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Title: Investigation of Fresh Produce Washing on E. Coli O157:H7 and Murine Norovirus with Peroxyacetic Acid and High Power Ultrasound
Creator: Yuan, Wen
Date: 2011-12-05, 2011-12
Description: E. coli O157:H7 and norovirus have each been responsible for outbreaks of foodborne illness involving fresh leafy green vegetables....
Show moreE. coli O157:H7 and norovirus have each been responsible for outbreaks of foodborne illness involving fresh leafy green vegetables. Peroxyacetic acid (POAA) has the potential to be an effective sanitizer during commercial fresh-cut produce washing. The addition of high power ultrasound (HPU) to the washing system may enhance the POAA efficacy. The purpose of this study was to reduce E. coli O157:H7 and norovirus contamination during commercial fresh-cut lettuce washing using POAA and HPU. Fresh-cut romaine lettuce leaves were inoculated with E. coli O157:H7 or murine norovirus (MNV, a surrogate for the human norovirus) and washed by POAA and HPU. Cross-contamination was tested by washing clean leaves in contaminated processing water where pre-inoculated leaves were washed previously. A high level of cross-contamination (4.5-log CFU/g E. coli) occurred after uninoculated leaves were rinsed in contaminated wash water for 2 min. A subsequent 2 min wash in POAA alone or in combination with HPU reduced counts by approximately 1.2-log and 2.3-log, respectively. More than 2-log norovirus was removed from washing 2 min in either DI water or POAA. However infectious MNV washed from leaves was not detected in wash water containing POAA. Those results implied a high possibility of cross-contamination during freshproduce washing, and indicate that adding POAA and HPU in addition to washing water in wash water can reduce cross-contamination rate.
M.S. in Food Safety and Technology, December 2011
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Title: Study of the action of a four inch grinnell variable pressure alarm valve
Creator: Hotchkin, E. W., Pfaelzer, F. M
Date: 2009, 1910
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofactionoff00hotc
Thesis (B.S.)--Armour Institute of Technology, 1910 B.S. in Fire Protection Engineering,...
Show morehttp://www.archive.org/details/studyofactionoff00hotc
Thesis (B.S.)--Armour Institute of Technology, 1910 B.S. in Fire Protection Engineering, 1910
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Title: COATING OF BORON NITRIDE THIN FILM ON TITANIUM
Creator: Huang, Mairui
Date: 2013, 2013-12
Description: To improve the wear resistance of titanium and extend its service life, coating boron nitride thin films on the surface of titanium matrix was...
Show moreTo improve the wear resistance of titanium and extend its service life, coating boron nitride thin films on the surface of titanium matrix was studied in this work. To obtain surface property enhancement, the samples were coated by isothermal sintering at 1000°C – 1400°C in a vacuum furnace for 2h, 4h or 6h. The microstructure of the thin film was investigated employing X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). To identify the composition of interlayers between BN and Ti, EDS analysis was run through the whole reaction zone. It showed that the BN was being consumed, titanium borides (TiB and TiB2), titanium nitride (TiN1-x), and solid solution of nitrogen in titanium (α-Ti (N)) layers formed at the interface between the BN coating and Ti matrix. Correspondingly, the XRD analysis indicated that TiB, TiB2, TiN, and α-Ti(N) phases were presented in good agreement with the EDS result. The layers grew fast in the sintering process which benefited from the fine grain size and highly oriented layers grown in the reaction zone. However, the well-known parabolic diffusional growth is only part of mechanisms for explaining the reactiondiffusion kinetics. The diffusion paths were obtained from the phase sequences at the interface between BN and Ti and thus could be represented on the isothermal section of the B-N-Ti ternary diagram. Moreover, the influence of the sintering temperature and the length of the actual sintering period on the layer sequences and thickness of the reaction zone were investigated. The micro-hardness test results showed that the Ti matrix with deposited BN thin films exhibited significant increased surface hardness. Obviously, the surface hardness xiii rose along with sintering temperature and holding time, and the hardness could be improved over 50%.
M.S. in Materials Science and Engineering, December 2013
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Title: SIMULATING THE HESTON MODEL VIA THE QE METHOD WITH A SPECIFIED ERROR TOLERANCE
Creator: Zhao, Xiaoyang
Date: 2017, 2017-05
Description: The Quadratic Exponential (QE) model is a market standard simulation method for the Heston stochastic volatility model. We identify certain...
