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- Title
- DYNAMIC SIMULATION AND LOAD MODELING FOR VOLTAGE RECOVERY STUDIES WITH THREE-PHASE AND SINGLE-PHASE INDUCTION MOTORS
- Creator
- Zhang, Jingpei
- Date
- 2017, 2017-05
- Description
-
Transient stability topics have been popular in modern power systems and time domain simulation provides an efficient evaluation for...
Show moreTransient stability topics have been popular in modern power systems and time domain simulation provides an efficient evaluation for correlative studies. So far, we have been working on developing advanced time-domain simulator TS3ph, which implements simulation on electromechanical level but with three-phase completed network model to enable unbalanced modeling and simulation. In this paper, modeling and development work of TS3ph are being introduced. Positive-sequence equivalent and three-phase based models, including static var compensator, governor and three-phase induction motor models, are built and validated to evaluate their dynamic behaviors in transient state. Moreover, research work on single phase induction motor model development, including important motor behaviors such as motor stalling, is also introduced in this paper for voltage collapse and recovery study. This is indeed the first time to apply such model on electromechanical simulator as well.
M.S. in Electrical Engineering, May 2017
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- Title
- TEMPERATURE PROFILES THROUGH THE SHELL IN EGGS HEATED BY INFRARED ENERGY
- Creator
- Guo, Jingxin
- Date
- 2012-07-30, 2012-07
- Description
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Infrared heating is an effective method for surface pasteurization of shell eggs. As the external temperature reaches the inactivation...
Show moreInfrared heating is an effective method for surface pasteurization of shell eggs. As the external temperature reaches the inactivation temperature, internal temperatures could become great enough to denature albumen. However, the internal temperature of albumen at the shell cannot be measured directly. The purpose of this study is to use experimental data to understand the response of the albumen temperature at the shell to infrared radiation impinging at its outer surface. Fresh eggs were obtained from a local producer and refrigerated until needed. They were prepared for each experiment by overnight equilibration with ambient conditions. Each egg was placed on a metal stage over which an infrared lamp was positioned. The stage allowed a K-type thermocouple to be inserted through a small hole in the shell opposite of the shell area facing the lamp. The thermocouple was pushed into the egg such that the tip was against the inner surface of the shell just underneath the exposed area. The external temperature of this area was measured by an infrared pyrometer. Variables for these experiments were temperature of the IR lamp (277°C, 329°C, 391°C and 452°C), distance between shell egg and IR lamp (3.13 cm – 15.83 cm), and treatment time. All experiments share the same initial lag around 30s, suggested that the initial lag did not vary with changing of lamp-egg distances and lamp temperatures. After the initial lag, internal and external temperatures were found to increase at the same rate regardless of experimental parameters, indicating and equilibrium between the infrared energy impinging on the surface and its dissipation in the interior of the egg. The difference of temperature distributes between 10°C to 20°C. However, lowering lamp temperatures or increasing distances did not change this difference significantly. Moreover, the temperature gap sustains the same temperature after initial lag. The results showed that the internal temperature could be inferred via measuring external temperature. This is valuable in processing to maximize external surface temperature while protecting heat sensitive albumen. Future work will involve modeling the heating phenomenon to determine if knowing only the lamp temperature and distance is sufficient for predicting internal temperature.
M.S. in Food Processing Engineering, July 2012
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- Title
- Learning Company, Literacy Center, Johannesburg, South Africa
- Creator
- Gray, Aisling
- Date
- 2010-07-29
- Title
- BICYCLE CRASH ANALYSIS IN CHICAGO
- Creator
- Van Nortwick, Taylor Wade
- Date
- 2013, 2013-07
- Description
-
The United States is making big plans for improvements in bicycle infrastructure. To best understand if the improvements will be successful in...
