The construction and optimization of a surface plasmon resonance sensor for the studies of bio-molecular interactions

Bio-molecular interactions exist ubiquitously in all biological systems. This dissertation project was to construct a powerful surface plasmon resonance (SPR) sensor. The SPR system is used to study bio-molecular interactions in real time and without labeling. Surface plasmon is the oscillation of free electrons in metals coupled with surface electromagnetic waves. These surface electromagnetic waves provide a sensitive probe to study bio-molecular interactions on metal surfaces. This project resulted in the successful construction and optimization of a homemade SPR sensor and the development of several new powerful protocols to study bio-molecular interactions. It was discovered through this project that the limitations of earlier SPR sensors are related not only to the instrumentation design and operating procedures, but also to the complex behaviors of bio-molecules on sensor surfaces that were very different from that in solution. Based on these discoveries the instrumentation design and operating procedures were fully optimized. A set of existing sensor surface treatment protocols were tested and evaluated and new protocols were developed in this project. The new protocols have demonstrated excellent performance to study biomolecular interactions. The optimized home-made SPR sensor was used to study protein-surface interactions. These protein-surface interactions are responsible for many complex organic cell activities. The co-existence of different driving forces and their correlation with the structure of the protein and the surface make the understanding of the fundamental mechanism of protein-surface interactions a very challenging task. Using the improved SPR sensor, the electrostatic interaction and hydrophobic interaction were studied separately. The results of this project directly confirmed the theoretical predictions for electrostatic force between the protein and surface. In addition, this project demonstrated that the strength of the protein-surface hydrophobic interaction does not solely depend on the hydrophobicity as reported earlier. Surface structure also plays a significant role.

The discursive construction of Japanese identity and its haunting others

This dissertation examined the formation of Japanese identity politics after World War II. Since World War II, Japan has had to deal with a contradictory image of its national self. On the one hand, as a nation responsible for colonizing fellow Asian countries in the 1930s and 1940s, Japan has struggled with an image/identity as a regional aggressor. On the other hand, having faced the harsh realities of defeat after the war, Japan has seen itself depicted as a victim. By employing the technique of discourse analysis as a way to study identity formation through official foreign policy documents and news media narratives, this study reconceptualized Japanese foreign policy as a set of discursive practices that attempt to produce renewed images of Japan's national self. The dissertation employed case studies to analyze two key sites of Japanese postwar identity formation: (1) the case of Okinawa, an island/territory integral to postwar relations between Japan and the United States and marked by a series of US military rapes of native Okinawan girls; and (2) the case of comfort women in Japan and East Asia, which has led to Japan being blamed for its wartime sexual enslavement of Asian women. These case studies found that it was through coping with the haunting ghost of its wartime past that Japan sought to produce "postwar Japan" as an identity distinct from "wartime imperial Japan" or from "defeated, emasculated Japan" and, thus, hoped to emerge as a "reborn" moral and pacifist nation. The research showed that Japan struggled to invent a new self in a way that mobilized gendered dichotomies and, furthermore, created "others" who were not just spatially located (the United States, Asian neighboring nations) but also temporally marked ("old Japan"). The dissertation concluded that Japanese foreign policy is an ongoing struggle to define the Japanese national self vis-à-vis both spatial and historical "others," and that, consequently, postwar Japan has always been haunted by its past self, no matter how much Japan's foreign policy discourses were trying to make this past self into a distant or forgotten other.

Research-to-Practice (R2P) Tools for Improving Safety in Nighttime Highway Construction Work Zones

The safety of workers in nighttime roadway work zones has become a major concern for state transportation agencies due to the increase in the number of work zone fatalities. During the last decade, several studies have focused on the improvement of safety in nighttime roadway work zones; but the element that is still missing is a set of tools for translating the research results into practice. This paper discusses: 1) the importance of translating the research results related to the safety of workers and safety planning of nighttime work zones into practice, and 2) examples of tools that can be used for translating the results of such studies into practice. A tool that can propose safety recommendations in nighttime work zones and a web-based safety training tool for workers are presented in this paper. The tools were created as a component of a five-year research study on the assessment of the safety of nighttime roadway construction. The objectives of both tools are explained as well as their functionalities (i.e., what the tools can do for the users); their components (e.g., knowledge base, database, and interfaces); and their structures (i.e., how the components of the tools are organized to meet the objectives). Evaluations by the proposed users of each tool are also presented.

