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2024

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Articles 961 - 990 of 1341

Full-Text Articles in Chemistry

Co2 Uptake By Microporous Carbon Aerogels Derived From Polybenzoxazine And Analogous All-Nitrogen Polybenzodiazine Aerogels, Vaibhav A. Edlabadkar, Rushi U. Soni, A. B.M.Shaheen Ud Doulah, Stephen Y. Owusu, Samuel Hackett, Joshua M. Bartels, Nicholas Leventis, Chariklia Sotiriou-Leventis Feb 2024

Co2 Uptake By Microporous Carbon Aerogels Derived From Polybenzoxazine And Analogous All-Nitrogen Polybenzodiazine Aerogels, Vaibhav A. Edlabadkar, Rushi U. Soni, A. B.M.Shaheen Ud Doulah, Stephen Y. Owusu, Samuel Hackett, Joshua M. Bartels, Nicholas Leventis, Chariklia Sotiriou-Leventis

Chemistry Faculty Research & Creative Works

The rapid rise of carbon dioxide in the atmosphere contributes to global warming and ocean acidification. Carbon capture is considered essential for keeping the atmospheric CO2 levels from rising further. This work addresses the question of whether nitrogen or oxygen lining of the surfaces of carbon-based CO2 absorbers is more efficient for CO2 capture. Polybenzodiazine (PBDAZ) aerogels are carbon-aerogel precursors that were prepared recently (2023) as all-nitrogen structural analogues to well-known polybenzoxazine (PBO) aerogels. However, owing to the fact that the carbonization chemistries of both PBO and PBDAZ aerogels require a prior oxidative aromatization step in air …


Machine Learning Model And Molecular Docking For Screening Medicinal Plants As Hiv-1 Reverse Transcriptase Inhibitors, Muthia Rahayu Iresha, Firdayani Firdayani, Agam Wira Sani, Nihayatul Karimah, Shelvi Listiana, Irfansyah Yudhi Tanasa, Arief Sartono, Ayu Masyita Feb 2024

Machine Learning Model And Molecular Docking For Screening Medicinal Plants As Hiv-1 Reverse Transcriptase Inhibitors, Muthia Rahayu Iresha, Firdayani Firdayani, Agam Wira Sani, Nihayatul Karimah, Shelvi Listiana, Irfansyah Yudhi Tanasa, Arief Sartono, Ayu Masyita

Karbala International Journal of Modern Science

The human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) plays a significant role in viral replication and is one of the targets for anti-HIV. However, a mutation in viral strains rapidly developed the resistance of the com-pounds to the protein, reducing the effectiveness of the inhibitors. This work seeks to utilize machine learning-based quantitative structure-activity relationship (QSAR) analysis in combination with molecular docking simulations to forecast the presence of active compounds derived from medicinal plants. Specifically, the objective is to identify com-pounds that have the potential to operate as inhibitors of HIV-1 reverse transcriptase (RT), encompassing both wild-type and …


Historical Analysis Of Urban Dust Generated By The Great Salt Lake Playa, Callum Flowerday, Jaron C. Hansen, Rebekah Stanley, Kaitlyn Brewster Feb 2024

Historical Analysis Of Urban Dust Generated By The Great Salt Lake Playa, Callum Flowerday, Jaron C. Hansen, Rebekah Stanley, Kaitlyn Brewster

ScholarsArchive Data

Historical PM10 filters, provided by the Utah Division of Air Quality, were analyzed for elemental composition of various metals. This was done using ICP-MS.

Also included, EPA PM10 historical data and bathymetry data provided by the Utah USGS.