Show moreThe United States is making big plans for improvements in bicycle infrastructure. To best understand if the improvements will be successful in creating a safe network, a study was done to determine contributing factors in bicycle crashes. Bicycle and motor vehicle crash data from around Chicago between 2005 and 2011 was analyzed for significant factors in infrastructure, cyclist and motorist attributes. Temperature was used as a predictor of bicycle traffic due to the seasonality of bicycling in Chicago. It was found that more bicycles and vehicles result in higher crash rates. It was also found that on -street parallel parking, signalized, skewed and multiple legged intersections lead to higher crash rates.
M.S. in Civil Engineering, July 2013
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- Title
- DEVELOPMENT AND APPLICATION OF THE KIRIE WASTEWATER TREATMENT PLANT MODEL
- Creator
- Mendez, Thomas E.
- Date
- 2012-07-15, 2012-07
- Description
-
The Metropolitan Water Reclamation District of Greater Chicago (MWRDGC) is tasked with protecting the public’s water supply and improving the...
Show moreThe Metropolitan Water Reclamation District of Greater Chicago (MWRDGC) is tasked with protecting the public’s water supply and improving the quality of water in their service area’s watercourses. Principal in this mission are the seven wastewater treatment plants that are operated by MWRDGC. The greater Chicago area possesses a combined sewer system (CSS) that combines sanitary sewage and stormwater runoff. Because of this CSS, water reclamation plants are burdened with not only processing sewage and sanitary waste, but also stormwater runoff. As a result there can be a large variation in water quality and quantity. MWRDGC’s newest water reclamation plant is the James C. Kirie Water Reclamation Plant, which was completed in 1980. This plant operates as a nitrification plant with no separate distinct denitrification process. It is important to note that no clearly defined unit processes such as nitrification towers are utilized at the Kirie Water Reclamation Plant. Nitrification occurs primarily in the aeration basins and is currently sufficient to meet water quality standards. However, because of the current regulatory climate, stricter standards on effluent discharge are likely in the near future especially with respect to nutrients. Stricter standards on total nitrogen in effluent instead of the current ammonia limits are one such expected water quality change. As a result of this expectation, modeling modifications and processes at a treatment plant can be a key tool in adjusting to evolving standards. Because water reclamation plants vary greatly depending on their technology, influent and processes, computer modeling provides a convenient way to assess how the plant will react to dynamic changes in influent quality and still be able to meet static effluent standards. Although computer modeling has been applied to water reclamation plants for some time now, there are no clearly defined or accepted protocols for this modeling. Combined with the variation exhibited by various types of water reclamation plants, often modeling protocols must be custom created for individual plants or types of plants. What follows is a study and simulation of the Kirie Water Reclamation Plant. Simulation was used to examine wet weather events at the Kirie Water Reclamation Plant. Wet weather phenomena were explored in step-wise manner to determine the relative effects of different perturbations in influent water quality and quantity. The results show the various effects in effluent quality depending upon the variable or combination of variables deviated. Deviations in temperature and flow dominate all other variations simulated and result in the largest effect on effluent water quality. Deviations of 50% to both temperature and flow simultaneously yielded an increase in effluent BOD and NH3 at twice and six times the steady state values, respectively.
M.S. in Environmental Engineering, July 2012
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- Title
- SYSTEM-ON-CHIP ARCHITECTURES FOR SIGNAL PROCESSING AND COMMUNICAnONS
- Creator
- Niu, Sufeng
- Date
- 2012-04-30, 2012-05
- Description
-
System-On-Chip (SOC) is one of the most popular Computer Aided Design (CAD) methodologies in electronic system design. In this research, SOC...
Show moreSystem-On-Chip (SOC) is one of the most popular Computer Aided Design (CAD) methodologies in electronic system design. In this research, SOC design is investigated in two different types of applications: i) low cost and power efficient applications; and ii) high performance computing applications. To explore low cost and power efficient design, a microcontroller based wireless medical system is investigated. Two wireless communication protocols for medical applications and patient monitoring are analyzed. In addition, the ZigBee stack developed by TI and a medical amplifier are discussed. For high performance SOC applications, implementations of several matrix operations are examined. An improved fixed-point hardware design of QR decomposition is introduced and optimized for Xilinx FPGAs. A Givens Rotation algorithm is implemented using a folded systolic array and the CORDIC algorithm. This approach is highly suitable for high-speed FPGAs or ASIC designs. It is found that the Xilinx XC5VLX110T FPGA is capable of running the QR decomposition at 246MHz.
