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Identification Of A Phytotoxic Fungus And An Investigation Into The Isolation Of Its Phytotoxic Constituents, William E. Briscoe

Honors Theses

A fungus was isolated from Hedera helix (English ivy) leaves experiencing necrosis and identified as Diaporthe eres by molecular techniques. The fungus was grown in potato dextrose broth medium and the culture medium was extracted with ethyl acetate. Bioassay guided fractionation of ethyl acetate extract of culture filtrate of this fungus led to the isolation of two phytotoxic compounds that are active against the seed germination of the monocotyledon Agrostis stolonifera at 1 mg mL-1. Structures of these active compounds were determined by spectroscopic methods and were determined 8-hydroxy-3.7-dimethylisochroman-1-one and 2-(4-hydroxyphenyl)-ethanol. This is the first finding presented on the phytotoxic …

Evaluating The Efficacy Of Small Basis Sets And The Counterpoise Procedure To Reproduce Complete Basis Set Limit Higher-Order Correlation Corrections For Weakly Bound Molecular Clusters, Cara M. Thorne

Honors Theses

The efficacy of small basis sets and the counterpoise procedure to accurately reproduce higher-order correlation corrections, which are routinely employed to estimate CCSD(T) interaction energies at the complete basis set (CBS) limit using an additive scheme, was examined through the study of four dispersion-dominated dimer systems. The dimers of acetylene (HCCH), cyanogen (NCCN), diphosphorous (P2) and 1,4-diphosphabutadiyne (PCCP) were studied in three different configurations: cross, parallel-displaced and t-shaped at the intermolecular distance corresponding to the minimum point on the CCSD(T) potential energy curve (PEC) for each system using MP2, CCSD and CCSD(T) methods in conjunction with eight basis sets from …

Metabolomic Analysis Of Liver Tissue From The Vx2 Rabbit Model Of Secondary Liver Tumors, R. Ibarra, J. E. Dazard, Y. Sandlers, F. Rehman, R. Abbas, R. Kombu, G. F. Zhang, H. Brunengraber, J. Sanabria

Chemistry Faculty Publications

Purpose. The incidence of liver neoplasms is rising in USA. The purpose of this study was to determine metabolic profiles of liver tissue during early cancer development. Methods. We used the rabbit VX2 model of liver tumors (LT) and a control group consisting of sham animals implanted with Gelfoam into their livers (LG). After two weeks from implantation, liver tissue from lobes with and without tumor was obtained from experimental animals (LT+/LT-) as well as liver tissue from controls (LG+/LG-). Peaks obtained by Gas Chromatography-Mass Spectrometry were subjected to identification. 56 metabolites were identified and their profiles compared between groups …

Speciation Of Chromium By The Combination Of Dispersive Liquid--Liquid Microextraction And Microsample Injection Flame Atomic Absorption Spectrometry, Yunusemre Ünsal, Mustafa Tüzen, Mustafa Soylak

Turkish Journal of Chemistry

A microextraction procedure was established for the speciation of total Cr, Cr(III), and Cr(VI). Sudan blue II was used as a ligand for speciation works. Some factors affecting the recoveries of chromium species, including type of extraction and dispersive solvents, pH, ligand amount, extraction time, and matrix ions, were examined. Optimum values for the dispersive liquid--liquid microextraction method were pH 6, LOD 0.34 \mu g L^{-1}, and preconcentration factor 400. Chromium(III) was quantitatively recovered under optimal conditions, while the recovery of chromium(VI) was below 10%. The relative standard deviation for Cr(III) determinations for the 10-replicate measurement of 0.3 \mu g …

Synthesis And X-Ray Powder Diffraction, Electrochemical, And Genotoxic Properties Of A New Azo-Schiff Base And Its Metal Complexes, Mustafa Bal, Gökhan Ceyhan, Bariş Avar, Muhammet Köse, Ahmet Kayraldiz, Mükerrem Kurtoğlu