Show moreThe Quadratic Exponential (QE) model is a market standard simulation method for the Heston stochastic volatility model. We identify certain numerical problems with the standard discretization and modify the original method to correct these problems. We implement our modified QE scheme for the Heston model in the Guaranteed Automatic Integration Library (GAIL)|a suite of algorithms that includes Monte Carlo and quasi-Monte Carlo methods for multidimensional integration and computation of means. GAIL computes answers to satisfy user-defined error tolerances. We also implement variance reduction techniques for our modified QE scheme in GAIL. The numerical results show that our modified scheme is fast and accurate, and satisfies the user-defined error tolerances.
M.S. in Applied Mathematics, May 2017
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Title: SEISMIC STRUCTURAL ANALYSIS USING INTERVAL GROUND MOTION
Creator: Venezia, Adam
Date: 2011-12-05, 2011-12
Description: Seismic analysis is a crucial procedure for the design of a structure subjected to ground motion. In conventional seismic analysis procedures,...
Show moreSeismic analysis is a crucial procedure for the design of a structure subjected to ground motion. In conventional seismic analysis procedures, a structure is subjected to a limited number of earthquake excitations. Moreover, these procedures do not consider the presence of variations and uncertainties in those excitations. Interval analysis is one method capable of accounting for both of these limitations. In this work, a new method for seismic structural analysis, with interval uncertainty in the response spectrum, is developed, which is capable of obtaining the bounds of the dynamic response of a structure. This method is hereinafter referred to as Interval Ground Motion Analysis (IGMA). In this method, first, various response spectra are combined as an interval function, referred to as an interval response spectrum. Then, the response spectrum analysis is performed using the developed interval response spectrum, and the bounds of the dynamic response of the structure are obtained. It is shown that obtaining these bounds is computationally feasible and does not require iterative procedures such as Monte Carlo simulation. Numerical example problems, which illustrate the developed algorithm, are presented, along with a comparison of solutions obtained by another solution method.
M.S. in Civil Engineering, December 2011
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Title: CONGESTION CONTROL AND PACKET REORDERING FOR MULTIPATH TRANSMISSION CONTROL PROTOCOL
Creator: Ghose, Nirnimesh
Date: 2012-04-20, 2012-05
Description: Modern devices are equipped with multiple network interfaces. Traditionally, only one of these is in use at any given time. However,...
Show moreModern devices are equipped with multiple network interfaces. Traditionally, only one of these is in use at any given time. However, simultaneous use of these mul- tiple interfaces will lead to better user experience. Support for this multi-interface scenario has led to the development of Multipath Transmission Control Protocol or MPTCP. MPTCP, as proposed by the IETF working group mptcp, allows a single data stream to be split across multiple paths. This has obvious benefits for reliability, and it can also lead to more efficient use of network resources. But a major problem in MPTCP is the congestion control and the eventual packet reordering at the desti- nation. Various techniques for congestion control for MPTCP have been given, but the packet reordering at the destination is not considered. Efficient packet reordering schemes can drastically improve the throughput for the MPTCP protocol. Therefore, in this work various available packet reordering techniques available for single path TCP are tested in the multipath situation. These algorithms are Duplicate Selective Acknowledgement (DSACK), Eifel and Forward Retransmission Timeout (F RTO). Various network topologies are simulated in a network simulator ns-3 and measure- ments are taken for various path characteristics to see which algorithm works best for the multipath scenario.
M.S. in Electrical Engineering, May 2012
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Title: A PARAMETRIC STUDY OF THE THERMAL PERFORMANCE OF DIFFERENT WALL SYSTEMS AT VARIOUS CLIMATE ZONES
Creator: Lai, Se Yen
Date: 2013, 2013-12
Description: One of the most common energy conservative measures used is designing an air-tight and a well-insulated envelope. While there is an abundance...
