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Diagnosing Discharge Events Within A Novel Miniature Simplified Coaxial Ion Trap Mass Analyzer, David Virgil Sirbescu-Stanley Apr 2024

Diagnosing Discharge Events Within A Novel Miniature Simplified Coaxial Ion Trap Mass Analyzer, David Virgil Sirbescu-Stanley

Masters Theses

Mass spectrometry is a technique that organizes material samples by mass to reveal their chemical composition by forming a spectrum. Since their invention, ion trap mass spectrometers have undergone significant enhancements. This work, funded by the National Science Foundation and in collaboration with Brigham Young University, the Simplified Coaxial Ion Trap (SCIT), attempts to simplify ion trap geometry and combine three ion traps into one device. Successful demonstration of the SCIT functionality could reduce costs, reduce manufacturing complexity, and shrink total instrument volume. At the same time, trapping capacity and analytical efficiency will be increased. However, as discussed within, challenges …


Investigating Ocean Carbonate System Changes Across Latitudes In The North Atlantic Basin With A Time-Series Mooring System, Anna Trujillo Apr 2024

Investigating Ocean Carbonate System Changes Across Latitudes In The North Atlantic Basin With A Time-Series Mooring System, Anna Trujillo

Independent Study Project (ISP) Collection

The world ocean, specifically the Arctic, serves as one of the greatest mitigators for anthropogenic carbon dioxide release, making the study of high latitude ocean carbonate chemistry an increasingly important topic. While much work has been done concerning the science of acidification and future model projections, analyzing data to detect decadal anthropogenic trends and effects is also highly important. Aiming to add to this data pool, this study investigated the ocean carbonate system at three North Atlantic mooring locations at polar, subtropical, and tropical latitudes from 2013 - 2021. Time series datasets of the pH and pCO₂ of surface water …


Magnetic Properties And Biological Relevance Of Scorpionate-Based Transition Metal Complexes, Laxmi Devkota Apr 2024

Magnetic Properties And Biological Relevance Of Scorpionate-Based Transition Metal Complexes, Laxmi Devkota

Dissertations (1934 -)

There are two major components to this research dissertation. The first component describes the synthesis and characterization of high-spin, first-row transition metal complexes supported by facially-coordinating “scorpionate” ligands. These studies have sought to uncover fundamental relationships between molecular structure and magnetic properties, with the ultimate aim of assisting in the design of single molecule magnets (SMMs). To this end, comprehensive series of four and five-coordinated M(II)-X complexes (M = Co, Fe, and Cu; and X = F, Cl, Br, and I) were prepared using hydrotris(pyrazol-1-yl)borate ligands (TpR,R’; where R and R’ indicate substituents at the 3- and 5-position of the …


Elucidating The Effect Of Surface Modifications On Nanomaterial Function, Nicholas Langer Apr 2024

Elucidating The Effect Of Surface Modifications On Nanomaterial Function, Nicholas Langer

Dissertations (1934 -)

Nanoparticles (NPs) are an exciting class of materials with unique properties that inspire their use in sensing, catalysis, optoelectronic devices, and more. NPs are frequently coated in organic molecules, termed ligands, to increase their stability, but ligands also influence NP catalytic activity and their interactions with neighboring molecules. To fully realize the potential of nanomaterials as key components in novel complex systems, a more nuanced understanding of the relationships between NPs, ligands, and their surrounding microenvironment is critical. After a brief review of the NP field in Chapter 1, Chapter 2 begins the investigation of structure-function relationships with a cross-class …


Multifunctional Nanomaterial Analysis Using Inexpensive Techniques, Casey Jordan , '24 Apr 2024

Multifunctional Nanomaterial Analysis Using Inexpensive Techniques, Casey Jordan , '24