M.S. in Electrical Engineering, May 2012
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- Title
- OPTIMAL BIDDING STRATEGY FOR HYDRO UNIT
- Creator
- Zhu, Renchen
- Date
- 2013-04-30, 2013-05
- Description
-
The bidding price for the renewable energy is very different from some traditional energy, like gas, coal and so on, because when we produced...
Show moreThe bidding price for the renewable energy is very different from some traditional energy, like gas, coal and so on, because when we produced the renewable energy, the only cost is the generator unit cost, for example, wind power, water power and so on. People never need to pay the fuel price for the solar, water or wind. So here come one question how can we decide the energy price for these power. As we all know, the bidding price decided the profit for the generating company. Nowadays, more and more researches have been done in this field for every company want a good price to earn the highest profit. But for the renewable energy, they are different from the traditional energy which price is determined by the fuel price. So how to decide the bidding price of the renewable energy will be a good topic and question for us. To solve this problem, I will try to use an idea called minimum the imbalance in order to maximum the profit for those owners. This idea first has been applied in the wind unit. For my thesis, I will apply this idea to the hydro unit both with the storage and without storage. For each part, I will use some data to test. By these testing, the result will show this bidding strategy will be better.
M.S. in Electrical Engineering, May 2013
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- Title
- THERMODYNAMICS AND PHASE EQUILIBRIA OF HEUSLER ALLOYS
- Creator
- Chung, Yoonsung
- Date
- 2011-09, 2011-07
- Description
-
Heusler compounds are of great interest for their properties such as shape memory, thermoelectric, ferromagnetic and spin polarization effects...
Show moreHeusler compounds are of great interest for their properties such as shape memory, thermoelectric, ferromagnetic and spin polarization effects that could lead to new mechanical and electronic devices. Currently, the study of Heusler alloys is focused on their electronic and magnetic properties, but the high temperature thermodynamic properties of these compounds have not been covered as much. A thorough knowledge of the thermodynamic properties and phase equilibria is required for developing this kind of alloys. This thesis is part of a systematic investigation of the thermodynamics and phase equilibria of ternary Heusler alloy systems. In this work, the high temperature reaction calorimeter was used to obtain the standard enthalpy of formation of compounds in the Ni2XSn (X = Ti, Zr, Hf, V and Nb) and Ni2TiX (X = Ga and In) ternary systems. It was confirmed the compound Ni2TaSn does not exist in the Heusler structure A Setaram Ligne 96 drop calorimeter was used to measure the heat content of Ni2TiSn as a function of temperature. Phase equilibria and crystal structures of Ni2TiSn, Ni2TiGa and Ni2TiIn were determined using XRD, SEM and EDS.
M.S. in Materials Science & Engineering, July 2011
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- Title
- ISOLATION OF MONOSPECIFIC ANTIBODY AGAINST SPLICED VARIANT OF DYSTROPHIN PROTEIN USING YEAST SURFACE DISPLAY TECHNIQUE
- Creator
- Saraswathi, Raj Prabu Vijayakumar
- Date
- 2011-05-04, 2011-05
- Description
-
Dystrophin gene is the largest in the human genome with 79 exons covering greater than 0.1% of the total genome, located on the Xp21 locus of...
