Chemistry Commons^™

Differential Modulation Of Sk Channel Subtypes By Phosphorylation, Young-Woo Nam, Dezhi Kong, Dong Wang, Razan Orfali, Rinzhin T. Sherpa, Jennifer Totonchy, Surya M. Nauli, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca²⁺-activated K⁺ (SK) channels are voltage-independent and are activated by Ca²⁺ binding to the calmodulin constitutively associated with the channels. Both the pore-forming subunits and the associated calmodulin are subject to phosphorylation. Here, we investigated the modulation of different SK channel subtypes by phosphorylation, using the cultured endothelial cells as a tool. We report that casein kinase 2 (CK2) negatively modulates the apparent Ca²⁺ sensitivity of SK1 and IK channel subtypes by more than 5-fold, whereas the apparent Ca²⁺ sensitivity of the SK3 and SK2 subtypes is only reduced by ∼2-fold, when heterologously …

Modes Of Transmission Of Severe Acute Respiratory Syndrome-Coronavirus-2 (Sars-Cov-2) And Factors Influencing On The Airborne Transmission: A Review, Mahdieh Delikhoon, Marcelo I. Guzman, Ramin Nabizadeh, Abbas Norouzian Baghani

Chemistry Faculty Publications

The multiple modes of SARS-CoV-2 transmission including airborne, droplet, contact, and fecal–oral transmissions that cause coronavirus disease 2019 (COVID-19) contribute to a public threat to the lives of people worldwide. Herein, different databases are reviewed to evaluate modes of transmission of SARS-CoV-2 and study the effects of negative pressure ventilation, air conditioning system, and related protection approaches of this virus. Droplet transmission was commonly reported to occur in particles with diameter >5 µm that can quickly settle gravitationally on surfaces (1–2 m). Instead, fine and ultrafine particles (airborne transmission) can stay suspended for an extended period of time (≥2 h) …

Numerical Reconstruction Of Spalled Particle Trajectories In An Arc-Jet Environment, Raghava S. C. Davuluri, Sean C. C. Bailey, Kaveh A. Tagavi, Alexandre Martin

Mechanical Engineering Faculty Publications

To evaluate the effects of spallation on ablative material, it is necessary to evaluate the mass loss. To do so, a Lagrangian particle trajectory code is used to reconstruct trajectories that match the experimental data for all kinematic parameters. The results from spallation experiments conducted at the NASA HYMETS facility over a wedge sample were used. A data-driven adaptive methodology was used to adapts the ejection parameters until the numerical trajectory matches the experimental data. The preliminary reconstruction results show that the size of the particles seemed to be correlated with the location of the ejection event. The size of …

From Ideas To Items: A Primer On The Development Of Ordered Multiple-Choice Items For Investigating The Progression Of Learning In Higher Education Stem, Katherine Lazenby, Morgan E. Balabanoff, Nicole M. Becker, Alena Moon, Jack Barbera

Chemistry Faculty Publications and Presentations

Identifying effective methods of assessment and developing robust assessments are key areas of research in chemistry education. This research is needed to evaluate instructional innovations and curricular reform. In this primer, we advocate for the use of a type of assessment, ordered multiple-choice (OMC), across postsecondary chemistry. OMC assessments are grounded in a developmental perspective, which treats students’ knowledge as developing in sophistication over time. This is in contrast to a dichotomous perspective, which asserts that students’ knowledge is either aligned or misaligned with scientifically accepted knowledge. By drawing on a developmental perspective, OMC assessments offer insights into student understanding …

N-Type Charge Transport In Heavily P-Doped Polymers, Zhiming Liang, Hyun Ho Choi, Xuyi Luo, Tuo Liu, Ashkan Abtahi, Uma Shantini Ramasamy, J. Andrew Hitron, Kyle N. Baustert, Jacob L. Hempel, Alex M. Boehm, Armin Ansary, Douglas R. Strachan, Jianguo Mei, Chad Risko, Vitaly Podzorov, Kenneth R. Graham

