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(561 - 580 of 2,990)
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- Title
- MULTIPLE SIGNAL TRANSDUCTION EVENTS AND MODULATION OF OLFACTORY RESPONSES IN MOUSE OLFACTORY SENSORY NEURONS
- Creator
- Yu, Yiqun
- Date
- 2012-04-30, 2012-07
- Description
-
In the mammalian olfactory system, one olfactory sensory neuron (OSN) expresses a single olfactory receptor (OR) gene. I studied two subsets...
Show moreIn the mammalian olfactory system, one olfactory sensory neuron (OSN) expresses a single olfactory receptor (OR) gene. I studied two subsets of mouse OSNs, hereafter refered to as Ho-OSNs and AB-OSNs, in intact mouse olfactory turbinates using calcium imaging. Both of Ho-OSNs and AB-OSNs were located in the most ventral olfactory receptor zone. Ho-OSNs were specifically responsive to 2-heptanone (Ho), heptaldehyde (H) and cis-4-heptenal (cH). Dose-dependent analysis indicated that their responses to individual odorant was saturated within one logarithm unit of concentrations, a typical characteristic of isolated OSNs. Binary mixture and crossadpatation studies showed that these three odorants bound to the same binding sites in Ho-OSNs. However, these three structurally similar odorants activated distinct signaling pathways in Ho-OSNs. In detail, 2-heptanone-evoked intracellular calcium elevation was mediated by AC-cAMP signaling, while heptaldehyde triggered the PLC-DAG pathway. The cis-4-heptenal-evoked [Ca2+]i increases resulted from a combination of cAMP mediated activation and suppression involving PLC signaling. Furthermore, the PLCmediated intracellular calcium alteration was independent of IP3 signaling. A further complexity is that these olfactory receptors were able to interact with other types of Gprotein coupled receptors (GPCRs), such as purinergic receptors. I determined that both the P2X3 and P2Y2 receptor subtypes were expressed in Ho-OSNs. Application of purinergic agonists elevated [Ca2+]i increases in Ho-OSNs. It was discovered that the ATP-induced calcium response required either intracellular or extracellular calcium, while depletion of intracellular calcium stores blocked the UTP-evoked [Ca2+]i increases. Purinergic agonists were able to modulate the odor response in Ho-OSNs, and purinergic antagonist experiments showed that modulation of heptaldehyde-induced calcium responses was due to activation of P2X3 receptor subtypes while heptanone-induced calcium responses was not. Although AB-OSNs were found adjacent to Ho-OSNs, they had complete separate response profiles. AB-OSNs were sensitive to acetophenone (Ace) and benzaldehyde (Ben). In AB-OSNs, both acetophenone and benzaldehyde activated the PLC signaling pathway. Pharmacological characterization indicated that in AB-OSNs, P2X1 and P2Y2 receptors were present, which is different from that in Ho-OSNs. P2X and P2Y agonists modulated odorant responses in AB-OSNs. Purinergic signaling differentially regulated the various odorant responses in AB-OSNs. The acetophenoneevoked [Ca2+]i increases were negativly modulated through activation of the P2Y2 receptor, while the calcium response induced by benzaldehyde was modulated by P2X1 receptor activation. Collectively, these studies suggest that a complex signaling mechanism exists in OSNs, which has important implications for understanding the mechanism of information process in the olfactory system.
Ph.D. in Biology, July 2012
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- Title
- Advances in Understanding Supersonic Jet Screech: Review and Perspective
- Creator
- Raman, G.
- Date
- 1998-02
- Publisher
- Pergamon - Elsevier Science Ltd
- Description
-
Screech tones are produced by imperfectly expanded jets under certain conditions. This paper provides an overview of developments in the field...
Show moreScreech tones are produced by imperfectly expanded jets under certain conditions. This paper provides an overview of developments in the field of supersonic jet screech. The overview includes a historical background, summary of recent developments, and a critical assessment of our current understanding of screech. The subject material has been categorized as described in the table of contents given below. (C) 1998 Elsevier Science Ltd.
