Chemistry Commons^™

Small Studies, Big Decisions: The Role Of Pilot/Feasibility Studies In Incremental Science And Premature Scale-Up Of Behavioral Interventions, Michael William Beets, Lauren Von Klinggraeff, Robert G. Weaver, Bridget Ryan Armstrong, Sarah Burkart

Faculty Publications

Background: Careful consideration and planning are required to establish “sufficient” evidence to ensure an investment in a larger, more well-powered behavioral intervention trial is worthwhile. In the behavioral sciences, this process typically occurs where smaller-scale studies inform larger-scale trials. Believing that one can do the same things and expect the same outcomes in a larger-scale trial that were done in a smaller-scale preliminary study (i.e., pilot/feasibility) is wishful thinking, yet common practice. Starting small makes sense, but small studies come with big decisions that can influence the usefulness of the evidence designed to inform decisions about moving forward with a …

Emergence Of Non-Hexagonal Crystal Packing Of Deswollen And Deformed Ultra-Soft Microgels Under Osmotic Pressure Control, Molla R. Islam, Rachel Nguyen, L. Andrew Lyon

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Highly solvent swollen poly(N-isopropylacrylamide-co-acrylic acid) microgels are synthesized without exogenous crosslinker, making them extremely soft and deformable. These ultralow crosslinked microgels (ULC) are incubated under controlled osmotic pressure to provide a slow (and presumably thermodynamically controlled) approach to higher packing densities. It is found that ULC microgels show stable colloidal packing over a very wide range of osmotic pressures and thus packing densities. Surprising observation of co-existence between hexagonal and square lattices is also made over the lower range of studied osmotic pressures, with microgels apparently changing shape from spheres to cubes in defects or grain boundaries. It is proposed …

Analysis Of The Electronic Effects And Reactivity Of Benzhydrols In The Formation Of Benzhydryl Ethers, Katherine Quesada, Daniel Chabeda, Jaeger Johnson, Alex Shore

The Yale Undergraduate Research Journal

Benzhydryl ethers were synthesized through the use of microwave irradiation in a proto-ionic liquid solvent. The resulting products were separated from the reaction mixture by vacuum filtration with a silica gel plug. The products were analyzed using GCMS and 1 H NMR techniques to identify and quantify products. Analysis of the resultant data indicated the syntheses of the desired benzhydryl products were successful for 4,4-dimethoxybenzhydrol (conversion: 83% (1-propyl ether), 11% (2-propyl ether), 11% (menthyl ether)) and 4,4-dimethylbenzhydrol (conversion to desired product: 100% (1-propyl ether), 100% (2-propyl ether), 26% (menthyl ether)). However, the syntheses were unsuccessful for reactant 4,4-difluorobenzhydrol and benzhydrol. …

Spectral Analysis Of A New Electronic Transition Of Platinum Fluoride, Ptf, Carol Welch

Undergraduate Research Symposium

The electronic landscape of platinum containing molecules has been the focus of numerous spectroscopic studies in recent years, because of the difficulty in describing electronic structure theoretically due to electronic correlations and relativistic effects. A collective effort by spectroscopitsts and theoreticians to investigate the diatomic molecule platinum fluoride, PtF, has included research such as developing potential energy diagrams and performing analyses on rotational transitions with microwave spectroscopy. One group observed electronic transitions of PtF using laser vaporization/reaction with jet free expansion and laser induced spectroscopy. A highly effective method for observing and analyzing electronic transitions of small, metal-containing molecules like …

Pressure-Induced Polymorphic Transformations Of Ethylenediamine Bisborane, Rongfeng Guan, Pan Wang, Yang Song, Viktor N. Staroverov

Chemistry Publications

Pressure-induced phase transitions of crystalline ethylenediamine bisborane (EDAB), a prospective hydrogen storage material, are investigated using vibrational spectroscopy, X-ray diffraction, evolutionary crystal structure prediction, and density functional theory. The results indicate that EDAB undergoes two transitions in the 0–17 GPa pressure range: the first one is near 1 GPa, from the orthorhombic ambient-pressure Pbca structure (phase I) to a monoclinic structure of P21/c symmetry (phase II); the second is near 7 GPa, from phase II to another P21/c structure (phase III). The latter coexists with phase II and remains the most stable form of EDAB up …

An Examination Of Factors Influencing Small Proton Chemical Shift Differences In Nitrogen-Substituted Monodeuterated Methyl Groups, Stuart J. Elliott, O. Maduka Ogba, Lynda J. Brown, Daniel J. O'Leary