Senior Theses, Projects, and Awards

Designing methods to comprehensively understand nanomaterial interactions is of paramount importance as nanomaterials gain widespread use and their environmental impact becomes a concern. While current characterization methods are suitable for initial assessments, there is a need for comprehensive techniques to evaluate end-of-use scenarios and environmental effects. This report emphasizes the potential of electrochemistry as a versatile measurement tool for nanomaterial analysis. Two projects are presented, showcasing innovative analytical architectures to overcome the limitations of existing techniques. Project 1 integrates linear sweep stripping voltammetry (LSSV) and particle impact voltammetry (PIV) to achieve kinetic resolution and size analysis of silver nanoparticles (AgNPs) …


Differences In The Metabolic Outputs Of Caulobacter Crescentus Modify The Kinetics Of Silver Nanoparticle Dissolution, Tyler M. Hicks , '24 Apr 2024

Differences In The Metabolic Outputs Of Caulobacter Crescentus Modify The Kinetics Of Silver Nanoparticle Dissolution, Tyler M. Hicks , '24

Senior Theses, Projects, and Awards

Silver nanoparticles (AgNPs) are widely used within commercial products due to their distinct antibacterial and antimicrobial properties. As their utilization continues to increase, their inevitable improper disposal could present lasting environmental ramifications due to their nonspecific biotoxicity. One microorganism of interest is Caulobacter crescentus, a common freshwater bacterium found in locations where AgNPs end after their disposal. C. crescentus has two distinct cell types—a stalked and a swarmer form—each with their own unique function and metabolic outputs. Approximately 15% of the C. crescentus metabolome varies with cell cycle, thus making this an interesting and environmentally relevant model organism for …


Thinking Outside The Membrane: Investigating The Structure Of The Influenza A M2 Ectodomain, Kyra Roepke , '24 Apr 2024

Thinking Outside The Membrane: Investigating The Structure Of The Influenza A M2 Ectodomain, Kyra Roepke , '24

Senior Theses, Projects, and Awards

Influenza A leads to annual epidemics that result in three-to-five million cases of severe illness each year and occasional devastating pandemics. Some current prevention and treatment methods target the M2 membrane protein on the surface of the virus. However, viral mutability and drug resistance require the targeting of more conserved parts of the protein.

The goal of this thesis was to investigate the secondary structure and dynamics of the M2 ectodomain (M2e), which is highly conserved across influenza viruses and across evolutionary time. The structure of M2e has previously been challenging to study because of its flexibility. In this study, …


Synthesis And Characterization Of Heavy-Metal Oxoanion- And Phosphonate-Binding Nanojars, Pooja Singh Apr 2024

Synthesis And Characterization Of Heavy-Metal Oxoanion- And Phosphonate-Binding Nanojars, Pooja Singh

Dissertations

Nanojars are an emerging class of anion-binding and extraction agents. These supramolecular coordination complexes (2 nm wide) exhibit exceptional anion binding strength that points to their possible application in the recovery of toxic or valuable anions from water bodies. Nanojars of the formula (TBA)2[XO3/42−⸦{CuII(μ-OH)(μ-pyrazolate)}n] (TBA = tetrabutylammonium cation; XO3/42− = anion; X = Se, Te, Cr, Mo, W, HP, HAs, HV; n = 26 – 36) are synthesized from Cu2+, OH−, pyrazole and the TBA salts of various anions. Nanojars possess hydrophobic exteriors with an array of pyrazolate ligands and hydrophilic interiors with a …


An Exploration Of Secondary School Science Teacher’S Epistemological Belief In Malang, Anindyta Nur Rizkyana Safitri, Endang Purwaningsih, Nuril Munfaridah, Alif Darmawan Mar 2024

An Exploration Of Secondary School Science Teacher’S Epistemological Belief In Malang, Anindyta Nur Rizkyana Safitri, Endang Purwaningsih, Nuril Munfaridah, Alif Darmawan