Chemistry Faculty Publications

It is commonly assumed that charge-carrier transport in doped π-conjugated polymers is dominated by one type of charge carrier, either holes or electrons, as determined by the chemistry of the dopant. Here, through Seebeck coefficient and Hall effect measurements, we show that mobile electrons contribute substantially to charge-carrier transport in π-conjugated polymers that are heavily p-doped with strong electron acceptors. Specifically, the Seebeck coefficient of several p-doped polymers changes sign from positive to negative as the concentration of the oxidizing agents FeCl3 or NOBF4 increase, and Hall effect measurements for the same p-doped polymers reveal that …

Structural Insights Into Ankyrin Repeat-Containing Proteins And Their Influence In Ubiquitylation, Emma I. Kane, Donald E. Spratt

Chemistry

Ankyrin repeat (AR) domains are considered the most abundant repeat motif found in eukaryotic proteins. AR domains are predominantly known to mediate specific protein–protein interactions (PPIs) without necessarily recognizing specific primary sequences, nor requiring strict conformity within its own primary sequence. This promiscuity allows for one AR domain to recognize and bind to a variety of intracellular substrates, suggesting that AR-containing proteins may be involved in a wide array of functions. Many AR-containing proteins serve a critical role in biological processes including the ubiquitylation signaling pathway (USP). There is also strong evidence that AR-containing protein malfunction are associated with several …

Gene Alteration In Zebrafish Exposed To A Mixture Of Substances Of Abuse☆, Bikram Subedi, Sydni Anderson, Tara L. Croft, Eric C. Rouchka, Mei Zhang, Dena Weinberger

Faculty & Staff Research and Creative Activity

A recent surge in the use and abuse of diverse prescribed psychotic and illicit drugs necessitates the surveillance of drug residues in source water and the associated ecological impacts of chronic exposure to the aquatic organism. Thirty-six psychotic and illicit drug residues were determined in discharged wastewater from two centralized municipal wastewater treatment facilities and two wastewater receiving creeks for seven consecutive days in Kentucky. Zebrafish (Danio rerio) larvae were exposed to the environmental relevant mixtures of all drug residues, all illicit drugs, and all prescribed psychotic drugs. The extracted RNA from fish homogenates was sequenced, and differentially …

Why Are Glycines 31, 33, And 35 Highly Conserved In All Fluorescent Proteins?, Justin Nwafor

Chemistry Honors Papers

Since the discovery of the Green Fluorescent Protein (GFP), fluorescent proteins (FPs) have been used as biomarkers to monitor biological phenomena across many scientific disciplines. All naturally-occurring FPs consist of an 11-stranded β-barrel with a non-canonical α-helix, which contains the chromophore, running through the central axis of the protein. Glycines 31, 33, and 35 are highly conserved across the fluorescent proteins found in the PDB. These three residues are of interest due to them all being located in the second strand of the β-barrel, but having no direct involvement in chromophore formation. This led to a presumption that the glycines …

System-Level Approaches For Intensifying The Co2 Electrolysis Process: From Reaction Chemistry To Process Development, Saket S. Bhargava

Link Foundation Energy Fellowship Reports

Electrochemical reduction of CO2 (CO2RR) is a promising alternative for producing carbon-based value-added chemicals such as carbon monoxide, ethylene, and ethanol that are currently produced using thermochemical fossil fuel-based production methods.1 Despite research breakthroughs, significant improvements are still needed in terms of activities (partial current densities – pCDs), selectivities (Faradaic efficiencies – FEs), and full cell energy efficiencies (EEs) before the CO2 electrolysis process can be employed at industrial scales in an economically feasible and carbon-neutral manner.

