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Pages
- Title
- Multivariate statistical methods for monitoring continuous processes: Assessment of discrimination power of disturbance models and diagnosis of multiple disturbances
- Creator
- Raich, A. C., Cinar, A.
- Date
- 1995-11
- Publisher
- ELSEVIER SCIENCE BV
- Description
-
A new methodology was reported [1,2] for integrated use of principal components analysis (PCA) and discriminant analysis in order to determine...
Show moreA new methodology was reported [1,2] for integrated use of principal components analysis (PCA) and discriminant analysis in order to determine out-of-control status of a continuous process and to diagnose the source causes for abnormal behavior. Most of the disturbances were identified with good rates of success, with a higher success rate for step or ramp type of disturbances. Quantitative tools that evaluate overlap and similarity between high-dimensional PCA models are proposed in this communication, and their implications on determining the discrimination power of PCA models of processes operating under disturbances are discussed. Diagnosis of several disturbances occurring simultaneously is also investigated. The criterion developed provide upper limits of discrimination power of various single and multiple process disturbances. The techniques developed are illustrated by assessing the process described by the Tennessee Eastman Control Challenge problem [3].
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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
- NEUTRON PRODUCTION IN THE M2 MUON BEAM LINE AT CERN
- Creator
- Draeger, Emily
- Date
- 2014, 2014-05
- Description
-
Spallation neutrons produced from cosmic ray muons are a major source of backgrounds in underground physics experiments. Experiments have been...
Show moreSpallation neutrons produced from cosmic ray muons are a major source of backgrounds in underground physics experiments. Experiments have been done to study spallation neutron production and yield, but our understanding of these processes is still limited. There are various interactions that can produce spallation neutrons. Most of these production mechanisms are fairly well understood; much of the uncertainty in our understanding of spallation neutrons lies in mechanisms such as virtual photon exchange and the assumptions used to calculate the photonuclear cross section. Even the experiments that have been carried out do not agree with each other or theoretical calculations. Spallation neutron production mechanisms are discussed, as well as a new experiment to study spallation neutrons. The impact of this study on current and future underground physics experiments is also explored.
PH.D in Physics, May 2014
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- Title
- INTELLIGENT PROCESS-CONTROL WITH SUPERVISORY KNOWLEDGE-BASED SYSTEMS
- Creator
- Kendra, S. J., Basila, M. R., Cinar, A.
- Date
- 1994-06
- Description
-
The integration of a supervisory knowledge-based system (KBS) with a multivariable control system is examined to provide robust multivariable...
Show moreThe integration of a supervisory knowledge-based system (KBS) with a multivariable control system is examined to provide robust multivariable control of a chemical reaction process. The supervisory KBS is capable of monitoring the process to detect system faults as well as assessing control system performance. If a control system performance deficiency is detected, the KBS formulates and implements the necessary corrective controller tuning. This adaptive capability reduces the conservatism of the robust control system. The underlying mechanisms are discussed and the re-tuning ability of the KBS is illustrated by using rigorous simulations of a chemical reaction process
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- Title
- Planning the 21st Century Urban Farm: From High Rise to Neighborhood (sequence unknown), IPRO 336 - Deliverables: IPRO 336 Final Report F09
- Creator
- Bhatti, Talha, Binet, Adrien, Bredau, Jason, Chen, Emily, Davis, Jacob, Gaonkar, Gaurav, Garcia, Raul, Guerrero, Fernando, Gulling, Richard, Kagehiro, Michael, Moshfeghian, Elnaz, Nunez-gimeno, Jose, Phillips, Zachary, Plumb, Isaac, Ryan, Emily, Skaggs, Jake, Sobon, Konrad, Valmores, Travis
- Date
- 2009-12
- Description
-
The purpose of this IPRO is to establish a strong foundation for the future of urban agriculture. The growing problems regarding the...
Show moreThe purpose of this IPRO is to establish a strong foundation for the future of urban agriculture. The growing problems regarding the traditional methods of agriculture, and the rate of growth of the world population, the team plans to design a method to grow food more efficiently and economically in urban areas. The team is looking at large, industrial warehouse-type buildings that have outlived their primary use, and creating a plan that utilizes these buildings to grow enough food for the surrounding communities.
Sponsorship: John Edel of Bubbly Dynamics, LLC
Deliverables for IPRO 336: Planning the 21st Century Urban Farm: From High Rise to Neighborhood for the fall 2009 semester
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- Title
- Planning for Human Implantation of a Cortical Visual Prosthesis (sequence unknown), IPRO 334 - Deliverables
- Creator
- Bern, David, Chen, Shanyl, Deroo, Mary, Gorski, David, Kelly, Thomas, Leasenby, Alex, Li, Zhi, Pyrkh, Hanna, Subhani, Maham, Taneja, Aanchal
- Date
- 2009-12
- Description
-
The Intracortical Visual Prosthesis is based upon that concept that by implanting a large number of subminiature electrodes within the human...
