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An Ethnobotanical, Ecological And Lc-Ms-Based Chemometric Investigation Of Phaleria Nisidai, A Traditional Adaptogen Containing Diterpene Esters From Palau, Micronesia, Daniel Kulakowski Feb 2014

An Ethnobotanical, Ecological And Lc-Ms-Based Chemometric Investigation Of Phaleria Nisidai, A Traditional Adaptogen Containing Diterpene Esters From Palau, Micronesia, Daniel Kulakowski

Dissertations, Theses, and Capstone Projects

An ethnobotanical, ecological and LC-MS-based chemometric investigation of Phaleria nisidai, a traditional adaptogen containing diterpene esters from Palau, Micronesia

Palau is a country with a rich heritage of traditional medicine still being practiced. One of the most popular and respected remedies in Palau is a tea made from fresh leaves of Phaleria nisidai Kaneh. (Thymelaeaceae). Interviews conducted to determine the use of this plant revealed that it is employed non-specifically to treat a variety of general health concerns. Its use as a prophylactic to keep away sickness, as a 'system cleaner', as well as for strength and energy indicate …


Intelligent Nano/Microgels For Cell Scaffold And Drug Delivery System, Jing Shen Feb 2014

Intelligent Nano/Microgels For Cell Scaffold And Drug Delivery System, Jing Shen

Dissertations, Theses, and Capstone Projects

Stimulus-responsive polymer microgels swell and shrink reversibly upon exposure to various environmental stimuli such as change in pH, temperature, ionic strength or magnetic fields. Therefore, they become ideal candidates for biomaterial applications. For this work, we focus on the several intelligent microgels and their application on two areas: the cell scaffold and the drug delivery system.

As for the cell scaffold, it can be realized by colloidal supra-structure microgels, which constructed by the thermo-driven gelation of the colloidal dispersion of poly(N-isopropylacrylamide-co-acrylamide) poly(NIPAM-co-AAm) microgels (Chapter 3). Such microgels exhibit a reversible and continuous volume transition in water with volume phase transition …


Paper-Based Standard Addition Assays, Cory A. Chaplan, Haydn T. Mitchell, Andres W. Martinez Jan 2014

Paper-Based Standard Addition Assays, Cory A. Chaplan, Haydn T. Mitchell, Andres W. Martinez

Chemistry and Biochemistry

Standard addition assays conducted on paper-based microfluidic devices are introduced as an alternative to external standards for calibrating quantitative tests. To demonstrate this technique, a colorimetric, paper-based, standard addition assay was optimized for the determination of glucose concentrations in the range of 0 to 5 mM. Comparable results were obtained from the assay via digital image colorimetry under three different lighting conditions.


Electronic Control Of The Photocycloaddition Of Silyl Tethered Alkenes, Kari Cowdell, Dr. Steven A. Fleming Jan 2014

Electronic Control Of The Photocycloaddition Of Silyl Tethered Alkenes, Kari Cowdell, Dr. Steven A. Fleming

Journal of Undergraduate Research

Solar energy is a major reason for the study of photochemistry. Photochemistry is the investigation of the interaction of organic compounds with light. The ability of plants and bacteria to harness the sun’s energy is an example of photochemistry. One area of photochemical research is the synthesis of cyclobutane rings which are found in plant essential oils and animal pheromones. Anticancer drugs such as taxol also have four member rings in their structures. Biological systems are unique in their ability to produce cyclobutane systems with specific stereochemistry that current methods of synthesis require great effort to acquire. It has been …


Isolation, Purification, And Characterization Of Biologically Active Compounds From Endophytic Fungi, Trisha L. Anderson, Dr. Noel L. Owen Jan 2014

Isolation, Purification, And Characterization Of Biologically Active Compounds From Endophytic Fungi, Trisha L. Anderson, Dr. Noel L. Owen

Journal of Undergraduate Research

This project focused on endophytic fungi, fungi that live inside of plants without causing disease, as a source of compounds that may be useful in treating human disease. Endophytic fungi were chosen both because their relationship with the plants in which they live indicates that they provide some benefit to the plant and because they have a more specific relationship with a plant host, making acquisition of future samples of the same fungus more feasible. In addition, these fungal species have been less studied than many other aspects of natural products research. This research centered on the isolation of novel …


Elements Regulating Excision Of Chicken Cyclooxygenase-2 Intron 1, Nathan Evanson, Dr. Daniel L. Simmons Jan 2014