A model for continuous measurement of drilled shaft diameter during construction

Non-Destructive Testing (NDT) of deep foundations has become an integral part of the industry's standard manufacturing processes. It is not unusual for the evaluation of the integrity of the concrete to include the measurement of ultrasonic wave speeds. Numerous methods have been proposed that use the propagation speed of ultrasonic waves to check the integrity of concrete for drilled shaft foundations. All such methods evaluate the integrity of the concrete inside the cage and between the access tubes. The integrity of the concrete outside the cage remains to be considered to determine the location of the border between the concrete and the soil in order to obtain the diameter of the drilled shaft. It is also economic to devise a methodology to obtain the diameter of the drilled shaft using the Cross-Hole Sonic Logging system (CSL). Performing such a methodology using the CSL and following the CSL tests is performed and used to check the integrity of the inside concrete, thus allowing the determination of the drilled shaft diameter without having to set up another NDT device.^ This proposed new method is based on the installation of galvanized tubes outside the shaft across from each inside tube, and performing the CSL test between the inside and outside tubes. From the performed experimental work a model is developed to evaluate the relationship between the thickness of concrete and the ultrasonic wave properties using signal processing. The experimental results show that there is a direct correlation between concrete thicknesses outside the cage and maximum amplitude of the received signal obtained from frequency domain data. This study demonstrates how this new method to measuring the diameter of drilled shafts during construction using a NDT method overcomes the limitations of currently-used methods. ^ In the other part of study, a new method is proposed to visualize and quantify the extent and location of the defects. It is based on a color change in the frequency amplitude of the signal recorded by the receiver probe in the location of defects and it is called Frequency Tomography Analysis (FTA). Time-domain data is transferred to frequency-domain data of the signals propagated between tubes using Fast Fourier Transform (FFT). Then, distribution of the FTA will be evaluated. This method is employed after CSL has determined the high probability of an anomaly in a given area and is applied to improve location accuracy and to further characterize the feature. The technique has a very good resolution and clarifies the exact depth location of any void or defect through the length of the drilled shaft for the voids inside the cage. ^ The last part of study also evaluates the effect of voids inside and outside the reinforcement cage and corrosion in the longitudinal bars on the strength and axial load capacity of drilled shafts. The objective is to quantify the extent of loss in axial strength and stiffness of drilled shafts due to presence of different types of symmetric voids and corrosion throughout their lengths.^

Intelligent retrieval system for conditions of contract documents in construction

The outcome of this research is an Intelligent Retrieval System for Conditions of Contract Documents. The objective of the research is to improve the method of retrieving data from a computer version of a construction Conditions of Contract document. SmartDoc, a prototype computer system has been developed for this purpose. The system provides recommendations to aid the user in the process of retrieving clauses from the construction Conditions of Contract document. The prototype system integrates two computer technologies: hypermedia and expert systems. Hypermedia is utilized to provide a dynamic way for retrieving data from the document. Expert systems technology is utilized to build a set of rules that activate the recommendations to aid the user during the process of retrieval of clauses. The rules are based on experts knowledge. The prototype system helps the user retrieve related clauses that are not explicitly cross-referenced but, according to expert experience, are relevant to the topic that the user is interested in.

