Investigating The Impact Of Secondary Activation Time On The Adsorption Properties Of Activated Biochar For Arsenic Removal From Wastewater,
2024
University of South Alabama
Investigating The Impact Of Secondary Activation Time On The Adsorption Properties Of Activated Biochar For Arsenic Removal From Wastewater, Achyuth Bharadwaj Rayarao
Graduate Theses and Dissertations (2019 - present)
Biochar, a naturally occurring and renewable carbon material, becomes porous through activation. Activated biochar is an ideal candidate for use as an adsorbent. The objective of this study is to investigate whether activated biochar derived from Colorado soft pine serves as a better adsorbent and demonstrates enhanced adsorption capabilities after undergoing secondary physical activation at various activation times. The effect of secondary action time on physical adsorption properties drawn from the analysis of isotherm plots, surface areas and pore size patterns were examined by using a physisorption analyzer. Chemical structures were identified using both ultimate and proximate analyses, while porosity …
Enabling More Efficient Solar Thermal Energy Production And Storage,
2024
University of South Alabama
Enabling More Efficient Solar Thermal Energy Production And Storage, Allan Wilson
Poster Presentations
Concentrated Solar Power (CSP) stores & transfers energy using a Thermal Energy Storage Fluid (EIA AEO 2022)
Development Of An Enhanced Sampling Workflow To Accelerate Molecular Docking With Sparse Biophysical Information,
2024
Western Kentucky University
Development Of An Enhanced Sampling Workflow To Accelerate Molecular Docking With Sparse Biophysical Information, Zachary Stichter
Masters Theses & Specialist Projects
Rapid docking of flexible biological macromolecules remains a significant open challenge in protein structure determination. While rigid docking is relatively simple with toolkits such as TagDock, a key obstacle to rapid flexible docking is the complexity and roughness of the free energy surface associated with protein conformational motion (often termed the many-minima problem), meaning conventional molecular dynamics methods do not effectively sample protein conformations near the interaction complex in accessible timescales. Methods such as metadynamics and replica exchange molecular dynamics exist to ameliorate this obstacle, yet these methods use nonphysical biases or random swaps to enhance sampling. In contrast, high …
The Purification And Thermal Stability Of The Peroxidase Enzyme In Cucurbita Moschata,
2024
Liberty University
The Purification And Thermal Stability Of The Peroxidase Enzyme In Cucurbita Moschata, Garen Hamner
Senior Honors Theses
Peroxidases are enzymes that catalyze the reduction of hydrogen peroxide to water while oxidizing organic substrates and are valuable in spheres like industrial and medical applications and histochemistry. Limitations still exist in the use of the well-studied horseradish peroxidase for certain activities due to limitations like poor thermal stability, thus the search for novel peroxidases that can overcome these limitations is an active area of research. Butternut squash peroxidase (Cucurbita moschata) (BSP) shows promise due to significant activity being found in the skin and apparent enhanced thermal stability, but an efficient purification scheme for it is lacking, as well as …
A Single Hydrogen Bond That Tunes Flavin Redox Reactivity And Activates It For Modification,
2024
University of Kentucky
A Single Hydrogen Bond That Tunes Flavin Redox Reactivity And Activates It For Modification, Debarati Das, Anne-Frances Miller
Markey Cancer Center Faculty Publications
Electron bifurcation produces high-energy products based on less energetic reagents. This feat enables biological systems to exploit abundant mediocre fuel to drive vital but demanding reactions, including nitrogen fixation and CO2 capture. Thus, there is great interest in understanding principles that can be portable to man-made devices. Bifurcating electron transfer flavoproteins (Bf ETFs) employ two flavins with contrasting reactivities to acquire pairs of electrons from a modest reductant, NADH. The bifurcating flavin then dispatches the electrons individually to a high and a low reduction midpoint potential (E°) acceptor, the latter of which captures most of the energy. Maximum efficiency …