Pisa Printing Microneedles With Controllable Aqueous Dissolution Kinetics, Aaron Priester, Jimmy Yeng, Yuwei Zhang, Krista Hilmas, Risheng Wang, Anthony J. Convertine Feb 2024

Pisa Printing Microneedles With Controllable Aqueous Dissolution Kinetics, Aaron Priester, Jimmy Yeng, Yuwei Zhang, Krista Hilmas, Risheng Wang, Anthony J. Convertine

Chemistry Faculty Research & Creative Works

This study focused on the development of high-resolution polymeric structures using polymer-induced self-assembly (PISA) printing with commercially available digital light-processing (DLP) printers. Significantly, soluble solids could be 3D-printed using this methodology with controllable aqueous dissolution rates. This was achieved using a highly branched macrochain transfer agent (macro-CTA) containing multiple covalently attached CTA groups. In this work, the use of acrylamide as the self-assembling monomer in isopropyl alcohol was explored with the addition of N-(butoxymethyl)acrylamide to modulate the aqueous dissolution kinetics. PISA-printed microneedles were observed to have feature sizes as small as 27 μm, which was close to the resolution limit …


An Observational Framework For Constructing Ozone Isopleths From Long-Term Monitoring Data: Demonstration In Salt Lake City, Utah, Callum Flowerday, Isaac Sudweeks, Brad Adams, Jaron C. Hansen Feb 2024

An Observational Framework For Constructing Ozone Isopleths From Long-Term Monitoring Data: Demonstration In Salt Lake City, Utah, Callum Flowerday, Isaac Sudweeks, Brad Adams, Jaron C. Hansen

ScholarsArchive Data

EPA quality assured data, collected by the Utah Division of Air Quality, was used for this analysis.


Unimer Suppression Enables Supersaturated Homopolymer Swollen Micelles With Long-Term Stability After Glassy Entrapment, Eric R. Williams, Christian X. Ruff, Morgan Stefik Feb 2024

Unimer Suppression Enables Supersaturated Homopolymer Swollen Micelles With Long-Term Stability After Glassy Entrapment, Eric R. Williams, Christian X. Ruff, Morgan Stefik

Faculty Publications

Micelle sizes are critical for a range of applications where the simple ability to adjust and lock in specific stable sizes has remained largely elusive. While micelle swelling agents are well-known, their dynamic re-equilibration in solution implies limited stability. Here, a non-equilibrium processing sequence is studied where supersaturated homopolymer swelling is combined with glassy-core (“persistent”) micelles. This path-dependent process was found to sensitively depend on unimer concentration as revealed by DLS, SAXS, and TEM analysis. Here, lower-selectivity solvent combinations led to the formation of unimer-homopolymer aggregates and eventual precipitation, reminiscent of anomalous micellization. In contrast, higher-selectivity solvents enabled supersaturated homopolymer …


Determining The Surface PKA Of Perfluorooctanoic Acid, Lila J. Musegades, Owen P. Curtin, Jenée D. Cyran Feb 2024

Determining The Surface PKA Of Perfluorooctanoic Acid, Lila J. Musegades, Owen P. Curtin, Jenée D. Cyran

Chemistry and Biochemistry Faculty Publications and Presentations

Perfluorooctanoic acid (PFOA) is an environmentally prevalent and persistent organic pollutant with toxic and bioaccumulative properties. Despite the known importance of perfluorinated pollutants in the global environment, molecular-level details of the physicochemical behavior of PFOA on aqueous interfaces remain poorly understood. Here, we utilized two surface-specific techniques, vibrational sum frequency generation spectroscopy (SFG) and surface tensiometry, to investigate the pH-induced structural changes of PFOA and octanoic acid (OA) and determined the apparent pKa at the air–water surface. The SFG spectra and surface activity model were investigated over a wide range of pHs. With the surface tension measurements, the …


Unimer Suppression Enables Supersaturated Homopolymer Swollen Micelles With Long-Term Stability After Glassy Entrapment, Eric R. Williams, Christian X. Ruff, Morgan Stefik Feb 2024

Unimer Suppression Enables Supersaturated Homopolymer Swollen Micelles With Long-Term Stability After Glassy Entrapment, Eric R. Williams, Christian X. Ruff, Morgan Stefik