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Monodeuterated methyl groups have previously been demonstrated to provide access to long-lived nuclear spin states. This is possible when the CH₂ D rotamers have sufficiently different populations and the local environment is chiral, which foments a non-negligible isotropic chemical shift difference between the two CH₂ D protons. In this article, the focus is on the N-CH₂ D group of N-CH₂ D-2-methylpiperidine and other suitable CH₂ D piperidine derivatives. We used a combined experimental and computational approach to investigate how rotameric symmetry breaking leads to a ¹H CH₂ D chemical shift …

Systematic And Collaborative Approach To Problem Solving Using X-Ray Photoelectron Spectroscopy, Neal Fairley, Vincent Fernandez, Mireille Richard-Plouet, Catherine Guillot-Deudon, John Walton, Emily Smith, Delphine Flahaut, Mark Greiner, Mark Biesinger, Sven Tougaard, David Morgan, Jonas Baltrusaitis

Chemistry Publications

The methodology presented within this work is a result of years of interactions between many junior and senior X-ray Photoelectron Spectroscopy (XPS) users operating within the CasaXPS spectral processing and interpretation program framework. In particular, discussions arising from a series of workshops have been a significant source for developing the overall XPS data processing concept and are the motivation for creating this work. These workshops organized by the Institut des Matériaux Jean Rouxel (IMN), Nantes gather both experienced and novice users of XPS for a week of discourse in conceptual experiment design and the resulting data processing. However, the framework …

Bioaccessibility And Reactivity Of Alloy Powders Used In Powder Bed Fusion Additive Manufacturing, Yolanda S. Hedberg

Chemistry Publications

Exposure to metal particles via the inhalation route unavoidably takes place at occupational settings during additive manufacturing of metals and alloys. This calls for investigations on possible adverse health effects. This study focuses on virgin and reused powders of three iron- and nickel-based alloy powders (316L, IN718, 18Ni300) widely used in additive manufacturing, and dust powder of 18Ni300 generated during laser melting. Investigations were performed from a physico-chemical and toxicological perspective assessing their bioaccessibility in artificial lysosomal fluid (ALF, simulating lung exposure to respirable particles), corrosion behavior, surface morphology and composition, microstructure, hydrodynamic size distribution in ALF, and in-vitro toxicity …

Citation Patterns In Chemistry Dissertations At A Mid-Sized University: An Internal Citation Analysis And External Comparison, Lisa M. Rose-Wiles

Library Publications

This study analyzes the references cited in 34 chemistry dissertations and compares the results with an earlier study of citations in American Chemical Society journals. The dissertations cite more references and older references and a greater diversity of sources. They have the same tendency to heavily cite journal articles from a small core of traditional journals. This study underscores the value of comparing internal citation analyses with external citation analyses, and of analyzing the number of citing authors as well as the number of citations. Interlibrary loan and internal usage statistics were also used to inform collection development and library …

College Of Natural Sciences Newsletter, September 2021, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 2, Issue 9.

Page 1 Dean's Message
Page 2 Awards and Recognition
Page 3 Student Clubs in Natural Science
Page 4 Media Coverage of CNS
Page 5 Hobo Day Festivities
Page 6 Open PRAIRIE Data; Grants Awarded in CNS
Page 7 One Day for State Recap

Utah - Perry Port Of Entry 2020, University Of Denver

FEAT Heavy-Duty Vehicle Measurements

Relevant Publications

Environmental Science & Technology publication.

Utah DEQ Final Report

Washington - Feat Bridge Based Train Measurements 2012, University Of Puget Sound

Non-Road Vehicle Data

Relevant Publications

Atmospheric Environment Publication (2019)

Laboratory Capabilities, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about the Energy & Environmental Research Center’s laboratory capabilities including reservoir characterization, organic geochemistry, fluid sampling, and material analysis. A list of publications and laboratory information is also included.