Show moreDystrophin gene is the largest in the human genome with 79 exons covering greater than 0.1% of the total genome, located on the Xp21 locus of the “X” chromosome resulting in a 427kDa protein, “Dystrophin”. Dystrophin is an important cytoskeletal protein which belongs to the β-Spectrin/α-actinin family of proteins. It comprises of an amino terminal domain, alpha helical coiled structure COOH domain, central rod region with 24 STRs and four proline rich hinge regions. It plays a vital role in localizing the Dystrophin glycoprotein complex (DGC) in the Sarcollema and is associated with the DGC in controlling the signaling events of certain proteins associated with DGC. The large size of the gene makes it more vulnerable to mutations resulting in partially functional or non-functional Dystrophin. The absence of Dystrophin results in disruption of sub sarcolemma-extracellular matrix linkage, loss of nitric oxide, progressive muscle weakening and muscle wasting leading to the death of patients typically before the end of their teenage. In certain cases alternatively spliced isoforms produce Dystrophin with reduced length yet stable and completely functionality. The main focus of this project was to select monospecific antibody against the more stable alternatively spliced variant D14 (15”16”) 17, which is functional and more stable compared to unspliced parent D14:17. The yeast surface display technique was used to effectively screen and select the yeast scFv clones containing the monospecific antibody against our target spliced variant D14 (15”16”) 17 protein and D2:3. The yeast scFv sub population was enriched by repeated MACS and FACS selection. Test colonies picked from the enriched scFv pool were confirmed via PCR and restriction digestion analysis. The scFv for the respective antigens were then sub cloned into pPnnl-9 secretion vector using YVH10 yeast cells via LiTRAFCO method. It was clear that by repeated MACS and FACS selection the scFv pool can be enriched and the yeast scFv clone sub population can be reduced to a significant level. The scFv sub cloned into Pnnl-9 secretion vector can be purified using affinity chromatography and the further affinity and avidity studies can be conducted.
M.S. in Biology, May 2011
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- Title
- L2E ESTIMATOR FOR THE CATEGORICAL MODEL WITH ELASTIC NET PENALTY
- Creator
- Wang, Yuan
- Date
- 2017, 2017-07
- Description
-
The logistic regression model is an important generalized linear model for the categorical data. The maximum likelihood estimation is mostly...
Show moreThe logistic regression model is an important generalized linear model for the categorical data. The maximum likelihood estimation is mostly used in estimating the parameters of the logistic regression model. However, the maximum likelihood estimation is very sensitive to outliers which will cause the inaccuracies of the fitted parameters and model selection in high-dimensional regression. Chi and Scott (2014) demonstrated by simulation that minimizing the integrated square error or L2 estimation (L2E) is a robust method to fit 2-class categorical models. They also showed that the L2E estimation method can select the right model even in the presence of many outliers in high dimensional scenarios. In my thesis, I extended the L2E estimation method from 2-class to 3-class based on the MM algorithm by Chi and Scott (2014). Then I demonstrated the properties above for 2-class categorical models are also applicable to 3-class ones.
M.S. in Applied Mathematics, July 2017
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- Title
- PARAMETRIC IMAGE ESTIMATION IN ANALYZER-BASED PHASE CONTRAST IMAGING
- Creator
- Caudevilla, Oriol
- Date
- 2014, 2014-07
- Description
-
Since the discovery of X-rays, by W.E. Roentgen in 1895, absorption-contrast imaging has been widely used in medical diagnostic, for example:...
Show moreSince the discovery of X-rays, by W.E. Roentgen in 1895, absorption-contrast imaging has been widely used in medical diagnostic, for example: mammography, chest X-ray, angiography etc. Over the last 25 years many researchers have shown that phase-contrast X-ray imaging is capable of obtaining a better contrast then classical absorption-contrast imaging. This is especially true in soft tissue imaging like mammography or at higher Xrays energies. During the past five years a significant effort has made in development of a tabletop analyzer-based phase-contrast system. In this system a perfect crystal is used to generate a quasi-monochromatic beam, which after interacting with an object is analyzed by a second perfect crystal called analyzer. The need of quasi-monochromatic beam and the low brilliance of conventional X-ray sources (CXS) has been the major limiting factor for tabletop systems. The work presents in this thesis aims to develop novel reconstruction methods for tabletop analyzer-based phase-contrast imaging (ABI) systems. The presented reconstruction methods goal is to minimize the impact of CXS low brilliance by utilizing phase-contrast image formation model and maximum or maximum-a-posteriori Poisson likelihood approach. Finally, a fast-convergent conjugate gradient optimization algorithm has been derived specifically for Poisson likelihood function maximization.
