devices such as hemodialysis catheters. Computer simulation of TE can provide understanding of the process and can facilitate the design of more effective devices. Previous work conducted at BYU successfully modeled TE in a simple, two-dimensional flow cell design by adding quantitative TE code to a commercial computational fluid dynamics (CFD) package, Fluent. This two-dimensional model predicted thrombus initiation and growth and adjusted flow to accommodate thrombus geometries, but was limited by computational power and unsophisticated meshing techniques. To build upon this work, and take advantage of BYU's new supercomputing …


Risedronate Prevents Early Bone Loss Resulting From Whole-Body Irradiation, Eric Livingston Jul 2008

Risedronate Prevents Early Bone Loss Resulting From Whole-Body Irradiation, Eric Livingston

All Theses

Osteoporosis is a condition characterized by a reduction in bone strength resulting in an overall increase in the risk of fracture. There are many factors that contribute to the development of this condition, including ionizing radiation exposure. Declines in bone volume and trabecular micro-architecture have been found following exposure to multiple types of radiation. Past research has implicated reduction of osteoblast function and changes to vasculature as the primary sources of bone deterioration. Recently, an early increase in osteoclast number was observed following exposure to low-energy X-rays, identifying an increase in resorption as a possible cause and potential target for …


Fecal Coliform Source Identification Using Chemical Tracers, Nicole Fahrenfeld Jul 2008

Fecal Coliform Source Identification Using Chemical Tracers, Nicole Fahrenfeld

All Theses

Fecal sterols and fluorinated whitening agents (FWA) were used as chemical tracers for fecal coliform source tracking in Cane and Little Cane creeks in Walhalla, SC. Fecal sterols were quantifiable in both stream sediments and suspended particulates using an extraction, clean-up, and analytical method modified from Isobe et al. (2002) with a N,O-Bis(trimethylsilyl)trifluoroacetamide (BSTFA) derivatization scheme. Only human sterol source identification ratios were able to be calculated using the chosen sterol suite. Human fecal signatures were seen in both the sediment and the water column at various points along both creeks, indicating human fecal pollution is contributing to the fecal …


Investigation Of The Discharge Coefficient For Circular Orifices In Riser Pipes, David Prohaska Jul 2008

Investigation Of The Discharge Coefficient For Circular Orifices In Riser Pipes, David Prohaska

All Theses

The purpose of this study is to examine the discharge coefficient as it pertains to
flow through a circular orifice cut into a thin-walled vertical riser pipe. Perforated riser
pipes are a popular outlet control structure for stormwater detention basins. These
basins are used to store and release stormwater runoff from impervious areas of
developed sites. Federal, state, and local regulatory agencies provide requirements for
the quality of stormwater runoff, as well as the maximum peak discharges from a
developed site. Accurately determining the flow rate from a perforated vertical riser
pipe is crucial to meeting these requirements and protecting …


Biomechanical Evaluation Of Two Methods Of Humeral Shaft Fixation, Joshua Catanzarite Jul 2008

Biomechanical Evaluation Of Two Methods Of Humeral Shaft Fixation, Joshua Catanzarite

All Theses

Biomechanical evaluations of fracture fixation devices attempt to determine implant performance by approximating the in vivo conditions. This performance is affected by many factors and relies on the complex bone-implant interface. Biomechanical tests can be designed in a variety of ways in order to evaluate device performance with respect to any number of these bone-implant interactions. Standardized tests, designed by groups such as the American Society for Testing and Materials (ASTM), are often designed either to determine the performance of a specific type of fixation device or for direct comparison between different devices. Additionally, many biomechanical evaluations are designed for …