Jurnal Pendidikan Sains

The objective of this study is to delve into the epistemological convictions of secondary school science teachers in Malang across various tenures, namely senior teachers, junior teachers, and pre-service teachers. Employing an explanatory sequential design model, the research employs a mixed-method approach. Quantitative data, gathered through the administration of the Scientific Epistemology Beliefs Questionnaire (n = 30), are complemented by qualitative insights drawn from interviews with teachers (n = 6) concerning their epistemological orientations. Descriptive statistics and qualitative analyses, utilizing an a priori coding technique aligned with the study’s conceptual framework, were conducted on the interview data. Quantitative analysis reveals …


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 Mar 2024

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 …


Fostering Engagement And Learning Outcomes: A Comparative Analysis Of Ethnochemical And Stem-Based Pedagogies For Chemistry Learning In Vocational High Schools, Maulidya Husnul Khatimah, Lismi Animatul Chisbiyah Mar 2024

Fostering Engagement And Learning Outcomes: A Comparative Analysis Of Ethnochemical And Stem-Based Pedagogies For Chemistry Learning In Vocational High Schools, Maulidya Husnul Khatimah, Lismi Animatul Chisbiyah

Jurnal Pendidikan Sains

In contemporary education, the perceived difficulty of learning chemistry, attributed to its abstract nature, remains a challenge for many students. This difficulty is compounded by a notable lack of alignment between chemistry concepts and students’ daily experiences, despite the inherent relevance of chemistry to their everyday phenomena. Building on previous research affirming the efficacy of ethnochemical modules in enhancing student learning and achievement, this study investigates the suitability of a STEM-based approach for chemistry education, particularly in vocational high school. The research methodology employs a literature study method, utilizing the PICO(T) framework for keyword selection. A rigorous review and analysis …


Differences In Biology Students’ Self-Regulation During Online And Offline Learning And Its Relationship To Learning Outcomes, Adi Kus Rochman Jk, Dwi Listyorini, Fatchur Rohman, Yessi Affriyenni Mar 2024

Differences In Biology Students’ Self-Regulation During Online And Offline Learning And Its Relationship To Learning Outcomes, Adi Kus Rochman Jk, Dwi Listyorini, Fatchur Rohman, Yessi Affriyenni

Jurnal Pendidikan Sains

The cultivation of self-regulatory skills holds paramount importance for individuals’ future success, particularly in the context of evolving educational modalities prompted by the Covid-19 pandemic. As learning transitions between online during the pandemic and offline post-pandemic, understanding the nuances of self-regulation becomes imperative. Thus, this study sought to achieve three objectives: (1) analyzing disparities in student self-regulation between online and offline settings, (2) examining the interplay between online and offline self-regulation, and (3) scrutinizing the relationship between self-regulation and learning outcomes. Employing a methodological approach involving questionnaire administration, interviews, and collecting academic scores data, data analysis was conducted utilizing the …


Can Argument-Driven Inquiry-Assisted Virtual Laboratory Improve Pre-Service Physics Teachers’ Mastery Concept Of Simple Harmonic Oscillation?, Yolanda Dwi Vivian Karawahenni, Sutopo Sutopo, Arif Hidayat, Maya Mustika Mar 2024

Can Argument-Driven Inquiry-Assisted Virtual Laboratory Improve Pre-Service Physics Teachers’ Mastery Concept Of Simple Harmonic Oscillation?, Yolanda Dwi Vivian Karawahenni, Sutopo Sutopo, Arif Hidayat, Maya Mustika

Jurnal Pendidikan Sains

This study endeavors to ascertain the efficacy of the Argument-Driven Inquiry (ADI)- assisted virtual laboratory learning model in enhancing the comprehension of simple harmonic oscillation concepts among pre-service physics teachers. Employing a mixed- method approach with an embedded experimental design, the investigation employs a reasoned multiple-choice instrument comprising 15 questions. Analysis of the results reveals a noteworthy 48.38% increase in the average mastery of concepts between the pre-test and post-test, yielding an N-gain value of 0.63. Statistical scrutiny through paired sample t-tests corroborates significant disparities between pre-test and post-test scores, evidenced by a tcount (16.28) exceeding the critical ttable value …