M.S. in Electrical Engineering, July 2014
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- Title
- An Alternative Car Show: An Alternateive Vehicle Insfrastructure
- Creator
- Hopkins, Kyle
- Date
- 2010-07-29
- Title
- Thermal conductivity
- Creator
- Bauer, W. Ernest, Jr
- Date
- 2009, 1917
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/thermalconductiv00baue
Thesis (B.S.)--Armour Institute of Technology; Includes folded leaves in back pocket
- Title
- POWER ANALYSIS AND CONTROL OPTIMIZATION OF A HIGH GAIN RESONANT DC-DC CONVERTER
- Creator
- Wu, Haowen
- Date
- 2017, 2017-05
- Description
-
Applications of DC-DC converter require a high power, high efficiency performance, especially for automotive applications and renewable energy...
Show moreApplications of DC-DC converter require a high power, high efficiency performance, especially for automotive applications and renewable energy applications. A desired converter should have a fast response, stable output in different conditions. This thesis studies a novel high gain DC-DC resonant converter and its control. Based on the circuit analysis and operation evaluation, feed-forward and feedback control methods are proposed in order to achieve stability under variety of changes. Moreover, circuit topology is investigated in response to the efficiency improvement. Simulations in PSIM, PLECS and MATLAB Simulink have been carried out to validate the controller design and topology development. The simulation results are in consistence to the theoretical analysis. The overall high efficiency at nominal operating point is further increased.
M.S. in Electrical Engineering, May 2017
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- Title
- A system of multiplex telephony by the use of vacuum tubes
- Creator
- Arnold, E. H., Throop, A. R.
- Date
- 2009, 1919
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/systemofmultiple00arno
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 44-45
- Title
- RECEIVER AUTONOMOUS INTEGRITY MONITORING AGAINST ORBIT EPHEMERIS FAULTS IN CARRIER PHASE DIFFERENTIAL GPS
- Creator
- Stevanovic, Stefan
- Date
- 2013-04-18, 2013-05
- Description
-
This work investigates the potential of the Global Positioning System (GPS) to enable a safe approach for rendezvous applications including...
Show moreThis work investigates the potential of the Global Positioning System (GPS) to enable a safe approach for rendezvous applications including shipboard landing of military aircraft. GPS has been shown to have the necessary accuracy for such an operation, and could potentially replace the existing radar or laser based systems. [Kha08][WPF08]1 However, to ensure safe operation, GPS must also be able to avoid hazardous situations. Shipboard aircraft approach navigation is an example rendezvous application requiring both high accuracy and high integrity. In this work, GPS measurement error models and orbit ephemeris fault (OEF) detection algorithms are developed for rendezvous applications, and performance is analyzed for the aircraft shipboard landing application. Both reference station and user based monitors can be used for orbit ephemeris fault detection. The available reference monitors either require a stationary reference receiver, or cannot protect against all types of orbit ephemeris faults. As an alternative, this work develops and investigates the use of receiver autonomous integrity monitoring (RAIM), which is user-based. Two contrasting algorithms, differential RAIM (DRAIM) and relative RAIM (RRAIM) are derived and analyzed for a realistic shipboard landing application. DRAIM is most effective when the aircraft first begins the approach. On the other hand, RRAIM performs best near the end of the approach. Assessing integrity risk is shown to be a major challenge for the RRAIM algorithm. Thus, a new unified RAIM (URAIM) concept is introduced. It seamlessly integrates DRAIM and RRAIM into a single detection algorithm, and also facilitates integrity risk evaluation. This is because the URAIM measurement equation can be used for both position estimation as well as fault detection. 1Corresponding to references in the Bibliography. xii Since high accuracy is desired, fixing integer cycle ambiguities is required. The Enforced Position-Domain Integrity-Risk Cycle Resolution Algorithm (EPIC) method of integrity risk bounding is used along with the URAIM fault detection algorithm in what we call the EPIC-URAIM algorithm. In general, the OEF will interfere with the cycle resolution process. In this work, the EPIC integrity risk bound formula is modified to account for the presence of an OEF. The EPIC-URAIM algorithm is simulated for 1507 sea-based locations around the globe. An average global availability of accuracy and integrity of 98.6% is achieved. This work illustrates the feasibility of detecting orbit ephemeris faults with integrity, while simultaneously meeting stringent accuracy requirements for real-time rendezvous navigation applications.