Show moreOne of the most common energy conservative measures used is designing an air-tight and a well-insulated envelope. While there is an abundance of high-efficiency building envelope designs in the market which offer low thermal conductivity and high R-values as well as various studies on the thermal performance of various wall constructions, the results were often based on simplified study model and are not incompliance with the current building code. Most studies also focus on only one particular climate zone and one type of wall construction. This research aims to examine the thermal performance of different types of wall construction based on the traditional building envelope design materials in various climate zones based on insulation and air cavity placements on a non-simplified reference model that is used for construction. Study models developed are incompliance with the American Society of Heating, Refrigerating, and Air-Conditioning Engineers [ASHRAE] 90.1-2010 based on U.S. Department of Energy [DOE] Commercial Prototype Building Model. The thermal performance of the wall will be determined using two different methods. The first method will be using Building Energy Modeling [BEM] software where the exterior wall construction will be modified based on DOE reference models where the results for the overall annual energy consumption [AEC] will be compared. AEC results showed small differences between study models which are negligible. The second method is the Total Thermal Constant [TTC] method, where the thermal lag will be compared. The building structures that will be used are a steel-framed structure which represents a medium office and a wood-framed structure which represents a quick service restaurant. TTC results were able to determine the least favorable study model.
M.S. in Civil Engineering, December 2013
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Title: A UNIFIED BOUNDARY CONTROL LAW FOR DC-DC CONVERTERS USING A NORMALIZED STATE PLANE
Creator: Nie, Yue
Date: 2015, 2015-05
Description: This thesis proposes a unified boundary control law for DC-DC converters (Buck, Boost, and Buck-Boost) which improves both the transient and...
Show moreThis thesis proposes a unified boundary control law for DC-DC converters (Buck, Boost, and Buck-Boost) which improves both the transient and steady state response in comparison to boundary control laws using first or second order switching surface. A new set of switching zones on normalized state plane are defined to decide switching behavior every sample period. Additionally, non-ideal operations and a parameter self-adaptive algorithm are proposed and verified in simulation. The parameter self-adaptive algorithm enhances the system robustness and reduces the parameter sensitivity. The transient bandwidth for the load disturbance rejection and command tracking approaches the physical limits of DC-DC converters. Simulation results are presented to illustrate the major benefits of the proposed uni ed boundary control law.
M.S. in Electrical Engineering, May 2015
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Title: SUBSTATION PLANNING FOR RURAL DISTRIBUTION SYSTEMS IN AFRICAN COUNTRIES
Creator: Soyoye, Oluwadamilola
Date: 2016, 2016-12
Description: In sub-Saharan Africa, only 35% of the population is connected to grid electricity [2]. Grid-connected parts face serious transmission and...
Show moreIn sub-Saharan Africa, only 35% of the population is connected to grid electricity [2]. Grid-connected parts face serious transmission and distribution challenges. There is also the challenge of electricity demand being greater than electricity supply. These issues in all levels of the traditional power system – generation, transmission and distribution have led to gross inadequacy of electricity supply. This research focuses on the capital intensive Power Distribution Planning (PDP). Most problems in the distribution system affect the consumer directly. Distribution substation planning, a critical part of the PDP, particularly addresses the issue of overloaded distribution systems. It is not uncommon for substation transformers in some African communities to become damaged because of overloading. The choice of location, sizing, siting and number of substations is determined by considering load distribution, feeder lengths and sizes, and the interruption costs. The research illustrates a framework for substation planning, incorporating possible future load growths over a particular period to forestall unwanted failures in the distribution system. A direct algorithm is used, where the substation capacity is computed manually from the load levels at different points. This algorithm is later combined with the Mixed Integer Linear Programming (MILP) approach solved with the CPLEX solver in MATLAB.
M.S. in Electrical Engineering, December 2016
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Title: MINIMIZING SALMONELLA CONTAMINATION IN SPROUTS BY CONTROLLING THE GERMINATION TEMPERATURE
Creator: Zhang, Hanshuai
Date: 2013, 2013-12
Description: Since 1990, contaminated sprouts have been linked to at least 46 outbreaks and over 2,500 cases of illness in the US [13]. Unlike other ready...