Faculty Publications

Micelle sizes are critical for a range of applications where the simple ability to adjust and lock in specific stable sizes has remained largely elusive. While micelle swelling agents are well-known, their dynamic re-equilibration in solution implies limited stability. Here, a non-equilibrium processing sequence is studied where supersaturated homopolymer swelling is combined with glassy-core (“persistent”) micelles. This path-dependent process was found to sensitively depend on unimer concentration as revealed by DLS, SAXS, and TEM analysis. Here, lower-selectivity solvent combinations led to the formation of unimer-homopolymer aggregates and eventual precipitation, reminiscent of anomalous micellization. In contrast, higher-selectivity solvents enabled supersaturated homopolymer …


Sulfate Enhances The Adsorption And Retention Of Cu(Ii) And Zn(Ii) To Dispersed And Aggregated Iron Oxyhydroxide Nanoparticles, Emma M. Kocik, Abigail Kim, Miranda L. Aiken, Lauren Smith, Christopher S. Kim Feb 2024

Sulfate Enhances The Adsorption And Retention Of Cu(Ii) And Zn(Ii) To Dispersed And Aggregated Iron Oxyhydroxide Nanoparticles, Emma M. Kocik, Abigail Kim, Miranda L. Aiken, Lauren Smith, Christopher S. Kim

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The adsorption and retention of metal ions to nanoscale iron (hydr)oxides in aqueous systems is significantly influenced by prevailing environmental conditions. We examined the influence of sulfate, the second most common anion in seawater that is present in many other natural aquatic systems, on the adsorption and retention of Cu(II) and Zn(II) to synthetic iron oxyhydroxide nanoparticles (NPs) and their aggregates. Batch uptake experiments with monodisperse NPs and NPs aggregated by changes in pH, ionic strength, and temperature were conducted over sulfate concentrations ranging from 0 to 0.30 M. The introduction of 0.03 M sulfate significantly increased the initial adsorption …


Computational Study Of Binding Of Oseltamivir To Neuraminidase Mutants Of Influenza A Virus, Muhammad Arba, Sri Wahyuli, Setyanto Tri Wahyudi, Amir Karton, Chun Wu Feb 2024

Computational Study Of Binding Of Oseltamivir To Neuraminidase Mutants Of Influenza A Virus, Muhammad Arba, Sri Wahyuli, Setyanto Tri Wahyudi, Amir Karton, Chun Wu

College of Science & Mathematics Departmental Research

Oseltamivir (OTV), which targets the neuraminidase (NA) of Influenza A virus (IAV), has been reported to develop resistance. Here, we performed a computational study on the binding modes of OTV in the wild-type and popular mutants of IAV NA (E119A, E119D, E119G, H274Y, I117T, I117V, I117V-E119A, K150N, N294S, R292K, V116A, and Y252H). The Arg118, Glu119, Asp151, Arg152, Glu276, Arg292, and Arg371 were identified as crucial interacting residues with the drug. The energy decomposition analysis showed that with few exceptions, the dispersion interaction is the dominant interaction, followed by the charge-transfer and polarization interactions. The affinities for OTV were greatly reduced …


Maximizing Charge Dynamics In Znin2s4/Cn Van Der Waals Heterojunction For Optimal Hydrogen Production From Photoreforming Of Glucose, Jinqiang Zhang, Xinyuan Xu, Lei Shi, Huayang Zhang, Shaobin Wang, Hongqi Sun Feb 2024

Maximizing Charge Dynamics In Znin2s4/Cn Van Der Waals Heterojunction For Optimal Hydrogen Production From Photoreforming Of Glucose, Jinqiang Zhang, Xinyuan Xu, Lei Shi, Huayang Zhang, Shaobin Wang, Hongqi Sun

