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- Title
- DEVELOPMENT AND VALIDATION OF A HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC METHOD FOR SIMULTANEOUS DETERMINATION OF VITAMINS A AND D IN FLUID MILK PRODUCTS
- Creator
- Li, Wenjing
- Date
- 2013, 2013-12
- Description
-
Measurement of fortification levels for vitamins A and D in fluid milk products is required by the U.S. Food and Drug Administration (FDA)...
Show moreMeasurement of fortification levels for vitamins A and D in fluid milk products is required by the U.S. Food and Drug Administration (FDA) according to Pasteurized Milk Ordinance. In the current study, a high performance liquid chromatographic (HPLC) method was developed for simultaneous determination of retinyl palmitate (vitamin A) and cholecalciferol (vitamin D3) in fortified milk, which will enhance the efficiency of routine monitoring of fortification for processors as well as laboratories. Saponification conditions and extraction solution compositions were studies for best recovery and simplification of the extraction procedures. Saponification conditions studied included temperature (20, 40 and 60℃), time (0.5 to 16 hour) and concentration of KOH (20, 30, 40 and 50%). The variables studied for extraction included solvent compositions (hexane, diethyl ether, ethyl acetate and dichloromethane) and corresponding polarities (0.1, 0.25, 0.5 and 0.75), and number of extractions (once, twice and three times). Freezing and centrifuging steps were also investigated to compare to SPE clean-up, as an alternative method to clean-up before injection. The optimum parameters found were: saponification conditions at 60℃ for 2 hours with 40% (w/v) KOH liquid-liquid extraction with hexane: diethyl ether (80:20, v:v). Vitamins A and D3 were quantitated using an HPLC system with fluorescence detector (FLD) and diode array detector (DAD) respectively within the same injection. Spike recoveries from three different fat levels (skim, 2% and whole) of commercial pasteurized milk samples were in the range of 94 to 110% for both vitamins A and D3 at three spike concentration levels. In addition, at National Institute of Standards and Technology (NIST) Standard Reference Material (SRM 1849a) was used xii for method accuracy evaluation. With eight replicates, the average vitamin A (expressed as retinol equivalents) concentration was 7.52 ± 0.23 μg/g, vitamin D3 concentration was 0.114 ± 0.0062 μg/g, an excellent agreement with the certified value of 7.68 ± 0.23 μg/g for vitamin A and 0.11 ± 0.017 μg/g for vitamin D3. In summary, an HPLC method for simultaneous determination of vitamins A and D3 in fluid milk products has been developed. The method showed high efficiency and accuracy of analysis during a single laboratory validation.
M.S. in Food Safety and Technology, December 2013
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- Title
- OPTIMAL MATERIAL SELECTION MODEL FOR LEED CERTIFICATION USING GENETIC ALGORITHMS
- Creator
- Kim, Taehyoung
- Date
- 2012-12-16, 2012-12
- Description
-
Material selection is an important part of building design because it has great impact on the environment, as buildings during/after...
Show moreMaterial selection is an important part of building design because it has great impact on the environment, as buildings during/after construction are responsible for a large portion of carbon emissions and use many resources and considerable energy. Selecting green materials is an emergent issue in both design firms and construction companies. Green building certification such as LEED systems originated from the desire to improve environmental, economic, financial, and social benefits. The current approach to material selection for sustainability is based only on the designer’s past experiences. An arbitrary approach based on subjective opinions causes unnecessary expense, longer construction duration, and failure to meet desired environmental goals. In order to help decision-makers with the selection of the right materials, this study proposes a model that uses Genetic Algorithms in MATLAB and that optimizes the desired points in LEED Certification within budget constraints. This model can be applied to any project that is pursuing LEED Certification. If the user specifies the desired LEED points, the system recommends the least expensive combination of materials extracted from a database containing detailed information about a large member of materials. The modified model uses multi-objective genetic algorithms to establish trade-off between budget constraints and LEED points. The proposed system is expected to be a useful tool for inexperienced designers and a valuable guideline for designers with extensive experience.