Elements Regulating Excision Of Chicken Cyclooxygenase-2 Intron 1, Nathan Evanson, Dr. Daniel L. Simmons

Journal of Undergraduate Research

Cyclooxygenases (COXs) are enzymes that are responsible for the production of a potent class of biological signaling molecules called prostaglandins. Prostaglandins are involved in responses such as inflammation, contraction of smooth muscle, and regulation of water balance in the kidney. They are also found in greatly elevated amounts in some types of cancer. This elevation in prostaglandins is the result of increased production of the form of COX known as COX-2. Because COX-2 may play a role in the development of cancer, an understanding of how COX-2 is regulated is important in the understanding of cancer and may give insights …


Thermochemical Properties Of C3 To C5 Unsaturated Carbonyl Alkenes: Enthalpies Of Formation, Entropy, Heat Capacity, Bond Enthalpy, Ruiqi Jian Jan 2014

Thermochemical Properties Of C3 To C5 Unsaturated Carbonyl Alkenes: Enthalpies Of Formation, Entropy, Heat Capacity, Bond Enthalpy, Ruiqi Jian

Theses

α,β and α-γ unsaturated carbonyl compounds are important classes of carbonyl compounds with the general structure R-(O=C)-Cα=Cβ-R’ and R-(O=Cγ)-Cβ-Cα=Cβ-R’. These compounds are utilized in industry and are also produced as intermediates of hydrocarbon oxidation in chemistry of the atmosphere and in combustion. These unsaturated carbonyls are common environmental pollutants, are frequently associated with adverse effects, and are considered to play an important role in human cancer. Their stability, thermochemical properties are important to understanding their reaction paths in atmospheric, combustion and bio related environments. Enthalpy, entropy, and heat capacity of unsaturated alkene molecules, and radicals corresponding to hydrogen atom …


Detection And Assay Of Riboflavin (Vitamin B2) Utilizing Uv/Vis Spectrophotometer And Citric Acid Buffer, Ronald Bartzatt, Michelle Lee Follis Jan 2014

Detection And Assay Of Riboflavin (Vitamin B2) Utilizing Uv/Vis Spectrophotometer And Citric Acid Buffer, Ronald Bartzatt, Michelle Lee Follis

Chemistry Faculty Publications

Aims: Riboflavin is a B vitamin that is required for a wide variety of cellular processes. The absorbance spectrum of riboflavin was determined at different pH utilizing several buffers. The buffer at pH demonstrating table absorbance peaks with high numerical values of molar absorptivity is followed by accurate and sensitive assay of riboflavin by spectrophotometer. Study Design: The absorbance spectrum of riboflavin is determined in an aqueous buffer at various pH values. After identifying the absorbance peaks providing maximal molar absorptivity the assay of riboflavin in the identical buffer was undertaken. Place and Duration of Study: Department of Chemistry, Durham …


Effects Of Protein Ratio And Concentration On Nitrogenase Catalyzed Substrate Reduction, Kyrsten Ann Crawford, Dr. Gerald D. Watt Jan 2014

Effects Of Protein Ratio And Concentration On Nitrogenase Catalyzed Substrate Reduction, Kyrsten Ann Crawford, Dr. Gerald D. Watt

Journal of Undergraduate Research

Although the earth’s atmosphere is approximately 80% nitrogen (N2) gas, this form of nitrogen is inert and must be reduced and “fixed” into a useable form of nitrogen through the process of nitrogen fixation. Nitrogen fixation is an important biological process in the earth’s nitrogen cycle because it provides nutrient nitrogen for plants and animals. The enzyme responsible for conducting nitrogen fixation is nitrogenase, which is found only in certain diazotrophic microorganisms. Nitrogenase is also capable of reducing protons (H+) and small substrates that have a terminal triple bond, such as acetylene (C2H2 …


Polymeric Monolithic Stationary Phases For Capillary Reversed-Phase Liquid Chromatography Of Small Molecules, Kun Liu Jan 2014

Polymeric Monolithic Stationary Phases For Capillary Reversed-Phase Liquid Chromatography Of Small Molecules, Kun Liu

