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2009

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Articles 5911 - 5940 of 7616

Full-Text Articles in Physical Sciences and Mathematics

Optical Patterning Of Photopolymerisable Materials, Kevin Trainer, Kevin Wearen, Dimana Nazarova, Izabela Naydenova, Vincent Toal Jan 2009

Optical Patterning Of Photopolymerisable Materials, Kevin Trainer, Kevin Wearen, Dimana Nazarova, Izabela Naydenova, Vincent Toal

Conference Papers

Holographic recording is an effective approach for photopolymer surface patterning. It has been previously utilised in acrylamide-based photopolymers and a spatial frequency limit of 200 l/mm has been observed. We report the successful inscription of submicrometer resolution patterns. The spatial frequency response has been extended to 1550 l/mm by introduction of thermal post recording treatment. Initial results from the optical patterning utilising a spatial light modulation (SLM) reveal that the amplitude of the photoinduced surface relief structures is larger in comparison to the amplitude obtained by holographic recording.

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Optical Properties Of Photopolymerisable Nanocomposites Containing Zeolite Nanoparticles, Izabela Naydenova, Tzvetanka Babeva, Elsa Leite, Nitesh Pandey, Temenujka Yovcheva, Svetlana Mintova, Vincent Toal Jan 2009

Optical Properties Of Photopolymerisable Nanocomposites Containing Zeolite Nanoparticles, Izabela Naydenova, Tzvetanka Babeva, Elsa Leite, Nitesh Pandey, Temenujka Yovcheva, Svetlana Mintova, Vincent Toal

Conference Papers

Acrylamide-based photopolymerisable nanocomposites containing three different types of nanozeolites – Si-MFI, AlPO and BEA, were studied. The influence of the porous nanoparticles on the average refractive index, optical scattering, holographic recording properties and shrinkage were characterised.

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Holographic Recording In Charged Photopolymerisable Nanocomposites, Temenujka Yovcheva, Ivanka Vlaeva, Simeon Sainov, Izabela Naydenova, Vincent Toal, Svetlana Mintova Jan 2009

Holographic Recording In Charged Photopolymerisable Nanocomposites, Temenujka Yovcheva, Ivanka Vlaeva, Simeon Sainov, Izabela Naydenova, Vincent Toal, Svetlana Mintova

Conference Papers

Self – processing photopolymers have a large number of different applications due to their versatile properties as holographic recording materials. A significant effort has been directed towards the development of photopolymers for holographic data storage [1, 2], holographic sensors [3], holographic optical elements [4] and display holograms [5]. The Centre for Industrial and Engineering Optics has been developing acrylamide based photopolymers for the last decade [6-8]. The main parameters requiring improvement in these types of photopolymers are their dynamic range and their mechanical stability during the holographic recording. Recently we have successfully used zeolite nanoparticles as dopants in order to …

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Recent And Emerging Applications Of Holographic Photopolymers And Nanocomposites, Izabela Naydenova, Pavani Kotakonda, Raghavendra Jallapuram, Tsvetanka Babeva, Denis Bade, Suzanne Martin, Vincent Toal, Svetlana Mintova Jan 2009

Recent And Emerging Applications Of Holographic Photopolymers And Nanocomposites, Izabela Naydenova, Pavani Kotakonda, Raghavendra Jallapuram, Tsvetanka Babeva, Denis Bade, Suzanne Martin, Vincent Toal, Svetlana Mintova

Conference Papers

Sensing applications of holograms may be based on effects such as change in the spacing of the recorded fringes in a holographic diffraction grating in the presence of an analyte so that the direction of the diffracted laser light changes, or, in the case of a white light reflection grating, the wavelength of the diffracted light changes. An example is a reflection grating which swells in the presence of atmospheric moisture to indicate relative humidity by a change is the colour of the diffracted light. These devices make use of the photopolymer’s ability to absorb moisture. In a more versatile …

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A Mobile Ecg Monitoring System With Context Collection, Jin Peng Li, Damon Berry, Richard Hayes Jan 2009

A Mobile Ecg Monitoring System With Context Collection, Jin Peng Li, Damon Berry, Richard Hayes

Conference Papers

Preventative health management represents a shift from the traditional approach of reactive treatment-based healthcare towards a proactive wellness-management approach where patients are encouraged to stay healthy with expert support when they need it, at any location and any time. This work represents a step along the road towards proactive, preventative healthcare for cardiac patients. It seeks to develop a smart mobile ECG monitoring system that requests and records context information about what is happening around the subject when an arrhythmia event occurs. Context information about the subject’s activities of daily living will, it is hoped, provide an enriched data set …

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Stepping Off The Stage, Brian Mac Namee, John D. Kelleher Jan 2009

Stepping Off The Stage, Brian Mac Namee, John D. Kelleher

Conference papers

Mixed-reality virtual agents are an attractive solution to the problems associated with human-robot interaction, allowing all the expressiveness of virtual characters to be married with the advantages of a physical artifact which exists in a shared environment with the user. However, common approaches to achieving this restrict the virtual characters appearing on top of, or encompassing the robot. This paper describes the Stepping Off the Stage system in which mixed-reality agents are allowed to step off the robot stage and move to other parts of the environment, offering compelling new interaction possibilities.