M.S. in Civil Engineering, December 2012
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- Title
- Planning the 21st Century Urban Farm: From High Rise to Neighborhood (sequence unknown), IPRO 336 - Deliverables
- 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
- BUOY (Semester Unknown) IPRO 310: BUOYIPRO310Brochure2Sp09
- Creator
- Baar, Coleman, Freund, Ryan, Kruse, Kevin, Li, Li, Ma, Zhi, Murdock-barriball, Meghan, Ng, Man, Rehman, Mohammed, Reilly, Jeffrey, Turrentine, Lorne, Yew, Hsuen, Zhang, Bingjian
- Date
- 2009, 2009-05
- Description
-
The problem posed with blind and visually impaired (BVI) swimmers is one of safety and independence. BVI individuals need to be able to...
Show moreThe problem posed with blind and visually impaired (BVI) swimmers is one of safety and independence. BVI individuals need to be able to orientate themselves in a swimming pool and avoid obstructions like lane-lines, pool walls and other swimmers for a safe experience. Additionally, it is important to BVI swimmers to maintain their independence and maintain a low profile during this experience. The Buoy team will focus on the design, testing and implementation of assistive technology focused on a pool environment with continuous input and feedback from the BVI community. A current passive device created in previous IPROs will be field-tested in a BVI pool for the semester in order to identify failure-modes of the device and collect real-world BVI user feedback to discover areas for improvement. Additionally, two groups have been organized to assess the use of invisible-fence and ultrasound technology in the creation of new assistive technology. Surveys and interviews will be conducted with the BVI community on a continuous basis to ensure the Buoy team is meeting the needs of the market.
Deliverables
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- Title
- Small Town Sustainable Economic Development Feasibility of a Biochar System in Orange, Massachusetts (Semester Unknown) IPRO 350: SmallTownSustainableEconomicDevelopmentIPRO350FinalPresentationSp11
- Creator
- Adejinle, Remi, Butail, Gokul, Cosenza, Samantha, Graaff, Tillman De, Futagami, Takahiro, Hinshaw, Ben, Khan, Asfandyar, Latour, Catherine, Lee, Brandon, Stewart, Dashiell, Wang, Yani
- Date
- 2011, 2011-05
- Description
-
The purpose of the team is to design a model of a sustainable waste management system for the town of Orange, Massachusetts. We seek to foster...
Show moreThe purpose of the team is to design a model of a sustainable waste management system for the town of Orange, Massachusetts. We seek to foster the economic attractiveness and vitality of the town by designing a better and more sustainable way to manage the town’s waste.
Sponsorship: Town of Orange, Massachusetts
Deliverables
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- Title
- Kalleidos (Spring 2011) IPRO 303: KalleidosIPRO303ProjectPlanSp11_redacted
- Creator
- Rakauskaite, Ausrine, Siver, Ben, Pyrkh, Hanna, Kovacs, Hilary, Jewell, John, Jin, Keojin, Arroyo, Marcos, Michael, Mark, Koto, Melanie, Curran, Morgan, Kushaare, Rishi, Ri, Sujin, Liu, Xiaochen
- Date
- 2011, 2011-05
- Description
-
“Over the last few years there has been an explosion of different websites that allow average person to contribute different content such as...
Show more“Over the last few years there has been an explosion of different websites that allow average person to contribute different content such as pictures, comments, stories and reviews about places around them. While there are many companies that focus on aggregating such data into common stream - complexity of interpreting such data in a meaningful actionable way remains a challenge for many companies including NAVTEQ.” [Appendix B] Identify new content from real time feeds which include 1. Points of Interest and their attribution (e.g. Hours of Operation, Languages Spoken at locale, etc…) 2. Any associated content (e.g. events, relationships to other Points of Interest (e.g. same owner, etc…) Create visualizations based on this content - some basic examples could include 1. Hot/Not So Hot real estate areas (new construction, sales) based on agent and broker social media updates 2. High/Low crime areas based on social media stream 3. Hot/Not city zones based on number of people tweeting/updating Facebook/checking in/etc… in certain areas, parties, POIs.
Sponsorship: NAVTEQ
Deliverables
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- Title
- Insight: Anticipating the Future, Assessing the Impact (semester?), IPRO 341: Insight IPRO 341 IPRO Day Presentation F06
- Creator
- Bastyzyk, Marta B., Hernandez, Jose, Kim, Tae Young, Lerash, Kevin, Lybolt, Crystal, Seatton, Brandon, Skontos, George, Sopko, Tyge, Vaks, Nir, Agan, Amber, Boone, Elizabeth, Buente, Adam, Coleman, Jessica, Gerding, Eric, Glass, Andrew, Goyak, Matt, Holt, Nicole, Mullendore, Jessica, Perchlik, Emily, Ripley, Paul
- Date
- 2006-12, 2006-12
- Description
-
IPRO 341’s objective is to extensively research and evaluate the societal, economical and environmental implications of nanotechnology-based...