Research outputs 2022 to 2026

Biomass photoreforming stands out as a promising avenue for green hydrogen, leveraging solar energy for the generation and transformation of clean and renewable energy resources. The pursuit of efficient photocatalysts is motivated by the unsatisfied hydrogen evolution performance arising from the complex and stubborn structure of biomass. Herein, we loaded 2-dimensional (2D) ZnIn2S4 onto 2D carbon nitride nanosheets, resulting in the formation of Van der Waals (VDW) heterojunctions (ZIS/CN). Band structure and morphology of CN were rationally tailored through precursor engineering to effectively magnify interfacial internal electric field and minimize diffusion pathway within the VDW heterostructure, realizing optimal charge dynamics …


Unusual Catalytic Strategy By Non-Heme Fe(Ii)/2-Oxoglutarate-Dependent Aspartyl Hydroxylase Asph, Anandhu Krishnan, Sodiq Waheed, Ann Varghese, Fathima Hameed Cherilakkudy, Christopher J. Schofield, Tatyana G. Karabencheva-Christova Feb 2024

Unusual Catalytic Strategy By Non-Heme Fe(Ii)/2-Oxoglutarate-Dependent Aspartyl Hydroxylase Asph, Anandhu Krishnan, Sodiq Waheed, Ann Varghese, Fathima Hameed Cherilakkudy, Christopher J. Schofield, Tatyana G. Karabencheva-Christova

Michigan Tech Publications

Biocatalytic C-H oxidation reactions are of important synthetic utility, provide a sustainable route for selective synthesis of important organic molecules, and are an integral part of fundamental cell processes. The multidomain non-heme Fe(ii)/2-oxoglutarate (2OG) dependent oxygenase AspH catalyzes stereoselective (3R)-hydroxylation of aspartyl- and asparaginyl-residues. Unusually, compared to other 2OG hydroxylases, crystallography has shown that AspH lacks the carboxylate residue of the characteristic two-His-one-Asp/Glu Fe-binding triad. Instead, AspH has a water molecule that coordinates Fe(ii) in the coordination position usually occupied by the Asp/Glu carboxylate. Molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) studies reveal that the iron coordinating water is …


Multi-Agent System For Portfolio Profit Optimization For Future Stock Trading, Usha Devi, Mohan R Feb 2024

Multi-Agent System For Portfolio Profit Optimization For Future Stock Trading, Usha Devi, Mohan R

Karbala International Journal of Modern Science

Stock trading highly contributes to the economic growth of the country. The stock trading objective is to earn profits with buy/sell/hold decisions on the set of stocks in the portfolio. The portfolio optimization problem is finding the decision sequence that leads to higher profit and lower risk. Portfolio optimization is challenging due to complex price history patterns and an uncertain environment. Incorrect decisions in stock trading lead to massive losses. The proposed Multi-Agent System for Portfolio Profit Optimization (MASPPO) aims to optimize trading profit and reduce risk with accurate predictions. The proposed model integrates the Fuzzy c-means with the Deep …


Use Of Dft Calculations As A Tool For Designing New Solvatochromic Probes For Biological Applications, Cynthia M. Dupureur Feb 2024

Use Of Dft Calculations As A Tool For Designing New Solvatochromic Probes For Biological Applications, Cynthia M. Dupureur

Educator Preparation & Leadership Faculty Works

The intramolecular charge transfer behavior of push–pull dyes is the origin of their sensitivity to environment. Such compounds are of interest as probes for bioimaging and as biosensors to monitor cellular dynamics and molecular interactions. Those that are solvatochromic are of particular interest in studies of lipid dynamics and heterogeneity. The development of new solvatochromic probes has been driven largely by the need to tune desirable properties such as solubility, emission wavelength, or the targeting of a particular cellular structure. DFT calculations are often used to characterize these dyes. However, if a correlation between computed (dipole moment) and experimentally measured …


Spontaneous Transfer Of Small Peripheral Peptides Between Supported Lipid Bilayer And Giant Unilamellar Vesicles, Emanuela Efodili, Ashlynn Knight, Maryem Mirza, Cedric Briones, Il Hyung Lee Feb 2024