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- Title
- The phase diagram of QCD from lattice simulations, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
- Creator
- D'elia, Massimo
- Date
- 2013-09-15, 2013-09-15
- Publisher
- IIT Press
- Description
-
Numerical simulations of Quantum Chromodynamics on a space-time lattice represent the best non-perturbative tool to explore the QCD phase...
Show moreNumerical simulations of Quantum Chromodynamics on a space-time lattice represent the best non-perturbative tool to explore the QCD phase diagram and the behavior of strong interactions under extreme conditions. We review the present status of the field and discuss some recent results.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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- Title
- Planning the 21st Century Urban Farm: From High Rise to Neighborhood (sequence unknown), IPRO 336 - Deliverables: IPRO 336 Poster 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
- PAST- AND FUTURE- ORIENTED COGNITIONS IN PTSD: THE RELATIONSHIP BETWEEN RUMINATION AND WORRY IN DEPRESSION AND ANXIETY SYMPTOMS
- Creator
- Stickney, Laurie
- Date
- 2016, 2016-07
- Description
-
Post-Traumatic Stress Disorder (PTSD) is a complex disorder characterized by symptoms of both anxiety and depression. Likewise, individuals...
Show morePost-Traumatic Stress Disorder (PTSD) is a complex disorder characterized by symptoms of both anxiety and depression. Likewise, individuals with PTSD experience Repetitive Negative Cognitions in the form of rumination and worry that may be focused on the past, present, or future. Although cognitions in individuals with PTSD have been studied, there is some question as to what types of cognitions individuals with PTSD generally experience and to what extent different types of cognitions contribute to different PTSD symptomatology. Further, although worry and rumination in PTSD have been studied, the question of the importance of the time-focus of cognitions in PTSD has not been adequately addressed. Time-focused cognitions and the relationships among depression, anxiety, rumination and worry were examined in this study using experience sampling method. Participants were asked to fill out a short survey measuring depression, anxiety, rumination, worry and time-focus five times per day for seven days. Results indicated that the presence of Current-focused cognitions strengthened the relationship between worry and anxiety compared to Future-focused cognitions. These findings suggest that in terms of the relationship between anxiety and worry, it is current-focus that is important not future-focus. Additionally, worry partially mediated the relationship between rumination and anxiety, and rumination partially mediated the relationship between worry and depression. Overall, the results suggest that time-focus may be important in some areas of PTSD, and the study highlights the complex relationships among depression, anxiety, rumination, worry and time-focused cognitions.
Ph.D. in Psychology, July 2016
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- Title
- DYNAMIC BEHAVIOR OF PERIODIC FEEDBACK-CONTROL SYSTEMS
- Creator
- Kendra, S., Cinar, A.
- Date
- 1991
- Publisher
- GORDON BREACH SCI PUBL LTD
- Description
-
Periodic feedback is a control strategy implemented by fast zero-average oscillations in the parameters of the control law. It is well known...
Show morePeriodic feedback is a control strategy implemented by fast zero-average oscillations in the parameters of the control law. It is well known that time invariant feedback control offers no means for zeros relocation. Periodic feedback allows zeros relocation in an asymptotic sense, resulting in improved closed loop characteristics, such as increased gain margins.
Endnote format citation
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- Title
- INTERNET-BASED CONTACT PROGRAMS TO FIGHT THE STIGMA OF SCHIZOPHRENIA
- Creator
- Wassel, Abigail K.
- Date
- 2014, 2014-07
- Description
-
Stigma is an insidious problem that has resulted in loss of opportunities for people with mental illness. Research suggests that contact...
Show moreStigma is an insidious problem that has resulted in loss of opportunities for people with mental illness. Research suggests that contact provided through a structured talk by a person with mental illness could serve as an effective tool in combating stigma and promoting attitude change. Additionally, research on imagined contact suggests this approach can also decrease negative stereotypes toward people with schizophrenia. The current study examined the effectiveness of these two approaches in changing attitudes toward people with mental illness when delivered via the Internet. It was hypothesized that both a videotaped contact and an imagined contact approach would increase positive attitudes and decrease negative attitudes toward people with mental illness when presented alone, and that efficacy would increase when combined. Findings showed no significant changes for any experimental condition from baseline attitudes or relative to a control condition, which suggests that interventions used in this study are not successful in creating sustainable attitude change over the Internet.