Self-Assembly Of Core-Substituted Naphthalene Diimide Based Palladium (Ii) And Platinum (Ii) Macrocycles,
2024
St. Mary's University
Self-Assembly Of Core-Substituted Naphthalene Diimide Based Palladium (Ii) And Platinum (Ii) Macrocycles, Samantha Aragon, Camille Kwan, Franchesca Tinacba
Posters - 2024
Coordination-driven self-assembly is an efficient way to create 2D and 3D supramolecular coordination complexes (SCC) due to its predictable features of metal coordination. SCC’s represent a growing area of research with applications in various fields such as host-guest chemistry, catalysis, chemical transfer and separation, and stabilization of its reactive intermediate. Integrating various fluorophore/chromophore into these SCC’s results in unique properties and functions. In this project, core-substituted naphthalenediimide (NDI) based macrocycles were constructed via self-assembly with 90° platinum (II) and palladium (II) phosphane triflates.1H NMR and 31P NMR studies of the self-assembled product in various nonpolar to polar solvents showed two …
Myeloid-Derived Suppressor Cell Mitochondrial Fitness Governs Chemotherapeutic Efficacy In Hematologic Malignancies,
2024
Roswell Park Comprehensive Cancer Center
Myeloid-Derived Suppressor Cell Mitochondrial Fitness Governs Chemotherapeutic Efficacy In Hematologic Malignancies, Saeed Daneshmandi, Jee Eun Choi, Qi Yan, Cameron R. Macdonald, Manu Pandey, Mounika Goruganthu, Nathan Roberts, Prashant K. Singh, Richard M. Higashi, Andrew N. Lane, Teresa W-M Fan, Jianmin Wang, Philip L. Mccarthy, Elizabeth A. Repasky, Hemn Mohammadpour
Markey Cancer Center Faculty Publications
Myeloid derived suppressor cells (MDSCs) are key regulators of immune responses and correlate with poor outcomes in hematologic malignancies. Here, we identify that MDSC mitochondrial fitness controls the efficacy of doxorubicin chemotherapy in a preclinical lymphoma model. Mechanistically, we show that triggering STAT3 signaling via β2-adrenergic receptor (β2-AR) activation leads to improved MDSC function through metabolic reprogram- ing, marked by sustained mitochondrial respiration and higher ATP generation which reduces AMPK signaling, altering energy metabolism. Furthermore, induced STAT3 signaling in MDSCs enhances glutamine consumption via the TCA cycle. Metabolized glutamine generates itaconate which downregulates mitochondrial reactive oxygen species via regulation of …
Leveraging The Hmbc To Facilitate Metabolite Identification,
2024
University of Nebraska - Lincoln, University of Pittsburgh School of Medicine
Leveraging The Hmbc To Facilitate Metabolite Identification, Fatema Bhinderwala, Thao Vu, Thomas G. Smith, Julian Kosacki, Darrell D. Marshall, Yuhang Xu, Martha D. Morton, Robert Powers
Department of Chemistry: Faculty Publications
The accuracy and ease of metabolite assignments from a complex mixture are expected to be facilitated by employing a multi-spectral approach. The 2D 1H-13C HSQC and 2D 1H-1H-TOCSY are the experiments commonly used for metabolite assignments. The 2D 1H-13C HSQC-TOCSY and 2D 1H-13C HMBC are routinely used by natural products chemists but have seen minimal usage in metabolomics despite the unique information, the nearly complete 1H-1H and 1H-13C and spin systems provided by these experiments that may improve the accuracy and reliability …
Β-Sheets Mediate The Conformational Change And Allosteric Signal Transmission Between The Aslov2 Termini,
2024
Southern Methodist University
Β-Sheets Mediate The Conformational Change And Allosteric Signal Transmission Between The Aslov2 Termini, Sian Xiao, Mayar Terek Ibrahim, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao
Mathematics, Physics, and Computer Science Faculty Articles and Research
Avena sativa phototropin 1 light-oxygen-voltage 2 domain (AsLOV2) is a model protein of Per-Arnt-Sim (PAS) superfamily, characterized by conformational changes in response to external environmental stimuli. This conformational change begins with the unfolding of the N-terminal A'α helix in the dark state followed by the unfolding of the C-terminal Jα helix. The light state is characterized by the unfolded termini and the subsequent modifications in hydrogen bond patterns. In this photoreceptor, β-sheets are identified as crucial components for mediating allosteric signal transmission between the two termini. Through combined experimental and computational investigations, the Hβ …