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Macular Pigment Levels Increase Following Blue-Light Filtering Intraocular Lens Implantation., James Loughman Jan 2009

Macular Pigment Levels Increase Following Blue-Light Filtering Intraocular Lens Implantation., James Loughman

Other Resources

No abstract provided.

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Shadowing Chaos Via Optimization, Henrik Haakonsen Jan 2009

Shadowing Chaos Via Optimization, Henrik Haakonsen

Mathematics, Statistics, and Computer Science Honors Projects

A prominent idea in the theory of chaos is that of shadowing, which says that, in many cases, the numerical results one sees after accuracy is lost are not total nonsense, but are in fact very close to the exact trajectory for an initial value that is near the one used. Using high-precision computation, I have researched the use of optimization as a way of finding exact shadows for several chaotic systems, such as the quadratic map r x (1 - x) and a billiard problem from the SIAM 100-Digit Challenge.

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Sustainability: Energy & Global Chemistry, Kurt W. Kolasinski Jan 2009

Sustainability: Energy & Global Chemistry, Kurt W. Kolasinski

Chemistry Faculty Publications

No abstract provided.

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Economic Impacts Of Future Biorefineries In The State Of Arkansas: An Input-Output Analysis, Sayeed R. Mehmood, M. H. Pelkki Jan 2009

Economic Impacts Of Future Biorefineries In The State Of Arkansas: An Input-Output Analysis, Sayeed R. Mehmood, M. H. Pelkki

Journal of the Arkansas Academy of Science

No abstract provided.

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Melting Of Major Glaciers In The Western Himalayas: Evidence Of Climatic Changes From Long Term Msu Derived Tropospheric Temperature Trend (1979-2008), Anup K. Prasad, Keun-Hang Susan Yang, Hesham El-Askary, Menas Kafatos Jan 2009

Melting Of Major Glaciers In The Western Himalayas: Evidence Of Climatic Changes From Long Term Msu Derived Tropospheric Temperature Trend (1979-2008), Anup K. Prasad, Keun-Hang Susan Yang, Hesham El-Askary, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

Global warming or the increase of the surface and atmospheric temperatures of the Earth, is increasingly discernible in the polar, sub-polar and major land glacial areas. The Himalayan and Tibetan Plateau Glaciers, which are the largest glaciers outside of the Polar regions, are showing a large-scale decrease of snow cover and an extensive glacial retreat. These glaciers such as Siachen and Gangotri are a major water resource for Asia as they feed major rivers such as the Indus, Ganga and Brahmaputra. Due to scarcity of ground measuring stations, the long-term observations of atmospheric temperatures acquired from the Microwave Sounding Unit …

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The Land Use Planning, Water Resources And Climate Change Adaptation Connection: Challenges And Opportunities, Bobbie Klein, Douglas S. Kenney Jan 2009

The Land Use Planning, Water Resources And Climate Change Adaptation Connection: Challenges And Opportunities, Bobbie Klein, Douglas S. Kenney

Books, Reports, and Studies

[15] p. ; 28 cm

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A Generic Approach To Computer-Based Clinical Practice Guideling Management Using The Eca Rule Paradigm And Active Databases, Bing Wu, Kudakwashe Dube Jan 2009

A Generic Approach To Computer-Based Clinical Practice Guideling Management Using The Eca Rule Paradigm And Active Databases, Bing Wu, Kudakwashe Dube

Articles

The increasing demand for reduced cost and improved quality of service in healthcare has prompted the call for better management of medical knowledge. The main emphasis has been on knowledge that is acquired through experience and medical research and then formalised into Clinical Practice Guidelines (CPGs). This paper presents a generic approach to CPG information and knowledge management that uses the Event-Condition-Action (ECA) rule paradigm and active databases within a unified management framework. The paper focuses on an approach for facilitating the use and management of CPGs by clinicians through delivering the CPGs at the point-of-care by a computerised mechanism.