Show moreSince 1990, contaminated sprouts have been linked to at least 46 outbreaks and over 2,500 cases of illness in the US [13]. Unlike other ready-to-eat produce, sprouts pose a particular concern as the conditions that promote germination of their seeds also facilitate the growth of pathogens [6]. To address sprout’s propensity to microbial contamination, the U.S. Food and Drug Administration (FDA) has recommended that seeds destined for sprout production be disinfected with chemical sanitizers such as 20,000 ppm of calcium hypochlorite, Ca(OCl)2 [29]. However, this disinfectant often cannot completely eliminate pathogen that may be present in seeds [4, 23]; in which case, the surviving bacteria can re-grow to significant numbers during germination and cause severe illness upon consumption [45]. Therefore, maintaining control of the germination conditions to present the proliferation of pathogens is a crucial step in the overall approach to reduce microbial hazards in finished sprouts. This study examines the effects of temperature on the proliferation of Salmonella during germination, and how this temperature effect is influenced by factors such as pathogen load, seed-lot, and the presence or absence of chemical treatment with Ca(OCl)2 was also evaluated. Alfalfa seeds artificially inoculated with ~3 log CFU/g of Salmonella were used as the contaminated seeds. They were mixed at different levels (0.01, 0.1, 1.0, or 10.0% by weight) with 200g of non-contaminated seeds and then were allowed to germinate in glass jars for 3 or 5 days at 10, 20, or 30°C. The same experiment was repeated for the spiking seeds that were treated with 20,000 ppm Ca(ClO)2 for 15 min prior to sprouting. Sprout samples were taken from each jar daily and analyzed for the level of Salmonella ix by either plating on XLD plates or the three-tube most probable number method as described in the FDA BAM. The level of Salmonella increased during sprouting at all three temperatures and reached the highest level at 48h. Sprouting at 10°C yielded the least number of Salmonella when all other factors were controlled. At all spiking levels, or the percentage of seeds contaminated before sprouting, level of Salmonella increased during sprouting, and at 20°C and 30°C, the level of Salmonella reached to a similar level of 5 log CFU/g and 7 log CFU/g respectively. At 1.0% spiking level, the level of Salmonella increased by approximately 1.5, 4.0, and 6.0 log CFU/g in sprouts grown at 10, 20, and 30°C respectively. Difference in the level of microflora background between different seed lots did not appear to affect Salmonella proliferation during sprouting. Treatments with 20,000 ppm free chlorine in some cases lowered the levels of Salmonella to undetectable levels, while in other cases, it caused an approx. 3 log reduction in Salmonella count on seeds. The surviving ones could still proliferate during sprouting although with a delay and a much slower rate, and did not reach the maximal level at 48 h of sprouting. However, Ca(OCl)2 did not prevent the re-growth of Salmonella during germination. In conclusion, these results showed that sprouting temperatures do affect Salmonella proliferations. We recommend lowering the sprouting temperature in conjunction with chemical treatment of prior to sprouting seeds to reduce microbial hazards in sprouts.
M.S. in Food Safety and Technology, December 2013
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Title: FEASIBILITY OF INDICATOR MICROORGANISMS IN ASSESSING THE EFFICACY OF SANITIZERS IN FRESH PRODUCE WASHING
Creator: Zhong, Zeyan
Date: 2016, 2016-05
Description: Sanitizers have been widely used in controlling cross-contamination during fresh produce washing processes. It is important to identify...