Tunable Magnetic Coupling In Graphene Nanoribbon
Quantum Dots,
2024
University of California, Berkeley
Tunable Magnetic Coupling In Graphene Nanoribbon Quantum Dots, Peter H. Jacobse, Mamun Sarker, Anshul Saxena, Brookhaven National Laboratory, Ziyi Wang, Emma Berger, Narayana R. Aluru, Alexander Sinitskii, Michael F. Crommie
Department of Chemistry: Faculty Publications
Carbon-based quantum dots (QDs) enable flexible manipulation of electronic behavior at the nanoscale, but controlling their magnetic properties requires atomically precise structural control. While magnetism is observed in organic molecules and graphene nanoribbons (GNRs), GNR precursors enabling bottom-up fabrication of QDs with various spin ground states have not yet been reported. Here the development of a new GNR precursor that results in magnetic QD structures embedded in semiconducting GNRs is reported. Inserting one such molecule into the GNR backbone and graphitizing it results in a QD region hosting one unpaired electron. QDs composed of two precursor molecules exhibit nonmagnetic, antiferromagnetic, …
De Novo Drug Design Using Transformer-Based Machine Translation And Reinforcement Learning Of An Adaptive Monte Carlo Tree Search,
2024
Chapman University
De Novo Drug Design Using Transformer-Based Machine Translation And Reinforcement Learning Of An Adaptive Monte Carlo Tree Search, Dony Ang, Cyril Rakovski, Hagop S. Atamian
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
The discovery of novel therapeutic compounds through de novo drug design represents a critical challenge in the field of pharmaceutical research. Traditional drug discovery approaches are often resource intensive and time consuming, leading researchers to explore innovative methods that harness the power of deep learning and reinforcement learning techniques. Here, we introduce a novel drug design approach called drugAI that leverages the Encoder–Decoder Transformer architecture in tandem with Reinforcement Learning via a Monte Carlo Tree Search (RL-MCTS) to expedite the process of drug discovery while ensuring the production of valid small molecules with drug-like characteristics and strong binding affinities towards …
Synthesis And Characterization Of Bio Based Amphiphilic Molecules,
2024
SASTRA Deemed to be University
Synthesis And Characterization Of Bio Based Amphiphilic Molecules, Vandana Singh
Theses and Dissertations
Among various molecular self-assemblies, low molecular weight gelators (LMWGs), that can form gels in organic solvents/water/oils, have gained much research attention due to their huge potential applications. Generally, gels are soft nanomaterials formed by the self-assembly of amphiphilic molecules into a three-dimensional fibrous network entrapping the solvent.
As these gels are formed by self-assembly via non-covalent interactions they are reversible and differ from macromolecular gels. To synthesize LMWGs, biomolecules such as fats, oils, fatty acids, lignocelluloses, sugars, amino acids, and peptides are commonly used as their inherent property favors self-assembly. In the current scenario, interest in synthesizing bio-based gelators has …
Group 14 Metallocene Catalysts For Carbonyl Hydroboration And Cyanosilylation,
2024
Chapman University
Group 14 Metallocene Catalysts For Carbonyl Hydroboration And Cyanosilylation, Haley J. Robertson, Mallory N. Fujiwara, Allegra L. Liberman-Martin
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
A series of six Group 14 metallocene compounds (M = Ge, Sn, Pb) were studied as catalysts for carbonyl hydroboration and cyanosilylation reactions at room temperature. Both bis(pentamethylcyclopentadienyl) and tetramethyldisiloxa[3]metallocenophane compounds were compared. The tin and lead metallocenophanes exhibited the highest reactivity in hydroboration and cyanosilylation reactions. Hammett analysis of aldehyde hydroboration provided a ρ value of 0.73, suggesting a buildup of negative charge during the turnover-limiting step, consistent with the transition state for hydride transfer to the carbonyl center. NMR studies of Lewis acidity indicate that the Ge, Sn, and Pb tetramethyldisiloxa[3]metallocenophane compounds are weak Lewis acids.