Error Analysis Of Learners’ Problem-Solving Abilities In Mathematics Courses: A Newman Error Analysis (Nea) Approach, Aprilita Ekasari, Don Jaya Putra Mar 2024

Error Analysis Of Learners’ Problem-Solving Abilities In Mathematics Courses: A Newman Error Analysis (Nea) Approach, Aprilita Ekasari, Don Jaya Putra

Jurnal Pendidikan Sains

This study endeavors to systematically discern the spectrum of learner errors manifesting in problem-solving processes within the domain of mathematics, specifically focusing on the intricacies of integration, utilizing Newman Error Analysis (NEA) as the guiding framework. The cohort under investigation comprises 14 first-year students hailing from the Department of Physics Education at Musamus University, Merauke. Employing a descriptive methodology underscored by a qualitative orientation, this research incorporates tests and interviews as primary instruments for data collection. The tests are designed to meticulously evaluate the array of errors committed by learners, as per the tenets of Newman’s model. Additionally, a subset …


Synthesis, Molecular Characteristics, And Antibacterial Assessment Of Marine Hydroid Aqueous Extract-Based Silver Bio-Nanoparticles, Fredryk Mandey, Aulia Rhamdani Arfan, Rugaiyah Andi Arfah Mar 2024

Synthesis, Molecular Characteristics, And Antibacterial Assessment Of Marine Hydroid Aqueous Extract-Based Silver Bio-Nanoparticles, Fredryk Mandey, Aulia Rhamdani Arfan, Rugaiyah Andi Arfah

Makara Journal of Science

This investigation aims to synthesize, analyze the molecularity, and test the ability of bacterial inhibition capability of silver nanoparticles that have been synthesized by simply mixing silver nitrate and aqueous extracts of marine natural products with and without the addition of amylum as a stabilizing agent. This research, with and without the addition of amylum as a stabilizing agent, obtained 39.0 and 55.2 mg of solids of round-shaped morphology silver nanoparticles with diameters of 87.9 and 103.0 nm., respectively. In addition, the antibacterial testing assay against Staphylococcus aureus and Escherichia coli showed some considerably good results. S. aureus with the …


Recent Advances In Solar Photo(Electro)Catalytic Nitrogen Fixation, Jun-Bo Ma, Sheng Lin, Zhiqun Lin, Lan Sun, Chang-Jian Lin Mar 2024

Recent Advances In Solar Photo(Electro)Catalytic Nitrogen Fixation, Jun-Bo Ma, Sheng Lin, Zhiqun Lin, Lan Sun, Chang-Jian Lin

Journal of Electrochemistry

Ammonia (NH3) is an essential chemical in modern society. It is currently produced in industry by the Haber-Bosch process using H2 and N2 as reactants in the presence of iron-based catalysts at high-temperature (400–600 oC) and extremely highpressure (20–40 MPa) conditions. However, its efficiency is limited to 10% to 15%. At the same time, a large amount of energy is consumed, and CO2 emission is inevitably. The development of a sustainable, clean, and environmentally friendly energy system represents a key strategy to address energy crisis and environmental pollution, ultimately aiming to achieve carbon neutrality. …


Introductory Chemistry Student Success: Evaluating Peer-Led Team Learning And Describing Sense Of Belonging, Jessica D. Young Mar 2024

Introductory Chemistry Student Success: Evaluating Peer-Led Team Learning And Describing Sense Of Belonging, Jessica D. Young