Spontaneous Transfer Of Small Peripheral Peptides Between Supported Lipid Bilayer And Giant Unilamellar Vesicles, Emanuela Efodili, Ashlynn Knight, Maryem Mirza, Cedric Briones, Il Hyung Lee

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Vesicular trafficking facilitates material transport between membrane-bound organelles. Membrane protein cargos are trafficked for relocation, recycling, and degradation during various physiological processes. In vitro fusion studies utilized synthetic lipid membranes to study the molecular mechanisms of vesicular trafficking and to develop synthetic materials mimicking the biological membrane trafficking. Various fusogenic conditions which can induce vesicular fusion have been used to establish synthetic systems that can mimic biological systems. Despite these efforts, the mechanisms underlying vesicular trafficking of membrane proteins remain limited and robust in vitro methods that can construct synthetic trafficking systems for membrane proteins between large membranes (>1 …


Simple Sars-Cov-2 Concentration Methods For Wastewater Surveillance In Low Resource Settings, Mohammad Dehghan Banadaki, Soroosh Torabi, Alexus Lori Rockward, William Strike, Ann Noble, James W. Keck, Scott M. Berry Feb 2024

Simple Sars-Cov-2 Concentration Methods For Wastewater Surveillance In Low Resource Settings, Mohammad Dehghan Banadaki, Soroosh Torabi, Alexus Lori Rockward, William Strike, Ann Noble, James W. Keck, Scott M. Berry

UK CARES Faculty Publications

Wastewater-based epidemiology (WBE) measures pathogens in wastewater to monitor infectious disease prevalence in communities. Due to the high dilution of pathogens in sewage, a concentration method is often required to achieve reliable biomarker signals. However, most of the current concentration methods rely on expensive equipment and labor-intensive processes, which limits the application of WBE in low-resource settings. Here, we compared the performance of four inexpensive and simple concentration methods to detect SARS-CoV-2 in wastewater samples: Solid Fraction, Porcine Gastric Mucin-conjugated Magnetic Beads, Calcium Flocculation- Citrate Dissolution (CFCD), and Nanotrap® Magnetic Beads (NMBs). The NMBs and CFCD methods yielded the highest …


Screen-Printed Sensors Modified With Nafion And Mesoporous Carbon For Electrochemical Detection Of Lead In Blood, Elena Boselli, Zhizhen Wu, Erin N. Haynes, Ian Papautsky Feb 2024

Screen-Printed Sensors Modified With Nafion And Mesoporous Carbon For Electrochemical Detection Of Lead In Blood, Elena Boselli, Zhizhen Wu, Erin N. Haynes, Ian Papautsky

UK CARES Faculty Publications

Lead (Pb) has long been acknowledged as a systemic toxicant, with pronounced health impacts observed even at low exposure levels, particularly in children. Adverse effects include diminished cognitive function, altered behavior, and developmental delays. Consequently, it is imperative to conduct regular monitoring of Blood Lead Levels (BLLs). In this work, we report on an electrochemical sensor based on screen-printed carbon electrode (SPCE) coated with Nafion and mesoporous carbon (MC). The sensor system uses simple sample preparation (acidification and dilution of whole blood), minimal sample volume (a few blood drops, 200 μl), and swift time-to-results (1 h). A limit of quantitation …


An Itpa Enzyme With Improved Substrate Selectivity, Nicholas E. Burgis, Kandise Vanwormer, Devin Robbins, Jonathan Smith Feb 2024

An Itpa Enzyme With Improved Substrate Selectivity, Nicholas E. Burgis, Kandise Vanwormer, Devin Robbins, Jonathan Smith