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The Good, The Bad And The Incorrectly Classified: Profiling Cases For Case-Base Editing, Sarah Jane Delany Jan 2009

The Good, The Bad And The Incorrectly Classified: Profiling Cases For Case-Base Editing, Sarah Jane Delany

Conference papers

Case-based approaches to classification, as instance-based learning techniques, have a particular reliance on training examples that other supervised learning techniques do not have. In this paper we present the RDCL case profiling technique that categorises each case in a case-base based on its classification by the case-base, the benefit it has and/or the damage it causes by its inclusion in the case-base. We show how these case profiles can identify the cases that should be removed from a case-base in order to improve generalisation accuracy and we show what aspects of existing noise reduction algorithms contribute to good performance and …

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Algorithm For The Analysis Of Tryptophan Flourescence Spectra And Their Correlation With Protein Structural Parameters, John Hixon, Yana K. Reshetnyak Jan 2009

Algorithm For The Analysis Of Tryptophan Flourescence Spectra And Their Correlation With Protein Structural Parameters, John Hixon, Yana K. Reshetnyak

Physics Faculty Publications

The fluorescence properties of tryptophan residues are sensitive to the microenvironment of fluorophores in proteins. Therefore, fluorescence characteristics are widely used to study structural transitions in proteins. However, the decoding of the structural information from spectroscopic data is challenging. Here we present a review of approaches developed for the decomposition of multi-component protein tryptophan fluorescence spectra and correlation of these spectral parameters with protein structural properties.

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Dependence Of Domain Wall Structure For Low Field Injection Into Magnetic Nanowires, Andrew Kunz, Sarah C. Reiff Jan 2009

Dependence Of Domain Wall Structure For Low Field Injection Into Magnetic Nanowires, Andrew Kunz, Sarah C. Reiff

Physics Faculty Research and Publications

Micromagnetic simulation is used to model the injection of a domain wall into a magnetic nanowire with field strengths less than the so-called Walker field. This ensures fast, reliable motion of the wall. When the wire is located at the edge of a small injecting disk, a bias field used to control the orientation of the domain wall can reduce the pinning potential of the structure. The low field injection is explained by a simple model, which relies on the topological nature of a domain wall. The technique can quickly inject multiple domain walls with a known magnetic structure.

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Accurate Analysis Of Tumor Margins Using A Fluorescent Ph Low Insertion Peptide (Phlip), James Segala, Donald M. Engelman, Yana K. Reshetnyak, Oleg A. Andreev Jan 2009

Accurate Analysis Of Tumor Margins Using A Fluorescent Ph Low Insertion Peptide (Phlip), James Segala, Donald M. Engelman, Yana K. Reshetnyak, Oleg A. Andreev

Physics Faculty Publications

The recurrence of certain cancers remains quite high due to either incomplete surgical removal of the primary tumor or the presence of small metastases that are invisible to the surgeon. Near infrared (NIR) fluorescence imaging might improve surgical outcomes by providing sensitive, specific, and real-time visualization of normal and diseased tissues if agents can be found that discriminate between normal and diseased tissue and define tumor margins. We have developed a new approach for revealing tumor borders by using NIR fluorescently labeled pH Low Insertion Peptide (pHLIP) and have created a computational program for the quantitative assessment of tumor boundaries. …

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Nike Considered: Getting Traction On Sustainability, Christopher Lyddy, Rebecca Henderson, Richard M. Locke, Cate Reavis Jan 2009

Nike Considered: Getting Traction On Sustainability, Christopher Lyddy, Rebecca Henderson, Richard M. Locke, Cate Reavis

School of Business Faculty Publications

No abstract provided.

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The Journal Of Undergraduate Research: Volume 07 Jan 2009

The Journal Of Undergraduate Research: Volume 07

The Journal of Undergraduate Research

This is the complete issue of the South Dakota State University Journal of Undergraduate Research, Volume 7.

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Observational Validation Of The Compensating Mass Flux Through The Shell Around Cumulus Clouds, Thijs Heus, C. Freek J. Pols, Harmen J.J. Jonker, Harry E.A. Van Den Akker, Donald H. Lenschow Jan 2009

Observational Validation Of The Compensating Mass Flux Through The Shell Around Cumulus Clouds, Thijs Heus, C. Freek J. Pols, Harmen J.J. Jonker, Harry E.A. Van Den Akker, Donald H. Lenschow

Physics Faculty Publications

The existence of a subsiding shell around cumulus clouds has been observed before in several aircraft measurement campaigns. Recent results from large-eddy simulations (LES) showed that the downward mass flux through the shell compensates for a significant fraction of the upward mass flux through the cloud. In this study, aeroplane measurements from the Rain In Cumulus over the Ocean (RICO) field campaign are used to verify the existence of this compensating mass flux. Just as in the LES results, the in-shell downward mass flux is found to be significant. However, a few differences were found in comparison with the LES …