Theses and Dissertations

Highly cross-linked monoliths prepared from single cross-linking monomers were found to increase surface area and stability. Therefore, seven cross-linking monomers, i.e., 1,3-butanediol dimethacrylate (1,3-BDDMA), 1,4-butanediol dimethacrylate (1,4-BDDMA), neopentyl glycol dimethacrylate (NPGDMA), 1,5-pentanediol dimethacrylate (1,5-PDDMA), 1,6-hexanediol dimethacrylate (1,6-HDDMA), 1,10-decanediol dimethacrylate (1,10-DDDMA), and 1,12-dodecanediol dimethacrylate (1,12-DoDDMA), were used to synthesize highly cross-linked monolithic columns in 75-µm i.d. capillaries by one-step UV-initiated polymerization using dodecanol and methanol as porogens for reversed-phase liquid chromatography (RPLC) of small molecules. Selection of porogen type and concentration was investigated in detail. Isocratic elution of alkylbenzenes at a flow rate of 300 nL/min was conducted for all of …


Regio- And Stereoselective Photochemical [2+2] Cycloaddition Between 4-Hydroxycoumarin And Alkenes, Scott Henneman, Dr. Steven A. Fleming Jan 2014

Regio- And Stereoselective Photochemical [2+2] Cycloaddition Between 4-Hydroxycoumarin And Alkenes, Scott Henneman, Dr. Steven A. Fleming

Journal of Undergraduate Research

Recent photochemical research has proven helpful in understanding the regio- and stereoselective mechanism of four-member ring formation. When compounds cycloadd— combine either inter- or intramolecularly to form rings—a broad assortment of isomers are generally formed. However, the regio- and stereoselectivity of the cycloaddition process—the tendency of the compounds to combine in specific ways, i.e. the preference for one product over another—can be greatly enhanced through the utilization of a tether group. This tether group can be anything used to control the reacting molecular components involved in a cycloaddition towards combination in a specific orientation. The regio- and stereoselectivity of the …


Potential Inhibitors Of Hiv Integrase, Daniel A. Gubler, Dr. Matt A. Peterson Jan 2014

Potential Inhibitors Of Hiv Integrase, Daniel A. Gubler, Dr. Matt A. Peterson

Journal of Undergraduate Research

The purpose of my research is to synthesize a new class of enediynes that mimic linbenzoadenosine derivatives and have potential for inhibiting HIV integrase. This new class of enediynes is shown in Figure 1. Upon synthesis we will evaluate the biological activity of these compounds.


Fabrication Of Cds Nanoparticle Coated Jasmonate Conjugates And Their Interactions With Mammalian Cells, Nazmul Sarker Fcrh '13, Stacey Barnaby Fcrh '11, Ipsita Bannerjee Jan 2014

Fabrication Of Cds Nanoparticle Coated Jasmonate Conjugates And Their Interactions With Mammalian Cells, Nazmul Sarker Fcrh '13, Stacey Barnaby Fcrh '11, Ipsita Bannerjee

The Fordham Undergraduate Research Journal

In this work, we have grown CdS nanoparticles on jasmonate nanoassemblies biomimetically and examined their interactions with mammalian cells. In general, plants naturally secrete the phytohormone jasmonic acid during development and in response to biotic and abiotic stress as a defense mechanism (Traw and Bergelson 2003; Sembdner and Parthier 1993). We have developed a new class of nanomaterials by utilizing nanoassemblies of the plant phytohormone jasmonic acid (JA) as templates for the growth of quantum dots, which may have potential applications as sensors and may potentially be utilized for bioimaging applications.


Br[O/]Nsted Acid Catalyzed Asymmetric Allylation And Propargylation Of Aldehydes, Pankaj Jain Jan 2014

Br[O/]Nsted Acid Catalyzed Asymmetric Allylation And Propargylation Of Aldehydes, Pankaj Jain

USF Tampa Graduate Theses and Dissertations

Carbonyl allylation and propargylation reactions have been an important tool for the stereocontrolled formation of carbon-carbon bonds for synthetic chemists. The chiral homoallylic and homopropargylic alcohols obtained from these reactions serve as versatile intermediates for the synthesis of natural and pharmaceutical products. Over the past three decades and continuing on, various synthetic groups around the globe have directed their research towards the efficient synthesis of these chiral moieties. In spite extensive research, asymmetric allylation and propargylation reactions remain an enduring challenge in organic chemistry.