Chemistry and Biochemistry Faculty Publications

Recent clinical data have identified infant patients with lethal ITPA deficiencies. ITPA is known to modulate ITP concentrations in cells and has a critical function in neural development which is not understood. Polymorphism of the ITPA gene affects outcomes for both ribavirin and thiopurine based therapies and nearly one third of the human population is thought to harbor ITPA polymorphism. In a previous site-directed mutagenesis alanine screen of the ITPA substrate selectivity pocket, we identified the ITPA mutant, E22A, as a gain-of function mutant with enhanced ITP hydrolysis activity. Here we report a rational enzyme engineering experiment to investigate the …


Vaccine Immunogenicity Versus Gastrointestinal Microbiome Status: Implications For Poultry Production, Chrysta N. Beck, Jiangchao Zhao, Gisela F. Erf Feb 2024

Vaccine Immunogenicity Versus Gastrointestinal Microbiome Status: Implications For Poultry Production, Chrysta N. Beck, Jiangchao Zhao, Gisela F. Erf

Poultry Science Faculty Publications and Presentations

At the turn of the 21st century, the importance of maintaining a balanced microbiome was brought to the forefront of the microbiology, immunology, and physiology research fields. Exploring the complex interactions between vaccine administration, mucosal microbiome, oral tolerance, and enteric inflammation in health and disease is challenging since environmental factors (such as diet and sanitation) have major influences on gut microbiota composition. High enteric pathogen load has been shown to contribute to dampened cell-mediated and humoral immune responses to vaccines in human case studies, either through elevated enteric inflammation or increased tolerance to environmental microbes. Although antibiotic and probiotic interventions …


College Of Natural Sciences 2023 Year-End Publication, College Of Natural Sciences Feb 2024

College Of Natural Sciences 2023 Year-End Publication, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message
Page 3 Department Highlights
Page 4 One Day for State
Page 5 Noble Prize Winner Speaks on Campus
Page 6-7 Faculty Excellence
Page 8-9 Student Excellence
Page 10 Outreach Program
Page 10 Events and Traditions
Page 11 Connections Abroad
Page 12 Student Spotlight
Page 13 Alumni Spotlight
Page 14 First Ever Drone Day
Page 15 Grand Opening of POET Bioproducts Center
Page 16 Work Anniversaries


Amperometric Bio-Sensing Of Lactate And Oxygen Concurrently With Local Field Potentials During Status Epilepticus, Eliana Fernandes, Ana Ledo, Greg A. Gerhardt, Rui M. Barbosa Feb 2024

Amperometric Bio-Sensing Of Lactate And Oxygen Concurrently With Local Field Potentials During Status Epilepticus, Eliana Fernandes, Ana Ledo, Greg A. Gerhardt, Rui M. Barbosa

Neurology Faculty Publications

Epilepsy is a prevalent neurological disorder with a complex pathogenesis and unpredictable nature, presenting limited treatment options in >30 % of affected individuals. Neurometabolic abnormalities have been observed in epilepsy patients, suggesting a disruption in the coupling between neural activity and energy metabolism in the brain. In this study, we employed amperometric biosensors based on a modified carbon fiber microelectrode platform to directly and continuously measure lactate and oxygen dynamics in the brain extracellular space. These biosensors demonstrated high sensitivity, selectivity, and rapid response time, enabling in vivo measurements with high temporal and spatial resolution. In vivo recordings in the …


Evaluating The Reliability And Accuracy Of Alchemical Binding Free Energy Methods And Calculations, Fnu Sheenam Feb 2024

Evaluating The Reliability And Accuracy Of Alchemical Binding Free Energy Methods And Calculations, Fnu Sheenam

Dissertations, Theses, and Capstone Projects

Molecular recognition plays a crucial role in various biological processes, such as enzymatic reactions, signal transduction, and genetic information processing. Investigating how proteins selectively bind to their partners is an active research area, but there is a lack of experimental details on protein structures and interactions in molecular complexes. Computational techniques based on macromolecular structures offer a way to predict protein-ligand interactions and explore their recognition mechanisms. Estimating binding affinities, particularly through alchemical binding free energy calculations, has become valuable in supporting drug discovery. This work introduces new methodologies, utilizing the Alchemical Transfer Method, to address issues like poor convergence …