M.S. in Mechanical and Aerospace Engineering, May 2013
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- Title
- FABRICATION, CHARACTERIZATION AND RELEASE STUDIES OF LOW DENSITY POLYETHYLENE/CLAY NANOCOMPOSITES
- Creator
- Zhao, Ziqian
- Date
- 2015, 2015-07
- Description
-
Nanocomposites exhibit enhanced physical properties including mechanical strength, thermal stability, and gas barrier properties. The...
Show moreNanocomposites exhibit enhanced physical properties including mechanical strength, thermal stability, and gas barrier properties. The development of nanocomposites has led to applications in food industry, mostly in food packaging. The application of nanocomposites in food packaging may extend the shelf life of a food, thus increasing the market value for manufactures. However, there is limited data and research to assess the risk of exposure of nanomaterials to consumers. This project aims at evaluating the factors that can influence the release of nanomateirals in low density polyethylene/clay nanocomposites films. Nanocomposites based on low density polyethylene (LDPE), containing 1, 3, 5 and 7 wt.% of Cloisite 20A and maleic anhydride-grafted polyethylene (MAPE) as a compatibilizer were prepared by melt compounding and characterized in this thesis project. Cloisite 20A is mostly composed of montmorillonite (MMT), which is commonly used as a nanoscale size filler. LDPE/Clay nanocomposite films containing MMT and three mass equivalents of MAPE were successfully extruded into thin films with good optical clarity. The materials were characterized by using transmission electron microscope (TEM), thermogravimetric analysis (TGA), oxygen permeation analysis and a material testing machine. Important properties such as tensile modulus, oxygen transmission rate, thermal resistance and glass transition temperature were measured. Nanocomposite films were immersed in three kinds of food simulants (absolute ethanol, 3% acetic acid and deionized water). Storage time, storage temperature and percent fill of clay were evaluated as the factors that can influence the release of nanomaterials. The content of released of Al, Mg, and Si was quantified using inductively coupled plasma mass spectrometry (ICP-MS). Mg, Al and Si were continuously released from nanocomposite films in duration of 30 days. Fastest releasing speed was found in 3% aqueous acid at 75 °C, and lower temperature can largely decrease the release of nanoparticles. This project is an initial attempt to assess the risks from the use of nanocomposites as food packaging.
M.S. in Food Safety and Technology, July 2015
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- Title
- SURVIVAL OF SALMONELLA ON CHAMOMILE, PEPPERMINT AND GREEN TEA DURING STORAGE RELATED TO TEMPERATURE AND HUMIDITY
- Creator
- Chen, Zhengzai
- Date
- 2013-04-24, 2013-05
- Description
-
Botanical/herbal teas may contain antimicrobial compounds that will affect the survival and persistence of the native as well as contaminant...
