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2009

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Inter-Tube Bonding And Defects In Carbon Nanotubes And The Impact On The Transport Properties And Micro-Morphology, Keqin Yang Dec 2009

Inter-Tube Bonding And Defects In Carbon Nanotubes And The Impact On The Transport Properties And Micro-Morphology, Keqin Yang

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The transport properties of the carbon nanotubes (CNTs) are affected by the tube-tube interaction and the defects presented in the system. Inter-tube bonding, formed during spark plasma sintering (SPS) process, lowers the electrical/thermal resistivity at the tube-tube junctions and also causes new scattering mechanisms such as strong electron-phonon coupling (EPC) at low temperature. More evidences have been found by changing the SPS temperature and doping the CNTs to support the electron-phonon coupling is Kohn anomaly (KA) in as-SPSed CNTs. The phonon drag, appearing in thermoelectric power (TEP) of the as-SPSed CNTs at low temperature, can be explained in the framework …

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Creation Of Bioactive Surfaces To Modulate Cell Behavior Using Surface Initiated Photoiniferter-Mediated Graft Photopolymerization, Nihar Shah Dec 2009

Creation Of Bioactive Surfaces To Modulate Cell Behavior Using Surface Initiated Photoiniferter-Mediated Graft Photopolymerization, Nihar Shah

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Biomaterials widely used in biomedical applications still face biocompatibility issues arising from non-specific protein adsorption on the foreign surface, and the consequent undesired cell response. Emerging evidence suggests that imparting specific bioactivity to the biomaterial's surface to elicit favorable response from cells, (like osseointegration of joint implants and endothelialization of stents) can yield much better biocompatibility results when combined with passive prevention of protein adsorption. In more complex diseases like spinal cord injury and cardiomyopathy, specific biomolecules are required to elicit desired cell responses for successful regeneration. However, for success of such biomolecule based strategies, the effects of various parameters …

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Metal Oxide And Mercuric Sulfide Nanoparticles Synthesis And Characterization, Xin Xu Dec 2009

Metal Oxide And Mercuric Sulfide Nanoparticles Synthesis And Characterization, Xin Xu

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Increasing applications of nanoparticles (NPs), such as metal oxide and mercuric sulfide NPs, lead to heightened environmental concern. Challenges to the study of natural and engineered NPs include the physical and chemical characterizations.
Commercially available and laboratory-synthesized metal based NPs, iron oxide (Fe2O3), copper oxide (CuO), titanium dioxide (TiO2), zinc oxide (ZnO) and mercuric sulfide (HgS) were studied by comprehensive characterizations methods. The general synthesis process was modified sol-gel method. The size and morphology of NPs could be influenced by temperature, sonication, calcination, precursor concentration, pH and types of reaction media. In the synthesis of nZnO in ethanol, the essential …

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Real-Time Vehicle Parameter Estimation And Adaptive Stability Control, John Limroth Dec 2009

Real-Time Vehicle Parameter Estimation And Adaptive Stability Control, John Limroth

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This dissertation presents a novel Electronic Stability Control (ESC) strategy that is capable of adapting to changing vehicle mass, tire condition and road surface conditions. The benefits of ESC are well understood with regard to assisting drivers to maintain vehicle control during extreme handling maneuvers or when extreme road conditions such as ice are encountered. However state of the art ESC strategies rely on known and invariable vehicle parameters such as vehicle mass, yaw moment of inertia and tire cornering stiffness coefficients. Such vehicle parameters may change over time, especially in the case of heavy trucks which encounter widely varying …

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Decoding Of Multipoint Algebraic Geometry Codes Via Lists, Nathan Drake Dec 2009

Decoding Of Multipoint Algebraic Geometry Codes Via Lists, Nathan Drake

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Algebraic geometry codes have been studied greatly since their introduction by Goppa . Early study had focused on algebraic geometry codes CL(D;G) where G was taken to be a multiple of a single point. However, it has been shown that if we allow G to be supported by more points, then the associated code may have better parameters. We call such a code a multipoint code and if G is supported by m points, then we call it an m-point code. In this dissertation, we wish to develop a decoding algorithm for multipoint codes. We show how we can embed …