Design And Synthesis Of Non-Xanthone Structural Analogs Of Α-Mangostin, Maryam Foroozmehr

Theses and Dissertations

α-Mangostin belongs to a class of polyphenolic compounds called xanthones. The potential pharmacological effects such as anti-bacterial and anti-cancer effects of α-mangostin have made it an important natural product for medicinal chemistry evaluation. During this thesis research, we have designed and synthesized a series of non-xanthone analogs of α-mangostin for medicinal chemistry evaluation. A commercially available starting material, methyl-4-methoxysalicylate was used to synthesize these non-xanthone analogs. The analogs were designed as more flexible derivatives compared to the tricyclic motif within α-mangostin yet retain the hydroxybenzoate scaffold. Through a one-pot chemical synthesis, with relatively high yield (70%), we prepared eight different …

Forensic Genealogy: A Tool In Dna Analysis, Samantha Olsen

Undergraduate Honors College Theses 2016-

DNA is the basic unit of which differentiates one individual to the next. Short Tandem Repeats and Single Nucleotide Polymorphisms are two locations of DNA that have been the most successful in DNA analysis. Unique DNA profiles can be created so that interpretations can be made about the individual who contributed to the DNA sample. Systems like STRmix are currently being employed to give unbiased assumptions about the DNA profiles. There are several different statistical approaches in assigning probabilities to DNA evidence, likelihood ratio and random match probability are two common approaches. After assumptions are made, comparisons can be made …

Computational Analysis Beyond The Monomer Frontier Orbitals For Photovoltaic Donor-Polymer Candidates, Mitchell E. Lahm, Megan M. Niblock, John M. Migliore, Kendra M. Mckenzie, Hans P. Lüthi, Rollin A. King

Chemistry Faculty Publications

Scharber et al. proposed an efficiency model for organic photovoltaic cells based on the orbital energies of the monomers of the donor- and acceptor- polymers [Advanced Materials 18 (2006) 789–794]. We report theoretical extensions of this approach. First, the frontier-orbital energies and electronic spectra of n-length oligomers (n = 1 − 5) of 3-butylthiophene have been determined. The results show reasonable convergence with respect to system size at the point of a trimer with alkyl end caps. The HOMO-LUMO gap well matches computed excitation energies. Second, the structures and electronic spectra of dimers formed by three different monomers, with various …

The 3d Printing Of Dielectric Elastomer Films Assisted By Electrostatic Force, Yuhao Wang, Yanfen Zhou, Wenyue Li, Zhanxu Liu, Bangzi Zhou, Shipeng Wen, Liang Jiang, Shaojuan Che, Jianwei Ma, Tony Betts, Stephen Jerrams, Fenglei Zhou

Articles

ompared with traditional methods for preparing dielectric elastomer (DE) films, electrohydrodynamic (EHD) 3D printing displays many advantages, notably full automation, computer control and flexible design. It also confers high printing resolution, high preparation efficiency with minimal probability of nozzle clogging. In this article, EHD 3D printing was employed to fabricate silicone rubber (SR) based DE films. In order to increase their dielectric constant, high dielectric copper phthalocyanine (CuPc) particles were added into the SR ink. Optimal printing conditions were determined by analyzing the effects of printing voltage and ink properties on the formation of liquid cone and the printed line …

Stockton

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Relevant Publications

2021 Data Summary

Reversible Electrowetting Transitions On Superhydrophobic Surfaces, D. Vanzo, A. Luzar, D. Bratko

Chemistry Publications

Electric field applied across the interface has been shown to enable transitions from Cassie to Wenzel state on superhydrophobic surfaces with miniature corrugations. Molecular Dynamics (MD) simulations manifest the possibility of reversible cycling between the two states when narrow surface wells support spontaneous expulsion of water in the absence of the field. With approximately 1 nm sized wells between the surface asperities, response times to changes of electric field are of O(0.1) ns, allowing up to GHz frequency of the cycle. Because of orientation preferences of interfacial water in contact with the solid, the phenomenon depends on the polarity of …

Photoassisted Synthesis Of Complex Polyheterocycles Via Rational Design Of Tailored Photoprecursors, Tina Alanna Holt

Electronic Theses and Dissertations

Natural products remain the most common source for drug leads, although diversity-oriented synthesis of unnatural complex molecules is gaining momentum. Our lab has been developing experimentally simple and straightforward approaches to complex molecular architectures via photochemical reactions involving a minimal number of experimental steps. In order to achieve this, photoprecursors were assembled via high yielding reactions. Next, we deployed photoinduced cycloadditions to create complex 3-dimentional structures. Lastly, with this obtained primary photoproduct, post-photochemical transformations were used to further grow its scaffold complexity.