USF Tampa Graduate Theses and Dissertations

Identifying approaches that make science and engineering education broader and more inclusive is core to discipline based education research. Both fundamental and applied research are important in advancing a STEM education that retains the necessary scientists of the U.S.’s future. Thus, the major goal of this work was to evaluate and describe efforts that promote student success within introductory STEM courses. This began with applied research by utilizing quantitative analyses like case-matching, logistic regression, independent sample t-tests, and repeated measures while evaluating the efficacy of peer-led team learning (PLTL). Later, this work delves into qualitative approaches to answer fundamental research …


Dynamic Fibrillar Assembly Of Αb-Crystallin Induced By Perturbation Of The Conserved Nt-Ixi Motif Resolved By Cryo-Em, Russell Mcfarland, Steve Reichow Mar 2024

Dynamic Fibrillar Assembly Of Αb-Crystallin Induced By Perturbation Of The Conserved Nt-Ixi Motif Resolved By Cryo-Em, Russell Mcfarland, Steve Reichow

Chemistry Faculty Publications and Presentations

αB-crystallin is an archetypical member of the small heat-shock proteins (sHSPs) vital for cellular proteostasis and mitigating protein misfolding diseases. Gaining insights into the principles defining their molecular organization and chaperone function have been hindered by intrinsic dynamic properties and limited high-resolution structural analysis. To disentangle the mechanistic underpinnings of these dynamical properties, we mutated a conserved IXI-motif located within the N-terminal (NT) domain of human αB-crystallin. This resulted in a profound structural transformation, from highly polydispersed caged-like native assemblies into a comparatively well-ordered helical fibril state amenable to high-resolution cryo-EM analysis. The reversible nature of the induced fibrils facilitated …


Explorations On Non-Covalent Interactions: From Supramolecules To Drug-Like Molecules, Zhanpeng Zhang Mar 2024

Explorations On Non-Covalent Interactions: From Supramolecules To Drug-Like Molecules, Zhanpeng Zhang

USF Tampa Graduate Theses and Dissertations

Non-covalent interactions are everywhere in our material world. From the microstructures of organisms to the functional materials used in industrial production, whenever matter exists, there are non-covalent interactions between the molecules that build up the matter.The exploration of non-covalent forces helps people understand the intrinsic principles of life processes, it can be applied to create new supramolecular materials as well. Supramolecular chemistry is a research field focusing on the properties and applications of non-covalent interactions. Various non-covalent interactions, such as hydrogen bonds, metal-ligand coordination, π-π interaction, hydrophobic interaction, etc., are objects of research in supramolecular chemistry.

Not only supramolecular chemists, …


Methionyl-Trna Synthetase Synthetic And Proofreading Activities Are Determinants Of Antibiotic Persistence, Whitney N. Wood, Miguel Angel Rubio, Lorenzo Eugenio Leiva, Gregory J. Phillips, Michael Ibba Mar 2024

Methionyl-Trna Synthetase Synthetic And Proofreading Activities Are Determinants Of Antibiotic Persistence, Whitney N. Wood, Miguel Angel Rubio, Lorenzo Eugenio Leiva, Gregory J. Phillips, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bacterial antibiotic persistence is a phenomenon where bacteria are exposed to an antibiotic and the majority of the population dies while a small subset enters a low metabolic, persistent, state and are able to survive. Once the antibiotic is removed the persistent population can resuscitate and continue growing. Several different molecular mechanisms and pathways have been implicated in this phenomenon. A common mechanism that may underly bacterial antibiotic persistence is perturbations in protein synthesis. To investigate this mechanism, we characterized four distinct metG mutants for their ability to increase antibiotic persistence. Two metG mutants encode changes near the catalytic site …


Synergistic Effect Of Acylpyrazolone Integrated With Multiwalled Carbon Nanotubes On The Electrochemical Analysis Of Ascorbic Acid, Emi Norzehan Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, Norhayati Hashim, Anwar Ul-Hamid, Mohamad Idris Saidin, Suyanta Suyanta, Sofian Ibrahim Mar 2024