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The Development Of A Mesenchymal Stem Cell Based Bone Graft System, Sarina Sinclair Dec 2009

The Development Of A Mesenchymal Stem Cell Based Bone Graft System, Sarina Sinclair

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Greater than 5.5 million fractures are sustained by Americans each year, accounting for more than 500,000 bone graft surgeries. Bone grafts are the second most transplanted material, surpassed only by blood. The current 'gold standard' for bone grafting involves harvesting bone material from the patient's iliac crest, due to its osteoinductive properties. Unfortunately, the surgery required to harvest material from the iliac crest causes additional pain for the patient, relies on a limited amount of available bone tissue, and results in, on average, a 30% rate of donor site morbidity. Both natural and synthetic substitutes have been developed to avoid …

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The Influence Of International Service-Learning On Cultural Competence In Baccalaureate Nursing Graduates And Their Subsequent Nursing Practice, Roxanne Amerson Dec 2009

The Influence Of International Service-Learning On Cultural Competence In Baccalaureate Nursing Graduates And Their Subsequent Nursing Practice, Roxanne Amerson

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A series of research studies was completed over 3 years to evaluate baccalaureate nursing students' transcultural self-efficacy following the completion of service-learning projects. A quantitative pilot study was completed in 2007 with a convenience sample of students (n=60) enrolled in a community health nursing course. Several clinical groups worked with local communities and one clinical group took part in a one-week program in Guatemala. The Transcultural Self-Efficacy Tool (TSET) was administered at the beginning and completion of the semester. A paired-samples t test demonstrated a significant increase for pre-test to post-test total and subscale scores.
A follow-up field study was …

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Atom Scattering From Metals, William Hayes Dec 2009

Atom Scattering From Metals, William Hayes

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In the initial portion of this dissertation studies of Ar
scattering from Ru(0001) at thermal and hyperthermal energies are
compared to calculations with classical scattering theory. These
data exhibited a number of characteristics that are unusual in
comparison to other systems for which atomic beam experiments have
been carried out under similar conditions. The measured energy
losses were unusually small. Some of the angular distributions
exhibited an anomalous shoulder feature in addition to a broad
peak near the specular direction and quantum mechanical
diffraction was observed under conditions for which it was not
expected. Many of the unusual features observed …

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Prevalence And Biological Control Of Salmonella Contamination In Rendering Plant Environments And The Finished Rendered Meals, Brandon Kinley Dec 2009

Prevalence And Biological Control Of Salmonella Contamination In Rendering Plant Environments And The Finished Rendered Meals, Brandon Kinley

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Although the rendering process serves as invaluable means for the disposal of inedible animal by-products, the finished products often harbor pathogenic and opportunistic microorganisms such as Salmonella and enterococci, respectively. The temperatures used during the rendering process far exceed the heat tolerance threshold of most bacterial species, so cross-contamination from the environment and/or from the incoming raw material is the proposed source of the contamination. Research has demonstrated that the raw material coming into the rendering facility is highly contaminated with pathogenic bacteria including Salmonella. While not in a rendering facility, studies have also demonstrated that bacteria such as Salmonella …

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Dynamics Of Ultrasonic Consolidation, James Gibert Dec 2009

Dynamics Of Ultrasonic Consolidation, James Gibert

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Ultrasonic consolidation (UC) is a solid state rapid manufacturing process derived from ultrasonic welding of thin metal foils coupled with contour milling to achieve functional accurate components. The bonding of metal is accomplished by the local application of high frequency vibration energy under pressure producing a metallurgical bond without melting the base material. Its unique nature allows the design and fabrication of structural panels for satellites, production of injection molding tools, functionally graded structures, metal-matrix composites, embedded sensors, armor, and fiber embedded adaptive structures. It is commonly theorized that interfacial motion and friction at the bonding interface play a prominent …

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Characterization Of Escherichia Coli Related To Construction Site Sediment Basins, Calvin Sawyer Dec 2009

Characterization Of Escherichia Coli Related To Construction Site Sediment Basins, Calvin Sawyer