One method to increase scaffold complexity is the [4+2] intramolecular cycloadditions of azaxylylenes, which are developed through standard …

Epr Relaxation Of Modified Triphenylmethyl And Nitroxide Radicals, Whylder Moore

Electronic Theses and Dissertations

Trityl and nitroxide radicals are widely used as probes in chemical and biochemical systems. Understanding of factors that impact the electron spin relaxation for these radicals is important for selection of probes and experimental operating conditions. It has been previously reported that ¹³C isotope enrichment of the central carbon of the trityl yields a highly sensitive micro viscosity probe. It was important to characterize the impact of this substitution on the relaxation processes in fluid solution and immobilized samples.

Electron spin relaxation times for perdeuterated Finland trityl 99% enriched in ¹³C at the central carbon (¹³C …

Validation Of A Deployable Proteomic Assay For The Serological Screening Of Sexual Assault Samples, Catherine O'Sullivan Brown

Electronic Theses and Dissertations

Protein mass spectrometry (MS) has emerged as a technique to supplant traditional serological tests for body fluid identification. It was hypothesized that proteomic techniques would surpass the sensitivity and specificity of traditional serological techniques. An automated workflow coupled with protein MS has been developed for the confirmatory identification of five biological fluids. A developmental validation was completed, assessing parameters such as reproducibility, sensitivity, ion suppression, and limit of detection. Implementation was determined through tandem sample processing by MS, traditional serological tests, and standard DNA profiling methods. The MS approach offered superior detection limits while also providing true confirmatory results, producing …

Polyesters With Main And Side Chain Phosphoesters As Structural Motives For Biocompatible Electrospun Fibres, André E. Polloni, Viviane Chiaradia, Ronaldo José F.C. Do Amaral, Cathal Kearney, Brian Gorey, Débora De Oliveira, José V. De Oliveira, Pedro H.H. De Araújo, Claudia Sayer, Andreas Heise

Articles

Phosphoester containing polymers are promising materials in biomedical applications due to their biocompatibility and biodegradability. Utilising thiol-ene chemistry, the synthesis of two novel structural polymer motives combining polyesters and phophoester groups was explored. The first polymer was obtained by coupling ene-functional poly(thioether-phosphoester) with thiol functional poly(pentadecalactone). While the coupling reaction was successful, yields remained low presumably due to inadequate endgroup stoichiometry. The second polymer comprised phosphoester side groups conjugated to unsaturated poly(globalide). Double bond conversions up to 84% were achieved depending of the type of phosphoester thiol and relative reactant ratios. The resulting polymers transitioned from solid semicrystaline to liquid …

1,4,5,8-Naphthalene Tetracarboxylate Dianhydride/G-C3N4 Van Der Waals Heterojunctions Exhibit Enhanced Photochemical H2O2 Production And Antimicrobial Activity, John H. Thurston, Molly Vitale-Sullivan, Azhar Koshkimbayeva, Tyler R. Smith, Kenneth A. Cornell

Chemistry and Biochemistry Faculty Publications and Presentations

Organic semiconductors, including graphitic carbon nitride (g-C₃N₄, CN), represent an important class of materials for the development of novel antimicrobial or biomedical technologies. Of principal interest is the ability of these materials to catalyze the reduction of elemental oxygen to generate reactive oxygen species (ROS), including hydrogen peroxide (H₂O₂). Here, we describe the fabrication of photoactive van der Waals heterojunctions incorporating 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTCDA) and CN. The composite heterojunction systems were characterized by a combination of physical (TEM, SEM, pXRD), spectroscopic (FT-IR, XPS, DRUV, photoluminescence, TCSPC) and kinetic experiments. Electronic interactions …