Turkish Journal of Chemistry

A new, substituted 2-[(E)-{[4-(benzyloxy)phenyl]imino} methyl]-4-[(E)-(4-nitrophenyl)diazenyl]phenol azo-azomethine ligand (mbH) was synthesized from 2-hydroxy-5-[(4-nitrophenyl)diazenyl]benzaldehyde and 4-benzyloxyanilinehydrochloride in ethyl alcohol solution. These mononuclear Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes of the ligand were prepared and their structures were proposed by elemental analysis, and infrared and ultraviolet-visible spectroscopy; the proton NMR spectrum of the mbH ligand was also recorded. The azo-azomethine ligand, mbH, behaves as a bidentate ligand coordinating through the nitrogen atom of the azomethine (--CH=N--) and the oxygen atom of the phenolic group. Elemental analyses indicated that the metal:ligand ratio was 1:2 in the metal chelates. Powder X-ray diffraction parameters suggested …

Spectrophotometric Determination Of Molybdenum Using Surfactant-Mediated Liquid--Liquid Extraction, Rameshwar Dass, Jitander Kumar Kapoor, Sunita Gambhir

Turkish Journal of Chemistry

A new spectrophotometric method has been developed for determination of molybdenum using surfactant-mediated liquid--liquid extraction. Molybdenum(V) obtained by ascorbic acid reduction in 2.5 M H_2SO_4 reacted spontaneously with thiocyanate and cetyl trimethyl ammonium bromide (CTAB), forming an intense orange yellow complex that was extracted quantitatively into 1,2-dichloroethane and absorbed at 460 nm. The absorbance of the extract was found to be stable for more than 24 h. Beer's law was obeyed over the concentration range 0.1--4.2 \mu g Mo mL^{-1} of the extract. The linear range for an accurate determination was found to be 1.2--2.6 \mu g Mo mL^{-1}. The …

An Efficient Synthesis Of Some New Bisbenzimidazoles Via Microwave Technique, Bahi̇tti̇n Kahveci̇, Nesri̇n Karaali̇, Fati̇h Yilmaz, Emre Menteşe

Turkish Journal of Chemistry

2,2'-[1,4 (1,3)-Phenylenedi(methylene)]bis-1H-benzimidazole derivatives were obtained from the reaction of 1,4- or (1,3)-bisiminoester hydrochloride and o-phenylenediamine derivatives under microwave irradiation. Ester and hydrazide derivatives were prepared from a free NH group. This practical method revealed good results for yield, reaction time, and quick isolation of products.

Novel N-Acyl/Aroyl-2-(5-Phenyl-2h-Tetrazol-2-Yl)Acetohydrazides: Synthesis And Characterization, Aamer Saeed, Majid Hussain, Muhammad Qasim

Turkish Journal of Chemistry

A number of novel N-acyl/aroyl-2-(5-phenyl-2H-tetrazol-2-yl)acetohydrazides (4a--j) of biological interest were efficiently synthesized by treating 2-(5-phenyl-2H-tetrazole-2-yl)acetohydrazide (3) with a variety of aroyl/hetero- cyclyl or alkanoyl chlorides. FTIR, ^1H NMR, ^{13}C NMR, GC-MS, and elemental analyses data confirmed the structures assigned to the newly synthesized compounds.

Synthesis, Spectral Characterisation, Electrochemical, And Fluorescence Studies Of Biologically Active Novel Schiff Base Complexes Derived From E-4-(2-Hydroxy-3-Methoxybenzlideneamino)-N-(Pyrimidin-2-Yl)Benzenesulfonamide, Valarmathy Govindaraj, Subbalakshmi Ramanathan

Turkish Journal of Chemistry

A new Schiff base was prepared from 2-sulphanilamidopyrimidine and 2-hydroxy-3-methoxybenzaldehyde in ethanolic media and it was complexed with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) ions. The synthesised ligand and complexes were characterised by IR, UV, ^1H and ^{13}C NMR, elemental analysis, cyclic voltammetry, EPR, molar conductance, and magnetic susceptibility. The reasonable shifts in FT-IR and NMR spectral signals of the complexes with respect to the free ligand confirm good coordination of the Schiff-base ligand with the metal through imine nitrogen and oxygen atoms of Schiff base moiety. The Schiff-base ligand and the complexes were screened for antimicrobial activity and fluorescent …