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Large construction sites can have significant temporary and permanent impacts on the physical landscape. Excess sediment is frequently deposited into nearby surface waters, altering benthic habitat, reducing water clarity and transporting other pollutants such as enteric bacteria. To capture eroded soil and attenuate storm discharge peaks, many permitted construction projects larger than 10 acres in South Carolina require the installation of a sediment basin. Sediment-laden runoff is routed to a newly excavated impoundment, where larger particles settle out of suspension. Thus an entirely new hydrologic feature designed to concentrate eroded sediment and water is introduced into the landscape.
Eight construction …

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A Partnership Based Approach To Professional Learning: Pre-Service And In-Service Teachers Working Together To Teach Primary Science, John Kenny Dec 2009

A Partnership Based Approach To Professional Learning: Pre-Service And In-Service Teachers Working Together To Teach Primary Science, John Kenny

Australian Journal of Teacher Education

This paper reports on a partnership based approach for preparing pre-service primary teachers to teach science. It involved forming three-way or "triadic" partnerships, consisting of a final year pre-service primary teacher and an in-service colleague, to teach science in the colleague teacher’s classroom, with the support of a teacher-educator. The pre-service teachers had to collaboratively plan, develop and deliver a sequence of science lessons and take major responsibility for teaching a 90 minute science lesson, at least once a week over a six week period. The data was collected during 2007 and 2008. The pre-service teachers kept a reflective journal …

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‘Motivation In Action’ In A Collaborative Primary Classroom: Developing And Sustaining Teacher Motivation, Veronica Morcom, Judith Maccallum Dec 2009

‘Motivation In Action’ In A Collaborative Primary Classroom: Developing And Sustaining Teacher Motivation, Veronica Morcom, Judith Maccallum

Australian Journal of Teacher Education

This paper examines how the process of scaffolding students to solve their social issues developed mature participation for both the teacher and students. A sociocultural perspective framed the research as the underlying assumption is that students learn from each other, mediated by the teacher or more capable peers. The study provides evidence that teachers play a significant role in mediating positive relationships amongst peers, which in this case, sustained the teacher’s motivation to engage in the challenging and at times exhausting process. The teacher used weekly class meetings to negotiate with students how to share ‘power’ and model democratic decision-making. …

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L2 Teachers’ Pedagogic Knowledge Base: A Comparison Between Experienced And Less Experienced Practitioners, Ramin Akbari, Leila Tajik Dec 2009

L2 Teachers’ Pedagogic Knowledge Base: A Comparison Between Experienced And Less Experienced Practitioners, Ramin Akbari, Leila Tajik

Australian Journal of Teacher Education

Second language teacher education community has become increasingly interested in the pedagogical knowledge base of teachers as a window into practitioners' mental lives. The present study was conducted to document likely differences between the pedagogic thoughts of experienced and less experienced teachers. Eight teachers participated in the project. Data were collected through the use of stimulated recall. The analysis of the data shows that there are differences both in the number and the order of the thoughts teachers produced in different groups. Experienced teachers produced an average of five pedagogical thoughts per minute, while their less experienced counterparts produced 3 …

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Configuring Of Masculinity In An Ethnocentric Community School, Dimitri Garas, Sally Godinho Dec 2009

Configuring Of Masculinity In An Ethnocentric Community School, Dimitri Garas, Sally Godinho

Australian Journal of Teacher Education

This paper presents snapshots of a qualitative study that investigated how Year 8 boys in an ethnocentric community school configured their constructions of masculinity. Fifteen boys participated in focus group discussions that extended over a six-week period. For one focus group, the boys were invited to bring a ‘totem’, which was an embodiment of their masculinity. The findings from the focus groups revealed both collective and individual constructions and enactments of masculinities that were talked into existence and transmitted through hegemonic discourses. Yet the findings also revealed the boys’ individual agency to engage with other ways of doing and being …

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Teaching Out-Of-Field In Western Australia, Andrew Mcconney, Anne Price Dec 2009