Temperature-Dependent Stress–Strain Behavior Of Amorphous And Crystalline P3ht,
2024
University of Kentucky
Temperature-Dependent Stress–Strain Behavior Of Amorphous And Crystalline P3ht, Kehinde H. Fagbohungbe, Connor P. Callaway, Chad Risko
UK CARES Faculty Publications
The scalable commercialization of organic electronics wherein p-conjugated polymers serve as the semiconductors hinges on precise control of the material electronic, redox, optical, and mechanical properties, which are each highly influenced by local and long-range morphology. Here, we undertake atomistic molecular dynamics (MD) simulations at three temperatures (150 K, 300 K, and 400 K) to assess the morphological and mechanical response of bulk poly(3-hexylthiophene) (P3HT), a representative homopolymer of interest as an organic semiconductor (OS). As P3HT is a semicrystalline polymer, we characterize mechanical properties for both amorphous and crystalline P3HT models to derive insights into structure–property relationships, including Young’s …
Problems In Chemical Graph Theory Related To The Merrifield-Simmons And Hosoya Topological Indices,
2024
Georgia Southern University
Problems In Chemical Graph Theory Related To The Merrifield-Simmons And Hosoya Topological Indices, William B. O'Reilly
College of Graduate Studies: Theses & Dissertations
In some sense, chemical graph theory applies graph theory to various physical sciences. This interdisciplinary field has significant applications to structure property relationships, as well as mathematical modeling. In particular, we focus on two important indices widely used in chemical graph theory, the Merrifield-Simmons index and Hosoya index. The Merrifield-Simmons index and the Hosoya index are two well-known topological indices used in mathematical chemistry for characterizing specific properties of chemical compounds. Substantial research has been done on the two indices in terms of enumerative problems and extremal questions. In this thesis, we survey known extremal results and consider the generalized …
Inorganic Chemical Reasoning Skills: An Exploratory Study Into Understanding Students’ Choices And Thought Processes,
2024
Missouri State University
Inorganic Chemical Reasoning Skills: An Exploratory Study Into Understanding Students’ Choices And Thought Processes, Hannah P. Thompson
Graduate Theses/Dissertations
Predicting the products of reactions is a fundamental skill for practicing inorganic chemists. However, the current knowledge of the strategies that students use to solve them is limited. Presumably, instructors of inorganic chemistry courses give complete-the-reaction assessment items hoping that students will use their knowledge of inorganic concepts to solve them; but it is conceivable that a successful student could use heuristics or domain general problem-solving methods. I proposed this study to determine which strategies were used by students when solving complete-the-reaction tasks in inorganic chemistry, and also to make qualitative connections between strategy and accuracy. This was done in …
Α-Hydroxy C–H Functionalization Of Alcohols Via Boronic Acid, Hat, Photoredox Triad Catalytic System,
2024
West Virginia University
Α-Hydroxy C–H Functionalization Of Alcohols Via Boronic Acid, Hat, Photoredox Triad Catalytic System, Seth Christopher Cowan
Graduate Theses, Dissertations, and Problem Reports (ETD)
This dissertation explores the research that I have conducted in my time at West Virginia University. Most of my work has focused on the development of methods and studies to further understand the α-OH C–H functionalization of alcohols. This work involves a system of catalysts including photocatalysts, HAT catalysts, and boronic acid catalysts. Chapter 1 highlights a background for each of these areas. Photoredox catalysis has been an increasing area of chemistry over the past two decades as this technique can be used to design conditions to form new bonds in a selective manner through the utilization of light energy. …