Show moreSanitizers have been widely used in controlling cross-contamination during fresh produce washing processes. It is important to identify different approaches for monitoring the efficacy of sanitizer washing. In this study, our objective was to determine the feasibility of indicator microorganisms in assessing the efficacy of chlorine and peroxyacetic acid (PAA) in fresh-cut produce washing. In inactivation experiments, the survivals of inoculated indicator microorganisms [total viable count (TVC), Enterobacteriaceae and total coliforms] and E. coli O157:H7 were determined after exposure to different concentrations of chlorine or PAA in water with added organic load (TOC~200 mg/l). In small-scale washing experiments, bacterial transfer from lettuce leaves inoculated with indicators or E. coli O157:H7 to wash water containing chlorine or PAA with/without organic matters was evaluated. In the inactivation study, higher log reduction was observed for Enterobacteriaceae and total coliforms than for E. coli O157:H7 after chlorine treatment at an initial concentration of 30 ppm. In the bacterial transfer study [a inoculated leaf (~5 log CFU) in 30 ml of wash water], without additional organic matter, approximately 3.5 log total CFU of all bacteria groups was transferred into wash water. Less than 1.5 log total CFU were detected for Enterobacteriaceae, total coliforms and E. coli O157:H7 in 1 ppm chlorine washing. With introduced organic matter, similar microbial loads of Enterobacteriaceae, total coliforms and E. coli O157:H7 were detected on washed leaves and in wash water with initial chlorine concentration of 1 ppm; when initial chlorine level increased to 10 ppm, less than 2 log total CFU of Enterobacteriaceae and total coliforms was detected while about 3 log total CFU of E. coli O157:H7 transferred to wash water, suggesting that chlorine at an initial concentration of 10 ppm could not prevent cross-contamination in the presence of organic load. The indicators showed different levels of survival and transfer from E. coli O157:H7 in this study and were unreliable to effectively monitor the behavior of the pathogen during chlorine wash in fresh produce processes. Enterobacteriaceae and total coliforms were more vulnerable to 40 ppm PAA treatment than E. coli O157:H7 in PAA inactivation experiments. No survival, except for TVC, was observed after 80 ppm of PAA inactivation. In the bacterial transfer study, 40 ppm PAA in wash water was found unable to prevent cross-contamination of indicators and E. coli O157:H7 from leaves to water. Further investigation is needed to compare the bacterial transfer levels of E. coli O157:H7 and the indicators at higher PAA levels.
M.S. in Food Safety and Technology, May 2016
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Title: APPLICABILITY OF THE INTERVAL ANALYSIS METHOD TO RELIABILITY ASSESSMENT OF STRUCTURES
Creator: Taha, Raguez A.
Date: 2012-11-26, 2012-12
Description: The scope of this study is focused on the applicability of the interval method to the reliability analysis of structures. The study includes...
Show moreThe scope of this study is focused on the applicability of the interval method to the reliability analysis of structures. The study includes using the traditional probability methods in several applications and comparing the results with the interval analysis. Accordingly, the interval arithmetic rules are applied in several examples and the results are compared with those from the traditional probability theory concepts. Specifically, the procedure for using the interval methods was applied to the development of the probability of failure for a simple structural member; and for a link in a network system. Through three simple examples, the research shows that the interval method offers comparable results with those from the traditional first-order reliability method. The procedure based on the interval method, however, may offer advantages, especially in cases where the uncertainties in various parameters describing the reliability of a system are large. In the presence of large uncertainties, the traditional methods of reliability analysis, based on the first order approximation, may lose their accuracy. In these cases, the interval method may offer a simple method yet with more accurate results.
M.S. in Civil Engineering, December 2012
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Title: STUDY OF VITREOSCILLA HEMOGLOBIN VARIANTS PRODUCED BY RANDOM MUTAGENESIS
Creator: Lin, Xiaodan
Date: 2015, 2015-05
Description: This study is focused on comparing the wild type and mutated versions of the Vitreoscilla hemoglobin gene (vgb). The purpose of this focus is...
Show moreThis study is focused on comparing the wild type and mutated versions of the Vitreoscilla hemoglobin gene (vgb). The purpose of this focus is to find out whether any of the vgb mutations provides an advantage regarding cell growth rate, as well as on the expression level of Vitreoscilla hemoglobin protein (VHb). A negative control Escherichia coli DH5α (E. coli DH5α) bearing no pUC plasmid, as well as seven E. coli DH5α strains bearing different pUC-based plasmids were tested in the experiments. Among these were one vector-only negative control (pUC18), one wild type positive control (pUC8:16, which carries wild type vgb) and five different types of pUC-bearing vgb mutants (pUC-vgb M1, M2, M3, M4 and pUC18-vgb M3). In order to compare cell growth rate among these strains, the growth rate assay was carried out under three different conditions: (1) Luria-Bertani (LB) medium, aerobic conditions; (2) Terrific Broth (TB) medium, low oxygen conditions; and (3) TB medium, microaerobic conditions. In addition, the carbon monoxide (CO) difference spectra assay was conducted to measure functioning VHb protein expression levels for the strains grown under aerobic conditions. In contrast to the results obtained by our Australian collaborators, our growth rate assay and CO difference spectra assay showed no growth advantage or higher expression level of functioning VHb protein due to any of the vgb mutations. For the further study of the vgb mutants, four different recombinant plasmids were constructed by cloning three types of mutated vgb (vgb M1, M3 and M4) as well as wild type vgb into the prokaryotic expression vector pUC8 with ampicillin (Amp) resistance. After being transformed into competent E. coli DH5α cell, these resulting xii strains, as well as the plasmid-free negative control (E. coli DH5α) and vector-only negative control (E. coli DH5α bearing plasmid pUC8) were tested by the CO difference spectra assay. Except strain E. coli DH5α [pUC8-vgb M3], which showed a slight increase in the VHb expression level, the strain bearing other mutated vgbs did not demonstrate any elevation in VHb protein expression level, compared to the positive control containing wild type vgb.