Ph.D. in Psychology, July 2014
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- Title
- A C-OMPARISON OF TWO ALGORITHMS FOR ADAPTING INTERVIEWS TO PERSONALITY SCORES
- Creator
- Van Overberghe, Courtney T.
- Date
- 2012-04-18, 2012-05
- Description
-
Two adaptive interviews – adding questions based on low or high scores from a personality assessment – were compared to a structured interview...
Show moreTwo adaptive interviews – adding questions based on low or high scores from a personality assessment – were compared to a structured interview. In a mock selection process, it was found that the adaptive and structured interviews had similar correlations with performance on a role play task. However, due to the added length of the adaptive interview, it had slightly less utility than a structured interview. A cognitive measure and the interview conditions were better predictors of performance than the personality questionnaire, which had no relationship with performance. A post-hoc analysis found that the social desirable scale from the personality instrument correlated negatively with the structured interview, the role play and the IQ test, and positively correlated with the personality composite score.
Ph.D. in Psychology, May 2012
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- Title
- Sloan Valve Company (sequence unknown), IPRO 306 - Deliverables: 306_redacted
- Creator
- Delahanty, Sean, Jaouen, Julien, Thakkar, Hetul, Jones, Santiago Guerrero, Kim, Sung, Toor, Hammad, Jalan, Arjun, Soleja, Sikander, Zhang, Yayan
- Date
- 2009-12
- Description
-
Sloan Valve manufactures and distributes commercial valves and plumbing fixtures globally. The IPRO team will work to improve the 'procure to...
Show moreSloan Valve manufactures and distributes commercial valves and plumbing fixtures globally. The IPRO team will work to improve the 'procure to pay' process and also assist in the development of a new warehouse management module.
Sponsorship: Sloan Valve Company
Deliverables for IPRO 306: Sloan Valve for the fall 2009 semester.
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- Title
- OPTIMAL DESIGN OF PERMANENT MAGNET SYNCHRONOUS MACHINES BASED ON MAGNETIC FIELD DISTRIBUTION ASSESSMENT AND PERFORMANCE ANALYSIS
- Creator
- Jiang, Yong
- Date
- 2015, 2015-05
- Description
-
The detailed magnetic field distribution of a permanent magnet electric motor is very important for the accurate prediction of performance...
Show moreThe detailed magnetic field distribution of a permanent magnet electric motor is very important for the accurate prediction of performance parameters such as back electromotive force (back-EMF), rotor and stator losses, winding inductances, noise and vibration, torque profiles, etc. Although finite element analysis is a good option for accurately calculating magnetic field distribution in electrical machines, it is typically timeconsuming and does not provide closed form solutions. Alternatively, analytical calculation of magnetic field distribution can be conducted in Fourier series, which is more suitable for a design tool to predict the motor performance. This dissertation presents a novel numerical technique for calculating exact magnetic field distribution in the air gap of a surface mounted permanent magnet machine. This solution can be obtained via a two-dimension analytical solution with Laplacian and quasi-Poisonian equations, assuming that the iron is infinitely permeable and the air gap is slotless. Slot effects can be added in the model by using relative air gap permeance calculated by the conformal transformation of slot geometry. This technique is constructed by multiplying the relative permeance function expressed in an infinite Fourier series with the distribution of magnetic field in the slotless air gap. This method shows a very good alignment with finite element method for a surface mounted permanent magnet machine with radial magnetization. It can also be extended to calculating magnetic field distribution of interior permanent magnet motors including consideration of magnetic saturation, crosssaturation between d-axis and q-axes, affecting both inductances and flux linkages, as well as localized effects due to rotor bridges. Furthermore, this approach can be used to create a closed-form solution, which is the first step towards inverse modeling of electric machines. This is a complete paradigm shift in the design process for electric machines, which can reduce the time taken to design an electric machine, while reducing the active material content to make them power dense with significant reduction in cost. Furthermore, availability of analytical description of the field components will aid in the designer’s ability to distinguish between the control and magnetic design aspects.