Show moreBotanical/herbal teas may contain antimicrobial compounds that will affect the survival and persistence of the native as well as contaminant microflora. Although Salmonella are known for their ability to survive in low water activity environments, their survival on dry botanical/herbal teas has not been examined. The purpose of this work is to determine the survival of Salmonella on three types of teas, chamomile peppermint, and green tea under different storage conditions. In addition, the ability of Salmonella to grow in tea brewed with contaminated product was examined. A cocktail of four Salmonella serovars was inoculated onto 1 g samples of chamomile, peppermint, and green tea to give a starting cell population of approximately 10 log cfu/g. The inoculum was allowed to dry prior to storage at 25 °C and 35 °C and at low (<30% RH) and high (> 90% RH) humidity levels. At different time intervals up to 6 months, triplicate samples at each condition were evaluated for surviving Salmonella populations. In addition, samples were used to produce a low-temperature (sun) brewed tea and inoculated. Growth was assessed after 24 hr. Under the four storage conditions tested, survival followed the order 25°C/low RH > 35°C/low RH > 25°C/high RH > 35°C/high RH. Salmonella losses at 25°C/low RH occurred primarily during drying, after which populations showed little declines over 6 months. In contrast Salmonella decreased below detection after 45 days at 35°C and high RH in all teas tested. All teas tested supported the growth of Salmonella after brewing. Storage conditions significantly impact the survival of Salmonella in dried herbal teas. If Salmonella survives after storage, it may also survive and grow after a home brewing process.
M.S. in Food Safety and Technology, May 2013
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- Title
- IN VITRO STUDIES OF VIRULENCE SUPPRESSION ON P. AERUGINOSA BY PHOSPHATE / POLYPHOSPHATE-LOADED NANOPARTICLES
- Creator
- Yin, Yushu
- Date
- 2015, 2015-07
- Description
-
Critically ill patients harbor multi-drug resistant pathogens that can activate their virulence in the response to low nutrient conditions and...
Show moreCritically ill patients harbor multi-drug resistant pathogens that can activate their virulence in the response to low nutrient conditions and host stress derived factors. It was recently shown that the oversupply of inorganic phosphate to bacterial environment can profoundly suppress the virulence of pathogens. Here we hypothesized that phosphateand/ or polyphosphate-loaded nanoparticles can present a tool to deliver and slowly release phosphate in pathogen-rich niche, thereby suppressing bacterial virulence. In this work, a designed study on effect of different phosphate levels (including the phosphate released from hydrogel nanoparticles) on virulence of P. aeruginosa is addressed. In this work, we developed formulations for preparing hexametaphosphate-loaded nanoparticles on the basis of that for phosphate loaded nanoparticles. We utilized inverse miniemulsion polymerization in the synthesis of these nanoparticles. Polyethylene glycol diacrylate (PEGDA, moleculat weight of 575 Da) and N-vinyl pyrrolidone (molecular weight: 111.14 Da ) were chosen to be the initial monomers because the main crosslinker, polyethylene glycol is a kind of biocompatible material that has been approved by the U.S. Food and Drug Administration (FDA). Several parameter could be adjusted among the experiment. We selected the monomer mole fraction of PEGDA-575 as our parameter. After the synthesis, a nanoparticle size distribution between 110 nm and 150 nm was obtained. And these nanoparticles were proved to be able to release phosphate and hexametaphosphate as drug molecules. Although there were release bursts in the test of release kinetics, the crosslink density could be adjusted in following researches. The second part of this study is to test the virulence suppression effect of the nanoparticles in in vitro experiment on a kind of opportunistic pathogen, P. aeruginosa. This kind of gram-negative bacteria is one of the common intestinal microbial communities. We presented the strategy of suppressing virulence while containing rather than killing the bacteria. As a result, polyphosphate loaded nanoparticles showed to be the most effective one among several experiment groups. This result gave this study a promising future in further research in several aspects, such as in vivo test in biomedical and biomedical engineering.
M.S. in Chemical Engineering, July 2015
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- Title
- Transients on transmission lines and modern protective devices
- Creator
- Muelleman, Joseph P., Smely, James
- Date
- 2009, 1920
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/transientsontran00muel
Thesis (B.S.)--Armour Institute of Technology