M.S. in Biology, May 2015
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Title: FUNCTIONAL ANALYSIS OF POTENTIAL PHOSPHORYLATION SITES IN BAXΔ2 UNIQUE OLIGOPEPTIDE
Creator: Tsai, Yu-tseng
Date: 2014, 2014-07
Description: The tumor suppressor gene, Bax, plays a critical role in tumor progression through regulating cell apoptosis. Mutations on the BAX gene often...
Show moreThe tumor suppressor gene, Bax, plays a critical role in tumor progression through regulating cell apoptosis. Mutations on the BAX gene often result in silencing its expression and the loss of pro-death ability. However, there is a unique Bax isoform, BaxΔ2, recently discovered in these Bax mutated cancer cells. BaxΔ2 isoform shows higher pro-apoptotic activity than Baxα. Unlike the parental Baxα, BaxΔ2 does not target mitochondria and forms aggregates in cytosol. There is a unique 10-amino-acid peptide in the N-terminus of BaxΔ2 protein possible function as a special signal. Two serines in this region are predicted as potential phosphorylation sites for regulation of the protein activity. To test this hypothesis, we mutated both serines (SS) into non-phosphorylatable alanines (AA) by site-directed mutagenesis approach. Both BaxΔ2 wild type (BaxΔ2-SS) and mutants (BaxΔ2-AA) were tagged with GFP, which allows us to monitor the protein expression and cellular localization in live cells. Here, we found that the distribution patterns of BaxΔ2-AA and BaxΔ2-SS were similar and appeared as aggregates in cytosol. BaxΔ2-AA mutant also possessed the similar pro-apoptotic activity with BaxΔ2-SS wild type. These results suggested that the two serines in BaxΔ2 unique oligopeptide might not play a critical role in BaxΔ2 localization and pro-death activity under the current ectopic expression conditions. Further study is needed to have better understanding of phosphorylation in contribution to unique behavior of BaxΔ2.
M.S. in Biology, July 2014
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Title: The utilization of sunflower stalks in paper manufacture
Creator: Zavertnik, J.
Date: 2009, 1914
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/utilizationofsun00zave
Thesis (B.S.)--Armour Institute of Technology

Title: POINT CLOUD FUSION BETWEEEN AERIAL AND VEHICLE LIDAR
Creator: Guangyao, Ma
Date: 2015, 2015-05
Description: Because of the increasing requirement of precision in region of 3-D map, we began to use LiDAR to establish a more accurate map. There still...
Show moreBecause of the increasing requirement of precision in region of 3-D map, we began to use LiDAR to establish a more accurate map. There still exist some problems although we have already made a great progress in this area. One of them, which I tried to process during my thesis study, is that we have two points source - Aerial LiDAR Data( Points gotten by Airplane ) and Vehicle LiDAR Data( Points gotten by Vehicle ) - while both of them have a different density and cannot be merged well. This process - Fusion-is kindly similar to registration, the difference is that the points we would like to merge are generated from different devices and have only few points pairs in the same region. For example, the Aerial LiDAR data has a higher points density in the roofs and ground, but lower in the walls. In the meanwhile, the Vehicle LiDAR data has a lot of points in the walls and ground region. It is beneficial to minimize the difference between these two point sets since the process is necessary for modeling, registration and so on. Therefore, my thesis is to minimize the difference between these two data sources, a procedure of Fusion. The main idea is to read the LiDAR data into data structure of Point Cloud, sample their density to the similar level, and select several corresponding special region pairs( we named these regions -chunks, e.g. Median strip and boundaries of road ) with sufficient interesting points to do fusion. Interesting points indicate the points with one and more special features among all points. And, the algorithm we used to implement the fusion is ICP( Iterative Closet Point Algorithm). Not similar to Registration of Point Cloud, research in the Fusion area is rare. Therefore, the existing algorithms are not well suitable in this project. I deduce some new algorithms during my research since the original ICP Algorithm cannot work well. Both Update Equation and Objective Function are modified. In this thesis, PCL( Point Cloud Library ) is mainly used to implement the basic function, such as nding the nearest points and sampling point cloud, and Eigen library to write the core functions( e.g. Modified Iterative Closest Point Alg ). I also use libLAS library to implement the IO operations and MeshLab to visualize the point cloud after modification.