Ph.D. in Electrical and Computer Engineering, May 2015
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- Title
- The Tevatron energy scan: Findings & surprises, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
- Creator
- Field, Rick
- Date
- 2013-09-15, 2013-09-15
- Publisher
- IIT Press
- Description
-
At CDF we study charged particle production (pT > 0.5 GeV/c, |η|
Show moreAt CDF we study charged particle production (pT > 0.5 GeV/c, |η| < 0.8) in proton-antiproton collisions at 300 GeV, 900 GeV, and 1.96 TeV. The 300 GeV and 900 GeV data are a result of the “Tevatron Energy Scan” which was performed just before the Tevatron was shut down. We use the direction of the leading charged particle in each event, PTmax, to define three regions of η-φ space; “toward,” “away,” and “transverse.” The “trans- verse” region is further divided into the “transMAX” and “transMIN” con- tributions. The “transMIN” region is very sensitive to the multiple parton interaction component (MPI) of the “underlying event,” while the “trans-DIF” (“transMAX” minus “transMIN”) is very sensitive to the initial and final-state radiation. This CDF analysis together with LHC data provides a detailed study the energy dependence of the various components of the “underlying event” in hadronic collisions.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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- Title
- Coupling of Twin Supersonic Jets of Complex Geometry
- Creator
- Raman, G.
- Date
- 1999-10
- Publisher
- American Inst Aeronaut Astronaut
- Description
-
Fundamental issues about the coupling of twin supersonic jets of complex geometry are examined. It is shown that screech tones from twin...
Show moreFundamental issues about the coupling of twin supersonic jets of complex geometry are examined. It is shown that screech tones from twin rectangular nozzles with double-beveled exit geometries can couple. Unlike coupling of twin rectangular jets of uniform geometry, the coupling here is more intricate because simultaneous multiple frequencies with a different spanwise modal structure are present. The coupling produces two frequencies, one of which is lower than the screech frequency of either jet. Although many coupling modes are kinematically permissible, the twin jets prefer two specific modes, and in some cases these two coupling modes coexist at different frequencies. Despite the geometric complexity we can effectively predict frequencies of tones from both single and twin coupled jets using the waveguide approach. It is hoped that these results and insights will assist those simulating screech for the purpose of tailoring shock-containing complex twin jets that minimize sonic fatigue failure of aircraft structures.
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- Title
- Batch process monitoring and its application to polymerization systems
- Creator
- Undey, C., Ertunc, S., Tatara, E., Teymour, F., Cinar, A.
- Date
- 2004-01
- Publisher
- WILEY-V C H VERLAG GMBH
- Description
-
Slight changes in raw material properties or operating conditions during critical periods of operation of batch and semi-batch polymerization...
Show moreSlight changes in raw material properties or operating conditions during critical periods of operation of batch and semi-batch polymerization reactors may have a strong influence on reaction mechanism and impact final product quality. Online process monitoring, fault detection, fault diagnosis, and product quality prediction in real-time ensure safe reactor operation and warn operators about excursions from normal operation that may lead to deterioration in product properties. Multivariate statistical process monitoring and quality prediction using multiway principal components analysis and multiway partial least squares have been successful in detecting abnormalities in process operation and product quality. When abnormal process operation is detected, fault diagnosis tools are used to determine the source cause of the deviation. Illustrative case studies are presented via simulated polyvinyl acetate polymerization.
Endnote format citation for DOI:10.1002/masy.200450210
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- Title
- Effect of Asymmetric Manipulations in Autocatalytic Networks
- Creator
- Balasubramanian, Sukanya, Cinar, Ali, Teymour, Fouad
- Date
- 2010-06-02
- Publisher
- AMER CHEMICAL SOC
- Description
-
In this paper, we show that heterogeneous networks can be configured and reconfigured to operate in flexible spatial patterns The concept is...