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Error Control In Wireless Sensor Networks: A Cross Layer Analysis, Mehmet C. Vuran, Ian F. Akyildiz Jan 2009

Error Control In Wireless Sensor Networks: A Cross Layer Analysis, Mehmet C. Vuran, Ian F. Akyildiz

School of Computing: Faculty Publications

Error control is of significant importance for Wireless Sensor Networks (WSNs) because of their severe energy constraints and the low power communication requirements. In this paper, a cross-layer methodology for the analysis of error control schemes in WSNs is presented such that the effects of multi-hop routing and the broadcast nature of the wireless channel are investigated. More specifically, the cross-layer effects of routing, medium access, and physical layers are considered. This analysis enables a comprehensive comparison of forward error correction (FEC) codes, automatic repeat request (ARQ), and hybrid ARQ schemes in WSNs. The validation results show that the developed …

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Smart Templates For Peak Pattern Matching With Comprehensive Two-Dimensional Liquid Chromatography, Stephen E. Reichenbach, Peter W. Carr, Dwight R. Stoll, Qingping Tao Jan 2009

Smart Templates For Peak Pattern Matching With Comprehensive Two-Dimensional Liquid Chromatography, Stephen E. Reichenbach, Peter W. Carr, Dwight R. Stoll, Qingping Tao

School of Computing: Faculty Publications

Comprehensive two-dimensional liquid chromatography (LC × LC) generates information-rich but complex peak patterns that require automated processing for rapid chemical identification and classification. This paper describes a powerful approach and specific methods for peak pattern matching to identify and classify constituent peaks in data from LC × LC and other multidimensional chemical separations. The approach records a prototypical pattern of peaks with retention times and associated metadata, such as chemical identities and classes, in a template. Then, the template pattern is matched to the detected peaks in subsequent data and the metadata are copied from the template to identify and …

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Report On Wintering Western Snowy Plovers At Coos Bay North Spit And Impacts To Plovers From The North Jetty Repair Project, Winter 2009, David J. Lauten, Kathleen J. Castelein, Eleanor P. Gaines Jan 2009

Report On Wintering Western Snowy Plovers At Coos Bay North Spit And Impacts To Plovers From The North Jetty Repair Project, Winter 2009, David J. Lauten, Kathleen J. Castelein, Eleanor P. Gaines

Institute for Natural Resources Publications

The Western Snowy Plover (Charadrius alexandrinus nivosus) breeds along the coast of the Pacific Ocean in California, Oregon, and Washington and at alkaline lakes in the interior of the western United States (Page et al. 1991). Loss of habitat, predation pressures, and disturbance have caused the decline of the coastal population of Snowy Plovers and led to the listing of the Pacific Coast Population of Western Snowy Plovers as Threatened on March 5, 1993 (U.S. Fish and Wildlife Service 1993). Oregon Western Snowy Plovers are known to winter along the coast of Oregon as well as migrate to …

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The Hidden Injuries Of Overloading 'Adt, Duane Buck, David J. Stucki Jan 2009

The Hidden Injuries Of Overloading 'Adt, Duane Buck, David J. Stucki

Mathematics Faculty Scholarship

The most commonly stated definition of abstract data type (ADT) is that it is a domain of values and the operations over that domain. So, for example, a language's built-in types, like int are seen to be ADTs. It is our opinion that a pure interpretation of this definition yields a semantics in which using an ADT is the same as using built-in types: the operations are side effect free and there is no concern over alias, shallow copy or synchronization problems. Unfortunately, the term abstract data type has over time been associated with at least three distinct meanings, and …

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Reliability Goodness Of Fit For Oil Spills In The Gulf Of Mexico, William V. Harper, Thomas R. James, Ted G. Eschenbach Jan 2009

Reliability Goodness Of Fit For Oil Spills In The Gulf Of Mexico, William V. Harper, Thomas R. James, Ted G. Eschenbach

Mathematics Faculty Scholarship

Eschenbach and Harper (2006) analyzed offshore oil spills in the Gulf of Mexico with extensions to the northern seas of Alaska. This involved multiple methods including assessing what statistical distribution adequately fits the data. Empirical distribution function (EDF) statistical procedures are powerful goodness of fit tests and also provide for good visual assessments. The most powerful of the current EDF methods is the Anderson-Darling test. This paper focuses on the Anderson-Darling EDF goodness of fit procedure for both the two and three parameter Weibull distribution that is often used in reliability analysis. Excel VBA code has been developed to compute …