Extended Conformations Of Bifurcating Electron Transfer Flavoprotein Constitute Up To Half The Population, Possibly Mediating Conformational Change,
2024
University of Kentucky
Extended Conformations Of Bifurcating Electron Transfer Flavoprotein Constitute Up To Half The Population, Possibly Mediating Conformational Change, Sharique A. Khan, Alan Hicks, Wellington C. Leite, James Byrnes, Biswajit Gorai, Maria-Andrea Mroginski, Hugh O'Neill, Anne-Francis Miller
Markey Cancer Center Faculty Publications
Electron transfer bifurcation enables biological systems to drive unfavourable (endergonic) electron transfer by coupling it to favourable (exergonic) transfer of a second electron. In electron transfer flavoproteins (ETFs), a domain-scale conformational change is believed to sever the favourable pathway after a single electron has used it, thereby preventing the energy dissipation that would accompany exergonic transfer of the second electron. To understand the conformation change that participates in turnover, we have deployed small-angle neutron scattering (SANS) and computational techniques to characterize the bifurcating ETF from Acidaminococcus fermentans (AfeETF). SANS data reveal an overall radius of gyration (Rg) of 30.1 ± …
Perfluorooctanesulfonic Acid Exposure Leads To Downregulation Of 3-Hydroxy-3-Methylglutaryl-Coa Synthase 2 Expression And Upregulation Of Markers Associated With Intestinal Carcinogenesis In Mouse Intestinal Tissues,
2024
University of Kentucky
Perfluorooctanesulfonic Acid Exposure Leads To Downregulation Of 3-Hydroxy-3-Methylglutaryl-Coa Synthase 2 Expression And Upregulation Of Markers Associated With Intestinal Carcinogenesis In Mouse Intestinal Tissues, Josiane Weber Tessmann, Pan Deng, Jerika Durham, Chang Li, Moumita Banerjee, Qingding Wang, Ryan A. Goettl, Daheng He, Chi Wang, Eun Y. Lee, B. Mark Evers, Bernhard Hennig, Yekaterina Y. Zaytseva
Markey Cancer Center Faculty Publications
Perfluorooctanesulfonic acid (PFOS) is a widely recognized environment pollutant known for its high bio- accumulation potential and a long elimination half-life. Several studies have shown that PFOS can alter multiple biological pathways and negatively affect human health. Considering the direct exposure to the gastrointestinal (GI) tract to environmental pollutants, PFOS can potentially disrupt intestinal homeostasis. However, there is limited knowledge about the effect of PFOS exposure on normal intestinal tissues, and its contribution to GI- associated diseases remains to be determined. In this study, we examined the effect of PFOS exposure on the gene expression profile of intestinal tissues of …
The Relationship Between Metacognition, Study Strategies, And Students’ Performances In General Chemistry And Organic Chemistry Courses,
2024
West Virginia University
The Relationship Between Metacognition, Study Strategies, And Students’ Performances In General Chemistry And Organic Chemistry Courses, Nghiem Uy Tieu
Graduate Theses, Dissertations, and Problem Reports (ETD)
Many students find General Chemistry challenging, and studies have shown a link between students’ grades in chemistry and a decrease in interest in STEM fields. Similarly, Organic Chemistry has also been typically identified as a difficult course for many undergraduate students and has a notoriously high failure rate. Numerous studies have explored various methods to enhance students’ performance and experience in both General Chemistry and Organic Chemistry, but there hasn’t been much focus on students’ study strategies. In addition, metacognition, the skill of thinking about one’s thinking, had been proven in studies as a vital role in enhancing students’ achievements. …