Show moreIPRO 341’s objective is to extensively research and evaluate the societal, economical and environmental implications of nanotechnology-based products, mainly building materials, and detail the possible obstacles in integration of this technology into design, public policy issues and general public engagement
Deliverables for IPRO 341: Insight: Anticipating the Future, Assessing the Impact for the Fall 2006 semester
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- Title
- Assisting Cardiac Arrest Patients (Semester Unknown) IPRO 319: Assisting Cardiac Arrest Patients IPRO 319 Final Presentation F08
- Creator
- Alemayehu, Matti, Bunce, Alex, Jessica, Shaw, Toe, Myint, Untiveros, Gustavo, Zhang, Caidi, Jose, Jerry, Butkovich, Paul, Cosenza, Matthew, Martin, Rebecca
- Date
- 2008, 2008-12
- Description
-
Sudden Cardiac Arrest is a leading cause of death in the United States, accounting for an estimated 325,000 deaths each year according to the...
Show moreSudden Cardiac Arrest is a leading cause of death in the United States, accounting for an estimated 325,000 deaths each year according to the Heart Rhythm Foundation. Cardiac arrest is different from a typical heart attack because it involves a complete stopping of the heart. Brain injury is likely to occur if the cardiac arrest is untreated for more than 5 minutes and a person cannot be revived after 10 minutes of no action. This is because the arrest sets off a chain of metabolic reactions, which leads to swelling of the brain tissue. Cardiac arrest results in ischemia reperfusion injury, which is when circulation is restored and high levels of oxygen rich blood rushes back into the brain causing brain damage. Decreasing the metabolism of the victim may result in a decrease of ischemia reperfusion injury. Reducing the oxygen level that enters the body when the victim revives and slowly increasing this level may also reduce reperfusion injury. However, current procedures dictate that 100% oxygen be given to cardiac arrest victim.
Deliverables
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- Title
- Alumni Memorial Hall Renovation (Semester Unkown) IPRO 335: Alumni Memorial Hall Renovation IPRO 335 Final Presentation Sp08
- Creator
- Denney, Thomas, Ericksen, Michael, Forkan, Garret, Healy, Kieran, Hong, Ei Sheng, Kim, Yong-wan, Kirk, Justin, Ontiveros, Adrian Jesus, Rogers, Eric, Roth, Nathaniel, Sharadendu, Dipti, Sissala, Amy, Warner, Alexander, Weston, Brad
- Date
- 2008, 2008-05
- Description
-
The scope of I-Pro 335 is both a conclusion to unfinished work from the previous two semesters along with new projects that will start and end...
Show moreThe scope of I-Pro 335 is both a conclusion to unfinished work from the previous two semesters along with new projects that will start and end this semester. Work to be concluded and closed-out from last semester: Final LEED (Leadership in Energy and Environmental Design) documentation and identification of individuals that might be part of a LEED team should the school desire to pursue that route. Final design of Americans with Disabilities Act (A.D.A.) elements including a re-design of the elevator, and approval by the client. Using the Code of Ethics written last semester as a base line, the code will be rewritten to strengthen its objective to provide guidance for the I-Pro. New projects to begin and completed this semester are: The roof re-design- Green roof options. This may also include storm water retention and grey water recycling systems, as well as any updates to the buildings primary plumbing systems. Heating, Ventilation, and Air Conditioning (HVAC) - Lab hoods, air conditioning load calculations and Hydronic Heating. Electrical systems design- Illumination calculations and design, Alarm systems, and ‘Off-heating’ load calculations from equipment to be housed in Alumni Memorial Hall (A.M.H.). Construction schedule. Cost estimate.
Deliverables
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- Title
- Large Scale Structure Design (Semester Unknown) IPRO 315
- Creator
- Brady, Brian, Butkovich, Paul, Chung, Chun, Dominikowski, Marek, Herbert, Greg, Hussaini, Muddasir, Magdel, Irina, Mallinger, Nicolle, Omeralovic, Enis, Palma, Jennifer, Rathakrishnan, Malar, Ratnani, Shoaib, Russeva, Diyana, Russo, Ben, Shim, Mary, Sisay, Mary, Varhegyi, Aron, Velichekov, Veselin
- Date
- 2008, 2008-05
- Description
-
The plan for this IPRO is to develop a design for a large scale parking garage that can accommodate about 500 cars. The objective of this...