Teaching Out-Of-Field In Western Australia, Andrew Mcconney, Anne Price

Australian Journal of Teacher Education

A former head of the American Federation of Teachers, Albert Shanker, once called out-of-field teaching education’s “dirty little secret” (Ingersoll, 2003, p. 5). The practice of allowing or assigning teachers to teach subjects or year levels for which they do not have any formal qualifications has lead to considerable debate within the educational community. Such concerns over the possible negative impact of out-of-field teaching on students, teachers and the broader school community led the Western Australian College of Teaching (WACOT) to commission an exploratory empirical study of the extent of the phenomenon in Western Australia. This paper presents the main …

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Design And Implementation Of Proposed B-R Encryption Algorithm, Janan Ateya Dec 2009

Design And Implementation Of Proposed B-R Encryption Algorithm, Janan Ateya

Iraqi Journal of Computers, Communications, Control and Systems Engineering

In this paper, a 128-bit block cipher B-R encryption algorithm is proposed which is an eVolutionary improvement of 64-bits Blowfish designed to meet the requirements of the Advanced Encryption Standard. It is compact, speedy, simple and easy to understand. It is a Feistel network, iterating a simple encryption function 16 times and the key can be any length up to 128 bytes. The B-R reduced the memory requirement by using two S-boxes each of which of size 259 bytes instead of four S-boxes each of size 1024 bytes in Blowfish algorithm ,so that the total size of S-box of B-R …

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Automatic Extracted Object Technique For Contrast Enhancement Medical Images, Raffia's Talib, Atheer Jabbar Mansor Dec 2009

Automatic Extracted Object Technique For Contrast Enhancement Medical Images, Raffia's Talib, Atheer Jabbar Mansor

Iraqi Journal of Computers, Communications, Control and Systems Engineering

The aim of this work is a proposed system to enhance automatically the contrast of the desired region in the medical image to get the wanted information without enhancing the contrast of the whole image. The proposed system includes the automatic extraction process, the automatic contrast enhancement process and finally reinsertion process for region in the image. Threshold, smoothing, boundary extraction, chain code or region filling techniques were used in the automatic extraction process. While, histogram equalization, histogram stretching, gray level grouping (GLG), fast gray level grouping (FGLG) or auto-contrast techniques were used in the automatic contrast enhancement process for …

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Design And Implementation Of An Improvement Of Blowfish Encryption Algorithm, Ashwaq T., Saleh M. Al-Qarrawy, Janan A. Mahdi Dec 2009

Design And Implementation Of An Improvement Of Blowfish Encryption Algorithm, Ashwaq T., Saleh M. Al-Qarrawy, Janan A. Mahdi

Iraqi Journal of Computers, Communications, Control and Systems Engineering

Block cipher is a major part of cipher algorithm like stream cipher and other techniques. Its power comes from dealing with plaintext as parts and operating on each block independently. Blowfish is a secret-key block cipher proposed by B. Shneier. It is a Feistel network, iterating a simple encryption function 16 times. The block size is 8-bytes and the key can be any length up to 56-bytes. In this paper, a Blowfish was improved to encrypt 16-bytes using a variable key length from 8-bytes up to 144-bytes. During the design of Improved Blowfish algorithm, the pragmatic aim was to satisfy …

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Error Estimation For An Integrated Gps/Ins System Using Adaptive Neuro-Fuzzy Technique, Salam A., Ahmed M. Hassan, Ali F. Lutfy Dec 2009

Error Estimation For An Integrated Gps/Ins System Using Adaptive Neuro-Fuzzy Technique, Salam A., Ahmed M. Hassan, Ali F. Lutfy

Iraqi Journal of Computers, Communications, Control and Systems Engineering

Global Positioning System (GPS) and Strap down Inertial Navigation System (SDINS) can be Integrated Together To Provide A Reliable Navigation System. In This Paper, A Technique For Error Estimation In A GPS/INS System Based On A Low-Cost Inertial Measurement Unit (IMU) Is Offered. This Technique Is Composed Of Wavelet Transform (WT) And Adaptive Fuzzy System (AFS). The Wavelet Decomposition Is Used To De-Noise The Position And Velocity Components Of The GPS And INS Outputs. An AFS Is Introduced In This Paper To Estimate The Position And Velocity Errors In The Integrated System In Order To Provide Accurate Navigation Information About …