Synergistic Effect Of Acylpyrazolone Integrated With Multiwalled Carbon Nanotubes On The Electrochemical Analysis Of Ascorbic Acid, Emi Norzehan Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, Norhayati Hashim, Anwar Ul-Hamid, Mohamad Idris Saidin, Suyanta Suyanta, Sofian Ibrahim

Makara Journal of Science

Square wave voltammetry, cyclic voltammetry, chronocoulometry, and electrochemical impedance spectroscopy were employed to assess ascorbic acid’s electrochemical behavior in multiwalled carbon nanotubes (MWCNTs)/carbon paste electrode (CPE) modified by 1-phenyl-3-methyl-4-metafluorobenzoyl-5-pyrazolone (HPMmFBP). The ascorbic acid’s irreversible oxidation peak appeared at approximately 0.5 V. The shifting of the peak potential at the pH range of 6.0–8.4 showed the involvement of protons in the ascorbic acid oxidation. Moreover, the shifting of the peak potential with scan rate in the range of 0.07–0.4 V/s confirmed that the oxidation reaction was irreversible. Under optimized conditions, the oxidative peak current showed linear dependence on the ascorbic acid’s …


In Silico Analysis Of C-Type Lectins As Co-Infection Receptors Of Dengue And Chikungunya Viruses In Aedes Aegypti, Munawir Sazali, R. C. Hidayat Soesilohadi, Nastiti Wijayanti, Tri Wibawa, Arif Nur Muhammad Ansori Mar 2024

In Silico Analysis Of C-Type Lectins As Co-Infection Receptors Of Dengue And Chikungunya Viruses In Aedes Aegypti, Munawir Sazali, R. C. Hidayat Soesilohadi, Nastiti Wijayanti, Tri Wibawa, Arif Nur Muhammad Ansori

Makara Journal of Science

Aedes aegypti is a primer vector of dengue virus (DENV) and chikungunya virus (CHIKV). The susceptibility of mosquitoes to DENV and CHIKV depends on their recognition receptor of pathogens. C-type lectins (CTLs) are an important mediator of virus infection in A. aegypti. This study aims to identify potential receptors and determine the binding affinity between ligand–receptor interaction, CTLs and virus envelopes (DENV-1, 2, 3, and 4 and CHIKV) interaction based on in silico analysis. Sample sequences were obtained from GenBank (NCBI), and 10 CTLs were acquired from VectorBase. Homology modeling based on a minimum standard of 20% was processed …


Nitrene-Transfer Chemistry To C-H And C═C Bonds Mediated By Triangular Coinage Metal Platforms Supported By Triply Bridging Pnictogen Elements Sb(Iii) And Bi(Iii), Meenakshi Sharma, Reece M. Fritz, Joseph O. Adebanjo, Zhou Lu, Thomas R. Cundari, Mohammad A. Omary, Amitava Choudhury, Pericles Stavropoulos Mar 2024

Nitrene-Transfer Chemistry To C-H And C═C Bonds Mediated By Triangular Coinage Metal Platforms Supported By Triply Bridging Pnictogen Elements Sb(Iii) And Bi(Iii), Meenakshi Sharma, Reece M. Fritz, Joseph O. Adebanjo, Zhou Lu, Thomas R. Cundari, Mohammad A. Omary, Amitava Choudhury, Pericles Stavropoulos

Chemistry Faculty Research & Creative Works

Tripodal Ligands (TMG3trphen-E) That Feature Heavy Pnictogen Elements (E = Sb(III), Bi(III)) And Tetramethylguanidinyl (TMG) Arms Have Been Explored In Stabilizing Cu(I) And Ag(I) Sites And Facilitating Nitrene-Transfer Chemistry. Compounds [(TMG3trphen-E)M3(Μ-X)3] (M = Cu(I), Ag(I); X = Cl, Br, I) Have Been Generated Upon Extraction Of M3(Μ-X)3 Units From MX Sources, Exhibiting Support Of The Crown-Shaped M3(Μ-X)3 Fragment By M-NTMG Bonds And Triply Bridging E → M3 Interactions. Orbital Interactions Between Cu(I) Sites And NTMG Residues Are More Dominant Than Sb/Bi → Cu3 Donor Interactions Between The Sb 5s Or Bi 6s Orbitals And Admixed Cu 4s/3d Orbitals, With Larger …