Chapter 1 of this thesis describes the first phosphoric acid catalyzed asymmetric allylboration of aldehydes. We …


Synthesis And Characterization Of New Gd3+-Containing Complexes As Potential Targeted Contrast Agents For Magnetic Resonance Imaging, Sashiprabha Manjari Vithanarachchi Jan 2014

Synthesis And Characterization Of New Gd3+-Containing Complexes As Potential Targeted Contrast Agents For Magnetic Resonance Imaging, Sashiprabha Manjari Vithanarachchi

Wayne State University Dissertations

The focus of the research described in this thesis is the study of chemistry relevant to target-specific contrast agents for magnetic resonance imaging (MRI). MRI is a widely used technique in diagnostic medicine and biomedical research to obtain anatomical and physiological details of soft tissues. Contrast agents are used to enhance the contrast of MR images by causing changes to the chemical environment of water molecules. Clinically approved GdIII-containing contrast agents for MRI are non-specific, and consequently, have limited utility. Target-specific contrast agents represent one way to circumvent this limitation. In the research described in this thesis, myelin and Β-amyloid …


The Cytotoxic Effect Of 2-Acylated-1,4-Naphthohydroquinones On Leukemia/Lymphoma Cells, Diego A. Pedroza, Fernando De Leon, Armando Varela-Ramirez, Carolina Lerma, Renato J. Aguilera, Shizue Mito Jan 2014

The Cytotoxic Effect Of 2-Acylated-1,4-Naphthohydroquinones On Leukemia/Lymphoma Cells, Diego A. Pedroza, Fernando De Leon, Armando Varela-Ramirez, Carolina Lerma, Renato J. Aguilera, Shizue Mito

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Here, we tested seven 2-acylated-1,4-hydronaphthoquinones for their cytotoxic effects on a panel of cancer lymphoma/leukemia cells and compared to a non-cancer origin cell line. Several naphthohydroquinones exhibited selective cytotoxic effects on lymphoma/leukemia cells with lowest activity on non-cancer cells. The mode of cell death induced by an acylated naphthohydroquinone, which has a long alkyl chain, was found to be via apoptosis. Furthermore, the naphthohydroquinone provoked mitochondria depolarization and activation of its downstream effector, caspase-3, thus implicating the intrinsic apoptotic pathway as its mechanism to exert cell death.


Bsa–Boronic Acid Conjugate As Lectin Mimetics, Satya Nandana Narla, Poornima Pinnamaneni, Huan Nie, Yu Li, Xue-Long Sun Jan 2014

Bsa–Boronic Acid Conjugate As Lectin Mimetics, Satya Nandana Narla, Poornima Pinnamaneni, Huan Nie, Yu Li, Xue-Long Sun

Chemistry Faculty Publications

We report bovine serum albumin (BSA)–boronic acid (BA) conjugates as lectin mimetics and their glyco-capturing capacity. The BSA–BA conjugates were synthesized by amidation of carboxylic acid groups in BSA with aminophenyl boronic acid in the presence of EDC, and were characterized by Alizarin Red S (ARS) assay and SDS–PAGE gel. The BSA–BA conjugates were immobilized onto maleimide-functionalized silica beads and their sugar capturing capacity and specificity were confirmed by ARS displacement assay. Further, surface plasmon resonance (SPR) analysis of the glyco-capturing activity of the BSA–BA conjugates was conducted by immobilizing BSA–BA onto SPR gold chip. Overall, we demonstrated a BSA–BA-based …


Investigation And Characterization Of Pt-Modified Au Catalysts And Polymer Composites By Electrochemistry, Raman And Surface Enhanced Raman Spectroscopy (Sers), Ranjani Muralidharan Jan 2014

Investigation And Characterization Of Pt-Modified Au Catalysts And Polymer Composites By Electrochemistry, Raman And Surface Enhanced Raman Spectroscopy (Sers), Ranjani Muralidharan

USF Tampa Graduate Theses and Dissertations

This dissertation thesis consists of six chapters. The main focus of this study is the need for understanding the reaction mechanism and intermediates formed on Pt-modified Au surface as anode catalysts in the formic acid fuel cells. Chapter 1 gives an introduction to formic acid and methanol fuel cells, an overview of the current catalysts employed at the anode of the fuel cells, specifically the Pt-modified Au electrodes as potential catalysts and the different deposition methods for preparing this catalytic surface. Information about different electrochemical methods used like cyclic voltammetry and potential step method along with other characterization methods and …


Collisional Dynamic Elements Of The Pyrazine - N2o System:Middle And Low J States, La Moyne Tyler Mix Jan 2014

Collisional Dynamic Elements Of The Pyrazine - N2o System:Middle And Low J States, La Moyne Tyler Mix

