Synthesis Of Unsymmetrical Bidentate Ligands From Secondary Phosphine Oxides,
2020
University of Minnesota - Morris
Synthesis Of Unsymmetrical Bidentate Ligands From Secondary Phosphine Oxides, Malachy J. Brink, Ryan Anderson
Student Research, Papers, and Creative Works
Stereochemistry is a key component in the field of asymmetric catalysis. The properties of a molecule can be drastically changed with the change of one stereocenter. Typically, chirality is imparted to a metal by the ligand. "Chiral-at-metal" compounds are unique because the metal complex is chiral, but the ligands are not. Phosphine ligands are notoriously difficult to work with (pyrophoric, toxic, prone to oxidation). The goal of this research was to prepare unsymmetrical bidentate ligands using secondary phosphine oxides, which are air-stable and easy to handle on the benchtop.
Instrument And Application Development In Saturation Recovery And Rapid Scan Electron Paramagnetic Resonance,
2020
University of Denver
Instrument And Application Development In Saturation Recovery And Rapid Scan Electron Paramagnetic Resonance, Joseph E. Mcpeak
Electronic Theses and Dissertations
Enhanced signal sensitivity by the use of Rapid Scan (RS) electron paramagnetic resonance (EPR), a technique that allows for much faster magnetic field scans than traditional field-swept techniques, has facilitated improved data acquisition for many types of samples. For example, irradiated fingernails for radiation dosimetry have been studied using RS-EPR, which resulted in substantial decreases in detection limits. Samarium-mediated reduction mechanisms in organic synthesis have been investigated by RS-EPR providing evidence for a radical intermediate. Spectra of organic radicals exhibiting both narrow lines and closely spaced hyperfine interactions have been recorded via RS-EPR. Well-resolved spectra can be recorded at a …
Nanotoxicity Of Zrs3 Probed In A Bioluminescence Test On E. Coli Bacteria: The Effect Of Evolving H2s,
2020
Derzhavin Tambov State University & National University of Science and Technology “MISIS”
Nanotoxicity Of Zrs3 Probed In A Bioluminescence Test On E. Coli Bacteria: The Effect Of Evolving H2s, Olga Zakharova, Alexander Gusev, Jehad Abourahma, Nataliia S. Vorobeva, Dmitry V. Sokolov, Dmitry S. Muratov, Denis V. Kuznetsov, Alexander Sinitskii
Department of Chemistry: Faculty Publications
Materials from a large family of transition metal trichalcogenides (TMTCs) attract considerable attention because of their potential applications in electronics, optoelectronics and energy storage, but information on their toxicity is lacking. In this study, we investigated the toxicity of ZrS3, a prominent TMTC material, toward photoluminescent E. coli bacteria in a bioluminescence test. We found that freshly prepared ZrS3 suspensions in physiological saline solution with concentrations as high as 1 g/L did not exhibit any toxic effects on the bacteria. However, ZrS3 suspensions that were stored for 24 h prior to the bioluminescence tests were very toxic to the bacteria …
Quantitative Nmr-Based Biomedical Metabolomics: Current Status And Applications,
2020
University of Nebraska-Lincoln
Quantitative Nmr-Based Biomedical Metabolomics: Current Status And Applications, Alexandra A. Crook, Robert Powers
Department of Chemistry: Faculty Publications
Nuclear Magnetic Resonance (NMR) spectroscopy is a quantitative analytical tool commonly utilized for metabolomics analysis. Quantitative NMR (qNMR) is a field of NMR spectroscopy dedicated to the measurement of analytes through signal intensity and its linear relationship with analyte concentration. Metabolomics-based NMR exploits this quantitative relationship to identify and measure biomarkers within complex biological samples such as serum, plasma, and urine. In this review of quantitative NMR-based metabolomics, the advancements and limitations of current techniques for metabolite quantification will be evaluated as well as the applications of qNMR in biomedical metabolomics. While qNMR is limited by sensitivity and dynamic range, …
Methods Ofmaking And Using Lignin Derivatives,
2020
Lincoln, NE
Methods Ofmaking And Using Lignin Derivatives, Mark Alan Helle, Chin Li Cheung
Department of Chemistry: Faculty Publications
Materials and methods for preparing reactive lignin and for preparing a bio-based adhesive are described herein.
Polarization-Independent Metasurface Lens Based On Binary Phase Fresnel Zone Plate,
2020
University of Nebraska - Lincoln
Polarization-Independent Metasurface Lens Based On Binary Phase Fresnel Zone Plate, Jonathan Baine, Jing Tang, Xing Li
Department of Chemistry: Faculty Publications
Based on the binary phase Fresnel zone plate (FZP), a polarization-independent metasurface lens that is able to focus incident light with any polarization state, including circular, linear, and elliptical polarizations, has been proposed and investigated. We demonstrate that the metasurface lens consisting of metal subwavelength slits can operate in a wide bandwidth in the visible range, and has a higher focusing efficiency than that of an amplitude FZP lens without phase modulation. A multi-focus FZP metasurface lens has also been designed and investigated. The proposed lens can provide potential applications in integrated nanophotonic devices without polarization limitations.