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A Lab View Based Data Acquisition System For Radial Temperature Distribution, Ahmed Mudher, Hazem I. Ali, Ali Farooq Lutfi Dec 2009

A Lab View Based Data Acquisition System For Radial Temperature Distribution, Ahmed Mudher, Hazem I. Ali, Ali Farooq Lutfi

Iraqi Journal of Computers, Communications, Control and Systems Engineering

Lab VIEW (Laboratory Virtual Instrument Engineering Workbench) is gaining its popularity as a graphical programming language especially for data acquisition and measurement. This is due to the vast array of data acquisition cards and measurement systems which can be supported by LabVIEW as well as the relative ease by which advanced software can be programmed. One area of application of LabVEW is in the measuring and analyzing of radial temperature distribution. This paper describes a LabVIEW based data acquisition and analysis developed specifically for radial temperature distribution. The temperature is simultaneously measured and displayed.

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Design Of A Stochastic Re-Configurable Artificial Neural Networks Using Fpga, Mutaz S., Hannan A. R. Akkar, Manal H. Jassim Dec 2009

Design Of A Stochastic Re-Configurable Artificial Neural Networks Using Fpga, Mutaz S., Hannan A. R. Akkar, Manal H. Jassim

Iraqi Journal of Computers, Communications, Control and Systems Engineering

This paper uses the theory of stochastic arithmetic as a solution for the FPGA implementation of a complex feed forward, multi layered neural network. Compared with the traditional digital implementations, the stochastic approach simplifies the computation inVolved and saves digital resources. The architecture combines stochastic computation techniques with a novel Look Up-Table-based that fully exploits the Look Up-Table structure of many FPGAs. Basic operations of simple ANN are mapped into a modular design. The system control module, random pulse generating module , bit stream generating module , LFSR_32(Liner Feedback Shift Register) sub module, modulator sub module, neuron module and bit …

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A Modified Bisected-T Matching Network For Microwave Filter Design, Azad Raheem Dec 2009

A Modified Bisected-T Matching Network For Microwave Filter Design, Azad Raheem

Iraqi Journal of Computers, Communications, Control and Systems Engineering

In this paper, a proposed method to implement the image parameter filters is presented. It is based on cascading π-networks and using a proposed bisected-T m-derived matching section to the source and load impedances instead of the use of the cascaded T-networks and the classical bisected-π matching sections. The proposed method achieves the advantage of reducing the total number of the inductors in the circuit which is a great benefit for circuit implementation in the recent monolithic microwave integrated circuit (MMIC) technology. The method also finds application in broadband microwave distributed amplifiers design.

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Implementation Of Genetic Algorithm Using Fpga With Applications, Hanan A., Omar Arif Abdul-Rahman Dec 2009

Implementation Of Genetic Algorithm Using Fpga With Applications, Hanan A., Omar Arif Abdul-Rahman

Iraqi Journal of Computers, Communications, Control and Systems Engineering

This paper presents a design of a general purpose GA. It is described using the Very high speed integrated circuits Hardware Description Language (VHDL), which is one of the Hardware Description Languages (HDLs). The complete system is implemented in a single Field Programmable Gate Array (FPGA) platform using the Foundation 2.1i, which is a software tool from XILINX. The feasibility of the purposed FPGA-based GA (FPGAGA) is demonstrated by testing it using two case studies. The objective of the first test is to maximize mathematical functions (f(x) = 2x, f(x) = x+5 and f(x) =2x3 -45x2 +300x) over the domain …

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Synthesis And Characterization Of Metallic, Core-Shell And Composite Nanoparticles, Amar Kumbhar Dec 2009

Synthesis And Characterization Of Metallic, Core-Shell And Composite Nanoparticles, Amar Kumbhar

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ABSTRACT
Silver nanoparticles exhibit size, shape and the surrounding dielectric medium dependent optical properties (scattering and absorption) in the visible spectral region. These optical properties can be explained in terms of the collective oscillation of the 'free conduction band electrons' or 'surface plasmons' induced by an external electromagnetic field. Dipole and Quadrupole Plasmon resonances have been observed for silver particles less than 100nm in diameter prepared using various synthetic techniques. However higher order resonances have been elusive due to lack of experimental techniques to prepare colloidal solutions of large silver nanoparticles in the size range above 100nm. Controlled hydrogen reduction …