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Tailoring Local Conductivity By The Formation Of Ag Nanoclusters In Sio2 Xerogel Films, Ricky Caperton Jan 2009

Tailoring Local Conductivity By The Formation Of Ag Nanoclusters In Sio2 Xerogel Films, Ricky Caperton

Theses and Dissertations

Porous silicon dioxide thin films were produced via dip-coating and doped with Ag+ by adding AgNO3 to the dipping solution. Nanoparticles were formed within the pores of these films by UV exposure. Nanoparticle formation was confirmed by UV-visible spectroscopy and Transmission Electron Microscopy (TEM). Conductive Atomic Force Microscopy (CAFM) showed that the conductivity of the films decreased upon exposure to UV. This decrease in the conductivity is most likely due to the clustering of charge carriers. Initially, Ag+ ions are attached to negatively charged pore walls in a dense packing network. Upon UV exposure (125 mW @ 266 nm), the …

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Noncovalent Interaction Of Platinum Planar Amine Compounds With Tryptophan: A Strategy To Interfere With P53-Mdm2 Interactions And Targeting Retroviral Zn Finger-Dna Interaction (Hiv Ncp7), Aaron Bate Jan 2009

Noncovalent Interaction Of Platinum Planar Amine Compounds With Tryptophan: A Strategy To Interfere With P53-Mdm2 Interactions And Targeting Retroviral Zn Finger-Dna Interaction (Hiv Ncp7), Aaron Bate

Theses and Dissertations

Non-covalent interactions involving π-π stacking play an essential role in self-assembly and molecular recognition processes such as protein folding and DNA/RNA-protein selective recognition. The knowledge gained from these studies could provide insight into possible site recognition complexes, inhibiting or mimicking protein-protein or protein-DNA interactions. Based on molecular modeling as well as HOMO and LUMO energies, several chromophores were selected with a variety of ∆ε values (∆ε= |εHOMO,NAcTrp – εLUMO,chromophores|), high and low, to establish a correlating trend with the modeling and experimental data. The corresponding Pt(dien) compounds were synthesized and their ability to stack to N-acetyl tryptophan was evaluated by …

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Generation Of Novel Pikromycin Antibiotic Products Through Mutasynthesis, Shuchi Gupta, Venkatraman Lakshmanan, Beom Seok Kim, Robert Fecik, Kevin A. Reynolds Jan 2009

Generation Of Novel Pikromycin Antibiotic Products Through Mutasynthesis, Shuchi Gupta, Venkatraman Lakshmanan, Beom Seok Kim, Robert Fecik, Kevin A. Reynolds

Chemistry Faculty Publications and Presentations

Mutasynthesis in pikromycin PKS: The amenability of pikromycin polyketide synthase to mutational biosynthesis has been demonstrated. A natural triketide and its analogues, activated as N-acetyl-cysteamine thioesters, were synthesized and fed to a pikAI-deleted strain; this led to the production of new antibiotics. A vinyl analogue was found to have better antibacterial activity than pikromycin.

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Optimising The Synthesis And Red–Green–Blue Emission Of A Simple Organic Dye, Martha Sibrian-Vazquez, Robert M. Strongin Jan 2009

Optimising The Synthesis And Red–Green–Blue Emission Of A Simple Organic Dye, Martha Sibrian-Vazquez, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Synthetic dyes have been widely used in supramolecular chemistry not only to probe fundamental chemical interactions but also as components of functional materials. Most current efforts in this regard are directed at designing new host systems for the dyes. Herein we report on the study of a versatile new organic fluorophore. We describe a synthesis which affords improved yields in a convenient one pot procedure. Moreover, a simple method for predicting and controlling the dye’s responses to external stimuli affords a potentially practical method for achieving red–green–blue and concomitant white light generation.

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A Lab To Stemulate Undergraduate Students Into Science, Technology, Engineering And Mathematics Majors, Nicole Lynn Speelman Jan 2009

A Lab To Stemulate Undergraduate Students Into Science, Technology, Engineering And Mathematics Majors, Nicole Lynn Speelman

Browse all Theses and Dissertations

The central focus is the development and implementation of a research/lab module for first year chemistry courses. Electrochemical techniques are utilized to study oxidation and reduction reactions of neurotransmitters with a poly(2,2'-Bithiophene) modified electrode. The goal is to excite students about chemistry and encourage them to continue studies in Science, Technology, Engineering, and Mathematics (STEM) during their undergraduate education. The lab module was created for Project REEL (Research Experiences to Enhance Learning) and will be illustrated with results typically obtained by students. The experiment is inquiry-based, which includes challenging questions students have to do collaboration and research to answer, as …

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