Majestic - Prappe Metals Data,
2020
University of Denver
Majestic - Prappe Metals Data, Brian Majestic
Chemistry and Biochemistry: Data Sets
No abstract provided.
Synthesis And Characterization Of Starburst Pseudorotaxanes And Their Metallic Derivatives,
2020
Eastern Illinois University
Synthesis And Characterization Of Starburst Pseudorotaxanes And Their Metallic Derivatives, Shalini D. Kadinappulige
Masters Theses
Mechanically Interlocked Molecules (MIMs) are interlocked molecular architectures, characterized by the fact that they are linked through a mechanical bond. Catenanes, rotaxanes, molecular knots, and Borromean rings are typical examples for these molecules. Since MIMs are not connected by covalent bonds, hydrogen bonding, π- π stacking, and/or electrostatic interactions help bring the components together. Dialkyl-ammonium centers, bis(pyridinium)ethane dications, viologen species, and naphthalenediimide π-deficient groups are well known as recognition motifs for crown ethers. In the research described here, we have synthesized several pseudorotaxanes and their tricyclohexyltin metallic derivatives, based on benzobis(imidazolium) (BBI) salts as axles, in combination with the 15DN38C10 …
Lew,1wr1 Rat Shows An Increased Risk Of Developing Malignant Forms Of Nafld,
2020
University of Alabama in Huntsville
Lew,1wr1 Rat Shows An Increased Risk Of Developing Malignant Forms Of Nafld, Luis Mercado
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
A Comparative Study Of Drug Affinities Determined By Thermofluor And Kinetic Analysis,
2020
Montclair State University
A Comparative Study Of Drug Affinities Determined By Thermofluor And Kinetic Analysis, Oruba Shatnawi
Theses, Dissertations and Culminating Projects
Determining the binding affinity and potency in vitro is one of the significant steps that can give a clue for a new candidate drug during the drug discovery process. Thermofluor is a method used in measuring binding affinity (Kd) of protein-ligands interaction through determining the change in thermal denaturation temperature of protein using real time PCR (RT-PCR). Kinetic analysis assay is used to screen a library of compounds to calculate their potencies (IC50) and inhibition constants (Ki) and it can be performed by spectrophotometer technique. In this study, we used bovine carbonic anhydrase II (BCA II) enzyme, and four of …
Ozone And Reactive Oxidized Nitrogen Chemistry In The Northeast U.S,
2020
University at Albany, State University of New York
Ozone And Reactive Oxidized Nitrogen Chemistry In The Northeast U.S, Matthew Ninneman
Legacy Theses & Dissertations (2009 - 2024)
Ongoing reductions in oxides of nitrogen concentrations ([NOx] = nitric oxide ([NO]) + nitrogen dioxide ([NO2])) throughout the continental United States (U.S.) have important implications for tropospheric ozone (O3) and reactive oxidized nitrogen chemistry (NOy ≈ NOx + nitric acid (HNO3) + particle nitrate (pNO3) + peroxy nitrates (PNs) + alkyl nitrates (ANs)). Specifically, decreasing [NOx] concentrations have likely (1) increased the sensitivity of O3 to the [NOx] level, and (2) affected NOy speciation and partitioning. An understanding of the impacts of continued [NOx] reductions is needed to inform current and future air pollution control strategies, especially since the National …
Metabolic Changes Associated With Adaptive Resistance To Daptomycin In Streptococcus Mitis-Oralis,
2020
University of Nebraska-Lincoln
Metabolic Changes Associated With Adaptive Resistance To Daptomycin In Streptococcus Mitis-Oralis, Allison Parrett, Joseph M. Reed, Stewart G. Gardner, Nagendra N. Mishra, Arnold S. Bayer, Robert Powers, Greg A. Somerville
Department of Chemistry: Faculty Publications
Background: Viridans group streptococci of the Streptococcus mitis-oralis subgroup are important endovascular pathogens. They can rapidly develop high-level and durable non-susceptibility to daptomycin both in vitro and in vivo upon exposure to daptomycin. Two consistent genetic adaptations associated with this phenotype (i.e., mutations in cdsA and pgsA) lead to the depletion of the phospholipids, phosphatidylglycerol and cardiolipin, from the bacterial membrane. Such alterations in phospholipid biosynthesis will modify carbon flow and change the bacterial metabolic status. To determine the metabolic differences between daptomycin-susceptible and non- susceptible bacteria, the physiology and metabolomes of S. mitis-oralis strains 351 (daptomycin-susceptible) and 351-D10 (daptomycin …
Improving The Value Of The Coconut With Biotechnology,
2020
Ateneo de Manila University
Improving The Value Of The Coconut With Biotechnology, Fabian M. Dayrit, Quang Nguyen
Chemistry Faculty Publications
The fruit of the coconut tree is perhaps the most useful plant resource in the tropics. All parts of the coconut fruit have traditional uses that have been developed commercially in recent times (Foale 2003, Dayrit and Dayrit 2013). Due to its widespread household use, trade and industry statistics on coconut products reflect only part of the actual importance of the coconut. Today, coconut-based products have gone beyond the tropics and are consumed in many temperate countries and global regions such as Australia, China, Europe, North America, and the Middle East (Costello 2018). Coconut milk is the basic ingredient of …