Instrumentation For Routine Analysis Of Acrylamide In French Fries: Assessing Limitations For Adoption, Mark M. Skinner, Jared T. Seale, Maranda S. Cantrell, Joseph M. Collins, Matthew W. Turner, Owen M. Mcdougal

Chemistry and Biochemistry Faculty Publications and Presentations

The purpose of this experimental review was to detect acrylamide in French fries using methods most adaptable to the food process industry for quality control assessment of products. French fries were prepared at different cook times using the same fryer oil over a five-day period to assess the influence of oil degradation and monitor trends in acrylamide formation. Acrylamide detection was performed using LC-MS, GC-MS and FT-NIR. The low levels of acrylamide produced during frying, low molecular weight of the analyte, and complexity of the potato matrix make routine acrylamide measurement challenging in a well-outfitted analytical lab with trained personnel. …

Genotype, Age, Genetic Background, And Sex Influence Epha2-Related Cataract Development In Mice, Alpana Dave, Jamie E. Craig, Mohammad Alamein, Karina Skrzypiec, Justin Beltz, Annalise Pfaff, Kathryn P. Burdon, Nuran Ercal, Robb U. De Iongh, Shiwani Sharma

Chemistry Faculty Research & Creative Works

PURPOSE. Age-related cataract is the leading cause of blindness worldwide. Variants in the EPHA2 gene increase the disease risk, and its knockout in mice causes cataract. We investigated whether age, sex, and genetic background, risk factors for age-related cataract, and Epha2 genotype influence Epha2-related cataract development in mice.

METHODS. Cataract development was monitored in Epha2⁺/⁺, Epha2^+/-, and Epha2^-/- mice (Epha2^{Gt(KST085)Byg}) on C57BL/6J and FVB:C57BL/6J (50:50) backgrounds. Cellular architecture of lenses, endoplasmic reticulum (ER) stress, and redox state were determined using histological, molecular, and analytical techniques.

RESULTS. Epha2^-/- and Epha2^{+/- …}

Automated Code Engine For Tensor Hypercontraction: Derivation, Optimization And Implementation Of Rank-Reduced Coupled Cluster Theories, Yao Zhao

Dissertations, Theses, and Capstone Projects

The ultimate goal of electronic structure theory is solving the electronic Schr¨odinger Equation. However, even accurate approximations of solving Schr¨odinger Equation, such as high order coupled cluster theories, require computational efforts that are too demanding to be applied on large chemical systems. This thesis tackles the problem of curse of dimensionality: how to reduce the time complexity of high-accuracy coupled cluster methods in order to accelerate computations of molecular energy. On one hand, we believe that low-rank approximation (i.e. Tensor HyperContraction) of high-order tensors appearing in coupled cluster theory is a promising way to achieve rank-reduced coupled cluster theory. On …

Development Of An Lcms Analytical Method With Applicability To Determination Of Trace Level Explosives In Environmental Waters, Cristina I. Veresmortean

Dissertations, Theses, and Capstone Projects

Traces of explosives and their degradation products present in explosives contaminated sites from military sources, such as training facilities, impose a great concern over the public health and our eco-system. This work is centered around finding an efficient way to extraction of these chemicals from water samples and their analysis using advanced separation technology: LC-MS/MS Shimadzu Prominence 8050 and AB Sciex Trap 4000 LC-MS/MS. Different extraction methods will be proposed, along with chromatographic and mass spectroscopy method development. Dependent on the target analyte polarity, thermal degradation, solubility and type of matrix, an appropriate method of analysis will be established. The …

Enhanced Platinum (Ii) Drug Delivery For Anti-Cancer Therapy, Marek T. Wlodarczyk

Dissertations, Theses, and Capstone Projects

Over the years, anti-cancer therapies have improved the overall survival rate of patients. Nevertheless, the traditional free drug therapies still suffer from side effects and systemic toxicity, resulting in low drug dosages in the clinic. This often leads to suboptimal drug concentrations reaching cancer cells, contributing to treatment failure and drug resistance. Among available anti-cancer therapies, metallodrugs are of great interest. Platinum (II)-based agents are highly potent and are used to treat many cancers, including ovarian cancer (OC). Cisplatin (cis-diaminedichloroplatinum (II)) is the first Food and Drug Administration (FDA)-approved metallodrug for treatment of solid tumors, and its mechanism …

Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang

Dissertations, Theses, and Capstone Projects

Nature usually divides complex systems into smaller building blocks specializing in a few tasks since one entity cannot achieve everything. Therefore, self-assembly is a robust tool exploited by Nature to build hierarchical systems that accomplish unique functions. The cell membrane distinguishes itself as an example of Nature’s self-assembly, defining and protecting the cell. By mimicking Nature’s designs using synthetically designed self-assemblies, researchers with advanced nanotechnological comprehension can manipulate these synthetic self-assemblies to improve many aspects of modern medicine and materials science. Understanding the competing underlying molecular interactions in self-assembly is always of interest to the academic scientific community and industry. …

Evaluation Of The Potential Of Automated Sem-Eds Analysis For The Discrimination Of Inorganic Soil Particles, Anna S. Duggar