M.S. in Computer Science, May 2015
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Title: INVESTIGATION OF NOROVIRUS CROSS CONTAMINATION DURING FOOD SERVICE PROCEDURES USED IN PREPARATION OF FRESH PRODUCE
Creator: Suriyanarayanan, Annamalai
Date: 2011-11, 2011-12
Description: Human norovirus (HuNoV) is considered an important cause of foodborne outbreaks, often attributed to the preparation of fresh produce by...
Show moreHuman norovirus (HuNoV) is considered an important cause of foodborne outbreaks, often attributed to the preparation of fresh produce by infected food handlers. In this investigation, methods for recovery of murine norovirus (MNV-1), a surrogate for HuNoV, from food preparatory surfaces were optimized, and MNV-1 crosscontamination between various surfaces common in a food service setting were studied. Fifty microliters of MNV-1 was inoculated onto demarcated 1 x 1 inch squares of polypropylene cutting board, stainless steel knife and spigots. After drying, MNV-1 was recovered from each surface using either a cotton swab, composite tissue or sterile sponge in combination with different eluents such as tissue culture growth medium, 3% beef extract, glycine buffer (50mM glycine, 1% beef extract), stripping solution (0.04% K2HPO4, 1.01% Na2HPO4, 0.1% Triton X-100), and Earle’s Balanced Salt Solution (EBSS). The eluent/recovery tool combinations that recovered the highest percentage of MNV-1 from cutting board were stripping solution/sponge (20%) and growth medium/swab (20%). The greatest recovery from the knife blade was achieved with the growth medium/composite tissue combination (43%), while recovery from spigots was greatest using the stripping solution/sponge (28%) and the growth medium/sponge combinations (27%). In the second phase of this investigation, human volunteers were asked to perform various tasks in order to quantify the amount of MNV-1 cross contamination between various surfaces, including bare hands, fresh-cut lettuce, and spigots. The percentage of MNV-1 transfer from hands to spigots varied from 0.06% to 3.59%, spigots to hands varied from 10% to 90.4% and lettuce to hands varied from 0.30% to 4.33%. x The results of this investigation can be used in developing a model describing the transfer pattern of HuNoV between surfaces common in retail food service, and used in developing educational materials for food service workers.
M.S. in Science, Food Safety, and Technology, December 2011
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Title: PULSED LIGHT INACTIVATION OF MURINE NOROVIRUS ON VARIOUS FOOD CONTACT SURFACES
Creator: Zhou, Zijin
Date: 2015, 2015-07
Description: Norovirus is one of the leading causes for foodborne illness. Transmission of virus from surface to food has been known to cause a number of...
Show moreNorovirus is one of the leading causes for foodborne illness. Transmission of virus from surface to food has been known to cause a number of outbreaks. Studies of norovirus have been conducted using Murine Norovirus to simulate the behaviors. Pulsed light (PL) is a promising surface decontamination technology, which has the potential to be applied in a food service setting. PL uses intense pulses of short duration and a broad spectrum to accomplish microbial inactivation. This study evaluates the effect of PL on MNV-1, artificially inoculated onto various food contact surfaces including 304 stainless steel, glazed tile, polypropylene, and ultra-high molecular weight (UHMW) polyethylene. The virus was allowed to inoculate on the coupons for 20mins and treated with PL in a Xenon Steripulse XL-3000TM pulsed light treatment system for up to 60 s, at a distance of 8.3 cm 10.8 cm or 13.3cm from the central axis of the lamp. An infrared (IR) camera was used to record surface temperatures, in 1-s increments. After PL treatments, remaining viruses were recovered from surfaces and quantified by plaque assay. At a distance of 10.8cm, MNV-1 was reduced by 2.22-, 2.27- 2.75- and 3.12-log, after 20s treatment on inoculated stainless steel, glazed tile, UHMW polyethylene and polypropylene, respectively. After 50s treatment, MNV-1 was reduced by 4.86- and 5.93- log on glazed tile and stainless steel surface respectively. The surface temperature on tile and stainless steel increased at the rate of 1.08±0.20 and 1.28±0.32°C /s respectively. A relatively short treatment using pulsed light is sufficient to inactivate MNV-1 on the surface of materials commonly used in food preparation. The results suggest that the technology has the potential to reduce surface viral contamination in a food preparation setting.