Show moreIn this paper, we show that heterogeneous networks can be configured and reconfigured to operate in flexible spatial patterns The concept is demonstrated by using a square grid of continuous stirred tank reactors with nearest neighbor interactions and hosting multiple cubic autocatalytic species Asymmetry is introduced in the system by allowing for different feed flow rates in the reactors. A heterogeneous system offers expanded phase space, improved stability. and coexistence characteristics The advantages of asymmetry are studied using bifurcation diagrams, continuation studies. and dynamics
Endnote format citation for DOI:10.1021/ie901096v
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- Title
- A Video Annotation and Indexing System (sequence unknown), IPRO 327 - Deliverables: IPRO 327 Final Report F09
- Creator
- Dhagam, Karthik, Donchev, Alexander, Homawoo, Sergio, Litas, Alexander, Orlichenko, Anton, Osswald, Christian, Petsod, Jason, Rawlings, Ori, Shaffer, Joshua, Smith, Antoinette, Yates, Andrew, Yu, Hee Jeoung
- Date
- 2009-12
- Description
-
Much information available on the Web is in video format. The problem with this medium is users cannot comment on particular scenes within the...
Show moreMuch information available on the Web is in video format. The problem with this medium is users cannot comment on particular scenes within the videos and there is no method of searching for specific content within the videos. The team proposes to develop a system that will allow users to make fine-grained comments on scenes within the video and then to use these comments to aid in search within videos.
Deliverables for IPRO 327: A video annotation and indexing system for the fall 2009 semester
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- Title
- Finding Uses for Alternative Fuels in Intermodal Transportation Hubs (sequence unknown), IPRO 307 - Deliverables: IPRO 307 Final Report F09
- Creator
- Balakirev, Konstantin, Beau‐luby, Ryan, Bouikidis, John, Cargill, Matthew, Dziuba, David, Kehoe, Matthew, Slonski, Bryan, Tesfaye, Melat, Wiese, Matthew, Wiseman, Christopher, Zook, Joel
- Date
- 2009-12
- Description
-
Chicago, being the third largest freight hub in the world, needs an efficient movement of goods for the increasing freight shipments.
Sponsorsh...
Show moreChicago, being the third largest freight hub in the world, needs an efficient movement of goods for the increasing freight shipments.
Sponsorship: Mi-Jack
Deliverables for IPRO 307: Finding Uses for Alternative Fuels in Intermodal Transportation Hubs for the fall 2009 semester.
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- Title
- PLS, balanced, and canonical variate realization techniques for identifying VARMA models in state space
- Creator
- Negiz, A., Cinar, A.
- Date
- 1997-10
- Publisher
- ELSEVIER SCIENCE BV
- Description
-
This paper demonstrates the application of PLS regression, balanced realization, and canonical variate (CV) state space modeling techniques in...
Show moreThis paper demonstrates the application of PLS regression, balanced realization, and canonical variate (CV) state space modeling techniques in identifying stationary vector autoregressive moving average (VARMA) type of time series models in state space. An example VARMA process model is used to generate data, carry out modeling activities, and compare the three model development techniques. All realization methods provide equivalent state space models. Balanced realization can not handle singularities in the covariance matrix of past observations while all other methods can accommodate such singularities. Balanced realization and classical PLS do not provide minimal state variables that are orthogonal. 'Orthogonal states' PLS and canonical variate state space realization give orthogonal state variables that provide robust parameter estimates from real data, however the PLS method requires an additional singular value decomposition step.
Endnote format citation
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- Title
- Eco-Life (URBAN REDEVELOPMENT following CATASTROPHE in nanjing, china): Yingqiu Wu_Master project_May 2011++
- Creator
- Wu, Yingqiu
- Date
- 2011-05-04, 2011-05
- Description
-
My project is an urban redevelopment following catastrophe. A catastrophic explosion in 2010 left a portion of Nanjing city destroyed. The...