Synthesis And Properties Of Novel Polymeric Metal-Free And Metallophthalocyanines Containing Peripherally Long 1,2-Bis[(3-Oxapropyl)Oxa]Benzene Derivatives, Ahmet Bi̇lgi̇n, Durmuş Yanmaz, Çi̇ğdem Yağci

Turkish Journal of Chemistry

New polymeric phthalocyanine moieties (M = 2H, Zn, Ni, Cu, and Co) were synthesized via polytetracyclomerization reaction of o-bis[3-(3,4-dicyanophenoxy)propyloxy]benzene (3), which can be obtained by the reaction of 4-nitrophthalonitrile with o-bis[(3-hydroxypropyl)oxy]benzene. Aggregation and disaggregation behavior of the polymeric phthalocyanine (5) was studied with some alkali and earth alkali metal cations. Measured intrinsic viscosities of the polymeric phthalocyanines exhibited a substantial decreasing tendency with dilution of the solution. Thermogravimetric analysis was performed under air by using DSC and DTG/TGA techniques and indicated that these polymers have good thermal stability. AC and DC electrical conductivities of the polymeric phthalocyanines were investigated in …

Modeling Of An Upper Midwest Forest Boundary Layer And Vehicle Indoor Air Quality, Phillip Stratton

Master's Theses and Doctoral Dissertations

The key to understanding tropospheric chemistry begins with the hydroxyl and hydroperoxy radicals. Recent research suggests that there is still considerable uncertainty in our understanding of the sources of these radicals and their role as sinks. The work detailed in this thesis describes a computational approach to modeling the hydroxyl and hydroperoxy radicals in a forest environment and attempts to shed further light on the radical budget in a typical Northern Hardwood forest. Additionally, research was conducted with United States Council for Automotive Research in collaboration with Ford, General Motors, and Chrysler to develop a global standard for vehicle indoor …

Determination Of The Uptake And Effects Of Tio2 Nanoparticles In Cucumber (Cucumis Sativus), Alia D. Servin

Open Access Theses & Dissertations

The profuse use of nanoparticles (NPs) in consumer products has raised concerns about their impacts in environmental and human health and possible transfer into the food chain through plants. Cucumber (Cucumis sativus L.) is a widely cultivated garden vegetable that could be in contact with NPs through biosolids. In this Dissertation research, the impact of TiO2 NPs was evaluated in cucumber plants grown in hydroponics and sandy loam soil. Hydroponically grown plants were treated for 15 days with 0-4000 mg/L of TiO2 NPs, and their vegetative tissues were studied using synchrotron micro X-Ray Fluorescence (micro-XRF) and Micro X-ray Absorption Near …

Spectroscopic Analyses Of Factors Affecting Formation And Stability Of I-Motif Dna, Samantha Michelle Reilly

Electronic Theses and Dissertations

The four-stranded i-motif (iM) conformation of DNA has importance to a variety of biochemical systems that include nanomaterials and oncogene regulation. Fundamental studies to understand iM formation and its structure in solution still remain to be done. In this dissertation, we will discuss the use of the fluorescent base analog tC° to determine the structural state of DNA in solution. We will also demonstrate the use of tC° to determine both the hydrodynamic properties and the folding mechanism of an iM. We also determined the loop length dependence on iM formation and stability. Our hydrodynamic studies show that the iM …

Characterization Of Initial Iron Binding Location And The Structure/Iron Binding Site On S.Cerevisiae Isu And On D.Melanogaster Frataxin, Andria V. Rodrigues

Wayne State University Dissertations

Iron-induced free radical damage has been implicated in the pathology of diseases of iron overload such as Friedreich's Ataxia, a genetic disorder characterized by an accumulation of iron in actively metabolizing tissues ultimately leading to cardio- and neuro- degeneration and cell death. It is caused by an inability to synthesize the mitochondrial protein, frataxin. Frataxin has been shown by numerous groups to be a part of the iron-sulfur cluster (ISC) multicomplex, where it functions in the capacity of a potential iron provider and an allosteric modulator of both the cysteine desulfurase and scaffold protein ISU. My research has been focused …

Elemental Fingerprinting Using Inductively Coupled Plasma Mass Spectrometry And Chemometrics: Application To Environmental Science And Provenance Studies, Lorlyn Paquibot Reidy

Electronic Theses and Dissertations

No abstract provided.