Dissertations, Theses, and Capstone Projects

Soil, that complex mixture of minerals, organic particles, chemicals, and anthropogenic materials, is ubiquitous and easily transferred, which gives it forensic relevance. Forensic soil analysis has traditionally included the identification and comparison of both organic and inorganic components, the inorganic portion being most commonly examined by light microscopy and other instrumental techniques. Predominantly, the inorganic materials in soil are naturally-occurring minerals, contributed as grains from the surrounding bedrock, which gives a soil its regional character. That parent material then undergoes physical, chemical, and anthropogenic changes producing wide geographic variation within a single region. This variation forms the basis for potential …

Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles

Dissertations, Theses, and Capstone Projects

Hypersurface Photolithography (HP) is a printing method for fabricating structures and patterns composed of soft materials bound to solid surfaces and with ~1 micrometer resolution in the x, y, and z dimensions. This platform leverages benign, low intensity light to perform photochemical surface reactions with spatial and temporal control of irradiation, and, as a result, is particularly useful for patterning delicate organic and biological material. In particular, surface- initiated controlled radical polymerizations can be leveraged to create arbitrary polymer and block- copolymer brush patterns. Chapter 1 will review the advances in instrumentation architectures from our group that have made these …

Mechanically Transduced Immunosorbent Assay To Measure Protein-Protein Interactions, Christopher J. Petell, Kathyrn Randene, Michael Pappas, Diego Sandoval, Brian Dstrahl, Joseph S. Harrison, Joshua P. Steimel

College of the Pacific Faculty Articles

Measuring protein-protein interaction (PPI) affinities is fundamental to biochemistry. Yet, conventional methods rely upon the law of mass action and cannot measure many PPIs due to a scarcity of reagents and limitations in the measurable affinity ranges. Here, we present a novel technique that leverages the fundamental concept of friction to produce a mechanical signal that correlates to binding potential. The mechanically transduced immunosorbent (METRIS) assay utilizes rolling magnetic probes to measure PPI interaction affinities. METRIS measures the translational displacement of protein-coated particles on a protein-functionalized substrate. The translational displacement scales with the effective friction induced by a PPI, thus …

Differential Effects Of Polyphenols On Insulin Proteolysis By The Insulin-Degrading Enzyme, Qiuchen Zheng, Micheal T. Kebede, Bethany Lee, Claire A. Krasinski, Saadman Islam, Liliana A. Wurfl, Merc M. Kemeh, Valerie A. Ivancic, Charles E. Jakobsche, Donald E. Spratt, Noel Lazo

Chemistry

The insulin-degrading enzyme (IDE) possesses a strong ability to degrade insulin and Aβ42 that has been linked to the neurodegeneration in Alzheimer’s disease (AD). Given this, an attractive IDE-centric strategy for the development of therapeutics for AD is to boost IDE’s activity for the clearance of Aβ42 without offsetting insulin proteostasis. Recently, we showed that resveratrol enhances IDE’s activity toward Aβ42. In this work, we used a combination of chromatographic and spectroscopic techniques to investigate the effects of resveratrol on IDE’s activity toward insulin. For comparison, we also studied epigallocatechin-3-gallate (EGCG). Our results show that the two polyphenols affect the …

Synthesis, Characterization And Applications Of Europium Based Perovskite Oxide Nanoparticles, Nasim Farahmand

Dissertations, Theses, and Capstone Projects

The synthesis and characterization of nanocrystalline transition and rare-earth metal oxides have been studied widely over the past years. These materials possess unique physical, chemical, magnetic and dielectric properties which make them potential candidates for a wide range of applications such as electronics, energy storage and photocatalysis. There are a number of synthesis methods for preparing these materials, where most of them require stringent conditions such as high pressure and high temperature. However, in this study, a modified sol-gel synthesis has been used with a lower calcination temperature to make uniform nanocrystals of the transition/rare-earth metal oxide family. The focus …

Don't Sell Them Short, There's More To Bacterial Natural Products Than Antibiotics, Alison Clare Domzalski

Dissertations, Theses, and Capstone Projects

Recent genomic studies of microbiomes have revealed an overwhelming number of biosynthetic genes of unknown function. Most of these “cryptic” biosynthetic genes are not expressed in laboratory monocultures of individual microbes. Thus, there remains tremendous untapped potential for natural products discovery. Here we employ mixed microbial culture (MMC) as a simple yet powerful approach to awaken cryptic biosynthetic gene clusters. Our preliminary studies demonstrated that arrays of metabolites could be induced in MMCs upon environmental cues, such as surface adhesion. Using this system, we have screened, identified, and isolated bioactive bacterial metabolites, which were characterized structurally and biologically. Of the …