Efficient Removal Of Chemical Organic Demand And Total Organic Carbon From Leachate Using Heterogeneous Fenton Catalyst Based On Activated Carbon, Amar Idir, Mounir Ziati, Mohamed Bouzid Mar 2024

Efficient Removal Of Chemical Organic Demand And Total Organic Carbon From Leachate Using Heterogeneous Fenton Catalyst Based On Activated Carbon, Amar Idir, Mounir Ziati, Mohamed Bouzid

Emirates Journal for Engineering Research

Organic components contained in leachates resulting from decomposition of waste are difficult to degrade. Leachate volume and its composition vary depending on biogeochemistry of site type of deposited residues, and the age of sanitary landfill. The present study aims to develop efficient heterogeneous Fenton oxidation of organic matter, expressed in terms of chemical organic demand (COD) and total organic carbon (TOC) of leachate using the newly synthesized iron-modified activated carbon. The characterization of catalyst revealed that the Fe(II) was successfully introduced onto the original activated carbon (AC) and diversified the material’s surface morphology and elemental compounds. The heterogeneous Fenton oxidation …


Mechanistic Investigation Of C—C Bond Activation Of Phosphaalkynes With Pt(0) Complexes, Roberto M. Escobar, Abdurrahman C. Ateşin, Christian Müller, William D. Jones, Tülay Ateşin Mar 2024

Mechanistic Investigation Of C—C Bond Activation Of Phosphaalkynes With Pt(0) Complexes, Roberto M. Escobar, Abdurrahman C. Ateşin, Christian Müller, William D. Jones, Tülay Ateşin

Research Symposium

Carbon–carbon (C–C) bond activation has gained increased attention as a direct method for the synthesis of pharmaceuticals. Due to the thermodynamic stability and kinetic inaccessibility of the C–C bonds, however, activation of C–C bonds by homogeneous transition-metal catalysts under mild homogeneous conditions is still a challenge. Most of the systems in which the activation occurs either have aromatization or relief of ring strain as the primary driving force. The activation of unstrained C–C bonds of phosphaalkynes does not have this advantage. This study employs Density Functional Theory (DFT) calculations to elucidate Pt(0)-mediated C–CP bond activation mechanisms in phosphaalkynes. Investigating the …


Potential Metabolite Biomarkers Of Multiple Sclerosis From Multiple Biofluids, Fatema Bhinderwala, Heidi E. Roth, Mary Filipi, Samantha Jack, Robert Powers Mar 2024

Potential Metabolite Biomarkers Of Multiple Sclerosis From Multiple Biofluids, Fatema Bhinderwala, Heidi E. Roth, Mary Filipi, Samantha Jack, Robert Powers

Robert Powers Publications

Multiple sclerosis (MS) is a chronic and progressive neurological disorder without a cure, but early intervention can slow disease progression and improve the quality of life for MS patients. Obtaining an accurate diagnosis for MS is an arduous and error-prone task that requires a combination of a detailed medical history, a comprehensive neurological exam, clinical tests such as magnetic resonance imaging, and the exclusion of other possible diseases. A simple and definitive biofluid test for MS does not exist but is highly desirable. To address this need, we have employed NMR-based metabolomics to identify potentially unique metabolite biomarkers of MS …


The Infrared Absorption Spectrum Of Phenylacetylene And Its Deuterated Isotopologue In The Mid- To Far-Ir, Vincent J. Esposito, Pierro Ferrari, Wybren Jan Buma, Ryan C. Fortenberry, Christiaan Boersma, Alessandra Candian, Alexander G. G. M. Tielens Mar 2024