Identification And Characterization Of Functionally Critical, Conserved Motifs In The Internal Repeats And N-Terminal Domain Of Yeast Translation Initiation Factor 4b (Yeif4b), Sarah F. Mitchell

Chemistry and Biochemistry Faculty Works

EIF4B has been implicated in attachment of the 43 S preinitiation complex (PIC) to mRNAs and scanning to the start codon. We recently determined that the internal seven repeats (of ∼26 amino acids each) of Saccharomyces cerevisiae eIF4B (yeIF4B) compose the region most critically required to enhance mRNA recruitment by 43 S PICs in vitro and stimulate general translation initiation in yeast. Moreover, although the N-terminal domain (NTD) of yeIF4B contributes to these activities, the RNA recognition motif is dispensable. We have now determined that only two of the seven internal repeats are sufficient for wildtype (WT) yeIF4B function in …

Structure And Dynamics Of The Hiv-1 Frameshift Element Rna, Kathryn Mouzakis

Chemistry and Biochemistry Faculty Works

The HIV-1 ribosomal frameshift element is highly structured, regulates translation of all virally encoded enzymes, and is a promising therapeutic target. The prior model for this motif contains two helices separated by a three-nucleotide bulge. Modifications to this model were suggested by SHAPE chemical probing of an entire HIV-1 RNA genome. Novel features of the SHAPE-directed model include alternate helical conformations and a larger, more complex structure. These structural elements also support the presence of a secondary frameshift site within the frameshift domain. Here, we use oligonucleotide-directed structure perturbation, probing in the presence of formamide, and in-virion experiments to examine …

Principles And Properties Of Eukaryotic Mrnps, Sarah F. Mitchell

Chemistry and Biochemistry Faculty Works

The proper processing, export, localization, translation, and degradation of mRNAs are necessary for regulation of gene expression. These processes are controlled by mRNA-specific regulatory proteins, noncoding RNAs, and core machineries common to most mRNAs. These factors bind the mRNA in large complexes known as messenger ribonucleoprotein particles (mRNPs). Herein, we review the components of mRNPs, how they assemble and rearrange, and how mRNP composition differentially affects mRNA biogenesis, function, and degradation. We also describe how properties of the mRNP "interactome" lead to emergent principles affecting the control of gene expression.

Modified Seed Growth Of Iron Oxide Nanoparticles In Benzyl Alcohol: Magnetic Nanoparticles For Radio Frequency Hyperthermia Treatment Of Cancer, Stanley E. Gilliland Iii

Theses and Dissertations

Iron oxide nanoparticles have received sustained interest for biomedical applications as synthetic approaches are continually developed for precise control of nanoparticle properties. This thesis presents an investigation of parameters in the benzyl alcohol synthesis of iron oxide nanoparticles. A modified seed growth method was designed for obtaining optimal nanoparticle properties for magnetic fluid hyperthermia. With a one or two addition process, iron oxide nanoparticles were produced with crystallite sizes ranging from 5-20 nm using only benzyl alcohol and iron precursor. The effects of reaction environment, temperature, concentration, and modified seed growth parameters were investigated to obtain precise control over properties …

Fabrication And Characterization Of High Surface Area Gold Electrodes, Madhura S. Damle

Theses and Dissertations

High surface area gold electrodes are very good substrates for biosensors, catalysis and drug delivery. Their performance is characterized by good sensitivity, low detection limit and high signal. As a result, extensive research is being carried out in this field using different approaches of fabrication to generate high surface area porous electrodes of different morphology, pore size and structure. The morphology of the electrodes can be changed based on whether the approach involves a template or not, types of metal deposition, method and time of dealloying etc. The deposition of metal can be carried out using various approaches such as …