Show moreThe plan for this IPRO is to develop a design for a large scale parking garage that can accommodate about 500 cars. The objective of this project is to develop a design that goes beyond the standard parking systems used today. Rather, the attempt is to have a design which is more representative of “parking garages of future.” And as such, such features as quick handling of incoming and outgoing cars, efficiency in storage and aesthetics are considered in design. The building will be completely self-sufficient and will have to incorporate the architecture of the various buildings on campus. The design could have separate entrance and exit ramp towers, ramps incorporated with parking, or the futuristic design may be automated. An automated system will include a vehicle elevator of lift system to move the vehicle so the driver does not have to. The structure could be built with reinforced concrete or steel. The design will also include accessibility following the requirements set forth in the Americans with Disabilities Act.
Deliverables
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- Title
- Interdisciplinary Design Education And Strategy (Semester Unknown) IPRO 301: InterdisciplinaryDesignEducationAndStrategyIPRO301Poster1Su09
- Creator
- Scanlon, Ed, Brierley, Philip, Choe, Mihee, Cornelius, Joel, Hansen, Kai, Horozova Nalls, Gergana, Hussain, Faraz, Krupp, Kevin, Laurence, Alexis, Lucchesi, Kristin, Mceneff, Aaran, Natale, Vito, Nikamalfard, Mehrdad, Phillips, Timothy, Radtke, Dennis, Robledo, Ruben, Workman, Jessica, Valadez, Julia
- Date
- 2009, 2009-07
- Description
-
For years, the IPRO Program at IIT has been forced to operate wherever space can be found. Often, facilities are not equipped for the needs of...
Show moreFor years, the IPRO Program at IIT has been forced to operate wherever space can be found. Often, facilities are not equipped for the needs of the program. It has become necessary to find a way to give the IPRO Program its own dedicated space. If we give the program its own space, then what is needed in that space? What needs to be done with it? What types of spaces are necessary? What technologies will be used? IPRO 301 exists to answer these questions. We will provide ideas to IIT that can solve these problems. ii
Deliverables
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- Title
- TravelFlash (semester?), IPRO 350: Travel Flash IPRO 350 IPRO Day Presentation F04
- Creator
- George, Sherine, Raju, Betsy, Campion, Nicholas, Dabney, Matt, Ostapczuk, Alexander
- Date
- 2004-12, 2004-12
- Description
-
The goal of the IPRO 350F04- Travel Flash team is to perform a feasibility analysis of the electronic travel guide idea. The team plans to...
Show moreThe goal of the IPRO 350F04- Travel Flash team is to perform a feasibility analysis of the electronic travel guide idea. The team plans to attain its goals by performing a competitive analysis of the existing market for travel guides, analyzing the technology for this particular idea and to do a focus group to receive feedback and input for desirable features. The vision is to do a thorough analysis of the idea to determine if it warrants further investment of this team.
Sponsorship: Sky Blue Mobile; Ed Kaplan Entrepreneurial Studies Program
Deliverables for IPRO 350: TravelFlash for the Fall 2004 semester
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- Title
- BP Whiting Refinery Expansion: Developing Lake Michigan Wastewater Cleanup Options (Semester Unknown) IPRO 346: BP Whiting Refinery Expansion IPRO 346 Project PlanSp08
- Creator
- Ashrafi, Sahar, Ballard, Ray, Chock, Chris, Chung, Yak Yong, Fakhouri, Hana, Ferrese, Anthony, Fernando, Fernando, Haak, Laura, Hammes, Katherine, Kim, Jichul, Leasenby, Alex, Lewis, Richard, Li, Zhi, Malon, David, Michael, Henry, Park, Miri, Reimann, Kirsten, Roberts, Ben, Song, Jong Mu, Taracena, Willy, Truong, Josie, Ucci, Russel, Vassi, Anna, Walter, Michael, Witek, Andrew, Yoo, Jaewon, Zhao, Yin
- Date
- 2008, 2008-05
- Description
-
IPRO346 will focus on familiarizing itself with British Petroleum’s (BP) wastewater treatment plant (WTP) for its oil refinery in Whiting, IN....