Big Data Analysis Of Nanoscience Bibliometrics, Patent, And Funding Data (2000-2019), Yuliang Zhao, Zhixiang Wei, Qing Dai, Hongwei Dong, Hongjun Xiao, Shuxian Wu, Xingxing He, Beverley Mitchell, Thomas A. Collins, Sarah Huggett, John Van Orden, Christiane Barranguet, Basak Candemir

Public Reports

Given the strategic significance of Nanoscience and nanotechnology, it is essential to evaluate and predict its developmental trends. This report is based on the largest abstract and citation database of peer-reviewed literature, Elsevier's Scopus, along with the research evaluation platform SciVal. The funding and patent analysis data for the report is from Funding Institutional and PatentSight, respectively. This report provides an evaluation of Nanoscience's scientific output, role, contribution, and impact through bibliometric analysis, combined with big data indicators of Nanoscience scientific results and patents from 2000 to 2019.

Conversation Among Physical Chemists: Strategies And Resources For Remote Teaching And Learning Catalyzed By A Global Pandemic, Andrea N. Giordano, David Gardner, William W. Kennedy, Chrystal D. Bruce

2021 Faculty Bibliography

In the midst of a global pandemic in spring 2020, physical chemistry faculty gathered to share strategies and resources for teaching remotely. During this conversation, instructors created a shared document compiling the challenges they faced in spring 2020 and ways to improve teaching and learning in the physical chemistry classroom and laboratory when institutions reopened in the fall. We present a content analysis of the shared document that provides a snapshot of physical chemists’ thoughts at that moment in June 2020. The themes that emerged from our analysis are assessment, choice of learning objectives, course management, opportunities, resources, student motivation, …

Synthesis And Reactivity Of Metal Bis(Alkoxide) Complexes In Nitrene Coupling And Polymerization Of Polar Monomers, Duleeka Chamini Wannipurage

Wayne State University Dissertations

The nitrene homocoupling to produce azoarenes was done using two different iron (II) alkoxide complexes, Fe(OCtBu2(3,5-Ph2C6H3)2(THF)2 and Fe[OO]Ph(THF)2. Due to the steric bulkiness of HOCtBu2(3,5-Ph2C6H3 ligand, this complex exhibited selectivity for the bis(alkoxide) ligation; no tris(alkoxide) complexes were observed. As a result, both bulky and non-bulky aryl nitrenes are coupled with Fe(OCtBu2(3,5-Ph2Ph)2(THF)2, albeit the coupling of the less bulky substrates requires higher temperatures and longer reaction times. Stoichiometric reactions of Fe(OCtBu2(3,5-Ph2C6H3)2(THF)2 with non-bulky aryl azides led to the observation of the iron(III) tetrazene radical anion complexes, that can produce azoarene products after heating. Tetrazene complexes likely serve as a “masked …

Synthetic Pathways For Potential Platinum 1,10-Phenanthroline Compounds, Jacob Young

Mahurin Honors College Capstone Experience/Thesis Projects

There are extremely important uses for platinum when it comes to the treatment of cancers and dementias. One potential therapeutic combines platinum with a structure known as phenanthroline. This platinum phenanthroline structure is normally extremely water-insoluble, rendering it difficult to study and use in biological systems. The Williams’ Biochemistry Laboratory endeavored to find a simpler synthetic pathway for a water-soluble phenanthroline product. While unsuccessful in identifying a product as of yet, many synthetic pathways have been ruled out, and more hypothetical pathways are being formulated for testing.