Rational Design Of Peptide-Based Materials Informed By Multiscale Molecular Dynamics Simulations, Dhwanit Rahul Dave Feb 2024

Rational Design Of Peptide-Based Materials Informed By Multiscale Molecular Dynamics Simulations, Dhwanit Rahul Dave

Dissertations, Theses, and Capstone Projects

The challenge of establishing a sustainable and circular economy for materials in medicine and technology necessitates bioinspired design. Nature's intricate machinery, forged through evolution, relies on a finite set of biomolecular building blocks with through-bond and through-space interactions. Repurposing these molecular building blocks requires a seamless integration of computational modeling, design, and experimental validation. The tools and concepts developed in this thesis pioneer new directions in peptide-materials design, grounded in fundamental principles of physical chemistry. We present a synergistic approach that integrates experimental designs and computational methods, specifically molecular dynamics simulations, to gain in-depth molecular insights crucial for advancing the …


Synthesis And Characterization Of Donor-Acceptor Fluorescent Conjugated Polymers By Acyclic Diene Metathesis (Admet) And Suzuki Polycondensation (Spc), Hamid Ardolic Jr. Feb 2024

Synthesis And Characterization Of Donor-Acceptor Fluorescent Conjugated Polymers By Acyclic Diene Metathesis (Admet) And Suzuki Polycondensation (Spc), Hamid Ardolic Jr.

Dissertations, Theses, and Capstone Projects

Conjugated polymers are useful in a wide variety of applications including production of Light Emitting Diodes (LEDs), Field Effect Transistors (FETs) and organic photovoltaics. Our work in the lab focuses on the development of materials for use in Polymer Solar Cells (PSCs) using various electron donating and electron accepting units to individually tune the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) respectively and produce a small but controlled band gap. This is accomplished through the synthesis of several precursors and their subsequent polymerization using Acyclic Diene Metathesis (ADMET) and Suzuki Polycondensation (SPC). Moderately strong electron donors, …


Stereospecific Cross-Coupling Reactions Of Vinyl Triflates And An Investigation Of The Synthesis And Reactivity Of Activated Alkyltricyclohexylstannanes, Pejman Ghaemimohammadi Feb 2024

Stereospecific Cross-Coupling Reactions Of Vinyl Triflates And An Investigation Of The Synthesis And Reactivity Of Activated Alkyltricyclohexylstannanes, Pejman Ghaemimohammadi

Dissertations, Theses, and Capstone Projects

Organic chemistry exists in all aspects of everyday life from polymers to pharmaceutics. Formation of carbon-carbon bonds is essential for the synthesis of complex organic compounds. This goal can be achieved by using transition metal catalysts. Second-row transition metals such as Pd, Pt, Rh, and Ir have shown remarkable efficacy in these reactions. Metal-catalyzed cross-coupling reactions form carbon-carbon bonds between electrophiles and nucleophiles using transition metal catalysts. Pd is mainly used in this reaction.

Transition metal-catalyzed cross-coupling reactions that form a bond between two C(sp2) carbons have been widely studied over the past decades. C(sp2)-C(sp3 …


Biomolecular Crystals As Functional Materials, Fahmeed Khan Sheehan Feb 2024

Biomolecular Crystals As Functional Materials, Fahmeed Khan Sheehan

Dissertations, Theses, and Capstone Projects

The field of supramolecular chemistry has undergone significant evolution over the last few decades, progressing from fundamental studies of self-assembling systems to the rational design of functional materials with exceptional properties. Among these materials, short peptides have emerged as a chemically simple yet highly versatile class of biomimetic compounds. Initially, short peptides were used as model systems to understand larger protein interactions. As the field progressed, short peptides were found to have exceptional functionality, and are now explored as functional nanomaterials for diverse applications. In many cases, short peptide materials have displayed properties not found in biology, in some cases …