Show moreIPRO346 will focus on familiarizing itself with British Petroleum’s (BP) wastewater treatment plant (WTP) for its oil refinery in Whiting, IN. Specifically, this IPRO will analyze the current permits and their stipulations regarding the amount of ammonia and total suspended solids (TSS) in the wastewater being dumped in Lake Michigan. Ultimately, possible methods and designs will be devised to reduce the levels of ammonia and TSS remaining in treated wastewater. These designs will take the form of a process flow sheet with a computer simulation to model the designs. At the culmination of this IPRO we will have several different models for possible upgrades to the Whiting refinery wastewater treatment plant to reduce the levels of ammonia and TSS in the wastewater entering Lake Michigan as well as a cost to implement each solution.
Deliverables
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- Title
- Development Plan For The Michael Reese Site (Semester Unknown) IPRO 359
- Creator
- Beardsley, Erin, Grace, Heather, Masangkay, Rodolfh, O'brien, Patrick, Van Eaton, Justin, Weissman, Kathryn, Champlin, Austin, Lockowski, Wesley, Morgenthaler, Maximillian, Salisbury, Joshua, Waisath, Nathan, Chun, Amy, Knapczyk, Robert, Nguyen, Nam, Slonski, Bryan, Wang, Ruoxi
- Date
- 2010, 2010-05
- Description
-
Our team purpose is to develop a project on the site of the old Michael Reese Hospital that develops the community, brings in revenue,...
Show moreOur team purpose is to develop a project on the site of the old Michael Reese Hospital that develops the community, brings in revenue, attracts development and revitalizes the surrounding areas. Our mission is to design something that attracts people and businesses through unique and innovative opportunities, as well as to establish a community where people can grow and develop leadership.
Deliverables
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- Title
- Study of the production of resorcin
- Creator
- Cable, D. E., Prest, J. I.
- Date
- 2009, 1918
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/studyofproductio00cabl
Thesis (B.S.)--Armour Institute of Technology
- Title
- 2B Developed EnPRO 351
- Creator
- Vinson, Robert, Cunningham, Ryan, Mccall, Ian, Peake, Andrew, Alonso, Jesus, Kim, Min Seung, Hasija, Abhinav, Morales, Antonio, Kim, Jeong Shik
- Date
- 2008, 2008-05
- Description
-
It is our objective to create a medium in which to combine the need of proficient web developers for university projects/ jobs as well as...
Show moreIt is our objective to create a medium in which to combine the need of proficient web developers for university projects/ jobs as well as others looking for similar services outside of the university, with IIT students looking to gain experience as well as payment, whether through class credits or through wages. We plan to create a business model of a consulting firm that seeks out clients, as well as having clients brought to the firm, realize their needs, create a design document of their proposed website, then seek out the students with the capabilities matching the clients needs and “hire” them for the job, all the while maintaining that the quality of the student’s work will be sufficient to the client and therefore sufficient for our consulting firm. The start up companies/clients we gain will receive knowledge, expertise, and fresh ideas for a much needed website for their company/project. On the other hand the students will receive real-life experience working for a client in a certain timetable, with a standardized set of guidelines while also receiving some form of compensation.
Deliverables
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- Title
- Create a Science Fair Archive for Chicago Public High School Students (semester?), IPRO 330: CPS Science Fair Project Bank IPRO 330 IPRO Day Presentation Sp07
- Creator
- Beagley, Jonathan, Yokley, Kevin, Hill, Shayne, Parillo, Tony, Dunne, Brian, Holt, Tom, Ji, Chaonan, Meyer, Chad, Mccourt, Michael, Shenoy, Pradeep, Sikoeski, Kajetan
- Date
- 2007-05, 2007-05
- Description
-
The focus of IPRO-330 is to help Chicago Public Schools facilitate the district wide science fair project. Each semester each of the 23 public...
Show moreThe focus of IPRO-330 is to help Chicago Public Schools facilitate the district wide science fair project. Each semester each of the 23 public high schools in our district hold science fairs within their school. The best projects are selected from these and are chosen to compete at the district science fair; this competition was held at IIT this year.