Among the strategies analyzed are varying solvent, reagents, apparatus, methodology, and temperature in …

Degradation Of Natural And Synthetic Fibers In Various Aqueous Environments, Jaylin Bryant

Honors Scholars Collaborative Projects

Fabrics are one variant of polymers, macromolecules that form the foundation of our society. They consist of small subunits called monomers, which are covalently bonded together and layered over each other through intermolecular attractions. There are natural fabrics, such as cotton and silk, and synthetic fabrics like polyester and rayon. Scientists in forensic taphonomy study postmortem changes made to human remains, which can also include clothes found at the scene. In this study, the degradation rates of four white fabrics (cotton, polyester, rayon, and silk) were observed in various aqueous environments (pure, chlorinated, sea, and lake) in order to observe …

The Formation Of Prenucleation Clusters For Calcium Fluoride, Taylor M. Muterspaw

Browse all Theses and Dissertations

There have been limited studies on the analysis of the nucleation and precipitation behind calcium fluoride. Earlier studies support a nucleation mechanism in agreement to classical nucleation theory (CNT) in which a surface nucleation mechanism is required for calcium fluoride. This experiment devised using the ISE method to calcium fluoride to find evidence of a nucleation mechanism like that of calcium carbonate (prenucleation cluster pathway). The potential and pH were recorded versus time and the potential data was converted to nCa2+ data of free calcium ions. It was determined that there was evidence of a similar nucleation mechanism for calcium …

Analyzing Single Ion Channel Activity In A Lipid Bilayer, David Ruiter, Loren Haarsma

Summer Research

Bilayers of lipid molecules form the basis of the cell membranes in living organisms. An ion channel is a type of molecule that can temporarily open a channel in a lipid bilayer in order to allow specific ions in and out. Problems with ion channels and their interactions with lipid bilayers are associated with several diseases, including osteoporosis. Carefully controlling the type of lipid in the bilayer, and its temperature, gives us tools to study the basic biophysics of these systems

Effects Of Resin Chemistries On The Selective Removal Of Industrially Relevant Metal Ions Using Wafer-Enhanced Electrodeionization, Humeyra B. Ulusoy Erol, Christa N. Hestekin, Jamie A. Hestekin

Chemical Engineering Faculty Publications and Presentations

Wafer-enhanced electrodeionization (WE-EDI) is an electrically driven separations technology that occurs under the influence of an applied electric field and heavily depends on ion exchange resin chemistry. Unlike filtration processes, WE-EDI can be used to selectively remove ions even from high concentration systems. Because every excess ion transported increases the operating costs, the selective separation offered by WE-EDI can provide a more energy-efficient and cost-effective process, especially for highly concentrated salt solutions. This work reports the performance comparison of four commonly used cation exchange resins (Amberlite IR120 Na⁺, Amberlite IRP 69, Dowex MAC 3 H⁺, and …

Ferrocenium Complex Aided O-Glycosylation Of Glycosyl Halides, Deva Saroja Talasila, Eike B. Bauer

Educator Preparation & Leadership Faculty Works

A new strategy for the activation of glycosyl halide donors to be utilized in glycosylation reactions is presented, utilizing the ferrocenium (Fc) complexes [FcB(OH)2]SbF6 and FcBF4 as promoters. The scope of the new system has been investigated using glycosyl chloride and glycosyl fluoride donors in combination with common glycosyl acceptors, such as protected glucose. The corresponding glycosylation products were formed in 95 to 10% isolated yields with α/β ratios ranging from 1/1 to β only (2 to 14 h reaction time at room temperature, 40 to 100% ferrocenium promoter load).

Soil Research Project, Kate Donaldson

Natural Sciences Student Research Presentations

My topic is how earthworms interact with soil. Most people learn from an early age that earthworms are an important part of soil and plant life, but many do not know the actual reasoning and evidence behind it. My audience would be interested in this topic because it is interesting to expand knowledge on things already considered well know. While many earthworms are not endangered, we still need to be carful and protect the animal that is vital to plant growth and soil health.