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Efficient Analysis Of Loaded Cylindrical Monopole Antennas, Adam Schreiber Dec 2009

Efficient Analysis Of Loaded Cylindrical Monopole Antennas, Adam Schreiber

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In this dissertation is presented a collection of papers focusing on enhancing the efficiency of integral equation solutions of antennas. A method of incorporating network principles into the method of moments is developed. Scattering parameters are determined for two structures: a coaxial-guide/radial-guide junction present in coaxial feeds of monopole and dipole antennas, and a folded coaxial guide junction proposed as part of an inductive load below the feed of the antenna. There is excellent agreement among the data obtained from the proposed method, independent MoM solutions not incorporating network principles, and measurements. An investigation into electrically switching a folded coaxial …

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Development Of A Fluorescent Probe For Determination Of Water Transport In Subcellular Organelles, Adriana Chaurra-Arboleda Dec 2009

Development Of A Fluorescent Probe For Determination Of Water Transport In Subcellular Organelles, Adriana Chaurra-Arboleda

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Water transport has been widely studied in a variety of cells and isolated membranes. However, the intrinsic complexity related with the study of intracellular processes has delayed the development of an analytical technique for the study of water transport in subcellular compartments of living cells. This study represents the development and application of a ratiometric fluorescent probe to study water transport in endocytic organelles of intact living cells. The probe is based on the use of a D2O-sensitive fluorophore, Lucifer yellow dextran (LY-dex), together with a D2O-insensitive fluorophore, Alexa fluor 546 dextran (AF546-dex), used as an …

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An Approach Designed For Reginal Prospective Human Health And Ecological Risk Assessment And Its Application To Mercury Risks From A Coal-Fired Power Plant, Pathratipa Sansayavichai Dec 2009

An Approach Designed For Reginal Prospective Human Health And Ecological Risk Assessment And Its Application To Mercury Risks From A Coal-Fired Power Plant, Pathratipa Sansayavichai

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A large and/or long-term released source of a toxic chemical(s) can cause adverse effects to humans and non–human species inhabiting all over the region. The overall goal of this dissertation was to improve practices in risk assessment concerning a regional risk posed by a prospective source. A generic conceptual framework for performing regional prospective human health and ecological risk assessment was developed. The formulation of a priori considerations was used to identify the possible sources of uncertainties in the prospective risk assessment. Physiologically based pharmacokinetic (PBPK) modeling was utilized to reduce uncertainty in a toxicologically safe dose used in risk …

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Hydrogel Compositions For Nonviral Gene Delivery, Eunhee Cho Dec 2009

Hydrogel Compositions For Nonviral Gene Delivery, Eunhee Cho

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The incorporation of nonviral vectors into biomaterial matrices has been employed to improve localization at the implant site and to protect from loss by clearance or extracellular barriers. However, several limitations such as detrimental crosslinking mechanisms, uncontrolled burst release require improved design of matrix-based gene delivery systems that provides sustained and controlled vector release as well as overcomes extracellular barriers to gene transfer in proximity to target cells. The long-term objective of this dissertation project is to provide the basis for the eventual creation of tissue engineering scaffolds that combine structural and biological activity through the creation of composite materials …

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Interrupting The Workplace: Examining Stressors In An Information Technology Context, Pamela Galluch Dec 2009

Interrupting The Workplace: Examining Stressors In An Information Technology Context, Pamela Galluch

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This dissertation focuses on the negative and positive outcomes of information and communication technology (ICT) in facilitating and reducing stress. The goals of this dissertation are twofold: 1) to deepen our understanding of how ICT-enabled interruptions influence individuals' episodic stress and 2) to examine whether ICTs may also be used to diminish stress evoked by ICT-enabled interruptions. Originating from psychology, the demands control model (Karasek, 1979) is used as an overarching theoretical lens to explain this technology-based duality, where technology serves as both a problem causing and a solution alleviating stress. The demands control model suggests that stressors have their …

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