Show moreMy project is an urban redevelopment following catastrophe. A catastrophic explosion in 2010 left a portion of Nanjing city destroyed. The project proposes a new urban plan to rebuild the neighborhood and restore the community. A powerful explosion at an abandoned plastics factory in Qixia district of Nanjing city has left several people dead and dozens injured. Buildings and vehicles within 100m of the factory destroyed, 3000 citizen got the key of the street and buildings suffered varying degrees of damage in the area 8 miles in circumference. The blast was caused by a leak from a gas pipeline inside the factory, the blast happened after workers dismantling the plant damaged a propylene pipeline. The leaked gas was then ignited when a car engine was started at the scene. There were a community college and several kindergartens in this area, fortunately, it was summer break at that time, no students hurt reported. It is a unique opportunity to develop a plan in an urban context when the prior years of development have been wiped away. The purpose of the project is giving condos return to 3000 people who lost their houses in the explosion and planing mix-used buildings of the community for next 20 years. At present, many old nerghbourhoods in China are being replaced by new ones. In the most cases, the existing urban patternes are erased and a town is built with out any links to what had previouly existed there. My ptoposal is reusing most of the existing tree line streets, river and bridges. The key of this proposal is sustainability, first idea is using existing river to develop a nice wetland park and the second idea is farming gradens.
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- Title
- Planning for Human Implantation of a Cortical Visual Prosthesis (sequence unknown), IPRO 334 - Deliverables: IPRO 334 Project Plan F09
- 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
- DEVELOPMENT OF NANOPARTICLE APPLICATIONS IN CELL IMAGING, BIOASSAY AND REACTIVE OXYGEN SPECIES DETECTION BASED ON SURFACE-ENHANCED RAMAN SPECTROSCOPY
- Creator
- Yiming, Huang
- Date
- 2011-08, 2011-07
- Description
-
After mid-1970, the exploration of surface-enhanced Raman scattering (SERS) has been studied by many research groups. Compared to traditional...
Show moreAfter mid-1970, the exploration of surface-enhanced Raman scattering (SERS) has been studied by many research groups. Compared to traditional Raman spectroscopy, enormous cross section of molecules can be obtained in SERS by placing the molecules within the electromagnetic field present in metal surfaces. This enhancement is due to resonance between the optical field and surface plasmon of the metal substrate. Nanoshells which are composed of a silica core and a thin gold shell can greatly enhance Raman scattering without the need to pre-aggregate the particles, due to their tunable optical property. In our study, we synthesized nanoshells as our SERS substrates for Raman tags. The stability of nanoshells coated with three different self-assembled monolayers containing poly(ethylene glycol) (PEG) molecules has been studied. Probes with Raman active PEG molecules have been delivered and imaged in macrophage cells and MCF7 cells, based on SERS technique. The benefits of this imaging technique we developed here are: 1) it is faster; 2) it requires less preparation; 3) it can provide the information of nanoshells in a semi-quantitative way in vitro. We also developed a rapid and easy-to-execute half-sandwich bioassay for the detection of low volumes (< 2 μL) of antigens on nitrocellulose membrane, based on SERS. Multiple antibodies with MW from 18.2 kDa to 170 kDa were bioconjugated to polymers and grafted to nanoshell surface to detect antigens on the membrane. SERS-based biosensors were tagged with Raman active PEGs for recognition and quantification. Here, the bioassay showed great sensitivity to very low concentration x viii of antigens and multiplexed testing have been successfully conducted on different antigens simultaneously. Moreover, SERS-based novel reactive oxygen species (ROS) sensors were designed by establishing mixed-monolayer consisting of poly(ethylene) glycol thiol (PEGSH) and either 4-nitrobenzenethiol (4-NBT) or 4-mercaptophenol (4-MP) on the surface of nanoshells. By analyzing the changes in the molecular Raman spectrum, we were able to track the production of hydroxyl radicals in low concentrations (~ 10 μM). The sensors have been delivered into the cells and did not show significant oxidative stress to the cells. Therefore, these designed sensors are very promising for tracking ROS produced by cells when they are under oxidative stress.
Ph.D. in Chemistry, July 2011
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