Theses and Dissertations

Unimolecular reactions based on the Lindemann - Hinchelwood mechanism are important to understanding combustion and atmospheric processes. The main feature of this mechanism is the energy transfer probability distribution function, P(E',E). We have chosen to study P(E',E) through gas phase collisional dynamics probed with IR transient absorption spectroscopy. Post-collision absorption line widths for the pyrazine-N2O system are used to calculate lab frame translational temperatures. The translational temperatures reveal that collisions with large rotational energy transfer also transfer large amounts of translational energy. For J states >47 the relationship is linear indicating a constant impact parameter. Line widths for J=47 through …


Expression And Characterization Of The Novel Oxidase Virh-Ox, John Dronzek Jan 2014

Expression And Characterization Of The Novel Oxidase Virh-Ox, John Dronzek

Chemistry Honors Papers

No abstract provided.


Developing Transfer Skills In A Biochemistry Class, Jeong V. Choe Jan 2014

Developing Transfer Skills In A Biochemistry Class, Jeong V. Choe

Faculty Publications & Research

Students seem to struggle with transferring prior knowledge if the new problem they are given is in a different form from the way they learned the material. The process of transfer can be identified by four components: 1) recognizing the similarity between the old and new contexts; 2) identifying the potential of a certain skill or concept that has worked in the past, to give solutions to new problematic situations; 3) mental testing of the application of the potential solution; and 4) an attempt to apply the skill or concept to a new context (Georghiades 2000). These four components are …


Effects Of Oxidation On Protein-Nanoparticle Interactions, Valdez R. Rahming, Md. Abul Fazal Jan 2014

Effects Of Oxidation On Protein-Nanoparticle Interactions, Valdez R. Rahming, Md. Abul Fazal

Chemistry Faculty Publications

Aims: Upon entrance into the blood stream most nanoparticles bind to an array of proteins forming a “protein corona”. Fibrinogen is the second most abundant blood protein and has been reported to bind to a variety of nanoparticles including metal oxides, polymeric nanoparticles and carbon nanotubes.
Study Design: Study the effects of oxidation on the binding interactions between human serum fibrinogen and magnetic iron (III) oxide nanoparticles.
Place and Duration of Study: Department of Chemistry, College of St. Benedict, 37 South College Avenue, St. Joseph, MN 56374, U.S.A., between June 2011 and May 2012.
Methodology: Spectroscopic techniques (UV-Vis, IR, fluorescence, …


Simultaneous High-Performance Liquid Chromatography-Tandem Mass Spectrometry (Hplc-Ms-Ms) Analysis Of Cyanide And Thiocyanate From Swine Plasma, Raj K. Bhandari, Erica Manandhar, Robert P. Oda, Gary A. Rockwood, Brian A. Logue Jan 2014

Simultaneous High-Performance Liquid Chromatography-Tandem Mass Spectrometry (Hplc-Ms-Ms) Analysis Of Cyanide And Thiocyanate From Swine Plasma, Raj K. Bhandari, Erica Manandhar, Robert P. Oda, Gary A. Rockwood, Brian A. Logue

Chemistry and Biochemistry Faculty Publications

An analytical procedure for the simultaneous determination of cyanide and thiocyanate in swine plasma was developed and validated. Cyanide and thiocyanate were simultaneously analyzed by high-performance liquid chromatography tandem mass spectrometry in negative ionization mode after rapid and simple sample preparation. Isotopically labeled internal standards, Na13C15N and NaS13C15N, were mixed with swine plasma (spiked and nonspiked), proteins were precipitated with acetone, the samples were centrifuged, and the supernatant was removed and dried. The dried samples were reconstituted in 10 mM ammonium formate. Cyanide was reacted with naphthalene-2,3-dicarboxaldehyde and taurine to form N-substituted …


06. Computer Science, University Of Central Oklahoma Jan 2014

06. Computer Science, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


04. Botany, University Of Central Oklahoma Jan 2014

04. Botany, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


09. Environmental Science, University Of Central Oklahoma Jan 2014

09. Environmental Science, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


12. Kinesiology, University Of Central Oklahoma Jan 2014

12. Kinesiology, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


08. Engineering, University Of Central Oklahoma Jan 2014

08. Engineering, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


10. Forensic Science, University Of Central Oklahoma Jan 2014

10. Forensic Science, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.


05. Chemistry, University Of Central Oklahoma Jan 2014

05. Chemistry, University Of Central Oklahoma

Oklahoma Research Day Abstracts

No abstract provided.