Deliverables for IPRO 330: Create a Science Fair Archive for Chicago Public High School Students for the Spring 2007 semester
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- Title
- Fuel Cells for Unmanned Undersea Vehicles (Semester Unknown) IPRO 349: FuelCellDesignForUnmannedUnderwaterVehiclesIPRO349ProjectPlanSp10
- Creator
- Abankwa, Kevin, Ashrafi, Sahar, Ballard, Ray, Baughey, Ethan, Chaffee, Matthew, Cho, Moses, Chock, Chris, Choy, Marcus, Guilfoyle, Jennifer, Hagopian, Matthew, Kenig, Elezar, Luo, Chieh
- Date
- 2010, 2010-05
- Description
-
The goal of IPRO 349 is to produce a conceptual design of an unmanned underwater vehicle (UUV) that is powered by a fuel cell. The primary...
Show moreThe goal of IPRO 349 is to produce a conceptual design of an unmanned underwater vehicle (UUV) that is powered by a fuel cell. The primary customer in consideration for this IPRO is the US Navy. The importance of submarines has long been recognized by the military and has caused drastic changed in modern warfare.
Deliverables
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- Title
- Intermodal Transport System in Crete Illinois (Semester Unknown) IPRO 307: IntermodalContainerSystemSolutions IPRO307FinalReportF10
- Creator
- Williams, Gabriel, Woods, Bryan, Radzik, Izydor, Levin, Jeremy, Anca, Gruita, Davis, Aaron, Roth, Jessica, Allen, John, Pollack, Aaron, Bajzek, Sasha, Ahmadu, Jibril
- Date
- 2010, 2010-12
- Description
-
IPRO 307 is following the path of its predecessors in order to help improve the shipping transportations and facilities in the immediate...
Show moreIPRO 307 is following the path of its predecessors in order to help improve the shipping transportations and facilities in the immediate region, specifically Crete, IL. While there has been other IPRO teams that have contributed to the modernization of the intermodal system at My-Jack Shipping Company, our sponsor is now calling upon us again to further their research in this field.
Sponsorship: My-Jack Shipping Company
Deliverables
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- Title
- INTEGRATION OF TANGENTIAL FLOW FILTRATION AND IMMUNOMAGNETIC SEPARATION FOR RAPID DETECTION OF ESCHERICHIA COLI 0157:H7 IN PRODUCE WASH WATER
- Creator
- Ren, Yan
- Date
- 2011-12-12, 2011-12
- Description
-
Escherichia coli O157:H7 is one of the most commonly reported pathogens associated with microbial contamination of leafy greens. Since washing...
Show moreEscherichia coli O157:H7 is one of the most commonly reported pathogens associated with microbial contamination of leafy greens. Since washing is a major postharvest processing step, microbial testing of spent wash water has been suggested as a good marker to determine the contamination status of the products. In this study, the efficiency of four commercial rapid methods (BAX®, IQ-Check, Reveal® and mini-VIDAS®) for detection of E.coli O157:H7 in lettuce wash water was evaluated in comparison with the FDA BAM method. The improvement of the detection sensitivity of these tests by immunomagnetic separation (IMS) technology and sample pre-concentration by Tangential Flow Filtration (TFF) was determined. Twenty-five ml of lab prepared lettuce wash water samples were spiked with 0, 1, 10, 100 CFU of E.coli O157:H7, and subjected to enrichment protocols recommended by each of the methods. The presence of E.coli O157:H7 in the enriched samples were then assayed by the test kits, either directly or after IMS (IMS-Pathatrix ™ or IMS-Dynabeads™) treatments. All four test kits and BAM were able to detect E.coli O157:H7 at levels as low as 1 CFU/25ml of wash water. IMS treatments did not lead to further improvement in detection sensitivity. Experiments were also performed to determine the feasibility of incorporating IMS and sample pre-concentration to achieve culture-free detection. Fifty ml of wash water samples were inoculated with E.coli O157:H7 at levels of 0 to 107 CFU and analyzed by the test kits either directly or after IMS-Pathatrix™ treatment. Additionally, 10 L of wash water either prepared in the lab or collected from a commercial fresh-cut processing facility were inoculated with 0 – 106 CFU of the pathogen and subjected to TFF concentration prior to IMS or test kit analyses. IQ-Check showed the highest sensitivity with a detection limit as low as 103 CFU/50ml, and, with IMS, achieved a sensitivity of 100 CFU/50ml. Combining TFF concentration and IMS, 10 L of lab prepared wash water can be tested with IQ-Check and achieve a detection limit of approx. 100 CFU/10 L within 6 hours. For 10L of industry spent wash water, IQ-check also showed the highest sensitivity but the results lacked consistency and required additional evaluations.
M.S. in Food Safety and Technology, December 2011
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