Automated Process Of Quantifying Scientific Images Using Fiji,
2020
University of Alabama in Huntsville
Automated Process Of Quantifying Scientific Images Using Fiji, Olivia Casimir
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Using Batman Software To Analyze Metabolic Changes In Type 1 Diabetes-Susceptible Rats,
2020
University of Alabama in Huntsville
Using Batman Software To Analyze Metabolic Changes In Type 1 Diabetes-Susceptible Rats, Connor Hall
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Kidney Tissue Preparation For 1h-Nmr Analysis And Colorimetric Activity Assay Of Mitochondria,
2020
University of Alabama in Huntsville
Kidney Tissue Preparation For 1h-Nmr Analysis And Colorimetric Activity Assay Of Mitochondria, Savannah Knight, James Wolfsberger
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
The Role Of Influenza Infection On Cell Metabolism,
2020
The University of Akron
The Role Of Influenza Infection On Cell Metabolism, Megha Mokkapati
Williams Honors College, Honors Research Projects
In this particular study global metabolomics LCMS data was analyzed to determine the effect of influenza infection on host metabolic processes. Specifically, wild-type male and female mouse lung samples from mice infected with PR8 (H1N1) or both PR8 and a reinfection of X31 (H3N2) were analyzed. The LC/MS(liquid chromatography-mass spectrometry) based global metabolomics will be performed on the samples using hydrophilic interaction liquid chromatography to separate polar analytes from the tissues (Dettmer, Aronov, 2007). Metabolites impacted by influenza infection in all samples will be analyzed to compare male and female mice, as well as differences between PR8 infection and X31 …
Carbon Oxidation State In Microbial Polar Lipids Suggests Adaptation To Hot Spring Temperature And Redox Gradients,
2020
Arizona State University
Carbon Oxidation State In Microbial Polar Lipids Suggests Adaptation To Hot Spring Temperature And Redox Gradients, Grayson M. Boyer, Florence Schubotz, Roger E. Summons, Jade Woods, Everett L. Shock
Department of Chemistry: Faculty Publications
The influence of oxidation-reduction (redox) potential on the expression of biomolecules is a topic of ongoing exploration in geobiology. In this study, we investigate the novel possibility that structures and compositions of lipids produced by microbial communities are sensitive to environmental redox conditions. We extracted lipids from microbial biomass collected along the thermal and redox gradients of four alkaline hot springs in Yellowstone National Park (YNP) and investigated patterns in the average oxidation state of carbon (ZC), a metric calculated from the chemical formulae of lipid structures. Carbon in intact polar lipids (IPLs) and their alkyl chains becomes …
Surface Modification Of Silicon Nanowire Based Field Effect Transistors With Stimuli Responsive Polymer
Brushes For Biosensing Applications,
2020
Institute for Materials Science and Max Bergmann Center of Biomaterials
Surface Modification Of Silicon Nanowire Based Field Effect Transistors With Stimuli Responsive Polymer Brushes For Biosensing Applications, Stephanie Klinghammer, Sebastian Rauch, Sebastian Pregl, Petra Uhlmann, Larysa Baraban, Gianaurelio Cuniberti
Department of Chemistry: Faculty Publications
We demonstrate the functionalization of silicon nanowire based field effect transistors (SiNW FETs) FETs with stimuli-responsive polymer brushes of poly(N-isopropylacrylamide) (PNIPAAM) and poly(acrylic acid) (PAA). Surface functionalization was confirmed by atomic force microscopy, contact angle measurements, and verified electrically using a silicon nanowire based field effect transistor sensor device. For thermo-responsive PNIPAAM, the physicochemical properties (i.e., a reversible phase transition, wettability) were induced by crossing the lower critical solution temperature (LCST) of about 32 ◦C. Taking advantage of this property, osteosarcomic SaoS-2 cells were cultured on PNIPAAM-modified sensors at temperatures above the LCST, and completely detached by simply cooling. Next, …
Rapid And Accurate Determination Of Atomistic Rna Dynamic Ensemble Models Using Nmr And Structure Prediction,
2020
Duke University, Durham & Duke University School of Medicine, Durham
Rapid And Accurate Determination Of Atomistic Rna Dynamic Ensemble Models Using Nmr And Structure Prediction, Honglue Shi, Atul Rangadurai, Hala Abou Assi, Rohit Roy, David A. Case, Daniel Herschlag, Joseph D. Yesselman, Hashim M. Al-Hashimi
Department of Chemistry: Faculty Publications
Biomolecules form dynamic ensembles of many inter-converting conformations which are key for understanding how they fold and function. However, determining ensembles is challenging because the information required to specify atomic structures for thousands of conformations far exceeds that of experimental measurements. We addressed this data gap and dramatically simplified and accelerated RNA ensemble determination by using structure prediction tools that leverage the growing database of RNA structures to generate a con- formation library. Refinement of this library with NMR residual dipolar couplings provided an atomistic ensemble model for HIV-1 TAR, and the model accuracy was independently sup- ported by comparisons …