Studies Of Oxidopyrylium Ylide Dimers And Their Utility In The Synthesis Of Densely Functionalized Troponoids, Daniel V. Schiavone Feb 2024

Studies Of Oxidopyrylium Ylide Dimers And Their Utility In The Synthesis Of Densely Functionalized Troponoids, Daniel V. Schiavone

Dissertations, Theses, and Capstone Projects

Herein, we describe our efforts to investigate mechanistic considerations of oxidopyrylium ylides and their use in cycloadditions to form complex bicyclic structures and the advancement of these cycloadducts to the synthesis of densely functionalized tropolones. This work also describes applications of tropolones as biologically relevant structures and dynamic fluorophores.

In Chapter 1, we expand upon previous studies done in the Murelli Lab describing the ability of 3-hydroxy-4-pyrone derived oxidopyrylium dimers to revert back to ylides in situ and as result can be used as a clean oxidopyrylium ylide source in accessing oxabicyclic compounds. Intermolecular cycloadditions of these ylides can be …


Accessing Reactive Metal Hydrides Through Designed Heterometallic Bridges, Fernando Gonzalez, Edgardo De Leon, Manar M. Shoshani Feb 2024

Accessing Reactive Metal Hydrides Through Designed Heterometallic Bridges, Fernando Gonzalez, Edgardo De Leon, Manar M. Shoshani

School of Integrative Biological & Chemical Sciences Faculty Publications

A methodology to access reactive hydride moieties is highly desirable, yet limited. Multimetallic hydride fragments are notable for their heightened reactivity and catalysis, but deliberate access to these species is lacking. In this highlight, we discuss recent developments by our group in the design of a new heterometallic complex that invokes an architecture designed to provide modular access to reactive hydride moieties by leveraging metal hydrides in combination with pendent donors to a model heterotrimetallic Ni–(Al–H)2 complex. An amplification of insertion-based reactivity has been examined in the hydrofunctionalization of quinolines, and our complex substantially outperformed the parent aluminum hydride LAlH …


New Discoveries On Protein Recruitment And Regulation During The Early Stages Of The Dna Damage Response Pathways, Kelly Waters, Donald E. Spratt Feb 2024

New Discoveries On Protein Recruitment And Regulation During The Early Stages Of The Dna Damage Response Pathways, Kelly Waters, Donald E. Spratt

Chemistry

Maintaining genomic stability and properly repairing damaged DNA is essential to staying healthy and preserving cellular homeostasis. The five major pathways involved in repairing eukaryotic DNA include base excision repair (BER), nucleotide excision repair (NER), mismatch repair (MMR), non-homologous end joining (NHEJ), and homologous recombination (HR). When these pathways do not properly repair damaged DNA, genomic stability is compromised and can contribute to diseases such as cancer. It is essential that the causes of DNA damage and the consequent repair pathways are fully understood, yet the initial recruitment and regulation of DNA damage response proteins remains unclear. In this review, …


The Effect Of Variation Of N-Substituents On Oxidopyridinium Ions In (4+3) Cycloadditions, Zahria Patrick, Madison Clark Jan 2024

The Effect Of Variation Of N-Substituents On Oxidopyridinium Ions In (4+3) Cycloadditions, Zahria Patrick, Madison Clark

Undergraduate Research Symposium

The aim of this research project is to expand the scope of 4 + 3 cycloadduct chemistry by varying functional groups attached to the prerequisite oxidopyridinium ion for each respective cycloadduct product. While N-substitution of the pyridinium precursor is known to proceed smoothly if alkylated by a lone methyl group, we evaluated the effect a larger alkyl group would have on the overall yield of the 4 + 3 cycloadduct product.

Isobutyl triflate, generated from the known reaction between isobutyl alcohol and triflic anhydride, was reacted with ethyl 5-hydroxy-nicotinate to generate the respective N-isobutyl oxidopyridinium ion in quantitative …