Investigating Dna Barcoding Potentials And Genetic Structure In Ozobranchus Spp. From Atlantic And Pacific Ocean Sea Turtles, Triet Minh Truong

Browse all Theses and Dissertations

The Ozobranchidae family is the smallest and least studied hirudinean taxon. Our research includes the largest molecular dataset yet reported for marine ozobranchids (Ozobranchus margoi and Ozobranchus branchiatus) with the most number of documented turtle hosts (57) from the Atlantic and Pacific Oceans to date of any marine turtle epibiont study. Turtle species sampled in this study include loggerheads (Caretta caretta), hawksbill (Eretmochelys imbricata), olive ridley (Lepidochelys olivacea), and green turtles (Chelonia mydas). Phylogenetic analyses of mitochondrial (COI) and nuclear ribosomal (18S and 28S) genes all support the monophyly of marine Ozobranchidae leeches with speciation occurring over an extensive period …

A Chemical Free Approach For Increasing The Biochemical Surface-Enhanced Raman Spectroscopy (Sers)-Based Sensing Capabilities Of Colloidal Silver Nanoparticles, Kevin Michael Dorney

Browse all Theses and Dissertations

The unique optoelectronic properties of silver nanoparticles (AgNPs) have led to their explosive use in a multitude of both research and industrial settings in recent years. Localized surface plasmon resonance (LSPR) exhibited by AgNPs has been exploited extensively as a nano-scale probe in a variety of spectroscopic detection modalities, particularly in surface-enhanced Raman spectroscopy (SERS). The SERS effect is highly dependent upon the LSPR interaction with optical laser frequencies, thus optimization of LSPR via specific control of AgNP dimensionality and composition of the surrounding medium is vital for increasing the efficacy of SERS-based nano-sensing. This work aimed to augment LSPR …

Stop Cheating!: An Evaluation Of A Scientific Integrity Writing Strategy In General Chemistry I, Michelle L. Edwards

Browse all Theses and Dissertations

Cheating in America has become an epidemic, which has unfortunately spread to academia. Researchers have long been interested in the trends in cheating behavior and the factors that influence these trends among undergraduate college students. Though cheating can take on many forms, in science, there is a deep concern about scientific misconduct related to research. Because training for future scientists begins in undergraduate courses, this study investigated the use of scientific integrity writing strategy in General Chemistry I at Wright State University. The goal of the study was to determine if providing scientific integrity and ethics training, while teaching students …

Routes To N-Heterocycle Functionalized Poly(Arylene Ether Sulfone)S, Jesse L. Picker

Browse all Theses and Dissertations

The synthesis of poly(arylene ether sulfone)s, with a pendant aryl iodide, was achieved via nucleophilic aromatic substitution (NAS) polycondensation of 3-iodo-3',5'-difluoro-diphenylsulfone. The polymer series was subjected to amino acid promoted, copper catalyzed coupling reactions with various N-heterocycles. The resulting polymers became crosslinked and insoluble in any organic solvents. The iodo monomer was then subjected to an amino acid promoted, copper catalyzed coupling reaction with carbazole. The successful synthesis of 3'-(9-carbazole) 3,5-difluorodiphenylsulfone is reported. A series of PAES containing a carbazole substituent were synthesized and characterized. The polymers were characterized by a combination of NMR spectroscopy, SEC, TGA, DSC, UV-Vis spectroscopy. …

Traceability Implementation In Organic Farming: Case Study, Chamomile Tea Production, Shaima Ibrahim

Theses and Dissertations

Implementing a traceability plan in an herbal production plant is a complex task. In this study an attempt to integrate food safety, quality and traceability through the different stages of the organic German Chamomile (Matricaria recutita) production chain was made. First, all the current relevant international laws, regulations and standards regarding traceability, safety and quality, with emphasis on how and why they are necessary for any food production chain, were set forward. Second, physico-chemical and microbiological analyses were run throughout the different processing stages of production, for four different Chamomile batches produced over the same season using the same farming …

Ferroelectric Hexagonal And Rhombic Monolayer Ice Phases, Wen-Hui Zhao, Jaeil Bai, Lan-Feng Yuan, Jinlong Yang, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Two new phases of water, the mid-density hexagonal monolayer ice and the high-density flat rhombic monolayer ice, are observed in our molecular dynamics simulations of monolayer water confined between two smooth hydrophobic walls. These are in addition to the two monolayer ices reported previously, namely, the low-density 4∙8² monolayer ice and the high-density puckered rhombic monolayer ice (HD-pRMI). Stabilities of the structures are confirmed by ab initio computation. Importantly, both new phases and the HD-pRMI are predicted to be ferroelectric. An in-plane external electric field can further stabilize these ferroelectric monolayer ices.