The Infrared Absorption Spectrum Of Phenylacetylene And Its Deuterated Isotopologue In The Mid- To Far-Ir, Vincent J. Esposito, Pierro Ferrari, Wybren Jan Buma, Ryan C. Fortenberry, Christiaan Boersma, Alessandra Candian, Alexander G. G. M. Tielens

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Anharmonicity strongly influences the absorption and emission spectra of polycyclic aromatic hydrocarbon (PAH) molecules. Here, IR–UV ion-dip spectroscopy experiments together with detailed anharmonic computations reveal the presence of fundamental, overtone, as well as 2- and 3-quanta combination band transitions in the far- and mid-infrared absorption spectra of phenylacetylene and its singly deuterated isotopologue. Strong absorption features in the 400–900 cm−1 range originate from CH(D) in-plane and out-of-plane wags and bends, as well as bending motions including the C≡C and CH bonds of the acetylene substituent and the aromatic ring. For phenylacetylene, every absorption feature is assigned either directly or …


A Multi-Omics Investigation Into The Mechanism Of Action Of An Anti-Tubercular Fatty Acid Analog, Isin T. Sakallioglu, Amith S. Maroli, Aline De Lima Leite, Darrell D. Marshall, Boone W. Evans, Denise K. Zinniel, Patrick H. Dussault, Raul G. Barletta, Robert Powers Mar 2024

A Multi-Omics Investigation Into The Mechanism Of Action Of An Anti-Tubercular Fatty Acid Analog, Isin T. Sakallioglu, Amith S. Maroli, Aline De Lima Leite, Darrell D. Marshall, Boone W. Evans, Denise K. Zinniel, Patrick H. Dussault, Raul G. Barletta, Robert Powers

Patrick Dussault Publications

The mechanism of action (MoA) of a clickable fatty acid analogue 8-(2-Cyclobuten-1-yl)octanoic acid (DA-CB) has been investigated for the first time. Proteomics, metabolomics, and lipidomics were combined with a network analysis to investigate the MoA of DA-CB against Mycobacterium smegmatis (Msm). The metabolomics results showed that DA-CB has a general MoA related to that of ethionamide, a mycolic acid inhibitor that targets enoyl-ACP reductase (InhA), but DA-CB likely inhibits a step downstream from InhA. Our combined multi-omics approach showed that DA-CB appears to disrupt the pathway leading to the biosynthesis of mycolic acids, an essential mycobacterial fatty acid …


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 Mar 2024

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 …


The Polyglutamine Domain Is The Primary Driver Of Seeding In Huntingtin Aggregation, Adam Skeens, Chathuranga Siriwardhana, Sophia E. Massinople, Michelle M. Wunder, Zachary L. Ellis, Kaitlyn M. Keith, Tyler Girman, Shelli L. Frey, Justin Legleiter Mar 2024

The Polyglutamine Domain Is The Primary Driver Of Seeding In Huntingtin Aggregation, Adam Skeens, Chathuranga Siriwardhana, Sophia E. Massinople, Michelle M. Wunder, Zachary L. Ellis, Kaitlyn M. Keith, Tyler Girman, Shelli L. Frey, Justin Legleiter

Chemistry Faculty Publications

Huntington’s Disease (HD) is a fatal, neurodegenerative disease caused by aggregation of the huntingtin protein (htt) with an expanded polyglutamine (polyQ) domain into amyloid fibrils. Htt aggregation is modified by flanking sequences surrounding the polyQ domain as well as the binding of htt to lipid membranes. Upon fibrillization, htt fibrils are able to template the aggregation of monomers into fibrils in a phenomenon known as seeding, and this process appears to play a critical role in cell-to-cell spread of HD. Here, exposure of C. elegans expressing a nonpathogenic N-terminal htt fragment (15-repeat glutamine residues) to preformed htt-exon1 fibrils induced …