Electronic Structures And Spectroscopic Signatures Of Diiron Intermediates Generated By O2 Activation Of Nonheme Iron(Ii)–Thiolate Complexes, Danushka M. Ekanayake, Dao Pham, Andrew L. Probst, Joshua R. Miller, Cordina V. Popescu, Adam T. Fiedler

Chemistry Faculty Research and Publications

The activation of O₂ at thiolate–ligated iron(II) sites is essential to the function of numerous metalloenzymes and synthetic catalysts. Iron–thiolate bonds in the active sites of nonheme iron enzymes arise from either coordination of an endogenous cysteinate residue or binding of a deprotonated thiol-containing substrate. Examples of the latter include sulfoxide synthases, such as EgtB and OvoA, that utilize O₂ to catalyze tandem S–C bond formation and S-oxygenation steps in thiohistidine biosyntheses. We recently reported the preparation of two mononuclear nonheme iron–thiolate complexes (1 and 2) that serve as structural active-site models of substrate-bound EgtB …

Dissecting Monomer-Dimer Equilibrium Of An Rnase P Protein Provides Insight Into The Synergistic Flexibility Of 5’ Leader Pre-Trna Recognition, Danyun Zeng, Ainur Abzhanova, Benjamin P. Brown, Nicholas J. Reiter

Chemistry Faculty Research and Publications

Ribonuclease P (RNase P) is a universal RNA-protein endonuclease that catalyzes 5’ precursor-tRNA (ptRNA) processing. The RNase P RNA plays the catalytic role in ptRNA processing; however, the RNase P protein is required for catalysis in vivo and interacts with the 5’ leader sequence. A single P RNA and a P protein form the functional RNase P holoenzyme yet dimeric forms of bacterial RNase P can interact with non-tRNA substrates and influence bacterial cell growth. Oligomeric forms of the P protein can also occur in vitro and occlude the 5’ leader ptRNA binding interface, presenting a challenge in accurately defining …

Evaluation Of Wind Data Reliability By Using Logarithmic And Power Laws: A Case Study In Southern Iraq, Ahmed B. Khamees, Saif F. Yaseen, Khalid S. Heni, Mudar Ahmed Abdulsattar

Karbala International Journal of Modern Science

In this study, two sites were investigated in the southern region of Iraq: Ali AL-Gharbi and AL-Salman in Mesan and AL-Muthana provinces, respectively. A theoretical extrapolation between wind speed and height was carried out for both locations each month using the Logarithmic Law. Power Law was also applied to achieve calculations of wind shear coefficient (α) by using the actual data collected from the meteorological mast installed in each site at three levels of 10 m, 30 m, and 50 m, at an interval of ten minutes. To compare the effects of each law, two laws are employed.

Polystyrene Molecular Weight Determination Of Submicron Particles Shell, Airat Z. Sakhabutdinov, Safaa.M.R.H. Hussein, Alsu R. Ibragimova Ph.D., Vladimir Kuklin Ph.D., Maxim Petrovich Danilaev, L.Y. Zaharova

Karbala International Journal of Modern Science

The method of determination of the molecular weight of the polystyrene, which is formed as the shell on the surfaces of submicron aluminum oxide particles is considered in the paper. This method is based on the sedimentation of submicron particles, covered by polymer molecules, in a solvent for polystyrene. It is shown that the average polystyrene molecular weight is 39500±11250 amu, when the polymer shells on the surfaces of submicron particles (Al2O3) are formed by the vapor-phase method.

Adaptive Reconstruction Of The Heterogeneous Scan Line Etm+ Correction Technique, Heba Kh. Abbas, Salema S. Salman, Rash Awad Abtan, Anwar H. Al-Saleh, Ali A. Al-Zuky

Karbala International Journal of Modern Science

ETM+ is a land-imaging sensor with great and wide use in many fields, however, after May 2003, because of a technical defect in the sensor´s system scan line corrector SLC, it started giving images of earth containing black gap lines at a 22% rate. These gaps made the process of analyzing and extracting accurate information from these images difficult and complicated. Therefore, scientists have developed many techniques to remove the gap lines from all ETM+ band-images and complete the missing data. In this study, three different ETM+ time images with a 16-day interval between them were used to fill gap …