Mvapack: A Complete Data Handling Package For Nmr Metabolomics, Bradley Worley, Robert Powers

Robert Powers Publications

Data handling in the field of NMR metabolomics has historically been reliant on either in-house mathematical routines or long chains of expensive commercial software. Thus, while the relatively simple biochemical protocols of metabolomics maintain a low barrier to entry, new practitioners of metabolomics experiments are forced to either purchase expensive software packages or craft their own data handling solutions from scratch. This inevitably complicates the standardization and communication of data handling protocols in the field. We report a newly developed open-source platform for complete NMR metabolomics data handling, MVAPACK, and describe its application on an example metabolic fingerprinting data set.

Iterative Assembly Of Two Separate Polyketide Chains By The Same Single-Module Bacterial Polyketide Synthase In The Biosynthesis Of Hsaf, Yaoyao Li, Haotong Chen, Yanjiao Ding, Yunxuan Xie, Haoxin Wang, Ronald Cerny, Yuemao Shen, Liangcheng Du

Ronald Cerny Publications

HSAF (1) was isolated from the biocontrol agent Lysobacter enzymogenes (Figure 1).^[1-4]

This bacterial metabolite belongs to polycyclic tetramate macrolactams (PTM) that are

emerging as a new class of natural products with distinct structural features. ^{[5, 6]} HSAF

exhibits a potent antifungal activity and shows a novel mode of action.^[1-4] The HSAF

biosynthetic gene cluster contains only a single-module hybrid polyketide synthasenonribosomal

peptide synthetase (PKS-NRPS), although the PTM scaffold is apparently

derived from two separate hexaketide chains and an ornithine residue.^[1-4] This suggests that

the same PKS module would act not only iteratively, but also …

Phosphatase-Inert Glucosamine 6‑Phosphate Mimics Serve As Actuators Of The Glms Riboswitch, Xiang Fei, Thomas Holmes, Julianna Diddle, Lauren Hintz, Dan Delaney, Alex Stock, Danielle Renner, Molly Mcdevitt, David B. Berkowitz, Juliane K. Soukup

David Berkowitz Publications

The glmS riboswitch is unique among generegulating riboswitches and catalytic RNAs. This is because its own metabolite, glucosamine-6-phosphate (GlcN6P), binds to the riboswitch and catalytically participates in the RNA selfcleavage reaction, thereby providing a novel negative feedback mechanism. Given that a number of pathogens harbor the glmS riboswitch, artificial actuators of this potential RNA target are of great interest. Structural/kinetic studies point to the 2- amino and 6-phosphate ester functionalities in GlcN6P as being crucial for this actuation. As a first step toward developing artificial actuators, we have synthesized a series of nine GlcN6P analogs bearing phosphatase-inert surrogates in place …

Highly Selective Gas Sensor Arrays Based On Thermally Reduced Graphene Oxide, Alexey Lipatov, Alexey Varezhnikov, Peter Wilson, Victor Sysoev, Andrei Kolmakov, Alexander Sinitskii

Department of Chemistry: Faculty Publications

The electrical properties of reduced graphene oxide (rGO) have been previously shown to be very sensitive to surface adsorbates, thus making rGO a very promising platform for highly sensitive gas sensors. However, poor selectivity of rGO-based gas sensors remains a major problem for their practical use. In this paper, we address the selectivity problem by employing an array of rGO-based integrated sensors instead of focusing on the performance of a single sensing element. Each rGO-based device in such an array has a unique sensor response due to the irregular structure of rGO films at different levels of organization, ranging from …