Show moreThe Intracortical Visual Prosthesis is based upon that concept that by implanting a large number of subminiature electrodes within the human visual cortex, coordinated temporal-spatial image information can be artificially communicated to the human visual cortex in the form of electrical currents, acting as a sensory substitute for normal vision.
Sponsorship: IIT Laboratory of Neural Prosthetic Research
Deliverables for IPRO 334: Planning for Human Implantation of a Cortical Visual Prosthesis for the fall 2009 semester
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- 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
- NOVEL FAULT DIAGNOSTIC TECHNIQUE AND UNIVERSAL SENSOR FOR PERMANENT MAGNET ELECTRIC MACHINES USING SEARCH COILS
- Creator
- Da, Yao
- Date
- 2012-04-23, 2012-05
- Description
-
Over the past decade, permanent magnet synchronous machines (PMSMs) have gained significant popularity in industry, such as wind turbines and...
Show moreOver the past decade, permanent magnet synchronous machines (PMSMs) have gained significant popularity in industry, such as wind turbines and electric vehicles, owing to their high efficiency, high output power to volume ratio, and high torque to current ratio. In these mission critical applications, an unexpected fault or failure of the machine could lead to very high repair or replacement cost, or even catastrophic system failure. Therefore a robust and reliable health monitoring and fault diagnostic approach is desired, which could help in scheduling preventive maintenance to lengthen their lifespan and avoid machine failure. This dissertation presents a novel multi-faults diagnostic approach using search coils. These search coils are wound around armature teeth, so they typically need to be installed during manufacturing. But its immunity to high frequency harmonics makes it suitable for inverter/rectifier fed motors or generators, such as wind turbines and automotive systems. In addition, this method does not require the knowledge of proprietary constructional details of the machine. Since the electromagnetic flux is directly measured in this method, it provides much more information than any other scheme: the direction of eccentricity and the location of shorted windings. Furthermore, this method is also capable of evaluating the severity of each fault, which is of significant importance in mission critical applications such as automotive, aerospace and military applications. In addition to these uses, the search coils can be used as a universal sensor to estimate phase current or rotor position, which are critical information in a PMSM close-loop control, which allow it to work as a backup sensor for fault tolerant operation. The proposed fault detection scheme and universal sensor concept have been tested under several scenarios with Finite Element Analysis and experimentally validated.
Ph.D. in Electrical Engineering, May 2012
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- Title
- CELL-MATRIX INTERACTIONS IN ADIPOSE TISSUE FUNCTION
- Creator
- Vaicik, Marcella K.
- Date
- 2015, 2015-07
- Description
-
The overall goal of this work is to apply in vivo and in vitro models to study the basement membrane protein laminin α4 (lama4) in adipocyte...
Show moreThe overall goal of this work is to apply in vivo and in vitro models to study the basement membrane protein laminin α4 (lama4) in adipocyte function. Adipose tissue accumulation, lipogenesis, and structure were examined in mice with a null mutation of the lama4 gene (Lama4−/−) and compared to wild-type animals (Lama4+/+). The Lama4−/−mice phenotype was investigated to evaluate if the differences were due specifically to the adipose tissue function. Physical activity and food intake does not differ between Lama4+/+ and Lama4−/− mice. However, Lama4−/− mice have a significantly increased metabolic rate at 25°C and 16°C compared to Lama4+/+ mice. In contrast, in thermoneutral conditions at 30°C both Lama4+/+ and Lama4−/− mice exhibit equivalent metabolic rates. Interestingly, when room temperature housed mice fat pads were evaluated with immunohistochemistry, Lama4−/− mice exhibit significantly increased UCP-1 expression in subcutaneous adipose. These results suggest that beiging, white to brown adipocytes, in subcutaneous adipose tissue in Lama4−/− mice may lead to decreased adipose tissue accumulation and improved metabolic function. While animal models indicate the absence of lama4 results in more beiging in subcutaneous adipose tissue, an in vitro tissue engineered model was developed to study the adipocyte function in a controlled microenvironment. Primary cell spheroids developed from Lama4+/+ and Lama4−/− were incorporated into synthetic poly(ethylene glycol) (PEG) hydrogels within a range of stiffnesses. When the cells were given the same chemical cues their functions differed depending upon microenvironment stiffness. Beige function in adipocyte cells in 3D can be influenced by matrix stiffness. In conclusion, the laminin alpha 4 basement membrane protein absence in adipose tissue results in adipocyte functional changes in vivo. The Lama4−/− mice have resistance to diet induced weight gain and increased metabolic rate at room temperature and when cold challenged. The Lama4−/− mice had increased beiging in the subcutaneous depot. Additionally, a tissue engineered model was developed to further study cell-ECM interactions first identified in an animal model. These in vivo findings and the engineered model of adipose tissue have great potential for studying obesity and other adipose related diseases. Future work will require continued interdisciplinary collaboration towards the successful identification and screening of novel therapeutics using engineered tissue models.