M.S. in Food Safety and Technology, July 2015
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Title: STUDY OF SALMONELLA SURVIVAL ON THE SURFACE OF FRUITS
Creator: Sui, Ke
Date: 2017, 2017-05
Description: Salmonella enterica has been frequently linked to the major foodborne disease outbreaks. The molecular mechanisms underlying this pathogen...
Show moreSalmonella enterica has been frequently linked to the major foodborne disease outbreaks. The molecular mechanisms underlying this pathogen survival on the fresh fruit surface remain largely unexplored. In this study, the environmental factors that affect the survival of Salmonella strains on the surface of selected fruits were studied. Grape tomatoes (or cantaloupe peels) were inoculated in three separate trials with 1 mL Salmonella enterica serotypes Enteritidis or Typhimurium (approximately 1010-11 CFU/mL). Storage of grape tomatoes at 4 ℃ resulted in significant decrease in populations of S. Enteritidis; this trend was observed at both of the tested relative humidity with the D-value as 7.25±1.05 d and 7.28±2.34 d, respectively. At different temperatures, relative humidity only had marginal effects on the bacterial survival on the surface of grape tomato and cantaloupe. In addition, S. Typhimurium apparently survived better than S. Enteritidis on the surface of grape tomato. Furthermore, a transposonmutagenesis library with random transposon insertion mutants of S. Enteritidis and high-throughput sequencing analysis showed that the expression of genes rcsB and nlpD were hypothesized to be associated with the survival of S. Enteritidis on grape tomatoes. Inframe deletions of the two genes in S. Enteritidis were constructed by lambda red recombinase system and respective complementation mutants were also obtained for identification of the contribution of the two genes to the bacterial survival on the surface of grape tomato. Thus, this study provided microbiological and molecular microbiological basis to probe the roles of putative genes in Salmonella enterica survival on the surface of fresh fruits.
M.S. in Food Safety and Technology, May 2017
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Title: LENGTH DEPENDENT ACTIVATION IN MANDUCA SEXTA FLIGHT MUSCLE
Creator: Kumar, Mohit
Date: 2011-08-09, 2011-07
Description: The flight muscle of Manduca sexta has some interesting properties. It is synchronous, like mammalian skeletal and cardiac striated muscle,...
Show moreThe flight muscle of Manduca sexta has some interesting properties. It is synchronous, like mammalian skeletal and cardiac striated muscle, but it is structurally similar to the more widely studied asynchronous insect flight muscles of Drosophila and Lethocerus. One of the main goals of the thesis is to generate a useful skinned preparation for mechanical studies in vitro. A number of different skinning protocols were tried and evaluated for preservation of structural integrity by using light and X-ray diffraction. In all muscles studied to date, isometric force is a function of the [Ca2+] of the bathing solution and also a function of the sarcomere length whereby more force is generated at a longer sarcomere length than at a shorter for the same [Ca2+]. This phenomenon is termed “length dependent activation” (LDA). To date no real studies on the force-pCa relationship has been done on Manduca sexta flight muscle. This force-pCa analysis would give us some insight into the length dependent activation (LDA) in this novel insect flight muscle system. The present studies were undertaken to characterize and analyze the force-pCa relationships in Manduca sexta. Conditions were found that allowed skinning muscles while maintaining good structural order. We found that both DLMs dorsal and ventral show length-dependent activation at longer SL. Our study also shows that ventral muscles are more cooperative than the dorsal muscles which may be related to their different functions in vivo.
M.S. in Biological, Chemical, and Physical Sciences, July 2011
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