The Discursive Construction of Japanese Identity and its Haunting Others

This dissertation examined the formation of Japanese identity politics after World War II. Since World War II, Japan has had to deal with a contradictory image of its national self. On the one hand, as a nation responsible for colonizing fellow Asian countries in the 1930s and 1940s, Japan has struggled with an image/identity as a regional aggressor. On the other hand, having faced the harsh realities of defeat after the war, Japan has seen itself depicted as a victim. By employing the technique of discourse analysis as a way to study identity formation through official foreign policy documents and news media narratives, this study reconceptualized Japanese foreign policy as a set of discursive practices that attempt to produce renewed images of Japan’s national self. The dissertation employed case studies to analyze two key sites of Japanese postwar identity formation: (1) the case of Okinawa, an island/territory integral to postwar relations between Japan and the United States and marked by a series of US military rapes of native Okinawan girls; and (2) the case of comfort women in Japan and East Asia, which has led to Japan being blamed for its wartime sexual enslavement of Asian women. These case studies found that it was through coping with the haunting ghost of its wartime past that Japan sought to produce “postwar Japan” as an identity distinct from “wartime imperial Japan” or from “defeated, emasculated Japan” and, thus, hoped to emerge as a “reborn” moral and pacifist nation. The research showed that Japan struggled to invent a new self in a way that mobilized gendered dichotomies and, furthermore, created “others” who were not just spatially located (the United States, Asian neighboring nations) but also temporally marked (“old Japan”). The dissertation concluded that Japanese foreign policy is an ongoing struggle to define the Japanese national self vis-à-vis both spatial and historical “others,” and that, consequently, postwar Japan has always been haunted by its past self, no matter how much Japan’s foreign policy discourses were trying to make this past self into a distant or forgotten other.

A Model for Continuous Measurement of Drilled Shaft Diameter During Construction

Non-Destructive Testing (NDT) of deep foundations has become an integral part of the industry’s standard manufacturing processes. It is not unusual for the evaluation of the integrity of the concrete to include the measurement of ultrasonic wave speeds. Numerous methods have been proposed that use the propagation speed of ultrasonic waves to check the integrity of concrete for drilled shaft foundations. All such methods evaluate the integrity of the concrete inside the cage and between the access tubes. The integrity of the concrete outside the cage remains to be considered to determine the location of the border between the concrete and the soil in order to obtain the diameter of the drilled shaft. It is also economic to devise a methodology to obtain the diameter of the drilled shaft using the Cross-Hole Sonic Logging system (CSL). Performing such a methodology using the CSL and following the CSL tests is performed and used to check the integrity of the inside concrete, thus allowing the determination of the drilled shaft diameter without having to set up another NDT device. This proposed new method is based on the installation of galvanized tubes outside the shaft across from each inside tube, and performing the CSL test between the inside and outside tubes. From the performed experimental work a model is developed to evaluate the relationship between the thickness of concrete and the ultrasonic wave properties using signal processing. The experimental results show that there is a direct correlation between concrete thicknesses outside the cage and maximum amplitude of the received signal obtained from frequency domain data. This study demonstrates how this new method to measuring the diameter of drilled shafts during construction using a NDT method overcomes the limitations of currently-used methods. In the other part of study, a new method is proposed to visualize and quantify the extent and location of the defects. It is based on a color change in the frequency amplitude of the signal recorded by the receiver probe in the location of defects and it is called Frequency Tomography Analysis (FTA). Time-domain data is transferred to frequency-domain data of the signals propagated between tubes using Fast Fourier Transform (FFT). Then, distribution of the FTA will be evaluated. This method is employed after CSL has determined the high probability of an anomaly in a given area and is applied to improve location accuracy and to further characterize the feature. The technique has a very good resolution and clarifies the exact depth location of any void or defect through the length of the drilled shaft for the voids inside the cage. The last part of study also evaluates the effect of voids inside and outside the reinforcement cage and corrosion in the longitudinal bars on the strength and axial load capacity of drilled shafts. The objective is to quantify the extent of loss in axial strength and stiffness of drilled shafts due to presence of different types of symmetric voids and corrosion throughout their lengths.