Ph.D. in Biomedical Engineering, July 2015
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- Title
- Financial Incubators, India: panel copy
- Creator
- Shah, Shruti
- Date
- 2010-05-01, 2010-05
- Title
- Developing Web Applications for the Northern Illinois Hockey League (sequence unknown), IPRO 308 - Deliverables: IPRO 308 Midterm Presentation F09
- Creator
- Lucchesi, Kristin, Barksdale, Dustin, Hays, Julian, Bartus, Kryzystof, Perkins, William, Savage, Christopher, Scheer, Colin, Semenov, Vladimir, Vidutis, Mantas
- Date
- 2009-12
- Description
-
The NIHL is the largest hockey league in Illinois. It is also the largest youth all star hockey league in the US, serving over 300 youth teams...
Show moreThe NIHL is the largest hockey league in Illinois. It is also the largest youth all star hockey league in the US, serving over 300 youth teams and over 4,000 players. The team's purpose is to make the NIHL a web-based scheduling and scoring applications that can support their annual operations.
Sponsorship: Northern Illinois Hockey League(NIHL)
Deliverables for IPRO 308: Developing Web Applications for the Northern Illinois Hockey League for the fall 2009 semester
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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
- BOUNDING ESTIMATION INTEGRITY RISK FOR LINEAR SYSTEMS WITH STRUCTURED STOCHASTIC MODELING UNCERTAINTY
- Creator
- Langel, Steven Edward
- Date
- 2014, 2014-05
- Description
-
Safety critical estimation applications require quantification of integrity risk, which is the probability of the state estimate error...
Show moreSafety critical estimation applications require quantification of integrity risk, which is the probability of the state estimate error exceeding predefined bounds of acceptability. Integrity risk can only be evaluated when the state estimate error probability density function is precisely known, necessitating stochastic models that exactly describe measurement noise and disturbance inputs. Uncertainty in these models directly results in inaccurate assessments of integrity risk. This dissertation develops the first implementable methods to upper bound integrity risk when the autocorrelation functions of stochastic inputs reside between upper and lower bounding functions. The first part of this work considers real-valued estimation applications that use the Kalman filter or batch weighted least squares estimator. Explicit relations are developed between the estimate error variance and autocorrelation functions using a new generalized covariance matrix derived in this dissertation. From these expressions, two methods are provided to upper bound integrity risk. The first method enables fast computation of a conservative bound, and the second method produces the minimum upper bound via semi-definite optimization. Mixed real/integer estimation applications utilizing integer bootstrapping are the focus of the second part of this work. The integrity risk bound is formally defined as the global solution to a non-convex optimization problem over a polytope. Determination of the polytopic region is difficult, and two bounding approaches are initially developed for a circumscribing hyper-rectangular feasible region. Using an innovative method to define the polytope together with linear programming, a third method is derived to upper bound integrity risk over the true polytopic feasible region.
PH.D in Mechanical and Aerospace Engineering, May 2014
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- Title
- PA 508 Student Computer Usage Survey: PA508 Student Survey 2010 Results
- Creator
- Ahrens, Aric G.
- Date
- 2010-01-19, 2010-01-19
- Description
-
Included are a survey, and the results in graphic form. The survey was designed to find out how and where the Chinese contingent of Master of...
Show moreIncluded are a survey, and the results in graphic form. The survey was designed to find out how and where the Chinese contingent of Master of Public Administration students used computers. The focus was to determine whether they preferred to use computers on the Downtown Campus, where classes were taught, or on Main Campus, where most of the students lived.
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- Title
- Teacher Knowledge Share (Semester Unknown) IPRO 320: Teacher Knowledge Share IPRO 320 MidTerm Presentation F08
- Creator
- Bern, David, Bochantin, Marike, Hartline, Julian, Mccall, Ian, Mick, Emily, Peake, Andrew, Pierce, Alison, Pindrik, Dmitriy, Quinn, Michael, Stanford, Carly, Tilatti, Michael
- Date
- 2008, 2008-12
- Description
-
The goal of IPRO 320 is to create an online professional network for school teachers at the kindergarten through twelfth grade level to allow...
Show moreThe goal of IPRO 320 is to create an online professional network for school teachers at the kindergarten through twelfth grade level to allow for the sharing of ideas, lesson plans and other professionally relevant information. This is a continuing project which saw limited success in the previous semester in that a functioning web site was constructed based on surveys of public school teachers but it saw very little use. This semester, the planned approach is to build on the research generated last semester by performing additional market research with teachers. Following that, IPRO 320 will rework much of the previous web site by refining some of the features, adding additional ones as the research indicates and improving the website in general, both functionally and aesthetically.
Deliverables
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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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